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1

Nano Sensor Networks for Tailored Operation of Highly Efficient Gas-To-Liquid Fuels Catalysts  

E-Print Network (OSTI)

Nano Sensor Networks for Tailored Operation of Highly Efficient Gas-To-Liquid Fuels Catalysts Eisa Engineering at University of New South Wales. #12;1 Introduction Gas-to-liquid (GTL) compounds are clean fuels for converting natural gas to the liquid hydrocarbons [1]. However, the reaction is a complex network of many

New South Wales, University of

2

Highly ordered Zn-doped mesoporous silica: An efficient catalyst for transesterification reaction  

Science Conference Proceedings (OSTI)

Designing highly ordered material with nanoscale periodicity is of great significance in the field of solid state chemistry. Herein, we report the synthesis of highly ordered 2D-hexagonal mesoporous zinc-doped silica using a mixture of anionic and cationic surfactants under hydrothermal conditions. Powder XRD, N{sub 2} sorption, TEM analysis revealed highly ordered 2D-hexagonal arrangements of the pores with very good surface area (762 m{sup 2} g{sup -1}) in this Zn-rich mesoporous material. Chemical analysis shows very high loading of zinc (ca. 12.0 wt%) in the material together with retention of hexagonal pore structure. Interestingly, high temperature calcination resulted into zinc silicate phase, unlike any ZnO phase, which otherwise is expected under heat treatments. High surface area together with Zn loading in this mesoporous material has been found useful for the catalytic activity of the materials in the acid-catalyzed transesterification reactions of various esters under mild liquid phase conditions. - Graphical abstract: Zn-rich 2D-hexagonal mesoporous materials are synthesized hydrothermally, which show very good catalytic activity in the transesterification reaction under mild liquid phase reaction conditions. Highlights: > Zn-rich 2D-hexagonal mesoporous silica. > High surface area material. > Efficient catalyst in liquid phase transesterification reaction. > Biodiesel production.

Pal, Nabanita; Paul, Manidipa [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India); Bhaumik, Asim, E-mail: msab@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032 (India)

2011-07-15T23:59:59.000Z

3

High Throughput Screening for the Discovery of More Efficient Catalysts for Emissions Control  

DOE Green Energy (OSTI)

High-throughput synthesis and screening methods have been developed for the discovery of highly active catalysts for the control of emissions from stationary and mobile sources. Low temperature CO oxidation, CO methanation, NOx abatement and the destruction of Volatile Organic Compounds (VOCs) will be discussed. The discovery libraries for primary screening consisted of both 11x11 and 16x16 catalyst arrays on 3 inch and 4 inch quartz wafers, respectively. Catalysts were prepared by robotic liquid dispensing techniques and screened for catalytic activity in Symyx's Scanning Mass Spectrometer. The screening protocols encompassed mixed metal oxides, perovskites and supported base and noble metals. Active hits were further optimized in focus libraries using shallower compositional gradients. The ScanMS is a fast serial screening tool that uses flat wafer catalyst surfaces, local laser heating, a scanning/sniffing nozzle and a quadrupolar mass spectrometer to compare relative catalytic activities. The temperature range from 200C to 600C is accessible. Typically, 256 catalysts can be screened per day and about 100,000 experiments conducted annually.

Yaccato, Karin; Hagemeyer, Alfred; Volpe, Anthony; Weinberg, Henry

2004-03-31T23:59:59.000Z

4

The generation of efficient supported (Heterogeneous) olefin metathesis catalysts  

Science Conference Proceedings (OSTI)

Over the past decade, a new family of homogeneous metathesis catalysts has been developed that will tolerate most organic functionalities as well as water and air. These homogeneous catalysts are finding numerous applications in the pharmaceutical industry as well as in the production of functional polymers. In addition the catalysts are being used to convert seed oils into products that can substitute for those that are now made from petroleum products. Seed oils are unsaturated, contain double bonds, and are a ready source of linear hydrocarbon fragments that are specifically functionalized. To increase the number of applications in the area of biomaterial conversion to petrol chemicals, the activity and efficiency of the catalysts need to be as high as possible. The higher the efficiency of the catalysts, the lower the cost of the conversion and a larger number of practical applications become available. Active supported catalysts were prepared and tested in the conversion of seed oils and other important starting materials. The outcome of the work was successful and the technology has been transferred to a commercial operation to develop viable applications of the discovered systems. A biorefinery that converts seed oils is under construction in Indonesia. The catalysts developed in this study will be considered for the next generation of operations.

Grubbs, Robert H

2013-04-05T23:59:59.000Z

5

The three way catalyst efficiency and the gas temperature difference  

Science Conference Proceedings (OSTI)

This work refers to the examination of the three way catalyst efficiency, testing the exhaust gases temperature difference (?T) at the inlet and outlet of the catalyst, using gasoline - ethanol mixtures for fuel, at a catalyst engine functioning ... Keywords: bioethanol, gas emissions, three way catalyst

Charalampos Arapatsakos; Panagiotis Lefakis

2009-02-01T23:59:59.000Z

6

High Temperature Membrane & Advanced Cathode Catalyst Development  

DOE Green Energy (OSTI)

Current project consisted of three main phases and eighteen milestones. Short description of each phase is given below. Table 1 lists program milestones. Phase 1--High Temperature Membrane and Advanced Catalyst Development. New polymers and advanced cathode catalysts were synthesized. The membranes and the catalysts were characterized and compared against specifications that are based on DOE program requirements. The best-in-class membranes and catalysts were downselected for phase 2. Phase 2--Catalyst Coated Membrane (CCM) Fabrication and Testing. Laboratory scale catalyst coated membranes (CCMs) were fabricated and tested using the down-selected membranes and catalysts. The catalysts and high temperature membrane CCMs were tested and optimized. Phase 3--Multi-cell stack fabrication. Full-size CCMs with the down-selected and optimized high temperature membrane and catalyst were fabricated. The catalyst membrane assemblies were tested in full size cells and multi-cell stack.

Protsailo, Lesia

2006-04-20T23:59:59.000Z

7

Nanostructured Cobalt Oxide Clusters in Mesoporous Silica as Efficient Oxygen-Evolving Catalysts  

E-Print Network (OSTI)

as Efficient Oxygen- Evolving Catalysts Feng Jiao and Heinzof efficient and robust catalysts for the chemicaltransformations. Catalysts need to exhibit turnover

Jiao, Feng

2010-01-01T23:59:59.000Z

8

Reducing fischer-tropsch catalyst attrition losses in high ...  

Reducing fischer-tropsch catalyst attrition losses in high agitation reaction systems United States Patent

9

HIGH EFFICIENCY SYNGAS GENERATION  

DOE Green Energy (OSTI)

This project investigated an efficient and low cost method of auto-thermally reforming natural gas to hydrogen and carbon monoxide. Reforming is the highest cost step in producing products such as methanol and Fisher Tropsch liquids (i.e., gas to liquids); and reducing the cost of reforming is the key to reducing the cost of these products. Steam reforming is expensive because of the high cost of the high nickel alloy reforming tubes (i.e., indirectly fired reforming tubes). Conventional auto-thermal or Partial Oxidation (POX) reforming minimizes the size and cost of the reformers and provides a near optimum mixture of CO and hydrogen. However POX requires pure oxygen, which consumes power and significantly increases the cost to reforming. Our high efficiency process extracts oxygen from low-pressure air with novel oxygen sorbent and transfers the oxygen to a nickel-catalyzed reformer. The syngas is generated at process pressure (typically 20 to 40 bar) without nitrogen dilution and has a 1CO to 2H{sub 2} ratio that is near optimum for the subsequent production of Fisher-Tropsch liquid to liquids and other chemicals (i.e., Gas to Liquids, GTL). Our high process efficiency comes from the way we transfer the oxygen into the reformer. All of the components of the process, except for the oxygen sorbent, are commonly used in commercial practice. A process based on a longlived, regenerable, oxygen transfer sorbent could substantially reduce the cost of natural gas reforming to syngas. Lower cost syngas (CO + 2H{sub 2}) that is the feedstock for GTL would reduce the cost of GTL and for other commercial applications (e.g., methanol, other organic chemicals). The vast gas resources of Alaska's North Slope (ANS) offer more than 22 Tcf of gas and GTL production in this application alone, and could account for as much as 300,000 to 700,000 bpd for 20 to 30+ years. We developed a new sorbent, which is an essential part of the High Efficiency Oxygen Process (HOP). We tested the sorbent and observed that it has both a good oxygen capacity and operates as a highly effective reforming catalyst. We conducted a long duration tests of the sorbent (1,500 hours of continuous operation in the HOP cycle). Although the sorbent lost some oxygen capacity with cycling, the sorbent oxygen capacity stabilized after 1,000 hours and remained constant to the end of the test, 1,500 hour. The activity of the catalyst to reform methane to a hydrogen and carbon monoxide mixture was unchanged through the oxidation/reduction cycling. Our cost and performance analyses indicated a significant reduction in the cost of GTL production when using the HOP process integrated into a GTL plant.

Robert J. Copeland; Yevgenia Gershanovich; Brian Windecker

2005-02-01T23:59:59.000Z

10

High-Activity Dealloyed Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

2 fuel cells - Demonstrate durability of the kinetic mass activity against DOE- specified voltage cycling tests in fuel cells - Achieve high current density performance in H 2 air...

11

Highly Dispersed Alloy Catalyst for Durability  

DOE Green Energy (OSTI)

Achieving DOE�¢����s stated 5000-hr durability goal for light-duty vehicles by 2015 will require MEAs with characteristics that are beyond the current state of the art. Significant effort was placed on developing advanced durable cathode catalysts to arrive at the best possible electrode for high performance and durability, as well as developing manufacturing processes that yield significant cost benefit. Accordingly, the overall goal of this project was to develop and construct advanced MEAs that will improve performance and durability while reducing the cost of PEMFC stacks. The project, led by UTC Power, focused on developing new catalysts/supports and integrating them with existing materials (membranes and gas diffusion layers (GDLs)) using state-of-the-art fabrication methods capable of meeting the durability requirements essential for automotive applications. Specifically, the project work aimed to lower platinum group metals (PGM) loading while increasing performance and durability. Appropriate catalysts and MEA configuration were down-selected that protects the membrane, and the layers were tailored to optimize the movements of reactants and product water through the cell to maximize performance while maintaining durability.

Vivek S. Murthi (Primary Contact), Elise Izzo, Wu Bi, Sandra Guerrero and Lesia Protsailo

2013-01-08T23:59:59.000Z

12

A homogenous combustion catalyst for fuel efficiency improvements in diesel engines fuelled with diesel and biodiesel.  

E-Print Network (OSTI)

??[Truncated abstract] The ferrous picrate based homogeneous combustion catalyst has been claimed to promote diesel combustion and improve fuel efficiency in diesel engines. However, the… (more)

Zhu, Mingming

2012-01-01T23:59:59.000Z

13

Identification of Catalysts and Materials for a High-Energy Density Biochemical Fuel Cell: Cooperative Research and Development Final Report, CRADA Number CRD-09-345  

DOE Green Energy (OSTI)

The proposed research attempted to identify novel biochemical catalysts, catalyst support materials, high-efficiency electron transfer agents between catalyst active sites and electrodes, and solid-phase electrolytes in order to maximize the current density of biochemical fuel cells that utilize various alcohols as substrates.

Ghirardi, M.; Svedruzic, D.

2013-07-01T23:59:59.000Z

14

High Efficiency, Clean Combustion  

DOE Green Energy (OSTI)

Energy use in trucks has been increasing at a faster rate than that of automobiles within the U.S. transportation sector. According to the Energy Information Administration (EIA) Annual Energy Outlook (AEO), a 23% increase in fuel consumption for the U.S. heavy duty truck segment is expected between 2009 to 2020. The heavy duty vehicle oil consumption is projected to grow between 2009 and 2050 while light duty vehicle (LDV) fuel consumption will eventually experience a decrease. By 2050, the oil consumption rate by LDVs is anticipated to decrease below 2009 levels due to CAFE standards and biofuel use. In contrast, the heavy duty oil consumption rate is anticipated to double. The increasing trend in oil consumption for heavy trucks is linked to the vitality, security, and growth of the U.S. economy. An essential part of a stable and vibrant U.S. economy is a productive U.S. trucking industry. Studies have shown that the U.S. gross domestic product (GDP) is strongly correlated to freight transport. Over 90% of all U.S. freight tonnage is transported by diesel power and over 75% is transported by trucks. Given the vital role that the trucking industry plays in the economy, improving the efficiency of the transportation of goods was a central focus of the Cummins High Efficient Clean Combustion (HECC) program. In a commercial vehicle, the diesel engine remains the largest source of fuel efficiency loss, but remains the greatest opportunity for fuel efficiency improvements. In addition to reducing oil consumption and the dependency on foreign oil, this project will mitigate the impact on the environment by meeting US EPA 2010 emissions regulations. Innovation is a key element in sustaining a U.S. trucking industry that is competitive in global markets. Unlike passenger vehicles, the trucking industry cannot simply downsize the vehicle and still transport the freight with improved efficiency. The truck manufacturing and supporting industries are faced with numerous challenges to reduce oil consumption and greenhouse gases, meet stringent emissions regulations, provide customer value, and improve safety. The HECC program successfully reduced engine fuel consumption and greenhouse gases while providing greater customer valve. The US EPA 2010 emissions standard poses a significant challenge for developing clean diesel powertrains that meet the DoE Vehicle Technologies Multi-Year Program Plan (MYPP) for fuel efficiency improvement while remaining affordable. Along with exhaust emissions, an emphasis on heavy duty vehicle fuel efficiency is being driven by increased energy costs as well as the potential regulation of greenhouse gases. An important element of the success of meeting emissions while significantly improving efficiency is leveraging Cummins component technologies such as fuel injection equipment, aftertreatment, turbomahcinery, electronic controls, and combustion systems. Innovation in component technology coupled with system integration is enabling Cummins to move forward with the development of high efficiency clean diesel products with a long term goal of reaching a 55% peak brake thermal efficiency for the engine plus aftertreatment system. The first step in developing high efficiency clean products has been supported by the DoE co-sponsored HECC program. The objectives of the HECC program are: (1) To design and develop advanced diesel engine architectures capable of achieving US EPA 2010 emission regulations while improving the brake thermal efficiency by 10% compared to the baseline (a state of the art 2007 production diesel engine). (2) To design and develop components and subsystems (fuel systems, air handling, controls, etc) to enable construction and development of multi-cylinder engines. (3) To perform an assessment of the commercial viability of the newly developed engine technology. (4) To specify fuel properties conducive to improvements in emissions, reliability, and fuel efficiency for engines using high-efficiency clean combustion (HECC) technologies. To demonstrate the technology is compatible with B2

Donald Stanton

2010-03-31T23:59:59.000Z

15

High-Resolution Structure of the Photosynthetic Mn4Ca Catalyst from X-ray Spectroscopy  

E-Print Network (OSTI)

the Photosynthetic Mn 4 Ca Catalyst from X-ray Spectroscopystructure of the Mn 4 Ca catalyst at high-resolution whichthe structure of Mn 4 Ca catalyst as it cycles through the

Yano, Junko

2008-01-01T23:59:59.000Z

16

Break-up of Pt catalyst surfaces by high CO coverage  

E-Print Network (OSTI)

and atomic arrangement of catalyst surface under reactionof reactant molecules on the catalyst surfaces are the norm.Break-up of Pt catalyst surfaces by high CO coverage Feng

Tao, Feng

2010-01-01T23:59:59.000Z

17

CATALYSTS FOR HIGH CETANE ETHERS AS DIESEL FUELS  

DOE Green Energy (OSTI)

A tungstena-zirconia (WZ) catalyst has been investigated for coupling methanol and isobutanol to unsymmetrical ethers, i.e. methyl isobutyl ether (MIBE) and compared with earlier studied sulfated-zirconia (SZ) and Nafion-H catalysts. In all cases, the ether synthesis mechanism is a dual site S{sub N}2 process involving competitive adsorption of reactants on proximal acid sites. At low reaction temperatures, methylisobutylether (MIBE) is the predominant product. However, at temperatures >135 C the WZ catalyst is very good for dehydration of isobutanol to isobutene. The surface acid sites of the WZ catalyst and a Nafion-H catalyst were diagnosed by high resolution X-ray photoelectron spectroscopy (XPS) of N 1s shifts after adsorption of amines. Using pyridine, ethylenediamine, and triethylamine, it is shown that WZ has heterogeneous strong Broensted acid sites. Theoretical study located the transition state of the alcohol coupling reaction on proximal Broensted acid sites and accounted well for XPS core-level shifts upon surface acid-base interactions. While computations have not been carried out with WZ, it is shown that the SZ catalyst is a slightly stronger acid than CF{sub 3}SO{sub 3}H (a model for Nafion-H) by 1.3-1.4 kcal/mol. A novel sulfated zirconia catalyst having proximal strong Broensted acid sites was synthesized and shown to have significantly enhanced activity and high selectivity in producing MIBE or isobutene from methanol/isobutanol mixtures. The catalyst was prepared by anchoring 1,2-ethanediol bis(hydrogen sulfate) salt precursor onto zirconium hydroxide, followed by calcination to remove the -(CH{sub 2}CH{sub 2})- bridging residues.

Kamil Klier; Richard G. Herman; Heock-Hoi Kwon; James G. C. Shen; Qisheng Ma; Robert A. Hunsicker; Andrew P. Butler; Scott J. Bollinger

2003-03-01T23:59:59.000Z

18

High efficiency photoionization detector  

DOE Patents (OSTI)

A high efficiency photoionization detector is described using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 [+-] 0.02 eV, and a vapor pressure of 0.35 torr at 20 C. 6 figs.

Anderson, D.F.

1984-01-31T23:59:59.000Z

19

High efficiency photoionization detector  

DOE Patents (OSTI)

A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36.+-.0.02 eV, and a vapor pressure of 0.35 torr at 20.degree. C.

Anderson, David F. (3055 Trinity, Los Alamos, NM 87544)

1984-01-01T23:59:59.000Z

20

Business Case Slide 22: High-Value: Catalysts - Description  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts - Description Graduate student examining candidate DU-bearing catalyst Graduate student examining candidate DU-bearing catalyst Description Use DUO2 to catalyze chemical...

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Business Case Slide 24: High-Value: Catalysts - Program Focus  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts - Program Focus Program Focus Off-gas cleanup catalysts (ORNL) Best form and substrate, effect of impurities Desulfurization catalyst (Rutgers) Proof-of-principle...

22

High Efficiency Steam Electrolyzer  

SciTech Connect

A novel steam electrolyzer has been developed. In conventional electrolyzers, oxygen produced from electrolysis is usually released in the air stream. In their novel design, natural gas is used to replace air in order to reduce the chemical potential difference across the electrolyzer, thus minimizing the electrical consumption. The oxygen from the electrolysis is consumed in either a total oxidation or a partial oxidation reaction with natural gas. Experiments performed on single cells shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. Using thin film materials and high performance cathode and anode, electrolysis could be done at temperatures as low as 700 C with electrolytic current as high as 1 A/cm{sup 2} at a voltage of 0.5 V only. The 700 C operating temperature is favorable to the total oxidation of natural gas while minimizing the need for steam that is otherwise necessary to avoid carbon deposition. A novel tubular electrolyzer stack has been developed. The system was designed to produce hydrogen at high pressures, taking advantage of the simplicity and high efficiency of the electrochemical compressors. A complete fabrication process was developed for making electrolyzer tubes with thin film coatings. A 100 W stack is being built.

Pham, A.Q.

2000-06-19T23:59:59.000Z

23

Commercialization of a high-performance continuous reforming catalyst  

Science Conference Proceedings (OSTI)

In 1971, the first CCR Platforming process was started up in the US on the Gulf Coast. Twenty-two years later, more than 108 continuous reforming units are operating worldwide. Another 50 CCR Platforming units are in various stages of design, construction, or start-up. Continuous catalytic reforming now represents more than 25% of the world's reforming capacity. Throughout these three decades, the UOP CCR Platforming technology continuously improved in terms of catalyst and process in response to changing industry requirements. Processing conditions in 1993 place tremendous demands on the catalyst in the reforming unit. This paper reviews the challenges and needs of the changing refining industry and the development of a new generation of CCR Platforming catalyst, R-132, and focuses on the first commercial operation of this high-activity, surface-stable catalyst. Case studies show how a refiner can improve margins by using the high activity, yield stability, longer life, and improved chloride retention benefits of this new R-132 Platforming catalyst.

Gilsdorf, N.L.; Doornbos, A.E.; Gevelinger, T.J. (UOP, Des Plaines, IL (United States)); Angelo, C.M.D. (Petrogal Refinaria de Sines (Portugal))

1993-01-01T23:59:59.000Z

24

NREL Team Creates High-Activity, Durable Platinum Extended Surface Catalyst for Fuel Cells (Fact Sheet)  

DOE Green Energy (OSTI)

Researchers with NREL's Fuel Cell team showed that platinum can replace copper nanowires in such a way that high-surface-area and high-specific-activity catalysts are produced, potentially allowing for lower-cost catalysts.

Not Available

2011-02-01T23:59:59.000Z

25

Enhanced High Temperature Performance of NOx Reduction Catalyst Materials  

Science Conference Proceedings (OSTI)

Two primary NOx after-treatment technologies have been recognized as the most promising approaches for meeting stringent NOx emission standards for diesel vehicles within the Environmental Protection Agency’s (EPA’s) 2007/2010 mandated limits, NOx Storage Reduction (NSR) and NH3 selective catalytic reduction (SCR); both are, in fact being commercialized for this application. However, in looking forward to 2015 and beyond with expected more stringent regulations, the continued viability of the NSR technology for controlling NOx emissions from lean-burn engines such as diesels will require at least two specific, significant and inter-related improvements. First, it is important to reduce system costs by, for example, minimizing the precious metal content while maintaining, even improving, performance and long-term stability. A second critical need for future NSR systems, as well as for NH3 SCR, will be significantly improved higher and lower temperature performance and stability. Furthermore, these critically needed improvements will contribute significantly to minimizing the impacts to fuel economy of incorporating these after-treatment technologies on lean-burn vehicles. To meet these objectives will require, at a minimum an improved scientific understanding of the following things: i) the various roles for the precious and coinage metals used in these catalysts; ii) the mechanisms for these various roles; iii) the effects of high temperatures on the active metal performance in their various roles; iv) mechanisms for higher temperature NOx storage performance for modified and/or alternative storage materials; v) the interactions between the precious metals and the storage materials in both optimum NOx storage performance and long term stability; vi) the sulfur adsorption and regeneration mechanisms for NOx reduction materials; vii) materials degradation mechanisms in CHA-based NH3 SCR catalysts. The objective of this CRADA project between PNNL and Cummins, Inc. is to develop a fundamental understanding of the above-listed issues. Model catalysts that are based on literature formulations are the focus of the work being carried out at PNNL. In addition, the performance and stability of more realistic high temperature NSR catalysts, supplied by JM, are being studied in order to provide baseline data for the model catalysts that are, again, based on formulations described in the open literature. For this short summary, we will primarily highlight representative results from our recent studies of the stability of candidate high temperature NSR materials.

Gao, Feng; Kim, Do Heui; Luo, Jinyong; Muntean, George G.; Peden, Charles HF; Howden, Ken; Currier, Neal; Kamasamudram, Krishna; Kumar, Ashok; Li, Junhui; Stafford, Randy; Yezerets, Aleksey; Castagnola, Mario; Chen, Hai Ying; Hess, Howard ..

2012-12-31T23:59:59.000Z

26

Reducing fischer-tropsch catalyst attrition losses in high agitation reaction systems  

DOE Patents (OSTI)

A method for reducing catalyst attrition losses in hydrocarbon synthesis processes conducted in high agitation reaction systems; a method of producing an attrition-resistant catalyst; a catalyst produced by such method; a method of producing an attrition-resistant catalyst support; and a catalyst support produced by such method. The inventive method of reducing catalyst attrition losses comprises the step of reacting a synthesis gas in a high agitation reaction system in the presence of a catalyst. In one aspect, the catalyst preferably comprises a .gamma.-alumina support including an amount of titanium effective for increasing the attrition resistance of the catalyst. In another aspect, the catalyst preferably comprises a .gamma.-alumina support which has been treated, after calcination, with an acidic, aqueous solution. The acidic aqueous solution preferably has a pH of not more than about 5. In another aspect, the catalyst preferably comprises cobalt on a .gamma.-alumina support wherein the cobalt has been applied to the .gamma.-alumina support by totally aqueous, incipient wetness-type impregnation. In another aspect, the catalyst preferably comprises cobalt on a .gamma.-alumina support with an amount of a lanthana promoter effective for increasing the attrition resistance of the catalyst. In another aspect, the catalyst preferably comprises a .gamma.-alumina support produced from boehmite having a crystallite size, in the 021 plane, in the range of from about 30 to about 55 .ANG.ngstrons. In another aspect, the inventive method of producing an attrition-resistant catalyst comprises the step of treating a .gamma.-alumina support, after calcination of and before adding catalytic material to the support, with an acidic solution effective for increasing the attrition resistance of the catalyst. In another aspect, the inventive method of producing an attrition-resistant catalyst support comprises the step of treating calcined .gamma.-alumina with an acidic, aqueous solution effective for increasing the attrition resistance of the .gamma.-alumina.

Singleton, Alan H. (Baden, PA); Oukaci, Rachid (Gibsonia, PA); Goodwin, James G. (Cranberry Township, PA)

2001-01-01T23:59:59.000Z

27

High Efficiency Particulate Air Filters  

NLE Websites -- All DOE Office Websites (Extended Search)

High Efficiency Particulate Air (HEPA) Filters High Efficiency Particulate Air (HEPA) Filters Home Standards DOE Workshops Nuclear Air Cleaning Conference Proceedings Qualified Filter List News Items Related Sites HEPA Related Lessons Learned Contact Us HSS Logo High Efficiency Particulate Air Filters The HEPA Filter web site provides a forum for informing and reporting department-wide activities related to filtration and ventilation issues with special reference to the High Efficiency Particulate Air (HEPA) Filters' use, inspection, and testing. This site contains essentials of DOE HEPA filter test program, procedures, requirements and quality assurance aspects applicable to HEPA filters used in DOE facilities. This site contains information about the DOE-accepted Filter Test Facility and its management, operation and quality assuranceprogram.

28

Highly Dispersed Metal Catalyst - Home - Energy Innovation Portal  

Method for full dispersion of active metals into a high surface area of support to promote efficiency Scientists at the Savannah River National Laboratory have ...

29

High-Efficiency Steam Electrolyzer  

SciTech Connect

We are developing a novel high-efficiency, high-temperature steam electrolyzer. Although water or steam electrolysis is well known to be one of the cleanest ways to produce hydrogen, widespread utilization is hindered by high operational costs because of high electricity consumption. To decrease the electrical power input requirements in electrolysis, our approach uses natural gas as an anode depolarizer. This approach essentially replaces one unit of electricity with one equivalent-energy unit of natural gas at much lower cost. The direct use of natural gas on the electrolyzer enables very high system efficiency with respect to primary energy. Experiments performed on single cells have shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. System efficiency has been estimated to be 50 to 80%, depending on the electrolytic current. A 200-W prototype unit is being developed.

Pham, A Q

2001-06-20T23:59:59.000Z

30

Advanced high efficiency concentrator cells  

DOE Green Energy (OSTI)

This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as follows. (1) A 1.93-eV AlGaAs/1.42-eV GaAs metal-interconnected cascade cell was manufactured with a one-sun efficiency at 27.6% at air mass 1.5 (AM1.5) global. (2) A 1.0eV InGaAs cell was fabricated on the reverse'' side of a low-doped GaAs substrate with a one-sun efficiency of 2.5% AM1.5 diffuse and a short-circuit current of 14.4 mA/cm{sup 2}. (3) Small-scale manufacturing of GaAs p/n concentrator cells was attempted and obtained an excellent yield of high-efficiency cells. (4) Grown-in tunnel junction cell interconnects that are transparent and thermally stable using C and Si dopants were developed. 10 refs.

Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)

1992-06-01T23:59:59.000Z

31

High Efficiency Engine Technologies Program  

Science Conference Proceedings (OSTI)

Caterpillar's Product Development and Global Technology Division carried out a research program on waste heat recovery with support from DOE (Department of Energy) and the DOE National Energy Technology Laboratory. The objective of the program was to develop a new air management and exhaust energy recovery system that would demonstrate a minimum 10% improvement in thermal efficiency over a base heavy-duty on-highway diesel truck engine. The base engine for this program was a 2007 C15 15.2L series-turbocharged on-highway truck engine with a LPL (low-pressure loop) exhaust recirculation system. The focus of the program was on the development of high efficiency turbomachinery and a high efficiency turbocompound waste heat recovery system. The focus of each area of development was as follows: (1) For turbine stages, the focus was on investigation and development of technologies that would improve on-engine exhaust energy utilization compared to the conventional radial turbines in widespread use today. (2) For compressor stages, the focus was on investigating compressor wheel design parameters beyond the range typically utilized in production, to determine the potential efficiency benefits thereof. (3) For turbocompound, the focus was on the development of a robust bearing system that would provide higher bearing efficiencies compared to systems used in turbocompound power turbines in production. None of the turbocharger technologies investigated involved addition of moving parts, actuators, or exotic materials, thereby increasing the likelihood of a favorable cost-value tradeoff for each technology. And the turbocompound system requires less hardware addition than competing bottoming cycle technologies, making it a more attractive solution from a cost and packaging standpoint. Main outcomes of the program are as follows: (1) Two turbine technologies that demonstrated up to 6% improvement in turbine efficiency on gas stand and 1-3% improvement in thermal efficiency in on-engine testing. (2) A compressor technology that demonstrated 1.5% improvement in compressor efficiency on gas stand compared to production available compressors. (3) A power turbine with high efficiency bearing system that demonstrated excellent rotordynamic stability throughout the required speed range, up to 60,000 rpm. (4) A predicted improvement (using engine simulation) in engine thermal efficiency of 7% at the peak torque design point, when combining the technologies developed in this program.

Rich Kruiswyk

2010-07-13T23:59:59.000Z

32

Enabling High Efficiency Ethanol Engines  

Science Conference Proceedings (OSTI)

Delphi Automotive Systems and ORNL established this CRADA to explore the potential to improve the energy efficiency of spark-ignited engines operating on ethanol-gasoline blends. By taking advantage of the fuel properties of ethanol, such as high compression ratio and high latent heat of vaporization, it is possible to increase efficiency with ethanol blends. Increasing the efficiency with ethanol-containing blends aims to remove a market barrier of reduced fuel economy with E85 fuel blends, which is currently about 30% lower than with petroleum-derived gasoline. The same or higher engine efficiency is achieved with E85, and the reduction in fuel economy is due to the lower energy density of E85. By making ethanol-blends more efficient, the fuel economy gap between gasoline and E85 can be reduced. In the partnership between Delphi and ORNL, each organization brought a unique and complementary set of skills to the project. Delphi has extensive knowledge and experience in powertrain components and subsystems as well as overcoming real-world implementation barriers. ORNL has extensive knowledge and expertise in non-traditional fuels and improving engine system efficiency for the next generation of internal combustion engines. Partnering to combine these knowledge bases was essential towards making progress to reducing the fuel economy gap between gasoline and E85. ORNL and Delphi maintained strong collaboration throughout the project. Meetings were held regularly, usually on a bi-weekly basis, with additional reports, presentations, and meetings as necessary to maintain progress. Delphi provided substantial hardware support to the project by providing components for the single-cylinder engine experiments, engineering support for hardware modifications, guidance for operational strategies on engine research, and hardware support by providing a flexible multi-cylinder engine to be used for optimizing engine efficiency with ethanol-containing fuels.

Szybist, J.; Confer, K. (Delphi Automotive Systems)

2011-03-01T23:59:59.000Z

33

Evaluating High Efficiency Motor Retrofit  

E-Print Network (OSTI)

In the petrochemical and refining Industries, and most manufacturing plants, the reliable operation of AC motors always has been crucial to the continuous operation of the process. Now, the cost of operating these motors has also become a significant factor. Engineers Involved In motor specification can help lower plant operating costs and reduce electrical energy consumption dramatically by a relatively simple technique: retrofit of existing, standard-efficiency motors with new, high efficiency models. This article demonstrates strong reasons for motor retrofit, and explains step-by step how process and manufacturing engineering personnel can fully evaluate a retrofit decision.

Evans, T. A.

1984-01-01T23:59:59.000Z

34

High-Efficiency Steam Electrolyzer  

SciTech Connect

We are developing a novel high-efficiency, high-temperature steam electrolyzer. Although water or steam electrolysis is well known to be one of the cleanest ways to produce hydrogen, widespread utilization is hindered by high operational costs because of high electricity consumption. To decrease the electrical power input requirements in electrolysis, our approach uses natural gas as an anode depolarizer. This approach essentially replaces one unit of electricity with one equivalent-energy unit of natural gas at much lower cost. The direct use of natural gas on the electrolyzer enables very high system efficiency with respect to primary energy. Experiments performed on single cells have shown a voltage reduction as much as 1 V when compared to conventional electrolyzers. System efficiency has been estimated to be 50 to 80%, depending on the electrolytic current density. During FY02, we have accomplished several major milestones, including the development of a metal-to-ceramic seal that withstands 150 psi differential, the fabrication of the electrolyzer tubes of up to 16 inches in length, the improvement of single tube performance and the demonstration of the first electrolyzer stack.

Pham, A Q; See, E; Lenz, D; Martin, P; Glass, R

2002-07-03T23:59:59.000Z

35

Subnanometer platinum clusters highly active and selective catalysts for the oxidative dehydrogenation of propane.  

Science Conference Proceedings (OSTI)

Small clusters are known to possess reactivity not observed in their bulk analogues, which can make them attractive for catalysis. Their distinct catalytic properties are often hypothesized to result from the large fraction of under-coordinated surface atoms. Here, we show that size-preselected Pt{sub 8-10} clusters stabilized on high-surface-area supports are 40-100 times more active for the oxidative dehydrogenation of propane than previously studied platinum and vanadia catalysts, while at the same time maintaining high selectivity towards formation of propylene over by-products. Quantum chemical calculations indicate that under-coordination of the Pt atoms in the clusters is responsible for the surprisingly high reactivity compared with extended surfaces. We anticipate that these results will form the basis for development of a new class of catalysts by providing a route to bond-specific chemistry, ranging from energy-efficient and environmentally friendly synthesis strategies to the replacement of petrochemical feedstocks by abundant small alkanes.

Vajda, S; Pellin, M. J.; Greeley, J. P.; Marshall, C. L.; Curtiss, L. A.; Ballentine, G. A.; Elam, J. W.; Catillon-Mucherie, S.; Redfern, P. C.; Mehmood, F.; Zapol, P.; Yale Univ.

2009-03-01T23:59:59.000Z

36

High-efficiency photoionization detector  

DOE Patents (OSTI)

A high efficiency photoionization detector using tetraaminoethylenes in a gaseous state having a low ionization potential and a relative photoionization cross section which closely matches the emission spectrum of xenon gas. Imaging proportional counters are also disclosed using the novel photoionization detector of the invention. The compound of greatest interest is TMAE which comprises tetrakis(dimethylamino)ethylene which has a measured ionization potential of 5.36 +- 0.02 eV, and a vapor pressure of 0.35 torr at 20/sup 0/C.

Anderson, D.F.

1981-05-12T23:59:59.000Z

37

Possible Origin of Improved High Temperature Performance of Hydrothermally Aged Cu/Beta Zeolite Catalysts  

SciTech Connect

The hydrothermal stability of Cu/beta NH3 SCR catalysts are explored here. In particular, this paper focuses on the interesting ability of this catalyst to maintain and even enhance high-temperature performance for the "standard" SCR reaction after modest (900 °C, 2 hours) hydrothermal aging. Characterization of the fresh and aged catalysts was performed with an aim to identify possible catalytic phases responsible for the enhanced high temperature performance. XRD, TEM and 27Al NMR all showed that the hydrothermally aging conditions used here resulted in almost complete loss of the beta zeolite structure between 1 and 2 hours aging. While the 27Al NMR spectra of 2 and 10 hour hydrothermally-aged catalysts showed significant loss of a peak associated with tetrahedrally-coordinated Al species, no new spectral features were evident. Two model catalysts, suggested by these characterization data as possible mimics of the catalytic phase formed during hydrothermal aging of Cu/beta, were prepared and tested for their performance in the "standard" SCR and NH3 oxidation reactions. The similarity in their reactivity compared to the 2 hour hydrothermally-aged Cu/beta catalyst suggests possible routes for preparing multi-component catalysts that may have wider temperature windows for optimum performance than those provided by current Cu/zeolite catalysts.

Peden, Charles HF; Kwak, Ja Hun; Burton, Sarah D.; Tonkyn, Russell G.; Kim, Do Heui; Lee, Jong H.; Jen, H. W.; Cavattaio, Giovanni; Cheng, Yisun; Lambert, Christine

2012-04-30T23:59:59.000Z

38

High Efficiency Fans and High Efficiency Electrical Motors  

E-Print Network (OSTI)

Replacing nominal efficient electrical motors with premium efficiency can save on electrical power costs in cotton gins. Connected horsepower load on industrial air fans is approximately 60% of the total horsepower in a typical cotton gin. By replacing old inefficient centrifugal fans with new higher efficiency fans, additional power savings can be achieved.

Breedlove, C. W.

1989-09-01T23:59:59.000Z

39

High-efficiency photovoltaic cells  

DOE Patents (OSTI)

High efficiency solar converters comprised of a two cell, non-lattice matched, monolithic stacked semiconductor configuration using optimum pairs of cells having bandgaps in the range 1.6 to 1.7 eV and 0.95 to 1.1 eV, and a method of fabrication thereof, are disclosed. The high band gap subcells are fabricated using metal organic chemical vapor deposition (MOCVD), liquid phase epitaxy (LPE) or molecular beam epitaxy (MBE) to produce the required AlGaAs layers of optimized composition, thickness and doping to produce high performance, heteroface homojunction devices. The low bandgap subcells are similarly fabricated from AlGa(As)Sb compositions by LPE, MBE or MOCVD. These subcells are then coupled to form a monolithic structure by an appropriate bonding technique which also forms the required transparent intercell ohmic contact (IOC) between the two subcells. Improved ohmic contacts to the high bandgap semiconductor structure can be formed by vacuum evaporating to suitable metal or semiconductor materials which react during laser annealing to form a low bandgap semiconductor which provides a low contact resistance structure.

Yang, H.T.; Zehr, S.W.

1982-06-21T23:59:59.000Z

40

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime, high frequency, high power bursts of low-duty factor microwaves sufficient to generate a plasma discharge and passing a gas to be treated through the discharge so as to cause dissociative reduction of the exhaust gases and enhanced catalyst reactivity through application of the pulsed microwave fields directly to the catalyst material sufficient to cause a polarizability catastrophe and enhanced heating of the metal crystallite particles of the catalyst, and in the presence or absence of the plasma. The invention also includes a reactor for aftertreatment of exhaust gases.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Ypsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2002-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

High Aspect Ratio Nano-Structured Pt-based PEM Fuel Cell Catalysts...  

NLE Websites -- All DOE Office Websites (Extended Search)

or * nanoplates - Ni, Co, and Fe have been selected as V.D.14 High Aspect Ratio Nano-Structured Pt-Based PEM Fuel Cell Catalysts Table 1. Technical Targets for...

42

High efficiency shale oil recovery  

SciTech Connect

The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical conditions (heating, mixing, pyrolysis, oxidation) exist in both systems.The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed this quarter. (1) Twelve pyrolysis runs were made on five different oil shales. All of the runs exhibited a complete absence of any plugging, tendency. Heat transfer for Green River oil shale in the rotary kiln was 84.6 Btu/hr/ft[sup 2]/[degrees]F, and this will provide for ample heat exchange in the Adams kiln. (2) One retorted residue sample was oxidized at 1000[degrees]F. Preliminary indications are that the ash of this run appears to have been completely oxidized. (3) Further minor equipment repairs and improvements were required during the course of the several runs.

Adams, D.C.

1993-04-22T23:59:59.000Z

43

High efficiency shale oil recovery  

SciTech Connect

The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated at bench-scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although a batch oil shale sample will be sealed in the batch kiln from the start until the end of the run, the process conditions for the batch will be the same as the conditions that an element of oil shale would encounter in a large continuous process kiln. For example, similar conditions of heat-up rate (20 deg F/min during the pyrolysis), oxidation of the residue and cool-down will prevail for the element in both systems. This batch kiln is a unit constructed in a 1987 Phase I SBIR tar sand retorting project. The kiln worked fairly well in that project; however, the need for certain modifications was observed. These modifications are now underway to simplify the operation and make the data and analysis more exact. The agenda for the first three months of the project consisted of the first of nine tasks and was specified as the following four items: 1. Sample acquisition and equipment alteration: Obtain seven oil shale samples, of varying grade each 10 lb or more, and samples of quartz sand. Order equipment for kiln modification. 3. Set up and modify kiln for operation, including electric heaters on the ends of the kiln. 4. Connect data logger and make other repairs and changes in rotary batch kiln.

Adams, D.C.

1992-01-01T23:59:59.000Z

44

High efficiency shale oil recovery  

SciTech Connect

The overall project objective is to demonstrate the high efficiency of the Adams Counter-Current shale oil recovery process. The efficiency will first be demonstrated on a small scale, in the current phase, after which the demonstration will be extended to the operation of a small pilot plant. Thus the immediate project objective is to obtain data on oil shale retorting operations in a small batch rotary kiln that will be representative of operations in the proposed continuous process pilot plant. Although an oil shale batch sample is sealed in the batch kiln from the start until the end of the run, the process conditions for the batch are the same as the conditions that an element of oil shale would encounter in a continuous process kiln. Similar chemical and physical (heating, mixing) conditions exist in both systems. The two most important data objectives in this phase of the project are to demonstrate (1) that the heat recovery projected for this project is reasonable and (2) that an oil shale kiln will run well and not plug up due to sticking and agglomeration. The following was completed and is reported on this quarter: (1) A software routine was written to eliminate intermittently inaccurate temperature readings. (2) We completed the quartz sand calibration runs, resolving calibration questions from the 3rd quarter. (3) We also made low temperature retorting runs to identify the need for certain kiln modifications and kiln modifications were completed. (4) Heat Conductance data on two Pyrolysis runs were completed on two samples of Occidental oil shale.

Adams, D.C.

1992-01-01T23:59:59.000Z

45

Effects of Chlorine and Other Flue Gas Parameters on SCR Catalyst Mercury Oxidation and Capture Efficiencies  

Science Conference Proceedings (OSTI)

Although catalyst behavior is relatively well understood with respect to deNOx and SO2 oxidation, relatively little is known about mercury oxidation behavior. This test program seeks to evaluate the mercury oxidation performance of multiple types of Selective Catalytic Reduction (SCR) catalyst as a function of changes in various flue gas parameters, including chlorine level, ammonia level, flow rate, and temperature. This interim report describes the results from parametric testing on the first catalyst.

2008-08-27T23:59:59.000Z

46

Bringing Energy Efficiency to High Performance Computing  

NLE Websites -- All DOE Office Websites (Extended Search)

Bringing Energy Efficiency to High Performance Computing Oak Ridge National Laboratory's Jaguar Supercomputer William Tschudi September 2013 The ability of high performance...

47

Design of a high activity and selectivity alcohol catalyst  

DOE Green Energy (OSTI)

In order to explore the secondary dehydration of methanol over [gamma]-Al[sub 2]O[sub 3] support and over bimetallic Rh-Mo/[gamma]- Al[sub 2]O[sub 3], a new series of K-doped Rh-Mo/[gamma]-Al[sub 2]O[sub 3] catalysts was synthesized. Work on synthesis of bimetallic Rh-Mo clusters is reported.

Foley, H.C.; Mills, G.A.

1992-06-04T23:59:59.000Z

48

High-Efficiency Neutron Detection and Spectroscopy  

Science Conference Proceedings (OSTI)

High-Efficiency Neutron Detection and Spectroscopy. ... such as searches for WIMP dark matter, neutrinoless double beta decay, and solar neutrinos. ...

2013-07-22T23:59:59.000Z

49

High-Efficiency Neutron Detection and Spectroscopy ...  

Science Conference Proceedings (OSTI)

... are also working on a large volume detector to use in the underground environment where high efficiency is more important that energy resolution. ...

2013-07-22T23:59:59.000Z

50

Efficient high density train operations  

DOE Patents (OSTI)

The present invention provides methods for preventing low train voltages and managing interference, thereby improving the efficiency, reliability, and passenger comfort associated with commuter trains. An algorithm implementing neural network technology is used to predict low voltages before they occur. Once voltages are predicted, then multiple trains can be controlled to prevent low voltage events. Further, algorithms for managing inference are presented in the present invention. Different types of interference problems are addressed in the present invention such as "Interference. During Acceleration", "Interference Near Station Stops", and "Interference During Delay Recovery." Managing such interference avoids unnecessary brake/acceleration cycles during acceleration, immediately before station stops, and after substantial delays. Algorithms are demonstrated to avoid oscillatory brake/acceleration cycles due to interference and to smooth the trajectories of closely following trains. This is achieved by maintaining sufficient following distances to avoid unnecessary braking/accelerating. These methods generate smooth train trajectories, making for a more comfortable ride, and improve train motor reliability by avoiding unnecessary mode-changes between propulsion and braking. These algorithms can also have a favorable impact on traction power system requirements and energy consumption.

Gordon, Susanna P. (Oakland, CA); Evans, John A. (Hayward, CA)

2001-01-01T23:59:59.000Z

51

High Efficiency New Metallurgical Technology  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... The alumina leaching rate of calcium aluminate in residue is over 80%. .... Different types of plasma torches including a high power steam plasma torch ... for about 50% of the total NOX emissions in the iron and steel industry.

