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Sample records for high efficiency heat

  1. High Efficiency Microturbine with Integral Heat Recovery - Presentatio...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency Microturbine with Integral Heat Recovery - Presentation by Capstone Turbine Corporation, June 2011 High Efficiency Microturbine with Integral Heat Recovery -...

  2. High Efficiency Microturbine with Integral Heat Recovery - Fact...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 Capstone Turbine...

  3. High Efficiency Microturbine with Integral Heat Recovery - Fact...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 High Efficiency Microturbine with Integral Heat Recovery - Fact Sheet, 2014 Capstone Turbine Corporation, in...

  4. High Efficiency Cold Climate Heat Pump

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh Efficiency Cold Climate

  5. High Efficiency Microturbine with Integral Heat Recovery

    SciTech Connect (OSTI)

    2010-10-01

    Fact sheet: this project will develop a clean, cost-effective 370 kW microturbine with 42% net electrical efficiency and 85% total CHP efficiency.

  6. High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power Generation High-Efficiency Quantum-Well Thermoelectrics for Waste Heat Power Generation 2005 Diesel Engine...

  7. Predicting high harmonic ion cyclotron heating efficiency in Tokamak plasmas

    SciTech Connect (OSTI)

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

    2011-01-01

    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.

  8. High Efficiency Microturbine with Integral Heat Recovery | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh EfficiencyEnergy

  9. High Efficiency Microturbine with Integral Heat Recovery- Fact Sheet, 2014

    Broader source: Energy.gov [DOE]

    Fact sheet: this project will develop a clean, cost-effective 370 kW microturbine with 42% net electrical efficiency and 85% total CHP efficiency

  10. High Efficiency Microturbine with Integral Heat Recovery- Presentation by Capstone Turbine Corporation, June 2011

    Broader source: Energy.gov [DOE]

    Presentation on High Efficiency Microturbine with Integral Heat Recovery, given by John Nourse of Capstone Turbine Corporation, at the U.S. DOE Industrial Distributed Energy Portfolio Review Meeting in Washington, D.C. on June 1-2, 2011.

  11. Simulation of a High Efficiency Multi-bed Adsorption Heat Pump

    SciTech Connect (OSTI)

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

    2012-05-01

    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.

  12. High Efficiency R-744 Commercial Heat Pump Water Heaters

    SciTech Connect (OSTI)

    Elbel, Dr. Stefan W.; Petersen, Michael

    2013-04-25

    The project investigated the development and improvement process of a R744 (CO2) commercial heat pump water heater (HPWH) package of approximately 35 kW. The improvement process covered all main components of the system. More specific the heat exchangers (Internal heat exchanger, Evaporator, Gas cooler) as well as the expansion device and the compressor were investigated. In addition, a comparison to a commercially available baseline R134a unit of the same capacity and footprint was made in order to compare performance as well as package size reduction potential.

  13. High-Efficiency Commercial Cold Climate Heat Pump

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡HighApproachesDepartment

  14. High-Efficiency Commercial Cold Climate Heat Pump

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡HighApproachesDepartment ofEngines

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

    E-Print Network [OSTI]

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

    2013-01-01

    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.

  16. Electrical heating of soils using high efficiency electrode patterns and power phases

    DOE Patents [OSTI]

    Buettner, Harley M. (Livermore, CA)

    1999-01-01

    Powerline-frequency electrical (joule) heating of soils using a high efficiency electrode configuration and power phase arrangement. The electrode configuration consists of several heating or current injection electrodes around the periphery of a volume of soil to be heated, all electrodes being connected to one phase of a multi-phase or a single-phase power system, and a return or extraction electrode or electrodes located inside the volume to be heated being connected to the remaining phases of the multi-phase power system or to the neutral side of the single-phase power source. This electrode configuration and power phase arrangement can be utilized anywhere where powerline frequency soil heating is applicable and thus has many potential uses including removal of volatile organic compounds such as gasoline and tricholorethylene (TCE) from contaminated areas.

  17. Development of High Efficiency Carbon Dioxide Commercial Heat Pump Water Heater

    SciTech Connect (OSTI)

    Michael PETERSEN; Chad D. BOWERS; Stefan ELBEL; Pega HRNJAK

    2012-07-01

    Although heat pump water heaters are today widely accepted in both Japan and Europe, where energy costs are high and government incentives for their use exist, acceptance of such products in the US has been limited. While this trend is slowly changing with the introduction of heat pump water heaters into the residential market, but acceptance remains low in the commercial sector. The objective of the presented work is the development of a high efficiency R744 heat pump water heater for commercial applications with effective utilization of the cooling capability for air conditioning and/or refrigeration. The ultimate goal is to achieve total system COP of up to 8. This unit will be targeted at commercial use where some cooling load is typically needed year round, such as restaurants, hotels, nursing homes, and hospitals. This paper presents the performance results from the development of four R744 commercial heat pump water heater packages of approximately 35 kW and comparison to a commercially available baseline R134a unit of the same capacity and footprint. In addition, the influences of an internal heat exchanger and an enhanced evaporator on the system performance are described and recommendations are made for further improvements of the R744 system.

  18. Efficient Heat Storage Materials: Metallic Composites Phase-Change Materials for High-Temperature Thermal Energy Storage

    SciTech Connect (OSTI)

    2011-11-21

    HEATS Project: MIT is developing efficient heat storage materials for use in solar and nuclear power plants. Heat storage materials are critical to the energy storage process. In solar thermal storage systems, heat can be stored in these materials during the day and released at nightwhen the suns not outto drive a turbine and produce electricity. In nuclear storage systems, heat can be stored in these materials at night and released to produce electricity during daytime peak-demand hours. MIT is designing nanostructured heat storage materials that can store a large amount of heat per unit mass and volume. To do this, MIT is using phase change materials, which absorb a large amount of latent heat to melt from solid to liquid. MITs heat storage materials are designed to melt at high temperatures and conduct heat wellthis makes them efficient at storing and releasing heat and enhances the overall efficiency of the thermal storage and energy-generation process. MITs low-cost heat storage materials also have a long life cycle, which further enhances their efficiency.

  19. Candidate alloys for cost-effective, high-efficiency, high-temperature compact/foil heat-exchangers

    SciTech Connect (OSTI)

    Evans, Neal D; Maziasz, Philip J; Shingledecker, John P; Pint, Bruce A; Yamamoto, Yukinori

    2007-01-01

    Solid oxide fuel cell (SOFC) and molten carbonate fuel cell (MCFC) systems operate at high temperatures (up to 1000 C and 650 C, respectively), which makes them especially attractive sources for combined heat and power (CHP) cogeneration. However, improvements in the efficiency of heat exchange in these fuel cells require both development and careful processing of advanced cost-effective alloys for use in such high-temperature service conditions. The high-temperature properties of both sheet and foil forms of several alloys being considered for use in compact heat-exchangers (recuperators) have been characterized. Mechanical and creep-rupture testing, oxidation studies, and microstructural studies have been performed on commercially available sheet and foil forms of alloy 347, alloys 625, HR230, HR120, and the new AL20-25+Nb. These studies have led to a mechanistic understanding of the responses of these alloys to anticipated service conditions, and suggest that these alloys developed for gas- and micro-turbine recuperator applications are also suitable for use in fuel cell heat-exchangers. Additional work is still required to achieve foil forms with creep life comparable to thicker-section wrought product forms of the same alloys.

  20. A physically-based heat pump model was connected to an optimization program to form a computer code for use in the design of high-efficiency

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;ABSTRACT A physically-based heat pump model was connected to an optimization program to form a computer code for use in the design of high-efficiency heat pumps. The method used allows efficiency of conventional heat pumps, ten variables were optimized while heating capacity was fixed

  1. Development and Demonstration of a High Efficiency, Rapid Heating, Low NOx Alternative to Conventional Heating of Round Steel Shapes, Steel Substrate (Strip) and Coil Box Transfer Bars

    SciTech Connect (OSTI)

    Kurek, Harry; Wagner, John

    2010-01-25

    Direct Flame Impingement involves the use of an array of very high-velocity flame jets impinging on a work piece to rapidly heat the work piece. The predominant mode of heat transfer is convection. Because of the locally high rate of heat transfer at the surface of the work piece, the refractory walls and exhaust gases of a DFI furnace are significantly cooler than in conventional radiant heating furnaces, resulting in high thermal efficiency and low NOx emissions. A DFI furnace is composed of a successive arrangement of heating modules through or by which the work piece is conveyed, and can be configured for square, round, flat, and curved metal shapes (e.g., billets, tubes, flat bars, and coiled bars) in single- or multi-stranded applications.

  2. Demonstration and Performance Monitoring of Foundation Heat Exchangers (FHX) in Ultra-High Energy Efficient Research Homes

    SciTech Connect (OSTI)

    Im, Piljae; Hughes, Patrick; Liu, Xiaobing

    2012-01-01

    The more widespread use of Ground Source Heat Pump (GSHP) systems has been hindered by their high first cost, which is mainly driven by the cost of the drilling and excavation for installation of ground heat exchangers (GHXs). A new foundation heat exchanger (FHX) technology was proposed to reduce first cost by placing the heat exchanger into the excavations made during the course of construction (e.g., the overcut for the basement and/or foundation and run-outs for water supply and the septic field). Since they reduce or eliminate the need for additional drilling or excavation, foundation heat exchangers have the potential to significantly reduce or eliminate the first cost premium associated with GSHPs. Since December 2009, this FHX technology has been demonstrated in two ultra-high energy efficient new research houses in the Tennessee Valley, and the performance data has been closely monitored as well. This paper introduces the FHX technology with the design, construction and demonstration of the FHX and presents performance monitoring results of the FHX after one year of monitoring. The performance monitoring includes hourly maximum and minimum entering water temperature (EWT) in the FHX compared with the typical design range, temperature difference (i.e., T) across the FHX, and hourly heat transfer rate to/from the surrounding soil.

  3. High Efficiency 370kW Microturbine with Integral Heat Recovery

    Broader source: Energy.gov (indexed) [DOE]

    Design a small turbine power generation system with the following: 42% Engine Efficiency 85% Total System Efficiency with CHP 2007 CARB-level emissions without...

  4. Large-dimension, high-ZT Thermoelectric Nanocomposites for High-Power High-efficiency Waste Heat Recovery for Electricity Generation

    Broader source: Energy.gov [DOE]

    Large-dimension, high-ZT BiTe and Pb-based nanocomposites produced with a low-cost scalable process were used for development and testing of TE module prototypes, and demonstration of a waste heat recovery system

  5. High Efficiency Solid-State Heat Pump Module | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh

  6. Heat Pump for High School Heat Recovery

    E-Print Network [OSTI]

    Huang, K.; Wang, H.; Zhou, X.

    2006-01-01

    The heat pump system used for recycling and reusing waste heat in s high school bathroom was minutely analyzed in its coefficient of performance, onetime utilization ratio of energy, economic property and so on. The results showed that this system...

  7. Thermodynamic Efficiency of Heat Exchange Devices

    E-Print Network [OSTI]

    Witte, L. C.; Shamsundar, N.

    1982-01-01

    inlet temperatures, the efficiency and effectiveness for particular heat exchange configurations are related. Conclusions regarding the effect of stream temperatures on the efficiency of various types of exchangers are made. The concept is applied...

  8. Promising Technology: High-Efficiency Rooftop Units

    Broader source: Energy.gov [DOE]

    High-efficiency rooftop air conditioning units (RTUs) can significantly reduce heating, cooling, and ventilation energy consumption. High efficiency RTUs incorporate variable speed controls to minimize fan and compressor energy while capturing and reusing heat, cold, and humidity from a buildings exhaust air.

  9. High Efficiency Integrated Space Conditioning, Water Heating and Air Distribution System for HUD-Code Manufactured Housing

    SciTech Connect (OSTI)

    Henry DeLima; Joe Akin; Joseph Pietsch

    2008-09-14

    Recognizing the need for new space conditioning and water heating systems for manufactured housing, DeLima Associates assembled a team to develop a space conditioning system that would enhance comfort conditions while also reducing energy usage at the systems level. The product, Comboflair® was defined as a result of a needs analysis of project sponsors and industry stakeholders. An integrated system would be developed that would combine a packaged airconditioning system with a small-duct, high-velocity air distribution system. In its basic configuration, the source for space heating would be a gas water heater. The complete system would be installed at the manufactured home factory and would require no site installation work at the homesite as is now required with conventional split-system air conditioners. Several prototypes were fabricated and tested before a field test unit was completed in October 2005. The Comboflair® system, complete with ductwork, was installed in a 1,984 square feet, double-wide manufactured home built by Palm Harbor Homes in Austin, TX. After the home was transported and installed at a Palm Harbor dealer lot in Austin, TX, a data acquisition system was installed for remote data collection. Over 60 parameters were continuously monitored and measurements were transmitted to a remote site every 15 minutes for performance analysis. The Comboflair® system was field tested from February 2006 until April 2007. The cooling system performed in accordance with the design specifications. The heating system initially could not provide the needed capacity at peak heating conditions until the water heater was replaced with a higher capacity standard water heater. All system comfort goals were then met. As a result of field testing, we have identified improvements to be made to specific components for incorporation into production models. The Comboflair® system will be manufactured by Unico, Inc. at their new production facility in St. Louis, MO. The product will be initially launched in the hot-humid climates of the southern U.S.

  10. Field Test of High Efficiency Residential Buildings with Ground-source and Air-source Heat Pump Systems

    SciTech Connect (OSTI)

    Ally, Moonis Raza [ORNL] [ORNL; Munk, Jeffrey D [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL

    2011-01-01

    This paper describes the field performance of space conditioning and water heating equipment in four single-family residential structures with advanced thermal envelopes. Each structure features a different, advanced thermal envelope design: structural insulated panel (SIP); optimum value framing (OVF); insulation with embedded phase change materials (PCM) for thermal storage; and exterior insulation finish system (EIFS). Three of the homes feature ground-source heat pumps (GSHPs) for space conditioning and water heating while the fourth has a two-capacity air-source heat pump (ASHP) and a heat pump water heater (HPWH). Two of the GCHP-equipped homes feature horizontal ground heat exchange (GHX) loops that utillize the existing foundation and utility service trenches while the third features a vertical borehole with vertical u-tube GHX. All of the houses were operated under the same simulated occupancy conditions. Operational data on the house HVAC/Water heating (WH) systems are presented and factors influencing overall performance are summarized.

  11. Estimating Costs and Efficiency of Storage, Demand, and Heat...

    Energy Savers [EERE]

    Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters A water heater's energy...

  12. Energy Efficient HVAC System for Distributed Cooling/Heating...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficient HVAC System for Distributed CoolingHeating with Thermoelectric Devices Energy Efficient HVAC System for Distributed CoolingHeating with Thermoelectric Devices 2012 DOE...

  13. Ultra Efficient Combined Heat, Hydrogen, and Power System - Presentati...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ultra Efficient Combined Heat, Hydrogen, and Power System - Presentation by FuelCell Energy, June 2011 Ultra Efficient Combined Heat, Hydrogen, and Power System - Presentation by...

  14. Estimating Costs and Efficiency of Storage, Demand, and Heat...

    Office of Environmental Management (EM)

    Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters A water heater's...

  15. Estimating Costs and Efficiency of Storage, Demand, and Heat...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters Estimating Costs and Efficiency of Storage, Demand, and Heat Pump Water Heaters March 10, 2015 -...

  16. PECO Energy (Gas)- Heating Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    The PECO Smart Natural Gas Efficiency Upgrade Program offers rebates and incentives to commercial or residential customers that install an ENERGY STAR qualified high-efficiency natural gas furna...

  17. High Efficiency Engine Technologies Program

    SciTech Connect (OSTI)

    Rich Kruiswyk

    2010-07-13

    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.

  18. Application of Industrial Heat Improving energy efficiency of

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Application of Industrial Heat Pumps Improving energy efficiency of industrial processes . H Session Application of Industrial Heat Pumps Improving energy efficiency of industrial processes Agency (IEA) - Agreements "Heat Pump Programme" "Industrial Energy-related Technologies and Systems #12

  19. Vehicle Technologies Office Merit Review 2014: Nanostructured High-Temperature Bulk Thermoelectric Energy Conversion for Efficient Waste Heat Recovery

    Broader source: Energy.gov [DOE]

    Presentation given by GMZ Energy Inc. at 2014 DOE Hydrogen and Fuel Cells Program and Vehicle Technologies Office Annual Merit Review and Peer Evaluation Meeting about nanostructured high...

  20. High efficiency incandescent lighting

    DOE Patents [OSTI]

    Bermel, Peter; Ilic, Ognjen; Chan, Walker R.; Musabeyoglu, Ahmet; Cukierman, Aviv Ruben; Harradon, Michael Robert; Celanovic, Ivan; Soljacic, Marin

    2014-09-02

    Incandescent lighting structure. The structure includes a thermal emitter that can, but does not have to, include a first photonic crystal on its surface to tailor thermal emission coupled to, in a high-view-factor geometry, a second photonic filter selected to reflect infrared radiation back to the emitter while passing visible light. This structure is highly efficient as compared to standard incandescent light bulbs.

  1. High Efficiency, Clean Combustion

    SciTech Connect (OSTI)

    Donald Stanton

    2010-03-31

    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

  2. ELECTRIC CO-HEATING: A METHOD FOR EVALUATING SEASONAL HEATING EFFICIENCIES AND HEAT LOSS RATES IN DWELLINGS

    E-Print Network [OSTI]

    Modera, M.P.

    2012-01-01

    the measured values for heat transmission and air leakagethe contribution by heat transmission alone through theheating efficiency, heat transmission coefficient and air

  3. Waste Heat Reduction and Recovery for Improving Furnace Efficiency...

    Broader source: Energy.gov (indexed) [DOE]

    Waste Heat Reduction and Recovery for Improving Furnace Efficiency, Productivity and Emissions Performance: A BestPractices Process Heating Technical Brief (November 2004) More...

  4. Computationally Efficient Modeling of High-Efficiency Clean Combustion...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    & Publications Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines Computationally Efficient Modeling of High-Efficiency Clean Combustion Engines...

  5. Estimating Costs and Efficiency of Storage, Demand, and Heat...

    Broader source: Energy.gov (indexed) [DOE]

    have a higher purchase price. Determining Energy Efficiency of Storage, Demand, and Heat Pump Water Heaters Use the energy factor to determine the energy efficiency of a storage,...

  6. Industrial Energy Efficiency and Combined Heat and Power Fact Sheet

    SciTech Connect (OSTI)

    Industrial Energy Efficiency and Combined Heat and Power Working Group

    2012-07-16

    Provides an overview of the State and Local Energy Efficiency Action Network's (SEE Action) Industrial Energy Efficiency and Combined Heat and Power Working Group.

  7. Future EfficientDynamics with Heat Recovery | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    EfficientDynamics with Heat Recovery Future EfficientDynamics with Heat Recovery A 15% increase in engine performance could be demonstrated with a Dual-Loop-Rankine and 10%...

  8. High Efficiency Room Air Conditioner

    SciTech Connect (OSTI)

    Bansal, Pradeep

    2015-01-01

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However, all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.

  9. HIGH EFFICIENCY SYNGAS GENERATION

    SciTech Connect (OSTI)

    Robert J. Copeland; Yevgenia Gershanovich; Brian Windecker

    2005-02-01

    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.

  10. Joule heating at high latitudes

    SciTech Connect (OSTI)

    Foster, J.C.; St.-Maurice, J.; Abreu, V.J.

    1983-06-01

    High latitude Joule heating has been calculated from simultaneous observations of the electric field magnitude and the Pedersen conductivity calculated from individual measurements of the ion drift velocity and particle precipitation observed over the lifetime of the AE-C satellite. The data were sorted by latitude, local time, hemisphere, season, and Kp index and separate averages of the electric field magnitude, Pedersen conductivity and Joule heating was prepared. Conductivities produced by an averaged seasonal solar illumination were included with those calculated from the particle precipitation. We found that high-latitude Joule heating occurs in a roughly oval pattern and consists of three distinct heating regions: the dayside cleft, the region of sunward convection at dawn and dusk, and the midnight sector. On the average, heating in the cleft and dawn-dusk regions contributes the largest heat input. There is no apparent difference between hemispheres for similar seasons. Hemisphere averaged Joule heating at equinox amounts to approximately 25 GW for Kp = 1 conditions, 85G GW for Kp = 4, and varies linearly as a function of Kp. The Joule heat input is 50% greater during the summer than during winter primarily due to the increased conductivity caused by solar production.

  11. High efficiency Brayton cycles using LNG

    DOE Patents [OSTI]

    Morrow, Charles W. (Albuquerque, NM)

    2006-04-18

    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.

  12. High Efficiency Integrated Package

    SciTech Connect (OSTI)

    Ibbetson, James

    2013-09-15

    Solid-state lighting based on LEDs has emerged as a superior alternative to inefficient conventional lighting, particularly incandescent. LED lighting can lead to 80 percent energy savings; can last 50,000 hours 2-50 times longer than most bulbs; and contains no toxic lead or mercury. However, to enable mass adoption, particularly at the consumer level, the cost of LED luminaires must be reduced by an order of magnitude while achieving superior efficiency, light quality and lifetime. To become viable, energy-efficient replacement solutions must deliver system efficacies of ? 100 lumens per watt (LPW) with excellent color rendering (CRI > 85) at a cost that enables payback cycles of two years or less for commercial applications. This development will enable significant site energy savings as it targets commercial and retail lighting applications that are most sensitive to the lifetime operating costs with their extended operating hours per day. If costs are reduced substantially, dramatic energy savings can be realized by replacing incandescent lighting in the residential market as well. In light of these challenges, Cree proposed to develop a multi-chip integrated LED package with an output of > 1000 lumens of warm white light operating at an efficacy of at least 128 LPW with a CRI > 85. This product will serve as the light engine for replacement lamps and luminaires. At the end of the proposed program, this integrated package was to be used in a proof-of-concept lamp prototype to demonstrate the components viability in a common form factor. During this project Cree SBTC developed an efficient, compact warm-white LED package with an integrated remote color down-converter. Via a combination of intensive optical, electrical, and thermal optimization, a package design was obtained that met nearly all project goals. This package emitted 1295 lm under instant-on, room-temperature testing conditions, with an efficacy of 128.4 lm/W at a color temperature of ~2873K and 83 CRI. As such, the packages performance exceeds DOEs warm-white phosphor LED efficacy target for 2013. At the end of the program, we assembled an A19 sized demonstration bulb housing the integrated package which met Energy Star intensity variation requirements. With further development to reduce overall component cost, we anticipate that an integrated remote converter package such as developed during this program will find application in compact, high-efficacy LED-based lamps, particularly those requiring omnidirectional emission.