52

Multicolor, High Efficiency, Nanotextured LEDs  

SciTech Connect

We report on research results in this project which synergize advanced material science approaches with fundamental optical physics concepts pertaining to light-matter interaction, with the goal of solving seminal problems for the development of very high performance light emitting diodes (LEDs) in the blue and green for Solid State Lighting applications. Accomplishments in the duration of the contract period include (i) heteroepitaxy of nitrogen-polar LEDs on sapphire, (ii) heteroepitaxy of semipolar (11{bar 2}2) green LEDs on sapphire, (iii) synthesis of quantum-dot loaded nanoporous GaN that emits white light without phosphor conversion, (iv) demonstration of the highest quality semipolar (11{bar 2}2) GaN on sapphire using orientation-controlled epitaxy, (v) synthesis of nanoscale GaN and InGaN medium, and (vi) development of a novel liftoff process for manufacturing GaN thin-film vertical LEDs. The body of results is presented in this report shows how a solid foundation has been laid, with several noticeable accomplishments, for innovative research, consistent with the stated milestones.

Jung Han; Arto Nurmikko

2011-09-30T23:59:59.000Z

53

Sequential high temperature reduction, low temperature hydrolysis for the regeneration of sulfated NOx trap catalysts  

SciTech Connect

We describe a new method that minimizes irreversible Pt sintering during the desulfation of sulfated Pt/BaO/Al2O3 lean NOx trap (LNT) catalysts. While it is known that the addition of H2O to H2 promotes desulfation, we find that the significant and irreversible Pt sintering arising from the presence of water is unavoidable. Control of precious metal sintering is considered to be one of the critical issues in the development of durable LNT catalysts. The new method described here is a sequential desulfation process: the first step is to reduce the sulfates with hydrogen only at higher temperatures to form BaS, followed by a treatment of the thus reduced sample with water at low to moderate temperatures to convert BaS to BaO and H2S. The data showed that Pt sintering was significantly inhibited due to the absence of H2O during the desulfation at high temperatures, and also demonstrates the similar NOx uptake with the desulfated sample cooperatively with H2 and H2O. Therefore, the sequential desulfation process may find applications in realistic systems to inhibit the irreversible sintering of the Pt in the lean NOx trap catalyst, leading to a longer catalyst life.

Kim, Do Heui; Kwak, Ja Hun; Wang, Xianqin; Szanyi, Janos; Peden, Charles HF

2008-07-15T23:59:59.000Z

54

DYNAMOMETER EVALUATION OF PLASMA-CATALYST FOR DIESEL NOX REDUCTION  

DOE Green Energy (OSTI)

A three-stage plasma-catalyst system was developed and tested on an engine dynamometer. Previous laboratory testing suggested high NOx efficiency could be obtained. With hexene reductant added to the exhaust, over 90% NOx reduction was observed. However, with diesel or Fischer-Tropsch reductant the catalyst efficiency rapidly dropped off. Heating the catalyst in air removed brown deposit from the surface and restored conversion efficiency. Following the engine tests, the used catalysts were evaluated. BET surface area decreased, and TPD revealed significant storage. This storage appears to be partly unburned diesel fuel that can be removed by heating to around 250-300 C, and partly hydrocarbons bonded to the surface that remain in place until 450-500 C. Laboratory testing with propene reductant demonstrated that the catalyst regains efficiency slowly even when operating temperature does not exceed 300 C. This suggests that control strategies may be able to regenerate the catalyst by occasional moderate heating.

Hoard, J; Schmieg, S; Brooks, D; Peden, C; Barlow, S; Tonkyn, R

2003-08-24T23:59:59.000Z

55

Better Enzymes for Carbon Capture: Low-Cost Biological Catalyst to Enable Efficient Carbon Dioxide Capture  

Science Conference Proceedings (OSTI)

IMPACCT Project: Codexis is developing new and efficient forms of enzymes known as carbonic anhydrases to absorb CO2 more rapidly and under challenging conditions found in the gas exhaust of coal-fired power plants. Carbonic anhydrases are common and are among the fastest enzymes, but they are not robust enough to withstand the harsh environment found in the power plant exhaust steams. In this project, Codexis will be using proprietary technology to improve the enzymes’ ability to withstand high temperatures and large swings in chemical composition. The project aims to develop a carbon-capture process that uses less energy and less equipment than existing approaches. This would reduce the cost of retrofitting today’s coal-fired power plants.

None

2010-07-01T23:59:59.000Z

56

Measure Guideline: High Efficiency Natural Gas Furnaces  

SciTech Connect

This Measure Guideline covers installation of high-efficiency gas furnaces. Topics covered include when to install a high-efficiency gas furnace as a retrofit measure, how to identify and address risks, and the steps to be used in the selection and installation process. The guideline is written for Building America practitioners and HVAC contractors and installers. It includes a compilation of information provided by manufacturers, researchers, and the Department of Energy as well as recent research results from the Partnership for Advanced Residential Retrofit (PARR) Building America team.

Brand, L.; Rose, W.

2012-10-01T23:59:59.000Z

57

Deposition and Characterization of Highly Oriented Mg(3)(VO(4))(2) Thin Film Catalyst  

DOE Green Energy (OSTI)

Magnesium vanadates are potentially important catalytic materials for the conversion of alkanes to alkenes via oxidative dehydrogenation. However, little is known about the active sites at which the catalytic reactions take place. It may be possible to obtain a significant increase in the catalytic efficiency if the effects of certain material properties on the surface reactions could be quantified and optimized through the use of appropriate preparation techniques. Given that surface reactivity is often dependent upon surface structure and that the atomic level structure of the active sites in these catalysts is virtually unknown, we desire thin film samples consisting of a single magnesium vanadate phase and a well defined crystallographic orientation in order to reduce complexity and simplify the study of active sites. We report on the use of reactive RF sputter deposition to fabricate very highly oriented, stoichiometric Mg{sub 3}(VO{sub 4}){sub 2} thin films for use in these surface analysis studies. Deposition of samples onto amorphous substrates resulted in very poor crystallinity. However, deposition of Mg{sub 3}(VO{sub 4}){sub 2} onto well-oriented, lattice-matched thin film ''seed'' layers such as Ti(0001), Au(111), or Pt(111) resulted in very strong preferential (042) crystallographic orientation (pseudo-hexagonal oxygen planes parallel to the substrate). This strong preferential growth of the Mg{sub 3}VO{sub 4}{sub 2} suggests epitaxial (single-crystal) growth of this mixed metal oxide on the underlying metal seed layer. The effects of the seed layer material, deposition temperature, and post-deposition reactive treatments on thin film properties such as stoichiometry, crystallographic orientation, and chemical interactions will be discussed.

RODRIGUEZ,MARK A.; RUFFNER,JUDITH A.; SAULT,ALLEN G.; TISSOT JR.,RALPH G.

1999-10-22T23:59:59.000Z

58

Implications of Low Particulate Matter Emissions on System Fuel Efficiency for High Efficiency Clean Combustion  

DOE Green Energy (OSTI)

Advanced diesel combustion regimes such as High Efficiency Clean Combustion (HECC) offer the benefits of reduced engine out NOX and particulate matter (PM) emissions. Lower PM emissions during advanced combustion reduce the demand on diesel particulate filters (DPFs) and can, thereby, reduce the fuel penalty associated with DPF regeneration. In this study, a SiC DPF was loaded and regenerated on a 1.7-liter 4-cylinder diesel engine operated in conventional and advanced combustion modes at different speed and load conditions. A diesel oxidation catalyst (DOC) and a lean NOX trap (LNT) were also installed in the exhaust stream. Five steady-state speed and load conditions were weighted to estimate Federal Test Procedure (FTP) fuel efficiency. The DPF was loaded using lean-rich cycling with frequencies that resulted in similar levels of NOX emissions downstream of the LNT. The pressure drop across the DPF was measured at a standard point (1500 rpm, 5.0 bar) before and after loading, and a P rise rate was determined for comparison between conventional and advanced combustion modes. Higher PM emissions in conventional combustion resulted in a higher rate of backpressure rise across the DPF at all of the load points leading to more frequent DPF regenerations and higher fuel penalty. The fuel penalty during conventional combustion was 4.2% compared with 3.1% for a mixture of conventional and advanced modes.

Parks, II, James E [ORNL; Prikhodko, Vitaly Y [ORNL

2009-01-01T23:59:59.000Z

59

A carbon riveted Pt/Graphene catalyst with high stability for direct methanol fuel cell  

Science Conference Proceedings (OSTI)

Pt/Graphene catalyst was prepared by microwave-assisted polyol process, and carbonization was riveted onto the catalyst surface to enhance the catalyst stability. The physical properties of the obtained catalysts were characterized by X-ray diffraction ... Keywords: Direct methanol fuel cell, Methanol electrooxidation, Pt/Graphene, Stability

Xiaowei Liu, Jialin Duan, Hailong Chen, Yufeng Zhang, Xuelin Zhang

2013-10-01T23:59:59.000Z

60

High Efficiency Solar Integrated Roof Membrane Product  

SciTech Connect

This project was designed to address the Solar Energy Technology Program objective, to develop new methods to integrate photovoltaic (PV) cells or modules within a building-integrated photovoltaic (BIPV) application that will result in lower installed cost as well as higher efficiencies of the encapsulated/embedded PV module. The technology assessment and development focused on the evaluation and identification of manufacturing technologies and equipment capable of producing such low-cost, high-efficiency, flexible BIPV solar cells on single-ply roofing membranes.

Partyka, Eric; Shenoy, Anil

2013-05-15T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

High-efficiency silicon concentrator cell commercialization  

SciTech Connect

This report summarizes the first phase of a forty-one month program to develop a commercial, high-efficiency concentrator solar cell and facility for manufacturing it. The period covered is November 1, 1990 to December 31, 1991. This is a joint program between the Electric Power Research Institute (EPRI) and Sandia National Laboratories. (This report is also published by EPRI as EPRI report number TR-102035.) During the first year of the program, SunPower accomplished the following major objectives: (1) a new solar cell fabrication facility, which is called the Cell Pilot Line (CPL), (2) a baseline concentrator cell process has been developed, and (3) a cell testing facility has been completed. Initial cell efficiencies are about 23% for the baseline process. The long-range goal is to improve this efficiency to 27%.

Sinton, R.A.; Swanson, R.M. [SunPower Corp., Sunnyvale, CA (US)

1993-05-01T23:59:59.000Z

62

Building Technologies Office: Highly Energy Efficient Wall Systems...  

NLE Websites -- All DOE Office Websites (Extended Search)

Highly Energy Efficient Wall Systems Research Project to someone by E-mail Share Building Technologies Office: Highly Energy Efficient Wall Systems Research Project on Facebook...

63

Energy Efficiency Opportunities in Federal High Performance Computing...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Energy Efficiency Opportunities in Federal High Performance Computing Data Centers Energy Efficiency Opportunities in Federal High Performance Computing Data Centers Case study...

64

Vehicle Technologies Office: Materials for High Efficiency Combustion...  

NLE Websites -- All DOE Office Websites (Extended Search)

High Efficiency Combustion Engines to someone by E-mail Share Vehicle Technologies Office: Materials for High Efficiency Combustion Engines on Facebook Tweet about Vehicle...

65

High efficiency inverter and ballast circuits  

SciTech Connect

A high efficiency push-pull inverter circuit employing a pair of relatively high power switching transistors is described. The switching on and off of the transistors is precisely controlled to minimize power losses due to common-mode conduction or due to transient conditions that occur in the process of turning a transistor on or off. Two current feed-back transformers are employed in the transistor base drives; one being saturable for providing a positive feedback, and the other being non-saturable for providing a subtractive feedback.

Nilssen, O.K.

1984-02-07T23:59:59.000Z

66

Multi-band high efficiency power amplifier  

E-Print Network (OSTI)

Baseline) Output Power (Transformer) Drain Efficiency (Performance Frequency (GHz) Output Power (Transformer) DrainEfficiency (Transformer) Output Power (Baseline) Drain

Besprozvanny, Randy-Alexander Randolph

2011-01-01T23:59:59.000Z

67

Building Technologies Office: High Efficiency, Low Emission Supermarket  

NLE Websites -- All DOE Office Websites (Extended Search)

High Efficiency, Low High Efficiency, Low Emission Supermarket Refrigeration Research Project to someone by E-mail Share Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Facebook Tweet about Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Twitter Bookmark Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Google Bookmark Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Delicious Rank Building Technologies Office: High Efficiency, Low Emission Supermarket Refrigeration Research Project on Digg Find More places to share Building Technologies Office: High

68

Highly Efficient Silicon Light Emitting Diode  

E-Print Network (OSTI)

In this paper, we describe the fabrication, using standard silicon processing techniques, of silicon light-emitting diodes (LED) that efficiently emit photons with energy around the silicon bandgap. The improved efficiency had been explained by the spatial confinement of charge carriers due to a local strain field that is formed by dislocation loop arrays. The dependence of device electroluminescent properties on the annealing conditions is carefully examined as a high temperature process has profound influence on these dislocations. Increased luminescent intensity at higher device temperature, together with pure diffusion current conduction mechanism evidently shows the influence of the dislocation loops. The electrical properties of the diode are reasonable with low leakage reverse current.

Leminh Holleman Wallinga; P. Leminh; J. Holleman; H. Wallinga

2000-01-01T23:59:59.000Z

69

Status of the Development and Assessment of Advanced NOx Catalysts  

Science Conference Proceedings (OSTI)

This is an interim report summarizing the status of EPRI's advanced nitrogen oxides (NOx) reduction catalyst development efforts in 2000. Concepts for that are more effective, lower cost, and may not have the problems associated with the standard vanadium pentoxide - titanium dioxide (V2O5-TiO2) NOx selective catalytic reduction (SCR) catalysts that have been assessed under this program. The primary efforts in 2000 included further development of an ultra-high efficiency (UHE) catalyst, determining wheth...

2000-11-27T23:59:59.000Z

70

Business Case Slide 23: High-Value: Catalysts - Basis for Use  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalysts - Basis for Use Basis for use DUO2 has previously been used as a catalyst Dissociation of volatile organic compounds and nitrogen oxides in off-gas streams Oxidation of...

71

Energy Efficiency Opportunities in Federal High Performance Computing Data Centers  

Energy.gov (U.S. Department of Energy (DOE))

Case study describes an outline of energy efficiency opportunities in federal high performance computing data centers.

72

High efficiency compressor uses direct drive  

Science Conference Proceedings (OSTI)

This article focuses on the high efficiency of a compressor which uses only direct drive. This compressor was evaluated by judges and won Top Honors in the 1982 Chemical Processing magazine Vaaler Awards category of compressors, blowers and fans. Applications for the compressor include combustion air, process air and gas booster, incineration, fermentation, and vacuum filtration systems. In addition to a 50% reduction in power comsumption, the use of the compressor eliminated the need for a water seal, thus saving 200 gpm of water. And, since the elimination of the water seal reduced the necessary downtime for seal maintenance, on stream time was increased by 5%.

Not Available

1982-11-01T23:59:59.000Z

73

High-efficiency concentrator silicon solar cells  

DOE Green Energy (OSTI)

This report presents results from extensive process development in high-efficiency Si solar cells. An advanced design for a 1.56-cm{sup 2} cell with front grids achieved 26% efficiency at 90 suns. This is especially significant since this cell does not require a prismatic cover glass. New designs for simplified backside-contact solar cells were advanced from a status of near-nonfunctionality to demonstrated 21--22% for one-sun cells in sizes up to 37.5 cm{sup 2}. An efficiency of 26% was achieved for similar 0.64-cm{sup 2} concentrator cells at 150 suns. More fundamental work on dopant-diffused regions is also presented here. The recombination vs. various process and physical parameters was studied in detail for boron and phosphorous diffusions. Emitter-design studies based solidly upon these new data indicate the performance vs design parameters for a variety of the cases of most interest to solar cell designers. Extractions of p-type bandgap narrowing and the surface recombination for p- and n-type regions from these studies have a generality that extends beyond solar cells into basic device modeling. 68 refs., 50 figs.

Sinton, R.A.; Cuevas, A.; King, R.R.; Swanson, R.M. (Stanford Univ., CA (USA). Solid-State Electronics Lab.)

1990-11-01T23:59:59.000Z

74

High Efficiency, Illumination Quality OLEDs for Lighting  

SciTech Connect

The goal of the program was to demonstrate a 45 lumen per watt white light device based upon the use of multiple emission colors through the use of solution processing. This performance level is a dramatic extension of the team's previous 15 LPW large area illumination device. The fundamental material system was based upon commercial polymer materials. The team was largely able to achieve these goals, and was able to deliver to DOE a 90 lumen illumination source that had an average performance of 34 LPW a 1000 cd/m{sup 2} with peak performances near 40LPW. The average color temperature is 3200K and the calculated CRI 85. The device operated at a brightness of approximately 1000cd/m{sup 2}. The use of multiple emission colors particularly red and blue, provided additional degrees of design flexibility in achieving white light, but also required the use of a multilayered structure to separate the different recombination zones and prevent interconversion of blue emission to red emission. The use of commercial materials had the advantage that improvements by the chemical manufacturers in charge transport efficiency, operating life and material purity could be rapidly incorporated without the expenditure of additional effort. The program was designed to take maximum advantage of the known characteristics of these material and proceeded in seven steps. (1) Identify the most promising materials, (2) assemble them into multi-layer structures to control excitation and transport within the OLED, (3) identify materials development needs that would optimize performance within multilayer structures, (4) build a prototype that demonstrates the potential entitlement of the novel multilayer OLED architecture (5) integrate all of the developments to find the single best materials set to implement the novel multilayer architecture, (6) further optimize the best materials set, (7) make a large area high illumination quality white OLED. A photo of the final deliverable is shown. In 2003, a large area, OLED based illumination source was demonstrated that could provide light with a quality, quantity, and efficiency on par with what can be achieved with traditional light sources. The demonstration source was made by tiling together 16 separate 6-inch x 6-inch blue-emitting OLEDs. The efficiency, total lumen output, and lifetime of the OLED based illumination source were the same as what would be achieved with an 80 watt incandescent bulb. The devices had an average efficacy of 15 LPW and used solution-processed OLEDs. The individual 6-inch x 6-inch devices incorporated three technology strategies developed specifically for OLED lighting -- downconversion for white light generation, scattering for outcoupling efficiency enhancement, and a scalable monolithic series architecture to enable large area devices. The downconversion approach consists of optically coupling a blue-emitting OLED to a set of luminescent layers. The layers are chosen to absorb the blue OLED emission and then luminescence with high efficiency at longer wavelengths. The composition and number of layers are chosen so that the unabsorbed blue emission and the longer wavelength re-emission combine to make white light. A downconversion approach has the advantage of allowing a wide variety of colors to be made from a limited set of blue emitters. In addition, one does not have to carefully tune the emission wavelength of the individual electro-luminescent species within the OLED device in order to achieve white light. The downconversion architecture used to develop the 15LPW large area light source consisted of a polymer-based blue-emitting OLED and three downconversion layers. Two of the layers utilized perylene based dyes from BASF AG of Germany with high quantum efficiency (>98%) and one of the layers consisted of inorganic phosphor particles (Y(Gd)AG:Ce) with a quantum efficiency of {approx}85%. By independently varying the optical density of the downconversion layers, the overall emission spectrum could be adjusted to maximize performance for lighting (e.g. blackbody temp

Joseph Shiang; James Cella; Kelly Chichak; Anil Duggal; Kevin Janora; Chris Heller; Gautam Parthasarathy; Jeffery Youmans; Joseph Shiang

2008-03-31T23:59:59.000Z

75

White LED with High Package Extraction Efficiency  

Office of Scientific and Technical Information (OSTI)

WHITE LED WITH HIGH PACKAGE WHITE LED WITH HIGH PACKAGE EXTRACTION EFFICIENCY Final Report Report Period Start Date: 10/01/2006 Report Period End Date: 09/30/2008 Authors: Yi Zheng and Matthew Stough Report Submission Date: November 2008 DOE Award Number: DE-FC26-06NT42935 Project Manager: Ryan Egidi OSRAM SYLVANIA Product Inc Central Research and Service Laboratory 71 Cherry Hill Dr., Beverly, MA 01915 2 DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor an agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus,

76

Novel Nanophosphors for High Efficiency Fluorescent Lamps  

SciTech Connect

This is the Final Report of the Novel Nanophosphors for High Efficiency Fluorescent Lamps, Department of Energy (DOE). The overall goal of this three-year program is to develop novel hybrid phosphors by coating commercially available lamp phosphors with highly stable wide band-gap nanocrystalline phosphors (NCP). The prime technical approach is the development of NCP quantum-splitting phosphor (QSP) and ultra-violet (UV) emitting phosphors with quantum efficiencies exceeding that of the conventional phosphors at 185 nm. The novel hybrid phosphors will increase the efficiency of the fluorescent lamps by up to 32%, enabling total energy savings of 0.26 quads, the reduction in the U.S. energy bill by $6.5 billion and the reduction of the annual carbon emission by 4.1 billion kilogram. Our work started by investigating through modeling calculations the requirement for the particle size of the NCP. Our work to develop suitable nanocrystalline phosphors started with the known oxide quantum splitting and UV emitting phosphors. We demonstrated several synthesis techniques for the production of high quality nanocrystalline materials that crystallizes in the desired phase and with the desired particle size. In collaboration with our subcontractor we demonstrated the feasibility for the manufacture of NC phosphors. We also demonstrated novel techniques of coating the NCP on the surface of micron sized phosphors. Our chief achievement pertains to the successful testing of the coated hybrid phosphor systems in linear fluorescent lamps. In linear fluorescent lamp tests, we have demonstrated up to 7% increase in the efficacy of hybrid phosphors over the conventional (uncoated) phosphors. We have also demonstrated the improvement in the lumen maintenance of the coated phosphors. A hybrid phosphor system based on the commercial red emitting phosphor, Y{sub 2}O{sub 3}:Eu{sup 3+} did not show the anticipated improvement in lamp efficacy. We explored the reasons for this observation, which are detailed in this report. Within the program we have carried out fundamental investigations into the physical processes that determine the quantum splitting behavior of the Pr{sup 3+} ion in solids. Specifically, we have investigated the quantum splitting luminescence of this ion in the LaPO{sub 4}, SrAl{sub 12}O{sub 19} and LiLaP{sub 4}O{sub 12} host lattices. In this final report we summarize the technical work completed under the Program, summarize our findings about the performance limits of the various technologies we investigated, and outline promising paths for future work.

Alok Srivatava

2007-03-31T23:59:59.000Z

77

Improving Real World Efficiency of High Performance Buildings  

E-Print Network (OSTI)

Improving Real World Efficiency of High Performance Buildings Buildings End-Use Energy Efficiency Research www.energy.ca.gov/research/buildings February 2012 The Issue Highperformance buildings efficiency in highperformance buildings, however, are not always realized in practice. Addressing

78

Highly Efficient Modeling of Dynamic Coronal Loops  

E-Print Network (OSTI)

Observational and theoretical evidence suggests that coronal heating is impulsive and occurs on very small cross-field spatial scales. A single coronal loop could contain a hundred or more individual strands that are heated quasi-independently by nanoflares. It is therefore an enormous undertaking to model an entire active region or the global corona. Three-dimensional MHD codes have inadequate spatial resolution, and 1D hydro codes are too slow to simulate the many thousands of elemental strands that must be treated in a reasonable representation. Fortunately, thermal conduction and flows tend to smooth out plasma gradients along the magnetic field, so "0D models" are an acceptable alternative. We have developed a highly efficient model called Enthalpy-Based Thermal Evolution of Loops (EBTEL) that accurately describes the evolution of the average temperature, pressure, and density along a coronal strand. It improves significantly upon earlier models of this type--in accuracy, flexibility, and capability. It ...

Klimchuk, J A; Cargill, P J

2007-01-01T23:59:59.000Z

79

High efficiency Brayton cycles using LNG  

DOE Patents (OSTI)

A modified, closed-loop Brayton cycle power conversion system that uses liquefied natural gas as the cold heat sink media. When combined with a helium gas cooled nuclear reactor, achievable efficiency can approach 68 76% (as compared to 35% for conventional steam cycle power cooled by air or water). A superheater heat exchanger can be used to exchange heat from a side-stream of hot helium gas split-off from the primary helium coolant loop to post-heat vaporized natural gas exiting from low and high-pressure coolers. The superheater raises the exit temperature of the natural gas to close to room temperature, which makes the gas more attractive to sell on the open market. An additional benefit is significantly reduced costs of a LNG revaporization plant, since the nuclear reactor provides the heat for vaporization instead of burning a portion of the LNG to provide the heat.

Morrow, Charles W. (Albuquerque, NM)

2006-04-18T23:59:59.000Z

80

White LED with High Package Extraction Efficiency  

Science Conference Proceedings (OSTI)

The goal of this project is to develop a high efficiency phosphor converting (white) Light Emitting Diode (pcLED) 1-Watt package through an increase in package extraction efficiency. A transparent/translucent monolithic phosphor is proposed to replace the powdered phosphor to reduce the scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is proposed between blue LED die and phosphor layer to recover inward yellow emission. At the end of the project we expect to recycle approximately 50% of the unrecovered backward light in current package construction, and develop a pcLED device with 80 lm/W{sub e} using our technology improvements and commercially available chip/package source. The success of the project will benefit luminous efficacy of white LEDs by increasing package extraction efficiency. In most phosphor-converting white LEDs, the white color is obtained by combining a blue LED die (or chip) with a powdered phosphor layer. The phosphor partially absorbs the blue light from the LED die and converts it into a broad green-yellow emission. The mixture of the transmitted blue light and green-yellow light emerging gives white light. There are two major drawbacks for current pcLEDs in terms of package extraction efficiency. The first is light scattering caused by phosphor particles. When the blue photons from the chip strike the phosphor particles, some blue light will be scattered by phosphor particles. Converted yellow emission photons are also scattered. A portion of scattered light is in the backward direction toward the die. The amount of this backward light varies and depends in part on the particle size of phosphors. The other drawback is that yellow emission from phosphor powders is isotropic. Although some backward light can be recovered by the reflector in current LED packages, there is still a portion of backward light that will be absorbed inside the package and further converted to heat. Heat generated in the package may cause a deterioration of encapsulant materials, affecting the performance of both the LED die and phosphor, leading to a decrease in the luminous efficacy over lifetime. Recent studies from research groups at Rensselaer Polytechnic Institute found that, under the condition to obtain a white light, about 40% of the light is transmitted outward of the phosphor layer and 60% of the light is reflected inward.1,2 It is claimed that using scattered photon extraction (SPE) technique, luminous efficacy is increased by 60%. In this project, a transparent/translucent monolithic phosphor was used to replace the powdered phosphor layer. In the normal pcLED package, the powdered phosphor is mixed with silicone either to be deposited on the top of LED die forming a chip level conversion (CLC) white LED or to be casted in the package forming a volume conversion white LED. In the monolithic phosphors there are no phosphor powder/silicone interfaces so it can reduce the light scattering caused by phosphor particles. Additionally, a multi-layer thin film selectively reflecting filter is inserted in the white LED package between the blue LED die and phosphor layer. It will selectively transmit the blue light from the LED die and reflect the phosphor's yellow inward emission outward. The two technologies try to recover backward light to the outward direction in the pcLED package thereby improving the package extraction efficiency.

Yi Zheng; Matthew Stough

2008-09-30T23:59:59.000Z

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81

Tailored Materials for High Efficiency CIDI Engines  

DOE Green Energy (OSTI)

The overall goal of the project, Tailored Materials for High Efficiency Compression Ignition Direct Injection (CIDI) Engines, is to enable the implementation of new combustion strategies, such as homogeneous charge compression ignition (HCCI), that have the potential to significantly increase the energy efficiency of current diesel engines and decrease fuel consumption and environmental emissions. These strategies, however, are increasing the demands on conventional engine materials, either from increases in peak cylinder pressure (PCP) or from increases in the temperature of operation. The specific objective of this project is to investigate the application of a new material processing technology, friction stir processing (FSP), to improve the thermal and mechanical properties of engine components. The concept is to modify the surfaces of conventional, low-cost engine materials. The project focused primarily on FSP in aluminum materials that are compositional analogs to the typical piston and head alloys seen in small- to mid-sized CIDI engines. Investigations have been primarily of two types over the duration of this project: (1) FSP of a cast hypoeutectic Al-Si-Mg (A356/357) alloy with no introduction of any new components, and (2) FSP of Al-Cu-Ni alloys (Alloy 339) by physically stirring-in various quantities of carbon nanotubes/nanofibers or carbon fibers. Experimental work to date on aluminum systems has shown significant increases in fatigue lifetime and stress-level performance in aluminum-silicon alloys using friction processing alone, but work to demonstrate the addition of carbon nanotubes and fibers into aluminum substrates has shown mixed results due primarily to the difficulty in achieving porosity-free, homogeneous distributions of the particulate. A limited effort to understand the effects of FSP on steel materials was also undertaken during the course of this project. Processed regions were created in high-strength, low-alloyed steels up to 0.5 in. deep that showed significant grain refinement and homogeneous microstructures favorable to increased fracture toughness and fatigue performance. The final tasks of the project demonstrated that the FSP concept can be applied to a relevant part geometry by fabricating diesel piston crowns with FSP regions applied selectively to the edge of the bowl rim. This area of the piston typically suffers from conditions at high PCP that cause severe thermal fatigue issues. It is expected that, given the data from coupon testing, the durability of pistons modified by FSP will allow much higher fatigue lifetime and potentially also greater resistance to elevated stress-level effects on fatigue.

Grant, G.J.; Jana, S.

2012-03-30T23:59:59.000Z

82

Highly Efficient Modeling of Dynamic Coronal Loops  

E-Print Network (OSTI)

Observational and theoretical evidence suggests that coronal heating is impulsive and occurs on very small cross-field spatial scales. A single coronal loop could contain a hundred or more individual strands that are heated quasi-independently by nanoflares. It is therefore an enormous undertaking to model an entire active region or the global corona. Three-dimensional MHD codes have inadequate spatial resolution, and 1D hydro codes are too slow to simulate the many thousands of elemental strands that must be treated in a reasonable representation. Fortunately, thermal conduction and flows tend to smooth out plasma gradients along the magnetic field, so "0D models" are an acceptable alternative. We have developed a highly efficient model called Enthalpy-Based Thermal Evolution of Loops (EBTEL) that accurately describes the evolution of the average temperature, pressure, and density along a coronal strand. It improves significantly upon earlier models of this type--in accuracy, flexibility, and capability. It treats both slowly varying and highly impulsive coronal heating; it provides the differential emission measure distribution, DEM(T), at the transition region footpoints; and there are options for heat flux saturation and nonthermal electron beam heating. EBTEL gives excellent agreement with far more sophisticated 1D hydro simulations despite using four orders of magnitude less computing time. It promises to be a powerful new tool for solar and stellar studies.

J. A. Klimchuk; S. Patsourakos; P. J. Cargill

2007-10-01T23:59:59.000Z

83

Design of a high activity and selectivity alcohol catalyst. [Design of a flow microreactor  

DOE Green Energy (OSTI)

Research on the design of a high selectivity alcohol catalyst continued. During the first quarter of this project, our goals have been to overhaul key experimental equipment used in the previous project, plan and design new equipment and to identify a person to carry out the research program. The flow microreactor, previously assembled, has been reactivated and major improvements have been made both to the reactor and its attendant analytical instrumentation. This equipment is described later in this report. In addition to this, a state-of-the-art hydrogen chemisorption instrument has been designed and the components for its construction have been ordered. Additionally, four recent publications by the principal investigators on the subject of this project have appeared. 3 figs.

Foley, H.C.; Mills, G.A.

1990-11-26T23:59:59.000Z

84

High efficiency photodetection below the quantum noise limit  

E-Print Network (OSTI)

Two low-noise, high quantum efficiency, high bandwidth photodetectors have constructed to form a balanced homodyne detector to detect squeezed light. The detectors have quantum efficiencies of 85% and 90%, a bandwidth of ...

Bullard, Elizabeth Caryn

2005-01-01T23:59:59.000Z

85

Mechanism of oxygen reduction reaction on transition metal oxide catalysts for high temperature fuel cells  

E-Print Network (OSTI)

The solid oxide fuel cell (SOFC) with its high energy conversion efficiency, low emissions, silent operation and its ability to utilize commercial fuels has the potential to create a large impact on the energy landscape. ...

La O', Gerardo Jose Cordova

2008-01-01T23:59:59.000Z

86

High Efficiency Organic Light Emitting Devices for Lighting  

SciTech Connect

Incorporate internal scattering layers and microlens arrays in high efficiency OLED to achieve up to 70% EQE.

So, Franky; Tansu, Nelson; Gilchrist, James

2013-06-30T23:59:59.000Z

87

High Efficiency Electrical Energy Storage Using Reversible Solid ...  

Science Conference Proceedings (OSTI)

Symposium, Energy Storage III: Materials, Systems and Applications Symposium. Presentation Title, High Efficiency Electrical Energy Storage Using Reversible ...

88

High Efficiency Low Emission Supermarket Refrigeration Research Project  

Energy.gov (U.S. Department of Energy (DOE))

The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies.

89

High efficiency stoichiometric internal combustion engine system  

DOE Patents (OSTI)

A power system including a stoichiometric compression ignition engine in which a roots blower is positioned in the air intake for the engine to control air flow. Air flow is decreased during part power conditions to maintain the air-fuel ratio in the combustion chamber of the engine at stoichiometric, thus enabling the use of inexpensive three-way catalyst to reduce oxides of nitrogen. The roots blower is connected to a motor generator so that when air flow is reduced, electrical energy is stored which is made available either to the roots blower to temporarily increase air flow or to the system electrical load and thus recapture energy that would otherwise be lost in reducing air flow.

Winsor, Richard Edward (Waterloo, IA); Chase, Scott Allen (Cedar Falls, IA)

2009-06-02T23:59:59.000Z

90

SUPPORTED LIQUID CATALYSTS FOR REMOVAL OF HIGH TEMPERATURE FUEL CELL CONTAMINANTS  

DOE Green Energy (OSTI)

A novel catalytic synthesis gas oxidation process using molten carbonate salts supported on compatible fluidized iron oxide particles (supported-liquid-phase-catalyst (SLPC) fluidized bed process) was investigated. This process combines the advantages of large scale fluidized bed processing with molten salt bath oxidation. Molten salt catalysts can be supported within porous fluidized particles in order to improve mass transfer rates between the liquid catalysts and the reactant gases. Synthesis gas can be oxidized at reduced temperatures resulting in low NO{sub x} formation while trace sulfides and halides are captured in-situ. Hence, catalytic oxidation of synthesis gas can be carried out simultaneously with hot gas cleanup. Such SLPC fluidized bed processes are affected by inter-particle liquid capillary forces that may lead to agglomeration and de-fluidization of the bed. An understanding of the origin and strength of these forces is needed so that they can be overcome in practice. Process design is based on thermodynamic free energy minimization calculations that indicate the suitability of eutectic Na{sub 2}CO{sub 3}/K{sub 2}CO{sub 3} mixtures for capturing trace impurities in-situ (< 1 ppm SO{sub x} released) while minimizing the formation of NO{sub x}(< 10 ppm). Iron oxide has been identified as a preferred support material since it is non-reactive with sodium, is inexpensive, has high density (i.e. inertia), and can be obtained in various particle sizes and porosities. Force balance modeling has been used to design a surrogate ambient temperature system that is hydrodynamically similar to the real system, thus allowing complementary investigation of the governing fluidization hydrodynamics. The primary objective of this research was to understand the origin of and to quantify the liquid capillary interparticle forces affecting the molten carbonate SLPC fluidized bed process. Substantial theoretical and experimental exploratory results indicate process feasibility. The potential environmental gain from success is enormous, impacting all areas of the world where coal is burned to supply steam or direct industrial heat. Project success may lead to an integrated combustion system providing for simultaneous catalytic oxidation and hot gas cleanup of raw synthesis gas from an upstream coal gasifier.

Alan W. Weimer (PI); Peter Czerpak; Patrick Hilbert

2000-01-01T23:59:59.000Z

91

Oxidation catalyst  

DOE Patents (OSTI)

The present invention generally relates to catalyst systems and methods for oxidation of carbon monoxide. The invention involves catalyst compositions which may be advantageously altered by, for example, modification of the catalyst surface to enhance catalyst performance. Catalyst systems of the present invention may be capable of performing the oxidation of carbon monoxide at relatively lower temperatures (e.g., 200 K and below) and at relatively higher reaction rates than known catalysts. Additionally, catalyst systems disclosed herein may be substantially lower in cost than current commercial catalysts. Such catalyst systems may be useful in, for example, catalytic converters, fuel cells, sensors, and the like.

Ceyer, Sylvia T. (Cambridge, MA); Lahr, David L. (Cambridge, MA)

2010-11-09T23:59:59.000Z

92

Highly Efficient Multigap Solar Cell Materials  

Scientists at Berkeley Lab have invented multiband gap semiconducting materials for developing solar cells that could achieve power conversion efficiencies of 50 percent or higher.

93

Mobile Source Air Toxics (MSATs) from High Efficiency Clean Combustion: Catalytic Exhaust Treatment Effects  

Science Conference Proceedings (OSTI)

High Efficiency Clean Combustion (HECC) strategies such as homogenous charge compression ignition (HCCI) and pre-mixed charge compression ignition (PCCI) offer much promise for the reduction of NOx and PM from diesel engines. While delivering low PM and low NOx, these combustion modes often produce much higher levels of CO and HC than conventional diesel combustion modes. In addition, partially oxygenated species such as formaldehyde (an MSAT) and other aldehydes increase with HECC modes. The higher levels of CO and HCs have the potential to compromise the performance of the catalytic aftertreatment, specifically at low load operating points. As HECC strategies become incorporated into vehicle calibrations, manufacturers need to avoid producing MSATs in higher quantities than found in conventional combustion modes. This paper describes research on two different HECC strategies, HCCI and PCCI. Engine-out data for several MSAT species (formaldehyde, acetaldehyde, benzene, toluene, ethylbenzene, xylenes, naphthalene, PAHs, diesel PM) as well as other HC species are presented and compared when possible with conventional operation. In addition, catalyst-out values were measured to assess the destruction of individual MSATs over the catalyst. At low engine loads, MSATs were higher and catalyst performance was poorer. Particle sizing results identify large differences between PM from conventional and HECC operation.

Storey, John Morse [ORNL; Lewis Sr, Samuel Arthur [ORNL; Parks, II, James E [ORNL; Barone, Teresa L [ORNL; Prikhodko, Vitaly Y [ORNL

2008-01-01T23:59:59.000Z

94

High efficiency, radiation-hard solar cells  

DOE Green Energy (OSTI)

The direct gap of the In{sub 1-x}Ga{sub x}N alloy system extends continuously from InN (0.7 eV, in the near IR) to GaN (3.4 eV, in the mid-ultraviolet). This opens the intriguing possibility of using this single ternary alloy system in single or multi-junction (MJ) solar cells of the type used for space-based surveillance satellites. To evaluate the suitability of In{sub 1-x}Ga{sub x}N as a material for space applications, high quality thin films were grown with molecular beam epitaxy and extensive damage testing with electron, proton, and alpha particle radiation was performed. Using the room temperature photoluminescence intensity as a indirect measure of minority carrier lifetime, it is shown that In{sub 1-x}Ga{sub x}N retains its optoelectronic properties at radiation damage doses at least 2 orders of magnitude higher than the damage thresholds of the materials (GaAs and GaInP) currently used in high efficiency MJ cells. This indicates that the In{sub 1-x}Ga{sub x}N is well-suited for the future development of ultra radiation-hard optoelectronics. Critical issues affecting development of solar cells using this material system were addressed. The presence of an electron-rich surface layer in InN and In{sub 1-x}Ga{sub x}N (0 < x < 0.63) was investigated; it was shown that this is a less significant effect at large x. Evidence of p-type activity below the surface in Mg-doped InN was obtained; this is a significant step toward achieving photovoltaic action and, ultimately, a solar cell using this material.

Ager III, J.W.; Walukiewicz, W.

2004-10-22T23:59:59.000Z

95

New and Underutilized Technology: Efficient High Bay Fluorescent Lighting |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Efficient High Bay Fluorescent Efficient High Bay Fluorescent Lighting New and Underutilized Technology: Efficient High Bay Fluorescent Lighting October 7, 2013 - 8:54am Addthis The following information outlines key deployment considerations for efficient high bay fluorescent lighting within the Federal sector. Benefits Efficient high bay fluorescent lighting can include either T5 or T8 fluorescent lighting systems for high-bay applications currently using metal halide fixtures. Fluorescent fixtures offer better light distribution, better light maintenance over the life of the lamp, improved color quality, and on-off control (re-strike time) with lower energy consumption. Application Efficient high bay fluorescent lighting is applicable for facilities containing high bay areas. Key Factors for Deployment

96

Catalyst system comprising a first catalyst system tethered to a supported catalyst  

DOE Patents (OSTI)

The present invention provides new catalyst formats which comprise a supported catalyst tethered to a second and different catalyst by a suitable tethering ligand. A preferred system comprises a heterogeneous supported metal catalyst tethered to a homogeneous catalyst. This combination of homogeneous and heterogeneous catalysts has a sufficient lifetime and unusually high catalytic activity in arene hydrogenations, and potentially many other reactions as well, including, but not limited to hydroformylation, hydrosilation, olefin oxidation, isomerization, hydrocyanation, olefin metathesis, olefin polymerization, carbonylation, enantioselective catalysis and photoduplication. These catalysts are easily separated from the products, and can be reused repeatedly, making these systems very economical.

Angelici, Robert J. (Ames, IA); Gao, Hanrong (Ames, IA)

1998-08-04T23:59:59.000Z

97

Hydroprocessing of solvent-refined coal: catalyst-screening results  

SciTech Connect

This report presents the results of screening four catalysts for hydroprocessing a 50 wt% mixture of SRC-I in a prehydrogenated creosote oil using a continuous flow unit. All catalysts employed were nickel-molybdates with varying properties. Reaction conditions were 2000 psi, 8 SCFH of hydrogen, volume hourly space velocity of 0.6 to 1.0 cc of SRC-I/hr/cc of catalyst, and 48 hours at 750/sup 0/F followed by 72 hours at 780/sup 0/F. The results indicate that the Shell 324 catalyst is best for hydrogenation of the feedstock but only marginally better than CB 81-44 for denitrogenation. The CB 81-44 catalyst may be slightly better than Shell 324 for the conversion of the +850/sup 0/F fraction of the feedstock. Desulfurization was uniformly high for all catalysts. Catalysts with a bimodal pore size distribution (i.e., SMR7-6137(1)) appear to be better for denitrogenation than unimodal catalysts (i.e., SMR7-6137(4)) containing the same metals loading. Unimodal catalysts (i.e., Shell 324) with higher metals loadings are comparable to bimodal catalysts (i.e., CB 81-44) containing less metals. The results indicate that pore size distribution and metals loading are important parameters for high activity. Catalysts with a unimodal pore volume distribution are capable of being restored to their original state, while bimodal ones experience a loss in surface area and pore volume and an increase in pellet density. This is attributed to the more efficient use of the interior surface area of the catalyst, which results in higher accumulation of coke and metals. Since coke can be removed via controlled oxidation, the irreversible loss is due to the higher concentrations of metals in the catalyst.

Stiegel, G.J.; Tischer, R.E.; Polinski, L.M.

1982-03-01T23:59:59.000Z

98

High efficiency pulse motor drive for robotic propulsion  

E-Print Network (OSTI)

The goal of this research is to improve the power efficiency of robotic locomotion through the use of series elastic actuation, with a focus on swimming motion. To achieve high efficiency, electromechanical drives need to ...

Sun, Zhen, M.S. Massachusetts Institute of Technology

2013-01-01T23:59:59.000Z

99

Techniques for high-efficiency outphasing power amplifiers  

E-Print Network (OSTI)

A trade-off between linearity and efficiency exists in conventional power amplifiers (PAs). The outphase amplifying concept overcomes this trade-off by enabling the use of high efficiency, non-linear power amplifiers for ...

Godoy, Philip (Philip Andrew)

2011-01-01T23:59:59.000Z

100

Energy efficiency indicators for high electric-load buildings  

Science Conference Proceedings (OSTI)

Energy per unit of floor area is not an adequate indicator for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed.

Aebischer, Bernard; Balmer, Markus A.; Kinney, Satkartar; Le Strat, Pascale; Shibata, Yoshiaki; Varone, Frederic

2003-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Design of high efficiency Mid IR QCL lasers  

E-Print Network (OSTI)

The proposed research is a study of designing high-efficiency Mid-IR quantum cascade lasers (QCL). This thesis explores "injector-less" designs for achieving lower voltage defects and improving wall plug efficiencies through ...

Hsu, Allen Long

2008-01-01T23:59:59.000Z

102

Nanostructured Water Oxidation Catalysts - Energy Innovation ...  

Nanostructured Cobalt Oxide Clusters in Mesoporous Silica as Efficient Oxygen-Evolving Catalysts. Angewandte Chemie International Edition. Vol. 28: ...

103

High-Resolution Structure of the Photosynthetic Mn4Ca Catalyst from X-ray Spectroscopy  

Science Conference Proceedings (OSTI)

The application of high-resolution X-ray spectroscopy methods to study the photosynthetic water oxidizing complex, which contains a unique hetero-nuclear catalytic Mn4Ca cluster, are described. Issues of X-ray damage especially at the metal sites in the Mn4Ca cluster are discussed. The structure of the Mn4Ca catalyst at high-resolution which has so far eluded attempts of determination by X-ray diffraction, EXAFS and other spectroscopic techniques has been addressed using polarized EXAFS techniques applied to oriented PS II membrane preparations and PS II single crystals. A review of how the resolution of traditional EXAFS techniques can be improved, using methods such as range-extended EXAFS is presented, and the changes that occur in the structure of the cluster as it advances through the catalytic cycle are described. X-ray absorption and emission techniques (XANES and K? emission) have been used earlier to determine the oxidation states of the Mn4Ca cluster, and in this report we review the use of X-ray resonant Raman spectroscopy to understand the electronic structure of the Mn4Ca cluster as it cycles through the intermediate S-states.

Yachandra, Vittal; Yano, Junko; Kern, Jan; Pushkar, Yulia; Sauer, Kenneth; Glatzel, Pieter; Bergmann, Uwe; Messinger, Johannes; Zouni, Athina; Yachandra, Vittal K.

2007-08-01T23:59:59.000Z

104

Application of In-Situ High Energy-Resolution Fluorescence Detection and Time-Resolved X-Ray Spectroscopy: Catalytic Activation of Oxygen over Supported Gold Catalysts  

SciTech Connect

Life-time-broadening reduction in high-energy-resolution fluorescence detected XAS produced spectra of unprecedented detail. Au L3 edge spectra of a Au/Al2O3 catalyst under various reaction conditions showed the interaction of oxygen with the gold particles on this catalyst. A reaction path on the gold particle in the oxidation of CO was established.

Bokhoven, Jeroen A. van [Institute for Chemical and Bioengineering, ETH Zurich (Switzerland); Tromp, Moniek [University of Southampton, School of Chemistry, Southampton (United Kingdom); Glatzel, Pieter; Safonova, Olga [European Synchrotron Radiation Facility, Grenoble (France)

2007-02-02T23:59:59.000Z

105

Method for generating a highly reactive plasma for exhaust gas after treatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

This patent application describes a method and apparatus of exhaust gas remediation that enhance the reactivity of the material catalysts found within catalytic converters of cars, trucks, and power stations.

Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

2000-07-01T23:59:59.000Z

106

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS  

E-Print Network (OSTI)

process efficiency (UoK, GA) · Estimate the size and cost of the process equipment (All) #12;s NERI H2 6 cycle analysis (SNL) · Develop detailed chemical flowsheet for selected process and determine projected UT-3 process is conceptually simple. . . l Invented at Univ. of Tokyo, being pursued in Japan, SI

107

Water Uptake in PEMFC Catalyst Layers  

E-Print Network (OSTI)

Water Uptake in PEMFC Catalyst Layers H. P. Gunterman, a A.membrane fuel-cell catalyst layers are characterized in thecurves indicate that the catalyst layers tested are highly

Gunterman, Haluna P.

2013-01-01T23:59:59.000Z

108

High Efficiency Low Emission Supermarket Refrigeration Research Project |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

High Efficiency Low Emission Supermarket High Efficiency Low Emission Supermarket Refrigeration Research Project High Efficiency Low Emission Supermarket Refrigeration Research Project The U.S. Department of Energy (DOE) is currently conducting research into high efficiency, low emission supermarket refrigeration technologies. Project Description The project involves the development of a supermarket refrigeration system that can reduce greenhouse gas emissions and energy consumption when compared to existing systems. The challenge is to design a system that is capable of achieving low refrigerant leak rates while significantly reducing both the energy consumption and the refrigerant charge size. Project Partners Research is being undertaken between DOE and Oak Ridge National Laboratory. Project Goals

109

Available Technologies: High Efficiency Spiral RF-Induction ...  

The spiral antennas efficient use of source geometry also ... Neutron and high energy gamma ... A typical RF-induction plasma generator with a ...

110

Titania Coated Silica Microspheres for High Efficiency Dye ...  

Science Conference Proceedings (OSTI)

These microspheres, if used in DSSCs, can boost the efficiency of solar cell ... In- situ Characterization of Intercalation-induced Damage of High Purity Graphite ...

111

Energy Efficiency in Mineral Processing Industry Using High ...  

Science Conference Proceedings (OSTI)

Presentation Title, Energy Efficiency in Mineral Processing Industry Using High ... These studies were prepared by Tetra Tech on eight different projects at ...

112

Low Cost, High Efficiency Tandem Silicon Solar Cells and LEDs  

Wladek Walukiewicz, Joel Ager, and Kin Man Yu of Berkeley Lab have developed high-efficiency solar cells that leverage the well-established design and ...

113

High-Efficiency Photovoltaics at Thin Film Costs  

Time (Years) 0-+ 5. 10. 15. 20. 25. Opportunity. Technology. ... • 15 years renewable energy business development ... High-Efficiency Photovoltaics at ...

114

Complex Oxides for Highly Efficient Solid-State Energy ...  

Complex Oxides for Highly Efficient Solid-State Energy ... Using complex oxides to directly convert thermal to electrical energy is both ... Thermal P ...

115

Available Technologies: High Quantum Efficiency Charge-Coupled ...  

Scientists at Berkeley Lab have developed a p-channel CCD with high quantum efficiency in the blue and near infrared wavelengths by combining a ...

116

Candidate Alloys for Cost-Effective, High-Efficiency, High ...  

Science Conference Proceedings (OSTI)

the efficiency of heat exchange in these fuel cells require both development and careful ..... 3rd EPRI Conference on Advances in Materials Technology for Fossil.

117

"Tuning" microalgae for high photosynthesis efficiency  

NLE Websites -- All DOE Office Websites (Extended Search)

"Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" microalgae for high photosynthesis efficiency Los Alamos scientist Richard Sayre and his team of researchers have recently developed more efficient microalgae. March 25, 2013 Shown here is a model for light absorption and use by algae as a function of antenna size. Shown here is a model for light absorption and use by algae as a function of antenna size. The team's work in this area is reported in a paper published in the journal Algal Research. Los Alamos scientist Richard Sayre of Bioenergy and Biome Sciences (B-11) and his team of researchers have recently developed more efficient microalgae. Microalgae have large rates of biomass accumulation due to their high photosynthetic efficiencies. This makes them attractive candidates for

118

"Tuning" microalgae for high photosynthesis efficiency  

NLE Websites -- All DOE Office Websites (Extended Search)

"Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" microalgae for high photosynthesis efficiency Los Alamos scientist Richard Sayre and his team of researchers have recently developed more efficient microalgae. March 25, 2013 Shown here is a model for light absorption and use by algae as a function of antenna size. Shown here is a model for light absorption and use by algae as a function of antenna size. The team's work in this area is reported in a paper published in the journal Algal Research. Los Alamos scientist Richard Sayre of Bioenergy and Biome Sciences (B-11) and his team of researchers have recently developed more efficient microalgae. Microalgae have large rates of biomass accumulation due to their high photosynthetic efficiencies. This makes them attractive candidates for

119

Project Catalyst | Open Energy Information  

Open Energy Info (EERE)

Project Catalyst Project Catalyst Jump to: navigation, search Name Project Catalyst Agency/Company /Organization ClimateWorks, European Climate Foundation Sector Climate, Energy, Land Focus Area Energy Efficiency, Forestry Website http://www.project-catalyst.in References Project Catalyst[1] Project Catalyst Screenshot Contents 1 About 2 Resources 2.1 Tools 2.2 Programs 3 References About "Project Catalyst is an initiative of the ClimateWorks Foundation. ClimateWorks is a global, nonprofit philanthropic foundation headquartered in San Francisco, California with a network of affiliated foundations in China, India, the US, and the European Union. The ClimateWorks family of organizations focus on enacting policies that reduce greenhouse gas emissions through three general policy areas: energy efficiency standards,

120

Cr-free Fe-based metal oxide catalysts for high temperature water gas shift reaction of fuel processor using LPG  

Science Conference Proceedings (OSTI)

The goal of this study was to identify the most suitable chromium-free iron-based catalysts for the HTS (high temperature shift) reaction of a fuel processor using LPG. Hexavalent chromium (Cr6+) in the commercial HTS catalyst has been regarded as hazardous material. We selected Ni and Co as the substitution for chromium in the Fe-based HTS catalyst and investigated the HTS activities of these Crfree catalysts at LPG reformate condition. Cr-free Fe-based catalysts which contain Ni, Zn, or Co instead of Cr were prepared by coprecipitation method and the performance of the catalysts in HTS was evaluated under gas mixture conditions (42% H2, 10% CO, 37% H2O, 8% CO2, and 3% CH4; R (reduction factor): about 1.2) similar to the gases from steam reforming of LPG (100% conversion at steam/carbon ratio = 3), which is higher than R (under 1) of typically studied LNG reformate condition. Among the prepared Cr-free Febased catalysts, the 5 wt%-Co/Fe/20 wt%-Ni and 5 wt%-Zn/Fe/20 wt%-Ni catalysts showed good catalytic activity under this reaction condition simulating LPG reformate gas.

lee, Joon Y.; Lee, Dae-Won; Lee, Kwan Young; Wang, Yong

2009-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Compact and highly efficient laser pump cavity  

SciTech Connect

A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

Chang, Jim J. (Dublin, CA); Bass, Isaac L. (Castro Valley, CA); Zapata, Luis E. (Livermore, CA)

1999-01-01T23:59:59.000Z

122

Compact and highly efficient laser pump cavity  

SciTech Connect

A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

Chang, J.J.; Bass, I.L.; Zapata, L.E.

1999-11-02T23:59:59.000Z

123

Production of Mixed Alcohols from Bio-syngas over Mo-based Catalyst  

Science Conference Proceedings (OSTI)

A series of Mo-based catalysts prepared by sol-gel method using citric acid as complexant were successfully applied in the high efficient production of mixed alcohols from bio-syngas

Song-bai Qiu; Wei-wei Huang; Yong Xu; Lu Liu; Quan-xin Li

2011-01-01T23:59:59.000Z

124

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

125

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

126

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Nanoscale Chemical Imaging of a Working Catalyst Nanoscale Chemical Imaging of a Working Catalyst Print Wednesday, 28 January 2009 00:00 The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

127

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

128

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

129

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

130

Nanoscale Chemical Imaging of a Working Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Nanoscale Chemical Imaging of a Working Catalyst Print Nanoscale Chemical Imaging of a Working Catalyst Print The heterogeneous catalysts used in most chemical processes typically consist of nanoscale metal or metal oxide particles dispersed on high-surface-area supports. While these particles are the active elements of the catalyst, the overall performance depends not only on their size and composition but also on their multiple interactions with the support, reactants, and products. Probing this chemical soup in real time under realistic reaction conditions is such a tall order that in some cases even the catalytically active chemical species is not known. A Dutch team working at the ALS has combined scanning transmission x-ray microscopy with a reaction chamber adapted from electron microscopy to identify the chemical species present for an iron-based Fischer-Tropsch synthesis catalyst and to image their distribution on the nanoscale. When developed further, this new tool may give chemists the ability to design and tailor catalysts for maximum selectivity and efficiency in a wide range of chemical processes.

131

Highly Energy Efficient Wall Systems Research Project | Department of  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Highly Energy Efficient Wall Systems Highly Energy Efficient Wall Systems Research Project Highly Energy Efficient Wall Systems Research Project The Department of Energy is currently conducting research into highly energy efficient wall systems. Walls with high R-values are better insulators, and their development can help buildings come closer to having zero net energy consumption. Project Description This project seeks to develop a commercially viable wall system up to R-40 through integration of vacuum technology with the exterior insulated façade system (EIFS). Dow Corning will develop a wall system configuration of expanded polystyrene vacuum isolation panels that can be specified for R-values of 20, 30, and 40. This project also aims to develop a unitized protection system of vacuum isolation panels and to validate current code

132

Department of Energy Lauds Highly Efficient Industrial Technology |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Lauds Highly Efficient Industrial Technology Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology November 30, 2007 - 4:45pm Addthis DOE Celebrates One-Year Anniversary of Operation of the Energy Efficient "Super Boiler" WASHINGTON, DC - Representing important technology transfer from Department of Energy (DOE) labs to the marketplace, DOE today announced the successful one-year operation of the first generation "Super Boiler," which can deliver 94 percent thermal efficiency, while producing fewer emissions than conventional boiler technologies. By 2020, this technology could save more than 185 trillion British Thermal Units (Btus) of energy - equivalent to the natural gas consumed by more than two million households. The

133

Department of Energy Lauds Highly Efficient Industrial Technology |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Department of Energy Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology Department of Energy Lauds Highly Efficient Industrial Technology November 30, 2007 - 4:45pm Addthis DOE Celebrates One-Year Anniversary of Operation of the Energy Efficient "Super Boiler" WASHINGTON, DC - Representing important technology transfer from Department of Energy (DOE) labs to the marketplace, DOE today announced the successful one-year operation of the first generation "Super Boiler," which can deliver 94 percent thermal efficiency, while producing fewer emissions than conventional boiler technologies. By 2020, this technology could save more than 185 trillion British Thermal Units (Btus) of energy - equivalent to the natural gas consumed by more than two million households. The

134

Energy Efficiency Indicators for High Electric-Load Buildings  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Efficiency Indicators for High Electric-Load Buildings Energy Efficiency Indicators for High Electric-Load Buildings Speaker(s): Bernard Aebischer Date: February 6, 2003 - 12:00pm Location: Bldg. 90 Seminar Host/Point of Contact: Kristina LaCommare Energy per unit of floor area is not an adequate indictor for energy efficiency in high electric-load buildings. For two activities, restaurants and computer centres, alternative indicators for energy efficiency are discussed. Prerequisites in order to be able to use these indicators in energy efficiency programmes are discussed. The opportunity of an internationally coordinated research activity is also presented. Since 1999, Dr. Bernard Aebischer has served as a senior scientist at CEPE (Centre for Energy Policy and Economics) of the Swiss Federal Institutes of

135

Improving efficiency of high-concentrator photovoltaics by cooling with  

NLE Websites -- All DOE Office Websites (Extended Search)

Improving efficiency of high-concentrator photovoltaics by cooling with Improving efficiency of high-concentrator photovoltaics by cooling with two-phase forced convection Title Improving efficiency of high-concentrator photovoltaics by cooling with two-phase forced convection Publication Type Journal Article Year of Publication 2010 Authors Ho, Tony, Samuel S. Mao, and Ralph Greif Journal International Journal of Energy Research Volume 34 Start Page 1257 Issue 14 Pagination 1257-1271 Date Published 11/2010 Keywords high-concentrator photovoltaic efficiency, two-phase flow cooling applications Abstract The potential of increasing high-concentrator photovoltaic cell efficiency by cooling with two-phase flow is analyzed. The governing energy equations were used to predict cell temperature distributions and cell efficiencies for a photovoltaic cell under 100 suns' concentration. Several design conditions were taken into consideration in the analysis, including cooling channel height, working fluid type (between water and R134a), working fluid inlet temperature, pressure, and mass flow rate. It was observed that the dominant parameter for increasing cell efficiency was the working fluid saturation temperature, which itself is affected by a number of the aforementioned design parameters. The results show R134a at low inlet pressures to be highly effective in this two-phase cooling design.

136

III-V High-Efficiency Multijunction Photovoltaics (Fact Sheet)  

Science Conference Proceedings (OSTI)

Capabilities fact sheet that includes scope, core competencies and capabilities, and contact/web information for III-V High-Efficiency Multijunction Photovoltaics at the National Center for Photovoltaics.

Not Available

2011-06-01T23:59:59.000Z

137

Durable and Highly Efficient Energy-harvesting Electrochromic ...  

Science Conference Proceedings (OSTI)

The resulting device performed three states: solar cell, transparent, and dark, and ... Anatase Nanostructures for High Efficiency Photocatalysis Application ... EBSD Study of Electromigration Damage in Idealized SnAgCu 305 Interconnects.

138

Energy Efficiency Indicators for High Electric-Load Buildings  

NLE Websites -- All DOE Office Websites (Extended Search)

Energy Efficiency Indicators for High Electric-Load Buildings Speaker(s): Bernard Aebischer Date: February 6, 2003 - 12:00pm Location: Bldg. 90 Seminar HostPoint of Contact:...

139

Conversion efficiency, scaling and global optimization of high harmonic generation  

E-Print Network (OSTI)

Closed form expressions for the high harmonic generation (HHG) conversion efficiency in the plateau and cut-off region are derived showing agreement with previous observations. Application of these results to optimal ...

Falcao-Filho, Edilson L.

140

City of High Point Electric- Residential Energy Efficiency Rebate Program  

Energy.gov (U.S. Department of Energy (DOE))

The City of High Point offers the Hometown Green Program to help customers reduce energy use. Under this program, rebates are available for newly constructed energy efficient homes, heat pumps, and...

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Highly efficient blue polyfluorene-based polymer light-emitting...  

NLE Websites -- All DOE Office Websites (Extended Search)

of Physics Volume 42 Pagination 5 Abstract A highly efficient blue polymer light-emitting diode based on poly(9,9-di(2-(2-(2-methoxy-ethoxy)ethoxy)ethyl)fluorenyl-2,7-diyl)...

142

High Energy Resolution Fluorescence Detection X-Ray Absorption Spectroscopy: Detection of Adsorption Sites in Supported Metal Catalysts  

Science Conference Proceedings (OSTI)

High energy resolution fluorescence detection (HERFD) X-ray adsorption spectroscopy (XAS) is demonstrated as a new tool to identify the geometry of metal adsorption sites and the orbitals involved in bonding. The type of CO adsorption site on a nanoparticular Pt-Al2O3 catalyst is determined. The orbitals involved in the Pt - CO bonding are identified using theoretical FEFF8.0 calculations. In situ application of HERFD XAS is applicable to a large number of catalytic systems and will provide fundamental insights in structure - performance relationships.

Tromp, Moniek [University of Southampton, School of Chemistry, Highfield, Southampton, SO17 1BJ (United Kingdom); Bokhoven, Jeroen A. van [Institute for chemical and bioengineering ETH Zurich (Switzerland); Safonova, Olga V.; Glatzel, Pieter [ESRF, Grenoble (France); Groot, Frank M. F. de [Utrecht University, Utrecht (Netherlands); Evans, John [University of Southampton, School of Chemistry, Highfield, Southampton, SO17 1BJ (United Kingdom); Diamond Light Source, Didcot (United Kingdom)

2007-02-02T23:59:59.000Z

143

Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials |  

Office of Science (SC) Website

Design of Bulk Nanocomposites as High Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Energy Frontier Research Centers (EFRCs) EFRCs Home Centers Research Science Highlights Highlight Archives News & Events Publications Contact BES Home 04.27.12 Design of Bulk Nanocomposites as High Efficiency Thermoelectric Materials Print Text Size: A A A RSS Feeds FeedbackShare Page Scientific Achievement A newly synthesized bulk thermoelectric material that contains nanocrystals with the same orientation and structure as the host material breaks thermoelectric efficiency records by blocking thermal, but not electrical, conductivity. Significance and Impact A new strategy to design inexpensive materials that more efficiently convert heat to electricity. Research Details Thermoelectric materials directly generate electrical power from heat, but

144

Laclede Gas Company - Residential High Efficiency Heating Rebate Program |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Residential High Efficiency Heating Rebate Residential High Efficiency Heating Rebate Program Laclede Gas Company - Residential High Efficiency Heating Rebate Program < Back Eligibility Multi-Family Residential Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Appliances & Electronics Water Heating Maximum Rebate Heating System: 2 maximum Programmable Thermostats: 2 maximum Multi-Family Property Owners: 50 thermostat rebates, 50 furnace rebates over the life of the program Program Info State Missouri Program Type Utility Rebate Program Rebate Amount Gas Furnace: $150 - $200 Gas Boiler: $150 Programmable Setback Thermostat: $25 Gas Water Heater: $50 - $200 Provider Laclede Gas Company Laclede Gas Company offers various rebates to residential customers for investing in energy efficient equipment and appliances. Residential

145

ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS  

SciTech Connect

Fischer-Tropsch (FT) synthesis to convert syngas (CO + H{sub 2}) derived from natural gas or coal to liquid fuels and wax is a well-established technology. For low H{sub 2} to CO ratio syngas produced from CO{sub 2} reforming of natural gas or from gasification of coal, the use of Fe catalysts is attractive because of their high water gas shift activity in addition to their high FT activity. Fe catalysts are also attractive due to their low cost and low methane selectivity. Because of the highly exothermic nature of the FT reaction, there has been a recent move away from fixed-bed reactors toward the development of slurry bubble column reactors (SBCRs) that employ 30 to 90 {micro}m catalyst particles suspended in a waxy liquid for efficient heat removal. However, the use of FeFT catalysts in an SBCR has been problematic due to severe catalyst attrition resulting in fines that plug the filter employed to separate the catalyst from the waxy product. Fe catalysts can undergo attrition in SBCRs not only due to vigorous movement and collisions but also due to phase changes that occur during activation and reaction.

K. Jothimurugesan; James G. Goodwin, Jr.; Santosh K. Gangwal

1999-10-01T23:59:59.000Z

146

Principles of energy efficiency in high performance computing  

Science Conference Proceedings (OSTI)

High Performance Computing (HPC) is a key technology for modern researchers enabling scientific advances through simulation where experiments are either technically impossible or financially not feasible to conduct and theory is not applicable. However, ... Keywords: HPC, PUE, energy efficiency, high performance computing, power usage effectiveness

Axel Auweter; Arndt Bode; Matthias Brehm; Herbert Huber; Dieter Kranzlmüller

2011-08-01T23:59:59.000Z

147

High Efficiency Solar Power via Separated Photo and Voltaic Pathways  

DOE Green Energy (OSTI)

This project demonstrates a novel nanostructured solar cell architecture capable of achieving high efficiency levels that is relatively simple and inexpensive to manufacture. The high efficiency will be achieved by the novel structure that separates the path of the photons from the path of the generated charge carriers. In this way, the photon path can be long for maximum light absorption, while the path for carriers can be short for maximum electronic energy harvesting. The combination of maximum light absorption coupled with maximum carrier harvesting is the basis for the expected high efficiency. The project will develop high efficiency solar cell prototypes utilizing this unique nanostructured architecture. The project addresses the fundamental limitation inherent in all current solar cell designs, and which opens a pathway to development for high efficiency solar cells at low cost. Realizing this goal will result in a levelized cost of electricity in the range of 10¢/kWh, which would achieve the long-sought goal of making photovoltaic electricity cost competitive with fossil-fuel generated electricity without any governmental subsidies. This breakthrough would spur the already rapid growth in the photovoltaic industry to an explosive pace, with significant, widespread benefit to the national economy and the nation’s energy security. The initial target of the program is to develop single-junction solar cells using ultrathin amorphous silicon with the performance approaching that of single crystal silicon cells.

Michael J. Naughton

2009-02-17T23:59:59.000Z

148

High Efficiency Adsorption Chillers: High Efficiency Adsorption Cooling Using Metal Organic Heat Carriers  

SciTech Connect

BEETIT Project: PNNL is incorporating significant improvements in materials that adsorb liquids or gases to design more efficient adsorption chillers. An adsorption chiller is a type of air conditioner that is powered by heat, solar or waste heat, or combustion of natural gas. Unlike typical chillers, this type has few moving parts and uses almost no electricity to operate. PNNL is designing adsorbent materials at the molecular level with at least 3 times higher refrigerant capacity and up to 20 times faster kinetics than adsorbents used in current chillers. By using the new adsorbent, PNNL is able to create a chiller that is significantly smaller, has twice the energy efficiency, and lower costs for materials and assembly time compared to conventional adsorption chillers.

None

2010-10-01T23:59:59.000Z

149

Laser Catalyst  

INL’s Laser Catalyst is a method for removing contaminant matter from a porous material. A polymer material is applied to a contaminated surface and ...

150

Home Performance with Energy Star High Efficiency Measure Incentive (HEMI)  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Home Performance with Energy Star High Efficiency Measure Incentive Home Performance with Energy Star High Efficiency Measure Incentive (HEMI) Home Performance with Energy Star High Efficiency Measure Incentive (HEMI) < Back Eligibility Residential Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Cooling Appliances & Electronics Sealing Your Home Ventilation Manufacturing Commercial Lighting Lighting Water Heating Maximum Rebate $3,000 Program Info State New York Program Type State Rebate Program Rebate Amount 10% of project costs Provider New York State Energy Research and Development Authority The New York State Research and Development Authority (NYSERDA) offers an incentive for homeowners of 1-4 homes that participate in the Home Performance with Energy Star program. The program entitles the participant

151

A high-efficiency thermoelectric converter for space applications  

DOE Green Energy (OSTI)

This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.

Metzger, J.D. [Westinghouse Savannah River Co., Aiken, SC (United States); El-Genk, M.S. [New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies

1990-12-31T23:59:59.000Z

152

A high-efficiency thermoelectric converter for space applications  

DOE Green Energy (OSTI)

This paper presents a concept for using high-temperature superconducting materials in thermoelectric generators (SCTE) to produce electricity at conversion efficiencies approaching 50% of the Carrot efficiency. The SCTE generator is applicable to systems operating in temperature ranges of high-temperature superconducting materials and thus would be a low-grade converter. Operating in cryogenic temperature ranges provides the advantage of inherently increasing the limits of the Carrot efficiency. Potential applications are for systems operating in space where the ambient temperatures are in the cryogenic temperature range. The advantage of using high-temperature superconducting material in a thermoelectric converter is that it would significantly reduce or eliminate the Joule heating losses in a thermoelectric element. This paper investigates the system aspects and the material requirements of the SCTE converter concept, and presents a conceptual design and an application for a space power system.

Metzger, J.D. (Westinghouse Savannah River Co., Aiken, SC (United States)); El-Genk, M.S. (New Mexico Univ., Albuquerque, NM (United States). Inst. for Space Nuclear Power Studies)

1990-01-01T23:59:59.000Z

153

Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Southwest Gas Corporation - Commercial High-Efficiency Equipment Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate Program Southwest Gas Corporation - Commercial High-Efficiency Equipment Rebate Program < Back Eligibility Commercial Industrial Savings Category Other Appliances & Electronics Commercial Weatherization Commercial Heating & Cooling Water Heating Maximum Rebate General: 50% of price Boiler Steam Trap: 25% of price Program Info State Arizona Program Type Utility Rebate Program Rebate Amount Modulating Burner Control: $10,000 Boiler O2 Trim Control Pad: $10,000 Boiler Steam Trap: $250 Non-condensing Boiler: $1/MBtuh Condensing Boiler: $1.25/MBtuh Storage Water Heater: 50% of cost, up to $1,100 Tankless Water Heater: 50% of cost, up to $450 Griddle: 50% of cost, up to $600 Fryer: 50% of cost, up to $1,350

154

High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells  

E-Print Network (OSTI)

of a triple cell showing 10.7% stable efficiency. Figure 4-1 Schematic diagram of the Hot Wire CVD deposition. Task 7: High-rate deposition of a-Si based solar cells We have conducted extensive research using a hot1 High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells PHASE I Annual

Deng, Xunming

155

High efficiency III-nitride light-emitting diodes  

DOE Patents (OSTI)

Tailored doping of barrier layers enables balancing of the radiative recombination among the multiple-quantum-wells in III-Nitride light-emitting diodes. This tailored doping enables more symmetric carrier transport and uniform carrier distribution which help to reduce electron leakage and thus reduce the efficiency droop in high-power III-Nitride LEDs. Mitigation of the efficiency droop in III-Nitride LEDs may enable the pervasive market penetration of solid-state-lighting technologies in high-power lighting and illumination.

Crawford, Mary; Koleske, Daniel; Cho, Jaehee; Zhu, Di; Noemaun, Ahmed; Schubert, Martin F; Schubert, E. Fred

2013-05-28T23:59:59.000Z

156

Epoxidation catalyst and process  

DOE Patents (OSTI)

Disclosed herein is a catalytic method of converting alkenes to epoxides. This method generally includes reacting alkenes with oxygen in the presence of a specific silver catalyst under conditions suitable to produce a yield of the epoxides. The specific silver catalyst is a silver nanocrystal having a plurality of surface planes, a substantial portion of which is defined by Miller indices of (100). The reaction is performed by charging a suitable reactor with this silver catalyst and then feeding the reactants to the reactor under conditions to carry out the reaction. The reaction may be performed in batch, or as a continuous process that employs a recycle of any unreacted alkenes. The specific silver catalyst has unexpectedly high selectivity for epoxide products. Consequently, this general method (and its various embodiments) will result in extraordinarily high epoxide yields heretofore unattainable.

Linic, Suljo (Ann Arbor, MI); Christopher, Phillip (Ann Arbor, MI)

2010-10-26T23:59:59.000Z

157

Low Cost, High Efficiency, High Pressure Hydrogen Storage  

DOE Green Energy (OSTI)

A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of $4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal.

Mark Leavitt

2010-03-31T23:59:59.000Z

158

Bandgap Engineering in High-Efficiency Multijunction Concentrator Cells  

DOE Green Energy (OSTI)

This paper discusses semiconductor device research paths under investigation with the aim of reaching the milestone efficiency of 40%. A cost analysis shows that achieving very high cell efficiencies is crucial for the realization of cost-effective photovoltaics, because of the strongly leveraging effect of efficiency on module packaging and balance-of systems costs. Lattice-matched (LM) GaInP/ GaInAs/ Ge 3-junction cells have achieved the highest independently confirmed efficiency at 175 suns, 25?C, of 37.3% under the standard AM1.5D, low-AOD terrestrial spectrum. Lattice-mismatched, or metamorphic (MM), materials offer still higher potential efficiencies, if the crystal quality can be maintained. Theoretical efficiencies well over 50% are possible for a MM GaInP/ 1.17-eV GaInAs/ Ge 3-junction cell limited by radiative recombination at 500 suns. The bandgap - open circuit voltage offset, (Eg/q) - Voc, is used as a valuable theoretical and experimental tool to characterize multijunction cells with subcell bandgaps ranging from 0.7 to 2.1 eV. Experimental results are presented for prototype 6-junction cells employing an active {approx}1.1-eV dilute nitride GaInNAs subcell, with active-area efficiency greater than 23% and over 5.3 V open-circuit voltage under the 1-sun AM0 space spectrum. Such cell designs have theoretical efficiencies under the terrestrial spectrum at 500 suns concentration exceeding 55% efficiency, even for lattice-matched designs.

King, R. R.; Sherif, R. A.; Kinsey, G. S.; Kurtz, S.; Fetzer, C. M.; Edmondson, K. M.; Law, D. C.; Cotal, H. L.; Krut, D. D.; Ermer, J. H.; Karam, N. H.

2005-08-01T23:59:59.000Z

159

Properties of High Efficiency CIGS Thin Film Solar Cells  

DOE Green Energy (OSTI)

We present experimental results in three areas. Solar cells with an efficiency of 19% have been fabricated with an absorber bandgap in the range of 1.1-1.2 eV. Properties of solar cells fabricated with and without an undoped ZnO layer were compared. The data show that high efficiency cells can be fabricated without using the high-resistivity or undoped ZnO layer. Properties of CIGS solar cells were fabricated from thin absorbers (1 {micro}m) deposited by the three-stage process and simultaneous co-deposition of all the elements. In both cases, solar cells with efficiencies of 16%-17% are obtained.

Ramanathan, K.; Keane, J.; Noufi, R.

2005-02-01T23:59:59.000Z

160

Desalination of seawater using a high-efficiency jet ejector  

E-Print Network (OSTI)

The ability to produce potable water economically is the primary focus of seawater desalination research. There are numerous methods to desalinate water, including reverse osmosis, multi-stage flash distillation, and multi-effect evaporation. These methods cost more than potable water produced from natural resources; hence an attempt is made in this research project to produce potable water using a modified high-efficiency jet ejector in vapor-compression distillation. The greater efficiency of the jet ejector is achieved by properly mixing propelled and motive streams. From experiments conducted using air, the pressure rise across the jet ejector is better in case of one or two mixing vanes and the highest back pressure (pinch valve closed 83.33%). At other pinch valve closings, the air velocity through the jet ejector was high, so the extra surface area from the mixing vanes caused excessive friction and lowered the efficiency.

Vishwanathappa, Manohar D.

2003-05-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
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161

Oxyhydrochlorination catalyst  

DOE Patents (OSTI)

An improved catalyst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HCl and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride.

Taylor, Charles E. (Pittsburgh, PA); Noceti, Richard P. (Pittsburgh, PA)

1992-01-01T23:59:59.000Z

162

Catalytic Synthesis of Oxygenates: Mechanisms, Catalysts and Controlling Characteristics  

DOE Green Energy (OSTI)

This research focused on catalytic synthesis of unsymmetrical ethers as a part of a larger program involving oxygenated products in general, including alcohols, ethers, esters, carboxylic acids and their derivatives that link together environmentally compliant fuels, monomers, and high-value chemicals. The catalysts studied here were solid acids possessing strong Br�������¸nsted acid functionalities. The design of these catalysts involved anchoring the acid groups onto inorganic oxides, e.g. surface-grafted acid groups on zirconia, and a new class of mesoporous solid acids, i.e. propylsulfonic acid-derivatized SBA-15. The former catalysts consisted of a high surface concentration of sulfate groups on stable zirconia catalysts. The latter catalyst consists of high surface area, large pore propylsulfonic acid-derivatized silicas, specifically SBA-15. In both cases, the catalyst design and synthesis yielded high concentrations of acid sites in close proximity to one another. These materials have been well-characterization in terms of physical and chemical properties, as well as in regard to surface and bulk characteristics. Both types of catalysts were shown to exhibit high catalytic performance with respect to both activity and selectivity for the bifunctional coupling of alcohols to form ethers, which proceeds via an efficient SN2 reaction mechanism on the proximal acid sites. This commonality of the dual-site SN2 reaction mechanism over acid catalysts provides for maximum reaction rates and control of selectivity by reaction conditions, i.e. pressure, temperature, and reactant concentrations. This research provides the scientific groundwork for synthesis of ethers for energy applications. The synthesized environmentally acceptable ethers, in part derived from natural gas via alcohol intermediates, exhibit high cetane properties, e.g. methylisobutylether with cetane No. of 53 and dimethylether with cetane No. of 55-60, or high octane properties, e.g. diisopropylether with blending octane No. of 105, and can replace aromatics in liquid fuels.

Kamil Klier; Richard G. Herman

2005-11-30T23:59:59.000Z

163

Catalyst-assisted Probabilistic Entanglement Transformation  

E-Print Network (OSTI)

We are concerned with catalyst-assisted probabilistic entanglement transformations. A necessary and sufficient condition is presented under which there exist partial catalysts that can increase the maximal transforming probability of a given entanglement transformation. We also design an algorithm which leads to an efficient method for finding the most economical partial catalysts with minimal dimension. The mathematical structure of catalyst-assisted probabilistic transformation is carefully investigated.

Yuan Feng; Runyao Duan; Mingsheng Ying

2004-04-27T23:59:59.000Z

164

Area-efficient high-throughput MAP decoder architectures  

Science Conference Proceedings (OSTI)

Iterative decoders such as turbo decoders have become integral components of modern broadband communication systems because of their ability to provide substantial coding gains. A key computational kernel in iterative decoders is the maximum a posteriori ... Keywords: area efficient, block-interleaved pipelining, high throughput, parallel processing, pipeline, symbol-based decoding, turbo decoder, turbo equalizer

Seok-Jun Lee; Naresh R. Shanbhag; Andrew C. Singer

2005-08-01T23:59:59.000Z

165

Motor voltage high harmonics influence to efficient energy usage  

Science Conference Proceedings (OSTI)

Analysis of the effect of non-sinusoidal voltages on the three-phase induction motor is presented in the paper. When the induction motors are supplied by a rectangular shape of the voltage inverter with high levels of harmonic voltage (Uh,i ... Keywords: energy efficiency, harmonics, induction motor, non-sinusoidal voltage, power losses

Miloje M. Kostic; Branka B. Kostic

2011-07-01T23:59:59.000Z

166

Basic studies of 3-5 high efficiency cell components  

DOE Green Energy (OSTI)

This project's objective is to improve our understanding of the generation, recombination, and transport of carriers within III-V homo- and heterostructures. The research itself consists of fabricating and characterizing solar cell building blocks'' such as junctions and heterojunctions as well as basic measurements of material parameters. A significant effort is also being directed at characterizing loss mechanisms in high-quality, III-V solar cells fabricated in industrial research laboratories throughout the United States. The project's goal is to use our understanding of the device physics of high-efficiency cell components to maximize cell efficiency. A related goal is the demonstration of new cell structures fabricated by molecular beam epitaxy (MBE). The development of measurement techniques and characterization methodologies is also a project objective. This report describes our progress during the fifth and final year of the project. During the past five years, we've teamed a great deal about heavy doping effects in p[sup +] and n[sup +] GaAs and have explored their implications for solar cells. We have developed an understanding of the dominant recombination losses in present-day, high-efficiency cells. We've learned to appreciated the importance of recombination at the perimeter of the cell and have developed techniques for chemically passivating such edges. Finally, we've demonstrated that films grown by molecular beam epitaxy are suitable for high-efficiency cell research.

Lundstrom, M.S.; Melloch, M.R.; Pierret, R.F.; Carpenter, M.S.; Chuang, H.L.; Dodd, P.E.; Keshavarzi, A.; Klausmeier-Brown, M.E.; Lush, G.B.; Stellwag, T.B. (Purdue Univ., Lafayette, IN (United States))

1993-01-01T23:59:59.000Z

167

Second Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production  

E-Print Network (OSTI)

it as chemical energy. This presents a route for renewable and carbon-neutral fuel production. However, currentSecond Generation Biofuels: High-Efficiency Microalgae for Biodiesel Production Peer M. Schenk that are not only renewable, but also capable of sequestering atmospheric CO2. Currently, nearly all renewable

Kudela, Raphael M.

168

High-quantum efficiency, long-lived luminescing refractory oxides  

DOE Patents (OSTI)

A crystal having a high-quantum efficiency and a long period of luminescence is formed of an oxide selected from the group consisting of magnesium oxide and calcium oxide and possessing a concentration ratio of H.sup.- ions to F centers in the range of about 0.05 to about 10.

Chen, Yok (Oak Ridge, TN); Gonzalez, Roberto (Knoxville, TN); Summers, Geoffrey P. (Stillwater, OK)

1984-01-01T23:59:59.000Z

169

Research on stable, high-efficiency amorphous silicon multijunction modules  

DOE Green Energy (OSTI)

This report describes research to improve the understanding of amorphous silicon alloys and other relevant non-semiconductor materials for use in high-efficiency, large-area multijunction modules. The research produced an average subcell initial efficiency of 8.8% over a 1-ft{sup 2} area using same-band-gap, dual-junction cells deposited over a ZnO/AlSi back reflector. An initial efficiency of 9.6% was achieved using a ZnO/Ag back reflector over smaller substrates. A sputtering machine will be built to deposit a ZnO/Ag back reflector over a 1-ft{sup 2} area so that a higher efficiency can also be obtained on larger substrates. Calculations have been performed to optimize the grid pattern, bus bars, and cell interconnects on modules. With our present state of technology, we expect a difference of about 6% between the aperture-area and active-area efficiencies of modules. Preliminary experiments show a difference of about 8%. We can now predict the performance of single-junction cells after long-term light exposure at 50{degree}C by exposing cells to short-term intense light at different temperatures. We find that single-junction cells deposited on a ZnO/Ag back reflector show the highest stabilized efficiency when the thickness of the intrinsic layers is about 2000 {angstrom}. 8 refs.

Guha, S. (United Solar Systems Corp., Troy, MI (United States))

1991-12-01T23:59:59.000Z

170

Ultra-Compact High-Efficiency Luminaire for General Illumination  

SciTech Connect

Cree has developed a new ultra-compact light emitting diode (LED) luminaire capable of providing high efficacy with excellent color quality that can lead to significant energy savings in todayâ??s commercial and retail applications. This success was based on an integrated development effort tailoring the LED component characteristics, optics, thermal management and driver design for the small footprint to achieve an overall system efficiency of â?¥ 70%. A new LED component was designed to provide high brightness and efficacy in a form factor that allowed for a small directional beam with a luminaire housing design able to dissipate the heat effectively using a small physical envelope. A very compact, 90% efficient driver was developed to meet the system performance while not taking away any thermal mass from the heat sink. A 91% efficient secondary optics was designed to maximize efficiency while providing a smooth beam. The reliability of the new LED component was robust under accelerated testing conditions. Luminaires were assembled integrating the novel LED component, secondary optics, heat sink and driver technology to demonstrate the system improvement. Cree has successfully completed this project by developing an ultra-compact LED luminaire that provided 380 lumens at a correlated color temperature (CCT) of 2822 K and color rendering index (CRI) of 94 with an efficacy of 94 lumens per watt (LPW) when operating at 4 W input power (steady state) with an overall system efficiency of 81%. At a higher input power of 9 Watts, the lamp provided 658 lumens at 71 LPW.

Ted Lowes

2012-04-08T23:59:59.000Z

171

Toward high-energy-density, high-efficiency, and moderate-temperature chip-scale thermophotovoltaics  

E-Print Network (OSTI)

The challenging problem of ultra-high-energy-density, high-efficiency, and small-scale portable power generation is addressed here using a distinctive thermophotovoltaic energy conversion mechanism and chip-based system ...

Pilawa-Podgurski, R. C. N.

172

Energy Efficiency Opportunities in Federal High Performance Computing Data Centers  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Efficiency Efficiency Opportunities in Federal High Performance Computing Data Centers Prepared for the U.S. Department of Energy Federal Energy Management Program By Lawrence Berkeley National Laboratory Rod Mahdavi, P.E. LEED A.P. September 2013 2 Contacts Rod Mahdavi, P.E. LEED AP Lawrence Berkeley National Laboratory (510) 495-2259 rmahdavi@lbl.gov For more information on FEMP: Will Lintner, P.E. Federal Energy Management Program U.S. Department of Energy (202) 586-3120 william.lintner@ee.doe.gov 3 Contents Executive Summary .................................................................................................... 6 Overview .................................................................................................................... 7

173

High-efficiency multidetector system for tumor scanning  

SciTech Connect

A high-efficiency detector system developed especially for medical imaging has three specially cut Ge(Li) coaxial detectors (total volume 249 cm$sup 3$). At 122 keV, the peak efficiency is 93 percent of that of a 7.6 x 7.6 cm NaI (Tl) detector. Degradation of the paralleled energy resolution is avoided and resolution is improved by 35 percent over that of conventional output-summing techniques by gating the detector outputs. In effect this multiplexes them to a single line output. (auth)

Kirby, J.A.; Phelps, P.L.; Armantrout, G.A.; Sawyer, D.; Beck, R.N.

1975-11-18T23:59:59.000Z

174

High Efficiency LED Lamp for Solid-State Lighting  

SciTech Connect

This report contains a summary of technical achievements during a three-year project to demonstrate high efficiency, solid-state lamps based on gallium nitride/silicon carbide light-emitting diodes. Novel chip designs and fabrication processes are described for a new type of nitride light-emitting diode with the potential for very high efficiency. This work resulted in the demonstration of blue light-emitting diodes in the one watt class that achieved up to 495 mW of light output at 350 mA drive current, corresponding to quantum and wall plug efficiencies of 51% and 45%, respectively. When combined with a phosphor in Cree's 7090 XLamp package, these advanced blue-emitting devices resulted in white light-emitting diodes whose efficacy exceeded 85 lumens per watt. In addition, up to 1040 lumens at greater than 85 lumens per watt was achieved by combining multiple devices to make a compact white lamp module with high optical efficiency.

James Ibbetson

2006-12-31T23:59:59.000Z

175

A Perspective on the Future of High Efficiency Engines  

SciTech Connect

New fuel economy standards and emissions regulations are accelerating the development of new engine technologies, sensors, and on-board computing. These developments will enable unprecedented engine control, which will in turn enable real-world implementations of low temperature combustion, high-speed controls, and other high efficiency engine technologies. With this expanded flexibility in engine design and control, the challenge will now be the exponential increase in the design and calibration space and the need for the development of new simulations, optimization methods, and self-learning control methodologies. This manuscript provides historical and future perspectives on the opportunities and challenges of this unparalleled technology growth on the next generation of high efficiency engines.

Wagner, Robert M [ORNL; Curran, Scott [ORNL; Green Jr, Johney Boyd [ORNL

2013-01-01T23:59:59.000Z

176

High Quality Down Lighting Luminaire with 73% Overall System Efficiency  

Science Conference Proceedings (OSTI)

This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.

Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison

2010-08-31T23:59:59.000Z

177

High Quality Down Lighting Luminaire with 73% Overall System Efficiency  

SciTech Connect

This report summarizes work to develop a high flux, high efficiency LED-based downlight at OSRAM SYLVANIA under US Department of Energy contract DE-FC26-08NT01582. A new high power LED and electronic driver were developed for these downlights. The LED achieved 100 lumens per watt efficacy and 1700 lumen flux output at a correlated color temperature of 3500K. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.99, and total harmonic distortion <10%. Two styles of downlights using the LED and driver were shown to exceed the project targets for steady-state luminous efficacy and flux of 70 lumens per watt and 1300 lumens, respectively. Compared to similar existing downlights using compact fluorescent or LED sources, these downlights had much higher efficacy at nearly the same luminous flux.

Robert Harrison; Steven C. Allen; Joseph Bernier; Robert Harrison

2010-08-31T23:59:59.000Z

178

Research on stable, high-efficiency amorphous silicon multijunction modules  

DOE Green Energy (OSTI)

This report describes the progress made during Phase 1 of research and development program to obtain high-efficiency amorphous silicon alloy multijunction modules. Using a large-area deposition system, double-and triple-junction cells were made on stainless steel substrates of over 1 ft{sup 2} area with Ag and ZnO predeposited back reflector. Modules of over 1 ft{sup 2} were produced with between 9.2% and 9.9 initial aperture-area efficiencies as measured under a USSC Spire solar simulator. Efficiencies as measured under the NREL Spire solar simulator were found to be typically 15% to 18% lower. The causes for this discrepancy are now being investigated. The modules show about 15% degradation after 600 hours of one-sun illumination at 50{degrees}C. To optimize devices for higher stabilized efficiency, a new method was developed by which the performance of single-junction cells after long-term, one-sun exposure at 50{degrees}C can be predicted by exposing cells to short-term intense light at different temperatures. This method is being used to optimize the component cells of the multijunction structure to obtain the highest light-degraded efficiency.