  13. Geothermal Heat Pumps are Scoring High Marks

    SciTech Connect (OSTI)

    2000-08-01

    Geothermal Energy Program Office of Geothermal and Wind Technologies Geothermal Heat Pumps are Scoring High Marks Geothermal heat pumps, one of the clean energy technology stars Geothermal heat pumps (GHPs) are one of the most cost-effective heating, cooling, and water heating systems available for both residential and commercial buildings. GHPs extract heat from the ground during the heating season and discharge waste heat to the ground during the cooling season. The U.S. Environmental Protecti

  14. Heat exchanger efficiently operable alternatively as evaporator or condenser

    DOE Patents [OSTI]

    Ecker, Amir L. (Dallas, TX)

    1981-01-01

    A heat exchanger adapted for efficient operation alternatively as evaporator or condenser and characterized by flexible outer tube having a plurality of inner conduits and check valves sealingly disposed within the outer tube and connected with respective inlet and outlet master flow conduits and configured so as to define a parallel flow path for a first fluid such as a refrigerant when flowed in one direction and to define a serpentine and series flow path for the first fluid when flowed in the opposite direction. The flexible outer tube has a heat exchange fluid, such as water, flowed therethrough by way of suitable inlet and outlet connections. The inner conduits and check valves form a package that is twistable so as to define a spiral annular flow path within the flexible outer tube for the heat exchange fluid. The inner conduits have thin walls of highly efficient heat transfer material for transferring heat between the first and second fluids. Also disclosed are specific materials and configurations.

  15. Ecological and Economical efficient Heating and Cooling by innovative Gas Motor Heat Pump Systems and Solutions

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;Ecological and Economical efficient Heating and Cooling by innovative Gas Motor Heat Pump use of buildings Gas Heat Pump Solution #12;Gas Heat Pump - deserves special attention due to its source in addition to the outside air A further essential component of Gas Heat Pump air conditioning

  16. The efficiency of diabatic heating and tropical cyclone intensification

    E-Print Network [OSTI]

    Smith, Roger K.

    The efficiency of diabatic heating and tropical cyclone intensification Roger K. Smitha and Michael cyclones to the increasing "efficiency" of diabatic heating in the cyclone's inner core region associated with deep convection. The efficiency, in essence the amount of temperature warming compared to the amount

  17. High Efficient Natural Gas Technologies

    Broader source: Energy.gov (indexed) [DOE]

    by: Eric Burgis Energy Solutions Center 610-796-1946 eburgis@escenter.org High Efficient Natural Gas Technologies FUPWG 5814 2 Energy Solutions Center Inc. - All Rights...

  18. Experimental study of a high efficiency gyrotron oscillator

    E-Print Network [OSTI]

    Choi, Eunmi, Ph. D. Massachusetts Institute of Technology

    2007-01-01

    High power, high frequency gyrotrons used in plasma heating must achieve the highest possible efficiency in order to reduce system size and cost and to minimize thermal and mechanical problems. This thesis presents an ...

  19. Minimum Efficiency Requirements Tables for Heating and Cooling...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    (FEMP) created tables that mirror American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 90.1-2013 tables, which include minimum efficiency...

  20. Residential Multi-Function Gas Heat Pump: Efficient Engine-Driven...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Residential Multi-Function Gas Heat Pump: Efficient Engine-Driven Heat Pump for the Residential Sector - Fact Sheet, 2013 Residential Multi-Function Gas Heat Pump: Efficient...

  1. High efficiency, radiation-hard solar cells

    E-Print Network [OSTI]

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

    2004-01-01

    Igari, and W. Warta, Solar Cell Efficiency Tables (Version56326 High efficiency, radiation-hard solar cells Finalprototype high efficiency multijunction (MJ) solar cells use

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

    Broader source: Energy.gov [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...

  3. High efficiency novel window air conditioner

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Bansal, Pradeep

    2015-07-24

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, andmoreR410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.less

  4. High efficiency novel window air conditioner

    SciTech Connect (OSTI)

    Bansal, Pradeep

    2015-07-24

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and R410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.

  5. Heating, Ventilation and Air Conditioning Efficiency

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    outside pump circulating heat transfer fluid air make-up inside exhaust 24 Cogged V Belts A major N.C. Manufacturer Tested 2-17 Months (yr 1985) .052KWH (.13 EP) 2700 Hours...

  6. Secondary heat exchanger design and comparison for advanced high temperature reactor

    SciTech Connect (OSTI)

    Sabharwall, P.; Kim, E. S.; Siahpush, A.; McKellar, M.; Patterson, M.

    2012-07-01

    Next generation nuclear reactors such as the advanced high temperature reactor (AHTR) are designed to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. This study considers two different types of heat exchangers - helical coiled heat exchanger and printed circuit heat exchanger - as possible options for the AHTR secondary heat exchangers with distributed load analysis and comparison. Comparison is provided for all different cases along with challenges and recommendations. (authors)

  7. High efficiency and high concentration in photovoltaics

    SciTech Connect (OSTI)

    Yamaguchi, Masafumi; Luque, A.

    1999-10-01

    In this paper, the authors present the state-of-the-art of multijunction solar cells and the future prospects of this technology. Their use in terrestrial applications will likely be for concentrators operating at very high concentrations. Some trends are also discussed and the authors present a cost calculation showing that highly efficient cells under very high concentration would be able to produce electricity at costs competitive with electricity generation costs for some utilities.

  8. Ultra Efficient Combined Heat, Hydrogen, and Power System

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ultra Efficient Combined Heat, Hydrogen, and Power System DE-EE0003679 FuelCell Energy, Inc. 1012010 - 9302011 Pinakin Patel FuelCell Energy Inc. ppatel@fce.com 203-825-6072...

  9. Union Power Cooperative- Residential Energy Efficient Heat Pump Loan Program

    Broader source: Energy.gov [DOE]

    Union Power Cooperative offers low interest loans to help its qualifying residential customers finance new, energy-efficient heat pumps. Interest rates, currently at 9%, will be fixed for the term...

  10. Energy efficiency in building sector in India through Heat

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;Energy efficiency in building sector in India through Heat Pump Technology By Mr Pradeep Kumar sector in India Residential building sector in India HVAC growth in residential sector. Heat Pump, Sustainable habitat, Biotechnology, Renewable energy, Water technology, Industrial research, Social

  11. "Tuning" microalgae for high photosynthesis efficiency

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    "Tuning" Microalgae For High Photosynthesis Efficiency "Tuning" microalgae for high photosynthesis efficiency Los Alamos scientist Richard Sayre and his team of researchers have...

  12. High-Efficiency Solar Cogeneration with Thermophotovoltaic &...

    Office of Environmental Management (EM)

    High-Efficiency Solar Cogeneration with Thermophotovoltaic & Fiber-Optic Daylighting High-Efficiency Solar Cogeneration with Thermophotovoltaic & Fiber-Optic Daylighting Credit:...

  13. Energy Efficiency Supporting Policy and Heat Pumping Technology in Japan

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    conservation 4 Feature ( Newly developed) Design for CO2 refrigerant Compressor for high pressure Counter flow Heat exchanger Over 15 manufactures have taken part in the markets ever since. Owing to newly developed feature Counter flow Heat exchanger Heat pump unit Storage tank Ref: TEPCO Website Ref: HPTCJ HP Space

  14. Ultra Efficient Combined Heat, Hydrogen, and Power System

    SciTech Connect (OSTI)

    2010-10-28

    Description of CHHP system which utilizes a high-temperature fuel cell to provide on-site process reducing gas, clean power, and heat.

  15. Ultra Efficient Combined Heat, Hydrogen, and Power System - Fact...

    Broader source: Energy.gov (indexed) [DOE]

    Inc., in collaboration with Abbott Furnace Company, is developing a combined heat, hydrogen, and power (CHHP) system that utilizes reducing gas produced by a high-temperature...

  16. Heating, Ventilation and Air Conditioning Efficiency

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢ £Space Heating

  17. High Heat Flux Thermoelectric Module Using Standard Bulk Material...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat Flux Thermoelectric Module Using Standard Bulk Material High Heat Flux Thermoelectric Module Using Standard Bulk Material Presents high heat flux thermoelectric module design...

  18. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    Technology Roadmap. Energy-efficient Buildings: Heating andenergy-efficient approaches to thermal comfort using room air motion. Building

  19. Optimal Efficiency of Heat Engines with Finite-Size Heat Baths

    E-Print Network [OSTI]

    Hiroyasu Tajima; Masahito Hayashi

    2015-09-29

    The optimal efficiency of quantum (or classical) heat engines whose heat baths are $n$-particle systems is given by the information geometry and the strong large deviation. We give the optimal work extraction process as a concrete energy-preserving unitary time evolution among the heat baths and the work storage. We show that our optimal work extraction turns the disordered energy of the heat baths to the ordered energy of the work storage, by evaluating the ratio of the entropy difference to the energy difference in the heat baths and the work storage, respectively. By comparing the statistical machanical optimal efficiency with the macroscopic thermodynamical bound, we evaluate the accuracy of the macroscopic thermodynamics with finite-size heat baths from the statistical mechanical viewpoint.

  20. Development of a High Efficiency Hot Gas Turbo-expander and Low...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    a High Efficiency Hot Gas Turbo-expander and Low Cost Heat Exchangers for Optimized CSP Supercritical CO2 Operation Development of a High Efficiency Hot Gas Turbo-expander and...

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

    E-Print Network [OSTI]

    ). TPVs present an extremely appealing approach for small-scale power sources due to the combination-high-energy-density, high-efficiency, and small-scale portable power generation is addressed here using a distinctive- thermophotovoltaic (TPV) generator. The approach is predicted to be capable of up to 32% efficient heat

  2. Secondary Heat Exchanger Design and Comparison for Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Ali Siahpush; Michael McKellar; Michael Patterson; Eung Soo Kim

    2012-06-01

    The goals of next generation nuclear reactors, such as the high temperature gas-cooled reactor and advance high temperature reactor (AHTR), are to increase energy efficiency in the production of electricity and provide high temperature heat for industrial processes. The efficient transfer of energy for industrial applications depends on the ability to incorporate effective heat exchangers between the nuclear heat transport system and the industrial process heat transport system. The need for efficiency, compactness, and safety challenge the boundaries of existing heat exchanger technology, giving rise to the following study. Various studies have been performed in attempts to update the secondary heat exchanger that is downstream of the primary heat exchanger, mostly because its performance is strongly tied to the ability to employ more efficient conversion cycles, such as the Rankine super critical and subcritical cycles. This study considers two different types of heat exchangershelical coiled heat exchanger and printed circuit heat exchangeras possible options for the AHTR secondary heat exchangers with the following three different options: (1) A single heat exchanger transfers all the heat (3,400 MW(t)) from the intermediate heat transfer loop to the power conversion system or process plants; (2) Two heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants, each exchanger transfers 1,700 MW(t) with a parallel configuration; and (3) Three heat exchangers share heat to transfer total heat of 3,400 MW(t) from the intermediate heat transfer loop to the power conversion system or process plants. Each heat exchanger transfers 1,130 MW(t) with a parallel configuration. A preliminary cost comparison will be provided for all different cases along with challenges and recommendations.

  3. Condensing Heat Exchanger for Optimization of Energy Efficiency

    E-Print Network [OSTI]

    Carrigan, J. F.; Johnson, D. W.; DiVitto, J. G.; Schulze, K. H.

    1995-01-01

    Historically, boiler efficiency has been limited due to the minimum temperature allowed at the stack. Heat lost up the stack was in exchange for keeping the flue gas temperature above the water vapor dew point. If water vapor was allowed to condense...

  4. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    Technology Roadmap. Energy-efficient Buildings: Heating andH, Zhai Y. Enabling energy-efficient approaches to thermalEnergy-efficient comfort with a heated/cooled chair: results

  5. High-efficiency photovoltaic cells

    DOE Patents [OSTI]

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

    1982-06-21

    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.

  6. New configurations of a heat recovery absorption heat pump integrated with a natural gas boiler for boiler efficiency improvement

    SciTech Connect (OSTI)

    Qu, Ming; Abdelaziz, Omar; Yin, Hongxi

    2014-11-01

    Conventional natural gas-fired boilers exhaust flue gas direct to the atmosphere at 150 200 C, which, at such temperatures, contains large amount of energy and results in relatively low thermal efficiency ranging from 70% to 80%. Although condensing boilers for recovering the heat in the flue gas have been developed over the past 40 years, their present market share is still less than 25%. The major reason for this relatively slow acceptance is the limited improvement in the thermal efficiency of condensing boilers. In the condensing boiler, the temperature of the hot water return at the range of 50 60 C, which is used to cool the flue gas, is very close to the dew point of the water vapor in the flue gas. Therefore, the latent heat, the majority of the waste heat in the flue gas, which is contained in the water vapor, cannot be recovered. This paper presents a new approach to improve boiler thermal efficiency by integrating absorption heat pumps with natural gas boilers for waste heat recovery (HRAHP). Three configurations of HRAHPs are introduced and discussed. The three configurations are modeled in detail to illustrate the significant thermal efficiency improvement they attain. Further, for conceptual proof and validation, an existing hot water-driven absorption chiller is operated as a heat pump at operating conditions similar to one of the devised configurations. An overall system performance and economic analysis are provided for decision-making and as evidence of the potential benefits. These three configurations of HRAHP provide a pathway to achieving realistic high-efficiency natural gas boilers for applications with process fluid return temperatures higher than or close to the dew point of the water vapor in the flue gas.

  7. Liquid metal heat exchanger for efficient heating of soils and geologic formations

    DOE Patents [OSTI]

    DeVault, Robert C. (Knoxville, TN) [Knoxville, TN; Wesolowski, David J. (Kingston, TN) [Kingston, TN

    2010-02-23

    Apparatus for efficient heating of subterranean earth includes a well-casing that has an inner wall and an outer wall. A heater is disposed within the inner wall and is operable within a preselected operating temperature range. A heat transfer metal is disposed within the outer wall and without the inner wall, and is characterized by a melting point temperature lower than the preselected operating temperature range and a boiling point temperature higher than the preselected operating temperature range.

  8. Theoretical Design of a Thermosyphon for Efficient Process Heat Removal from Next Generation Nuclear Plant (NGNP) for Production of Hydrogen

    SciTech Connect (OSTI)

    Piyush Sabharwall; Fred Gunnerson; Akira Tokuhiro; Vivek Utgiker; Kevan Weaver; Steven Sherman

    2007-10-01

    The work reported here is the preliminary analysis of two-phase Thermosyphon heat transfer performance with various alkali metals. Thermosyphon is a device for transporting heat from one point to another with quite extraordinary properties. Heat transport occurs via evaporation and condensation, and the heat transport fluid is re-circulated by gravitational force. With this mode of heat transfer, the thermosyphon has the capability to transport heat at high rates over appreciable distances, virtually isothermally and without any requirement for external pumping devices. For process heat, intermediate heat exchangers (IHX) are required to transfer heat from the NGNP to the hydrogen plant in the most efficient way possible. The production of power at higher efficiency using Brayton Cycle, and hydrogen production requires both heat at higher temperatures (up to 1000oC) and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. The purpose for selecting a compact heat exchanger is to maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. The IHX design requirements are governed by the allowable temperature drop between the outlet of the NGNP (900oC, based on the current capabilities of NGNP), and the temperatures in the hydrogen production plant. Spiral Heat Exchangers (SHEs) have superior heat transfer characteristics, and are less susceptible to fouling. Further, heat losses to surroundings are minimized because of its compact configuration. SHEs have never been examined for phase-change heat transfer applications. The research presented provides useful information for thermosyphon design and Spiral Heat Exchanger.

  9. Cedarville Elementary & High School Space Heating Low Temperature...

    Open Energy Info (EERE)

    Cedarville Elementary & High School Space Heating Low Temperature Geothermal Facility Jump to: navigation, search Name Cedarville Elementary & High School Space Heating Low...

  10. Modular Low Cost High Energy Exhaust Heat Thermoelectric Generator...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low Cost High Energy Exhaust Heat Thermoelectric Generator with Closed-Loop Exhaust By-Pass System Modular Low Cost High Energy Exhaust Heat Thermoelectric Generator with...

  11. High Operating Temperature Heat Transfer Fluids for Solar Thermal...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Operating Temperature Heat Transfer Fluids for Solar Thermal Power Generation FY13 Q1 High Operating Temperature Heat Transfer Fluids for Solar Thermal Power Generation FY13...

  12. Advanced Review High efficiency photovoltaics: on

    E-Print Network [OSTI]

    Delaware, University of

    price and its relation to market electricity sales price. The current gap between PV energy price the research and development opportunities for high-efficiency PV and projects the required efficiency-priceAdvanced Review High efficiency photovoltaics: on the way to becoming a major electricity source

  13. High Efficiency Fans and High Efficiency Electrical Motors

    E-Print Network [OSTI]

    Breedlove, C. W.

    1989-01-01

    operates from 800 hours to 1500 hours per year or 15% of the year. Sixty percent of the connected horsepower is operating pneumatic air fans. These pneumatic fans transport the seed cotton, cotton lint, cottonseed and cotton trash throughout... efficiency will be consistent and ongoing. Since pneumat cs use 60% of the total power consumed in a cotton gin it seemed the most likely pace to improve efficiency. Each fan's sys em was redesigned and engineered. Not on y were old inefficient fans...

  14. On the maximum efficiency of realistic heat engines

    E-Print Network [OSTI]

    E. N. Miranda

    2012-08-10

    In 1975, Courzon and Ahlborn studied a Carnot engine with thermal losses and got an expression for its efficiency that described better the performance of actual heat machines than the traditional result due to Carnot. In their original derivation, time appears explicitly and this is disappointing in the framework of classical thermodynamics. In this note a derivation is given without any explicit reference to time.

  15. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, B.D.; Ward, M.E.

    1998-09-22

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures. 5 figs.

  16. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

    1998-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a strengthening reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the strengthening reinforcing member. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  17. High pressure ceramic heat exchanger

    DOE Patents [OSTI]

    Harkins, Bruce D. (San Diego, CA); Ward, Michael E. (Poway, CA)

    1999-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present header assembly when used with recuperators reduces the brittle effect of a portion of the ceramic components. Thus, the present header assembly used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present header assembly is comprised of a first ceramic member, a second ceramic member, a reinforcing member being in spaced relationship to the first ceramic member and the second ceramic member. The header assembly is further comprised of a refractory material disposed in contacting relationship with the first ceramic member, the second ceramic member and the reinforcing member and having a strengthening member wrapped around the refractory material. The present header assembly provides a high strength load bearing header assembly having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  18. Very low temperature radiant heating/cooling indoor end system for efficient use of renewable energies

    SciTech Connect (OSTI)

    Ren, Jianbo; Wang, Yiping; Wang, Congrong; Xiong, Weicheng; Zhu, Li

    2010-06-15

    Solar or solar-assisted space heating systems are becoming more and more popular. The solar energy utilization efficiency is high when the collector is coupled with indoor radiant heating suppliers, since in principle, lower supply temperature means lower demand temperature and then the system heat loss is less. A new type radiant end system is put forward for even lower supply temperature compared to the conventional radiant floor heating systems. A three dimensional model was established to investigate its energy supply capacities. Simulation results show that 50 W per meter length tube can be achieved with the medium temperature of 30 C for heating and 15 C for cooling. The predicted results agree well with the actual data from a demonstration building. Furthermore, it is demonstrated that a supply temperature of 22 C in winter and of 17 C in summer already met the indoor requirements. The new end system has good prospects for effective use of local renewable resources. (author)

  19. Technology Development for High Efficiency Clean Diesel Engines...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency Clean Diesel Engines and a Pathway to 50% Thermal Efficiency Technology Development for High Efficiency Clean Diesel Engines and a Pathway to 50% Thermal Efficiency...

  20. High efficiency turbine blade coatings.

    SciTech Connect (OSTI)

    Youchison, Dennis L.; Gallis, Michail A.

    2014-06-01

    The development of advanced thermal barrier coatings (TBCs) of yttria stabilized zirconia (YSZ) that exhibit lower thermal conductivity through better control of electron beam - physical vapor deposition (EB-PVD) processing is of prime interest to both the aerospace and power industries. This report summarizes the work performed under a two-year Lab-Directed Research and Development (LDRD) project (38664) to produce lower thermal conductivity, graded-layer thermal barrier coatings for turbine blades in an effort to increase the efficiency of high temperature gas turbines. This project was sponsored by the Nuclear Fuel Cycle Investment Area. Therefore, particular importance was given to the processing of the large blades required for industrial gas turbines proposed for use in the Brayton cycle of nuclear plants powered by high temperature gas-cooled reactors (HTGRs). During this modest (~1 full-time equivalent (FTE)) project, the processing technology was developed to create graded TBCs by coupling ion beam-assisted deposition (IBAD) with substrate pivoting in the alumina-YSZ system. The Electron Beam - 1200 kW (EB-1200) PVD system was used to deposit a variety of TBC coatings with micron layered microstructures and reduced thermal conductivity below 1.5 W/m.K. The use of IBAD produced fully stoichiometric coatings at a reduced substrate temperature of 600 oC and a reduced oxygen background pressure of 0.1 Pa. IBAD was also used to successfully demonstrate the transitioning of amorphous PVD-deposited alumina to the -phase alumina required as an oxygen diffusion barrier and for good adhesion to the substrate Ni2Al3 bondcoat. This process replaces the time consuming thermally grown oxide formation required before the YSZ deposition. In addition to the process technology, Direct Simulation Monte Carlo plume modeling and spectroscopic characterization of the PVD plumes were performed. The project consisted of five tasks. These included the production of layered periodic microstructures in the coating, the Direct Simulation Monte Carlo (DSMC) modeling of particle transport in the PVD plume, functional graded layer development, the deposition of all layers to form a complete coating, and materials characterization including thermal testing. Ion beam-assisted deposition, beam sharing through advanced digital rastering, substrate pivoting, hearth calorimetry, infrared imaging, fiber optic-enabled optical emission spectroscopy and careful thermal management were used to achieve all the milestones outlined in the FY02 LDRD proposal.

  1. Highly Efficient Coherent Raman Generation

    E-Print Network [OSTI]

    Hua, Xia

    2014-08-04

    explore detection and sensing applications, and achieve further improvement of efficiency by using field enhancement due to surface plasmon resonances in aggregates of gold nanoparticles. By scanning the time delay of the probe pulse, we demonstrate a new...

  2. High Energy Efficiency Air Conditioning

    SciTech Connect (OSTI)

    Edward McCullough; Patrick Dhooge; Jonathan Nimitz

    2003-12-31

    This project determined the performance of a new high efficiency refrigerant, Ikon B, in a residential air conditioner designed to use R-22. The refrigerant R-22, used in residential and small commercial air conditioners, is being phased out of production in developed countries beginning this year because of concerns regarding its ozone depletion potential. Although a replacement refrigerant, R-410A, is available, it operates at much higher pressure than R-22 and requires new equipment. R-22 air conditioners will continue to be in use for many years to come. Air conditioning is a large part of expensive summer peak power use in many parts of the U.S. Previous testing and computer simulations of Ikon B indicated that it would have 20 - 25% higher coefficient of performance (COP, the amount of cooling obtained per energy used) than R-22 in an air-cooled air conditioner. In this project, a typical new R-22 residential air conditioner was obtained, installed in a large environmental chamber, instrumented, and run both with its original charge of R-22 and then with Ikon B. In the environmental chamber, controlled temperature and humidity could be maintained to obtain repeatable and comparable energy use results. Tests with Ikon B included runs with and without a power controller, and an extended run for several months with subsequent analyses to check compatibility of Ikon B with the air conditioner materials and lubricant. Baseline energy use of the air conditioner with its original R-22 charge was measured at 90 deg F and 100 deg F. After changeover to Ikon B and a larger expansion orifice, energy use was measured at 90 deg F and 100 deg F. Ikon B proved to have about 19% higher COP at 90 deg F and about 26% higher COP at 100 deg F versus R-22. Ikon B had about 20% lower cooling capacity at 90 deg F and about 17% lower cooling capacity at 100 deg F versus R-22 in this system. All results over multiple runs were within 1% relative standard deviation (RSD). All of these values agree well with previous results and computer simulations of Ikon B performance versus R-22. The lower cooling capacity of Ikon B is not a concern unless a particular air conditioner is near its maximum cooling capacity in application. Typically, oversized A/C systems are installed by contractors to cover contingencies. In the extended run with Ikon B, which lasted about 4.5 months at 100 deg F ambient temperature and 68% compressor on time, the air conditioner performed well with no significant loss of energy efficiency. Post-run analysis of the refrigerant, compressor lubricant oil, compressor, compressor outlet tubing, and the filter/dryer showed minor effects but nothing that was considered significant. The project was very successful. All objectives were achieved, and the performance of Ikon B indicates that it can easily be retrofitted into R-22 air conditioners to give 15 - 20% energy savings and a 1 - 3 year payback of retrofit costs depending on location and use. Ikon B has the potential to be a successful commercial product.

  3. Increasing LTC Engine Efficiency by Reducing Pressure-Oscillation-Related Heat Transfer Losses

    Broader source: Energy.gov [DOE]

    This research discusses how reducing heat-transfer losses from pressure oscillation can increase low-temperature combustion engine efficiency.

  4. NREL's Building-Integrated Supercomputer Provides Heating and Efficient Computing (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2014-09-01

    NREL's Energy Systems Integration Facility (ESIF) is meant to investigate new ways to integrate energy sources so they work together efficiently, and one of the key tools to that investigation, a new supercomputer, is itself a prime example of energy systems integration. NREL teamed with Hewlett-Packard (HP) and Intel to develop the innovative warm-water, liquid-cooled Peregrine supercomputer, which not only operates efficiently but also serves as the primary source of building heat for ESIF offices and laboratories. This innovative high-performance computer (HPC) can perform more than a quadrillion calculations per second as part of the world's most energy-efficient HPC data center.

  5. High Efficiency Fuel Reactivity Controlled Compression Ignition...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency Fuel Reactivity Controlled Compression Ignition Combustion An optimized dual-fuel PCCI concept, RCCI, is proposed. deer10reitz.pdf More Documents & Publications...

  6. Webinar: Highly Efficient Solar Thermochemical Reaction Systems

    Broader source: Energy.gov [DOE]

    Video recording and text version of the Fuel Cell Technologies Office webinar titled "Highly Efficient Solar Thermochemical Reaction Systems," originally presented on January 13, 2015.

  7. Nanostructured Thermoelectric Materials and High Efficiency Power...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Nanostructured Thermoelectric Materials and High Efficiency Power Generation Modules Home Author: T. Hogan, A. Downey, J. Short, S. D. Mahanti, H. Schock, E. Case Year: 2007...

  8. High Efficiency Modular Chemical Processes (HEMCP)

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    - ADVANCED MANUFACTURING OFFICE High Efficiency Modular Chemical Processes (HEMCP) Modular Process Intensification Framework for R&D Targets Advanced Manufacturing Office...

  9. Energy Efficient Process Heating: Managing Air Flow Kevin Carpenter and Kelly Kissock

    E-Print Network [OSTI]

    Kissock, Kelly

    Energy Efficient Process Heating: Managing Air Flow Kevin Carpenter and Kelly Kissock Department important aspect to consider when attempting to improve the energy efficiency of most process heating. Infiltration air enters the system through openings in the system shell. For energy- efficient process heating

  10. Efficiency improvement of a ground coupled heat pump system from energy management

    E-Print Network [OSTI]

    Fernndez de Crdoba, Pedro

    Efficiency improvement of a ground coupled heat pump system from energy management N. Pardo a,*, coupled heat pump Energy efficiency Numerical simulation a b s t r a c t The installed capacity of an air to improve the efficiency of a ground coupled heat pump air conditioning system by adapting its produced

  11. NREL Documents Efficiency of Mini-Split Heat Pumps (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-06-01

    A new report delivers mini-split heat pump (MSHP) performance data for use in whole-building simulation tools. Mini-split heat pumps (MSHPs) are highly efficient refrigerant-based air conditioning and heating systems that permit room-by-room conditioning and control in homes. Because of their size, efficiency, and price, MSHPs are very popular overseas and are gaining market share in energy-efficient home upgrades in the United States. They are a good option for retrofitting older homes that lack ductwork. To evaluate MSHP cost effectiveness and performance in U.S. homes, National Renewable Energy Laboratory (NREL) researchers are studying these systems in the laboratory, simulated buildings, and field test settings. A new NREL report describes an innovative laboratory approach to testing MSHPs and includes experimental performance maps for use in whole-building simulation tools. Most public information on MSHP performance is provided by equipment manufacturers, and is typically limited to performance at a single operating speed for heating and cooling. Mini-split heat pumps use variable speed components that spin up and down to continuously meet the heating or cooling need, significantly improving a system's operating efficiency. Measuring that efficiency in a laboratory is challenging and required new approaches to performance testing. NREL researchers worked with colleagues at Purdue University's Herrick Labs and Ecotope, Inc. to refine and apply this new approach to a suite of MSHP products. Researchers measured the performance of two MSHPs across a variety of operating conditions, which allowed, for the first time, development of accurate building simulation MSHP models. In the laboratory tests, researchers found that both MSHPs achieved manufacturer-reported performance at rating conditions. However, at other temperature and humidity conditions, the heat pumps capacity ranged from 40% above to 54% below the manufacturer-reported values. Knowing how performance varies is critical in order to reasonably estimate annual energy consumption of a MSHP, and to compare MSHPs to other heating and cooling options. Mini-split heat pump efficiency (COP) was seen to significantly exceed rated efficiency at low compressor speeds-a very important effect.

  12. High Efficiency Electron-Laser Interactions in Tapered Helical Undulators

    E-Print Network [OSTI]

    Duris, Joseph

    2015-01-01

    Demonstration of high-trapping efficiency and narrow energylaser accelerator for efficient production of high qualityand J. S. Wurtele. High-efficiency extraction of microwave

  13. Path to High Efficiency Gasoline Engine | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Path to High Efficiency Gasoline Engine Path to High Efficiency Gasoline Engine Path to High Efficiency Gasoline Engine deer10johansson.pdf More Documents & Publications Partially...

  14. High Efficiency Broadband Envelope-Tracking Power Amplifiers

    E-Print Network [OSTI]

    Yan, Jonmei Johana

    M. , Wideband High Efficiency Envelope Tracking PowerPeter M. , High-Efficiency Envelope Tracking High PowerMemory! DPD! Drain! Efficiency! (%)! Gain! (dB)! Output!

  15. Promotion of efficient heat pumps for heating (ProHeatPump)

    E-Print Network [OSTI]

    and lessons. 2 Norway's energy sector 2.1.1 Norway is rich in hydropower, oil, gas, and forests for biofuel.1-intensive industries that depend on cheap electricity. Oil use has decreased since 1976. Biofuel use is small. But the proportion of those renting has increased since 1999, particularly in urban areas. 2.3.2 Heating represents

  16. Ultra-Compact High-Efficiency Luminaire for General Illumination

    SciTech Connect (OSTI)

    Ted Lowes

    2012-04-08

    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 today??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 ? 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.

  17. White LED with High Package Extraction Efficiency

    SciTech Connect (OSTI)

    Yi Zheng; Matthew Stough

    2008-09-30

    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.

  18. USING LIGA BASED MICROFABRICATION TO IMPROVE OVERALL HEAT TRANSFER EFFICIENCY OF PRESSURIZED WATER REACTOR: I. Effects of Different Micro Pattern on Overall Heat Transfer.

    SciTech Connect (OSTI)

    Zhang, M.; Ibekwe, S.; Li, G.; Pang, S.S.; and Lian, K.

    2006-07-01

    The Pressurized Water Reactors (PWRs in Figure 1) were originally developed for naval propulsion purposes, and then adapted to land-based applications. It has three parts: the reactor coolant system, the steam generator and the condenser. The Steam generator (a yellow area in Figure 1) is a shell and tube heat exchanger with high-pressure primary water passing through the tube side and lower pressure secondary feed water as well as steam passing through the shell side. Therefore, a key issue in increasing the efficiency of heat exchanger is to improve the design of steam generator, which is directly translated into economic benefits. The past research works show that the presence of a pin-fin array in a channel enhances the heat transfer significantly. Hence, using microfabrication techniques, such as LIGA, micro-molding or electroplating, some special microstructures can be fabricated around the tubes in the heat exchanger to increase the heat-exchanging efficiency and reduce the overall size of the heat-exchanger for the given heat transfer rates. In this paper, micro-pin fins of different densities made of SU-8 photoresist are fabricated and studied to evaluate overall heat transfer efficiency. The results show that there is an optimized micro pin-fin configuration that has the best overall heat transfer effects.

  19. Influence of Transfer Efficiency of the Outdoor Pipe Network and Boiler Operating Efficiency on the Building Heat Consumption Index

    E-Print Network [OSTI]

    Fang, X.; Wang, Z.; Liu, H.

    2006-01-01

    This paper analyzes the influence of transfer efficiency of the outdoor pipe network and operating efficiency of the boiler on the building heat consumption index, on the premise of saving up to 65 percent energy in different climates. The results...

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

    SciTech Connect (OSTI)

    2012-01-11

    HEATS Project: Abengoa Solar is developing a high-efficiency solar-electric conversion tower to enable low-cost, fully dispatchable solar energy generation. Abengoas 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.

  1. IEA Heat Pump Conference 2011, 16 -19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    00149 -1- 10th IEA Heat Pump Conference 2011, 16 - 19 May 2011, Tokyo, Japan ENERGY EFFICIENT AIR TO AIR HEAT PUMP OPERATING WITH R-1234yf Sorina Mortada, Ph.D. student, Center for Energy and Processes Abstract: Significant improvements in energy performance of air-to-air heat pumps are the major reason

  2. Thermal Strategies for High Efficiency Thermoelectric Power Generation...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Strategies for High Efficiency Thermoelectric Power Generation Thermal Strategies for High Efficiency Thermoelectric Power Generation Developing integrated TE system configurations...

  3. HIGH-POWER, HIGH-EFFICIENCY FELS

    E-Print Network [OSTI]

    Sessler, A.M.

    2008-01-01

    M. Kumada, "Scaling of the FEL-ID Equations", ELF Note 128,Instability in a High-power, Short- Wavelength FEL", Proc.of the Ninth FEL" Conference, Williamsburg (1988), and

  4. Technology Development for Light Duty High Efficient Diesel Engines...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Light Duty High Efficient Diesel Engines Technology Development for Light Duty High Efficient Diesel Engines Improve the efficiency of diesel engines for light duty applications...

  5. Efficient high density train operations

    DOE Patents [OSTI]

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

    2001-01-01

    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.

  6. Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock

    E-Print Network [OSTI]

    Kissock, Kelly

    1 Energy Efficient Process Heating: Insulation and Thermal Mass Kevin Carpenter and Kelly Kissock tanks and reducing thermal mass. A companion paper, Energy Efficiency Process Heating: Managing Air Flow of the oven/furnace. Reducing the quantity of energy lost to thermal mass in a process heating system saves

  7. Efficiency, Economic and Environmental Assessment of Ground-Source Heat Pumps in

    E-Print Network [OSTI]

    Blumsack, Seth

    1 Efficiency, Economic and Environmental Assessment of Ground-Source Heat Pumps in Central pump (GSP) for heating, cooling and hot water in a Central Pennsylvania residence (namely, the author, the efficiency gain for the ground-source heat pump compared to electricity is 43% for cooling and 81

  8. Webinar: Highly Efficient Solar Thermochemical Reaction Systems

    Broader source: Energy.gov [DOE]

    The Fuel Cell Technologies Office will present a live webinar titled "Highly Efficient Solar Thermochemical Reaction Systems" on Tuesday, January 13, from 12:00 to 1:00 p.m. Eastern Standard Time.

  9. Highly Efficient Solar Thermochemical Reaction Systems

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Highly Efficient, Solar Thermochemical Reaction Systems (2014 R&D 100 Award Winner) U.S. Department of Energy Fuel Cell Technologies Office 2 Question and Answer * Please type your...

  10. Efficiency of Brownian heat engines Imre Derenyi and R. Dean Astumian

    E-Print Network [OSTI]

    Dernyi, Imre

    Efficiency of Brownian heat engines Imre Derenyi and R. Dean Astumian Department of Surgery, MC 1999 We study the efficiency of one-dimensional thermally driven Brownian ratchets or heat engines. We there is no fundamental limit of the efficiency lower than that of a Carnot cycle. S1063-651X 99 50106-2 PACS number

  11. Multicolor, High Efficiency, Nanotextured LEDs

    SciTech Connect (OSTI)

    Jung Han; Arto Nurmikko

    2011-09-30

    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.

  12. Energy Efficient Design of a Waste Heat Rejection System

    E-Print Network [OSTI]

    Mehta, P.

    2000-01-01

    , and oil preheaters. The heating requirements for these heat sinks are generally met by burning fossil fuels or even by using electric heaters while available waste heat is rejected to the surrounding environment using devices such as cooling towers...

  13. An Analysis of Efficiency Improvements in Residential Sized Heat Pumps

    E-Print Network [OSTI]

    O'Neal, D. L.; Boecker, C. L.; Murphy, W. E.; Notman, J. R.

    1986-01-01

    The objectives of this study included: (1) development of classes of heat pumps, (2) evaluation and selection of a suitable heat pump design model, (3) characterization of suitable baseline heat pump designs, (4) selection of design options that can...

  14. Waste Heat Reduction and Recovery for Improving Furnace Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    gas heat losses can be calculated by the equation: Furnace exhaust heat losses W * Cp * (T exhaust - T ambient) Where: * W Mass of the exhaust gases * Cp Specific heat of...

  15. DESIGN OF A COMPACT HEAT EXCHANGER FOR HEAT RECUPERATION FROM A HIGH TEMPERATURE ELECTROLYSIS SYSTEM

    SciTech Connect (OSTI)

    G. K. Housley; J.E. O'Brien; G.L. Hawkes

    2008-11-01

    Design details of a compact heat exchanger and supporting hardware for heat recuperation in a high-temperature electrolysis application are presented. The recuperative heat exchanger uses a vacuum-brazed plate-fin design and operates between 300 and 800C. It includes corrugated inserts for enhancement of heat transfer coefficients and extended heat transfer surface area. Two recuperative heat exchangers are required per each four-stack electrolysis module. The heat exchangers are mated to a base manifold unit that distributes the inlet and outlet flows to and from the four electrolysis stacks. Results of heat exchanger design calculations and assembly details are also presented.

  16. Incorporate Minimum Efficiency Requirements for Heating and Cooling...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    about FEMP-designated and ENERGY STAR-qualified heating, ventilating, and air conditioning (HVAC) and water heating products into tables that mirror American Society of...

  17. Numerical study of high heat ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b

    E-Print Network [OSTI]

    Maruyama, Shigeo

    Numerical study of high heat ux pool boiling heat transfer Ying He a,*, Masahiro Shoji b , Shigeo simulation model of boiling heat transfer is proposed based on a numerical macrolayer model [S. Maruyama, M. Shoji, S. Shimizu, A numerical simulation of transition boiling heat transfer, in: Proceedings

  18. High Efficiency Full Expansion (FEx) Engine for Automotive Applications

    Broader source: Energy.gov [DOE]

    Large increases in engine thermal efficiency result from a new method of large reductions in both heat energy normally lost to the cooling medium and in heat energy in the exhaust system.

  19. DEVELOPMENT OF A HIGH PERFORMANCE COLD CLIMATE HEAT PUMP

    SciTech Connect (OSTI)

    Horton, W. Travis; Groll, Eckhard A.; Braun, James E.

    2014-06-01

    The primary goals of the proposed project were to develop, test, and evaluate a high performance and cost-effective vapor compression air-source heat pump for use in cold climate regions. Vapor compression heat pumps are a proven technology, and have been used for many years to meet heating requirements for buildings in residential, commercial, and industrial applications. However, in climate regions that experience very low outdoor ambient temperatures both the heating capacity and coefficient of performance (COP) of traditional air-source vapor compression heat pumps drops dramatically with a decrease in the outdoor air temperature. The efficiency of heat pumping equipment has improved substantially over the past 20 years; however, the efficiencies of the highest rated equipment on the market are approaching practical limits that cannot be surpassed without modifications to the basic cycle and possibly the use of additional hardware. In this report, three technologies to improve the efficiency of vapor compression systems are described. These are a) vapor injected compression, b) oil flooded compression and c) hybrid flow control of the evaporator. Compressor prototypes for both, oil flooded and vapor injected compression were developed by Emerson Climate Technologies. For the oil flooded compressor, the oil injection port location was optimized and an internal oil separator was added using several design iterations. After initial testing at Emerson Climate Technologies, further testing was done at Purdue University, and compressor models were developed. These models were then integrated into a system model to determine the achievable improvement of seasonal energy efficiency (SEER) for Minneapolis (Minnesota) climate. For the oil flooded compression, a 34% improvement in seasonal energy efficiency was found while a 21% improvement in seasonal energy efficiency ratio was found for the vapor injected compression. It was found that one benefit of both tested compression technologies is a lower discharge temperature, which allows for continued operation at lower ambient temperatures. A bin analysis of the vapor injected prototype cold climate heat pump predicts a 6% improvement in HSPF for Minneapolis. This improvement is mainly a result of the increased capacity of the system for active vapor injection. For the oil flooded system, a slightly larger performance improvement is predicted, in this case mostly caused by an increase in heating COP. Based on an economic analysis of these results, the maximum additional cost of the system changes, for the Minneapolis location, are $430 for the vapor injected system and $391 for the oil flooded system. These estimates assume that a 3-year simple payback period is accepted by the customer. For the hybrid flow control of evaporators, a new type of balancing valve was developed together with Emerson Climate technologies to reduce the cost of the control scheme. In contrast to conventional stepper motor valves, this valve requires less cables and can be driven by a cheaper output circuit on the control board. The correct valve size was determined in a dedicated test stand in several design iterations. The performance benefits of the hybrid control of the evaporator coil were determined for clean coil conditions as well as with partial blockage of the air inlet grille and under frosting conditions. For clean coil conditions, the benefits in terms of COP and capacity are negligible. However, significant benefits were noted for severely air-maldistributed operating conditions. For the H2-test, the maximum COP improvement of 17% along with a capacity improvement of nearly 40% was observed. Overall, the hybrid control scheme leads to a significant amount of performance improvement, if the air inlet conditions to the evaporator are maldistributed.