Banerjee, A.; Chen, E.; Clough, R.; Glatfelter, T.; Guha, S.; Hammond, G.; Hopson, M.; Jackett, N.; Lycette, M.; Noch, J.; Palmer, T.; Pawlikiewicz, A.; Rosenstein, I.; Ross, R.; Wolf, D.; Xu, X.; Yang, J.; Younan, K.

1992-04-01T23:59:59.000Z

179

High efficiency carbonate fuel cell/turbine hybrid power cycle  

Science Conference Proceedings (OSTI)

The hybrid power cycle studies were conducted to identify a high efficiency, economically competitive system. A hybrid power cycle which generates power at an LHV efficiency > 70% was identified that includes an atmospheric pressure direct carbonate fuel cell, a gas turbine, and a steam cycle. In this cycle, natural gas fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming fuel. The mixed gas then flows to a direct carbonate fuel cell which generates about 70% of the power. The portion of the anode exhaust which is not recycled is burned and heat transferred through a heat exchanger (HX) to the compressed air from a gas turbine. The heated compressed air is then heated further in the gas turbine burner and expands through the turbine generating 15% of the power. Half the exhaust from the turbine provides air for the anode exhaust burner. All of the turbine exhaust eventually flows through the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Exhaust from the cathodes flows to a steam system (heat recovery steam generator, staged steam turbine generating 15% of the cycle power). Simulation of a 200 MW plant with a hybrid power cycle had an LHV efficiency of 72.6%. Power output and efficiency are insensitive to ambient temperature, compared to a gas turbine combined cycle; NOx emissions are 75% lower. Estimated cost of electricity for 200 MW is 46 mills/kWh, which is competitive with combined cycle where fuel cost is > $5.8/MMBTU. Key requirement is HX; in the 200 MW plant studies, a HX operating at 1094 C using high temperature HX technology currently under development by METC for coal gassifiers was assumed. A study of a near term (20 MW) high efficiency direct carbonate fuel cell/turbine hybrid power cycle has also been completed.

Steinfeld, G.; Maru, H.C. [Energy Research Corp., Danbury, CT (United States); Sanderson, R.A. [Sanderson (Robert) and Associates, Wethersfield, CT (United States)

1996-07-01T23:59:59.000Z

180

High-efficiency solar cell and method for fabrication  

DOE Patents (OSTI)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD).

Hou, Hong Q. (Albuquerque, NM); Reinhardt, Kitt C. (Albuquerque, NM)

1999-01-01T23:59:59.000Z

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181

High-efficiency solar cell and method for fabrication  

DOE Patents (OSTI)

A high-efficiency 3- or 4-junction solar cell is disclosed with a theoretical AM0 energy conversion efficiency of about 40%. The solar cell includes p-n junctions formed from indium gallium arsenide nitride (InGaAsN), gallium arsenide (GaAs) and indium gallium aluminum phosphide (InGaAlP) separated by n-p tunnel junctions. An optional germanium (Ge) p-n junction can be formed in the substrate upon which the other p-n junctions are grown. The bandgap energies for each p-n junction are tailored to provide substantially equal short-circuit currents for each p-n junction, thereby eliminating current bottlenecks and improving the overall energy conversion efficiency of the solar cell. Additionally, the use of an InGaAsN p-n junction overcomes super-bandgap energy losses that are present in conventional multi-junction solar cells. A method is also disclosed for fabricating the high-efficiency 3- or 4-junction solar cell by metal-organic chemical vapor deposition (MOCVD). 4 figs.

Hou, H.Q.; Reinhardt, K.C.

1999-08-31T23:59:59.000Z

182

Test Program for High Efficiency Gas Turbine Exhaust Diffuser  

DOE Green Energy (OSTI)

This research relates to improving the efficiency of flow in a turbine exhaust, and thus, that of the turbine and power plant. The Phase I SBIR project demonstrated the technical viability of “strutlets” to control stalls on a model diffuser strut. Strutlets are a novel flow-improving vane concept intended to improve the efficiency of flow in turbine exhausts. Strutlets can help reduce turbine back pressure, and incrementally improve turbine efficiency, increase power, and reduce greenhouse gas emmission. The long-term goal is a 0.5 percent improvement of each item, averaged over the US gas turbine fleet. The strutlets were tested in a physical scale model of a gas turbine exhaust diffuser. The test flow passage is a straight, annular diffuser with three sets of struts. At the end of Phase 1, the ability of strutlets to keep flow attached to struts was demonstrated, but the strutlet drag was too high for a net efficiency advantage. An independently sponsored followup project did develop a highly-modified low-drag strutlet. In combination with other flow improving vanes, complicance to the stated goals was demonstrated for for simple cycle power plants, and to most of the goals for combined cycle power plants using this particular exhaust geometry. Importantly, low frequency diffuser noise was reduced by 5 dB or more, compared to the baseline. Appolicability to other diffuser geometries is yet to be demonstrated.

Norris, Thomas R.

2009-12-31T23:59:59.000Z

183

Integration of High Efficiency Solar Cells on Carriers for Concentrating System Applications .  

E-Print Network (OSTI)

??High efficiency multi-junction (MJ) solar cells were packaged onto receiver systems. The efficiency change of concentrator cells under continuous high intensity illumination was done. Also,… (more)

Chow, Simon Ka Ming

2011-01-01T23:59:59.000Z

184

High Energy-Efficiency Retrofits to Baltimore's Row Homes  

SciTech Connect

The purpose of the research project is to develop high-perfommnce, energy-eflicient retrofits of existing row homes in Baltimore, Maryland. These efficiency enhancements are to optimize building envelope improvements, mechanical equipment improvements and operational improvements to the highest cost-effective level. Furthermore, this project is to investigate and demonstrate the impact of high-performance energy-efficiency retrofit improvements on row homes in the Historic East area of Baltimore. Three homes awaiting renovation are planned to receive building envelope, mechanical system, and electrical system improvements that will improve their energy petiormance. An incremental additional cost ceiling of $4000 for the energy eftlciency improvements, beyond those normally installed, has been set by the project.

Chalk, J.; Johnson, A.L.; Lipscomb, L.; Wendt, R.

1999-04-19T23:59:59.000Z

185

High-Efficiency Solar Cell Concepts: Physics, Materials, and Devices  

DOE Green Energy (OSTI)

Over the past three decades, significant progress has been made in the area of high-efficiency multijunction solar cells, with the effort primarily directed at current-matched solar cells in tandem. The key materials issues here have been obtaining semiconductors with the required bandgaps for sequential absorption of light in the solar spectrum and that are lattice matched to readily available substrates. The GaInP/GaAs/Ge cell is a striking example of success achieved in this area. Recently, several new approaches for high-efficiency solar cell design have emerged, that involve novel methods for tailoring alloy bandgaps, as well as alternate technologies for hetero-epitaxy of III-V's on Si. The advantages and difficulties expected to be encountered with each approach will be discussed, addressing both the materials issues and device physics whilst contrasting them with other fourth-generation solar cell concepts.

Mascarenhas, A.; Francoeur, S.; Seong, M. J.; Fluegel, B.; Zhang, Y.; Wanlass, M. W.

2005-01-01T23:59:59.000Z

186

Modelling and fabrication of high-efficiency silicon solar cells  

DOE Green Energy (OSTI)

This report covers the research conducted on modelling and development of high-efficiency silicon solar cells during the period May 1989 to August 1990. First, considerable effort was devoted toward developing a ray-tracing program for the photovoltaic community to quantify and optimize surface texturing for solar cells. Second, attempts were made to develop a hydrodynamic model for device simulation. Such a model is somewhat slower than drift-diffusion type models like PC-1D, but it can account for more physical phenomena in the device, such as hot carrier effects, temperature gradients, thermal diffusion, and lattice heat flow. In addition, Fermi-Dirac statistics have been incorporated into the model to deal with heavy doping effects more accurately. Third and final component of the research includes development of silicon cell fabrication capabilities and fabrication of high-efficiency silicon cells. 84 refs., 46 figs., 10 tabs.

Rohatgi, A.; Smith, A.W.; Salami, J. [Georgia Inst. of Tech., Atlanta, GA (United States). School of Electrical Engineering] [Georgia Inst. of Tech., Atlanta, GA (United States). School of Electrical Engineering

1991-10-01T23:59:59.000Z

187

Fuel Cell/Turbine Ultra High Efficiency Power System  

DOE Green Energy (OSTI)

FuelCell Energy, INC. (FCE) is currently involved in the design of ultra high efficiency power plants under a cooperative agreement (DE-FC26-00NT40) managed by the National Energy Technology Laboratory (NETL) as part of the DOE's Vision 21 program. Under this project, FCE is developing a fuel cell/turbine hybrid system that integrates the atmospheric pressure Direct FuelCell{reg_sign} (DFC{reg_sign}) with an unfired Brayton cycle utilizing indirect heat recovery from the power plant. Features of the DFC/T{trademark} system include: high efficiency, minimal emissions, simplicity in design, direct reforming internal to the fuel cell, no pressurization of the fuel cell, independent operating pressure of the fuel cell and turbine, and potential cost competitiveness with existing combined cycle power plants at much smaller sizes. Objectives of the Vision 21 Program include developing power plants that will generate electricity with net efficiencies approaching 75 percent (with natural gas), while producing sulfur and nitrogen oxide emissions of less than 0.01 lb/million BTU. These goals are significant improvements over conventional power plants, which are 35-60 percent efficient and produce emissions of 0.07 to 0.3 lb/million BTU of sulfur and nitrogen oxides. The nitrogen oxide and sulfur emissions from the DFC/T system are anticipated to be better than the Vision 21 goals due to the non-combustion features of the DFC/T power plant. The expected high efficiency of the DFC/T will also result in a 40-50 percent reduction in carbon dioxide emissions compared to conventional power plants. To date, the R&D efforts have resulted in significant progress including proof-of-concept tests of a sub-scale power plant built around a state-of-the-art DFC stack integrated with a modified Capstone Model 330 Microturbine. The objectives of this effort are to investigate the integration aspects of the fuel cell and turbine and to obtain design information and operational data that will be utilized in the design of a 40-MW high efficiency Vision 21 power plant. Additionally, these tests are providing the valuable insight for DFC/Turbine power plant potential for load following, increased reliability, and enhanced operability.

Hossein, Ghezel-Ayagh

2001-11-06T23:59:59.000Z

188

Photo-oxidation catalysts  

DOE Patents (OSTI)

Photo-oxidation catalysts and methods for cleaning a metal-based catalyst are disclosed. An exemplary catalyst system implementing a photo-oxidation catalyst may comprise a metal-based catalyst, and a photo-oxidation catalyst for cleaning the metal-based catalyst in the presence of light. The exposure to light enables the photo-oxidation catalyst to substantially oxidize absorbed contaminants and reduce accumulation of the contaminants on the metal-based catalyst. Applications are also disclosed.

Pitts, J. Roland (Lakewood, CO); Liu, Ping (Irvine, CA); Smith, R. Davis (Golden, CO)

2009-07-14T23:59:59.000Z

189

Symmetric quantum dots as efficient sources of highly entangled photons  

E-Print Network (OSTI)

An ideal source of entangled photon pairs combines the perfect symmetry of an atom with the convenient electrical trigger of light sources based on semiconductor quantum dots. We create a naturally symmetric quantum dot cascade that emits highly entangled photon pairs on demand. Our source consists of strain-free GaAs dots self-assembled on a triangular symmetric (111)A surface. The emitted photons strongly violate Bell's inequality and reveal a fidelity to the Bell state as high as 86 (+-2) % without postselection. This result is an important step towards scalable quantum-communication applications with efficient sources.

T. Kuroda; T. Mano; N. Ha; H. Nakajima; H. Kumano; B. Urbaszek; M. Jo; M. Abbarachi; Y. Sakuma; K. Sakoda; I. Suemune; X. Marie; T. Amand

2013-02-26T23:59:59.000Z

190

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER  

DOE Green Energy (OSTI)

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could benefit, in terms of efficien

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01T23:59:59.000Z

191

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER  

SciTech Connect

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from fossil fuels has trace contaminants (primarily carbon monoxide) that are detrimental to precious metal catalyzed fuel cells, as is now recognized by many of the world's largest automobile companies. Thermochemical hydrogen will not contain carbon monoxide as an impurity at any level. Electrolysis, the alternative process for producing hydrogen using nuclear energy, suffers from thermodynamic inefficiencies in both the production of electricity and in electrolytic parts of the process. The efficiency of electrolysis (electricity to hydrogen) is currently about 80%. Electric power generation efficiency would have to exceed 65% (thermal to electrical) for the combined efficiency to exceed the 52% (thermal to hydrogen) calculated for one thermochemical cycle. Thermochemical water-splitting cycles have been studied, at various levels of effort, for the past 35 years. They were extensively studied in the late 70s and early 80s but have received little attention in the past 10 years, particularly in the U.S. While there is no question about the technical feasibility and the potential for high efficiency, cycles with proven low cost and high efficiency have yet to be developed commercially. Over 100 cycles have been proposed, but substantial research has been executed on only a few. This report describes work accomplished during a three-year project whose objective is to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high temperature nuclear reactor as the energy source.'' The emphasis of the first phase was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen from water in which the primary energy input is high temperature heat from an advanced nuclear reactor and to select one (or, at most three) for further detailed consideration. During Phase 1, an exhaustive literature search was performed to locate all cycles previously proposed. The cycles located were screened using objective criteria to determine which could

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01T23:59:59.000Z

192

In-Plant Testing of High-Efficiency Hydraulic Separators  

SciTech Connect

Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. These units, which are commercially called the CrossFlow separator and HydroFloat separator, have the potential to improve performance (separation efficiency and throughput) and reduce operating costs (power consumption, water and reagent usage). In Phase I of this project, laboratory and pilot-scale test units were evaluated at various industrial sites in both the coal and mineral industries. Based on promising results obtained from Phase I, full-scale prototypes were purchased and installed by a major U.S. phosphate producer and a large eastern U.S. coal company. The test data obtained from these sites demonstrate that significant performance improvements can be realized through the application of these high-efficiency separators.

G. H. Luttrell; R. Q. Honaker; R. C. Bratton; T. C. Westerfield; J. N. Kohmuench

2006-06-30T23:59:59.000Z

193

IN-PLANT TESTING OF HIGH-EFFICIENCY HYDRAULIC SEPARATORS  

SciTech Connect

Hydraulic separators are commonly used for particle size classification and gravity concentration of minerals and coal. Unfortunately, the efficiency of these processes can be quite low due to poor equipment design and variations in feed consistency. To help alleviate these problems, an industry-driven R&D program has been undertaken to develop a new generation of hydraulic separators that are more efficient and less costly to operate and maintain. These units, which are commercially called the CrossFlow separator and HydroFloat separator, have the potential to improve performance (separation efficiency and throughput) and reduce operating costs (power consumption, water and reagent usage). In Phase I of this project, laboratory and pilot-scale test units were evaluated at various industrial sites in both the coal and mineral industries. Based on promising results obtained from Phase I, full-scale prototypes were purchased and installed by a major U.S. phosphate producer and a large eastern U.S. coal company. The test data obtained from these sites demonstrate that significant performance improvements can be realized through the application of these high-efficiency separators.

G.H. Luttrell; R.Q. Honaker; R.C. Bratton; T.C. Westerfield; J.N. Kohmuench

2006-05-22T23:59:59.000Z

194

Materials - Catalysts for Diesel Engines  

NLE Websites -- All DOE Office Websites (Extended Search)

Argonne's deNOx Catalyst Begins Extensive Diesel Engine Exhaust Testing Argonne's deNOx Catalyst Begins Extensive Diesel Engine Exhaust Testing denox monolith Argonne's deNOx catalyst can be prepared as a powder or a monolith. chris marshall Principal investigator Chris Marshall shows the monolith form of the Argonne deNOx catalyst with a sensor inserted for testing. doug longman Mechanical engineer Doug Longman inserts the instrumented deNOx catalyst monolith into the aftertreatment chamber of Argonne's heavy-duty Caterpillar diesel test engine. Background Diesel engines, while efficient, produce many undesirable combustion byproducts in their exhaust. While we tend to think of the sooty exhaust products we see as the bad stuff, it is the less-visible exhaust products such as nitrogen oxides (NOx) that create bigger problems.

195

System Effects of High Efficiency Filters in Homes  

NLE Websites -- All DOE Office Websites (Extended Search)

System Effects of High Efficiency Filters in Homes System Effects of High Efficiency Filters in Homes Title System Effects of High Efficiency Filters in Homes Publication Type Conference Paper LBNL Report Number LBNL-6144E Year of Publication 2013 Authors Walker, Iain S., Darryl J. Dickerhoff, David Faulkner, and William J. N. Turner Conference Name ASHRAE Annual Conference Date Published 03/2013 Abstract Occupant concern about indoor air quality (IAQ) issues has led to the increased use of more effective air filters in residential heating and cooling systems. A drawback of improved filtration is that better filters tend to have more flow resistance. This can lead to lower system airflows that reduce heat exchanger efficiency, increase duct pressure that leads to increased air leakage for ducts and, in some case s, increased blower power consumption. There is currently little knowledge on the magnitude of these effects. In this study, the performance of ten central forced air systems was monitored for a year. The systems used either a Permanent Split Capacitor (PSC) or a Brushless Permanent Magnet (BPM) blower. Each system was operated with a range of filter efficiencies ranging from MERV 6 (the lowest currently permitted in ASHRAE Standard 62.2) up to MERV 16. Measurements were recorded every ten seconds for blower power, filter pressure drop, supply and return plenum pressures together with plenum and indoor temperatures. These detailed continuous measurements allowed observation of filter loading effects as well as the initial change in system performance when filters were swapped. The results of the field measurements were used in simulations to examine more general system performance effects for a wider range of climates. The field tests showed that system static pressures were highly influenced by filter selection, filter loading rates varied more from house to house than by MERV rating and overall were quite low in many of the homes. PSC motors showed reduced power and airflow as the filters loaded, but BPM motors attempted to maintain a constant airflow and increased their power to do so. The combined field test and simulation results from this study indicate that for MERV 10-13 filters the effects on energy use are small (5%) and usability. In systems using low MERV filters that are already close to blower performance limits the addition of a MERV 16 filter pushed the blowers to their performance limits.

196

Design of high efficiency blowers for future aerosol applications  

E-Print Network (OSTI)

High efficiency air blowers to meet future portable aerosol sampling applications were designed, fabricated, and evaluated. A Centrifugal blower was designed to achieve a flow rate of 100 L/min (1.67 x 10^-3 m^3/s) and a pressure rise of WC " 4 (1000 PA). Commercial computational fluid dynamics (CFD) software, FLUENT 6.1.22, was used extensively throughout the entire design cycle. The machine, Reynolds number (Re) , was around 10^5 suggesting a turbulent flow field. Renormalization Group (RNG) �ºâ���µ turbulent model was used for FLUENT simulations. An existing design was scaled down to meet the design needs. Characteristic curves showing static pressure rise as a function of flow rate through the impeller were generated using FLUENT and these were validated through experiments. Experimentally measured efficiency (�·EXP) for the base-design was around 10%. This was attributed to the low efficiency of the D.C. motor used. CFD simulations, using the �ºâ���µ turbulent model and standard wall function approach, over-predicted the pressure rise values and the percentage error was large. Enhanced wall function under-predicted the pressure rise but gave better agreement (less than 6% error) with experimental results. CFD predicted a blower scaled 70% in planar direction (XZ) and 28% in axial direction (Y) and running at 19200 rpm (70xz_28y@19.2k) as the most appropriate choice. The pressure rise is 1021 Pa at the design flow rate of 100 L/min. FLUENT predicts an efficiency value based on static head (�·FLU) as 53.3%. Efficiency value based on measured static pressure rise value and the electrical energy input to the motor (�·EXP) is 27.4%. This is almost a 2X improvement over the value that one gets with the hand held vacuum system blower.

Chadha, Raman

2005-12-01T23:59:59.000Z

197

HIGH EFFICIENCY FOSSIL POWER PLANT (HEFPP) CONCEPTUALIZATION PROGRAM  

SciTech Connect

This study confirms the feasibility of a natural gas fueled, 20 MW M-C Power integrated pressurized molten carbonate fuel cell combined in a topping cycle with a gas turbine generator plant. The high efficiency fossil power plant (HEFPP) concept has a 70% efficiency on a LHV basis. The study confirms the HEFPP has a cost advantage on a cost of electricity basis over the gas turbine based combined cycle plants in the 20 MW size range. The study also identifies the areas of further development required for the fuel cell, gas turbine generator, cathode blower, inverter, and power module vessel. The HEFPP concept offers an environmentally friendly power plant with minuscule emission levels when compared with the combined cycle power plant.

J.L. Justice

1999-03-25T23:59:59.000Z

198

Implications of high efficiency power cycles for fusion reactor design  

SciTech Connect

The implications of the High Efficiency Power Cycle for fusion reactors are examined. The proposed cycle converts most all of the high grade CTR heat input to electricity. A low grade thermal input (T approximately 100$sup 0$C) is also required, and this can be supplied at low cost geothermal energy at many locations in the U. S. Approximately 3 KW of low grade heat is required per KW of electrical output. The thermodynamics and process features of the proposed cycle are discussed. Its advantages for CTR's are that low Q machines (e.g. driven Tokamaks, mirrors) can operate with a high (approximately 80 percent) conversion of CTR fusion energy to electricity, where with conventional power cycles no plant output could be achieved with such low Q operation. (auth)

Powell, J.R.; Usher, J.; Salzano, F.J.

1975-01-01T23:59:59.000Z

199

Accelerated deployment of nanostructured hydrotreating catalysts. Final CRADA Report.  

Science Conference Proceedings (OSTI)

Nanomanufacturing offers an opportunity to create domestic jobs and facilitate economic growth. In response to this need, U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy issued a Research Call to develop nanomanufacturing capabilities at the National Laboratories. High performance catalysts represent a unique opportunity to deploy nanomanufacturing technologies. Re-refining of used lube oil offers an opportunity to create manufacturing jobs and decrease dependence on imported petroleum. Improved catalysts are required to produce a better quality product, decrease environmental impact, extend catalyst life, and improve overall economics of lube oil re-refining. Argonne National Laboratory (Argonne) in cooperation with Universal Lubricants, Inc. (ULI) and Chemical Engineering Partners (CEP) have carried out a Cooperative Research and Development Agreement (CRADA) to prepare nanostructured hydrotreating catalysts using atomic layer deposition (ALD) to exhibit superior performance for the re-refining of used lube oil. We investigated the upgrading of recycled lube oil by hydrogenation using commercial, synthetically-modified commercial catalysts, and synthesized catalysts. A down-flow (trickle bed) catalytic unit was used for the hydrogenation experiments. In addition to carrying out elemental analyses of the various feed and product fractions, characterization was undertaken using H{sup 1} and C{sup 13} NMR. Initially commercial were evaluated. Second these commercial catalysts were promoted with precious metals using atomic layer deposition (ALD). Performance improvements were observed that declined with catalyst aging. An alternate approach was undertaken to deeply upgrade ULI product oils. Using a synthesized catalyst, much lower hydrogenation temperatures were required than commercial catalysts. Other performance improvements were also observed. The resulting lube oil fractions were of high purity even at low reaction severity. The products recovered from both the ALD and other processes were water-white (even those from the low temperature, low residence time (high space velocity), low conversion runs). These results indicate that highly upgraded recycle lube oils can be produced using ALD-deposited active metal catalysts. The use of H{sup 1} and C{sup 13} NMR for the characterization of the treated lube oils has been shown to be effective.

Libera, J.A.; Snyder, S.W.; Mane, A.; Elam, J.W.; Cronauer, D.C.; Muntean, J.A.; Wu, T.; Miller, J.T. (Chemical Sciences and Engineering Division); ( ES)

2012-08-27T23:59:59.000Z

200

Modeling Species Inhibition and Competitive Adsorption in Urea-SCR Catalysts  

Science Conference Proceedings (OSTI)

Although the urea-SCR technology exhibits high NOx reduction efficiency over a wide range of temperatures among the lean NOx reduction technologies, further improvement in low-temperature performance is required to meet the future emission standards and to lower the system cost. In order to improve the catalyst technologies and optimize the system performance, it is critical to understand the reaction mechanisms and catalyst behaviors with respect to operating conditions. Urea-SCR catalysts exhibit poor NOx reduction performance at low temperature operating conditions (T catalysts based on bench reactor experiments. We further use the competitive adsorption (CA) model to develop a standard SCR model based on previously identified kinetics. Simulation results indicate that the CA model predicts catalyst outlet NO and NH3 concentrations with minimal root mean square error.

Devarakonda, Maruthi N.; Tonkyn, Russell G.; Lee, Jong H.

2012-04-16T23:59:59.000Z

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201

Mixed Alcohol Synthesis Catalyst Screening  

DOE Green Energy (OSTI)

National Renewable Energy Laboratory (NREL) and Pacific Northwest National Laboratory (PNNL) are conducting research to investigate the feasibility of producing mixed alcohols from biomass-derived synthesis gas (syngas). PNNL is tasked with obtaining commercially available or preparing promising mixed-alcohol catalysts and screening them in a laboratory-scale reactor system. Commercially available catalysts and the most promising experimental catalysts are provided to NREL for testing using a slipstream from a pilot-scale biomass gasifier. From the standpoint of producing C2+ alcohols as the major product, it appears that the rhodium catalyst is the best choice in terms of both selectivity and space-time yield (STY). However, unless the rhodium catalyst can be improved to provide minimally acceptable STYs for commercial operation, mixed alcohol synthesis will involve significant production of other liquid coproducts. The modified Fischer-Tropsch catalyst shows the most promise for providing both an acceptable selectivity to C2+ alcohols and total liquid STY. However, further optimization of the Fischer-Tropsch catalysts to improve selectivity to higher alcohols is highly desired. Selection of a preferred catalyst will likely entail a decision on the preferred coproduct slate. No other catalysts tested appear amenable to the significant improvements needed for acceptable STYs.

Gerber, Mark A.; White, James F.; Stevens, Don J.

2007-09-03T23:59:59.000Z

202

A High Efficiency PSOFC/ATS-Gas Turbine Power System  

DOE Green Energy (OSTI)

A study is described in which the conceptual design of a hybrid power system integrating a pressurized Siemens Westinghouse solid oxide fuel cell generator and the Mercury{trademark} 50 gas turbine was developed. The Mercury{trademark} 50 was designed by Solar Turbines as part of the US. Department of Energy Advanced Turbine Systems program. The focus of the study was to develop the hybrid power system concept that principally would exhibit an attractively-low cost of electricity (COE). The inherently-high efficiency of the hybrid cycle contributes directly to achieving this objective, and by employing the efficient, power-intensive Mercury{trademark} 50, with its relatively-low installed cost, the higher-cost SOFC generator can be optimally sized such that the minimum-COE objective is achieved. The system cycle is described, major system components are specified, the system installed cost and COE are estimated, and the physical arrangement of the major system components is discussed. Estimates of system power output, efficiency, and emissions at the system design point are also presented. In addition, two bottoming cycle options are described, and estimates of their effects on overall-system performance, cost, and COE are provided.

W.L. Lundberg; G.A. Israelson; M.D. Moeckel; S.E. Veyo; R.A. Holmes; P.R. Zafred; J.E. King; R.E. Kothmann

2001-02-01T23:59:59.000Z

203

Analysis of highly-efficient electric residential HPWHs  

DOE Green Energy (OSTI)

A scoping level analysis was conducted to identify electric HPWH concepts that have the potential to achieve or exceed 30% source energy savings compared to a gas tankless water heater (GTWH) representative of the type represented in version 0.9.5.2 beta of the BEopt software developed by the National Renewable Energy Laboratory. The analysis was limited to evaluation of options to improve the energy efficiency of electric HPWH product designs currently on the market in the US. The report first defines the baseline GTWH system and determines its efficiency (source-energy-based adjusted or derated EF of ~0.71). High efficiency components (compressors, pumps, fans, heat exchangers, etc.) were identified and applied to current US HPWH products and analyzed to determine the viability of reaching the target EF. The target site-based energy factor (EF) required for an electric HPWH necessary to provide 30% source energy savings compared to the GTWH baseline unit is then determined to be ~3.19.

Baxter, Van D [ORNL; Murphy, Richard W [ORNL; Rice, C Keith [ORNL; Shen, Bo [ORNL; Gao, Zhiming [ORNL

2011-09-01T23:59:59.000Z

204

Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas  

SciTech Connect

Observations of improved radio frequency (RF) heating efficiency in high-confinement (H-) mode plasmas on the National Spherical Tokamak Experiment (NSTX) are investigated by whole-device linear simulation. We present the first full-wave simulation to couple kinetic physics of the well confined core plasma to the poorly confined scrape-off plasma. The new simulation is used to scan the launched fast-wave spectrum and examine the steady-state electric wave field structure for experimental scenarios corresponding to both reduced, and improved RF heating efficiency. We find that launching toroidal wave-numbers that required for fast-wave propagation excites large amplitude (kVm 1 ) coaxial standing modes in the wave electric field between the confined plasma density pedestal and conducting vessel wall. Qualitative comparison with measurements of the stored plasma energy suggest these modes are a probable cause of degraded heating efficiency. Also, the H-mode density pedestal and fast-wave cutoff within the confined plasma allow for the excitation of whispering gallery type eigenmodes localised to the plasma edge.

Green, David L [ORNL; Jaeger, E. F. [XCEL; Berry, Lee A [ORNL; Chen, Guangye [ORNL; Ryan, Philip Michael [ORNL; Canik, John [ORNL

2011-01-01T23:59:59.000Z

205

Nano Catalysts for Diesel Engine Emission Remediation  

DOE Green Energy (OSTI)

The objective of this project was to develop durable zeolite nanocatalysts with broader operating temperature windows to treat diesel engine emissions to enable diesel engine based equipment and vehicles to meet future regulatory requirements. A second objective was to improve hydrothermal durability of zeolite catalysts to at least 675 C. The results presented in this report show that we have successfully achieved both objectives. Since it is accepted that the first step in NO{sub x} conversion under SCR (selective catalytic reduction) conditions involves NO oxidation to NO{sub 2}, we reasoned that catalyst modification that can enhance NO oxidation at low-temperatures should facilitate NO{sub x} reduction at low temperatures. Considering that Cu-ZSM-5 is a more efficient catalyst than Fe-ZSM-5 at low-temperature, we chose to modify Cu-ZSM-5. It is important to point out that the poor low-temperature efficiency of Fe-ZSM-5 has been shown to be due to selective absorption of NH{sub 3} at low-temperatures rather than poor NO oxidation activity. In view of this, we also reasoned that an increased electron density on copper in Cu-ZSM-5 would inhibit any bonding with NH{sub 3} at low-temperatures. In addition to modified Cu-ZSM-5, we synthesized a series of new heterobimetallic zeolites, by incorporating a secondary metal cation M (Sc{sup 3+}, Fe{sup 3+}, In{sup 3+}, and La{sup 3+}) in Cu exchanged ZSM-5, zeolite-beta, and SSZ-13 zeolites under carefully controlled experimental conditions. Characterization by diffuse-reflectance ultra-violet-visible spectroscopy (UV-Vis), X-ray powder diffraction (XRD), extended X-ray absorption fine structure spectroscopy (EXAFS) and electron paramagnetic resonance spectroscopy (EPR) does not permit conclusive structural determination but supports the proposal that M{sup 3+} has been incorporated in the vicinity of Cu(II). The protocols for degreening catalysts, testing under various operating conditions, and accelerated aging conditions were provided by our collaborators at John Deere Power Systems. Among various zeolites reported here, CuFe-SSZ-13 offers the best NO{sub x} conversion activity in 150-650 C range and is hydrothermally stable when tested under accelerated aging conditions. It is important to note that Cu-SSZ-13 is now a commercial catalyst for NO{sub x} treatment on diesel passenger vehicles. Thus, our catalyst performs better than the commercial catalyst under fast SCR conditions. We initially focused on fast SCR tests to enable us to screen catalysts rapidly. Only the catalysts that exhibit high NO{sub x} conversion at low temperatures are selected for screening under varying NO{sub 2}:NO{sub x} ratio. The detailed tests of CuFe-SSZ-13 show that CuFe-SSZ-13 is more effective than commercial Cu-SSZ-13 even at NO{sub 2}:NO{sub x} ratio of 0.1. The mechanistic studies, employing stop-flow diffuse reflectance FTIR spectroscopy (DRIFTS), suggest that high concentration of NO{sup +}, generated by heterobimetallic zeolites, is probably responsible for their superior low temperature NO{sub x} activity. The results described in this report clearly show that we have successfully completed the first step in a new emission treatment catalyst which is synthesis and laboratory testing employing simulated exhaust. The next step in the catalyst development is engine testing. Efforts are in progress to obtain follow-on funding to carry out scale-up and engine testing to facilitate commercialization of this technology.

Narula, Chaitanya Kumar [ORNL; Yang, Xiaofan [ORNL; Debusk, Melanie Moses [ORNL; Mullins, David R [ORNL; Mahurin, Shannon Mark [ORNL; Wu, Zili [ORNL

2012-06-01T23:59:59.000Z

206

Thin Film Packaging Solutions for High Efficiency OLED Lighting Products  

Science Conference Proceedings (OSTI)

The objective of the 'Thin Film Packaging Solutions for High Efficiency OLED Lighting Products' project is to demonstrate thin film packaging solutions based on SiC hermetic coatings that, when applied to glass and plastic substrates, support OLED lighting devices by providing longer life with greater efficiency at lower cost than is currently available. Phase I Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on optical glass with lifetime of 1,000 hour life, CRI greater than 75, and 15 lm/W. Phase II Objective: Demonstrate thin film encapsulated working phosphorescent OLED devices on plastic or glass composite with 25 lm/W, 5,000 hours life, and CRI greater than 80. Phase III Objective: Demonstrate 2 x 2 ft{sup 2} thin film encapsulated working phosphorescent OLED with 40 lm/W, 10,000 hour life, and CRI greater than 85. This report details the efforts of Phase III (Budget Period Three), a fourteen month collaborative effort that focused on optimization of high-efficiency phosphorescent OLED devices and thin-film encapsulation of said devices. The report further details the conclusions and recommendations of the project team that have foundation in all three budget periods for the program. During the conduct of the Thin Film Packaging Solutions for High Efficiency OLED Lighting Products program, including budget period three, the project team completed and delivered the following achievements: (1) a three-year marketing effort that characterized the near-term and longer-term OLED market, identified customer and consumer lighting needs, and suggested prototype product concepts and niche OLED applications lighting that will give rise to broader market acceptance as a source for wide area illumination and energy conservation; (2) a thin film encapsulation technology with a lifetime of nearly 15,000 hours, tested by calcium coupons, while stored at 16 C and 40% relative humidity ('RH'). This encapsulation technology was characterized as having less than 10% change in transmission during the 15,000 hour test period; (3) demonstrated thin film encapsulation of a phosphorescent OLED device with 1,500 hours of lifetime at 60 C and 80% RH; (4) demonstrated that a thin film laminate encapsulation, in addition to the direct thin film deposition process, of a polymer OLED device was another feasible packaging strategy for OLED lighting. The thin film laminate strategy was developed to mitigate defects, demonstrate roll-to-roll process capability for high volume throughput (reduce costs) and to support a potential commercial pathway that is less dependent upon integrated manufacturing since the laminate could be sold as a rolled good; (5) demonstrated that low cost 'blue' glass substrates could be coated with a siloxane barrier layer for planarization and ion-protection and used in the fabrication of a polymer OLED lighting device. This study further demonstrated that the substrate cost has potential for huge cost reductions from the white borosilicate glass substrate currently used by the OLED lighting industry; (6) delivered four-square feet of white phosphorescent OLED technology, including novel high efficiency devices with 82 CRI, greater than 50 lm/W efficiency, and more than 1,000 hours lifetime in a product concept model shelf; (7) presented and or published more than twenty internal studies (for private use), three external presentations (OLED workshop-for public use), and five technology-related external presentations (industry conferences-for public use); and (8) issued five patent applications, which are in various maturity stages at time of publication. Delivery of thin film encapsulated white phosphorescent OLED lighting technology remains a challenging technical achievement, and it seems that commercial availability of thin, bright, white OLED light that meets market requirements will continue to require research and development effort. However, there will be glass encapsulated white OLED lighting products commercialized in niche markets during the 2008 calendar year. This commercializ

None

2008-06-30T23:59:59.000Z

207

Method Development to Evaluate the Oxygen Reduction Activity of High-Surface-Area Catalysts for Li-Air Batteries  

E-Print Network (OSTI)

This study presents a new method to quantitatively determine the electrocatalytic activity of Vulcan carbon and Vulcan-supported Au nanoparticles, dispersed as catalyst thin films on glass carbon, for oxygen reduction in ...

Lu, Yi-Chun

208

HIGH EFFICIENCY BIFACIAL BACK SURFACE FIELD SOLAR CELLS  

E-Print Network (OSTI)

The first high efficiency p÷-n-n + bifacial solar cells are presented. Efficiencies of 15.7 % and 13.6 % were measured under front and back air mass one illumination respectively at 28 °C. At 7 air mass one illumination and 28 °C the front efficiency increases to 16.5%. A pilot production of 200 cells was made following a fabrication process as simple as that for conventional back surface field cells. Mean efficiencies of 13.4 % and 10.7 % were obtained under front and back illumination respectively. The production yield is higher than 80%. The advantages that bifacial cells present in some applications, compared with conventional cells, have been pointed out for static [1] and quasi-static [2] concentrating systems, for luminescent concentrators [3] and also for flat panels. A transistor-like structure (n+-p-n +) has already been developed as a bifacial cell [4]. We have also suggested [5] and theoretically analysed [6] the use of a back surface field (BSF) structure (n+-p-p ÷ or p+-n-n +) as a bifacial cell. The purpose here is to demonstrate the feasibility of high efficiency bifacial BSF solar cells. p+-n-n ÷ bifacial cells with a 5 cm 2 area were made on float-zone silicon wafers. The resistivity of the n-type base region was 10 ~2 cm and the thickness was 260 pm. The p ÷ and n + regions were formed by open-tube diffusions using BBr3 and POC13 sources, the resulting sheet resistance being 45- 60 ~2/[:] for the p ÷ layer and 20- 30 ~2/[:] for the n ÷ layer. A TiOx antireflection (AR) coating was spun onto both sides of the cell; Ti-Pd-Ag grids were sputtered and lift-off defined also on both faces. The metallization pattern was designed for the cells to operate inside static compound parabolic mirrors with a concentration factor of 5 and a non-uniform distribution of light intensity on the cell surface. The optimum grid has ten fingers per centimetre (each finger is 50- 70 pm wide) and produces a coverage factor in the illuminated area of about 5.5%.

A. Cuevas; A. Luque; J. Eguren; J. Del Alamo

1980-01-01T23:59:59.000Z

209

High-Efficiency Nitride-Base Photonic Crystal Light Sources  

DOE Green Energy (OSTI)

The research activities performed in the framework of this project represent a major breakthrough in the demonstration of Photonic Crystals (PhC) as a competitive technology for LEDs with high light extraction efficiency. The goals of the project were to explore the viable approaches to manufacturability of PhC LEDS through proven standard industrial processes, establish the limits of light extraction by various concepts of PhC LEDs, and determine the possible advantages of PhC LEDs over current and forthcoming LED extraction concepts. We have developed three very different geometries for PhC light extraction in LEDs. In addition, we have demonstrated reliable methods for their in-depth analysis allowing the extraction of important parameters such as light extraction efficiency, modal extraction length, directionality, internal and external quantum efficiency. The information gained allows better understanding of the physical processes and the effect of the design parameters on the light directionality and extraction efficiency. As a result, we produced LEDs with controllable emission directionality and a state of the art extraction efficiency that goes up to 94%. Those devices are based on embedded air-gap PhC - a novel technology concept developed in the framework of this project. They rely on a simple and planar fabrication process that is very interesting for industrial implementation due to its robustness and scalability. In fact, besides the additional patterning and regrowth steps, the process is identical as that for standard industrially used p-side-up LEDs. The final devices exhibit the same good electrical characteristics and high process yield as a series of test standard LEDs obtained in comparable conditions. Finally, the technology of embedded air-gap patterns (PhC) has significant potential in other related fields such as: increasing the optical mode interaction with the active region in semiconductor lasers; increasing the coupling of the incident light into the active region of solar cells; increasing the efficiency of the phosphorous light conversion in white light LEDs etc. In addition to the technology of embedded PhC LEDs, we demonstrate a technique for improvement of the light extraction and emission directionality for existing flip-chip microcavity (thin) LEDs by introducing PhC grating into the top n-contact. Although, the performances of these devices in terms of increase of the extraction efficiency are not significantly superior compared to those obtained by other techniques like surface roughening, the use of PhC offers some significant advantages such as improved and controllable emission directionality and a process that is directly applicable to any material system. The PhC microcavity LEDs have also potential for industrial implementation as the fabrication process has only minor differences to that already used for flip-chip thin LEDs. Finally, we have demonstrated that achieving good electrical properties and high fabrication yield for these devices is straightforward.

James Speck; Evelyn Hu; Claude Weisbuch; Yong-Seok Choi; Kelly McGroddy; Gregor Koblmuller; Elison Matioli; Elizabeth Rangel; Fabian Rol; Dobri Simeonov

2010-01-31T23:59:59.000Z

210

High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency  

E-Print Network (OSTI)

Roadmap to Improved Energy Efficiency iii 11-Sept-2009 ListA Roadmap to Improved Energy Efficiency 11-Sept-2009 Topic /A Roadmap to Improved Energy Efficiency 11-Sept-2009 Topic /

Singer, Brett C.

2010-01-01T23:59:59.000Z

211

Method for generating a highly reactive plasma for exhaust gas aftertreatment and enhanced catalyst reactivity  

DOE Patents (OSTI)

A method for non-thermal plasma aftertreatment of exhaust gases the method comprising the steps of providing short risetime (about 40 ps), high frequency (about 5G hz), high power bursts of low-duty factor microwaves sufficient to generate a dielectric barrier discharge and passing a gas to treated through the discharge so as to cause dissociative reduction of the exhaust gases. The invention also includes a reactor for generating the non-thermal plasma.

Whealton, John H. (Oak Ridge, TN); Hanson, Gregory R. (Clinton, TN); Storey, John M. (Oak Ridge, TN); Raridon, Richard J. (Oak Ridge, TN); Armfield, Jeffrey S. (Upsilanti, MI); Bigelow, Timothy S. (Knoxville, TN); Graves, Ronald L. (Knoxville, TN)

2001-01-01T23:59:59.000Z

212

Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems  

Science Conference Proceedings (OSTI)

Industrial manufacturing in the U.S. accounts for roughly one third of the 98 quadrillion Btu total energy consumption. Motor system losses amount to 1.3 quadrillion Btu, which represents the largest proportional loss of any end-use category, while pumps alone represent over 574 trillion BTU (TBTU) of energy loss each year. The efficiency of machines with moving components is a function of the amount of energy lost to heat because of friction between contacting surfaces. The friction between these interfaces also contributes to downtime and the loss of productivity through component wear and subsequent repair. The production of new replacement parts requires additional energy. Among efforts to reduce energy losses, wear-resistant, low-friction coatings on rotating and sliding components offer a promising approach that is fully compatible with existing equipment and processes. In addition to lubrication, one of the most desirable solutions is to apply a protective coating or surface treatment to rotating or sliding components to reduce their friction coefficients, thereby leading to reduced wear. Historically, a number of materials such as diamond-like carbon (DLC), titanium nitride (TiN), titanium aluminum nitride (TiAlN), and tungsten carbide (WC) have been examined as tribological coatings. The primary objective of this project was the development of a variety of thin film nanocoatings, derived from the AlMgB14 system, with a focus on reducing wear and friction in both industrial hydraulics and cutting tool applications. Proof-of-concept studies leading up to this project had shown that the constituent phases, AlMgB14 and TiB2, were capable of producing low-friction coatings by pulsed laser deposition. These coatings combine high hardness with a low friction coefficient, and were shown to substantially reduce wear in laboratory tribology tests. Selection of the two applications was based largely on the concept of improved mechanical interface efficiencies for energy conservation. In mobile hydraulic systems, efficiency gains through low friction would translate into improved fuel economy and fewer greenhouse gas emissions. Stationary hydraulic systems, accordingly, would consume less electrical power. Reduced tooling wear in machining operations would translate to greater operating yields, while lowering the energy consumed during processing. The AlMgB14 nanocoatings technology progressed beyond baseline laboratory tests into measurable energy savings and enhancements to product durability. Three key hydraulic markets were identified over the course of the project that will benefit from implementation: industrial vane pumps, orbiting valve-in-star hydraulic motors, and variable displacement piston pumps. In the vane pump application, the overall product efficiency was improved by as much as 11%. Similar results were observed with the hydraulic motors tested, where efficiency gains of over 10% were noted. For variable displacement piston pumps, overall efficiency was improved by 5%. For cutting tools, the most significant gains in productivity (and, accordingly, the efficiency of the machining process as a whole) were associated with the roughing and finishing of titanium components for aerospace systems. Use of the AlMgB14 nanocoating in customer field tests has shown that the coated tools were able to withstand machining rates as high as 500sfm (limited only by the substrate material), with relatively low flank wear when compared to other industrial offerings. AlMgB14 coated tools exhibited a 60% improvement over similarly applied TiAlN thin films. Furthermore, AlMgB14-based coatings in these particular tests lasted twice as long than their TiAlN counterparts at the 500sfm feed rates. Full implementation of the technology into the industrial hydraulic and cutting tool markets equates to a worldwide energy savings of 46 trillion BTU/year by 2030. U.S.-based GHG emissions associated with the markets identified would fall accordingly, dropping by as much as 50,000 tonnes annually.

Clifton B. Higdon III

2011-01-07T23:59:59.000Z

213

The Importance of Domain Size and Purity in High-Efficiency Organic...  

NLE Websites -- All DOE Office Websites (Extended Search)

The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymerorganic photovoltaic cells hinges on excitons-electronhole pairs...