  20. High-Efficiency Inverter for Photovoltaic Applications

    E-Print Network [OSTI]

    Perreault, Dave

    , photovoltaic power systems, AC module. I. INTRODUCTION A. Motivation and Background The market for roof and associated con- trol method suitable for high efficiency DC to AC grid-tied power conversion. This approach) applications. The topology is based on a series resonant inverter, a high frequency transformer, and a novel

  1. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    dual compressor available on the market Compared with the selected building, a more energy efficient building will have lower space cooling and heating

  2. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    supported by the California Energy Commission (CEC)Public Interest Energy Research (PIER) Buildings ProgramIEA. Technology Roadmap. Energy-efficient Buildings: Heating

  3. An electrochemical system for efficiently harvesting low-grade heat energy

    E-Print Network [OSTI]

    Lee, Seok Woo

    Efficient and low-cost thermal energy-harvesting systems are needed to utilize the tremendous low-grade heat sources. Although thermoelectric devices are attractive, its efficiency is limited by the relatively low ...

  4. Comparison of the high temperature heat flux sensor to traditional heat flux gages under high heat flux conditions.

    SciTech Connect (OSTI)

    Blanchat, Thomas K.; Hanks, Charles R.

    2013-04-01

    Four types of heat flux gages (Gardon, Schmidt-Boelter, Directional Flame Temperature, and High Temperature Heat Flux Sensor) were assessed and compared under flux conditions ranging between 100-1000 kW/m2, such as those seen in hydrocarbon fire or propellant fire conditions. Short duration step and pulse boundary conditions were imposed using a six-panel cylindrical array of high-temperature tungsten lamps. Overall, agreement between all gages was acceptable for the pulse tests and also for the step tests. However, repeated tests with the HTHFS with relatively long durations at temperatures approaching 1000%C2%B0C showed a substantial decrease (10-25%) in heat flux subsequent to the initial test, likely due to the mounting technique. New HTHFS gages have been ordered to allow additional tests to determine the cause of the flux reduction.

  5. High-Efficiency Absorber for Damping the Transverse Wake Fields

    SciTech Connect (OSTI)

    Novokhatski, A.; Seeman, J.; Weathersby, S.; /SLAC

    2007-02-28

    Transverse wake fields generated by intense beams may propagate long distances in the vacuum chamber and dissipate power in different shielded elements such as bellows, vacuum valves or vacuum pumps. Induced heating in these elements may be high enough to deteriorate vacuum conditions. We have developed a broadband water-cooled bellows-absorber to capture and damp these harmful transverse fields without impacting the longitudinal beam impedance. Experimental results at the PEP-II SLAC B-factory demonstrate high efficiency of this device. This absorber may be useful in other machines like synchrotron light sources or International Linear Collider.

  6. The maximum efficiency of nano heat engines depends on more than temperature

    E-Print Network [OSTI]

    Mischa P. Woods; Nelly Ng; Stephanie Wehner

    2015-06-07

    Sadi Carnot's theorem regarding the maximum efficiency of heat engines is considered to be of fundamental importance in the theory of heat engines and thermodynamics. Here, we show that at the nano and quantum scale, this law needs to be revised in the sense that more information about the bath other than its temperature is required to decide whether maximum efficiency can be achieved. In particular, we derive new fundamental limitations of the efficiency of heat engines at the nano and quantum scale that show that the Carnot efficiency can only be achieved under special circumstances, and we derive a new maximum efficiency for others.

  7. High flux heat transfer in a target environment

    E-Print Network [OSTI]

    McDonald, Kirk

    Valid for: Consider turbulent heat transfer in a 1.5mm diameter pipe Dittus Boelter correlationHigh flux heat transfer in a target environment T. Davenne High Power Targets Group Rutherford Radiation Cooling Forced Convection Nucleate Boiling Critical Heat Flux Other ideas Summary #12

  8. Measure Guideline: High Efficiency Natural Gas Furnaces

    SciTech Connect (OSTI)

    Brand, L.; Rose, W.

    2012-10-01

    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.

  9. Using Plate Heat Exchangers to Increase Energy Efficiency

    E-Print Network [OSTI]

    Bailey, K.

    1999-01-01

    "In recent years, there has been an increasing awareness of Plate Heat Exchangers (PHE's) in industrial processes around the world. While PHE's have historically been classified as compact heat exchangers, compactness is often a secondary advantage...

  10. Efficient Engine-Driven Heat Pump for the Residential Sector

    Broader source: Energy.gov [DOE]

    Building on previous work on an 11-ton packaged natural gas heat pump, this project will develop hardware and software for engine and system controls for a residential gas heat pump system that...

  11. NOTES AND DISCUSSIONS Note on thermal heating efficiency

    E-Print Network [OSTI]

    Rodriguez, Carlos

    DERIVATION We have a source of heat Q2 which is available at Kelvin temperature T2 . By this we mean, as was stressed long ago by Gibbs,4 that the source is capable of delivering that heat to a heat reservoir which. This is the conversion problem faced in every home, where one has heat from a gas, oil, wood, or coal flame but wants

  12. High efficiency switching-mode amplifiers for wireless communication systems

    E-Print Network [OSTI]

    Hung, Tsai-Pi

    2008-01-01

    M. Asbeck, Design of high-efficiency current-mode class-Dand G. Rabjohn, A high efficiency Chireix Out- phasingE-A new class of high efficiency tuned single-ended power

  13. Heat exchanger with transpired, highly porous fins

    DOE Patents [OSTI]

    Kutscher, Charles F. (Golden, CO); Gawlik, Keith (Boulder, CO)

    2002-01-01

    The heat exchanger includes a fin and tube assembly with increased heat transfer surface area positioned within a hollow chamber of a housing to provide effective heat transfer between a gas flowing within the hollow chamber and a fluid flowing in the fin and tube assembly. A fan is included to force a gas, such as air, to flow through the hollow chamber and through the fin and tube assembly. The fin and tube assembly comprises fluid conduits to direct the fluid through the heat exchanger, to prevent mixing with the gas, and to provide a heat transfer surface or pathway between the fluid and the gas. A heat transfer element is provided in the fin and tube assembly to provide extended heat transfer surfaces for the fluid conduits. The heat transfer element is corrugated to form fins between alternating ridges and grooves that define flow channels for directing the gas flow. The fins are fabricated from a thin, heat conductive material containing numerous orifices or pores for transpiring the gas out of the flow channel. The grooves are closed or only partially open so that all or substantially all of the gas is transpired through the fins so that heat is exchanged on the front and back surfaces of the fins and also within the interior of the orifices, thereby significantly increasing the available the heat transfer surface of the heat exchanger. The transpired fins also increase heat transfer effectiveness of the heat exchanger by increasing the heat transfer coefficient by disrupting boundary layer development on the fins and by establishing other beneficial gas flow patterns, all at desirable pressure drops.

  14. High-Temperature High-Efficiency Solar Thermoelectric Generators

    SciTech Connect (OSTI)

    Baranowski, LL; Warren, EL; Toberer, ES

    2014-03-01

    Inspired by recent high-efficiency thermoelectric modules, we consider thermoelectrics for terrestrial applications in concentrated solar thermoelectric generators (STEGs). The STEG is modeled as two subsystems: a TEG, and a solar absorber that efficiently captures the concentrated sunlight and limits radiative losses from the system. The TEG subsystem is modeled using thermoelectric compatibility theory; this model does not constrain the material properties to be constant with temperature. Considering a three-stage TEG based on current record modules, this model suggests that 18% efficiency could be experimentally expected with a temperature gradient of 1000A degrees C to 100A degrees C. Achieving 15% overall STEG efficiency thus requires an absorber efficiency above 85%, and we consider two methods to achieve this: solar-selective absorbers and thermally insulating cavities. When the TEG and absorber subsystem models are combined, we expect that the STEG modeled here could achieve 15% efficiency with optical concentration between 250 and 300 suns.

  15. North American Overview - Heat Pumps Role in Buildings Energy Efficiency Improvement

    SciTech Connect (OSTI)

    Baxter, Van D [ORNL; Bouza, Antonio [U.S. Department of Energy; Gigure, Daniel [Natural Resources Canada; Hosatte, Sophie [Natural Resources Canada

    2011-01-01

    A brief overview of the situation in North America regarding buildings energy use and the current and projected heat pump market is presented. R&D and deployment strategies for heat pumps, and the impacts of the housing market and efficiency regulations on the heating and cooling equipment market are summarized as well.

  16. Using Exergy Analysis Methodology to Assess the Heating Efficiency of an Electric Heat Pump

    E-Print Network [OSTI]

    Ao, Y.; Duanmu, L.; Shen, S.

    2006-01-01

    , and 3) we would better improve the room structure and floor shape in order to heat the room well in a low temperature heating system....

  17. Integrated Solar Thermochemical Reaction System for High Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Integrated Solar Thermochemical Reaction System for High Efficiency Production of Electricity Integrated Solar Thermochemical Reaction System for High Efficiency Production of...

  18. Advanced Combustion Technology to Enable High Efficiency Clean...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technology to Enable High Efficiency Clean Combustion Advanced Combustion Technology to Enable High Efficiency Clean Combustion Summary of advanced combustion research at Cummins...

  19. Tailored Materials for High Efficiency CIDI Engines (Caterpillar...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency CIDI Engines (Caterpillar CRADA) Tailored Materials for High Efficiency CIDI Engines (Caterpillar CRADA) 2009 DOE Hydrogen Program and Vehicle Technologies Program...

  20. Unregulated Emissions from High-Efficiency Clean Combustion Modes...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Unregulated Emissions from High-Efficiency Clean Combustion Modes - ORNL-FEERC Poster presentation at...

  1. Novel Materials for High Efficiency Direct Methanol Fuel Cells...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Materials for High Efficiency Direct Methanol Fuel Cells Novel Materials for High Efficiency Direct Methanol Fuel Cells Presented at the Department of Energy Fuel Cell Projects...

  2. Highly Energy Efficient Directed Green Liquor Utilization (D...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Highly Energy Efficient Directed Green Liquor Utilization (D-GLU) Pulping Highly Energy Efficient Directed Green Liquor Utilization (D-GLU) Pulping This factsheet describes a...

  3. High Thermal Efficiency and Low Emissions with Supercritical...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Thermal Efficiency and Low Emissions with Supercritical Gasoline Injection-Ignition in a Light Duty Engine High Thermal Efficiency and Low Emissions with Supercritical...

  4. Energy Efficiency Opportunities in Federal High Performance Computing...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

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

  5. Enabling the Next Generation of High Efficiency Engines | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the Next Generation of High Efficiency Engines Enabling the Next Generation of High Efficiency Engines Discusses challenges and opportunities for next generation internal...

  6. Electrical and Thermal Transport Optimization of High Efficient...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Electrical and Thermal Transport Optimization of High Efficient n-type Skutterudites Electrical and Thermal Transport Optimization of High Efficient n-type Skutterudites Work on...

  7. Syngas Enhanced High Efficiency Low Temperature Combustion for...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Enhanced High Efficiency Low Temperature Combustion for Clean Diesel Engines Syngas Enhanced High Efficiency Low Temperature Combustion for Clean Diesel Engines A significant...

  8. Low Temperature Combustion Demonstrator for High Efficiency Clean...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Demonstrator for High Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Applied low temperature combustion to the Navistar...

  9. Low-Temperature Combustion Demonstrator for High-Efficiency Clean...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion Low-Temperature Combustion Demonstrator for High-Efficiency Clean Combustion 2010 DOE Vehicle...

  10. Evaluation of High Efficiency Clean Combustion (HECC) Strategies...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High Efficiency Clean Combustion (HECC) Strategies for Meeting Future Emissions Regulations in Light-Duty Engines Evaluation of High Efficiency Clean Combustion (HECC) Strategies...

  11. Combustion Targets for Low Emissions and High Efficiency | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Targets for Low Emissions and High Efficiency Combustion Targets for Low Emissions and High Efficiency 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and...

  12. Low Temperature Combustion Demonstrator for High Efficiency Clean...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion 2009 DOE Hydrogen Program...

  13. Greensburg Implements High-Efficiency Building Codes to Achieve...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Greensburg Implements High-Efficiency Building Codes to Achieve Long-Term Energy Savings Greensburg Implements High-Efficiency Building Codes to Achieve Long-Term Energy Savings...

  14. Progress toward Development of a High-Efficiency Zonal Thermoelectric...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    toward Development of a High-Efficiency Zonal Thermoelectric HVAC System for Automotive Applications Progress toward Development of a High-Efficiency Zonal Thermoelectric HVAC...

  15. Development of a High-Efficiency Zonal Thermoelectric HVAC System...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    a High-Efficiency Zonal Thermoelectric HVAC System for Automotive Applications Development of a High-Efficiency Zonal Thermoelectric HVAC System for Automotive Applications...

  16. Analyses Guided Optimization of Wide Range and High Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Analyses Guided Optimization of Wide Range and High Efficiency Turbocharger Compressor Analyses Guided Optimization of Wide Range and High Efficiency Turbocharger Compressor...

  17. Heavy-Duty Engine Combustion Optimization for High Thermal Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion Optimization for High Thermal Efficiency Targeting EPA 2010 Emissions Heavy-Duty Engine Combustion Optimization for High Thermal Efficiency Targeting EPA 2010 Emissions...

  18. Glass-like thermal conductivity in high efficiency thermoelectric...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Glass-like thermal conductivity in high efficiency thermoelectric materials Glass-like thermal conductivity in high efficiency thermoelectric materials Discusses strategies to...

  19. Modelling and fabrication of high-efficiency silicon solar cells

    SciTech Connect (OSTI)

    Rohatgi, A.; Smith, A.W.; Salami, J.

    1991-10-01

    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.

  20. Magnetic Refrigeration Technology for High Efficiency Air Conditioning

    SciTech Connect (OSTI)

    Boeder, A; Zimm, C

    2006-09-30

    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.

  1. Control of Electron Beam Using Strong Magnetic Field for Efficient Core Heating in Fast Ignition

    E-Print Network [OSTI]

    Johzaki, T; Sentoku, Y; Sunahara, A; Nagatomo, H; Sakagami, H; Mima, K; Fujioka, S; Shiraga, H

    2014-01-01

    For enhancing the core heating efficiency in electron-driven fast ignition, we proposed the fast electron beam guiding using externally applied longitudinal magnetic fields. Based on the PIC simulations for the FIREX-class experiments, we demonstrated the sufficient beam guiding performance in the collisional dense plasma by kT-class external magnetic fields for the case with moderate mirror ratio (~<10 ). Boring of the mirror field was found through the formation of magnetic pipe structure due to the resistive effects, which indicates a possibility of beam guiding in high mirror field for higher laser intensity and/or longer pulse duration.

  2. Limits in high efficiency quantum frequency conversion

    E-Print Network [OSTI]

    Nicols Quesada; J. E. Sipe

    2015-08-13

    Frequency conversion is an enabling process in many quantum information protocols. In this letter we study fundamental limits to high efficiency frequency conversion imposed by time ordering corrections. Using the Magnus expansion, we argue that these corrections, which are usually considered detrimental, can be used to increase the efficiency of conversion under certain circumstances. The corrections induce a nonlinear behaviour in the probability of upconversion as a function of the pump intensity, significantly modifying the sinusoidal Rabi oscillations that are otherwise expected. Finally, by using a simple scaling argument, we explain why cascaded frequency conversion devices attenuate time ordering corrections, allowing the construction of near ideal quantum pulse gates.

  3. High Efficiency Solar Integrated Roof Membrane Product

    SciTech Connect (OSTI)

    Partyka, Eric; Shenoy, Anil

    2013-05-15

    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.

  4. Polymer Separators for High Power, High Efficiency Microbial Fuel Cells

    E-Print Network [OSTI]

    1 Polymer Separators for High Power, High Efficiency Microbial Fuel Cells Guang Chen, Bin) was dissolved in 23 g H2O at 90 C to prepare ~8 wt% transparent viscous polymer solution. To this solution in the water-swollen membranes. MFC reactor construction Anodes were composed of ammonia-treated carbon brushes

  5. Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form

    E-Print Network [OSTI]

    Birmingham, University of

    Efficient Heat Engines and Heat Pumps (10 credits) The aim of the module is to introduce the various ideal thermodynamic cycles that form the basis for power generation, heat pumping and IC Engines performance. Syllabus Heat Engines and Heat Pumps Second Law of Thermodynamics, Concept

  6. HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

    SciTech Connect (OSTI)

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

    2003-06-01

    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

  7. Optimization of a high efficiency FEL amplifier

    E-Print Network [OSTI]

    Schneidmiller, E A

    2014-01-01

    The problem of an efficiency increase of an FEL amplifier is now of great practical importance. Technique of undulator tapering in the post-saturation regime is used at the existing x-ray FELs LCLS and SACLA, and is planned for use at the European XFEL, Swiss FEL, and PAL XFEL. There are also discussions on the future of high peak and average power FELs for scientific and industrial applications. In this paper we perform detailed analysis of the tapering strategies for high power seeded FEL amplifiers. Application of similarity techniques allows us to derive universal law of the undulator tapering.

  8. High Efficiency Colloidal Quantum Dot Phosphors

    SciTech Connect (OSTI)

    Kahen, Keith

    2013-12-31

    The project showed that non-Cd containing, InP-based nanocrystals (semiconductor materials with dimensions of ~6 nm) have high potential for enabling next-generation, nanocrystal-based, on chip phosphors for solid state lighting. Typical nanocrystals fall short of the requirements for on chip phosphors due to their loss of quantum efficiency under the operating conditions of LEDs, such as, high temperature (up to 150 C) and high optical flux (up to 200 W/cm2). The InP-based nanocrystals invented during this project maintain high quantum efficiency (>80%) in polymer-based films under these operating conditions for emission wavelengths ranging from ~530 to 620 nm. These nanocrystals also show other desirable attributes, such as, lack of blinking (a common problem with nanocrystals which limits their performance) and no increase in the emission spectral width from room to 150 C (emitters with narrower spectral widths enable higher efficiency LEDs). Prior to these nanocrystals, no nanocrystal system (regardless of nanocrystal type) showed this collection of properties; in fact, other nanocrystal systems are typically limited to showing only one desirable trait (such as high temperature stability) but being deficient in other properties (such as high flux stability). The project showed that one can reproducibly obtain these properties by generating a novel compositional structure inside of the nanomaterials; in addition, the project formulated an initial theoretical framework linking the compositional structure to the list of high performance optical properties. Over the course of the project, the synthetic methodology for producing the novel composition was evolved to enable the synthesis of these nanomaterials at a cost approximately equal to that required for forming typical conventional nanocrystals. Given the above results, the last major remaining step prior to scale up of the nanomaterials is to limit the oxidation of these materials during the tens of thousands of hours of LED operation. Once the LED phosphor lifetime specifications are met, these nanocrystals will enable white LEDs for solid state lighting to simultaneously have increased efficiency and improved light quality, in addition to enabling the creation of custom light spectrums. These improvements to white LEDs will help accelerate the adoption of SSL, leading to large savings in US and worldwide energy costs.

  9. Low GWP Working Fluid for High Temperature Heat Pumps

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Low GWP Working Fluid for High Temperature Heat Pumps: DR-2 Chemical Stability at High Temperatures Temp Heat Pumps: DR-2 Very Low GWP AND Non-Flammable HFC-245fa DR-2 Chemical Formula CF3CH2CHF2 HFO 171.3 Pcr [MPa] 3.65 2.9 Kontomaris-DuPont; European Heat Pump Summit, Nuremberg, October 15th, 2013

  10. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    SciTech Connect (OSTI)

    Hong, Tainzhen; Liu, Xaiobing

    2009-11-01

    With the current movement toward net zero energy buildings, many technologies are promoted with emphasis on their superior energy efficiency. The variable refrigerant flow (VRF) and ground source heat pump (GSHP) systems are probably the most competitive technologies among these. However, there are few studies reporting the energy efficiency of VRF systems compared with GSHP systems. In this article, a preliminary comparison of energy efficiency between the air-source VRF and GSHP systems is presented. The computer simulation results show that GSHP system is more energy efficient than the air-source VRF system for conditioning a small office building in two selected US climates. In general, GSHP system is more energy efficient than the air-source VRV system, especially when the building has significant heating loads. For buildings with less heating loads, the GSHP system could still perform better than the air-source VRF system in terms of energy efficiency, but the resulting energy savings may be marginal.

  11. ENERGY EFFICIENCY TECHNOLOGY ROADMAP VOLUME 8: COMBINED HEAT...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of the Energy Efficiency Technology Roadmap (EE Roadmap), published by the Bonneville Power Administration (BPA) on behalf of regional stakeholders. For the background and...

  12. ENERGY EFFICIENCY TECHNOLOGY ROADMAP VOLUME 5: HEATING, VENTILATION...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    and space conditioning systems in a cost effective efficient package Need information on energy performance and optimization Need for cost effective demand response capability...

  13. Energy Efficient Clothes Dryer with IR Heating and Electrostatic...

    Broader source: Energy.gov (indexed) [DOE]

    GE Global Research More Documents & Publications Schematic of drum-integrated thermoelectric dryer. Novel Energy-Efficient Thermoelectric Clothes Dryer Novel Ultra-Low-Energy...

  14. Charge Trapping in High Efficiency Alternating Copolymers: Implication...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Charge Trapping in High Efficiency Alternating Copolymers: Implications in Organic Photovoltaic Device Efficiency Home > Research > ANSER Research Highlights > Charge Trapping in...