214

Novel metalloporphyrin catalysts for the oxidation of hydrocarbons  

DOE Green Energy (OSTI)

Work was done for developing biomimetic oxidation catalysts. Two classes of metalloporphyrin catalysts were studied. The first class of catalysts studied were a novel series of highly substituted metalloporphyrins, the fluorinated iron dodecaphenylporphyrins. These homogeneous metalloporphyrin catalysts were screened for activity as catalysts in the oxidation of hydrocarbons by dioxygen. Results are discussed with respect to catalyst structural features. The second type of catalysts studied were heterogeneous catalysts consisting of metalloporphyrins applied to inorganic supports. Preliminary catalytic testing results with these materials are presented.

Showalter, M.C.; Nenoff, T.M.; Shelnutt, J.A.

1996-11-01T23:59:59.000Z

215

High Efficiency, Low Emissions Homogeneous Charge Compression Ignition (HCCI) Engines  

SciTech Connect

This is the final report of the High Efficiency Clean Combustion (HECC) Research Program for the U.S. Department of Energy. Work under this co-funded program began in August 2005 and finished in July 2010. The objective of this program was to develop and demonstrate a low emission, high thermal efficiency engine system that met 2010 EPA heavy-duty on-highway truck emissions requirements (0.2g/bhp-hr NOx, 0.14g/bhp-hr HC and 0.01g/bhp-hr PM) with a thermal efficiency of 46%. To achieve this goal, development of diesel homogenous charge compression ignition (HCCI) combustion was the chosen approach. This report summarizes the development of diesel HCCI combustion and associated enabling technologies that occurred during the HECC program between August 2005 and July 2010. This program showed that although diesel HCCI with conventional US diesel fuel was not a feasible means to achieve the program objectives, the HCCI load range could be increased with a higher volatility, lower cetane number fuel, such as gasoline, if the combustion rate could be moderated to avoid excessive cylinder pressure rise rates. Given the potential efficiency and emissions benefits, continued research of combustion with low cetane number fuels and the effects of fuel distillation are recommended. The operation of diesel HCCI was only feasible at part-load due to a limited fuel injection window. A 4% fuel consumption benefit versus conventional, low-temperature combustion was realized over the achievable operating range. Several enabling technologies were developed under this program that also benefited non-HCCI combustion. The development of a 300MPa fuel injector enabled the development of extended lifted flame combustion. A design methodology for minimizing the heat transfer to jacket water, known as precision cooling, will benefit conventional combustion engines, as well as HCCI engines. An advanced combustion control system based on cylinder pressure measurements was developed. A Well-to-wheels analysis of the energy flows in a mobile vehicle system and a 2nd Law thermodynamic analysis of the engine system were also completed under this program.

None

2011-01-31T23:59:59.000Z

216

Catalyst activator  

DOE Patents (OSTI)

A catalyst activator particularly adapted for use in the activation of metal complexes of metals of Group 3-10 for polymerization of ethylenically unsaturated polymerizable monomers, especially olefins, comprising two Group 13 metal or metalloid atoms and a ligand structure including at least one bridging group connecting ligands on the two Group 13 metal or metalloid atoms.

McAdon, Mark H. (Midland, MI); Nickias, Peter N. (Midland, MI); Marks, Tobin J. (Evanston, IL); Schwartz, David J. (Lake Jackson, TX)

2001-01-01T23:59:59.000Z

217

Magnetic Refrigeration Technology for High Efficiency Air Conditioning  

SciTech Connect

Magnetic refrigeration was investigated as an efficient, environmentally friendly, flexible alternative to conventional residential vapor compression central air conditioning systems. Finite element analysis (FEA) models of advanced geometry active magnetic regenerator (AMR) beds were developed to minimize bed size and thus magnet mass by optimizing geometry for fluid flow and heat transfer and other losses. Conventional and magnetocaloric material (MCM) regenerator fabrication and assembly techniques were developed and advanced geometry passive regenerators were built and tested. A subscale engineering prototype (SEP) magnetic air conditioner was designed, constructed and tested. A model of the AMR cycle, combined with knowledge from passive regenerator experiments and FEA results, was used to design the regenerator beds. A 1.5 Tesla permanent magnet assembly was designed using FEA and the bed structure and plenum design was extensively optimized using FEA. The SEP is a flexible magnetic refrigeration platform, with individually instrumented beds and high flow rate and high frequency capability, although the current advanced regenerator geometry beds do not meet performance expectations, probably due to manufacturing and assembly tolerances. A model of the AMR cycle was used to optimize the design of a 3 ton capacity magnetic air conditioner, and the system design was iterated to minimize external parasitic losses such as heat exchanger pressure drop and fan power. The manufacturing cost for the entire air conditioning system was estimated, and while the estimated SEER efficiency is high, the magnetic air conditioning system is not cost competitive as currently configured. The 3 ton study results indicate that there are other applications where magnetic refrigeration is anticipated to have cost advantages over conventional systems, especially applications where magnetic refrigeration, through the use of its aqueous heat transfer fluid, could eliminate intermediate heat exchangers or oil distribution issues found in traditional vapor compression systems.

Boeder, A; Zimm, C

2006-09-30T23:59:59.000Z

218

Catalysts for hydrocarbon conversion  

Science Conference Proceedings (OSTI)

Catalyst, particularly useful in catalytic reforming and for producing highly pure aromatic hydrocarbons, comprising an alumina carrier and containing, expressed in proportion of the weight of the alumina carrier: 005 to 1% of platinum 01 to 4% of gallium, indium or thallium 01 to 2% of tungsten, and 1 to 10% of halogen.

Le P. J.; Malmaison, R.; Marcilly, C.; Martino, G.; Miquel, J.

1980-08-12T23:59:59.000Z

219

Highly Efficient Small Form Factor LED Retrofit Lamp  

SciTech Connect

This report summarizes work to develop a high efficiency LED-based MR16 lamp downlight at OSRAM SYLVANIA under US Department of Energy contract DE-EE0000611. A new multichip LED package, electronic driver, and reflector optic were developed for these lamps. At steady-state, the lamp luminous flux was 409 lumens (lm), luminous efficacy of 87 lumens per watt (LPW), CRI (Ra) of 87, and R9 of 85 at a correlated color temperature (CCT) of 3285K. The LED alone achieved 120 lumens per watt efficacy and 600 lumen flux output at 25 C. The driver had 90% electrical conversion efficiency while maintaining excellent power quality with power factor >0.90 at a power of only 5 watts. Compared to similar existing MR16 lamps using LED sources, these lamps had much higher efficacy and color quality. The objective of this work was to demonstrate a LED-based MR16 retrofit lamp for replacement of 35W halogen MR16 lamps having (1) luminous flux of 500 lumens, (2) luminous efficacy of 100 lumens per watt, (3) beam angle less than 40{sup o} and center beam candlepower of at least 1000 candelas, and (4) excellent color quality.

Steven Allen; Fred Palmer; Ming Li

2011-09-11T23:59:59.000Z

220

Processes for producing low cost, high efficiency silicon solar cells  

DOE Patents (OSTI)

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure.

Rohatgi, Ajeet (Marietta, GA); Doshi, Parag (Altanta, GA); Tate, John Keith (Lawrenceville, GA); Mejia, Jose (Atlanta, GA); Chen, Zhizhang (Duluth, GA)

1998-06-16T23:59:59.000Z

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221

Processes for producing low cost, high efficiency silicon solar cells  

DOE Patents (OSTI)

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime {tau} and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime {tau} and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO{sub x}. In a fourth RTP process, the process of applying front and back contacts is broken up into two separate respective steps, which enhances the efficiency of the cells, at a slight time expense. In a fifth RTP process, a second RTP step is utilized to fire and adhere the screen printed or evaporated contacts to the structure. 28 figs.

Rohatgi, A.; Doshi, P.; Tate, J.K.; Mejia, J.; Chen, Z.

1998-06-16T23:59:59.000Z

222

Processes for producing low cost, high efficiency silicon solar cells  

SciTech Connect

Processes which utilize rapid thermal processing (RTP) are provided for inexpensively producing high efficiency silicon solar cells. The RTP processes preserve minority carrier bulk lifetime .tau. and permit selective adjustment of the depth of the diffused regions, including emitter and back surface field (bsf), within the silicon substrate. Silicon solar cell efficiencies of 16.9% have been achieved. In a first RTP process, an RTP step is utilized to simultaneously diffuse phosphorus and aluminum into the front and back surfaces, respectively, of a silicon substrate. Moreover, an in situ controlled cooling procedure preserves the carrier bulk lifetime .tau. and permits selective adjustment of the depth of the diffused regions. In a second RTP process, both simultaneous diffusion of the phosphorus and aluminum as well as annealing of the front and back contacts are accomplished during the RTP step. In a third RTP process, the RTP step accomplishes simultaneous diffusion of the phosphorus and aluminum, annealing of the contacts, and annealing of a double-layer antireflection/passivation coating SiN/SiO.sub.x.

Rohatgi, Ajeet (Marietta, GA); Chen, Zhizhang (Duluth, GA); Doshi, Parag (Atlanta, GA)

1996-01-01T23:59:59.000Z

223

High Efficiency Driving Electronics for General Illumination LED Luminaires  

SciTech Connect

New generation of standalone LED driver platforms developed, which are more efficient These LED Drivers are more efficient (?90%), smaller in size ( 0.15 in3/watt), lower in cost ( 12 cents/watt in high volumes in millions of units). And these products are very reliable having an operating life of over 50,000 hours. This technology will enable growth of LED light sources in the use. This will also help in energy saving and reducing total life cycle cost of LED units. Two topologies selected for next generation of LED drivers: 1) Value engineered single stage Flyback topology. This is suitable for low powered LED drivers up to 50W power. 2) Two stage boost power factor correction (PFC) plus LLC half bridge platform for higher powers. This topology is suitable for 40W to 300W LED drivers. Three new product platforms were developed to cover a wide range of LED drivers: 1) 120V 40W LED driver, 2) Intellivolt 75W LED driver, & 3) Intellivolt 150W LED driver. These are standalone LED drivers for rugged outdoor lighting applications. Based on these platforms number of products are developed and successfully introduced in the market place meeting key performance, size and cost goals.

Upadhyay, Anand

2012-10-31T23:59:59.000Z

224

Method and Apparatus for High-Efficiency Direct Contact Condensation  

clean energy. But continuing to produce geothermal power efficiently and economically requires innovative adjustments to the technology used to ...

225

High-efficiency photovoltaics based on semiconductor nanostructures  

SciTech Connect

The objective of this project was to exploit a variety of semiconductor nanostructures, specifically semiconductor quantum wells, quantum dots, and nanowires, to achieve high power conversion efficiency in photovoltaic devices. In a thin-film device geometry, the objectives were to design, fabricate, and characterize quantum-well and quantum-dot solar cells in which scattering from metallic and/or dielectric nanostructures was employed to direct incident photons into lateral, optically confined paths within a thin (~1-3um or less) device structure. Fundamental issues concerning nonequilibrium carrier escape from quantum-confined structures, removal of thin-film devices from an epitaxial growth substrate, and coherent light trapping in thin-film photovoltaic devices were investigated. In a nanowire device geometry, the initial objectives were to engineer vertical nanowire arrays to optimize optical confinement within the nanowires, and to extend this approach to core-shell heterostructures to achieve broadspectrum absorption while maintaining high opencircuit voltages. Subsequent work extended this approach to include fabrication of nanowire photovoltaic structures on low-cost substrates.

Yu, Paul K.L. [University of California, San Diego; Yu, Edward T. [University of Texas at Austin; Wang, Deli [University of California, San Diego

2011-10-31T23:59:59.000Z

226

High Efficiency, Ultra-Low Emission, Integrated Process Heater System  

Science Conference Proceedings (OSTI)

The team of TIAX LLC, ExxonMobil Research and Engineering Company, and Callidus Technologies, LLC conducted a six-year program to develop an ultra-low emission process heater burner and an advanced high efficiency heater design. This project addresses the critical need of process heater operators for reliable, economical emission reduction technologies to comply with stringent emission regulations, and for heater design alternatives that reduce process heater energy requirements without significant cost increase. The key project targets were NOx emissions of 10 ppm (@ 3% O2), and a heater thermal efficiency of 95 percent. The ultra low NOx burner was developed through a series of pilot-scale and field tests combined with computational fluid dynamic modeling to arrive at simultaneous low emissions and suitable flame shape and stability. Pilot scale tests were run at TIAX, at the 2 MMBtu/hr scale, and at Callidus at 8 MMBtu/hr. The full scale burner was installed on a 14 burner atmospheric pipestill furnace at an ExxonMobil refinery. A variety of burner configurations, gas tips and flame stabilizers were tested to determine the lowest emissions with acceptable flame shape and stability. The resulting NOx emissions were 22 ppm on average. Starting in 2001, Callidus commercialized the original ultra low NOx burner and made subsequent design improvements in a series of commercial burners evolving from the original concept and/or development. Emissions in the field with the ultra low-NOx burner over a broad spectrum of heater applications have varied from 5 ppm to 30 ppm depending on heater geometry, heater service, fuel and firing capacity. To date, 1550 of the original burners, and 2500 of subsequent generation burners have been sold by Callidus. The advanced heater design was developed by parametric evaluations of a variety of furnace and combustion air preheater configurations and technologies for enhancing convective and radiative heat transfer. The design evolution relied heavily on computational fluid dynamic predictions of design alternatives. The final design features modular separate radiant cells, each with one and two-side fired vertical tubes. The convection section configuration is vertical tube banks enclosed in the radiant channels. Commercial modular plate air preheaters are used. The predicted performance for the integrated advanced heater and Callidus burner is 95 percent efficiency with 9 ppm NOx emissions firing natural gas, and 12 ppm firing refinery gas. The total erected cost is less than a conventional heater with combustion air preheat.

Mason, Howard; Boral, Anindya; Chhotray, San; Martin, Matthew

2006-06-19T23:59:59.000Z

227

SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Efficiency Thermal Energy High-Efficiency Thermal Energy Storage System for CSP to someone by E-mail Share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Facebook Tweet about SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Twitter Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Google Bookmark SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Delicious Rank SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on Digg Find More places to share SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act

228

High-Efficiency Nitride-Based Solid-State Lighting  

SciTech Connect

In this final technical progress report we summarize research accomplished during Department of Energy contract DE-FC26-01NT41203, entitled ''High-Efficiency Nitride-Based Solid-State Lighting''. Two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and the Lighting Research Center at Rensselaer Polytechnic Institute (led by Dr. N. Narendran), pursued the goals of this contract from thin film growth, characterization, and packaging/luminaire design standpoints. The UCSB team initially pursued the development of blue gallium nitride (GaN)-based vertical-cavity surface-emitting lasers, as well as ultraviolet GaN-based light emitting diodes (LEDs). In Year 2, the emphasis shifted to resonant-cavity light emitting diodes, also known as micro-cavity LEDs when extremely thin device cavities are fabricated. These devices have very directional emission and higher light extraction efficiency than conventional LEDs. Via the optimization of thin-film growth and refinement of device processing, we decreased the total cavity thickness to less than 1 {micro}m, such that micro-cavity effects were clearly observed and a light extraction efficiency of over 10% was reached. We also began the development of photonic crystals for increased light extraction, in particular for so-called ''guided modes'' which would otherwise propagate laterally in the device and be re-absorbed. Finally, we pursued the growth of smooth, high-quality nonpolar a-plane and m-plane GaN films, as well as blue light emitting diodes on these novel films. Initial nonpolar LEDs showed the expected behavior of negligible peak wavelength shift with increasing drive current. M-plane LEDs in particular show promise, as unpackaged devices had unsaturated optical output power of {approx} 3 mW at 200 mA drive current. The LRC's tasks were aimed at developing the subcomponents necessary for packaging UCSB's light emitting diodes, and packaging them to produce a white light fixture. During the third and final year of the project, the LRC team investigated alternate packaging methods for the white LED device to achieve at least 25 percent more luminous efficacy than traditional white LEDs; conducted optical ray-tracing analyses and human factors studies to determine the best form factor for the white light source under development, in terms of high luminous efficacy and greater acceptance by subjects; and developed a new die encapsulant using silicone-epoxy resins that showed less yellowing and slower degradation. At the conclusion of this project, the LRC demonstrated a new packaging method, called scattered photon extraction (SPE), that produced an average luminous flux and corresponding average efficacy of 90.7 lm and 36.3 lm/W, respectively, compared with 56.5 lm and 22.6 lm/W for a similar commercial white LED package. At low currents, the SPE package emitted white light with an efficacy of over 80 lm/W and had chromaticity values very close to the blackbody locus. The SPE package showed an overall improvement of 61% for this particular comparison, exceeding the LRC's third-year goal of 25% improvement.

Paul T. Fini; Shuji Nakamura

2005-07-30T23:59:59.000Z

229

Autothermal reforming catalyst having perovskite structure  

DOE Patents (OSTI)

The invention addressed two critical issues in fuel processing for fuel cell application, i.e. catalyst cost and operating stability. The existing state-of-the-art fuel reforming catalyst uses Rh and platinum supported over refractory oxide which add significant cost to the fuel cell system. Supported metals agglomerate under elevated temperature during reforming and decrease the catalyst activity. The catalyst is a perovskite oxide or a Ruddlesden-Popper type oxide containing rare-earth elements, catalytically active firs row transition metal elements, and stabilizing elements, such that the catalyst is a single phase in high temperature oxidizing conditions and maintains a primarily perovskite or Ruddlesden-Popper structure under high temperature reducing conditions. The catalyst can also contain alkaline earth dopants, which enhance the catalytic activity of the catalyst, but do not compromise the stability of the perovskite structure.

Krumpel, Michael (Naperville, IL); Liu, Di-Jia (Naperville, IL)

2009-03-24T23:59:59.000Z

230

Development of manufacturing capability for high-concentration, high-efficiency silicon solar cells  

DOE Green Energy (OSTI)

This report presents a summary of the major results from a program to develop a manufacturable, high-efficiency silicon concentrator solar cell and a cost-effective manufacturing facility. The program was jointly funded by the Electric Power Research Institute, Sandia National Laboratories through the Concentrator Initiative, and SunPower Corporation. The key achievements of the program include the demonstration of 26%-efficient silicon concentrator solar cells with design-point (20 W/cm{sup 2}) efficiencies over 25%. High-performance front-surface passivations; that were developed to achieve this result were verified to be absolutely stable against degradation by 475 days of field exposure at twice the design concentration. SunPower demonstrated pilot production of more than 1500 of these cells. This cell technology was also applied to pilot production to supply 7000 17.7-cm{sup 2} one-sun cells (3500 yielded wafers) that demonstrated exceptional quality control. The average efficiency of 21.3% for these cells approaches the peak efficiency ever demonstrated for a single small laboratory cell within 2% (absolute). Extensive cost models were developed through this program and calibrated by the pilot-production project. The production levels achieved indicate that SunPower could produce 7-10 MW of concentrator cells per year in the current facility based upon the cell performance demonstrated during the program.

Sinton, R.A.; Verlinden, P.J.; Crane, R.A.; Swanson, R.N. [SunPower Corp., Sunnyvale, CA (United States)

1996-10-01T23:59:59.000Z

231

Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion  

SciTech Connect

The project which extended from November 2005 to May of 2010 demonstrated the application of Low Temperature Combustion (LTC) with engine out NOx levels of 0.2 g/bhp-hr throughout the program target load of 12.6bar BMEP. The project showed that the range of loads could be extended to 16.5bar BMEP, therefore matching the reference lug line of the base 2007 MY Navistar 6.4L V8 engine. Results showed that the application of LTC provided a dramatic improvement over engine out emissions when compared to the base engine. Furthermore LTC improved thermal efficiency by over 5% from the base production engine when using the steady state 13 mode composite test as a benchmark. The key enablers included improvements in the air, fuel injection, and cooling systems made in Phases I and II. The outcome was the product of a careful integration of each component under an intelligent control system. The engine hardware provided the conditions to support LTC and the controller provided the necessary robustness for a stable combustion. Phase III provided a detailed account on the injection strategy used to meet the high load requirements. During this phase, the control strategy was implemented in a production automotive grade ECU to perform cycle-by-cycle combustion feedback on each of the engine cylinders. The control interacted on a cycle base with the injection system and with the Turbo-EGR systems according to their respective time constants. The result was a unique system that could, first, help optimize the combustion system and maintain high efficiency, and secondly, extend the steady state results to the transient mode of operation. The engine was upgraded in Phase IV with a Variable Valve Actuation system and a hybrid EGR loop. The impact of the more versatile EGR loop did not provide significant advantages, however the application of VVA proved to be an enabler to further extend the operation of LTC and gain considerable benefits in fuel economy and soot reduction. Finally, the transient demonstration was performed in Phase IV. The project demonstrated the achievement of meeting US10 emissions without NOx aftertreatment. The successful execution of the project has served to highlight the effectiveness of closely matched combustion predictive tools to engine testing. It has further served to highlight the importance of key technologies and future areas of research and development. In this regard, recommendations are made towards further improvements in the areas of engine hardware, fuel injection systems, controls and fuels.

Ojeda, William de

2010-07-31T23:59:59.000Z

232

Project: Novel Working Fluids for High-Efficiency HVAC&R ...  

Science Conference Proceedings (OSTI)

... of the best replacements for high-GWP hydrofluorocarbon (HFC) refrigerants; and to demonstrate improved energy efficiency of chillers through ...

2012-12-27T23:59:59.000Z

233

Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalystes to Poisons form High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures  

DOE Green Energy (OSTI)

There has been a recent shift in interest in converting not only natural gas and coal derived syngas to Fischer-Tropsch synthesis products, but also converting biomass-derived syngas, as well as syngas derived from coal and biomass mixtures. As such, conventional catalysts based on iron and cobalt may not be suitable without proper development. This is because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using entrained-flow oxygen-blown gasifier gasification gasification) than solely from coal, other compounds may actually be increased. Of particular concern are compounds containing alkali chemicals like the chlorides of sodium and potassium. In the first year, University of Kentucky Center for Applied Energy Research (UK-CAER) researchers completed a number of tasks aimed at evaluating the sensitivity of cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts and a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to alkali halides. This included the preparation of large batches of 0.5%Pt-25%Co/Al{sub 2}O{sub 3} and 100Fe: 5.1Si: 3.0K: 2.0Cu (high alpha) catalysts that were split up among the four different entities participating in the overall project; the testing of the catalysts under clean FT and WGS conditions; the testing of the Fe-Cr WGS catalyst under conditions of co-feeding NaCl and KCl; and the construction and start-up of the continuously stirred tank reactors (CSTRs) for poisoning investigations.

Burton Davis; Gary Jacobs; Wenping Ma; Khalid Azzam; Janet ChakkamadathilMohandas; Wilson Shafer

2009-09-30T23:59:59.000Z

234

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS/CO2  

DOE Green Energy (OSTI)

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the small-diameter ({approx}1/32 inch) catalyst particles have enough mechanical strength to avoid loss by attrition. However, all of the State Of The Art (SOTA) catalysts and advanced catalysts for the purpose are low in mechanical strength. The patented carbon-coated catalyst technology developed in our laboratory converts catalyst particles with low mechanical strength to strong catalysts suitable for ebullated bed application. This R&D program is concerned with the modification on the mechanical strength of the SOTA and advanced catalysts so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO{sub 2} efficiently and economically. The objective of this R&D program is to study the technical and economic feasibility of selective production of high-value oxygenated chemicals from synthesis gas and CO{sub 2} mixed feed in an ebullated bed reactor using carbon-coated catalyst particles.

Peizheng Zhou

2001-10-26T23:59:59.000Z

235

CARBON COATED (CARBONOUS) CATALYST IN EBULLATED BED REACTOR FOR PRODUCTION OF OXYGENATED CHEMICALS FROM SYNGAS/CO2  

DOE Green Energy (OSTI)

There are a number of exothermic chemical reactions which might benefit from the temperature control and freedom from catalyst fouling provided by the ebullated bed reactor technology. A particularly promising area is production of oxygenated chemicals, such as alcohols and ethers, from synthesis gas, which can be economically produced from coal or biomass. The ebullated bed operation requires that the small-diameter ({approx} 1/32 inch) catalyst particles have enough mechanical strength to avoid loss by attrition. However, all of the State Of The Art (SOTA) catalysts and advanced catalysts for the purpose are low in mechanical strength. The patented carbon-coated catalyst technology developed in our laboratory converts catalyst particles with low mechanical strength to strong catalysts suitable for ebullated bed application. This R&D program is concerned with the modification on the mechanical strength of the SOTA and advanced catalysts so that the ebullated bed technology can be utilized to produce valuable oxygenated chemicals from syngas/CO{sub 2} efficiently and economically. The objective of this R&D program is to study the technical and economic feasibility of selective production of high-value oxygenated chemicals from synthesis gas and CO{sub 2} mixed feed in an ebullated bed reactor using carbon-coated catalyst particles.

Peizheng Zhou

2000-11-17T23:59:59.000Z

236

Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalysts to Poisons from High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures  

Science Conference Proceedings (OSTI)

There has been a recent shift in interest in converting not only natural gas and coal derived syngas to Fischer-Tropsch synthesis products, but also converting biomass-derived syngas, as well as syngas derived from coal and biomass mixtures. As such, conventional catalysts based on iron and cobalt may not be suitable without proper development. This is because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using entrained-flow oxygen-blown gasifier gasification gasification) than solely from coal, other compounds may actually be increased. Of particular concern are compounds containing alkali chemicals like the chlorides of sodium and potassium. In the first year, University of Kentucky Center for Applied Energy Research (UK-CAER) researchers completed a number of tasks aimed at evaluating the sensitivity of cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts and a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to alkali halides. This included the preparation of large batches of 0.5%Pt-25%Co/Al{sub 2}O{sub 3} and 100Fe: 5.1Si: 3.0K: 2.0Cu (high alpha) catalysts that were split up among the four different entities participating in the overall project; the testing of the catalysts under clean FT and WGS conditions; the testing of the Fe-Cr WGS catalyst under conditions of co-feeding NaCl and KCl; and the construction and start-up of the continuously stirred tank reactors (CSTRs) for poisoning investigations. In the second and third years, researchers from the University of Kentucky Center for Applied Energy Research (UK-CAER) continued the project by evaluating the sensitivity of a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to a number of different compounds, including KHCO{sub 3}, NaHCO{sub 3}, HCl, HBr, HF, H{sub 2}S, NH{sub 3}, and a combination of H{sub 2}S and NH{sub 3}. Cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts were also subjected to a number of the same compounds in order to evaluate their sensitivities at different concentration levels of added contaminant.

Burton Davis; Gary Jacobs; Wenping Ma; Dennis Sparks; Khalid Azzam; Janet Chakkamadathil Mohandas; Wilson Shafer; Venkat Ramana Rao Pendyala

2011-09-30T23:59:59.000Z

237

Design of Bulk Nanocomposites as High Efficiency Thermoelectric...  

Office of Science (SC) Website

structure as the host material breaks thermoelectric efficiency records by blocking thermal, but not electrical, conductivity. Significance and Impact A new strategy to design...

238

High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency  

E-Print Network (OSTI)

tools to evaluate cost and energy implications of efficiencytools to evaluate cost and energy implications of efficiencyand low first cost, not energy efficiency. Utilization of “

Singer, Brett C.

2010-01-01T23:59:59.000Z

239

Rational Device Design for Highly Efficient Organic Photovoltaic Solar Cells.  

E-Print Network (OSTI)

??Abundant, scalable, environmentally-friendly organic photovoltaic (OPV) technology is increasingly promising in recent years. The power conversion efficiency (PCE) of OPVs has been raised to around… (more)

Yang, Bin

2013-01-01T23:59:59.000Z

240

High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency  

E-Print Network (OSTI)

for efficient and meaningful sub-metering. • Develop&architecture to facilitate sub-metering • Include sub-metersintermingled, making sub-metering expensive and complicated.

Singer, Brett C.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

High Efficiency Multiple-Junction Solar Cells - Energy ...  

Technology Marketing Summary Single junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific ...

242

Available Technologies: Highly Efficient Multigap Solar Cell Materials  

Scientists at Berkeley Lab have invented multiband gap semiconducting materials for developing solar cells that could achieve power conversion efficiencies of 50 ...

243

Highly efficient 6-stroke engine cycle with water injection  

combustion piston engine. The increased efficiency is a result of recovering heat primarily from the engine exhaust gases, and also from the engine coolant.

244

Southwest Gas Corporation - Commercial High-Efficiency Equipment...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

who purchase energy efficient natural gas equipment. Eligible equipment includes natural gas storage and tankless water heaters, boiler equipment, griddles, fryers, conveyor ovens,...

245

Sandia National Laboratories High Efficiency Multiple-Junction ...  

Sandia National Laboratories TECHNOLOGY SUMMARY Single junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific

246

HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING  

SciTech Connect

In this second annual report we summarize the progress in the second-year period of Department of Energy contract DE-FC26-01NT41203, entitled ''High- Efficiency Nitride-Based Solid-State Lighting''. The two teams, from the University of California at Santa Barbara (Principle Investigator: Dr. Shuji Nakamura) and Rensselaer Polytechnic Institute (led by Dr. N. Narendran), are pursuing the goals of this contract from thin film growth, characterization, and packaging standpoints. The UCSB team has recently made significant progress in the development of light-emitting diodes (LEDs) with AlGaN active regions emitting in the ultraviolet (UV), resonant-cavity LEDs (RCLEDs), as well as lateral epitaxial overgrowth (LEO) techniques to obtain large-area non-polar GaN films with low average dislocation density. The Rensselaer team has benchmarked the performance of commercially available LED systems and has also conducted efforts to develop an optimized RCLED packaging scheme, including development of advanced epoxy encapsulant chemistries.

Paul T. Fini; Shuji Nakamura

2003-10-30T23:59:59.000Z

247

Novel Morphology of Highly Efficient Two-phase Ferrite Cores for ...  

Science Conference Proceedings (OSTI)

This discovery may very well usher in a new chapter in high efficiency power cores for high frequency inductors, transformers, power supplies, converters, and

248

EVALUATION OF A LOW FRICTION - HIGH EFFICIENCY ROLLER BEARING ENGINE  

SciTech Connect

This Low Friction (High Efficiency Roller Bearing) Engine (LFE) report presents the work done by The Timken Company to conduct a technology demonstration of the benefits of replacing hydrodynamic bearings with roller bearings in the crankshaft and camshaft assemblies of an internal combustion engine for the purpose of collecting data sufficient to prove merit. The engines in the present study have been more extensively converted to roller bearings than any previous studies (40 needle roller bearings per engine) to gain understanding of the full potential of application of bearing technology. The project plan called for comparative testing of a production vehicle which was already respected for having demonstrated low engine friction levels with a rollerized version of that engine. Testing was to include industry standard tests for friction, emissions and fuel efficiency conducted on instrumented dynamometers. Additional tests for fuel efficiency, cold start resistance and other measures of performance were to be made in the actual vehicle. Comparative measurements of noise, vibration and harshness (NVH), were planned, although any work to mitigate the suspected higher NVH level in the rollerized engine was beyond the scope of this project. Timken selected the Toyota Avalon with a 3.5L V-6 engine as the test vehicle. In an attempt to minimize cost and fabrication time, a ‘made-from’ approach was proposed in which as many parts as possible would be used or modified from production parts to create the rollerized engine. Timken commissioned its test partner, FEV Engine Technology, to do a feasibility study in which they confirmed that using such an approach was possible to meet the required dimensional restrictions and tolerances. In designing the roller bearing systems for the crank and cam trains, Timken utilized as many production engine parts as possible. The crankshafts were produced from production line forgings, which use Timken steel, modified with special machining and heat treatment. Timken designed and manufactured all of the roller bearing related components such as the thrust bearing package. The production connecting rods and camshafts could not be used for the roller bearing engine, so new ones were produced according to the team’s designs using Timken steel. The remaining miscellaneous components were designed and procured by FEV. Timken prepared a display version of the crankshaft portion of the production engine without connecting rods which could be driven by a motor through a cogged-belt and electrically actuated clutch arrangement. A modified version was also made in which the engine was outfitted with roller bearings on the main bearing positions. Preliminary tests showed that the rollerized engine was running with 1/3 less friction than the standard display engine. Additional friction testing and noise characterization was cut short because of shipping damage to the rollerized engine display and because of other project priorities. The team did successfully demonstrate the ability to package roller bearings satisfactorily in numerous locations in a typical automotive engine. The scope of this project did not include durability demonstration and that subject would have to be addressed in any follow-on work. In the actual test phase, the rollerized engine did show significantly less friction in motored dynamometer tests compared to its production equivalent. The 5-10% improvement measured in this study was about half that seen in other studies. However, the fired test results did not show a reduction in friction which did not match prior experience or expectations. Subsequent teardown and inspection of the rollerized engine revealed potential sources of excessive friction in the experimental application. These features would be eliminated in a design not based on modification of production parts. The team is confident (based on experience) that friction reduction would be realized with proper modifications.

Kolarik, Robert V. II; Shattuck, Charles W.; Copper, Anthony P.

2009-06-30T23:59:59.000Z

249

The Existence of Quantum Entanglement Catalysts  

E-Print Network (OSTI)

Without additional resources, it is often impossible to transform one entangled quantum state into another with local quantum operations and classical communication. Jonathan and Plenio [Phys. Rev. Lett. 83, 3566(1999)] presented an interesting example showing that the presence of another state, called a catalyst, enables such a transformation without changing the catalyst. They also pointed out that in general it is very hard to find an analytical condition under which a catalyst exists. In this paper we study the existence of catalysts for two incomparable quantum states. For the simplest case of $2\\times 2$ catalysts for transformations from one $4\\times 4$ state to another, a necessary and sufficient condition for existence is found. For the general case, we give an efficient polynomial time algorithm to decide whether a $k\\times k$ catalyst exists for two $n\\times n$ incomparable states, where $k$ is treated as a constant.

Xiaoming Sun; Runyao Duan; Mingsheng Ying

2003-11-19T23:59:59.000Z

250

Hydrogen Production via a High-Efficiency Low-Temperature Reformer  

Science Conference Proceedings (OSTI)

Fuel cells are promoted by the US government as a viable alternative for clean and efficient energy generation. It is anticipated that the fuel cell market will rise if the key technical barriers can be overcome. One of them is certainly fuel processing and purification. Existing fuel reforming processes are energy intensive, extremely complicated and capital intensive; these disadvantages handicap the scale-down of existing reforming process, targeting distributed or on-board/stationary hydrogen production applications. Our project involves the bench-scale demonstration of a high-efficiency low-temperature steam reforming process. Hydrogen production can be operated at 350 to 400ºC with our invention, as opposed to >800ºC of existing reforming. In addition, our proposed process improves the start-up deficiency of conventional reforming due to its low temperature operation. The objective of this project is to demonstrate the invented process concept via a bench scale unit and verify mathematical simulation for future process optimization study. Under this project, we have performed the experimental work to determine the adsorption isotherm, reaction kinetics, and membrane permeances required to perform the process simulation based upon the mathematical model developed by us. A ceramic membrane coated with palladium thin film fabricated by us was employed in this study. The adsorption isotherm for a selected hydrotalcite adsorbent was determined experimentally. Further, the capacity loss under cyclic adsorption/desorption was confirmed to be negligible. Finally a commercial steam reforming catalyst was used to produce the reaction kinetic parameters required for the proposed operating condition. With these input parameters, a mathematical simulation was performed to predict the performance of the invented process. According to our simulation, our invented hybrid process can deliver 35 to 55% methane conversion, in comparison with the 12 and 18-21% conversion of the packed bed and an adsorptive reactor respectively. In addition CO contamination with energy savings and ~50% capital savings over conventional reforming for fuel cell applications. The pollution abatement potential associated with the implementation of fuel cells, including the elimination of nitrogen oxides and CO, and the reduction in volatile organics and CO2, can thus be realized with the implementation of this invented process. The projected total market size for equipment sale for the proposed process in US is $1.5 billion annually.

Paul KT Liu; Theo T. Tsotsis

2006-05-31T23:59:59.000Z

251

Solid Catalyst – Alkylation  

This is a method used to reactivate solid/liquid catalysts used in INL’s super critical process to produce alkylates. The method brings the catalyst ...

252

Design of a high activity and selectivity alcohol catalyst. Seventh quarterly report, February 7, 1992--May 7, 1992  

DOE Green Energy (OSTI)

In order to explore the secondary dehydration of methanol over {gamma}-Al{sub 2}O{sub 3} support and over bimetallic Rh-Mo/{gamma}- Al{sub 2}O{sub 3}, a new series of K-doped Rh-Mo/{gamma}-Al{sub 2}O{sub 3} catalysts was synthesized. Work on synthesis of bimetallic Rh-Mo clusters is reported.

Foley, H.C.; Mills, G.A.

1992-06-04T23:59:59.000Z

253

Hydrogen Production via a High-Efficiency Low-Temperature Reformer  

DOE Green Energy (OSTI)

Fuel cells are promoted by the US government as a viable alternative for clean and efficient energy generation. It is anticipated that the fuel cell market will rise if the key technical barriers can be overcome. One of them is certainly fuel processing and purification. Existing fuel reforming processes are energy intensive, extremely complicated and capital intensive; these disadvantages handicap the scale-down of existing reforming process, targeting distributed or on-board/stationary hydrogen production applications. Our project involves the bench-scale demonstration of a high-efficiency low-temperature steam reforming process. Hydrogen production can be operated at 350 to 400ºC with our invention, as opposed to >800ºC of existing reforming. In addition, our proposed process improves the start-up deficiency of conventional reforming due to its low temperature operation. The objective of this project is to demonstrate the invented process concept via a bench scale unit and verify mathematical simulation for future process optimization study. Under this project, we have performed the experimental work to determine the adsorption isotherm, reaction kinetics, and membrane permeances required to perform the process simulation based upon the mathematical model developed by us. A ceramic membrane coated with palladium thin film fabricated by us was employed in this study. The adsorption isotherm for a selected hydrotalcite adsorbent was determined experimentally. Further, the capacity loss under cyclic adsorption/desorption was confirmed to be negligible. Finally a commercial steam reforming catalyst was used to produce the reaction kinetic parameters required for the proposed operating condition. With these input parameters, a mathematical simulation was performed to predict the performance of the invented process. According to our simulation, our invented hybrid process can deliver 35 to 55% methane conversion, in comparison with the 12 and 18-21% conversion of the packed bed and an adsorptive reactor respectively. In addition CO contamination with <10 to 120 ppm is predicted for the invented process depending upon the cycle time for the PSA type operation. In comparison, the adsorption reactor can also deliver a similar CO contaminant at the low end; however, its high end reaches as high as 300 ppm based upon the simulation of our proposed operating condition. Our experimental results for the packed bed and the membrane reactor deliver 12 and 18% conversion at 400°C, approaching the conversion by the mathematical simulation. Due to the time constraint, the experimental study on the conversion of the invented process has not been complete. However, our in-house study using a similar process concept for the water gas shift reaction has demonstrated the reliability of our mathematical simulation for the invented process. In summary, we are confident that the invented process can deliver efficiently high purity hydrogen at a low temperature (~400°C). According to our projection, the invented process can further achieve 5% energy savings and ~50% capital savings over conventional reforming for fuel cell applications. The pollution abatement potential associated with the implementation of fuel cells, including the elimination of nitrogen oxides and CO, and the reduction in volatile organics and CO2, can thus be realized with the implementation of this invented process. The projected total market size for equipment sale for the proposed process in US is $1.5 billion annually.

Paul KT Liu; Theo T. Tsotsis

2006-05-31T23:59:59.000Z

254

Design and global optimization of high-efficiency thermophotovoltaic systems  

E-Print Network (OSTI)

Despite their great promise, small experimental thermophotovoltaic (TPV) systems at 1000 K generally exhibit extremely low power conversion efficiencies (approximately 1%), due to heat losses such as thermal emission of ...

Bermel, Peter A.

255

Required Materials Properties for High-Efficiency CIGS Modules: Preprint  

DOE Green Energy (OSTI)

This paper discusses material properties required for each CIGS device layer so that large-area CIGS modules can achieve efficiencies of >15%, substantially higher than the current state of the art.

Repins, I.; Glynn, S.; Duenow, J.; Coutts, T. J.; Metzger, W.; Contreras, M. A.

2009-07-01T23:59:59.000Z

256

Program on Technology Innovation: Very High Efficiency Photovoltaics Research, 2009 Update  

Science Conference Proceedings (OSTI)

This is the second interim annual summary report on the collaborative activities of CNRS and EDF RD to advance the state of high-efficiency photovoltaics (PV). This activity is principally concerned with basic research to enhance longer-term prospects of very high efficiency PV, but it also includes possible nearer-term outcomes of improved conversion efficiency for existing technologies.

2010-02-19T23:59:59.000Z

257

Novel Reforming Catalysts  

Science Conference Proceedings (OSTI)

Aqueous phase reforming is useful for processing oxygenated hydrocarbons to hydrogen and other more useful products. Current processing is hampered by the fact that oxide based catalysts are not stable under high temperature hydrothermal conditions. Silica in the form of structured MCM-41 is thermally a more stable support for Co and Ni than conventional high surface area amorphous silica but hydrothermal stability is not demonstrated. Carbon nanotube supports, in contrast, are highly stable under hydrothermal reaction conditions. In this project we show that carbon nanotubes are stable high activity/selectivity supports for the conversion of ethylene glycol to hydrogen.

Pfefferle, Lisa D; Haller, Gary L

2012-10-16T23:59:59.000Z

258

SunShot Initiative: High-Efficiency Thermal Storage System for...  

NLE Websites -- All DOE Office Websites (Extended Search)

Efficiency Thermal Storage System for Solar Plants to someone by E-mail Share SunShot Initiative: High-Efficiency Thermal Storage System for Solar Plants on Facebook Tweet about...

259

Separation of Fischer-Tropsch Wax Products from Ultrafine Iron Catalyst Particles  

Science Conference Proceedings (OSTI)

A fundamental filtration study was started to investigate the separation of Fischer-Tropsch Synthesis (FTS) liquids from iron-based catalyst particles. Slurry-phase FTS in slurry bubble column reactor systems is the preferred mode of operation since the reaction is highly exothermic. Consequently, heavy wax products in one approach may be separated from catalyst particles before being removed from the reactor system. Achieving an efficient wax product separation from iron-based catalysts is one of the most challenging technical problems associated with slurry-phase iron-based FTS and is a key factor for optimizing operating costs. The separation problem is further compounded by attrition of iron catalyst particles and the formation of ultra-fine particles.

Amitava Sarkar; James K. Neathery; Burtron H. Davis

2006-12-31T23:59:59.000Z

260

Low temperature steam-coal gasification catalysts  

SciTech Connect

Shrinking domestic supplies and larger dependence on foreign sources have made an assortment of fossil fuels attractive as possible energy sources. The high sulfur and mineral coals of Illinois would be an ideal candidate as possible gasification feedstock. Large reserves of coal as fossil fuel source and a projected shortage of natural gas (methane) in the US, have made development of technology for commercial production of high Btu pipeline gases from coal of interest. Several coal gasification processes exist, but incentives remain for the development of processes that would significantly increase efficiency and lower cost. A major problem in coal/char gasification is the heat required which make the process energy intensive. Hence, there is a need for an efficient and thermally neutral gasification process. Results are described for the gasification of an Illinois No. 6 coal with transition metal catalysts and added potassium hydroxide.

Hippo, E.J.; Tandon, D. [Southern Illinois Univ., Carbondale, IL (United States)

1996-12-31T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

High-Efficiency, High-Capacity, Low-NOx Aluminum Melting Using Oxygen-Enhanced Combustion  

SciTech Connect

This report describes the development and application of a novel oxygen enhanced combustion system with an integrated vacuum swing adsorption (VSA) oxygen supply providing efficient, low NOx melting in secondary aluminum furnaces. The mainstay of the combustion system is a novel air-oxy-natural gas burner that achieves high productivity and energy efficiency with low NOx emissions through advanced mixing concepts and the use of separate high- and low-purity oxidizer streams. The technology was installed on a reverberatory, secondary aluminum melting plant at the Wabash Aluminum Alloy's Syracuse, N.Y. plant, where it is currently in operation. Field testing gave evidence that the new burner technology meets the stringent NOx emissions target of 0.323 lb NO2/ton aluminum, thus complying with regulations promulgated by Southern California's South Coast Air Quality Management District (SCAQMD). Test results also indicated that the burner technology exceeded fuel efficiency and melting capacity goals. Economic modeling showed that the novel air-oxy-fuel (ADF) combustion technology provides a substantial increase in furnace profitability relative to air-fuel operation. Model results also suggest favorable economics for the air-oxy-fuel technology relative to a full oxy-fuel conversion of the furnace.

D'Agostini, M.D.

2000-06-02T23:59:59.000Z

262

High efficiency carbonate fuel cell/turbine hybrid power cycles  

SciTech Connect

Carbonate fuel cells developed in commercial 2.85 MW size, have an efficiency of 57.9%. Studies of higher efficiency hybrid power cycles were conducted to identify an economically competitive system and an efficiency over 65%. A hybrid power cycle was identified that includes a direct carbonate fuel cell, a gas turbine, and a steam cycle, which generates power at a LHV efficiency over 70%; it is called a Tandem Technology Cycle (TTC). In a TTC operating on natural gas fuel, 95% of the fuel is mixed with recycled fuel cell anode exhaust, providing water for reforming the fuel, and flows to a direct carbonate fuel cell system which generates 72% of the power. The portion of fuel cell anode exhaust not recycled, is burned and heat is transferred to compressed air from a gas turbine, heating it to 1800 F. The stream is then heated to 2000 F in gas turbine burner and expands through the turbine generating 13% of the power. Half the gas turbine exhaust flows to anode exhaust burner and the rest flows to the fuel cell cathodes providing the O2 and CO2 needed in the electrochemical reaction. Studies of the TTC for 200 and 20 MW size plants quantified performance, emissions and cost-of-electricity, and compared the TTC to gas turbine combined cycles. A 200-MW TTC plant has an efficiency of 72.6%; estimated cost of electricity is 45.8 mills/kWhr. A 20-MW TTC plant has an efficiency of 65.2% and a cost of electricity of 50 mills/kWhr.

Steinfeld, G.

1996-12-31T23:59:59.000Z

263

Small core axial compressors for high efficiency jet aircraft  

E-Print Network (OSTI)

This thesis quantifies mechanisms that limit efficiency in small core axial compressors, defined here as compressor exit corrected flow between 1.5 and 3.0 lbm/s. The first part of the thesis describes why a small engine ...

DiOrio, Austin Graf

2012-01-01T23:59:59.000Z

264

High efficiency thin-film multiple-gap photovoltaic device  

SciTech Connect

A photovoltaic device includes at least two solar cells made from Group IV elements or their alloys in the amorphous state mounted on a substrate. The outermost or first cell has a larger bandgap than the second cell. Various techniques are utilized to improve the efficiency of the device.

Dalal, Vikram L. (Newark, DE)

1983-01-01T23:59:59.000Z

265

Highly efficient 6-stroke engine cycle with water injection  

Science Conference Proceedings (OSTI)

A six-stroke engine cycle having improved efficiency. Heat is recovered from the engine combustion gases by using a 6-stroke engine cycle in which combustion gases are partially vented proximate the bottom-dead-center position of the fourth stroke cycle, and water is injected proximate the top-dead-center position of the fourth stroke cycle.

Szybist, James P; Conklin, James C

2012-10-23T23:59:59.000Z

266

Power Efficiency in High Performance Computing Shoaib Kamil  

E-Print Network (OSTI)

of 192 cores per cabinet. The power feed to each cabinet is 208 VAC 3-phase and is capable of handling 25 KW per rack. Each cabinet has a single 92 percent efficient power supply at the bottom of the rack system performance (ssp) metric. LBNL Tech Report 58868, 2005. [13] L. Oliker, A. Canning, J. Carter, J

267

Electrochemical catalyst recovery method  

DOE Patents (OSTI)

A method of recovering catalyst material from latent catalyst material solids includes: a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications.

Silva, Laura J. (Richland, WA); Bray, Lane A. (Richland, WA)

1995-01-01T23:59:59.000Z

268

Electrochemical catalyst recovery method  

DOE Patents (OSTI)

A method of recovering catalyst material from latent catalyst material solids includes: (a) combining latent catalyst material solids with a liquid acid anolyte solution and a redox material which is soluble in the acid anolyte solution to form a mixture; (b) electrochemically oxidizing the redox material within the mixture into a dissolved oxidant, the oxidant having a potential for oxidation which is effectively higher than that of the latent catalyst material; (c) reacting the oxidant with the latent catalyst material to oxidize the latent catalyst material into at least one oxidized catalyst species which is soluble within the mixture and to reduce the oxidant back into dissolved redox material; and (d) recovering catalyst material from the oxidized catalyst species of the mixture. The invention is expected to be particularly useful in recovering spent catalyst material from petroleum hydroprocessing reaction waste products having adhered sulfides, carbon, hydrocarbons, and undesired metals, and as well as in other industrial applications. 3 figs.

Silva, L.J.; Bray, L.A.

1995-05-30T23:59:59.000Z

269

Catalysts for improved fuel processing  

DOE Green Energy (OSTI)

This report covers our technical progress on fuel processing catalyst characterization for the specific purpose of hydrogen production for proton-exchange-membrane (PEM) fuel cells. These development efforts support DOE activities in the development of compact, transient capable reformers for on-board hydrogen generation starting from candidate fuels. The long-term objective includes increased durability and lifetime, in addition to smaller volume, improved performance, and other specifications required meeting fuel processor goals. The technical barriers of compact fuel processor size, transient capability, and compact, efficient thermal management all are functions of catalyst performance. Significantly, work at LANL now tests large-scale fuel processors for performance and durability, as influenced by fuels and fuel constituents, and complements that testing with micro-scale catalyst evaluation which is accomplished under well controlled conditions.

Borup, R.L.; Inbody, M.A. [and others

2000-09-01T23:59:59.000Z

270

High-efficiency large-area CdTe panels  

DOE Green Energy (OSTI)

The objective of this three year effort has been to develop an improved materials technology and fabrication process for limited volume production of 1 ft{sup 2} and 4 ft{sup 2} CdS/CdTe photovoltaic modules. The module stability objective by the end of this three year subcontract was to develop techniques to provide ten year life exploration with no greater than 10% degradation. In order to achieve these efficiency and stability objectives, the research program has been separated into tasks including: (1) analysis and characterization of CdS/CdTe Devices; (2) performance optimization on small cells; (3) encapsulation and stability testing; and (4) module efficiency optimization. 27 refs., 18 figs., 3 tabs.

Albright, S.P.; Chamberlin, R.R.; Jordan, J.F. (Photon Energy, Inc., El Paso, TX (USA))

1990-11-01T23:59:59.000Z

271

High-efficiency free-electron laser results  

Science Conference Proceedings (OSTI)

Results obtained with a tapered-wiggler free-electron laser demonstrate the concepts proposed by Morton for enhanced efficiency and show deceleration of electrons by as much as 7%, and extraction of more than 3% of the total electron-beam energy as laser energy when the laser is operated as an amplifier. The experiment is presently being reconfigured to examine its performance as a laser oscillator.

Boyer, K.; Baru, C.A.; Newnam, B.E.; Stein, W.E.; Warren, R.W.; Winston, J.G.; Young, L.M.

1983-01-01T23:59:59.000Z

272

Catalyst regeneration apparatus with radial flow distribution  

Science Conference Proceedings (OSTI)

Apparatus is described for regenerating spent hydrocarbon conversion catalyst. Catalyst particles in a vertically-elongated movable tapered bed are contacted with a hot oxygen-containing gas stream in order to remove, by means of combustion, coke which accumulated on the catalyst particles while they were used in a hydrocarbon conversion zone. Catalyst moves downward under the influence of gravity. The catalyst bed is tapered such that the thickness of the bed, in a dimension which is transverse to the direction of catalyst movement, varies from a minimum at the top of the tapered bed to a maximum at the bottom of the tapered bed. Gas passes through the tapered bed in a direction which is substantially transverse to the direction of catalyst movement. Substantially, all of the catalyst in the bed is in contact with the flowing gas. The variation in bed thickness causes a varying gas flow rate through the bed, from a maximum flow rate at the top of the tapered bed to a minimum flow rate at the bottom of the tapered bed and reduces the time that catalyst is exposed to high temperature gases. This flow pattern results in the delivery of oxygen in a manner which more closely matches the oxygen requirement for combustion at each point in the tapered bed. Advantages of the invention include increased coke burning capacity and longer catalyst life. Catalytic reforming is an example of a hydrocarbon conversion process in which the invention may be advantageously employed. 9 figs.

Sechrist, P.A.; Koves, W.J.

1994-01-11T23:59:59.000Z

273

Quantum Dot Solar Cells: High Efficiency through Multiple Exciton Generation  

DOE Green Energy (OSTI)

Impact ionization is a process in which absorbed photons in semiconductors that are at least twice the bandgap can produce multiple electron-hole pairs. For single-bandgap photovoltaic devices, this effect produces greatly enhanced theoretical thermodynamic conversion efficiencies that range from 45-85%, depending upon solar concentration, the cell temperature, and the number of electron-hole pairs produced per photon. For quantum dots (QDs), electron-hole pairs exist as excitons. We have observed astoundingly efficient multiple exciton generation (MEG) in QDs of PbSe (bulk Eg = 0.28 eV), ranging in diameter from 3.9 to 5.7nm (Eg = 0.73, 0.82, and 0.91 eV, respectively). The effective masses of electron and holes are about equal in PbSe, and the onset for efficient MEG occurs at about three times the QD HOMO-LUMO transition (its ''bandgap''). The quantum yield rises quickly after the onset and reaches 300% at 4 x Eg (3.64 eV) for the smallest QD; this means that every QD in the sample produces three electron-hole pairs/photon.

Hanna, M. C.; Ellingson, R. J.; Beard, M.; Yu, P.; Micic, O. I.; Nozik, A. J.; c.

2005-01-01T23:59:59.000Z

274

High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency  

SciTech Connect

This document presents a road map for improving the energy efficiency of hospitals and other healthcare facilities. The report compiles input from a broad array of experts in healthcare facility design and operations. The initial section lists challenges and barriers to efficiency improvements in healthcare. Opportunities are organized around the following ten themes: understanding and benchmarking energy use; best practices and training; codes and standards; improved utilization of existing HVAC designs and technology; innovation in HVAC design and technology; electrical system design; lighting; medical equipment and process loads; economic and organizational issues; and the design of next generation sustainable hospitals. Achieving energy efficiency will require a broad set of activities including research, development, deployment, demonstration, training, etc., organized around 48 specific objectives. Specific activities are prioritized in consideration of potential impact, likelihood of near- or mid-term feasibility and anticipated cost-effectiveness. This document is intended to be broad in consideration though not exhaustive. Opportunities and needs are identified and described with the goal of focusing efforts and resources.

Singer, Brett C.; Tschudi, William F.

2009-09-08T23:59:59.000Z

275

Alloy Design of 9% Cr Steel for High Efficiency Ultra-Supercritical ...  

Science Conference Proceedings (OSTI)

Presentation Title, Alloy Design of 9% Cr Steel for High Efficiency Ultra- Supercritical Power Plants. Author(s), Fujio Abe. On-Site Speaker (Planned), Fujio Abe.

276

Design and global optimization of high-efficiency solar thermal systems with tungsten cermets  

E-Print Network (OSTI)

Solar thermal, thermoelectric, and thermophotovoltaic (TPV) systems have high maximum theoretical efficiencies; experimental systems fall short because of losses by selective solar absorbers and TPV selective emitters. To ...

Chester, David A.

277

Scientists Confirm Robustness of Key Component in Ultra-High-Efficiency Solar Cell (Fact Sheet)  

DOE Green Energy (OSTI)

Scientists developed and tested a new, stable 1-eV metamorphic junction for a high efficiency multijunction III-V solar cell for CPV application.

Not Available

2011-05-01T23:59:59.000Z

278

High-Efficiency Solar Cells for Large-Scale Electricity Generation  

DOE Green Energy (OSTI)

One strategy for helping the solar industry to grow faster is to use very high efficiency cells under concentrating optics. By using lenses or mirrors to concentrate the light, very small solar cells can be used, reducing the amount of semiconductor material and allowing use of higher efficiency cells, which are now >40% efficient.

Kurtz, S.; Olson, J.; Geisz, J.; Friedman, D.; McMahon, W.; Ptak, A.; Wanlass, M.; Kibbler, A.; Kramer, C.; Bertness, K.; Ward, S.; Duda, A.; Young, M.; Carapella, J.; Steiner, M.

2008-09-26T23:59:59.000Z

279

Enhancement of alkylation catalysts for improved supercritical fluid regeneration  

DOE Patents (OSTI)

A method of modifying an alkylation catalyst to reduce the formation of condensed hydrocarbon species thereon. The method comprises providing an alkylation catalyst comprising a plurality of active sites. The plurality of active sites on the alkylation catalyst may include a plurality of weakly acidic active sites, intermediate acidity active sites, and strongly acidic active sites. A base is adsorbed to a portion of the plurality of active sites, such as the strongly acidic active sites, selectively poisoning the strongly acidic active sites. A method of modifying the alkylation catalyst by providing an alkylation catalyst comprising a pore size distribution that sterically constrains formation of the condensed hydrocarbon species on the alkylation catalyst or by synthesizing the alkylation catalyst to comprise a decreased number of strongly acidic active sites is also disclosed, as is a method of improving a regeneration efficiency of the alkylation catalyst.

Ginosar, Daniel M. (Idaho Falls, ID); Petkovic, Lucia M. (Idaho Falls, ID)

2010-12-28T23:59:59.000Z

280

Enhancement of alkylation catalysts for improved supercritical fluid regeneration  

DOE Patents (OSTI)

A method of modifying an alkylation catalyst to reduce the formation of condensed hydrocarbon species thereon. The method comprises providing an alkylation catalyst comprising a plurality of active sites. The plurality of active sites on the alkylation catalyst may include a plurality of weakly acidic active sites, intermediate acidity active sites, and strongly acidic active sites. A base is adsorbed to a portion of the plurality of active sites, such as the strongly acidic active sites, selectively poisoning the strongly acidic active sites. A method of modifying the alkylation catalyst by providing an alkylation catalyst comprising a pore size distribution that sterically constrains formation of the condensed hydrocarbon species on the alkylation catalyst or by synthesizing the alkylation catalyst to comprise a decreased number of strongly acidic active sites is also disclosed, as is a method of improving a regeneration efficiency of the alkylation catalyst.

Ginosar, Daniel M. (Idaho Falls, ID); Petkovic, Lucia (Idaho Falls, ID)

2009-09-22T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Highly efficient photochemical HCOOH production from CO{sub 2} and water using an inorganic system  

SciTech Connect

We have constructed a system that uses solar energy to react CO{sub 2} with water to generate formic acid (HCOOH) at an energy conversion efficiency of 0.15%. It consists of an AlGaN/GaN anode photoelectrode and indium (In) cathode that are electrically connected outside of the reactor cell. High energy conversion efficiency is realized due to a high quantum efficiency of 28% at 300 nm, attributable to efficient electron-hole separation in the semiconductor's heterostructure. The efficiency is close to that of natural photosynthesis in plants, and what is more, the reaction product (HCOOH) can be used as a renewable energy source.

Yotsuhashi, Satoshi; Hashiba, Hiroshi; Deguchi, Masahiro; Zenitani, Yuji; Hinogami, Reiko; Yamada, Yuka [Advanced Technology Research Laboratory, Panasonic Corporation, Soraku-gun, Kyoto 619-0237 (Japan); Deura, Momoko; Ohkawa, Kazuhiro [Department of Applied Physics, Tokyo University of Science, Shinjuku, Tokyo 162-8601 (Japan)

2012-12-15T23:59:59.000Z

282

Current-matched high-efficiency, multijunction monolithic solar cells  

DOE Patents (OSTI)

The efficiency of a two-junction (cascade) tandem photovoltaic device is improved by adjusting (decreasing) the top cell thickness to achieve current matching. An example of the invention was fabricated out of Ga.sub.0.52 In.sub.0.48 P and GaAs. Additional lattice-matched systems to which the invention pertains include Al.sub.x Ga.sub.1-x /GaAS (x= 0.3-0.4), GaAs/Ge and Ga.sub.y In.sub.l-y P/Ga.sub.y+0.5 In.sub.0.5-y As (0

Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)

1993-01-01T23:59:59.000Z

283

High efficiency fuel cell/advanced turbine power cycles  

Science Conference Proceedings (OSTI)

The following figures are included: Westinghouse (W.) SOFC pilot manufacturing facility; cell scale-up plan; W. 25 kW SOFC unit at the utility`s facility on Rokko Island; pressure effect on SOFC power and efficiency; SureCELL{trademark} vs conventional gas turbine plants; SureCELL{trademark} product line for distributed power applications; 20 MW pressurized SOFC/gas turbine power plant; 10 MW SOFT/CT power plant; SureCELL{trademark} plant concept design requirements; and W. SOFC market entry.

Morehead, H.

1996-12-31T23:59:59.000Z

284

High-efficiency solar cells using HEM silicon  

DOE Green Energy (OSTI)

Developments in Heat Exchanger Method (HEM) technology for production of multicrystalline silicon ingot production have led to growth of larger ingots (55 cm square cross section) with lower costs and reliability in production. A single reusable crucible has been used to produce 18 multicrystalline 33 cm square cross section 40 kg ingots, and capability to produce 44 cm ingots has been demonstrated. Large area solar cells of 16.3% (42 cm{sup 2}) and 15.3% (100 cm{sup 2}) efficiency have been produced without optimization of the material production and the solar cell processing.

Khattak, C.P.; Schmid, F. [Crystal Systems, Inc., Salem, MA (United States); Schubert, W.K. [Sandia National Labs., Albuquerque, NM (United States)

1994-12-31T23:59:59.000Z

285

High Efficiency Gas Turbines Overcome Cogeneration Project Feasibility Hurdles  

E-Print Network (OSTI)

Cogeneration project feasibility sometimes fails during early planning stages due to an electrical cycle efficiency which could be improved through the use of aeroderivative gas turbine engines. The aeroderivative engine offers greater degrees of freedom in terms of power augmentation through steam injection, NOx control without selective catalytic reduction, (SCR), reduced down time during maintenance and dispatchability. Other factors influencing enhanced aeroderivative economics are complete generator set packaging at the factory and full string testing before the delivery. A wide variety of hosts, including institutions, utilities, municipalities and industrial factories are observing that their cogeneration projects move faster by implementing aeroderivative gas turbine generation packages.

King, J.

1988-09-01T23:59:59.000Z

286

Efficient CO2 Fixation Pathways: Energy Plant: High Efficiency Photosynthetic Organisms  

SciTech Connect

PETRO Project: UCLA is redesigning the carbon fixation pathways of plants to make them more efficient at capturing the energy in sunlight. Carbon fixation is the key process that plants use to convert carbon dioxide (CO2) from the atmosphere into higher energy molecules (such as sugars) using energy from the sun. UCLA is addressing the inefficiency of the process through an alternative biochemical pathway that uses 50% less energy than the pathway used by all land plants. In addition, instead of producing sugars, UCLA’s designer pathway will produce pyruvate, the precursor of choice for a wide variety of liquid fuels. Theoretically, the new biochemical pathway will allow a plant to capture 200% as much CO2 using the same amount of light. The pathways will first be tested on model photosynthetic organisms and later incorporated into other plants, thus dramatically improving the productivity of both food and fuel crops.

None

2012-01-01T23:59:59.000Z

287

Hydrocarbon synthesis catalyst and method of preparation  

DOE Patents (OSTI)

A catalyst for the synthesis of hydrocarbons from carbon monoxide and hydrogen composed of palladium or platinum and cobalt supported on a solid phase is disclosed. The catalyst is prepared by heating a heterogeneous component of the palladium or platinum deposited on the solid support in a solution of cobalt carbonyl or precursors thereof. The catalyst exhibits excellent activity, stability in air, and produces highly desirable product fractions even with dilute gaseous reactants. The catalyst is preferably used in dilute slurry form, which is desirable from a heat transfer standpoint.

Sapienza, Richard S. (Shoreham, NY); Sansone, Michael J. (Summit, NJ); Slegeir, William A. R. (Hampton Bays, NY)

1983-08-02T23:59:59.000Z

288

Catalyst containing oxygen transport membrane  

Science Conference Proceedings (OSTI)

A composite oxygen transport membrane having a dense layer, a porous support layer and an intermediate porous layer located between the dense layer and the porous support layer. Both the dense layer and the intermediate porous layer are formed from an ionic conductive material to conduct oxygen ions and an electrically conductive material to conduct electrons. The porous support layer has a high permeability, high porosity, and a high average pore diameter and the intermediate porous layer has a lower permeability and lower pore diameter than the porous support layer. Catalyst particles selected to promote oxidation of a combustible substance are located in the intermediate porous layer and in the porous support adjacent to the intermediate porous layer. The catalyst particles can be formed by wicking a solution of catalyst precursors through the porous support toward the intermediate porous layer.

Christie, Gervase Maxwell; Wilson, Jamie Robyn; van Hassel, Bart Antonie

2012-12-04T23:59:59.000Z

289

Optimization of high-performance superscalar architectures for energy efficiency  

Science Conference Proceedings (OSTI)

In recent years reducing power has become a critical design goal for high-performance microprocessors. This work attempts to bring the power issue to the earliest phase of high-performance microprocessor development. We propose a methodology for power-optimization ...

V. Zyuban; P. Kogge

2000-08-01T23:59:59.000Z

290

High efficiency coaxial klystron-like relativistic backward wave oscillator with a premodulation cavity  

SciTech Connect

The klystron-like relativistic backward wave oscillator (RBWO) combines the transition radiation with Cerenkov radiation and has demonstrated microwave output of high power and high efficiency. The coaxial slow wave structure device can produce microwave with a lower frequency in a smaller cross section. For the purpose of high efficiency, low frequency, and miniaturization, a coaxial klystron-like RBWO with a premodulation cavity is presented. Particle-in-cell simulations show that a microwave with power of 1.15 GW and frequency of 2.1 GHz is generated with conversion efficiency of 48%, whereas for the device with a reflector, the efficiency is 38%.

Xiao Renzhen; Teng Yan; Chen Changhua; Sun Jun [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

2011-11-15T23:59:59.000Z

291

Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalysts to Poisons from High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures  

DOE Green Energy (OSTI)

In the second and third years, researchers from the University of Kentucky Center for Applied Energy Research (UK-CAER) continued the project by evaluating the sensitivity of a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to a number of different compounds, including KHCO{sub 3}, NaHCO{sub 3}, HCl, HBr, HF, H{sub 2}S, NH{sub 3}, and a combination of H{sub 2}S and NH{sub 3}. Cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts were also subjected to a number of the same compounds in order to evaluate their sensitivities at different concentration levels of added contaminant.

Burton Davis; Gary Jacobs; Wenping Ma; Dennis Sparks; Khalid Azzam; Janet Chakkamadathil Mohandas; Wilson Shafer; Venkat Ramana Rao Pendyala

2011-09-30T23:59:59.000Z

292

Method of depositing a catalyst on a fuel cell electrode  

DOE Patents (OSTI)

Fuel cell electrodes comprising a minimal load of catalyst having maximum catalytic activity and a method of forming such fuel cell electrodes. The method comprises vaporizing a catalyst, preferably platinum, in a vacuum to form a catalyst vapor. A catalytically effective amount of the catalyst vapor is deposited onto a carbon catalyst support on the fuel cell electrode. The electrode preferably is carbon cloth. The method reduces the amount of catalyst needed for a high performance fuel cell electrode to about 0.3 mg/cm.sup.2 or less.

Dearnaley, Geoffrey (San Antonio, TX); Arps, James H. (San Antonio, TX)

2000-01-01T23:59:59.000Z

293

High-efficiency spectral purity filter for EUV lithography  

DOE Patents (OSTI)

An asymmetric-cut multilayer diffracts EUV light. A multilayer cut at an angle has the same properties as a blazed grating, and has been demonstrated to have near-perfect performance. Instead of having to nano-fabricate a grating structure with imperfections no greater than several tens of nanometers, a thick multilayer is grown on a substrate and then cut at an inclined angle using coarse and inexpensive methods. Effective grating periods can be produced this way that are 10 to 100 times smaller than those produced today, and the diffraction efficiency of these asymmetric multilayers is higher than conventional gratings. Besides their ease of manufacture, the use of an asymmetric multilayer as a spectral purity filter does not require that the design of an EUV optical system be modified in any way, unlike the proposed use of blazed gratings for such systems.

Chapman, Henry N. (Livermore, CA)

2006-05-23T23:59:59.000Z

294

Towards a high-efficiency micro-thermophotovoltaic generator  

E-Print Network (OSTI)

Hydrocarbon fuels have such a high energy density that even a relatively inefficient converter of chemical energy into electrical can significantly exceed the energy density of state- of-the-art batteries. This work attempts ...

Walker, Chan (Walker R.)

2010-01-01T23:59:59.000Z

295

High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

June 15, 2013 | Singh * Thermal modeling will be conducted to establish the benefits of using a high thermal conducting graphite foams in conjunction with PCM and to develop a...

296

City of High Point Electric - Residential Energy Efficiency Rebate...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

of High Point. In order to qualify, the heat pump must be between 1 and 5 tons, have a SEER rating of 14 or more, and be installed by an authorizedlicensed electrical or HVAC...

297

Highly Efficient Polymer Light-Emitting Diodes Using Graphene ...  

Science Conference Proceedings (OSTI)

A30: Study on Super Stable All-solid-state Battery at High Temperature · A3: Investigation on Co-combustion Kinetics of Anthracite Coal and Biomass Char by  ...

298

Program on Technology Innovation: Very High Efficiency Photovoltaics Research at IRDEP  

Science Conference Proceedings (OSTI)

This is an interim report on the collaborative activities of Centre National de la Recherche Scientifique (CNRS) and Electricité de France (EDF) R&D to advance the state of high-efficiency photovoltaics (PV). These efforts are principally concerned with basic research to enhance the longer-term prospects of very high-efficiency PV, but they may also produce nearer-term outcomes in the shape of improved conversion efficiency for existing technologies.

2009-03-31T23:59:59.000Z

299

High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells  

E-Print Network (OSTI)

High Excitation Transfer Efficiency from Energy Relay Dyes in Dye-Sensitized Solar Cells Brian E soluble energy relay dyes with high molar extinction coefficients. KEYWORDS Solar cell, energy transfer-sensitized solar cells, the excited ERDs must be able to efficiently transfer energy to the sensitizing dyes

McGehee, Michael

300

Highly-efficient noise-assisted energy transport in classical oscillator systems  

E-Print Network (OSTI)

Photosynthesis is a biological process that involves the highly-efficient transport of energy captured from the sun to a reaction center, where conversion into useful biochemical energy takes place. Even though one can always use a quantum perspective to describe any physical process, since everything follows the laws of Quantum Mechanics, is the use of quantum theory imperative to explain this high efficiency? Several theoretical studies suggest that the high efficiency can only be understood as a result of the interplay between the quantum coherent evolution of the photosynthetic system, and noise introduced by its surrounding environment. Notwithstanding, we show here that noise-assisted highly-efficient energy transport can be found as well in purely classical systems; therefore, we might conclude that high efficiency energy transfer in photosynthetic systems could also be anticipated by classical models, without the need to resorting to quantum effects. Strikingly, the wider scope of applicability of the...

León-Montiel, R de J

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

A high-efficiency indirect lighting system utilizing the solar 1000 sulfur lamp  

SciTech Connect

High-lumen light sources represent unique challenges and opportunities for the design of practical and efficient interior lighting systems. High-output sources require a means of large-scale distribution and avoidance of high-luminance glare while providing efficient delivery. An indirect lighting system has been developed for use with a 1,000 Watt sulfur lamp that efficiently utilizes the high-output source to provide quality interior lighting. This paper briefly describes the design and initial testing of this new system.

Siminovitch, M.; Gould, C.; Page, E.

1997-06-01T23:59:59.000Z

302

Power efficiency for very high temperature solar thermal cavity receivers  

DOE Patents (OSTI)

This invention is an improved solar energy cavity receiver for exposing materials and components to high temperatures. The receiver includes a housing having an internal reflective surface defining a cavity and having an inlet for admitting solar radiation thereto. A photothermal absorber is positioned in the cavity to receive radiation from the inlet. A reflective baffle is positioned between the absorber and the inlet to severely restrict the re-radiation of energy through the inlet. The front surface of the baffle defines a narrow annulus with the internal reflective surface of the housing. The front surface of the baffle is contoured to reflect incoming radiation onto the internal surface of the housing, from which it is reflected through the annulus and onto the front surface of the absorber. The back surface of the baffle intercepts infrared radiation from the front of the absorber. With this arrangement, a high percentage of the solar power input is retained in the cavity; thus, high internal temperatures are attained.

McDougal, Allan R. (LaCanada-Flintridge, CA); Hale, Robert R. (Upland, CA)

1984-01-01T23:59:59.000Z

303

Tungsten Cathode Catalyst for PEMFC  

DOE Green Energy (OSTI)

Final report for project to evaluate tungsten-based catalyst as a cathode catalyst for PEM cell applications.

Joel B. Christian; Sean P. E. Smith

2006-09-22T23:59:59.000Z

304

Glossary Term - Catalyst  

NLE Websites -- All DOE Office Websites (Extended Search)

Bohr Radius Previous Term (Bohr Radius) Glossary Main Index Next Term (Ceres) Ceres Catalyst A catalyst is a substance that increases the speed of a chemical reaction without being...

305

Sensitivity of Fischer-Tropsch Synthesis and Water-Gas Shift Catalysts to Poisons from High-Temperature High-Pressure Entrained-Flow (EF) Oxygen-Blown Gasifier Gasification of Coal/Biomass Mixtures  

DOE Green Energy (OSTI)

The successful adaptation of conventional cobalt and iron-based Fischer-Tropsch synthesis catalysts for use in converting biomass-derived syngas hinges in part on understanding their susceptibility to byproducts produced during the biomass gasification process. With the possibility that oil production will peak in the near future, and due to concerns in maintaining energy security, the conversion of biomass-derived syngas and syngas derived from coal/biomass blends to Fischer-Tropsch synthesis products to liquid fuels may provide a sustainable path forward, especially considering if carbon sequestration can be successfully demonstrated. However, one current drawback is that it is unknown whether conventional catalysts based on iron and cobalt will be suitable without proper development because, while ash, sulfur compounds, traces of metals, halide compounds, and nitrogen-containing chemicals will likely be lower in concentration in syngas derived from mixtures of coal and biomass (i.e., using an entrained-flow oxygen-blown gasifier) than solely from coal, other byproducts may be present in higher concentrations. The current project examines the impact of a number of potential byproducts of concern from the gasification of biomass process, including compounds containing alkali chemicals like the chlorides of sodium and potassium. In the second year, researchers from the University of Kentucky Center for Applied Energy Research (UK-CAER) continued the project by evaluating the sensitivity of a commercial iron-chromia high temperature water-gas shift catalyst (WGS) to a number of different compounds, including KHCO{sub 3}, NaHCO{sub 3}, HCl, HBr, HF, H{sub 2}S, NH{sub 3}, and a combination of H{sub 2}S and NH{sub 3}. Cobalt and iron-based Fischer-Tropsch synthesis (FT) catalysts were also subjected to a number of the same compounds in order to evaluate their sensitivities.

Burtron Davis; Gary Jacobs; Wenping Ma; Khalid Azzam; Dennis Sparks; Wilson Shafer

2010-09-30T23:59:59.000Z

306

New III-V cell design approaches for very high efficiency  

DOE Green Energy (OSTI)

This report describes to examine new solar cell desip approaches for achieving very high conversion efficiencies. The program consists of two elements. The first centers on exploring new thin-film approaches specifically designed for M-III semiconductors. Substantial efficiency gains may be possible by employing light trapping techniques to confine the incident photons, as well as the photons emitted by radiative recombination. The thin-film approach is a promising route for achieving substantial performance improvements in the already high-efficiency, single-junction, III-V cell. The second element of the research involves exploring desip approaches for achieving high conversion efficiencies without requiring extremely high-quality material. This work has applications to multiple-junction cells, for which the selection of a component cell often involves a compromise between optimum band pp and optimum material quality. It could also be a benefit manufacturing environment by making the cell's efficiency less dependent on materialquality.

Lundstrom, M.S.; Melloch, M.R.; Lush, G.B.; Patkar, M.P.; Young, M.P. (Purdue Univ., Lafayette, IN (United States))

1993-04-01T23:59:59.000Z

307

DIRECT DECOMPOSITION OF METHANE TO HYDROGEN ON METAL LOADED ZEOLITE CATALYST  

DOE Green Energy (OSTI)

The manufacture of hydrogen from natural gas is essential for the production of ultra clean transportation fuels. Not only is hydrogen necessary to upgrade low quality crude oils to high-quality, low sulfur ultra clean transportation fuels, hydrogen could eventually replace gasoline and diesel as the ultra clean transportation fuel of the future. Currently, refinery hydrogen is produced through the steam reforming of natural gas. Although efficient, the process is responsible for a significant portion of refinery CO2 emissions. This project is examining the direct catalytic decomposition of methane as an alternative to steam reforming. The energy required to produce one mole of hydrogen is slightly lower and the process does not require water-gas-shift or pressure-swing adsorption units. The decomposition process does not produce CO2 emissions and the product is not contaminated with CO -- a poison for PEM fuel cells. In this work we examined the direct catalytic decomposition of methane over a metal modified zeolite catalyst and the recovery of catalyst activity by calcination. A favorable production of hydrogen was obtained, when compared with previously reported nickel-zeolite supported catalysts. Reaction temperature had a strong influence on catalyst activity and on the type of carbon deposits. The catalyst utilized at 873 and 973 K could be regenerated without any significant loss of activity, however the catalyst utilized at 1073 K showed some loss of activity after regeneration.

Lucia M. Petkovic; Daniel M. Ginosar; Kyle C. Burch; Harry W. Rollins

2005-08-01T23:59:59.000Z

308

Catalyst Management Planning  

Science Conference Proceedings (OSTI)

Catalyst used in selective catalytic reduction (SCR) systems for NOx control in coal-fired power plants is susceptible to deactivation over time due to exposure to trace elements contained in the coal. In order to sustain the levels of NOx reduction needed to comply with regulatory requirements, periodic replacement of the catalyst modules with new or regenerated catalyst is an essential element in operating an SCR system. Catalyst management planning is a process whereby decisions are made about when ca...

2010-12-21T23:59:59.000Z

309

The Science and Engineering of Durable Ultralow PGM Catalysts- 2012 DOE-EERE-FCT annual progress report  

Science Conference Proceedings (OSTI)

Minimizing the quantity of Pt group metals used in polymer membrane fuel cells (PEMFCs) is one of the remaining grand challenges for fuel cell commercialization. Tremendous progress has been achieved over the last two decades in decreasing the Pt loading required for efficient fuel cell performance. Unfortunately, the fluctuations in the price of Pt represent a substantial barrier to the economics of widespread fuel cell use. Durability and impurity tolerance are also challenges that are tightly coupled to fuel cell Pt electrode loading. Traditional approaches to decreasing the amount of Pt required for good performance include: (1) Increasing mass activity by decreasing Pt particle size by supporting on carbon; (2) Alloy formulation Pt-Co, Pt-Cr alloys to improve mass activity; (3) Increasing Pt utilization by optimization of electronic and ionic contact of the Pt particles; (4) Improving conductivity of the electronic and ionic conducting constituents of the membrane electrode assembly; and (5) Improving reactant to and product mass transport away from the electroactive sites. Recent novel approaches include the nanoengineering of core shell catalysts and Pt particles of unusual geometries such as nanowires/whiskers. The success of the aforementioned approaches has been great; however further advances using such approaches have been hampered by a lack of underlining scientific understanding of the catalyst activity, particle growth mechanisms, and optimization strategies for designing composite electrodes The objectives of this report are: (1) Development of durable, high mass activity Platinum Group Metal (PGM) cathode catalysts-enabling lower cost fuel cells; (2) Elucidation of the fundamental relationships between PGM catalyst shape, particle size and activity to help design better catalysts; (3) Optimization of the cathode electrode layer to maximize the performance of PGM catalysts-improving fuel cell performance and lowering cost; (4) Understanding the performance degradation mechanisms of high mass activity cathode catalysts-provide insights to better catalyst design; and (5) Development and testing of fuel cells using ultra-low loading high activity PGM catalysts-validation of advanced concepts.

Garzon, Fernando H. [Los Alamos National Laboratory

2012-07-16T23:59:59.000Z

310

High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

April 15. 2013 | Singh April 15. 2013 | Singh * Thermal modeling will be conducted to establish the benefits of using a high thermal conducting graphite foams in conjunction with PCM and to develop a design for a laboratory scale prototype. * Variety of characterizations will be carried out to qualify the materials (PCMs, alloys, coatings) for the prototype construction. * Process to infiltrate selected PCM into the foam will be developed. * Using the appropriate brazing/joining techniques, prototype will be assembled. * Performance testing of the TES system prototype to ensure a full- scale system will meet the SunShot goals. * Complete cost analysis of the proposed TES system * Complete laboratory scale prototype design * Develop SiC coating using polycarbosilanes for graphite

311

Development of high efficiency collector plates. Final report  

DOE Green Energy (OSTI)

Composite metal technology was used to manufacture intermetallic compound (IC) absorption surfaces and to combine them integrally with composite metal tube-in-sheet collector plates. Five material systems in which Al was one component metal and Fe, Cr, or Ni and their alloy was the other pair, were evaluated. All intermetallic compounds had high solar absorptance ..cap alpha.. approx. = 0.9. The AlNi was most promising and ..cap alpha.. > or = 0.95 and epsilon approx. = 0.3 were obtained over a broad range of compounding conditions. After eight months exposure in a flat plate collector enclosure the characteristic properties of AlNi surfaces remained virtually unchanged. Only LCS/Cu composite metal tube-in-sheet collector plates could be manufactured successfully. The technical difficulties associated with integrating the intermetallic compound and tube-in-sheet technologies make the manufacturing of composite metal collector plates at the time being economically unfeasible.

Santala, T.; Sabol, R.

1976-02-01T23:59:59.000Z

312

New approaches for high-efficiency solar cells. Final report  

DOE Green Energy (OSTI)

This report summarizes the activities carried out in this subcontract. These activities cover, first the atomic layer epitaxy (ALE) growth of GaAs, AlGaAs and InGaP at fairly low growth temperatures. This was followed by using ALE to achieve high levels of doping both n-type and p-type required for tunnel junctions (Tj) in the cascade solar cell structures. Then the authors studied the properties of AlGaAs/InGaP and AlGaAs/GaAs tunnel junctions and their performances at different growth conditions. This is followed by the use of these tunnel junctions in stacked solar cell structures. The effect of these tunnel junctions on the performance of stacked solar cells was studied at different temperatures and different solar fluences. Finally, the authors studied the effect of different types of black surface fields (BSF), both p/n and n/p GaInP solar cell structures, and their potential for window layer applications. Parts of these activities were carried in close cooperation with Dr. Mike Timmons of the Research Triangle Institute.

Bedair, S.M.; El-Masry, N.A. [North Carolina State Univ., Raleigh, NC (United States)

1997-12-01T23:59:59.000Z

313

Kieffer Paper Mill's Recycled Fiber Mill and PSI Energy's High Efficiency Motors Plan  

E-Print Network (OSTI)

The needs of electricity consumers along with the utility industry are rapidly changing. Consumers want electricity to perform more functions, improve efficiencies and help lower the cost of production, all in an environmentally responsible manner. In 1991, PSI Energy developed a comprehensive Demand-Side Management program, called Energy Matters™, aimed at improving the overall end-use efficiency of its customers. Its goal is to reduce summer peak demand 120 megawatts by the summer of 1995. Kieffer Paper Mills in Brownstown, IN had a need to address the efficiency of its new, state-of-the-art pulp processing mill that it was building. With over 4,000 horsepower of process motors going into the new plant, even a modest improvement in motor efficiency would yield significant energy savings. PSI Energy was able to help Kieffer examine the economics of high efficiency motors, and through the PSI Energy High Efficiency Motors Plan encouraged Kieffer Paper Mills to purchase energy efficient motors by helping pay part of the cost differential between high efficiency and standard efficiency models.

Myers, J. A.

1993-03-01T23:59:59.000Z

314

System for reactivating catalysts  

DOE Patents (OSTI)

A method of reactivating a catalyst, such as a solid catalyst or a liquid catalyst is provided. The method comprises providing a catalyst that is at least partially deactivated by fouling agents. The catalyst is contacted with a fluid reactivating agent that is at or above a critical point of the fluid reactivating agent and is of sufficient density to dissolve impurities. The fluid reactivating agent reacts with at least one fouling agent, releasing the at least one fouling agent from the catalyst. The at least one fouling agent becomes dissolved in the fluid reactivating agent and is subsequently separated or removed from the fluid reactivating agent so that the fluid reactivating agent may be reused. A system for reactivating a catalyst is also disclosed.

Ginosar, Daniel M. (Idaho Falls, ID); Thompson, David N. (Idaho Falls, ID); Anderson, Raymond P. (Idaho Falls, ID)

2010-03-02T23:59:59.000Z

315

SunShot Initiative: Development and Productization of High-Efficiency,  

NLE Websites -- All DOE Office Websites (Extended Search)

Development and Productization of Development and Productization of High-Efficiency, Low-Cost Building-Integrated PV Shingles Using Monocrystalline Silicon Thin-Film Solar Cells to someone by E-mail Share SunShot Initiative: Development and Productization of High-Efficiency, Low-Cost Building-Integrated PV Shingles Using Monocrystalline Silicon Thin-Film Solar Cells on Facebook Tweet about SunShot Initiative: Development and Productization of High-Efficiency, Low-Cost Building-Integrated PV Shingles Using Monocrystalline Silicon Thin-Film Solar Cells on Twitter Bookmark SunShot Initiative: Development and Productization of High-Efficiency, Low-Cost Building-Integrated PV Shingles Using Monocrystalline Silicon Thin-Film Solar Cells on Google Bookmark SunShot Initiative: Development and Productization of

316

High efficiency wideband envelope tracking power amplifier for next-generation wireless communications  

E-Print Network (OSTI)

maximum gate-to-source voltage requirements of the switcherthis high supply voltage requirement, 0.35-µm 30 V N-channelvoltage envelope amplifier efficiency of 72%, and the linearity requirements

Kwak, Myoungbo

2011-01-01T23:59:59.000Z

317

Nonlinear Transmission Impairments in High-Spectral Efficiency Fiber-Optic Communications  

E-Print Network (OSTI)

and K. Higuma, "25.6-Tb/s WDM Transmission of Polarization-High-spectral-efficiency transmission systems," in OpticalFujita, "100-Gb/s DQPSK Transmission Experiment Without OTDM

Wang, Yi-Hsiang

2011-01-01T23:59:59.000Z

318

Full-Spectrum Semiconducting Material for Affordable, Highly Efficient Solar Cells  

Wladyslaw Walukiewicz and Kin Man Yu of Berkeley Lab have designed a new semiconducting material that will enable the fabrication of high efficiency solar cells at a fraction of the price of other technologies. 

319

Conversion Tower for Dispatchable Solar Power: High-Efficiency Solar-Electric Conversion Power Tower  

Science Conference Proceedings (OSTI)

HEATS Project: Abengoa Solar is developing a high-efficiency solar-electric conversion tower to enable low-cost, fully dispatchable solar energy generation. Abengoa’s conversion tower utilizes new system architecture and a two-phase thermal energy storage media with an efficient supercritical carbon dioxide (CO2) power cycle. The company is using a high-temperature heat-transfer fluid with a phase change in between its hot and cold operating temperature. The fluid serves as a heat storage material and is cheaper and more efficient than conventional heat-storage materials, like molten salt. It also allows the use of a high heat flux solar receiver, advanced high thermal energy density storage, and more efficient power cycles.

None

2012-01-11T23:59:59.000Z

320

High-efficiency second-harmonic generation in doubly-resonant ?[superscript (2)] microring resonators  

E-Print Network (OSTI)

By directly simulating Maxwell’s equations via the finite-difference time-domain (FDTD) method, we numerically demonstrate the possibility of achieving high-efficiency second harmonic generation (SHG) in a structure ...

Bi, Zhuan-Fang

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

High efficiency resonant dc/dc converter for solar power applications  

E-Print Network (OSTI)

This thesis presents a new topology for a high efficiency dc/dc resonant power converter that utilizes a resistance compression network to provide simultaneous zero voltage switching and near zero current switching across ...

Inam, Wardah

2013-01-01T23:59:59.000Z

322

High-Efficiency 6?? Multicrystalline Black Solar Cells Based on Metal-Nanoparticle-Assisted Chemical Etching  

E-Print Network (OSTI)

Multicrystalline silicon (mc-Si) photovoltaic (PV) solar cells with nanoscale surface texturing by metal-nanoparticle-assisted etching are proposed to achieve high power efficiency. The investigation of average nanorod ...

Hsu, W. Chuck

2012-01-01T23:59:59.000Z

323

Process for magnetic beneficiating petroleum cracking catalyst  

DOE Patents (OSTI)

A process for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded.

Doctor, Richard D. (Lisle, IL)

1993-01-01T23:59:59.000Z

324

Process for magnetic beneficiating petroleum cracking catalyst  

DOE Patents (OSTI)

A process is described for beneficiating a particulate zeolite petroleum cracking catalyst having metal values in excess of 1000 ppm nickel equivalents. The particulate catalyst is passed through a magnetic field in the range of from about 2 Tesla to about 5 Tesla generated by a superconducting quadrupole open-gradient magnetic system for a time sufficient to effect separation of said catalyst into a plurality of zones having different nickel equivalent concentrations. A first zone has nickel equivalents of about 6,000 ppm and greater, a second zone has nickel equivalents in the range of from about 2000 ppm to about 6000 ppm, and a third zone has nickel equivalents of about 2000 ppm and less. The zones of catalyst are separated and the second zone material is recycled to a fluidized bed of zeolite petroleum cracking catalyst. The low nickel equivalent zone is treated while the high nickel equivalent zone is discarded. 1 figures.

Doctor, R.D.

1993-10-05T23:59:59.000Z

325

An efficient fixed-point IMDCT algorithm for high-resolution audio appliances  

Science Conference Proceedings (OSTI)

In this paper, we propose an efficient fixed-point IMDCT algorithm for high-resolution audio (or audio/video) appliances such as digital media receiver (DMR) and high-end portable media player (PMP). A novel block floating-point algorithm and a method ... Keywords: High-resolution audio, IMDCT, block floating-point, guard bits

Byoung Eul Kim; Jin-Yong Chung; Sun-Young Hwang

2008-11-01T23:59:59.000Z

326

Membrane catalyst layer for fuel cells  

DOE Patents (OSTI)

A gas reaction fuel cell incorporates a thin catalyst layer between a solid polymer electrolyte (SPE) membrane and a porous electrode backing. The catalyst layer is preferably less than about 10 .mu.m in thickness with a carbon supported platinum catalyst loading less than about 0.35 mgPt/cm.sup.2. The film is formed as an ink that is spread and cured on a film release blank. The cured film is then transferred to the SPE membrane and hot pressed into the surface to form a catalyst layer having a controlled thickness and catalyst distribution. Alternatively, the catalyst layer is formed by applying a Na.sup.+ form of a perfluorosulfonate ionomer directly to the membrane, drying the film at a high temperature, and then converting the film back to the protonated form of the ionomer. The layer has adequate gas permeability so that cell performance is not affected and has a density and particle distribution effective to optimize proton access to the catalyst and electronic continuity for electron flow from the half-cell reaction occurring at the catalyst.