  15. High Engine Efficiency at 2010 Emissions | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Engine Efficiency at 2010 Emissions High Engine Efficiency at 2010 Emissions 2005 Diesel Engine Emissions Reduction (DEER) Conference Presentations and Posters 2005deernelson.pdf...

  16. High-Efficiency Window Air Conditioners - Building America Top...

    Energy Savers [EERE]

    Efficiency Window Air Conditioners - Building America Top Innovation High-Efficiency Window Air Conditioners - Building America Top Innovation This photo shows a window air...

  17. Advanced High Efficiency Clean Diesel Combustion with Low Cost...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency Clean Diesel Combustion with Low Cost for Hybrid Engines Advanced High Efficiency Clean Diesel Combustion with Low Cost for Hybrid Engines Clean, in-cylinder combustion...

  18. High Efficiency Full Expansion (FEx) Engine for Automotive Application...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Full Expansion (FEx) Engine for Automotive Applications High Efficiency Full Expansion (FEx) Engine for Automotive Applications Large increases in engine thermal efficiency result...

  19. Ultra Efficient Combined Heat, Hydrogen, and Power System- Presentation by FuelCell Energy, June 2011

    Broader source: Energy.gov [DOE]

    Presentation on Ultra Efficient Combined Heat, Hydrogen, and Power System, given by Pinakin Patel at the U.S. DOE Industrial Distributed Energy Portfolio Review Meeting in Washington, D.C. on June 1-2, 2011.

  20. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    for thermal comfort. Energy and Buildings 2002;34:593-9.IEA. Technology Roadmap. Energy-efficient Buildings: HeatingH, Arens E, Webster T. Energy Savings from Extended Air

  1. Analysis of space heating and domestic hot water systems for energy-efficient residential buildings

    SciTech Connect (OSTI)

    Dennehy, G

    1983-04-01

    An analysis of the best ways of meeting the space heating and domestic hot water (DHW) needs of new energy-efficient houses with very low requirements for space heat is provided. The DHW load is about equal to the space heating load in such houses in northern climates. The equipment options which should be considered are discussed, including new equipment recently introduced in the market. It is concluded that the first consideration in selecting systems for energy-efficient houses should be identification of the air moving needs of the house for heat distribution, heat storage, ventilation, and ventilative cooling. This is followed, in order, by selection of the most appropriate distribution system, the heating appliances and controls, and the preferred energy source, gas, oil, or electricity.

  2. High Quantum Efficiency OLED Lighting Systems

    SciTech Connect (OSTI)

    Shiang, Joseph [General Electric (GE) Global Research, Fairfield, CT (United States)

    2011-09-30

    The overall goal of the program was to apply improvements in light outcoupling technology to a practical large area plastic luminaire, and thus enable the product vision of an extremely thin form factor high efficiency large area light source. The target substrate was plastic and the baseline device was operating at 35 LPW at the start of the program. The target LPW of the program was a >2x improvement in the LPW efficacy and the overall amount of light to be delivered was relatively high 900 lumens. Despite the extremely difficult challenges associated with scaling up a wet solution process on plastic substrates, the program was able to make substantial progress. A small molecule wet solution process was successfully implemented on plastic substrates with almost no loss in efficiency in transitioning from the laboratory scale glass to large area plastic substrates. By transitioning to a small molecule based process, the LPW entitlement increased from 35 LPW to 60 LPW. A further 10% improvement in outcoupling efficiency was demonstrated via the use of a highly reflecting cathode, which reduced absorptive loss in the OLED device. The calculated potential improvement in some cases is even larger, ~30%, and thus there is considerable room for optimism in improving the net light coupling efficacy, provided absorptive loss mechanisms are eliminated. Further improvements are possible if scattering schemes such as the silver nanowire based hard coat structure are fully developed. The wet coating processes were successfully scaled to large area plastic substrate and resulted in the construction of a 900 lumens luminaire device.

  3. Design and global optimization of high-efficiency thermophotovoltaic systems

    E-Print Network [OSTI]

    Bermel, Peter A.

    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 ...

  4. ASHRAE Minimum Efficiency Requirements Tables for Heating and Cooling Product Categories

    Broader source: Energy.gov [DOE]

    The Federal Energy Management Program (FEMP) created tables that mirror American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) 90.1-2013 tables, which include minimum efficiency requirements for FEMP-designated and ENERGY STAR-qualified heating and cooling product categories. Download the tables below to incorporate FEMP and ENERGY STAR purchasing requirements into federal product acquisition documents.

  5. High-Efficiency Multijunction Photovoltaics | Center for Energy Efficient

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory ofDid you notHeat Pumps Heat Pumps An error occurred. Try| CenterMaterials

  6. High Efficiency, Illumination Quality OLEDs for Lighting

    SciTech Connect (OSTI)

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

    2008-03-31

    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

  7. High Efficient Clean Combustion for SuperTruck | Department of...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficient Clean Combustion for SuperTruck High Efficient Clean Combustion for SuperTruck Presentation given at the 16th Directions in Engine-Efficiency and Emissions Research...

  8. Multiwalled carbon nanotube/polydimethylsiloxane composite films as high performance flexible electric heating elements

    SciTech Connect (OSTI)

    Yan, Jing; Jeong, Young Gyu, E-mail: ygjeong@cnu.ac.kr [Department of Advanced Organic Materials and Textile System Engineering, Chungnam National University, Daejeon 305-764 (Korea, Republic of)

    2014-08-04

    High performance elastomeric electric heating elements were prepared by incorporating various contents of pristine multiwalled carbon nanotube (MWCNT) in polydimethylsiloxane (PDMS) matrix by using an efficient solution-casting and curing technique. The pristine MWCNTs were identified to be uniformly dispersed in the PDMS matrix and the electrical percolation of MWCNTs was evaluated to be at ?0.27?wt.?%, where the electrical resistivity of the MWCNT/PDMS composite films dropped remarkably. Accordingly, the composite films with higher MWCNT contents above 0.3?wt.?% exhibit excellent electric heating performance in terms of temperature response rapidity and electric energy efficiency at constant applied voltages. In addition, the composite films, which were thermally stable up to 250?C, showed excellent heating-cooling cyclic performance, which was associated with operational stability in actual electric heating applications.

  9. DESIGN AND DEVELOPMENT TESTING OF AN IMPROVED (1 HIGH-EFFICIENCY WATER HEATER

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    #12;DESIGN AND DEVELOPMENT TESTING OF AN IMPROVED (1 HIGH-EFFICIENCY WATER HEATER (2} (3) (21 which uses a design approach quite different from the conventional center-flue water heater. While high heating. The design and performance of an early prototype is described in a previous paper (Ref. 2

  10. Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss

    SciTech Connect (OSTI)

    Kutscher, C.; Burkholder, F.; Stynes, J. K.

    2012-02-01

    The thermal efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The thermal efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain the thermal efficiency curve. This paper describes this approach and also makes the case that there are advantages to plotting collector efficiency versus the difference between the operating temperature and the ambient temperature at which the receiver heat loss was measured divided by radiation to a fractional power (on the order of 1/3 but obtained via data regression) - as opposed to the difference between operating and ambient temperatures divided by the radiation. The results are shown to be robust over wide ranges of ambient temperature, sky temperature, and wind speed.

  11. Development of a High Performance Air Source Heat Pump for the US Market

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; Shen, Bo [ORNL] [ORNL; Gao, Zhiming [ORNL] [ORNL; Baxter, Van D [ORNL] [ORNL; Iu, Ipseng [ORNL] [ORNL

    2011-01-01

    Heat pumps present a significant advantage over conventional residential heating technologies due to higher energy efficiencies and less dependence on imported oil. The US development of heat pumps dates back to the 1930 s with pilot units being commercially available in the 1950 s. Reliable and cost competitive units were available in the US market by the 1960 s. The 1973 oil embargo led to increased interest in heat pumps prompting significant research to improve performance, particularly for cold climate locations. Recent increasing concerns on building energy efficiency and environmental emissions have prompted a new wave of research in heat pump technology with special emphasis on reducing performance degradation at colder outdoor air temperatures. A summary of the advantages and limitations of several performance improvement options sought for the development of high performance air source heat pump systems for cold climate applications is the primary focus of this paper. Some recommendations for a high performance cold climate heat pump system design most suitable for the US market are presented.

  12. Advanced Thermoelectric Materials for Efficient Waste Heat Recovery in Process Industries

    SciTech Connect (OSTI)

    Adam Polcyn; Moe Khaleel

    2009-01-06

    The overall objective of the project was to integrate advanced thermoelectric materials into a power generation device that could convert waste heat from an industrial process to electricity with an efficiency approaching 20%. Advanced thermoelectric materials were developed with figure-of-merit ZT of 1.5 at 275 degrees C. These materials were not successfully integrated into a power generation device. However, waste heat recovery was demonstrated from an industrial process (the combustion exhaust gas stream of an oxyfuel-fired flat glass melting furnace) using a commercially available (5% efficiency) thermoelectric generator coupled to a heat pipe. It was concluded that significant improvements both in thermoelectric material figure-of-merit and in cost-effective methods for capturing heat would be required to make thermoelectric waste heat recovery viable for widespread industrial application.

  13. Development of a New Generation, High Efficiency PEM Fuel Cell...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    a New Generation, High Efficiency PEM Fuel Cell Based, CHP System Development of a New Generation, High Efficiency PEM Fuel Cell Based, CHP System Part of a 100 million fuel cell...

  14. Development of High-Efficiency Clean Combustion Engines Designs...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    High-Efficiency Clean Combustion Engines Designs for SI and CI Engines Development of High-Efficiency Clean Combustion Engines Designs for SI and CI Engines 2010 DOE Vehicle...

  15. High-Efficiency Receivers for Supercritical Carbon Dioxide Cycles...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications High-Efficiency Low-Cost Solar Receiver for Use in a Supercritical CO2 Recompression Cycle - FY13 Q1 High-Efficiency Receivers for...

  16. High Efficiency Organic Light Emitting Devices for Lighting

    SciTech Connect (OSTI)

    So, Franky; Tansu, Nelson; Gilchrist, James

    2013-06-30

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

  17. Simulation of High Efficiency Clean Combustion Engines and Detailed...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    ongoing work exploring fuel chemistry, analysis of and improving simulation methodologies for high efficiency clean combustion regimes, and computational performance...

  18. Analysis of highly-efficient electric residential HPWHs

    SciTech Connect (OSTI)

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

    2011-09-01

    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.

  19. Investigating potential light-duty efficiency improvements through simulation of turbo-compounding and waste-heat recovery systems

    SciTech Connect (OSTI)

    Edwards, Kevin Dean; Wagner, Robert M; Briggs, Thomas E

    2010-01-01

    Modern diesel engines used in light-duty transportation applications have peak brake thermal efficiencies in the range of 40-42% for high-load operation with substantially lower efficiencies at realistic road-load conditions. Thermodynamic energy and exergy analysis reveals that the largest losses from these engines are due to combustion irreversibility and heat loss to the coolant, through the exhaust, and by direct convection and radiation to the environment. Substantial improvement in overall engine efficiency requires reducing or recovering these losses. Unfortunately, much of the heat transfer either occurs at relatively low temperatures resulting in large entropy generation (such as in the air-charge cooler), is transferred to low-exergy flow streams (such as the oil and engine coolant), or is radiated or convected directly to the environment. While there are significant opportunities for recovery from the exhaust and EGR cooler for heavy-duty applications, achieving similar benefits for light-duty applications is complicated by transient, low-load operation at typical driving conditions and competition with the turbocharger and aftertreatment system for the limited thermal resources. We have developed an organic Rankine cycle model using GT-Suite to investigate the potential for efficiency improvement through waste-heat recovery from the exhaust and EGR cooler of a light-duty diesel engine. The model is used to examine the effects of efficiency-improvement strategies such as cylinder deactivation, use of advanced materials and improved insulation to limit ambient heat loss, and turbo-compounding on the steady-state performance of the ORC system and the availability of thermal energy for downstream aftertreatment systems. Results from transient drive-cycle simulations are also presented, and we discuss strategies to address operational difficulties associated with transient drive cycles and balancing the thermal requirements of waste-heat recovery, turbocharging or turbo-compounding, and exhaust aftertreatment.

  20. HIGH-EFFICIENCY POWER AMPLIFIERS FOR LINEAR TRANSMITTERS

    E-Print Network [OSTI]

    Popovic, Zoya

    HIGH-EFFICIENCY POWER AMPLIFIERS FOR LINEAR TRANSMITTERS by NESTOR DAVID LOPEZ B.S., University;This thesis entitled: High-Efficiency Power Amplifiers for Linear Transmitters written by Nestor David in the above mentioned discipline #12;Lopez, Nestor David (Ph.D., Electrical Engineering) High-Efficiency

  1. High efficiency, radiation-hard solar cells

    E-Print Network [OSTI]

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

    2004-01-01

    efficiency multijunction (MJ) solar cells use componentsin current multijunction (MJ) solar cells (GaAs and GaInP)

  2. Tailored Materials for High Efficiency CIDI Engines

    SciTech Connect (OSTI)

    Grant, G.J.; Jana, S.

    2012-03-30

    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.

  3. High SO2 Removal Efficiency Testing

    SciTech Connect (OSTI)

    Gary Blythe

    1997-02-12

    This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO Removal Testing," for 2 the time period 1 October through 31 December 1996. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems, to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO removal efficiency. The upgrades being 2 evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company?s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy?s Merom Station (Option I), Southwestern Electric Power Company?s Pirkey Station (Option II), PSI Energy?s Gibson Station (Option III), Duquesne Light?s Elrama Station (Option IV), and New York State Electric and Gas Corporation?s Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing has been planned at the Big Bend Station, and that testing commenced during the current quarter. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the first quarter of calendar year 1996. Section 5 contains a brief acknowledgment.

  4. High SO2 Removal Efficiency Testing

    SciTech Connect (OSTI)

    Gary Blythe

    1997-04-23

    This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO2 Removal Testing", for the time period 1 January through 31 March 1997. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems, to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO2 removal efficiency. The upgrades being evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company?s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy?s Merom Station (Option I), Southwestern Electric Power Company?s Pirkey Station (Option II), PSI Energy?s Gibson Station (Option III), Duquesne Light?s Elrama Station (Option IV), and New York State Electric and Gas Corporation?s (NYSEG) Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing is planned at the Big Bend Station. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the second quarter of calendar year 1997. Section 5 contains a brief acknowledgement.

  5. High SO2 Removal Efficiency Testing

    SciTech Connect (OSTI)

    Gary Blythe

    1997-07-29

    This document provides a discussion of the technical progress on DOE/PETC project number DE-AC22-92PC91338, "High Efficiency SO2 Removal Testing", for the time period 1 April through 30 June 1997. The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO2 removal efficiency. The upgrades being evaluated mostly involve using performance additives in the FGD systems. The "base" project involved testing at the Tampa Electric Company?s Big Bend Station. All five potential options to the base program have been exercised by DOE, involving testing at Hoosier Energy?s Merom Station (Option I), Southwestern Electric Power Company?s Pirkey Station (Option II), PSI Energy?s Gibson Station (Option III), Duquesne Light?s Elrama Station (Option IV), and New York State Electric and Gas Corporation?s Kintigh Station (Option V). The originally planned testing has been completed for all six sites. However, additional testing is being conducted at the Big Bend Station. The remainder of this document is divided into four sections. Section 2, Project Summary, provides a brief overview of the status of technical efforts on this project. Section 3, Results, summarizes the outcome from technical efforts during the quarter, or results from prior quarters that have not been previously reported. In Section 4, Plans for the Next Reporting Period, an overview is provided of the technical efforts that are anticipated for the third quarter of calendar year 1997. Section 5 contains a brief acknowledgment.

  6. High temperature performance of high-efficiency, multi-layer solar selective coatings for tower applications

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Gray, M. H.; Tirawat, R.; Kessinger, K. A.; Ndione, P. F.

    2015-05-01

    The roadmap to next-generation concentrating solar power plants anticipates a progression to central towers with operating temperatures in excess of 650C. These higher temperatures are required to drive higher power-cycle efficiencies, resulting in lower cost energy. However, these conditions also place a greater burden on the materials making up the receiver. Any novel absorber material developed for next-generation receivers must be stable in air, cost effective, and survive thousands of heating and cooling cycles. The collection efficiency of a power tower plant can be increased if the energy absorbed by the receiver is maximized while the heat loss from themorereceiver to the environment is minimized. Thermal radiation losses can be significant (>7% annual energy loss) with receivers at temperatures above 650C. We present progress toward highly efficient and durable solar selective absorbers (SSAs) intended for operating temperatures from 650C to 1000C. Selective efficiency (?sel) is defined as the energy retained by the absorber, accounting for both absorptance and emittance, relative to the energy incident on the surface. The low emittance layers of multilayer SSAs are binary compounds of refractory metals whose material properties indicate that coatings formed of these materials should be oxidation resistant in air to 800-1200C. On this basis, we initially developed a solar selective coating for parabolic troughs. This development has been successfully extended to meet the absorptance and emittance objectives for the more demanding, high temperature regime. We show advancement in coating materials, processing and designs resulting in the initial attainment of target efficiencies ?sel > 0.91 for proposed tower conditions. Additionally, spectral measurements show that these coatings continue to perform at targeted levels after cycling to temperatures of 1000C in environments of nitrogen and forming gas.less

  7. High temperature performance of high-efficiency, multi-layer solar selective coatings for tower applications

    SciTech Connect (OSTI)

    Gray, M. H.; Tirawat, R.; Kessinger, K. A.; Ndione, P. F.

    2015-05-01

    The roadmap to next-generation concentrating solar power plants anticipates a progression to central towers with operating temperatures in excess of 650C. These higher temperatures are required to drive higher power-cycle efficiencies, resulting in lower cost energy. However, these conditions also place a greater burden on the materials making up the receiver. Any novel absorber material developed for next-generation receivers must be stable in air, cost effective, and survive thousands of heating and cooling cycles. The collection efficiency of a power tower plant can be increased if the energy absorbed by the receiver is maximized while the heat loss from the receiver to the environment is minimized. Thermal radiation losses can be significant (>7% annual energy loss) with receivers at temperatures above 650C. We present progress toward highly efficient and durable solar selective absorbers (SSAs) intended for operating temperatures from 650C to 1000C. Selective efficiency (?sel) is defined as the energy retained by the absorber, accounting for both absorptance and emittance, relative to the energy incident on the surface. The low emittance layers of multilayer SSAs are binary compounds of refractory metals whose material properties indicate that coatings formed of these materials should be oxidation resistant in air to 800-1200C. On this basis, we initially developed a solar selective coating for parabolic troughs. This development has been successfully extended to meet the absorptance and emittance objectives for the more demanding, high temperature regime. We show advancement in coating materials, processing and designs resulting in the initial attainment of target efficiencies ?sel > 0.91 for proposed tower conditions. Additionally, spectral measurements show that these coatings continue to perform at targeted levels after cycling to temperatures of 1000C in environments of nitrogen and forming gas.

  8. Ultra Efficient Combined Heat, Hydrogen, and Power System

    Broader source: Energy.gov [DOE]

    In order for metal products to have desired properties, most metal is thermally processed at a high temperature one or more times under a controlled atmosphere. There are many different thermal...

  9. High efficiency, radiation-hard solar cells

    SciTech Connect (OSTI)

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

    2004-10-22

    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.

  10. High-Efficiency Solar Cogeneration with Thermophotovoltaic &...

    Broader source: Energy.gov (indexed) [DOE]

    targeted 'Solar Cogeneration' technologies to maximize energy generation & energy efficiency from the building's solar insolation resources. Project presents a novel, low-cost...

  11. High Efficiency Low Emission Refrigeration System

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency Low Emission Refrigeration System 2014 Building Technologies Office Peer Review Brian Fricke, frickeba@ornl.gov Oak Ridge National Laboratory Project Summary Timeline:...

  12. High-Efficiency Deflection of High-Energy Protons through Axial...

    Office of Scientific and Technical Information (OSTI)

    High-Efficiency Deflection of High-Energy Protons through Axial Channeling in a Bent Crystal Citation Details In-Document Search Title: High-Efficiency Deflection of High-Energy...

  13. High Efficiency Single Photon Detection via Frequency Up-Conversion

    E-Print Network [OSTI]

    Kwiat, Paul

    High Efficiency Single Photon Detection via Frequency Up-Conversion Aaron P. VanDevender and Paul G the much higher efficiency of silicon APDs at these wavelengths. We have used a Periodically Poled Lithium. We observed conversion efficiencies as high as 80%, and demonstrated scaling down to the single

  14. Control apparatus and method for efficiently heating a fuel processor in a fuel cell system

    DOE Patents [OSTI]

    Doan, Tien M.; Clingerman, Bruce J.

    2003-08-05

    A control apparatus and method for efficiently controlling the amount of heat generated by a fuel cell processor in a fuel cell system by determining a temperature error between actual and desired fuel processor temperatures. The temperature error is converted to a combustor fuel injector command signal or a heat dump valve position command signal depending upon the type of temperature error. Logic controls are responsive to the combustor fuel injector command signals and the heat dump valve position command signal to prevent the combustor fuel injector command signal from being generated if the heat dump valve is opened or, alternately, from preventing the heat dump valve position command signal from being generated if the combustor fuel injector is opened.

  15. Case Studies of High Efficiency Electric Motor Applicability

    E-Print Network [OSTI]

    Wagner, J. R.

    1985-01-01

    Much has been written about the advantages and disadvantages of high efficiency electric motors. For a given motor application it is possible to find literature that enables a plant engineer to make an informed choice between a standard efficiency...

  16. Energy efficiency indicators for high electric-load buildings

    SciTech Connect (OSTI)

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

    2003-06-01

    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.

  17. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    E-Print Network [OSTI]

    Singer, Brett C.

    2010-01-01

    Achieving sustainability goals may require High Performanceperformance). Coordination and potentially consolidation of energy and sustainabilityPerformance Healthcare Buildings: A Roadmap to Improved Energy Efficiency 11-Sept-2009 o Link government reimbursements to efficiency and sustainability

  18. Techniques for high-efficiency outphasing power amplifiers

    E-Print Network [OSTI]

    Godoy, Philip (Philip Andrew)

    2011-01-01

    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 ...

  19. Development of the High Efficiency X1 Rotary Diesel Engine

    Broader source: Energy.gov [DOE]

    This poster describes the design, modeling, and build of a 70-hp prototype of a high efficiency hybrid cycle engine that is expected to attain 57 percent efficiency across a range of loads.

  20. High efficiency pulse motor drive for robotic propulsion

    E-Print Network [OSTI]

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

    2013-01-01

    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 ...

  1. Generation of a Parabolic Trough Collector Efficiency Curve from Separate Measurements of Outdoor Optical Efficiency and Indoor Receiver Heat Loss: Preprint

    SciTech Connect (OSTI)

    Kutscher, C.; Burkholder, F.; Stynes, K.

    2010-10-01

    The overall efficiency of a parabolic trough collector is a function of both the fraction of direct normal radiation absorbed by the receiver (the optical efficiency) and the heat lost to the environment when the receiver is at operating temperature. The overall efficiency can be determined by testing the collector under actual operating conditions or by separately measuring these two components. This paper describes how outdoor measurement of the optical efficiency is combined with laboratory measurements of receiver heat loss to obtain an overall efficiency curve. Further, it presents a new way to plot efficiency that is more robust over a range of receiver operating temperatures.

  2. High speed linear induction motor efficiency optimization

    E-Print Network [OSTI]

    Johnson, Andrew P. (Andrew Peter)

    2005-01-01

    One of the reasons linear motors, a technology nearly a century old, have not been adopted for a large number of linear motion applications is that they have historically had poor efficiencies. This has restricted the ...

  3. Highly efficient 6-stroke engine cycle with water injection

    DOE Patents [OSTI]

    Szybist, James P; Conklin, James C

    2012-10-23

    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.

  4. Energy Savings Potential and Opportunities for High-Efficiency...

    Broader source: Energy.gov (indexed) [DOE]

    sponsored this assignment and provided comments on draft versions of the report. iii Energy Savings Potential and Opportunities for High-Efficiency Electric Motors in Residential...

  5. Technology and System Level Demonstration of Highly Efficient...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    and Peer Evaluation arravt081vssnewhouse2011o.pdf More Documents & Publications Technology and System Level Demonstration of Highly Efficient and Clean, Diesel Powered Class 8...

  6. Technology and System Level Demonstration of Highly Efficient...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Evaluation Meeting arravt081vssnewhouse2012o.pdf More Documents & Publications Technology and System Level Demonstration of Highly Efficient and Clean, Diesel Powered Class 8...

  7. High Efficiency Clean Combustion for Heavy-Duty Engine

    Broader source: Energy.gov [DOE]

    Explore advancements in engine combustion systems using high-efficiency clean combustion (HECC) techniques to minimize engine-out emissions while optimizing fuel economy.

  8. Materials-Enabled High-Efficiency Diesel Engines (CRADA with...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Engines (CRADA with Caterpillar) Materials-Enabled High-Efficiency Diesel Engines (CRADA with Caterpillar) 2009 DOE Hydrogen Program and Vehicle Technologies Program Annual Merit...

  9. Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems Surface Coatings Enhance Wear Resistance of Metals, Saving Energy and Increasing Component Life...

  10. Vehicle Technologies Office Merit Review 2014: High Efficiency...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    about high efficiency clean combustion in multi-cylinder light-duty engines. ace016curran2014o.pdf More Documents & Publications Vehicle Technologies Office Merit Review...

  11. Field Demonstration of High Efficiency Ultra-Low-Temperature...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Ultra-Low-Temperature Laboratory Freezers Field Demonstration of High Efficiency Ultra-Low-Temperature Laboratory Freezers Ultra-low temperature laboratory freezers (ULTs) are some...

  12. Project Profile: High-Efficiency Receivers for Supercritical...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    that is greater than or equal to 750C Maintaining high receiver efficiency Retaining durability over the lifetime of the CSP plant Significantly reducing the cost as compared...

  13. Energy Efficiency Opportunities in Federal High Performance Computing...

    Broader source: Energy.gov (indexed) [DOE]

    Case study describes an outline of energy efficiency opportunities in federal high-performance computing data centers. dchpcc.pdf More Documents & Publications Case Study:...

  14. Enabling High Efficiency Low Temperature Combustion by Adaptive...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low Temperature Combustion by Adaptive In-Situ Jet Cooling Enabling High Efficiency Low Temperature Combustion by Adaptive In-Situ Jet Cooling A new approach, called...

  15. High Efficiency Clean Combustion Engine Designs for Gasoline...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Engine Designs for Gasoline and Diesel Engines High Efficiency Clean Combustion Engine Designs for Gasoline and Diesel Engines 2009 DOE Hydrogen Program and Vehicle Technologies...

  16. Selective ammonia slip catalyst enabling highly efficient NOx...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    enabling highly efficient NOx removal requirements of the future A low precious metal loading ammonia-slip catalyst was developed that is able to oxidize the ammonia that...

  17. Advanced CFD Models for High Efficiency Compression Ignition Engines

    Broader source: Energy.gov [DOE]

    Advanced CFD models for high efficiency compression-ignition engines can be used to show how turbulence-chemistry interactions influence autoignition and combustion.

  18. Advanced CFD Models for High Efficiency Compression Ignition...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for high efficiency compression-ignition engines can be used to show how turbulence-chemistry interactions influence autoignition and combustion. p-19raja.pdf More Documents &...

  19. Optimization Online - Efficient high-precision dense matrix algebra ...

    E-Print Network [OSTI]

    John Gunnels

    2008-11-10

    Nov 10, 2008 ... Efficient high-precision dense matrix algebra on parallel architectures for nonlinear discrete optimization. John Gunnels(gunnels ***at***...

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

    SciTech Connect (OSTI)

    2011-01-31

    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.

  1. Playing Hot and Cold: How Can Russian Heat Policy Find Its Way Toward Energy Efficiency?

    SciTech Connect (OSTI)

    Roshchanka, Volha; Evans, Meredydd

    2012-09-15

    The Russian district heating has a large energy-saving potential, and, therefore, need for investments. The scale of needed investments is significant: the government estimates that 70 percent of the district heating infrastructure needs replacement or maintenance, a reflection of decades of under investment. Government budgets will be unable to cover them, and iInvolvingement ofthe private industry will be critical to attracting the necessary investementis necessary. For private parties to invest in district heating facilities across Russia, and not only in pockets of already successful enterprises, regulators have to develop a comprehensive policy that works district heating systems under various conditionscost-reflective tariffs, metering, incentives for efficiency and social support for the neediest (instead of subsidies for all).

  2. Hydraulic transmissivity and heat exchange efficiency of open fractures: a model based on lowpass filtered apertures

    E-Print Network [OSTI]

    Neuville, Amlie; Schmittbuhl, Jean; 10.1111/j.1365-246X.2011.05126.x

    2011-01-01

    Natural open joints in rocks commonly present multi-scale self-affine apertures. This geometrical complexity affects fluid transport and heat exchange between the flow- ing fluid and the surrounding rock. In particular, long range correlations of self-affine apertures induce strong channeling of the flow which influences both mass and heat advection. A key question is to find a geometrical model of the complex aperture that describes at best the macroscopic properties (hydraulic conductivity, heat exchange) with the smallest number of parameters. Solving numerically the Stokes and heat equa- tions with a lubrication approximation, we show that a low pass filtering of the aperture geometry provides efficient estimates of the effective hydraulic and thermal properties (apertures). A detailed study of the influence of the bandwidth of the lowpass filtering on these transport properties is also performed. For instance, keeping the information of amplitude only of the largest Fourier length scales allows us to rea...

  3. High-power ELF radiation generated by modulated HF heating of the ionosphere can cause Earthquakes, Cyclones and localized heating

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    transmitter radiates a strong beam of high- frequency (HF) waves modulated at ELF. This HF heating modulates-frequency (HF) radiation in the megahertz range [7]. This heating modulates the electron's temperature in the D

  4. High efficiency, oxidation resistant radio frequency susceptor

    DOE Patents [OSTI]

    Besmann, Theodore M.; Klett, James W.

    2004-10-26

    An article and method of producing an article for converting energy from one form to another having a pitch-derived graphitic foam carbon foam substrate and a single layer coating applied to all exposed surfaces wherein the coating is either silicon carbide or carbides formed from a Group IVA metal. The article is used as fully coated carbon foam susceptors that more effectively absorb radio frequency (RF) band energy and more effectively convert the RF energy into thermal band energy or sensible heat. The essentially non-permeable coatings also serve as corrosion or oxidation resistant barriers.

  5. Nanocoatings for High-Efficiency Industrial Hydraulic and Tooling Systems

    SciTech Connect (OSTI)

    Clifton B. Higdon III

    2011-01-07

    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.

  6. A Natural Gas, High Compression Ratio, High Efficiency ICRE

    Broader source: Energy.gov [DOE]

    Using natural gas and gasoline modeling, indications are that a free piston-floating stroke engine configuration can realize engine efficiency greater than 60 percent.

  7. Multiscale approaches to high efficiency photovoltaics

    E-Print Network [OSTI]

    Connolly, J P; Mencaraglia, D; Rimada, Julio C; Nejim, Ahmed; Sanchez, G

    2015-01-01

    While renewable energies are achieving parity around the globe, efforts to reach higher solar cell efficiencies becomes ever more difficult as they approach the limiting efficiency. The so-called third generation concepts attempt to break this limit through a combination of novel physical processes and new materials and concepts in organic and inorganic systems. Some examples of semi-empirical modelling in the field are reviewed, in particular for multispectral solar cells on silicon (french ANR project MULTISOLSI). Their achievements are outlined, and the limits of these approaches shown. This introduces the main topic of this contribution, which is the use of multiscale experimental and theoretical techniques to go beyond the semi-empirical understanding of these systems. This approach has already led to great advances at modelling which have led to modelling software which is widely known. Yet a survey of the topic reveals a fragmentation of efforts across disciplines, firstly, such as organic and inorgani...

  8. Fabrication of High Efficiency, Printable Organic Light Emitting Diodes

    E-Print Network [OSTI]

    Petta, Jason

    design of OLED: Transparent Anode--ITO Glass substrate Organic layer(s) Metal Cathode Light #12;PRISMFabrication of High Efficiency, Printable Organic Light Emitting Diodes Michael AdamsMichael Adams: Design, fabricate, and characterize high efficiency OLEDs Introduction Background on OLEDs Methods

  9. Heat pipe array heat exchanger

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1987-08-25

    A heat pipe arrangement for exchanging heat between two different temperature fluids. The heat pipe arrangement is in a ounterflow relationship to increase the efficiency of the coupling of the heat from a heat source to a heat sink.

  10. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, Bruce W. (Espanola, NM)

    1993-01-01

    A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge.

  11. Remote high-temperature insulatorless heat-flux gauge

    DOE Patents [OSTI]

    Noel, B.W.

    1993-12-28

    A remote optical heat-flux gauge for use in extremely high temperature environments is described. This application is possible because of the use of thermographic phosphors as the sensing media, and the omission of the need for an intervening layer of insulator between phosphor layers. The gauge has no electrical leads, but is interrogated with ultraviolet or laser light. The luminescence emitted by the two phosphor layers, which is indicative of the temperature of the layers, is collected and analyzed in order to determine the heat flux incident on the surface being investigated. The two layers of thermographic phosphor must be of different materials to assure that the spectral lines collected will be distinguishable. Spatial heat-flux measurements can be made by scanning the light across the surface of the gauge. 3 figures.

  12. High-Temperature Components for Rankine-Cycle-Based Waste Heat...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Components for Rankine-Cycle-Based Waste Heat Recovery Systems on Combustion Engines High-Temperature Components for Rankine-Cycle-Based Waste Heat Recovery Systems on Combustion...

  13. High Efficiency of Gamma-Ray Bursts Revisited

    E-Print Network [OSTI]

    Y. C. Zou; Z. G. Dai

    2007-03-07

    Using the conservation of energy and momentum during collisions of any two shells, we consider the efficiency of gamma-ray bursts by assuming that the ejecta from the central engine are equally massive and have the same Lorentz factors. We calculate the efficiency and the final Lorentz factor of the merged whole shell for different initial diversities of Lorentz factors and for different microscopic radiative efficiency. As a result, a common high efficiency in the range of 0.1 to 0.9 is considerable, and a very high value near 100% is also reachable if the diversity of the Lorentz factors is large enough.

  14. Laclede Gas Company - Residential High Efficiency Heating Rebate...

    Broader source: Energy.gov (indexed) [DOE]

    50% of equipment cost Multi-Family Property Owners: 50 thermostat rebates, 50 furnace rebates over the life of the program Program Info Sector Name Utility Administrator...

  15. Developing Low-Cost, Highly Efficient Heat Recovery for Fuel...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    reduce carbon dioxide (CO 2 ) emissions by approximately 50% compared to a simple cycle gas turbine. Because of the electrochemical nature of fuel cells, emissions of criteria...

  16. High Efficiency Linguistics Program for Spanish (HELPS): A Cyclic Curriculum for Improving Intrinsic Spanish Language Capacity

    E-Print Network [OSTI]

    Burt, D.; Jones, T.; Silber, J.; Woods, W.

    2015-01-01

    Abstracts Issue 2015 High Efficiency Linguistics Program forIn response, the High Efficiency Linguistics Program for

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

    SciTech Connect (OSTI)

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

    2008-09-02

    The innovative research conducted for this project contributed greatly to the understanding of generating low-cost hydrogen from solar energy. The projects 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 projects 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 nations future electricity and transportation needs that is entirely home grown and carbon free. As CPV enter the nations utility markets, the opportunity for this approach to be successful is greatly increased. Amonix strongly recommends further exploration of this projects findings.

  18. Modeling and Analysis of Natural Gas and Gasoline In A High Compression Ratio High Efficiency ICRE

    Broader source: Energy.gov [DOE]

    performance of a high compression ratio (32:1 to 74:1) high efficiency (50 to 60% BTE) ICRE operating on natural gas and gasoline

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

    SciTech Connect (OSTI)

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

    2006-06-19

    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.

  20. ENTRY LOBBY ENERGY EFFICIENCY

    E-Print Network [OSTI]

    Escher, Christine

    ENTRY LOBBY ENERGY EFFICIENCY Clerestory windows provide natural day-lighting. Exterior roof SUSTAINABILITY FEATURES #12;ADMINISTRATION ENERGY EFFICIENCY High performance window glazing minimizes heat gain. Skylights provide natural day-lighting. High-efficiency lighting reduces energy costs and heat gain

  1. Stabilization void-fill encapsulation high-efficiency particulate filters

    SciTech Connect (OSTI)

    Alexander, R.G.; Stewart, W.E.; Phillips, S.J.; Serkowski, M.M.; England, J.L.; Boynton, H.C.

    1994-05-01

    This report discusses high-efficiency particulate air (HEPA) filter systems that which are contaminated with radionuclides are part of the nuclear fuel processing systems conducted by the US Department of Energy (DOE) and require replacement and safe and efficient disposal for plant safety. Two K-3 HEPA filters were removed from service, placed burial boxes, buried, and safely and efficiently stabilized remotely which reduced radiation exposure to personnel and the environment.

  2. Technology Development Roadmap for the Advanced High Temperature Reactor Secondary Heat Exchanger

    SciTech Connect (OSTI)

    P. Sabharwall; M. McCllar; A. Siahpush; D. Clark; M. Patterson; J. Collins

    2012-09-01

    This Technology Development Roadmap (TDRM) presents the path forward for deploying large-scale molten salt secondary heat exchangers (MS-SHX) and recognizing the benefits of using molten salt as the heat transport medium for advanced high temperature reactors (AHTR). This TDRM will aid in the development and selection of the required heat exchanger for: power production (the first anticipated process heat application), hydrogen production, steam methane reforming, methanol to gasoline production, or ammonia production. This TDRM (a) establishes the current state of molten salt SHX technology readiness, (b) defines a path forward that systematically and effectively tests this technology to overcome areas of uncertainty, (c) demonstrates the achievement of an appropriate level of maturity prior to construction and plant operation, and (d) identifies issues and prioritizes future work for maturing the state of SHX technology. This study discusses the results of a preliminary design analysis of the SHX and explains the evaluation and selection methodology. An important engineering challenge will be to prevent the molten salt from freezing during normal and off-normal operations because of its high melting temperature (390C for KF ZrF4). The efficient transfer of energy for industrial applications depends on the ability to incorporate cost-effective heat exchangers between the nuclear heat transport system and industrial process heat transport system. The need for efficiency, compactness, and safety challenge the capabilities of existing heat exchanger technology. The description of potential heat exchanger configurations or designs (such as printed circuit, spiral or helical coiled, ceramic, plate and fin, and plate type) were covered in an earlier report (Sabharwall et al. 2011). Significant future work, much of which is suggested in this report, is needed before the benefits and full potential of the AHTR can be realized. The execution of this TDRM will focuses research efforts on the near-term qualification, selection, or maturation strategy as detailed in this report. Development of the integration methodology feasibility study, along with research and development (R&D) needs, are ongoing tasks that will be covered in the future reports as work progresses. Section 2 briefly presents the integration of AHTR technology with conventional chemical industrial processes., See Idaho National Laboratory (INL) TEV-1160 (2011) for further details

  3. Highly Efficient Solar Thermochemical Reaction Systems

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancingR Walls - Building America Topa HighHigher|Energy

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

    E-Print Network [OSTI]

    Deng, Xunming

    1 High Efficiency and High Rate Deposited Amorphous Silicon-Based Solar Cells PHASE II Annual-Efficiency Single-Junction a-SiGe Solar Cells Section 3 Optimization of High-efficiency a-Si Top Cell Section 4. Figure 2-3 J-V curve of a single-junction a-SiGe solar cell with initial, active-area efficiency

  5. High power laser heating of low absorption materials

    SciTech Connect (OSTI)

    Olson, K.; Talghader, J.; Ogloza, A.; Thomas, J.

    2014-09-28

    A model is presented and confirmed experimentally that explains the anomalous behavior observed in continuous wave (CW) excitation of thermally isolated optics. Distributed Bragg Reflector (DBR) high reflective optical thin film coatings of HfO? and SiO?were prepared with a very low absorption, about 7 ppm, measured by photothermal common-path interferometry. When illuminated with a 17 kW CW laser for 30 s, the coatings survived peak irradiances of 13 MW/cm, on 500 ?m diameter spot cross sections. The temperature profile of the optical surfaces was measured using a calibrated thermal imaging camera for illuminated spot sizes ranging from 500 ?m to 5 mm; about the same peak temperatures were recorded regardless of spot size. This phenomenon is explained by solving the heat equation for an optic of finite dimensions and taking into account the non-idealities of the experiment. An analytical result is also derived showing the relationship between millisecond pulse to CW laser operation where (1) the heating is proportional to the laser irradiance (W/m) for millisecond pulses, (2) the heating is proportional to the beam radius (W/m) for CW, and (3) the heating is proportional to W/m? tan?(?(t)/m) in the transition region between the two.

  6. High Efficiency Burners by Retrofit - A Simple Inexpensive Way to Improve Combustion Efficiency

    E-Print Network [OSTI]

    Rogers, W. T.

    1980-01-01

    Existing direct fired process heaters and steam boilers can have their efficiencies remarkably improved, and thus cut the fuel bill, by conversion from conventional type natural draft burners to high intensity, "forced draft" type burners...

  7. Efficient Learning and Feature Selection in High Dimensional Regression

    E-Print Network [OSTI]

    Ting, Jo-Anne; D'Souza, Aaron; Vijayakumar, Sethu; Schaal, Stefan

    2010-01-01

    We present a novel algorithm for efficient learning and feature selection in high-dimensional regression problems. We arrive at this model through a modification of the standard regression model, enabling us to derive a probabilistic version...

  8. Band Alignment Engineering in Highly Efficient Planar Perovskite...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Band Alignment Engineering in Highly Efficient Planar Perovskite Solar Cells September 22, 2015 at 4:30 pm36-428 Juan-Pablo Correa-Baena COLE POLYTECHNIQUE FDRALE DE...

  9. High-Efficiency Receivers for Supercritical Carbon Dioxide Cycles...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    R&D award program. The team, led by Brayton Energy, aims to develop and demonstrate a low-cost, high-efficiency solar receiver that is compatible with s-CO2 cycles and modern...

  10. Industrial DSM: Beyond High Efficiency Lights and Motors

    E-Print Network [OSTI]

    Appelbaum, B.

    1995-01-01

    Perhaps the greatest challenge to electric utilities is the design and implementation of demand side management (DSM) programs targeted to their industrial customers. In focussing on promotion of high efficiency lighting ...

  11. High-Efficiency Receivers for Supercritical Carbon Dioxide Cycles...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    2012. progressreportsunshotbraytonfy12q4.pdf More Documents & Publications High-Efficiency Low-Cost Solar Receiver for Use in a Supercritical CO2 Recompression Cycle - FY13 Q1...

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

    SciTech Connect (OSTI)

    Not Available

    2011-06-01

    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.

  13. Conversion efficiency, scaling and global optimization of high harmonic generation

    E-Print Network [OSTI]

    Falcao-Filho, Edilson L.

    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 ...