Wilson, Mahlon S. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

327

Pf/Zeolite Catalyst for Tritium Stripping  

DOE Green Energy (OSTI)

This report described promising hydrogen (protium and tritium) stripping results obtained with a Pd/zeolite catalyst at ambient temperature. Preliminary results show 90-99+ percent tritium stripping efficiency may be obtained, with even better performance expected as bed configuration and operating conditions are optimized. These results suggest that portable units with single beds of the Pd/zeolite catalyst may be utilized as ''catalytic absorbers'' to clean up both tritium gas and tritiated water. A cart-mounted prototype stripper utilizing this catalyst has been constructed for testing. This portable stripper has potential applications in maintenance-type jobs such as tritium line breaks. This catalyst can also potentially be utilized in an emergency stripper for the Replacement Tritium Facility.

Hsu, R.H.

2001-03-26T23:59:59.000Z

328

Distillation: Energy Savings and Other Benefits From the Use of High Efficiency Packings  

E-Print Network (OSTI)

A great deal of attention has been focused lately on the use of high-efficiency packings for distillation applications. This paper discusses benefits that can be derived from the use of these devices. In particular, the reduction in energy requirements for a given separation is addressed for both new and retrofit applications. Pressure loss and product decomposition are also considered, and the basis for an alternative analysis is established. An example is shown in which an existing distillation tray column is retrofitted with a high-efficiency packing. The process advantages achieved, including energy savings, are discussed, as well as the factors governing the selection of the packing. The current limitations on design models for high-efficiency packings with respect to mass transfer efficiency, pressure drop, and capacity in distillation are mentioned briefly. Finally, the applications of these devices to alternative technologies such as liquid-liquid extraction are discussed.

Bravo, J. L.; Fair, J. R.; Humphrey, J. L.

1985-05-01T23:59:59.000Z

329

Opening New Avenues for High-Efficiency, Low-Emission Coal Gasification |  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Opening New Avenues for High-Efficiency, Low-Emission Coal Opening New Avenues for High-Efficiency, Low-Emission Coal Gasification Opening New Avenues for High-Efficiency, Low-Emission Coal Gasification April 10, 2012 - 1:00pm Addthis A rendering of the Pratt & Whitney Rocketdyne high pressure, dry-solids feed pump. A rendering of the Pratt & Whitney Rocketdyne high pressure, dry-solids feed pump. Washington, DC - Gasification. It's a versatile technology that uses coal to produce power, chemicals, and fuels. Inherently low in air emissions, solid byproducts, and wastewater, commercial gasification plants have proven capable of exceeding the most stringent regulations for air- and solids-emissions. However, capital and operational costs have prohibited the widespread adoption of gasification, especially for power

330

High Efficiency, Low Cost Solar Cells Manufactured Using 'Silicon Ink' on Thin Crystalline Silicon Wafers  

DOE Green Energy (OSTI)

Reported are the development and demonstration of a 17% efficient 25mm x 25mm crystalline Silicon solar cell and a 16% efficient 125mm x 125mm crystalline Silicon solar cell, both produced by Ink-jet printing Silicon Ink on a thin crystalline Silicon wafer. To achieve these objectives, processing approaches were developed to print the Silicon Ink in a predetermined pattern to form a high efficiency selective emitter, remove the solvents in the Silicon Ink and fuse the deposited particle Silicon films. Additionally, standard solar cell manufacturing equipment with slightly modified processes were used to complete the fabrication of the Silicon Ink high efficiency solar cells. Also reported are the development and demonstration of a 18.5% efficient 125mm x 125mm monocrystalline Silicon cell, and a 17% efficient 125mm x 125mm multicrystalline Silicon cell, by utilizing high throughput Ink-jet and screen printing technologies. To achieve these objectives, Innovalight developed new high throughput processing tools to print and fuse both p and n type particle Silicon Inks in a predetermined pat-tern applied either on the front or the back of the cell. Additionally, a customized Ink-jet and screen printing systems, coupled with customized substrate handling solution, customized printing algorithms, and a customized ink drying process, in combination with a purchased turn-key line, were used to complete the high efficiency solar cells. This development work delivered a process capable of high volume producing 18.5% efficient crystalline Silicon solar cells and enabled the Innovalight to commercialize its technology by the summer of 2010.

Antoniadis, H.

2011-03-01T23:59:59.000Z

331

Research on stable, high-efficiency, large-area amorphous silicon based modules -- Task B  

DOE Green Energy (OSTI)

This report documents progress in developing a stable, high- efficiency, four-terminal hybrid tandem module. The module consists of a semi-transparent, thin-film silicon:hydrogen alloy (TFS) top circuit and a copper indium diselenide (CuInSe{sub 2}) bottom circuit. Film deposition and patterning processes were successfully extended to 0.4-m{sup 2} substrates. A 33.2-W (8.4% efficient) module with a 3970-cm{sup 2} aperture area and a white back reflector was demonstrated; without the back reflector, the module produced 30.2 W (7.6% efficient). Placing a laminated, 31.6-W, 8.1%-efficient CuInSe{sub 2} module underneath this TFS module, with an air gap between the two, produces 11.2 W (2.9% efficient) over a 3883-cm{sup 2} aperture area. Therefore, the four-terminal tandem power output is 41.4 W, translating to a 10.5% aperture-area efficiency. Subsequently, a 37.8-W (9.7% aperture-area efficiency) CuInSe{sub 2} module was demonstrated with a 3905-cm{sup 2} aperture area. Future performances of single-junction and tandem modules of this size were modeled, and predicted power outputs exceed 50 W (13% efficient) for CuInSe{sub 2} and 65 W (17% efficient) for TFS/CuInSe{sub 2} tandem modules.

Mitchell, K.W.; Willet, D.R. (Siemens Solar Industries, Camarillo, CA (USA))

1990-10-01T23:59:59.000Z

332

Methods of making textured catalysts  

SciTech Connect

A textured catalyst having a hydrothermally-stable support, a metal oxide and a catalyst component is described. Methods of conducting aqueous phase reactions that are catalyzed by a textured catalyst are also described. The invention also provides methods of making textured catalysts and methods of making chemical products using a textured catalyst.

Werpy, Todd (West Richland, WA); Frye, Jr., John G. (Richland, WA); Wang, Yong (Richland, WA); Zacher, Alan H. (Kennewick, WA)

2010-08-17T23:59:59.000Z

333

Development of a Desulfurization Strategy for a NOx Adsorber Catalyst  

DOE Green Energy (OSTI)

Improve NOx regeneration calibration developed in DECSE Phase I project to understand full potential of NOx adsorber catalyst over a range of operating temperatures. Develop and demonstrate a desulfurization process to restore NOx conversion efficiency lost to sulfur contamination. Investigate effect of desulfurization process on long-term performance of the NOx adsorber catalyst.

Tomazic, Dean

2000-08-20T23:59:59.000Z

334

New III-V cell design approaches for very high efficiency  

DOE Green Energy (OSTI)

This report describes progress during the first year of a three-year project. The objective of the research is to examine new design approaches for achieving very high conversion efficiencies. The program is divided into two areas. The first centers on exploring new thin-film approaches specifically designed for III-V semiconductors. The second area centers on exploring design approaches for achieving high conversion efficiencies without requiring extremely high quality material. Research activities consisted of an experimental study of minority carrier recombination in n-type, metal-organic chemical vapor deposition (MOCVD)-deposited GaAs, an assessment of the minority carrier lifetimes in n-GaAs grown by molecular beam epitaxy, and developing a high-efficiency cell fabrication process.

Lundstrom, M.S.; Melloch, M.R.; Lush, G.B.; O'Bradovich, G.J.; Young, M.P. (Purdue Univ., Lafayette, IN (United States))

1993-01-01T23:59:59.000Z

335

Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems  

SciTech Connect

This document summarizes progress on Cooperative Agreement DE-FC26-04NT41992, ''Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems'', during the time-period January 1 through March 31, 2006. The objective of this project is to demonstrate at pilot scale the use of solid honeycomb catalysts to promote the oxidation of elemental mercury in flue gas from coal combustion, and the use of a wet flue gas desulfurization (FGD) system downstream to remove the oxidized mercury at high efficiency. The project is being co-funded by the U.S. DOE National Energy Technology Laboratory, EPRI, Great River Energy (GRE), TXU Generation Company LP, the Southern Company, and Duke Energy. URS Group is the prime contractor. The mercury control process under development uses honeycomb catalysts to promote the oxidation of elemental mercury in the flue gas from coal-fired power plants that have wet lime or limestone FGD systems. Oxidized mercury is removed in the wet FGD absorbers and leaves with the byproducts from the FGD system. The current project is testing previously identified catalyst materials at pilot scale and in a commercial form to provide engineering data for future full-scale designs. The pilot-scale tests will continue for approximately 14 months or longer at each of two sites to provide longer-term catalyst life data. Pilot-scale wet FGD tests are being conducted periodically at each site to confirm the ability to scrub the catalytically oxidized mercury at high efficiency. This is the ninth reporting period for the subject Cooperative Agreement. During this period, project efforts primarily consisted of operating the catalyst pilot units at the TXU Generation Company LP's Monticello Steam Electric Station and at Georgia Power's Plant Yates. Two catalyst activity measurement trips were made to Plant Yates during the quarter. This Technical Progress Report presents catalyst activity results from the oxidation catalyst pilot unit at Plant Yates and discusses the status of the pilot unit at Monticello.

Gary M. Blythe

2006-03-31T23:59:59.000Z

336

Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems  

SciTech Connect

This document summarizes progress on Cooperative Agreement DE-FC26-04NT41992, ''Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems'', during the time-period January 1 through March 31, 2006. The objective of this project is to demonstrate at pilot scale the use of solid honeycomb catalysts to promote the oxidation of elemental mercury in flue gas from coal combustion, and the use of a wet flue gas desulfurization (FGD) system downstream to remove the oxidized mercury at high efficiency. The project is being co-funded by the U.S. DOE National Energy Technology Laboratory, EPRI, Great River Energy (GRE), TXU Generation Company LP, the Southern Company, and Duke Energy. URS Group is the prime contractor. The mercury control process under development uses honeycomb catalysts to promote the oxidation of elemental mercury in the flue gas from coal-fired power plants that have wet lime or limestone FGD systems. Oxidized mercury is removed in the wet FGD absorbers and leaves with the byproducts from the FGD system. The current project is testing previously identified catalyst materials at pilot scale and in a commercial form to provide engineering data for future full-scale designs. The pilot-scale tests will continue for approximately 14 months or longer at each of two sites to provide longer-term catalyst life data. Pilot-scale wet FGD tests are being conducted periodically at each site to confirm the ability to scrub the catalytically oxidized mercury at high efficiency. This is the ninth reporting period for the subject Cooperative Agreement. During this period, project efforts primarily consisted of operating the catalyst pilot units at the TXU Generation Company LP's Monticello Steam Electric Station and at Georgia Power's Plant Yates. Two catalyst activity measurement trips were made to Plant Yates during the quarter. This Technical Progress Report presents catalyst activity results from the oxidation catalyst pilot unit at Plant Yates and discusses the status of the pilot unit at Monticello.

Gary M. Blythe

2006-03-31T23:59:59.000Z

337

METHOD OF PURIFYING CATALYSTS  

DOE Patents (OSTI)

It has been fuund that the presence of chlorine as an impurity adversely affects the performance of finely divided platinum catalysts such as are used in the isotopic exchange process for the production of beavy water. This chlorine impurity may be removed from these catalysts by treating the catalyst at an elevated temperature with dry hydrogen and then with wet hydrogen, having a hydrogen-water vapor volume of about 8: 1. This alternate treatment by dry hydrogen and wet hydrogen is continued until the chlorine is largely removed from the catalyst.

Joris, G.G.

1958-09-01T23:59:59.000Z

338

The Importance of Domain Size and Purity in High-Efficiency Organic Solar  

NLE Websites -- All DOE Office Websites (Extended Search)

The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy (interfaces are everywhere) but the charges' journey as precarious (interfaces are everywhere). Instead, using a combination of x-ray scattering and microscopy techniques, researchers have found that excitons may actually not fare so well in mixed domains but need access to pure aggregates to efficiently convert into charges. The smaller the aggregates, the better, allowing increased interfacial area and dramatic increases in device performance.

339

The Importance of Domain Size and Purity in High-Efficiency Organic Solar  

NLE Websites -- All DOE Office Websites (Extended Search)

The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy (interfaces are everywhere) but the charges' journey as precarious (interfaces are everywhere). Instead, using a combination of x-ray scattering and microscopy techniques, researchers have found that excitons may actually not fare so well in mixed domains but need access to pure aggregates to efficiently convert into charges. The smaller the aggregates, the better, allowing increased interfacial area and dramatic increases in device performance.

340

Developing a Highly Efficient Multi-use Special Economic Zone in India  

NLE Websites -- All DOE Office Websites (Extended Search)

Developing a Highly Efficient Multi-use Special Economic Zone in India Developing a Highly Efficient Multi-use Special Economic Zone in India Speaker(s): Jagadeesh Taluri Kushboo Modgil Date: June 3, 2010 - 12:00pm Location: 90-3122 LBNL is collaborating with Metro Valley to create the most energy efficient built environment in India. The proposed project is an ITES (Information Technology Enabled Services) Special Economic Zone which is a multi-tenanted campus consisting of work and support spaces for companies involved in research or knowledge processing. The goal of the project reaches beyond an energy efficient built environment for the Knowledge Industry to sustainability in the broadest sense: a sustainable environment, not just from the point of view of energy consumption, but also relative to the people who use it, the organizations that inhabit it,

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341

Highly-Efficient Thermoelectronic Conversion of Solar Energy and Heat into Electric Power  

E-Print Network (OSTI)

Electric power may, in principle, be generated in a highly efficient manner from heat created by focused solar irradiation, chemical combustion, or nuclear decay by means of thermionic energy conversion. As the conversion efficiency of the thermionic process tends to be degraded by electron space charges, the efficiencies of thermionic generators have amounted to only a fraction of those fundamentally possible. We show that this space-charge problem can be resolved by shaping the electric potential distribution of the converter such that the static electron space-charge clouds are transformed into an output current. Although the technical development of practical generators will require further substantial efforts, we conclude that a highly efficient transformation of heat to electric power may well be achieved.

Meir, S; Geballe, T H; Mannhart, J

2013-01-01T23:59:59.000Z

342

Time-domain approach to energy efficiency in high-performance network element design  

E-Print Network (OSTI)

Energy efficiency is a corner stone of sustainability in data center and high-performance networking. However, at present there is a notable structural mismatch between network silicon development targets and network equipment utilization patterns in the field. In particular, some aspects of network energy utilization (eg load-proportional energy consumption) routinely stay out of focus during system design and implementation. Drawing from hands-on research and development in high-speed and grid networking, we identify a novel approach to energy efficiency in network engineering. In this paper, we demonstrate how the problem of efficient network system design can be dissected into smaller sections based on timescales of traffic processing. The newly proposed approach allows R&D efforts to be tightly paired to resources and sustainability targets to improve energy efficiency in many classes of network and telecom devices.

Kharitonov, Daniel

2009-01-01T23:59:59.000Z

343

The Importance of Domain Size and Purity in High-Efficiency Organic Solar  

NLE Websites -- All DOE Office Websites (Extended Search)

The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy (interfaces are everywhere) but the charges' journey as precarious (interfaces are everywhere). Instead, using a combination of x-ray scattering and microscopy techniques, researchers have found that excitons may actually not fare so well in mixed domains but need access to pure aggregates to efficiently convert into charges. The smaller the aggregates, the better, allowing increased interfacial area and dramatic increases in device performance.

344

Highly efficient coupling of photons from nanoemitters into single-mode optical fibers  

E-Print Network (OSTI)

Highly efficient coupling of photons from nanoemitters into single-mode optical fibers is demonstrated using tapered fibers. 7.4 +/- 1.2 % of the total emitted photons from single CdSe/ZnS nanocrystals were coupled into a 300-nm-diameter tapered fiber. The dependence of the coupling efficiency on the taper diameter was investigated and the coupling efficiency was found to increase exponentially with decreasing diameter. This method is very promising for nanoparticle sensing and single-photon sources.

Masazumi Fujiwara; Kiyota Toubaru; Tetsuya Noda; Hong-Quan Zhao; Shigeki Takeuchi

2012-09-12T23:59:59.000Z

345

Program on Technology Innovation: High- Efficiency Photovoltaic Research at IRDEP, 2011  

Science Conference Proceedings (OSTI)

 This report describes the advances of the High-Efficiency Photovoltaic (HEPV) program during 2011. The report focuses on the technical advances in the "up-conversion" program, addressing compounds with improved PV energy-conversion potential. Up-conversion uses materials with special optical properties to convert infrared light that cannot be used by standard PV cells into visible light that the cells can efficiently convert to electricity. Results of experiments on up-conversion ...

2012-08-24T23:59:59.000Z

346

ENGINEERED ELECTRODES AND ELECTRODE-ORGANIC INTERFACES FOR HIGH-EFFICIENCY ORGANIC PHOTOVOLTAICS  

DOE Green Energy (OSTI)

Organic photovoltaic (OPV) cells offer the ultimate promise of low cost, readily manufacturable, and durable solar power. While recent advances have led to cells with impressive performance levels, OPV cells have yet to break the double-digit efficiency barrier. Further gains in efficiency and durability, to that competitive with high-performance inorganic photovoltaics will require breakthroughs in transparent electrode and interfacial materials science and engineering. This project involved an integrated basic research effort carried out by an experienced and highly collaborative interdisciplinary team to address in unconventional ways, critical electrode-interfacial issues underlying OPV performance--controlling band offsets between transparent electrodes and organics, addressing current loss/leakage problems at interfaces, enhancing adhesion, interfacial stability, and device durability while minimizing cost. It synergistically combined materials and interfacial reagent synthesis, nanostructural and photovoltaic characterization, and high level quantum theory. The research foci were: 1) understanding of/development of superior transparent electrode materials and materials morphologies--i.e., better matched electronically and chemically to organic active layers, 2) understanding-based development of inorganic interfacial current-collecting/charge-blocking layers, and 3) understanding-based development of self-assembled adhesion/current-collecting/charge-blocking/cross-linking layers for high-efficiency OPV interfaces. Pursing the goal of developing the fundamental scientific understanding needed to design, fabricate, prototype and ultimately test high-efficiency OPV cells incorporating these new concepts, we achieved a record power conversion efficiency of 5.2% for an organic bulk-heterjunction solar cell.

Tobin J. Marks; R.P.H. Chang; Tom Mason; Ken Poeppelmeier; Arthur J. Freeman

2008-11-13T23:59:59.000Z

347

Diesel Emission Control-- Sulfur Effects (DECSE) Program-- Phase II Summary Report: NOx Adsorber Catalysts  

DOE Green Energy (OSTI)

The investigations performed in this project demonstrated the ability to develop a NO{sub x} regeneration strategy including both an improved lean/rich modulation cycle and rich engine calibration, which resulted in a high NO{sub x} conversion efficiency over a range of operating temperatures. A high-temperature cycle was developed to desulfurize the NO{sub x} absorber catalyst. The effectiveness of the desulfurization process was demonstrated on catalysts aged using two different sulfur level fuels. The major findings of this project are as follows: (1) The improved lean/rich engine calibration achieved as a part of this test project resulted in NO{sub x} conversion efficiencies exceeding 90% over a catalyst inlet operating temperature window of 300 C-450 C. This performance level was achieved while staying within the 4% fuel economy penalty target defined for the regeneration calibration. (2) The desulfurization procedure developed showed that six catalysts, which had been exposed to fuel sulfur levels of 3-, 16-, and 30-ppm for as long as 250 hours, could be recovered to greater than 85% NO{sub x} conversion efficiency over a catalyst inlet operating temperature window of 300 C-450 C, after a single desulfurization event. This performance level was achieved while staying within the 4% fuel economy penalty target defined for the regeneration calibration. (3) The desulfurization procedure developed has the potential to meet in-service engine operating conditions and provide acceptable driveability conditions. (4) Although aging with 78-ppm sulfur fuel reduced NO{sub x} conversion efficiency more than aging with 3-ppm sulfur fuel as a result of sulfur contamination, the desulfurization events restored the conversion efficiency to nearly the same level of performance. However, repeatedly exposing the catalyst to the desulfurization procedure developed in this program caused a continued decline in the catalyst's desulfurized performance. Additional work will be necessary to identify the cause of this performance decline. (5) The rate of sulfur contamination during aging with 78-ppm sulfur fuel increased with repeated aging/desulfurization cycles (from 10% per ten hours to 18% per ten hours). This was not observed with the 3-ppm fuel, where the rate of decline during aging was fairly constant at approximately 2% per ten hours.

None

2000-10-01T23:59:59.000Z

348

Pyrochlore-Based Catalysts for Syngas-Derived Alcohol Synthesis  

gas, coal, or biomass • Enhances the potential use of oxygenates as neat fuels or fuel additives • Develops a catalyst with high selectivity for ...

349

New Catalyst Opens Way to Next-Generation Fuel Cells  

DOE R&D Accomplishments (OSTI)

A new highly stable catalyst developed at Brookhaven Lab lowers barriers to commercial use of fuel cells in vehicles and stationary applications.

Snyder, Kendra

2011-03-28T23:59:59.000Z

350

Advanced high efficiency concentrator cells. Final subcontractor report, 1 October 1988--31 March 1990  

DOE Green Energy (OSTI)

This report describes research to develop the technology needed to demonstrate a monolithic, multijunction, two-terminal, concentrator solar cell with a terrestrial power conversion efficiency greater than 35%. Under three previous subcontracts, Varian developed many of the aspects of a technology needed to fabricate very high efficiency concentrator cells. The current project was aimed at exploiting the new understanding of high efficiency solar cells. Key results covered in this report are as follows. (1) A 1.93-eV AlGaAs/1.42-eV GaAs metal-interconnected cascade cell was manufactured with a one-sun efficiency at 27.6% at air mass 1.5 (AM1.5) global. (2) A 1.0eV InGaAs cell was fabricated on the ``reverse`` side of a low-doped GaAs substrate with a one-sun efficiency of 2.5% AM1.5 diffuse and a short-circuit current of 14.4 mA/cm{sup 2}. (3) Small-scale manufacturing of GaAs p/n concentrator cells was attempted and obtained an excellent yield of high-efficiency cells. (4) Grown-in tunnel junction cell interconnects that are transparent and thermally stable using C and Si dopants were developed. 10 refs.

Gale, R. [Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center

1992-06-01T23:59:59.000Z

351

SunShot Initiative: High-Efficiency Thermal Energy Storage System for CSP  

NLE Websites -- All DOE Office Websites (Extended Search)

High-Efficiency Thermal Energy Storage System for CSP High-Efficiency Thermal Energy Storage System for CSP ANL logo Photo of a black and white porous material magnified 50 times by a microscope. Microstructure of the highly thermal conductive foam that will be used for the prototype TES system. Image from ANL Argonne National Laboratory and project partner Ohio Aerospace Institute, under the National Laboratory R&D competitive funding opportunity, will design, develop, and test a prototype high-temperature and high-efficiency thermal energy storage (TES) system with rapid charging and discharging times. By increasing the efficiency of TES systems, this project aims to lower the capital costs of concentrating solar power (CSP) systems. Approach The research team is developing and evaluating a novel approach for TES at temperatures greater than 700ËšC for CSP systems. The approach uses high thermal conductivity and high-porosity graphite foams infiltrated with a phase change material (PCM) to provide TES in the form of latent heat.

352

L&E: Participate in a field test for high-efficiency troffer lighting. |  

NLE Websites -- All DOE Office Websites (Extended Search)

Lighting & Electrical » Participate Lighting & Electrical » Participate in a field test for high efficiency troffer lighting Activities Technology Solutions Teams Lighting & Electrical Space Conditioning Plug & Process Loads Food Service Refrigeration Laboratories Energy Management & Information Systems Public Sector Teams Market Solutions Teams Participate in a field test for high-efficiency troffer lighting 50% of all commercial fluorescent lighting fixtures are recessed troffers in 1'x4', 2'x2' and 2'x4' configurations, in operation for more than 10 hours a day on average and collectively consuming more than 87 TWh of electricity annually. The Lighting & Electrical team supported the market introduction of high-efficiency troffers by developing a specification that allows for

353

DOE Hydrogen Analysis Repository: Novel Non-Precious Metal Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Novel Non-Precious Metal Catalysts Novel Non-Precious Metal Catalysts Project Summary Full Title: Novel Non-Precious Metal Catalysts for PEMFC: Catalyst Selection through Molecular Modeling and Durability Studies Project ID: 147 Principal Investigator: Branko Popov Brief Description: The University of South Carolina is synthesizing novel non-precious metal electrocatalysts with similar activity and stability as Pt for oxygen reduction reaction (ORR). Keywords: Catalyst; oxygen reduction; non precious metals; molecular modeling; durability Purpose Develop highly active and stable carbon-based metal-free catalysts and carbon composite catalysts with strong Lewis basicity to facilitate the ORR. Performer Principal Investigator: Branko Popov Organization: University of South Carolina Address: 2C19 Swearingen, Chemical Engineering, 301 Main Street

354

Selective methane oxidation over promoted oxide catalysts  

DOE Green Energy (OSTI)

Principal accomplishments have been achieved in all three areas of selective catalytic oxidation of methane that have been pursued in this research project. These accomplishments are centered on the development of catalyst systems that produce high space time yields of C{sub 2} hydrocarbon products, formaldehyde, and methanol from methane/air mixtures at moderate temperatures and at ambient pressure. The accomplishments can be summarized as the following: the SO{sub 4}{sup 2{minus}}/SrO/La{sub 2}O{sub 3} catalyst developed here has been further optimized to produce 2 kg of C{sub 2} hydrocarbons/kg catalyst/hr at 550C; V{sub 2}O{sub 5}SiO{sub 2} catalysts have been prepared that produce up to 1.5 kg formaldehyde/kg catalyst/hr at 630C with CO{sub 2} selectivities; and a novel dual bed catalyst system has been designed and tested that produces over 100 g methanol/kg catalyst/hr at 600C.

Klier, K.; Herman, R.G.

1995-06-01T23:59:59.000Z

355

Measured impacts of high efficiency domestic clothes washers in a community  

SciTech Connect

The US market for domestic clothes washers is currently dominated by conventional vertical-axis washers that typically require approximately 40 gallons of water for each wash load. Although the current market for high efficiency clothes washers that use much less water and energy is quite small, it is growing slowly as manufacturers make machines based on tumble action, horizontal-axis designs available and as information about the performance and benefits of such machines is developed and made available to consumers. To help build awareness of these benefits and to accelerate markets for high efficiency washers, the Department of Energy (DOE), under its ENERGY STAR{reg_sign} Program and in cooperation with a major manufacturers of high efficiency washers, conducted a field evaluation of high efficiency washers using Bern, Kansas as a test bed. Baseline washing machine performance data as well as consumer washing behavior were obtained from data collected on the existing machines of more than 100 participants in this instrumented study. Following a 2-month initial study period, all conventional machines were replaced by high efficiency, tumble-action washers, and the study continued for 3 months. Based on measured data from over 20,000 loads of laundry, the impact of the washer replacement on (1) individual customers` energy and water consumption, (2) customers` laundry habits and perceptions, and (3) the community`s water supply and waste water systems were determined. The study, its findings, and how information from the experiment was used to improve national awareness of high efficiency clothes washer benefits are described in this paper.

Tomlinson, J.; Rizy, T.

1998-07-01T23:59:59.000Z

356

L&E - high efficiency lighting for parking structure | The Better Buildings  

NLE Websites -- All DOE Office Websites (Extended Search)

structure structure Activities Technology Solutions Teams Lighting & Electrical Space Conditioning Plug & Process Loads Food Service Refrigeration Laboratories Energy Management & Information Systems Public Sector Teams Market Solutions Teams Adopt high-efficiency lighting for your parking structure Parking structures and garages are typically lighted by older HID lighting technology without any energy-saving controls. The latest high-efficiency alternatives with energy-saving controls-including light-emitting diode (LED), induction, and fluorescent technology options-can save building owners over 40% on their parking lot lighting bills while delivering additional benefits such as better-lighted spaces. The Lighting & Electrical team developed a performance specification that

357

Fundamental understanding and development of low-cost, high-efficiency silicon solar cells  

DOE Green Energy (OSTI)

The overall objectives of this program are (1) to develop rapid and low-cost processes for manufacturing that can improve yield, throughput, and performance of silicon photovoltaic devices, (2) to design and fabricate high-efficiency solar cells on promising low-cost materials, and (3) to improve the fundamental understanding of advanced photovoltaic devices. Several rapid and potentially low-cost technologies are described in this report that were developed and applied toward the fabrication of high-efficiency silicon solar cells.

ROHATGI,A.; NARASIMHA,S.; MOSCHER,J.; EBONG,A.; KAMRA,S.; KRYGOWSKI,T.; DOSHI,P.; RISTOW,A.; YELUNDUR,V.; RUBY,DOUGLAS S.

2000-05-01T23:59:59.000Z

358

Refractory oxide hosts for a high power, broadly tunable laser with high quantum efficiency and method of making same  

DOE Patents (OSTI)

Refractory oxide crystals having high-quantum efficiency and high thermal stability for use as broadly tunable laser host materials. The crystals are formed by removing hydrogen from a single crystal of the oxide material to a level below about 10/sup 12/ protons per cm/sup 3/ and subsequently thermochemically reducing the oxygen content of the crystal to form sufficient oxygen anion vacancies so that short-lived F/sup +/ luminescence is produced when the crystal is optically excited.

Chen, Yok; Gonzalez, R.

1985-07-03T23:59:59.000Z

359

Refractory oxide hosts for a high power, broadly tunable laser with high quantum efficiency and method of making same  

DOE Patents (OSTI)

Refractory oxide crystals having high-quantum efficiency and high thermal stability for use as broadly tunable laser host materials. The crystals are formed by removing hydrogen from a single crystal of the oxide material to a level below about 10.sup.12 protons per cm.sup.3 and subsequently thermochemically reducing the oxygen content of the crystal to form sufficient oxygen anion vacancies so that short-lived F.sup.+ luminescence is produced when the crystal is optically excited.

Chen, Yok (Oak Ridge, TN); Gonzalez, Roberto (Madrid, ES)

1986-01-01T23:59:59.000Z

360

Nanostructured catalyst supports  

DOE Patents (OSTI)

The present invention relates to SiC nanostructures, including SiC nanopowder, SiC nanowires, and composites of SiC nanopowder and nanowires, which can be used as catalyst supports in membrane electrode assemblies and in fuel cells. The present invention also relates to composite catalyst supports comprising nanopowder and one or more inorganic nanowires for a membrane electrode assembly.

Zhu, Yimin; Goldman, Jay L.; Qian, Baixin; Stefan, Ionel C.

2012-10-02T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Selective methane oxidation over promoted oxide catalysts  

DOE Green Energy (OSTI)

Objective was to selectively oxidize methane to C{sub 2} hydrocarbons and to oxygenates, in particular formaldehyde and methanol, in high space time yields under relatively mild reaction conditions. Results in this document are reported under the headings: methane oxidation over silica, methane oxidation over Sr/La{sub 2}O{sub 3} catalysts, and oxidative coupling of methane over sulfate-doped Sr/La{sub 2}O{sub 3} catalysts. 24 refs, 10 figs, 4 tabs.

Klier, K.; Herman, R.G.

1993-12-31T23:59:59.000Z

362

DEVELOPMENT OF HIGH TEMPERATURE MEMBRANES AND IMPROVED CATHODE CATALYSTS; PROJECT PERIOD JANUARY 1, 2002 - DECEMBER 31, 2005  

DOE Green Energy (OSTI)

Polymer Electrolyte Membranes (PEMs) currently available for fuel cell development work are limited to the temperature range of 60-80°C. For mass commercialization in the transportation arena, three important disadvantages that are linked with the relatively low operating temperature range need to be addressed. These three disadvantages are: (a) sluggish cathode kinetics, (b) CO poisoning at the anode and (c) inefficient thermal characteristics. All three of the above mentioned disadvantages could be solved by increasing the operating temperature range to 100-120°C. To understand the issues associated with high temperature PEMFCs operation, UTCFC has teamed with leading research groups that possess competencies in the field of polymer chemistry. The subcontractors on the program were investigating modified Nafion® and new non-Nafion® based, reinforced and non-reinforced membrane systems. Nafion® based PEMs rely on using high temperature inorganic solid conductor fillers like phosphotungstic acid. Hydrocarbon membrane systems are based on poly (arylene ether sulfone) polymers, PEEK, PAN, etc.

Lesia Protsailo

2006-04-20T23:59:59.000Z

363

Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems  

SciTech Connect

This final report presents and discusses results from a mercury control process development project entitled ''Pilot Testing of Mercury Oxidation Catalysts for Upstream of Wet FGD Systems''. The objective of this project was to demonstrate at pilot scale a mercury control technology that uses solid honeycomb catalysts to promote the oxidation of elemental mercury in the flue gas from coal combustion. Oxidized mercury is removed in downstream wet flue gas desulfurization (FGD) absorbers and leaves with the FGD byproducts. The goal of the project was to achieve 90% oxidation of elemental mercury in the flue gas and 90% overall mercury capture with the downstream wet FGD system. The project was co-funded by EPRI and the U.S. Department of Energy's National Energy Technology Laboratory (DOE NETL) under Cooperative Agreement DE-FC26-01NT41185. Great River Energy (GRE) and City Public Service (now CPS Energy) of San Antonio were also project co-funders and provided host sites. URS Group, Inc. was the prime contractor. Longer-term pilot-scale tests were conducted at two sites to provide catalyst life data. GRE provided the first site, at their Coal Creek Station (CCS), which fires North Dakota lignite, and CPS Energy provided the second site, at their Spruce Plant, which fires Powder River Basin (PRB) coal. Mercury oxidation catalyst testing began at CCS in October 2002 and continued through the end of June 2004, representing nearly 21 months of catalyst operation. An important finding was that, even though the mercury oxidation catalyst pilot unit was installed downstream of a high-efficiency ESP, fly ash buildup began to plug flue gas flow through the horizontal catalyst cells. Sonic horns were installed in each catalyst compartment and appeared to limit fly ash buildup. A palladium-based catalyst showed initial elemental mercury oxidation percentages of 95% across the catalyst, declining to 67% after 21 months in service. A carbon-based catalyst began with almost 98% elemental mercury oxidation across the catalyst, but declined to 79% oxidation after nearly 13 months in service. The other two catalysts, an SCR-type catalyst (titanium/vanadium) and an experimental fly-ash-based catalyst, were significantly less active. The palladium-based and SCR-type catalysts were effectively regenerated at the end of the long-term test by flowing heated air through the catalyst overnight. The carbon-based catalyst was not observed to regenerate, and no regeneration tests were conducted on the fourth, fly-ash-based catalyst. Preliminary process economics were developed for the palladium and carbon-based catalysts for a scrubbed, North Dakota lignite application. As described above, the pilot-scale results showed the catalysts could not sustain 90% or greater oxidation of elemental mercury in the flue gas for a period of two years. Consequently, the economics were based on performance criteria in a later DOE NETL solicitation, which required candidate mercury control technologies to achieve at least a 55% increase in mercury capture for plants that fire lignite. These economics show that if the catalysts must be replaced every two years, the catalytic oxidation process can be 30 to 40% less costly than conventional (not chemically treated) activated carbon injection if the plant currently sells their fly ash and would lose those sales with carbon injection. If the plant does not sell their fly ash, activated carbon injection was estimated to be slightly less costly. There was little difference in the estimated cost for palladium versus the carbon-based catalysts. If the palladium-based catalyst can be regenerated to double its life to four years, catalytic oxidation process economics are greatly improved. With regeneration, the catalytic oxidation process shows over a 50% reduction in mercury control cost compared to conventional activated carbon injection for a case where the plant sells its fly ash. At Spruce Plant, mercury oxidation catalyst testing began in September 2003 and continued through the end of April 2005, interrupted only by a

Richard Rhudy

2006-06-30T23:59:59.000Z

364

TECHNOLOGY DEVELOPMENT FOR IRON FISCHER-TROPSCH CATALYSTS  

DOE Green Energy (OSTI)

The goal of the proposed work described in this Final Report was the development of iron-based Fischer-Tropsch catalysts that combined high activity, selectivity and life with physical robustness for slurry phase reactors that will produce either low-alpha or high-alpha products. The work described here has optimized the catalyst composition and pretreatment operation for a low-alpha catalyst. In parallel, work has been conducted to design a high-alpha iron catalyst that is suitable for slurry phase synthesis. Studies have been conducted to define the chemical phases present at various stages of the pretreatment and synthesis stages and to define the course of these changes. The oxidation/reduction cycles that are anticipated to occur in large, commercial reactors have been studied at the laboratory scale. Catalyst performance has been determined for catalysts synthesized in this program for activity, selectivity and aging characteristics.

Davis, B.H.

1998-07-22T23:59:59.000Z

365

Status of SiC Power Devices for Compact High Efficiency High ...  

Science Conference Proceedings (OSTI)

... Si Circuits and, hence, 1- 3 % fuel savings for ... Distributed Systems in multiple locations for energy distribution and ... High temp/ density storage & ...

2012-06-08T23:59:59.000Z

366

Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production  

DOE Green Energy (OSTI)

The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe, and proliferation-resistant. High-temperature reactor systems allow higher electrical generating efficiencies and high-temperature process heat applications, such as thermo-chemical hydrogen production. The study focused on three concepts; one using molten salt coolant with a prismatic fuel-element geometry, the other two using high-pressure helium coolant with a prismatic fuel-element geometry and a fuel-pebble element design. Peak operating temperatures, passive-safety, decay heat removal, criticality, burnup, reactivity coefficients, and material issues were analyzed to determine the technical feasibility of each concept.

PARMA JR.,EDWARD J.; PICKARD,PAUL S.; SUO-ANTTILA,AHTI JORMA

2003-06-01T23:59:59.000Z

367

The design of a high efficiency RF power amplifier for an MCM process  

E-Print Network (OSTI)

In this thesis, I addressed issues arising in the design of a high efficiency RF power amplifier for the Draper Laboratory multi-chip module (MCM) process. A design for a 2.3 GHz PCB amplifier using an enhancement-mode ...

Noonan, James (James Keating)

2005-01-01T23:59:59.000Z

368

2004 ASHRAE. 3 Standing column wells can be used as highly efficient  

E-Print Network (OSTI)

©2004 ASHRAE. 3 ABSTRACT Standing column wells can be used as highly efficient ground heat Performance Simon J. Rees, Ph.D. Jeffrey D. Spitler, Ph.D., P.E. Zheng Deng Member ASHRAE Member ASHRAE Student Member ASHRAE Carl D. Orio Carl N. Johnson, Ph.D. Member ASHRAE Member ASHRAE Simon J. Rees

369

Effect of High Efficiency Lighting on Power Quality in Public Buildings  

Science Conference Proceedings (OSTI)

This power quality (PQ) case study investigates the effect of high efficiency lighting on PQ in public buildings. The buildings scheduled for lighting retrofits that were involved in this study include a graduate center, a hospital facility, and a social services building.

2003-12-31T23:59:59.000Z

370

High efficient numerical techniques for the earthing design and the analysis of grounded phenomena  

E-Print Network (OSTI)

" or "earthing" system of an electrical substation comprises all interconnected grounding fa- cilitiesHigh efficient numerical techniques for the earthing design and the analysis of grounded phenomena for the computational design of grounding systems of electrical installations in uniform and layered soils

Colominas, Ignasi

371

High efficiency light emitting diode with anisotropically etched GaN-sapphire interface  

E-Print Network (OSTI)

High efficiency light emitting diode with anisotropically etched GaN- sapphire interface M. H. Lo and optimization of a light-emitting diode projection micro-stereolithography three-dimensional manufacturingGaN micro-light emitting diodes Appl. Phys. Lett. 101, 231110 (2012) A bright cadmium-free, hybrid organic

372

Highly-efficient noise-assisted energy transport in classical oscillator systems  

E-Print Network (OSTI)

Photosynthesis is a biological process that involves the highly-efficient transport of energy captured from the sun to a reaction center, where conversion into useful biochemical energy takes place. Even though one can always use a quantum perspective to describe any physical process, since everything follows the laws of Quantum Mechanics, is the use of quantum theory imperative to explain this high efficiency? Making use of the quantum-classical correspondence of electronic energy transfer recently introduced by Eisfeld and Briggs [Phys. Rev. E 85, 046118 (2012)], we show here that the highly-efficient noise-assisted energy transport described by Rebentrost et al. [New J. Phys. 11, 033003 (2009)], and Plenio and Huelga [New J. Phys. 10, 113019 (2008)], as the result of the interplay between the quantum coherent evolution of the photosynthetic system and noise introduced by its surrounding environment, it can be found as well in purely classical systems. The wider scope of applicability of the enhancement of energy transfer assisted by noise might open new ways for developing new technologies aimed at enhancing the efficiency of a myriad of energy transfer systems, from information channels in micro-electronic circuits to long-distance high-voltage electrical lines.

R. de J. León-Montiel; Juan P. Torres

2013-01-08T23:59:59.000Z

373

Development of a stable cobalt-ruthenium Fisher-Tropsch catalyst. Final report  

DOE Green Energy (OSTI)

The reverse micelle catalyst preparation method has been used to prepare catalysts on four supports: magnesium oxide, carbon, alumina- titania and steamed Y zeolite. These catalysts were not as active as a reference catalyst prepared during previous contracts to Union Carbide Corp. This catalyst was supported on steamed Y zerolite support and was impregnated by a pore-filling method using a nonaqueous solvent. Additional catalysts were prepared via pore- filling impregnation of steamed Y zeolites. These catalysts had levels of cobalt two to three and a half times as high as the original Union Carbide catalyst. On a catalyst volume basis they were much more active than the previous catalyst; on an atom by atom basis the cobalt was about of the same activity, i.e., the high cobalt catalysts` cobalt atoms were not extensively covered over and deactivated by other cobalt atoms. The new, high activity, Y zerolite catalysts were not as stable as the earlier Union Carbide catalyst. However, stability enhancement of these catalysts should be possible, for instance, through adjustment of the quantity and/or type of trace metals present. A primary objective of this work was determination whether small amounts of ruthenium could enhance the activity of the cobalt F-T catalyst. The reverse micelle catalysts were not activated by ruthenium, indeed scanning transmission electronic microscopy (STEM) analysis provided some evidence that ruthenium was not present in the cobalt crystallites. Ruthenium did not seem to activate the high cobalt Y zeolite catalyst either, but additional experiments with Y zeolite-supported catalysts are required. Should ruthenium prove not to be an effective promoter under the simple catalyst activation procedure used in this work, more complex activation procedures have been reported which are claimed to enhance the cobalt/ruthenium interaction and result in activity promotion by ruthenium.

Frame, R.R.; Gala, H.B.

1995-02-01T23:59:59.000Z

374

Energy efficient Phase Change Memory based main memory for future high performance systems  

Science Conference Proceedings (OSTI)

Phase Change Memory (PCM) has recently attracted a lot of attention as a scalable alternative to DRAM for main memory systems. As the need for high-density memory increases, DRAM has proven to be less attractive from the point of view of scaling and ... Keywords: DDR3 commodity DRAM memory system, energy efficient phase change memory, main memory, future high performance systems, energy consumption, latency issues, write energy, write endurance, cache, embedded DRAM

R. A. Bheda; Jason A. Poovey; J. G. Beu; T. M. Conte

2011-07-01T23:59:59.000Z

375

Rapid thermal processing of high-efficiency silicon solar cells with controlled in-situ annealing  

DOE Green Energy (OSTI)

Silicon solar cell efficiencies of 17.1%, 16.4%, 14.8%, and 14.9% have been achieved on FZ, Cz, multicrystalline (mc-Si), and dendritic web (DW) silicon, respectively, using simplified, cost-effective rapid thermal processing (RTP). These represent the highest reported efficiencies for solar cells processed with simultaneous front and back diffusion with no conventional high-temperature furnace steps. Appropriate diffusion temperature coupled with the added in-situ anneal resulted in suitable minority-carrier lifetime and diffusion profiles for high-efficiency cells. The cooling rate associated with the in-situ anneal can improve the lifetime and lower the reverse saturation current density (J{sub 0}), however, this effect is material and base resistivity specific. PECVD antireflection (AR) coatings provided low reflectance and efficient front surface and bulk defect passivation. Conventional cells fabricated on FZ silicon by furnace diffusions and oxidations gave an efficiency of 18.8% due to greater short wavelength response and lower J{sub 0}.