  14. Compact and highly efficient laser pump cavity

    DOE Patents [OSTI]

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

    1999-01-01

    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.

  15. Recent developments in high-efficiency PV cells

    SciTech Connect (OSTI)

    Deb, S.

    2000-05-22

    Enormous progress has been made in recent years on a number of photovoltaic (PV) materials and devices in terms of conversion efficiencies. Ultrahigh-efficiency (>30{percent}) PV cells have been fabricated from gallium arsenide (GaAs) and its ternary alloys such as gallium indium phosphide (GaInP{sub 2}). The high-efficiency GaAs-based solar cells are being produced on a commercial scale, particularly for space applications. Efficiencies in the range of 18{percent} to 24{percent} have been achieved in traditional silicon-based devices fabricated from both multicrystalline and single-crystal materials. Major advances in efficiency have also been made on various thin-film solar cells based on amorphous silicon (aSi:H), copper gallium indium diselenide (CIGS), and cadmium telluride materials. This paper gives a brief overview of the recent progress in PV cell efficiencies based on these materials and devices.

  16. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, III, Arthur W. (Patterson, CA)

    1995-01-01

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1.times.10.sup.-9 torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating.

  17. Possible high power limitations from RF pulsed heating

    SciTech Connect (OSTI)

    Pritzkau, D.P.; Bowden, G.B.; Menegat, A.; Siemann, R.H. [Stanford Linear Accelerator Center, Stanford University, California 94309 (United States)

    1999-05-01

    One of the possible limitations to achieving high power in RF structures is damage to metal surfaces due to RF pulsed heating. Such damage may lead to degradation of RF performance. An experiment to study RF pulsed heating on copper has been developed at SLAC. The experiment consists of operating two pillbox cavities in the TE{sub 011} mode using a 50 MW X-Band klystron. The estimated temperature rise of the surface of copper is 350&hthinsp;{degree}C for a power input of 20 MW to each cavity with a pulse length of 1.5 {mu}s. Preliminary results from an experiment performed earlier are presented. A revised design for continued experiments is also presented along with relevant theory and calculations. {copyright} {ital 1999 American Institute of Physics.}

  18. Ultra high vacuum heating and rotating specimen stage

    DOE Patents [OSTI]

    Coombs, A.W. III

    1995-05-02

    A heating and rotating specimen stage provides for simultaneous specimen heating and rotating. The stage is ideally suited for operation in ultrahigh vacuum (1{times}10{sup {minus}9} torr or less), but is useful at atmosphere and in pressurized systems as well. A specimen is placed on a specimen holder that is attached to a heater that, in turn, is attached to a top housing. The top housing is rotated relative to a bottom housing and electrically connected thereto by electrically conductive brushes. This stage is made of materials that are compatible with UHV, able to withstand high temperatures, possess low outgassing rates, are gall and seize resistant, and are able to carry substantial electrical loading without overheating. 5 figs.

  19. Commercial HVAC and Water-Heating Equipment Minimum Efficiency Standards in the United States

    SciTech Connect (OSTI)

    Nasseri, Cyrus H.; Somasundaram, Sriram

    2001-08-01

    ABSTRACT In 1992, Federal legislation mandated that the U.S. Department of Energy (DOE) set the efficiency levels in the then-current ASHRAE Standard 90.1 as mandatory minimums for heating, ventilating, and air-conditioning (HVAC) and service water-heating (SWH) equipment sold in the U.S. market, as well as a process for revising the minimum equipment efficiency standards to comply with requirements in an updated Standard 90.1. Because Standard 90.1 was updated in October 1999 (Standard 90.1-1999), DOE is now undertaking a rulemaking process for these equipment categories. In January 2001, DOE published a final rule adopting Standard 90.1-1999 levels as uniform national standards for 18 product categories of commercial HVAC and SWH equipment. For 11 other categories of commercial products, DOE has signaled its intention to consider more stringent standards than those adopted by the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE). DOE has now initiated a formal rulemaking process to further analyze these equipment categories.

  20. High SO(2) Removal Efficiency Testing.

    SciTech Connect (OSTI)

    Blythe, G.

    1997-10-22

    On the base program, testing was completed at the Tampa Electric Company`s (TECo`s) Big Bend Station in November 1992. The upgrade option tested was DBA additive. Additional testing was conducted at this site during the previous quarter (April through June 1997). Results from that testing were presented in the Technical Progress Report dated July 1997. For Option I, at the Hoosier Energy Merom Station, results from another program co-funded by the Electric Power Research Institute (EPRI) and the National Rural Electric Cooperative Association have been combined with results from DOE-funded testing. Three upgrade options have been tested: DBA additive, sodium formate additive, and high pH set-point operation. All testing was completed by November 1992. There were no activities for this site during the current quarter. Option II involved testing at the Southwestern Electric Power Company Pirkey Station. Both sodium formate and DBA additives were tested as potential upgrade options. All of the testing at this site was completed by May 1993. On Option III, for testing at the PSI Energy Gibson Station, testing with sodium formate additive was completed in early October 1993, and a DBA additive performance and consumption test was completed in March of 1994. There were no efforts for this site during the current quarter. Option IV is for testing at the Duquesne Light Elrama Station. The FGD system employs magnesium-enhanced lime reagent and venturi absorber modules. An EPRI-funded model evaluation of potential upgrade options for this FGD system, along with a preliminary economic evaluation, determined that the most attractive upgrade options for this site were to increase thiosulfate ion concentrations in the FGD system liquor to lower oxidation percentages.

  1. Wound tube heat exchanger

    DOE Patents [OSTI]

    Ecker, Amir L. (Duncanville, TX)

    1983-01-01

    What is disclosed is a wound tube heat exchanger in which a plurality of tubes having flattened areas are held contiguous adjacent flattened areas of tubes by a plurality of windings to give a double walled heat exchanger. The plurality of windings serve as a plurality of effective force vectors holding the conduits contiguous heat conducting walls of another conduit and result in highly efficient heat transfer. The resulting heat exchange bundle is economical and can be coiled into the desired shape. Also disclosed are specific embodiments such as the one in which the tubes are expanded against their windings after being coiled to insure highly efficient heat transfer.

  2. Measured heating system efficiency retrofits in eight manufactured (HUD-code) homes

    SciTech Connect (OSTI)

    Siegel, J.; Davis, B.; Francisco, P.; Palmiter, L.

    1998-07-01

    This report presents the results of field measurements of heating efficiency performed on eight all-electric manufactured homes sited in the Pacific Northwest with forced-air distribution systems. These homes, like more than four million existing manufactured homes in the US, were constructed to thermal specifications that were mandated by the US Department of Housing and Urban Development in 1976. The test protocol compares real-time measurements of furnace energy usage with energy usage during periods when zonal heaters heat the homes to the same internal temperature. By alternating between the furnace and zonal heaters on 2 hour cycles, a short-term coheat test is performed. Additional measurements, including blower door and duct tightness tests, are conducted to measure and characterize the home's tightness and duct leakage so that coheat test results might be linked to other measures of building performance. The testing was done at each home before and after an extensive duct sealing retrofit was performed. The average pre-retrofit system efficiency for these homes was 69%. After the retrofit, the average system efficiency increased to 83%. The average simple payback period for the retrofits ranges from 1 to 5 years in Western Oregon and 1 to 3 years in colder Eastern Oregon.

  3. High Energy Density Thermal Batteries: Thermoelectric Reactors for Efficient Automotive Thermal Storage

    SciTech Connect (OSTI)

    2011-11-15

    HEATS Project: Sheetak is developing a new HVAC system to store the energy required for heating and cooling in EVs. This system will replace the traditional refrigerant-based vapor compressors and inefficient heaters used in todays EVs with efficient, light, and rechargeable hot-and-cold thermal batteries. The high energy density thermal batterywhich does not use any hazardous substancescan be recharged by an integrated solid-state thermoelectric energy converter while the vehicle is parked and its electrical battery is being charged. Sheetaks converters can also run on the electric battery if needed and provide the required cooling and heating to the passengerseliminating the space constraint and reducing the weight of EVs that use more traditional compressors and heaters.

  4. Coupled Model for Heat and Water Transport in a High Level Waste...

    Energy Savers [EERE]

    Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt Coupled Model for Heat and Water Transport in a High Level Waste Repository in Salt This report...

  5. Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application to

    E-Print Network [OSTI]

    Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application;#12;Cryogenic Heat Pipe for Cooling High Temperature Superconductors with Application to Electromagnetic Superconductors with Application to Electromagnetic Formation Flight Satellites by Daniel W. Kwon Submitted

  6. Fabrication and Design Aspects of High-Temperature Compact Diffusion Bonded Heat Exchangers

    SciTech Connect (OSTI)

    Mylavarapu, Sai K.; Sun, Xiaodong; Christensen, Richard N.; Glosup, Richard E.; Unocic, Raymond R

    2012-01-01

    The very high temperature reactor (VHTR), using gas-cooled reactor technology, is one of the six reactor concepts selected by the Generation IV International Forum and is anticipated to be the reactor type for the next generation nuclear plant (NGNP). In this type of reactor with an indirect power cycle system, a high-temperature and high integrity intermediate heat exchanger (IHX) with high effectiveness is required to efficiently transfer the core thermal output to secondary fluid for electricity production, process heat, or hydrogen cogeneration. The current Technology Readiness Level status issued by NGNP to all components associated with the IHX for reactor core outlet temperatures of 750-800oC is 3 on a scale of 1 to 10 with 10 being the most ready. At present, there is no proven high-temperature IHX concept for VHTRs. Amongst the various potential IHX concepts available, diffusion bonded heat exchangers (henceforth called printed circuit heat exchangers, or PCHEs) appear promising for NGNP applications. The design and fabrication of this key component of NGNP is the primary focus of this paper. In the current study, two PCHEs were fabricated using Alloy 617 plates and will be experimentally investigated for their thermal-hydraulic performance in a high-temperature helium test facility (HTHF). The HTHF was primarily designed and constructed to test the thermal-hydraulic performance of PCHEs The test facility is primarily of Alloy 800H construction and is designed to facilitate experiments at temperatures and pressures up to 800oC and 3 MPa, respectively. The PCHE fabrication related processes, i.e., photochemical machining and diffusion bonding are briefly discussed for Alloy 617 plates. Diffusion bonding of Alloy 617 plates with and without a Ni interlayer is discussed. Furthermore, preliminary microstructural and mechanical characterization studies of representative diffusion bonded Alloy 617 specimens are presented.

  7. Study of the design Method of an Efficient Ground Source Heat Pump Thermal Source System in a Cold Area

    E-Print Network [OSTI]

    Shu, H.; Duanmu, L.; Hua, R.; Zou, Y.; Du, G.

    2006-01-01

    The ground source heat pump (GSHP) system-an energy efficiency and environment friendly system-is becoming popular in many parts of China. However, an imbalance usually exists between the annual heat extracted from and rejected to the ground due...

  8. Swimming Pool Heating | Department of Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Swimming Pool Heating Swimming Pool Heating June 15, 2012 - 6:11pm Addthis You can reduce the cost of heating your swimming pool by installing a high-efficiency or solar heater,...

  9. Natural Refrigerant High-Performance Heat Pump for Commercial...

    Broader source: Energy.gov (indexed) [DOE]

    (DE-FOA-0000823) Project Objective This project aims to develop a regenerative air source heat pump for commercial and industrial heating, ventilation, and air conditioning (HVAC)...

  10. Low and high Temperature Dual Thermoelectric Generation Waste Heat Recovery System for Light-Duty Vehicles

    Broader source: Energy.gov [DOE]

    Developing a low and high temperature dual thermoelectric generation waste heat recovery system for light-duty vehicles.

  11. High field, high efficiency terahertz pulse generation by optical rectification

    E-Print Network [OSTI]

    Huang, Wenqian Ronny

    2014-01-01

    The great difficulty of producing high intensity radiation in the terahertz (THz) spectral region by conventional electronics has stimulated interest in development of sources based on photonics. Optical rectification in ...

  12. Emerging High-Efficiency Low-Cost Solar Cell Technologies

    E-Print Network [OSTI]

    McGehee, Michael

    J. of Photovoltaics, 2 (2012) p. 303. Si GaAs #12;Why thin film GaAs;Gallium Arsenide The 1.4 eV band gap is ideal for solar cells. High quality films are grownEmerging High-Efficiency Low-Cost Solar Cell Technologies Mike McGehee Materials Science

  13. High-Performance Refrigerator Using Novel Rotating Heat Exchanger |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartmentHigh-EfficiencyPatrick HughesbyDepartment

  14. High-Efficiency Nitride-Based Photonic Crystal Light Sources

    Broader source: Energy.gov [DOE]

    The University of California Santa Barbara (UCSB) is maximizing the efficiency of a white LED by enhancing the external quantum efficiency using photonic crystals to extract light that would normally be confined in a conventional structure. Ultimate efficiency can only be achieved by looking at the internal structure of light. To do this, UCSB is focusing on maximizing the light extraction efficiency and total light output from light engines driven by Gallium Nitride (GaN)-based LEDs. The challenge is to engineer large overlap (interaction) between modes and photonic crystals. The project is focused on achieving high extraction efficiency in LEDs, controlled directionality of emitted light, integrated design of vertical device structure, and nanoscale patterning of lateral structure.

  15. High temperature solid lubricant materials for heavy duty and advanced heat engines

    SciTech Connect (OSTI)

    DellaCorte, C.; Wood, J.C.

    1994-10-01

    Advanced engine designs incorporate higher mechanical and thermal loading to achieve efficiency improvements. This approach often leads to higher operating temperatures of critical sliding elements (e.g. piston ring/cylinder wall contacts and valve guides) which compromise the use of conventional and even advanced synthetic liquid lubricants. For these applications solid lubricants must be considered. Several novel solid lubricant composites and coatings designated PS/PM200 have been employed to dry and marginally oil lubricated contacts in advanced heat engines. These applications include cylinder kits of heavy duty diesels, and high temperature sterling engines, sidewall seals of rotary engines and various exhaust valve and exhaust component applications. The following paper describes the tribological and thermophysical properties of these tribomaterials and reviews the results of applying them to engine applications. Other potential tribological materials and applications are also discussed with particular emphasis to heavy duty and advanced heat engines.

  16. Atmos Energy- Natural Gas and Weatherization Efficiency Program

    Broader source: Energy.gov [DOE]

    Atmos Energy provides rebates to residential and commercial for natural gas heating equipment through the Kentucky High Efficiency Rebate Program. When Atmos Receives the Kentucky High-Efficiency...

  17. High Efficiency Solar Power via Separated Photo and Voltaic Pathways

    SciTech Connect (OSTI)

    Michael J. Naughton

    2009-02-17

    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 nations 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.

  18. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    Performance of ground source heat pump system in a near-zerosimulation tool for ground- source heat pump system designflow systems and ground source heat pump systems Abstract

  19. High Thermal Conductivity Polymer Composites for Low-Cost Heat...

    Broader source: Energy.gov (indexed) [DOE]

    Aerospace Heat recovery at moderate temperatures Benefits Lower cost Lightweight Corrosion resistance Multifunctionality Transition and...

  20. EVALUATION OF A LOW FRICTION - HIGH EFFICIENCY ROLLER BEARING ENGINE

    SciTech Connect (OSTI)

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

    2009-06-30

    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 teams 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.

  1. Development and Demonstration of a New Generation High Efficiency 10kW Stationary Fuel Cell System

    SciTech Connect (OSTI)

    Howell, Thomas Russell

    2013-04-30

    The overall project objective is to develop and demonstrate a polymer electrolyte membrane fuel cell combined heat and power (PEMFC CHP) system that provides the foundation for commercial, mass produced units which achieve over 40% electrical efficiency (fuel to electric conversion) from 50-100% load, greater than 70% overall efficiency (fuel to electric energy + usable waste heat energy conversion), have the potential to achieve 40,000 hours durability on all major process components, and can be produced in high volumes at under $400/kW (revised to $750/kW per 2011 DOE estimates) capital cost.

  2. High efficiency III-nitride light-emitting diodes

    DOE Patents [OSTI]

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

    2013-05-28

    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.

  3. Glass Strengthening via High-Intensity Plasma-Arc Heating

    SciTech Connect (OSTI)

    Wereszczak, Andrew A; Harper, David C; Duty, Chad E; Patel, P

    2010-01-01

    The use of a high-intensity plasma-arc lamp was used to irradiate the surface of soda-lime silicate glass tiles to determine if an increase in strength could be achieved. The lamp had a power density of 3500 W/cm2, a processing area of 1 cm x 10 cm, irradiated near-infrared heating at a wavelength between 0.2 1.4 m, and was controlled to unidirectionally sweep across 50-mm-square tiles at a constant speed of 8 mm/s. Ring-on-ring (RoR) equibiaxial flexure and 4 pt uni-directional flexure testings of entire tiles were used to measure and compare failure stress distributions of treated and untreated glass. Even with non-optimized processing conditions, RoR failure stress increased by approximately 25% and the 4 pt bend failure stress increased by approximately 65%. Strengthening was due to a fire-polishing-like mechanism. The arc-lamp heat-treatment caused the location of the strength-limiting flaws in the 4-pt-bend tiles to change; namely, failure initiation occurred on the gage section surface for the treated glass whereas it occurred at a gage section edge for the untreated. Arc-lamp heat-treatment is attractive not only because it provides strengthening, but because it can (non-contact) process large amounts of glass quickly and inexpensively, and is a process that either a glass manufacturer or end-user can readily employ.

  4. 7-122 A solar pond power plant operates by absorbing heat from the hot region near the bottom, and rejecting waste heat to the cold region near the top. The maximum thermal efficiency that the power plant

    E-Print Network [OSTI]

    Bahrami, Majid

    7-49 7-122 A solar pond power plant operates by absorbing heat from the hot region near the bottom, and rejecting waste heat to the cold region near the top. The maximum thermal efficiency that the power plant can have is to be determined. Analysis The highest thermal efficiency a heat engine operating between

  5. The deterioration in heat transfer to fluids at supercritical pressure and high heat fluxes

    E-Print Network [OSTI]

    Shiralkar, B. S.

    1968-01-01

    At slightly supercritical pressure and in the neighborhood of the pseudo-critical temperature (defined as the temperature corresponding to the peak in specific heat at the operating pressure), the heat transfer coefficient ...

  6. High extraction efficiency ultraviolet light-emitting diode

    DOE Patents [OSTI]

    Wierer, Jonathan; Montano, Ines; Allerman, Andrew A.

    2015-11-24

    Ultraviolet light-emitting diodes with tailored AlGaN quantum wells can achieve high extraction efficiency. For efficient bottom light extraction, parallel polarized light is preferred, because it propagates predominately perpendicular to the QW plane and into the typical and more efficient light escape cones. This is favored over perpendicular polarized light that propagates along the QW plane which requires multiple, lossy bounces before extraction. The thickness and carrier density of AlGaN QW layers have a strong influence on the valence subband structure, and the resulting optical polarization and light extraction of ultraviolet light-emitting diodes. At Al>0.3, thinner QW layers (<2.5 nm are preferred) result in light preferentially polarized parallel to the QW plane. Also, active regions consisting of six or more QWs, to reduce carrier density, and with thin barriers, to efficiently inject carriers in all the QWs, are preferred.

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

    E-Print Network [OSTI]

    Pilawa-Podgurski, R. C. N.

    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 ...

  8. Heat pipe technology development for high temperature space radiator applications

    SciTech Connect (OSTI)

    Merrigan, M.A.; Keddy, E.S.; Sena, J.T.; Elder, M.G.

    1984-01-01

    Technology requirements for heat pipe radiators, potentially among the lightest weight systems for space power applications, include flexible elements, and improved specific radiator performance(kg/kW). For these applications a flexible heat pipe capable of continuous operation through an angle of 180/sup 0/ has been demonstrated. The effect of bend angle on the heat pipe temperature distribution is reviewed. An analysis of lightweight membrane heat pipe radiators that use surface tension forces for fluid containment has been conducted. The design analysis of these lightweight heat pipes is described and a potential application in heat rejection systems for space nuclear power plants outlined.

  9. Bandgap Engineering in High-Efficiency Multijunction Concentrator Cells

    SciTech Connect (OSTI)

    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.

    2005-08-01

    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.

  10. Highly efficient light management for perovskite solar cells

    E-Print Network [OSTI]

    Wang, Dong-Lin; Hou, Guo-Jiao; Zhu, Zhen-Gang; Yan, Qing-Bo; Su, Gang

    2015-01-01

    Organic-inorganic halide perovskite solar cells have enormous potential to impact the existing photovoltaic industry. As realizing a higher conversion efficiency of the solar cell is still the most crucial task, a great number of schemes were proposed to minimize the carrier loss by optimizing the electrical properties of the perovskite solar cells. Here, we focus on another significant aspect that is to minimize the light loss by optimizing the light management to gain a high efficiency for perovskite solar cells. In our scheme, the slotted and inverted prism structured SiO2 layers are adopted to trap more light into the solar cells, and a better transparent conducting oxide layer is employed to reduce the parasitic absorption. For such an implementation, the efficiency and the serviceable angle of the perovskite solar cell can be promoted impressively. This proposal would shed new light on developing the high-performance perovskite solar cells.

  11. Air flow in a high aspect ratio heat sink

    E-Print Network [OSTI]

    Allison, Jonathan Michael

    2010-01-01

    The increasing heat output of modern electronics requires concomitant advances in heat sinking technology: reductions in thermal resistance and required pumping power are necessary. This research covers the development of ...

  12. Low Cost, High Efficiency, High Pressure Hydrogen Storage

    SciTech Connect (OSTI)

    Mark Leavitt

    2010-03-31

    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 Quantums 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 systems 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.