Doshi, P.; Rohatgi, A.; Ropp, M.; Chen, Z. [Georgia Institute of Technology, Atlanta, GA (United States). Univ. Center of Excellence for Photovoltaics Research and Education; Ruby, D. [Sandia National Labs., Albuquerque, NM (United States); Meier, D.L. [EBARA Solar, Inc., Large, PA (United States)

1995-01-01T23:59:59.000Z

376

Los Alamos catalyst could jumpstart e-cars, green energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst could jumpstart e-cars, green energy Catalyst could jumpstart e-cars, green energy Los Alamos catalyst could jumpstart e-cars, green energy The new material has the highest oxygen reduction reaction (ORR) activity in alkaline media of any non-precious metal catalyst developed to date. June 4, 2013 A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National Laboratory) A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National

377

Los Alamos catalyst could jumpstart e-cars, green energy  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst could jumpstart e-cars, green energy Catalyst could jumpstart e-cars, green energy Los Alamos catalyst could jumpstart e-cars, green energy The new material has the highest oxygen reduction reaction (ORR) activity in alkaline media of any non-precious metal catalyst developed to date. June 4, 2013 A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National Laboratory) A high-resolution microscopic image of a new type of nanostructured-carbon-based catalyst developed at Los Alamos National Laboratory that could pave the way for reliable, economical next-generation batteries and alkaline fuel cells. (Photo credit: Los Alamos National

378

Three way conversion catalysts for automotive pollution abatement  

Science Conference Proceedings (OSTI)

The revisions to the Clean Air Act of 1990 and recent regulatory actions taken by the California Air Resources Board mandate the development of automobiles with much lower tailpipe emissions. For the original equipment manufacturers (OEM`s) to meet the target fleet emissions numbers for automobiles defined in California`s Low Emission Vehicle program, the OEM`s must qualify each model into one of the emissions categories defined in Table 1. The emissions are calculated using the Federal Test Procedure (FTP) protocol wherein a test vehicle fitted with a catalytic converter is driven on a chassis rolls over a tightly defined driving cycle. A key feature of the evaluation is that the FTP is conducted after the catalyst has dealt with 50,000 - 100,000 miles of raw engine exhaust. During the FTP, 50 - 90% of the total pollutants emitted to the atmosphere by the vehicle occurs immediately following the startup of the engine when the engine block and manifold am cold, and the catalytic converter has not reached high conversion efficiencies, and are known as {open_quotes}cold start{close_quotes} emissions. The stringency of the regulations becomes evident when to qualify for either Low Emission Vehicle (LEV) or Ultra Low Emission Vehicle (ULEV) status, the hydrocarbon engine out emissions of 2.0 g/mile, typical for a six cylinder vehicle, must be reduced over the entire FTP by 970/9 and 99%, respectively. These regulations spurred a variety of new technology thrusts aimed at attacking the cold start hydrocarbons including electrically heated catalysts, hydrocarbon traps, exhaust gas burners, and close coupled catalysts. This report describes the performance of palladium catalysts for the air pollution control of nitrogen oxides.

Burk, P.L.; Zhicheng Hu; Rabinowitz, H.N.; Tauster, S.J.; Chen, Shau-Lin F. [Engelhard Corp., Iselin, NJ (United States)

1996-12-31T23:59:59.000Z

379

Evaluation of high-energy-efficiency powertrain approaches: the 1996 futurecar challenge  

DOE Green Energy (OSTI)

Twelve colleges and universities were selected to design, build, and develop a mid-size vehicle that could achieve high energy economy while maintaining the performance characteristics of today`s mid-size vehicle. Many of the teams were able to increase the fuel economy of their vehicles, but most of these increases came at the expense of decreased performance or worsened emissions. This paper evaluates and summarizes the high-energy-efficiency powertrain technology approaches that were utilized in the 1996 FutureCar Challenge, which was the first evaluation of these vehicles in a two-year program. Of the 11 vehicles evaluated in the competition, nine utilized hybrid electric vehicle approaches. This paper discusses the design trade- offs made by the teams to achieve high efficiency while trying to maintain stock performance.

Sluder, S.; Duoba, M.; Larsen, R.

1997-02-01T23:59:59.000Z

380

High Temperature Superconducting Magnets for Efficient Low Energy Beam Transport Systems  

E-Print Network (OSTI)

Modern ion accelerators and ion implantation systems need very short, highly versatile, Low Energy Beam Transport (LEBT) systems. The need for reliable and continuous operation requires LEBT designs to be simple and robust. The energy efficiency of available high temperature superconductors (HTS), with efficient and simple cryocooler refrigeration, is an additional attraction. Innovative, compact LEBT systems based on solenoids designed and built with high-temperature superconductor will be developed using computer models and prototyped. The parameters will be chosen to make this type of LEBT useful in a variety of ion accelerators, ion implantation systems, cancer therapy synchrotrons, and research accelerators, including the ORNL SNS. The benefits of solenoids made with HTS will be evaluated with analytical and numerical calculations for a two-solenoid configuration, as will be used in the SNS prototype LEBT that will replace the electrostatic one at SNS, and a single solenoid configuration, as was proposed...

Popovic, M; Johnson, R P; Nipper, J H

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Light Trapping for High Efficiency Heterojunction Crystalline Si Solar Cells: Preprint  

DOE Green Energy (OSTI)

Light trapping plays an important role to achieve high short circuit current density (Jsc) and high efficiency for amorphous/crystalline Si heterojunction solar cells. Si heterojunction uses hydrogenated amorphous Si for emitter and back contact. This structure of solar cell posses highest open circuit voltage of 0.747 V at one sun for c-Si based solar cells. It also suggests that over 25% record-high efficiency is possible with further improvement of Jsc. Light trapping has two important tasks. The first one is to reduce the surface reflectance of light to zero for the solar spectrum that Si has a response. The second one is to increase the effective absorption length to capture all the photon. For Si heterojunction solar cell, surface texturing, anti-reflectance indium tin oxides (ITO) layer at the front and back are the key area to improve the light trapping.

Wang, Q.; Xu, Y.; Iwaniczko, E.; Page, M.

2011-04-01T23:59:59.000Z

382

Preparation of a novel structured catalyst based on aligned carbon nanotube arrays for a microchannel Fischer-Tropsch synthesis reactor  

SciTech Connect

A novel catalyst microstructure based on aligned multiwall carbon nanotube arrays was synthesized. Its advanced heat and mass transport characteristics coupled with high surface area led to superior performances for Fischer-Tropsch synthesis in a microchannel chemical reactor. The fabrication of such a novel catalyst structure first involved metalorganic chemical vapor deposition (MOCVD) growth of a dense Al2O3 thin film over FeCrAlY foam substrate to enhance adhesion between catalyst layer and metal substrate. Aligned arrays of multiwall carbon nanotubes were grown over the substrate by catalytic decomposition of ethylene. These nanotube bundles were directly attached to the FeCrAlY substrate through a thin layer of oxide thin film. When the outer surfaces of nanobundles were coated with a catalyst layer, a unique hierarchical catalyst structure with nanoporous interstitials between the bundles was created. Thus, engineered catalysts based on such a novel hierarchical structure minimizes mass transfer encountered in the gas-liquid-solid three phase reactions. In addition, high thermal conductivity of carbon nanotube and the direct attachment of these nanobundles to the metal foam allow efficient heat removal from catalytic sites. The advanced heat and mass transfer on this novel structured catalyst was demonstrated in Fischer-Tropsch synthesis in a microchannel fixed bed reactor. The presence of carbon nanotube arrays improved dispersion of active metals and reduced mass transfer limitation, leading to a factor of four enhancement of Fischer-Tropsch synthesis activity. The improved temperature control with the carbon nanotube arrays also allows the Fischer-Tropsch synthesis being operated at temperatures as high as 265 C without reaction runaway favoring methane formation.

Chin, Ya-Huei; Hu, Jianli; Cao, Chunshe; Gao, Yufei; Wang, Yong

2005-12-15T23:59:59.000Z

383

A high resolution finite volume method for efficient parallel simulation of casting processes on unstructured meshes  

SciTech Connect

We discuss selected aspects of a new parallel three-dimensional (3-D) computational tool for the unstructured mesh simulation of Los Alamos National Laboratory (LANL) casting processes. This tool, known as {bold Telluride}, draws upon on robust, high resolution finite volume solutions of metal alloy mass, momentum, and enthalpy conservation equations to model the filling, cooling, and solidification of LANL castings. We briefly describe the current {bold Telluride} physical models and solution methods, then detail our parallelization strategy as implemented with Fortran 90 (F90). This strategy has yielded straightforward and efficient parallelization on distributed and shared memory architectures, aided in large part by new parallel libraries {bold JTpack9O} for Krylov-subspace iterative solution methods and {bold PGSLib} for efficient gather/scatter operations. We illustrate our methodology and current capabilities with source code examples and parallel efficiency results for a LANL casting simulation.

Kothe, D.B.; Turner, J.A.; Mosso, S.J. [Los Alamos National Lab., NM (United States); Ferrell, R.C. [Cambridge Power Computer Assoc. (United States)

1997-03-01T23:59:59.000Z

384

Direct drive heavy-ion-beam inertial fusion at high coupling efficiency  

SciTech Connect

Issues with coupling efficiency, beam illumination symmetry, and Rayleigh-Taylor instability are discussed for spherical heavy-ion-beam-driven targets with and without hohlraums. Efficient coupling of heavy-ion beams to compress direct-drive inertial fusion targets without hohlraums is found to require ion range increasing several-fold during the drive pulse. One-dimensional implosion calculations using the LASNEX inertial confinement fusion target physics code shows the ion range increasing fourfold during the drive pulse to keep ion energy deposition following closely behind the imploding ablation front, resulting in high coupling efficiencies (shell kinetic energy/incident beam energy of 16% to 18%). Ways to increase beam ion range while mitigating Rayleigh-Taylor instabilities are discussed for future work.

Logan, B.G.; Perkins, L.J.; Barnard, J.J.

2008-05-16T23:59:59.000Z

385

New concepts for high efficiency energy conversion: The avalanche heterostructure and superlattice solar cells  

DOE Green Energy (OSTI)

This report describes investigation into the theory and technology of a novel heterojunction or superlattice, single-junction solar cell, which injects electrons across the heterointerface to produce highly efficient impact ionization of carriers in the lowband-gap side of the junction, thereby conserving their total energy. Also, the superlattice structure has the advantage of relaxing the need for perfect lattice matching at the p-n interface and will inhibit the cross diffusion of dopant atoms that typically occurs in heavy doping. This structure avoids the use of tunnel junctions that make it very difficult to achieve the predicted efficiencies in cascade cells, thus making it possible to obtain energy efficiencies that are competitive with those predicted for cascade solar cells with reduced complexity and cost. This cell structure could also be incorporated into other solar cell structures designed for wider spectral coverage.

Summers, C.J.; Rohatgi, A.; Torabi, A.; Harris, H.M. (Georgia Tech Research Inst., Atlanta, GA (United States))

1993-01-01T23:59:59.000Z

386

High Efficient Secret Key Distillation for Long Distance Continuous Variable Quantum Key Distribution  

E-Print Network (OSTI)

The continuous variable quantum key distribution is expected to provide high secret key rate without single photon source and detector, but the lack of the secure and effective key distillation method makes it unpractical. Here, we present a secure single-bit-reverse-reconciliation protocol combined with secret information concentration and post-selection, which can distill the secret key with high efficiency and low computational complexity. The simulation results show that this protocol can provide high secret key rate even when the transmission fiber is longer than 150km, which may make the continuous variable scheme to outvie the single photon one.

Yi-bo Zhao; Zheng-fu Han; Jin-jian Chen; You-zhen Gui; Guang-can Guo

2006-03-08T23:59:59.000Z

387

Catalyst for microelectromechanical systems microreactors  

DOE Patents (OSTI)

A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

Morse, Jeffrey D. (Martinez, CA); Sopchak, David A. (Livermore, CA); Upadhye, Ravindra S. (Pleasanton, CA); Reynolds, John G. (San Ramon, CA); Satcher, Joseph H. (Patterson, CA); Gash, Alex E. (Brentwood, CA)

2011-11-15T23:59:59.000Z

388

Catalyst for microelectromechanical systems microreactors  

DOE Patents (OSTI)

A microreactor comprising a silicon wafer, a multiplicity of microchannels in the silicon wafer, and a catalyst coating the microchannels. In one embodiment the catalyst coating the microchannels comprises a nanostructured material. In another embodiment the catalyst coating the microchannels comprises an aerogel. In another embodiment the catalyst coating the microchannels comprises a solgel. In another embodiment the catalyst coating the microchannels comprises carbon nanotubes.

Morse, Jeffrey D. (Martinez, CA); Sopchak, David A. (Livermore, CA); Upadhye, Ravindra S. (Pleasanton, CA); Reynolds, John G. (San Ramon, CA); Satcher, Joseph H. (Patterson, CA); Gash, Alex E. (Brentwood, CA)

2010-06-29T23:59:59.000Z

389

Catalysts and method  

DOE Patents (OSTI)

An improved catlayst and method for the oxyhydrochlorination of methane is disclosed. The catalyst includes a pyrogenic porous support on which is layered as active material, cobalt chloride in major proportion, and minor proportions of an alkali metal chloride and of a rare earth chloride. On contact of the catalyst with a gas flow of methane, HC1 and oxygen, more than 60% of the methane is converted and of that converted more than 40% occurs as monochloromethane. Advantageously, the monochloromethane can be used to produce gasoline boiling range hydrocarbons with the recycle of HCl for further reaction. This catalyst is also of value for the production of formic acid as are analogous catalysts with lead, silver or nickel chlorides substituted for the cobalt chloride.

Taylor, Charles E. (Pittsburgh, PA); Noceti, Richard P. (Pittsburgh, PA)

1991-01-01T23:59:59.000Z

390

Uranium-Based Catalysts  

NLE Websites -- All DOE Office Websites (Extended Search)

Uranium-Based Catalysts S. H. Overbury, Cyrus Riahi-Nezhad, Zongtao Zhang, Sheng Dai, and Jonathan Haire Oak Ridge National Laboratory* P.O. Box 2008 Oak Ridge, Tennessee...

391

Phase II Final Project Report SBIR Project: "A High Efficiency PV to Hydrogen Energy System"  

Science Conference Proceedings (OSTI)

The innovative research conducted for this project contributed greatly to the understanding of generating low-cost hydrogen from solar energy. The project’s research identified two highly leveraging and complementary pathways. The first pathway is to dramatically increase the efficiency of converting sunlight into electricity. Improving solar electric conversion efficiency directly increases hydrogen production. This project produced a world record efficiency for silicon solar cells and contributed to another world record efficiency for a solar concentrator module using multijunction solar cells. The project’s literature review identified a second pathway in which wasted heat from the solar concentration process augments the electrolysis process generating hydrogen. One way to do this is to use a “heat mirror” that reflects the heat-producing infrared and transmits the visible spectrum to the solar cells; this also increases solar cell conversion efficiency. An economic analysis of this concept confirms that, if long-term concentrator photovoltaic (CPV) and solid-oxide electrolyzer cost goals can be achieved, hydrogen will be produced from solar energy cheaper than the cost of gasoline. The potential public benefits from this project are significant. The project has identified a potential energy source for the nation’s future electricity and transportation needs that is entirely “home grown” and carbon free. As CPV enter the nation’s utility markets, the opportunity for this approach to be successful is greatly increased. Amonix strongly recommends further exploration of this project’s findings.

Slade, A; Turner, J; Stone, K; McConnell, R

2008-09-02T23:59:59.000Z

392

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, Rayford G. (Bryan, TX); Dosch, Robert G. (Albuquerque, NM)

1993-01-01T23:59:59.000Z

393

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, R.G.; Dosch, R.G.

1991-12-31T23:59:59.000Z

394

Crystalline titanate catalyst supports  

DOE Patents (OSTI)

A series of new crystalline titanates (CT) are shown to have considerable potential as catalyst supports. For Pd supported catalyst, the catalytic activity for pyrene hydrogenation was substantially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide supports.

Anthony, R.G.; Dosch, R.G.

1993-01-05T23:59:59.000Z

395

Plasmatron-catalyst system  

DOE Patents (OSTI)

A plasmatron-catalyst system. The system generates hydrogen-rich gas and comprises a plasmatron and at least one catalyst for receiving an output from the plasmatron to produce hydrogen-rich gas. In a preferred embodiment, the plasmatron receives as an input air, fuel and water/steam for use in the reforming process. The system increases the hydrogen yield and decreases the amount of carbon monoxide.

Bromberg, Leslie (Sharon, MA); Cohn, Daniel R. (Chestnut Hill, MA); Rabinovich, Alexander (Swampscott, MA); Alexeev, Nikolai (Moscow, RU)

2007-10-09T23:59:59.000Z

396

Catalytic reforming catalyst  

Science Conference Proceedings (OSTI)

An improved catalyst, having a reduced fouling rate when used in a catalytic reforming process, said catalyst comprising platinum disposed on an alumina support wherein the alumina support is obtained by removing water from aluminum hydroxide produced as a by-product from a ziegler higher alcohol synthesis reaction, and wherein the alumina is calcined at a temperature of 1100-1400/sup 0/F so as to have a surface area of 165 to 215 square meters per gram.

Buss, W.C.; Kluksdahl, H.E.

1980-12-09T23:59:59.000Z

397

High efficiency multilayer blazed gratings for EUV and soft X-rays: Recent developments  

Science Conference Proceedings (OSTI)

Multilayer coated blazed gratings with high groove density are the best candidates for use in high resolution EUV and soft x-ray spectroscopy. Theoretical analysis shows that such a grating can be potentially optimized for high dispersion and spectral resolution in a desired high diffraction order without significant loss of diffraction efficiency. In order to realize this potential, the grating fabrication process should provide a perfect triangular groove profile and an extremely smooth surface of the blazed facets. Here we report on recent progress achieved at the Advanced Light Source (ALS) in fabrication of high quality multilayer coated blazed gratings. The blazed gratings were fabricated using scanning beam interference lithography followed by wet anisotropic etching of silicon. A 200 nm period grating coated with a Mo/Si multilayer composed with 30 bi-layers demonstrated an absolute efficiency of 37.6percent in the 3rd diffraction order at 13.6 nm wavelength. The groove profile of the grating was thoroughly characterized with atomic force microscopy before and after the multilayer deposition. The obtained metrology data were used for simulation of the grating efficiency with the vector electromagnetic PCGrate-6.1 code. The simulations showed that smoothing of the grating profile during the multilayer deposition is the main reason for efficiency losses compared to the theoretical maximum. Investigation of the grating with cross-sectional transmission electron microscopy revealed a complex evolution of the groove profile in the course of the multilayer deposition. Impact of the shadowing and smoothing processes on growth of the multilayer on the surface of the sawtooth substrate is discussed.

Voronov, Dmitriy; Ahn, Minseung; Anderson, Erik; Cambie, Rossana; Chang, Chih-Hao; Goray, Leonid; Gullikson, Eric; Heilmann, Ralf; Salmassi, Farhad; Schattenburg, Mark; Warwick, Tony; Yashchuk, Valeriy; Padmore, Howard

2011-07-26T23:59:59.000Z

398

High-efficiency cadmium and zinc-telluride-based thin-film solar cells  

DOE Green Energy (OSTI)

This report describes research into polycrystalline CdTe solar cells grown by metal-organic chemical vapor deposition. Efficiencies of {approximately}10% were achieved using both p-i-n and p-n structures. A pre-heat treatment of CdS/SnO{sub 2}/glass substrates at 450{degrees}C in hydrogen atmosphere prior to the CdTe growth was found to be essential for high performance because this heat treatment reduces oxygen-related defects from the CdS surface. However, this treatment also resulted in a Cd-deficient CdS surface, which may in part limit the CdTe cell efficiency to 10% due to Cd vacancy-related interface defects. Preliminary model calculations suggest that removing these states can increase the cell efficiency from 10% to 13.5%. Photon absorption in the CdS film also limits the cell performance, and eliminating this loss mechanism can result in CdTe efficiencies in excess of 18%. Polycrystalline, 1.7-e, CdZnTe films were also grown for tandem-cell applications. CdZnTe/CdS cells processed using the standard CdTe cell fabrication procedure resulted in 4.4% efficiency, high series resistance, and a band-gap shift to 1.55 eV. The formation of Zn-O at and near the CdZnTe surface is the source of high contact resistance. A saturated dichromate each prior to contact deposition was found to solve the contact resistance problem. The CdCl{sub 2} treatment was identified as the cause of the observed band-gap shift due to the preferred formation of ZnCl{sub 2}. 59 refs.

Rohatgi, A.; Sudharsanan, R.; Ringel, S. (Georgia Inst. of Tech., Atlanta, GA (United States))

1992-02-01T23:59:59.000Z

399

The Importance of Domain Size and Purity in High-Efficiency Organic Solar  

NLE Websites -- All DOE Office Websites (Extended Search)

The Importance of Domain Size The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells The Importance of Domain Size and Purity in High-Efficiency Organic Solar Cells Print Wednesday, 27 March 2013 00:00 The efficiency of polymer/organic photovoltaic cells hinges on excitons-electron/hole pairs energized by sunlight-getting to the interfaces of donor and acceptor domains quickly, before recombining. At the interfaces, they become free charges that must then reach device electrodes. With the discovery of mixed domains of donor and acceptor molecules, many have pictured the excitons' journey as easy (interfaces are everywhere) but the charges' journey as precarious (interfaces are everywhere). Instead, using a combination of x-ray scattering and microscopy techniques, researchers have found that excitons may actually not fare so well in mixed domains but need access to pure aggregates to efficiently convert into charges. The smaller the aggregates, the better, allowing increased interfacial area and dramatic increases in device performance.

400

Research on high-efficiency, single-junction, monolithic, thin-film amorphous silicon solar cells  

DOE Green Energy (OSTI)

This document describes the progress made in obtaining stable, a-Si-based submodules that have a large area and high efficiency. Conversion efficiencies of up to 11.95% were obtained in small-area, single-junction a-Si solar cells using textured TiO{sub 2}, superlattice p-layers, graded carbon concentrations near the p/i interface, and highly reflective ITO/silver back contacts. Single- junction a-SiC and a-SiGe p-i-n cells were also fabricated that had conversion efficiencies of 9%--11%, and some recently fabricated stacked-junction cells had conversion efficiencies of about 10%. In materials research boron-doped microcrystalline SiC films were recently developed containing up to 6 at. % carbon with conductivities of 3 {times} 10{sup {minus}3}/{Omega}-cm at room temperature and activation energies of 0.11 eV. Microcrystalline film growth was shown to be strongly influenced by the nature of the substrate, with nucleation occurring more readily on a-Si substrates than on TiO{sub 2}. Stability studies show that light-induced degradation is usually enhanced by the presence of carbon grading near the p/i interface. In general, adding either germanium (from GeH{sub 4}) or carbon (from CH{sub 4}) to the i-layer of a p-i-n cell leads to enhanced light-induced degradation. 13 refs., 80 figs., 17 tabs.

Catalano, A.W.; Carlson, D.E.; Ayra, R.R.; Bennett, M.S.; D'Aiello, R.V.; Dickson, C.R.; Fortmann, C.M.; Goldstein, B.; McVeigh, J.; Morris, J.; Newton, J.L.; Wiedeman, S. (Solarex Corp., Newtown, PA (USA). Thin Film Div.)

1989-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Asynchronous and Multiprecision Linear Solvers - Scalable and Fault-Tolerant Numerics for Energy Efficient High Performance Computing.  

E-Print Network (OSTI)

??Asynchronous methods minimize idle times by removing synchronization barriers, and therefore allow the efficient usage of computer systems. The implied high tolerance with respect to… (more)

Anzt, Hartwig

2012-01-01T23:59:59.000Z

402

Highly Efficient 32.3% Monolithic GaInP/GaAs/Ge Triple Junction Concentrator Solar Cells  

DOE Green Energy (OSTI)

Based on recent cell improvements for space applications, multijunction cells apear to be ideal candidates for high efficiency, cost effective, PV concentrator systems.

Cotal, H. L.; Lillington, D. R.; Ermer, J. H.; King, R. R.; Karam, N. H.; Kurtz, S. R.; Friedman, D. J.; Olson, J. M.; Ward, S.; Duda, A.; Emery, K. A.; Moriarty, T.

2000-01-01T23:59:59.000Z

403

Regulated Emissions from a High Efficiency Spark-Ignition with Maximum Engine Power at or Below 19 KW.  

E-Print Network (OSTI)

??Previous research has developed a set of high efficiency generator engines converted from a stock automobile engine. These all employed different variations of squish and… (more)

Mackey, Travis J

2013-01-01T23:59:59.000Z

404

Development and Applications of Pd Catalysts for C-N Cross-Coupling Reactions  

E-Print Network (OSTI)

Chapter 1 A procedure for forming a highly active Pd(0) catalyst from Pd(OAc) 2, water, and biarylphosphine ligands has been developed. This protocol generates a catalyst system, which exhibits excellent reactivity and ...

Fors, Brett P

2011-01-01T23:59:59.000Z

405

High-efficiency silicon solar cells for use with a prismatic cover at 160 suns  

DOE Green Energy (OSTI)

For this program, Solarex developed a process sequence that could be used in a manufacturing environment to produce high-efficiency silicon concentrator cells. The cells had large gridlines to minimize series resistance losses and a prismatic cover to minimize shadowing. The front surface of the cell was textured to improve absorption of light and passivated to reduce front-surface recombination. Two separate diffusions steps were used: a deep emitter with a light surface concentration and a heavy diffusion to reduce recombination under the front contacts. Cell efficiencies as high as 22.25% were demonstrated at 75 suns and over 21.5% at 150 suns air mass 1.5 illumination. 16 refs., 31 figs., 10 tabs.

Silver, J.R.; Patel, B. (Solarex Corp., Rockville, MD (USA))

1990-08-01T23:59:59.000Z

406

Simulation of a High Efficiency Multi-bed Adsorption Heat Pump  

Science Conference Proceedings (OSTI)

Attaining high energy efficiency with adsorption heat pumps is challenging due to thermodynamic losses that occur when the sorbent beds are thermally cycled without effective heat recuperation. The multi-bed concept described here effectively transfers heat from beds being cooled to beds being heated, which enables high efficiency in thermally driven heat pumps. A simplified lumped-parameter model and detailed finite element analysis are used to simulate the performance of an ammonia-carbon sorption compressor, which is used to project the overall heat pump coefficient of performance. The effects of bed geometry and number of beds on system performance are explored, and the majority of the performance benefit is obtained with four beds. Results indicate that a COP of 1.24 based on heat input is feasible at AHRI standard test conditions for residential HVAC equipment. When compared on a basis of primary energy input, performance equivalent to SEER 13 or 14 are theoretically attainable with this system.

TeGrotenhuis, Ward E.; Humble, Paul H.; Sweeney, J. B.

2012-05-01T23:59:59.000Z

407

The high-efficiency ?-ray spectroscopy setup ?3 at HI?S  

E-Print Network (OSTI)

The existing Nuclear Resonance Fluorescence (NRF) setup at the HI{\\gamma}S facility at the Triangle Universities Nuclear Laboratory at Duke University has been extended in order to perform {\\gamma}-{\\gamma} coincidence experiments. The new setup combines large volume LaBr3:Ce detectors and high resolution HPGe detectors in a very close geometry to offer high efficiency, high energy resolution as well as high count rate capabilities at the same time. The combination of a highly efficient {\\gamma}-ray spectroscopy setup with the mono-energetic high-intensity photon beam of HI{\\gamma}S provides a worldwide unique experimental facility to investigate the {\\gamma}-decay pattern of dipole excitations in atomic nuclei. The performance of the new setup has been assessed by studying the nucleus \\sulfur at 8.125 MeV beam energy. The {\\gamma}-decay branching ratio from the $1^+$ level at 8125.4 keV to the first excited $2^+$ state was determined to 15.7(3)%.

Bastian Löher; Vera Derya; Thomas Aumann; Jacob Beller; Nathan Cooper; Marc Duchene; Janis Endres; Enrico Fiori; Johann Isaak; John Kelley; Michael Knörzer; Norbert Pietralla; Christopher Romig; Marcus Scheck; Heiko Scheit; Joel Silva; Anton P. Tonchev; Werner Tornow; Henry Weller; Volker Werner; Andreas Zilges

2013-04-23T23:59:59.000Z

408

Test and Evaluation of a High Efficiency Residential Fuel Cell System  

Science Conference Proceedings (OSTI)

A confluence of industry drivers, including the availability of low-cost natural gas, is creating new market opportunities for natural gas-based distributed generation. Solid oxide fuel cell systems (SOFC) are a potentially attractive option because of their high electrical efficiency (50–60% lower heating value (LHV)). This report documents two years of testing and evaluation of a 1.5 kW SOFC residential system provided by Ceramics Fuel Cell Limited. Tests were conducted in collaboration with ...

2013-12-20T23:59:59.000Z

409

Catalyst Additives to Enhance Mercury Oxidation and Capture  

SciTech Connect

Preliminary research has shown that SCR catalysts employed for nitrogen-oxide reduction can effectively oxidize mercury. Three different SCR catalysts are currently being studied in this project--honeycomb-type, plate-type, and a hybrid-type catalyst. The catalysts were manufactured and supplied by Cormetech Inc., Hitachi America Ltd., and Haldor-Topsoe Inc., respectively. Parametric testing was performed to investigate the contribution of flue-gas chemistry on mercury oxidation via SCR catalysts. Future work to characterize flue gas simulations typically derived from low and high sulfur bituminous coal are being performed in a stepwise manner, to avoid the constant interruptions in testing that occur when leaks in the system are generated during temperature transitions. Specifically, chlorine concentration vs. mercury oxidation correlations will be developed for each catalyst. The contributions of temperature are also being investigated. SO2 oxidation is also being investigated for each test condition.

Thomas K. Gale

2005-12-31T23:59:59.000Z

410

Catalyst Modeling and CLEERS - Emissions & Emission Controls...  

NLE Websites -- All DOE Office Websites (Extended Search)

Catalyst Modeling and CLEERS A large part of ORNL's efforts in catalyst research are geared toward model development of catalyst devices and engine systems. Experimental data...

411

Low cost, single crystal-like substrates for practical, high efficiency solar cells  

Science Conference Proceedings (OSTI)

It is well established that high efficiency (20%) solar cells can be routinely fabricated using single crystal photovoltaic (PV) materials with low defect densities. Polycrystalline materials with small grain sizes and no crystallographic texture typically result in reduced efficiences. This has been ascribed primarily to the presence of grain boundaries and their effect on recombination processes. Furthermore, lack of crystallographic texture can result in a large variation in dopant concentrations which critically control the electronic properties of the material. Hence in order to reproducibly fabricate high efficiency solar cells a method which results in near single crystal material is desirable. Bulk single crystal growth of PV materials is cumbersome, expensive and difficult to scale up. We present here a possible route to achieve this if epitaxial growth of photovoltaic materials on rolling-assisted-biaxially textured-substrates (RABiTS) can be achieved. The RABiTS process uses well-established, industrially scaleable, thermomechanical processing to produce a biaxially textured or single-crystal-like metal substrate with large grains (50-100 {mu}m). This is followed by epitaxial growth of suitable buffer layers to yield chemically and structurally compatible surfaces for epitaxial growth of device materials. Using the RABiTS process it should be possible to economically fabricate single-crystal-like substrates of desired sizes. Epitaxial growth of photovoltaic devices on such substrates presents a possible route to obtaining low-cost, high performance solar cells.

Goyal, A.; Specht, E.D.; List, F.A. [and others

1997-09-01T23:59:59.000Z

412

Cost Effective, High Efficiency Integrated Systems Approach to Auxilliary Electric Motors  

DOE Green Energy (OSTI)

The CARAT program, carried out by Kinetic Art & Technology Corporation (KAT), has been one of the most commercially successful KAT R&D programs to date. Based on previous development of its technology, KAT designed, constructed and tested a highly efficient motor and controller system under this CARAT program with supplemental commercial funding. Throughout this CARAT effort, the technical objectives have been refined and refocused. Some objectives have been greatly expanded, while others have been minimized. The determining factor in all decisions to refocus the objectives was the commercial need, primarily the needs of KAT manufacturing partners. Several companies are employing the resulting CARAT motor and controller designs in prototypes for commercial products. Two of these companies have committed to providing cost share in order to facilitate the development. One of these companies is a major manufacturing company developing a revolutionary new family of products requiring the ultra-high system efficiency achievable by the KAT motor and controller technologies (known as Segmented ElectroMagnetic Array, or SEMA technology). Another company requires the high efficiency, quiet operation, and control characteristics afforded by the same basic motor and controller for an advanced air filtration product. The combined annual production requirement projected by these two companies exceeds one million units by 2005.

Roy Kessinger Jr.; Keith Seymour; Kanchan Angal; Jason Wolf; Steve Brewer; Leonard Schrank

2003-09-26T23:59:59.000Z

413

Interfacial Engineering for Highly Efficient-Conjugated Polymer-Based Bulk Heterojunction Photovoltaic Devices  

Science Conference Proceedings (OSTI)

The aim of our proposal is to apply interface engineering approach to improve charge extraction, guide active layer morphology, improve materials compatibility, and ultimately allow the fabrication of high efficiency tandem cells. Specifically, we aim at developing: i. Interfacial engineering using small molecule self-assembled monolayers ii. Nanostructure engineering in OPVs using polymer brushes iii. Development of efficient light harvesting and high mobility materials for OPVs iv. Physical characterization of the nanostructured systems using electrostatic force microscopy, and conducting atomic force microscopy v. All-solution processed organic-based tandem cells using interfacial engineering to optimize the recombination layer currents vi. Theoretical modeling of charge transport in the active semiconducting layer The material development effort is guided by advanced computer modeling and surface/ interface engineering tools to allow us to obtain better understanding of the effect of electrode modifications on OPV performance for the investigation of more elaborate device structures. The materials and devices developed within this program represent a major conceptual advancement using an integrated approach combining rational molecular design, material, interface, process, and device engineering to achieve solar cells with high efficiency, stability, and the potential to be used for large-area roll-to-roll printing. This may create significant impact in lowering manufacturing cost of polymer solar cells for promoting clean renewable energy use and preventing the side effects from using fossil fuels to impact environment.

Alex Jen; David Ginger; Christine Luscombe; Hong Ma

2012-04-02T23:59:59.000Z

414

High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrator Application  

DOE Green Energy (OSTI)

The High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrators project seeks to provide new photovoltaic cells for Concentrator Photovoltaics (CPV) Systems with higher cell efficiency, more favorable temperature coefficients and less sensitivity to changes in spectral distribution. The main objective of this project is to provide high efficiency III-V solar cells that will reduce the overall cost per Watt for power generation using CPV systems.This work is focused both on a potential near term application, namely the use of indium arsenide (InAs) QDs to spectrally "tune" the middle (GaAs) cell of a SOA triple junction device to a more favorable effective bandgap, as well as the long term goal of demonstrating intermediate band solar cell effects. The QDs are confined within a high electric field i-region of a standard GaAs solar cell. The extended absorption spectrum (and thus enhanced short circuit current) of the QD solar cell results from the increase in the sub GaAs bandgap spectral response that is achievable as quantum dot layers are introduced into the i-region. We have grown InAs quantum dots by OMVPE technique and optimized the QD growth conditions. Arrays of up to 40 layers of strain balanced quantum dots have been experimentally demonstrated with good material quality, low residual stain and high PL intensity. Quantum dot enhanced solar cells were grown and tested under simulated one sun AM1.5 conditions. Concentrator solar cells have been grown and fabricated with 5-40 layers of QDs. Testing of these devices show the QD cells have improved efficiency compared to baseline devices without QDs. Device modeling and measurement of thermal properties were performed using Crosslight APSYS. Improvements in a triple junction solar cell with the insertion of QDs into the middle current limiting junction was shown to be as high as 29% under one sun illumination for a 10 layer stack QD enhanced triple junction solar cell. QD devices have strong potential for net gains in efficiency at high concentration.

Hubbard, Seth

2012-09-12T23:59:59.000Z

415

Advanced Alloys for Compact, High-Efficiency, High-Temperature Heat-Exchangers  

Science Conference Proceedings (OSTI)

Oak Ridge National Laboratory (ORNL) has conducted research and development for several years which has been focused on the behavior and performance improvements of sheets and foils of various alloys for compact heat-exchangers (recuperators) for advanced microturbines. The performance and reliability of such thin sections are challenged at 650-750 C by fine grain size causing excessive creep, and by moisture effects greatly enhancing oxidation attack in exhaust gas environments. Standard 347 stainless steel has been used successfully at or below 600 C, but has suffered from both of these kinds of degradation at 650 C and above. Alloys have been identified which can have very good properties for such heat-exchangers, especially with careful control of microstructure during processing, including alloy 625, HR120 and the new AL20-25+Nb. These alloys, and the mechanistic understanding behind their behavior, are also applicable to achieving the better heat-exchanger technology needed for fuel cells or other high-temperature, clean-energy applications.

Maziasz, Philip J [ORNL; Pint, Bruce A [ORNL; Shingledecker, John P [ORNL; Evans, Neal D [ORNL; Yamamoto, Yukinori [ORNL; More, Karren Leslie [ORNL; Lara-Curzio, Edgar [ORNL

2006-01-01T23:59:59.000Z

416

L&E: Adopt high-efficiency lighting for your parking lot | The Better  

NLE Websites -- All DOE Office Websites (Extended Search)

lot lot Activities Technology Solutions Teams Lighting & Electrical Space Conditioning Plug & Process Loads Food Service Refrigeration Laboratories Energy Management & Information Systems Public Sector Teams Market Solutions Teams Adopt high-efficiency lighting for your parking lot Most parking lots are illuminated by older high-intensity discharge (HID) lighting technology without any energy-saving controls. New light-emitting diode (LED) technology can cut parking lot lighting energy bills by 40%, or much more with controls, while delivering additional benefits including long life, reduced maintenance costs, and improved lighting uniformity. The Lighting & Electrical team developed a performance specification to help building owners take advantage of these improved lighting

417

Simulation of Device Parameters of High Efficiency Multicrystalline Silicon Solar Cells  

Science Conference Proceedings (OSTI)

The results of the simulation of the reported experimental results of high efficiency multicrystalline silicon (mc-Si) solar cells, using PC1D software, are reported in this study. Results obtained by various groups have been incorporated and compared in this study. The highest efficiency reported so far for mc-Si solar cells is 20{center_dot}4% and 17-18% by research laboratories and commercial houses, respectively. The efficiency can be further enhanced if passivation characteristics on both the front and back surface are improved. The role of back surface recombination has become more significant in light of the use of thin mc-Si wafers by the solar cell industry. Based on the passivation characteristics and considering the understanding of the past three decades of studies, the authors have proposed and simulated a structure for mc-Si solar cells to improve the performance of the same. The results of our modeled structure of mc-Si solar cell show an efficiency of 21{center_dot}88% with short-circuit current density, J{sub sc} = 39{center_dot}39 mA/cm2, and open circuit voltage, V{sub oc} = 0{center_dot}666 V.

Budhraja, V.; Misra, D.; Ravindra, N. M.

2011-11-01T23:59:59.000Z

418

Development of high efficiency (14%) solar cell array module. Final report, November 1979-June 1980  

DOE Green Energy (OSTI)

More effort was concentrated on development of procedures to provide large area (3 in. dia) high efficiency (16.5% AM1, 28/sup 0/C) P+NN+ solar cells. Intensive tests with 3 in. slices gave consistently lower efficiency (13.5%). The problems were identified as incomplete formation of an optimum back surface field (BSF), and interaction of the BSF process and the shallow P+ junction. The problem was shown not to be caused by reduced quality of silicon near the edges of the larger slices. A promising process sequence was identified. A reasonably large number of fairly efficient (13.5% average) 3 in. P+NN+ cells were made and combined with no problems with the module design developed for this project. In the module, one hundred and twenty (120) cells were connected, eight (8) in parallel and fifteen (15) in series. Six (6) modules were delivered with an average power output (per total module area of 6890 cm/sup 2/) of 75.3 watts and a module overall average efficiency of 10.9%.

Iles, P.A.; Khemthong, S.; Olah, S.; Sampson, W.J.; Ling, K.S.

1980-01-01T23:59:59.000Z

419

HIGH EFFICIENCY, LOW EMISSIONS, SOLID OXIDE FUEL CELL SYSTEMS FOR MULTIPLE APPLICATIONS  

DOE Green Energy (OSTI)

Technology Management Inc. (TMI), teamed with the Ohio Office of Energy Efficiency and Renewable Energy, has engineered, constructed, and demonstrated a stationary, low power, multi-module solid oxide fuel cell (SOFC) prototype system operating on propane and natural gas. Under Phase I, TMI successfully operated two systems in parallel, in conjunction with a single DC-AC inverter and battery bus, and produced net AC electricity. Phase II testing expanded to include alternative and renewable fuels typically available in rural regions of Ohio. The commercial system is expected to have ultra-low pollution, high efficiency, and low noise. The TMI SOFC uses a solid ceramic electrolyte operating at high temperature (800-1000 C) which electrochemically converts gaseous fuels (hydrogen or mixed gases) and oxygen into electricity. The TMI system design oxidizes fuel primarily via electrochemical reactions and uses no burners (which pollute and consume fuel)--resulting in extremely clean exhaust. The use of proprietary sulfur tolerant materials developed by TMI allows system operation without additional fuel pre-processing or sulfur removal. Further, the combination of high operating temperatures and solid state operation increases the potential for higher reliability and efficiencies compared to other types of fuel cells. Applications for the TMI SOFC system cover a wide range of transportation, building, industrial, and military market sectors. A generic technology, fuel cells have the potential to be embodied into multiple products specific to Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) program areas including: Fuel Cells and Microturbines, School Buildings, Transportation, and Bioenergy. This program focused on low power stationary applications using a multi-module system operating on a range of common fuels. By producing clean electricity more efficiently (thus using less fuel), fuel cells have the triple effect of cleaning up the environment, reducing the amount of fuel consumed and, for energy intensive manufacturers, boosting their profits (by reducing energy expenses). Compared to conventional power generation technologies such as internal combustion engines, gas turbines, and coal plants, fuel cells are extremely clean and more efficient, particularly at smaller scales.

Sara Ward; Michael A. Petrik

2004-07-28T23:59:59.000Z

420

High efficiency shale oil recovery. Final report, January 1, 1992--June 30, 1993  

SciTech Connect

The Adams Counter-current shale oil recovery process is an improved retorting technology enabling highly efficient oil recovery from oil shale. The high efficiency results primarily from the following facts: it (1) recovers the ash heat to preheat the feed ore; (2) burns and uses the coke energy and (3) operates without using hot ash recycling as a heat carrier. This latter feature is doubly important, contributing to high oil yield and to the generation of highly reactive coke which can be burned below 1000{degree}F, avoiding the endothermal calcination of the mineral carbonates and helping to clean the ash of contaminants. This project demonstrates that oil shale can be retorted under the specified conditions and achieve the objectives of very high efficiency. The project accomplished the following: 51 quartz sand rotary kiln runs provided significant engineering data. A heat transfer value of 107 Btu/hr/ft{sup 2}/{degree}F was obtained at optimum RPM; eight oil shale samples were obtained and preliminary shakedown runs were made. Five of the samples were selected for kiln processing and twelve pyrolysis runs were made on the five different oil shales;average off recovery was 109% of Fisher Assay; retorted residue from all five samples was oxidized at approximately 1000{degree}F. The ash from these runs was oxidized to varying extents, depending on the oil shale and oxidizing temperatures. While 1000{degree}F is adequately hot to provide process heat from coke combustion for these ores, some Eastern oil shales, without mineral carbonates, may be oxidized at higher temperatures, perhaps 100--300 degrees hotter, to obtain a more complete oxidation and utilization of the coke.

Adams, D.C.

1993-09-29T23:59:59.000Z

Note: This page contains sample records for the topic "highly efficient catalyst" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Design and development of a high-concentration and high-efficiency photovoltaic concentrator using a curved Fresnel lens  

DOE Green Energy (OSTI)

Thermo Electron has designed a high concentration photovoltaic module that uses a domed, point-focus Fresnel lens. Their design, design optimization process, and results from lens and receiver tests are described in this report. A complete module has not been fabricated and probably will not be fabricated in the future; however, Thermo Electron's optical design, analysis, and testing of both secondary optical units and domed Fresnel lenses have made a significant contribution to our project. Tooling errors prevented the lens from reaching its potential efficiency by the end of the contract, and resolution of these tooling problems is currently being attempted with a follow-on contract, No. 68-9463.

Scharlack, R.S.; Moffat, A.

1983-08-01T23:59:59.000Z

422

Improved anode catalysts for coal gas-fueled phosphoric acid fuel cells  

Science Conference Proceedings (OSTI)

The feasibility of adapting phosphoric acid fuel cells to operate on coal gas fuels containing significant levels of contaminants such as CO, H{sub 2}S and COS has been investigated. The overall goal was the development of low-cost, carbon-supported anode fuel cell catalysts that can efficiently operate with a fossil fuel-derived hydrogen gas feed contaminated with carbon monoxide and other impurities. This development would reduce the cost of gas cleanup necessary in a coal gas-fueled PAFC power plant, thereby reducing the final power cost of the electricity produced. The problem to date has been that the contaminant gases typically adsorb on catalytic sites and reduce the activity for hydrogen oxidation. An advanced approach investigated was to modify these alloy catalyst systems to operate efficiently on coal gas containing higher levels of contaminants by increasing the alloy catalyst impurity tolerance and ability to extract energy from the CO present through (1) generation of additional hydrogen by promoting the CO/H{sub 2} water shift reaction or (2) direct oxidation of CO to CO{sub 2} with the same result. For operation on anode gases containing high levels of CO, a Pt-Ti-Zn and Pt-Ti-Ni anode catalyst showed better performance over a Pt baseline or G87A-17-2 catalyst. The ultimate aim of this effort was to allow PAFC-based power plants to operate on coal gas fuels containing increased contaminant concentrations, thereby decreasing the need for and cost of rigorous coal gas cleanup procedures. 4 refs., 15 figs., 10 tabs.

Kackley, N.D.; McCatty, S.A.; Kosek, J.A.

1990-07-01T23:59:59.000Z

423

Recovery Act: Low-Cost, Highly Lambertian Reflector Composite For Improved LED Fixture Efficiency and Lifetime  

SciTech Connect

The overall objective of the program was to demonstrate a 98% or greater reflective, highly diffuse, low-cost composite material that significantly improves luminaire efficiency, is able to withstand 50,000 hours or greater luminaire operation under expected LED system thermal and environmental operating extremes and meets the cost targets required to be an effective commercial solution for the Solid State Lighting industry. This project met most of the goals defined and contributed to the understanding of high reflectance, white coatings. Research under this program increased the understanding of coatings development using particle size reduction techniques and preparation of coating solutions with a broad range of particle types. The research explored scale-up of coating systems and generated understanding of processing required for high volume manufacturing applications. The work demonstrated how coating formulation and application technique can translat