  13. Optical Design Considerations for High Conversion Efficiency in Photovoltaics

    E-Print Network [OSTI]

    Ganapati, Vidya

    2015-01-01

    Efficiency of Best Multi-BandgapReaching Carnot Efficiency . . . . . . . . . . . . . . . . .x List of Tables Efficiency of Best Dual Bandgap

  14. Super Boiler: First Generation, Ultra-High Efficiency Firetube Boiler

    SciTech Connect (OSTI)

    2006-06-01

    This factsheet describes a research project whose goal is to develop and demonstrate a first-generation ultra-high-efficiency, ultra-low emissions, compact gas-fired package boiler (Super Boiler), and formulate a long-range RD&D plan for advanced boiler technology out to the year 2020.

  15. Design of high efficiency blowers for future aerosol applications

    E-Print Network [OSTI]

    Chadha, Raman

    2007-04-25

    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...

  16. Process Heat Exchanger Options for the Advanced High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-06-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  17. Process Heat Exchanger Options for Fluoride Salt High Temperature Reactor

    SciTech Connect (OSTI)

    Piyush Sabharwall; Eung Soo Kim; Michael McKellar; Nolan Anderson

    2011-04-01

    The work reported herein is a significant intermediate step in reaching the final goal of commercial-scale deployment and usage of molten salt as the heat transport medium for process heat applications. The primary purpose of this study is to aid in the development and selection of the required heat exchanger for power production and process heat application, which would support large-scale deployment.

  18. High Temperature Fuel Cell Tri-Generation of Power, Heat & H2...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat & H2 from Biogas High Temperature Fuel Cell Tri-Generation of Power, Heat & H2 from Biogas Success story about using waste water treatment gas for hydrogen production at UC...

  19. Heavy-Duty Engine Technology for High Thermal Efficiency at EPA...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Technology for High Thermal Efficiency at EPA 2010 Emissions Regulations Heavy-Duty Engine Technology for High Thermal Efficiency at EPA 2010 Emissions Regulations Presentation...

  20. Synergies of High-Efficiency Clean Combustion and Lean NOx Trap...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Synergies of High-Efficiency Clean Combustion and Lean NOx Trap Catalysts Synergies of High-Efficiency Clean Combustion and Lean NOx Trap Catalysts investigation of potential...

  1. Fuels and Combustion Strategies for High-Efficiency Clean-Combustion...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Combustion Strategies for High-Efficiency Clean-Combustion Engines Fuels and Combustion Strategies for High-Efficiency Clean-Combustion Engines 2012 DOE Hydrogen and Fuel Cells...

  2. Bayonet heat exchangers in heat-assisted Stirling heat pump

    SciTech Connect (OSTI)

    Yagyu, S.; Fukuyama, Y.; Morikawa, T.; Isshiki, N.; Satoh, I.; Corey, J.; Fellows, C.

    1998-07-01

    The Multi-Temperature Heat Supply System is a research project creating a city energy system with lower environmental load. This system consists of a gas-fueled internal combustion engine and a heat-assisted Stirling heat pump utilizing shaft power and thermal power in a combination of several cylinders. The heat pump is mainly driven by engine shaft power and is partially assisted by thermal power from engine exhaust heat source. Since this heat pump is operated by proportioning the two energy sources to match the characteristics of the driving engine, the system is expected to produce cooling and heating water at high COP. This paper describes heat exchanger development in the project to develop a heat-assisted Stirling heat pump. The heat pump employs the Bayonet type heat exchangers (BHX Type I) for supplying cold and hot water and (BHX Type II) for absorbing exhaust heat from the driving engine. The heat exchanger design concepts are presented and their heat transfer and flow loss characteristics in oscillating gas flow are investigated. The main concern in the BHX Type I is an improvement of gas side heat transfer and the spirally finned tubes were applied to gas side of the heat exchanger. For the BHX Type II, internal heat transfer characteristics are the main concern. Shell-and-tube type heat exchangers are widely used in Stirling machines. However, since brazing is applied to the many tubes for their manufacturing processes, it is very difficult to change flow passages to optimize heat transfer and loss characteristics once they have been made. The challenge was to enhance heat transfer on the gas side to make a highly efficient heat exchanger with fewer parts. It is shown that the Bayonet type heat exchanger can have good performance comparable to conventional heat exchangers.

  3. Prototyping Energy Efficient Thermo-Magnetic & Induction Hardening for Heat Treat & Net Shape Forming Applications

    SciTech Connect (OSTI)

    Aquil Ahmad

    2012-08-03

    Within this project, Eaton undertook the task of bringing about significant impact with respect to sustainability. One of the major goals for the Department of Energy is to achieve energy savings with a corresponding reduction in carbon foot print. The use of a coupled induction heat treatment with high magnetic field heat treatment makes possible not only improved performance alloys, but with faster processing times and lower processing energy, as well. With this technology, substitution of lower cost alloys for more exotic alloys became a possibility; microstructure could be tailored for improved magnetic properties or wear resistance or mechanical performance, as needed. A prototype commercial unit has been developed to conduct processing of materials. Testing of this equipment has been conducted and results demonstrate the feasibility for industrial commercialization.

  4. High Efficiency LED Lamp for Solid-State Lighting

    SciTech Connect (OSTI)

    James Ibbetson

    2006-12-31

    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.

  5. Energy-efficient wireless communication In this chapter we present an energy-efficient highly adaptive network

    E-Print Network [OSTI]

    Havinga, Paul J.M.

    Energy-efficient wireless communication In this chapter we present an energy-efficient highly substantial research in the hardware aspects of mobile communications energy-efficiency, such as low-power electronics, power-down modes, and energy efficient modulation. However, due to fundamental physical

  6. A Perspective on the Future of High Efficiency Engines

    SciTech Connect (OSTI)

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

    2013-01-01

    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.

  7. High Quality Down Lighting Luminaire with 73% Overall System Efficiency

    SciTech Connect (OSTI)

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

    2010-08-31

    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.

  8. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zrich, Switzerland,of ground source heat pump system in a near-zero energy

  9. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    tool for geothermal water loop heat pump systems, 9thInternational IEA Heat Pump Conference, Zrich, Switzerland,Performance of ground source heat pump system in a near-zero

  10. An Analysis of Efficiency Improvements in Residential Sized Heat Pumps, Final Report, May 1986

    E-Print Network [OSTI]

    O'Neal, D. L.; Murphy, W. E.

    1985-01-01

    The objectives of this study included: (1) development of classes of heat pumps, (2) evaluation and selection of a suitable heat pump design model, (3) characterization of suitable baseline heat pump designs, (4) selection of design options that can...

  11. Fluid-cooled heat sink with improved fin areas and efficiencies...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    VARIOUS DEVICES Abstract: The disclosure provides a fluid-cooled heat sink having a heat transfer base and a plurality of heat transfer fins in thermal communication with the...

  12. Recent Progress in the Development of High Efficiency Thermoelectrics...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Waste Heat Power Generation Quantum Well Thermoelectrics and Waste Heat Recovery Scale Up of SiSi0.8GE0.2 and B4CB9C Superlattices for Harvesting of Waste Heat in Diesel Engines...

  13. Advanced Klystrons for High Efficiency Accelerator Systems - Final Report

    SciTech Connect (OSTI)

    Read, Michael; Ives, Robert Lawrence

    2014-03-26

    This program explored tailoring of RF pulses used to drive accelerator cavities. Simulations indicated that properly shaping the pulse risetime to match accelerator cavity characteristics reduced reflected power and increased total efficiency. Tailoring the pulse requires a high power, gridded, klystron to shape the risetime while also controlling the beam current. The Phase I program generated a preliminary design of a gridded electron gun for a klystron producing 5-10 MW of RF power. This required design of a segmented cathode using Controlled Porosity Reservoir cathodes to limit power deposition on the grid. The program was successful in computationally designing a gun producing a high quality electron beam with grid control. Additional analysis of pulse tailoring indicated that technique would only be useful for cavity drive pulses that were less than approximately 2-3 times the risetime. Otherwise, the efficiency gained during the risetime of the pulse became insignificant when considering the efficiency over the entire pulse. Consequently, it was determined that a Phase II program would not provide sufficient return to justify the cost. Never the less, other applications for a high power gridded gun are currently being pursued. This klystron, for example, would facilitate development inverse Comptom x-ray sources by providing a high repetition rate (10 -100 kHz) RF source.

  14. Residential Multi-Function Gas Heat Pump: Efficient Engine-Driven...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    will develop hardware and software for engine and system controls for a residential gas heat pump system that will provide space cooling, heating, and hot water. Various...

  15. Generation of High Efficiency Longitudinally Polarized Beam using High NA Lens Axicon and Dedicated Phase Filter

    SciTech Connect (OSTI)

    Rajesh, K. B.; Mohankumar, R.; Prathibajanet, C. Amala; Pillai, T. V. S. [Department of Physics, Anna University of Technology Tirunelveli (India); Jaroszewicz, Z. [Institute of Applied Optics, Department of Physical Optics, Warsaw (Poland)

    2011-10-20

    We propose to use pure phase filter in combination with high NA lens axicon to achieve high efficient longitudinally polarized beam with a subwavelength spot size and large depth of focus using hyper geometric Gaussian beam. Using this system, the spot size is reduced to 0.392 {lambda} and the depth of focus is increased to 7 {lambda}. The efficiency of such system is found to be 87%. This high efficient longitudinally polarized beam generated by hyper geometric Gaussian beam is useful for most of the near-field optics applications.

  16. High-efficiency solar cell and method for fabrication

    DOE Patents [OSTI]

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

    1999-01-01

    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).

  17. Test Program for High Efficiency Gas Turbine Exhaust Diffuser

    SciTech Connect (OSTI)

    Norris, Thomas R.

    2009-12-31

    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.

  18. High-efficiency solar cell and method for fabrication

    DOE Patents [OSTI]

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

    1999-08-31

    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.

  19. High-efficiency power supplies for home computers and servers Google Inc. ~ September 2006

    E-Print Network [OSTI]

    Cortes, Corinna

    ________________________________________________________________________ High-efficiency power supplies for home computers and servers Google Inc. ~ September 2006 p. 1 High-efficiency power supplies queries, so energy conservation and efficiency are important to us. For several years we've been

  20. Direct Drive Heavy-Ion-Beam Inertial Fusion at High Coupling Efficiency

    E-Print Network [OSTI]

    Logan, B. Grant

    2008-01-01

    Fusion at High Coupling Efficiency B.G. Logan 1, L.J.fusion at high coupling efficiency B. G. Logan , L . J.Issues with coupling efficiency, beam illumination symmetry

  1. High-Performance Refrigerator Using Novel Rotating Heat Exchanger...

    Energy Savers [EERE]

    Cooler relative to current heat exchanger technology are additional refrigerated space, noise reduction, and fouling reduction. Additional refrigerated volume realized by the more...

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

    SciTech Connect (OSTI)

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

    2005-01-01

    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.

  3. High resolution PET breast imager with improved detection efficiency

    DOE Patents [OSTI]

    Majewski, Stanislaw

    2010-06-08

    A highly efficient PET breast imager for detecting lesions in the entire breast including those located close to the patient's chest wall. The breast imager includes a ring of imaging modules surrounding the imaged breast. Each imaging module includes a slant imaging light guide inserted between a gamma radiation sensor and a photodetector. The slant light guide permits the gamma radiation sensors to be placed in close proximity to the skin of the chest wall thereby extending the sensitive region of the imager to the base of the breast. Several types of photodetectors are proposed for use in the detector modules, with compact silicon photomultipliers as the preferred choice, due to its high compactness. The geometry of the detector heads and the arrangement of the detector ring significantly reduce dead regions thereby improving detection efficiency for lesions located close to the chest wall.

  4. Differential heating: A versatile method for thermal conductivity measurements in high-energy-density matter

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Ping, Y.; Fernandez-Panella, A.; Sio, H.; Correa, A.; Shepherd, R.; Landen, O.; London, R. A.; Sterne, P. A.; Whitley, H. D.; Fratanduono, D.; et al

    2015-09-04

    We propose a method for thermal conductivity measurements of high energy density matter based on differential heating. A temperature gradient is created either by surface heating of one material or at an interface between two materials by different energy deposition. The subsequent heat conduction across the temperature gradient is observed by various time-resolved probing techniques. Conceptual designs of such measurements using laser heating, proton heating, and x-ray heating are presented. As a result, the sensitivity of the measurements to thermal conductivity is confirmed by simulations.

  5. Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone

    E-Print Network [OSTI]

    Yakovlev, Vadim

    Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone Shawn M (electromagnetic and thermal) modeling to cover practically valuable scenarios of hybrid (heat radiation is applied to the process of hybrid heating of cylindrical samples of limestone in Ceralink's MAT TM kiln

  6. Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped Emmanuel Rousseau

    E-Print Network [OSTI]

    Paris-Sud XI, Universit de

    Radiative heat transfer at nanoscale mediated by surface plasmons for highly doped silicon the role of surface plasmons for nanoscale radiative heat transfer between doped silicon surfaces. We derive a new accurate and closed-form expression of the radiative near- field heat transfer. We also

  7. A TWO-PHASE HEAT SPREADER FOR COOLING HIGH HEAT FLUX SOURCES Mitsuo Hashimoto, Hiroto Kasai, Yuichi Ishida, Hiroyuki Ryoson, a

    E-Print Network [OSTI]

    -power lasers, high-intensity light-emitting diodes (LEDs), and semiconductor power devices. The heat spreader

  8. Highly efficient electron vortex beams generated by nanofabricated phase holograms

    SciTech Connect (OSTI)

    Grillo, Vincenzo; Mafakheri, Erfan; Frabboni, Stefano

    2014-01-27

    We propose an improved type of holographic-plate suitable for the shaping of electron beams. The plate is fabricated by a focused ion beam on a silicon nitride membrane and introduces a controllable phase shift to the electron wavefunction. We adopted the optimal blazed-profile design for the phase hologram, which results in the generation of highly efficient (25%) electron vortex beams. This approach paves the route towards applications in nano-scale imaging and materials science.

  9. OSRAM SYLVANIA Develops High-Efficiency LED Troffer Replacement

    Broader source: Energy.gov [DOE]

    With the help of DOE funding, OSRAM SYLVANIA is developing a high-efficiency LED 2'x2' troffer replacement that is expected to be commercially available in the spring of 2012 and to be cost-competitive with existing troffers of that size. It is projected to have a light output of up to 4,000 lumens, an efficacy of more than 100 lm/W, and a CCT of 3500K.

  10. High-Efficiency Parking Lighting in Federal Facilities

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartmentHigh-Efficiency Parking Lighting in

  11. High-Efficiency Receivers for Supercritical Carbon Dioxide Cycles

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartmentHigh-Efficiency Parking Lighting

  12. High-Efficiency Window Air Conditioners - Building America Top Innovation |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartmentHigh-Efficiency Parking

  13. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    Comparison of energy efficiency between variable refrigeranttheir superior energy efficiency. The variable refrigerantfew studies reporting the energy efficiency of VRF systems

  14. High efficiency of collisional Penrose process requires heavy particle production

    E-Print Network [OSTI]

    Kota Ogasawara; Tomohiro Harada; Umpei Miyamoto

    2015-10-31

    The center-of-mass energy of two particles can become arbitrarily large if they collide near the event horizon of an extremal Kerr black hole, which is called the Ba$\\rm \\tilde n$ados-Silk-West (BSW) effect. We consider such a high-energy collision of two particles which started from infinity and follow geodesics in the equatorial plane and investigate the energy extraction from such a high-energy particle collision and the production of particles in the equatorial plane. We analytically show that, on the one hand, if the produced particles are as massive as the colliding particles, the energy-extraction efficiency is bounded by $2.19$ approximately. On the other hand, if a very massive particle is to be produced as a result of the high-energy collision, which has negative energy and necessarily falls into the black hole, the upper limit of the energy-extraction efficiency is increased to $(2+\\sqrt{3})^2 \\simeq 13.9$. Thus, higher efficiency of the energy extraction, which is typically as large as 10, provides strong evidence for the production of a heavy particle.

  15. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    E-Print Network [OSTI]

    Singer, Brett C.

    2010-01-01

    operation with energy efficiency in building systems. X X Xoperation with energy efficiency in building systems. 10.3.for Energy Efficiency and Renewable Energy, Building

  16. High Efficiency Motors for Refrigerated Open Display Cases

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh EfficiencyEnergyHigh

  17. Large-dimension, high-ZT Thermoelectric Nanocomposites for High...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Large-dimension, high-ZT Thermoelectric Nanocomposites for High-Power High-efficiency Waste Heat Recovery for Electricity Generation Large-dimension, high-ZT Thermoelectric...

  18. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  19. High Performance Trays and Heat Exchangers in Heat Pumped Distillation Columns

    E-Print Network [OSTI]

    Wisz, M. W.; Antonelli, R.; Ragi, E. G.

    1981-01-01

    exchangers and distillation trays permits additional energy savings by lower reboiler temperature differences, and reduced reflux requirements for a fixed column height, due to closer tray spacings. This paper surveys the heat pump systems currently...

  20. Heat transfer and pressure drop data for high heat flux densities to water at high subcritical pressures

    E-Print Network [OSTI]

    Rohsenow, Warren M.

    1951-01-01

    Local surface ooeffioients of heat t-ansfer, overall pressure drop data and mean friction factor are presented for heat flamms up to 3.52106 BtuAr ft2 for water flowing in a nickel tabe isder the following conditions: mass ...

  1. High efficiency rare-earth emitter for thermophotovoltaic applications

    SciTech Connect (OSTI)

    Sakr, E. S.; Zhou, Z.; Bermel, P., E-mail: pbermel@purdue.edu [Birck Nanotechnology Center, School of Electrical and Computer Engineering, Purdue University, 1205 W. State St., West Lafayette, Indiana 47907 (United States)

    2014-09-15

    In this work, we propose a rare-earth-based ceramic thermal emitter design that can boost thermophotovoltaic (TPV) efficiencies significantly without cold-side filters at a temperature of 1573?K (1300?C). The proposed emitter enhances a naturally occurring rare earth transition using quality-factor matching, with a quarter-wave stack as a highly reflective back mirror, while suppressing parasitic losses via exponential chirping of a multilayer reflector transmitting only at short wavelengths. This allows the emissivity to approach the blackbody limit for wavelengths overlapping with the absorption peak of the rare-earth material, while effectively reducing the losses associated with undesirable long-wavelength emission. We obtain TPV efficiencies of 34% using this layered design, which only requires modest index contrast, making it particularly amenable to fabrication via a wide variety of techniques, including sputtering, spin-coating, and plasma-enhanced chemical vapor deposition.

  2. Electrically Heated High Temperature Incineration of Air Toxics

    E-Print Network [OSTI]

    Agardy, F. J.; Wilcox, J. B.

    1990-01-01

    In-Process Technology has placed a prototype of its patented, electrically heated, packed-bed air toxics oxidizer at a northern California chemical plant. This thermal oxidizer is capable of handling a wide range of chlorinated and non...

  3. Ly? heating of inhomogeneous high-redshift intergalactic medium

    SciTech Connect (OSTI)

    Oklop?i?, Antonija; Hirata, Christopher M., E-mail: oklopcic@astro.caltech.edu [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MC 249-17, 1200 East California Boulevard, Pasadena, CA 91125 (United States)

    2013-12-20

    The intergalactic medium (IGM) prior to the epoch of reionization consists mostly of neutral hydrogen gas. Lyman-? (Ly?) photons produced by early stars resonantly scatter off hydrogen atoms, causing energy exchange between the radiation field and the gas. This interaction results in moderate heating of the gas due to the recoil of the atoms upon scattering, which is of great interest for future studies of the pre-reionization IGM in the H I 21 cm line. We investigate the effect of this Ly? heating in the IGM with linear density, temperature, and velocity perturbations. Perturbations smaller than the diffusion length of photons could be damped due to heat conduction by Ly? photons. The scale at which damping occurs and the strength of this effect depend on various properties of the gas, the flux of Ly? photons, and the way in which photon frequencies are redistributed upon scattering. To find the relevant length scale and the extent to which Ly? heating affects perturbations, we calculate the gas heating rates by numerically solving linearized Boltzmann equations in which scattering is treated by the Fokker-Planck approximation. We find that (1) perturbations add a small correction to the gas heating rate, and (2) the damping of temperature perturbations occurs at scales with comoving wavenumber k ? 10{sup 4} Mpc{sup 1}, which are much smaller than the Jeans scale and thus unlikely to substantially affect the observed 21 cm signal.

  4. Device and method for electron beam heating of a high density plasma

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high density plasma in a small localized region. A relativistic electron beam generator produces a high voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target plasma is ionized prior to application of the electron beam by means of a laser or other preionization source. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region within the high density plasma target.

  5. Institute for High Heat Flux Removal (IHHFR). Phases I, II, and III

    SciTech Connect (OSTI)

    Boyd, Ronald D.

    2014-08-31

    The IHHFR focused on interdisciplinary applications as it relates to high heat flux engineering issues and problems which arise due to engineering systems being miniaturized, optimized, or requiring increased high heat flux performance. The work in the IHHFR focused on water as a coolant and includes: (1) the development, design, and construction of the high heat flux flow loop and facility; (2) test section development, design, and fabrication; and, (3) single-side heat flux experiments to produce 2-D boiling curves and 3-D conjugate heat transfer measurements for single-side heated test sections. This work provides data for comparisons with previously developed and new single-side heated correlations and approaches that address the single-side heated effect on heat transfer. In addition, this work includes the addition of single-side heated circular TS and a monoblock test section with a helical wire insert. Finally, the present work includes: (1) data base expansion for the monoblock with a helical wire insert (only for the latter geometry), (2) prediction and verification using finite element, (3) monoblock model and methodology development analyses, and (4) an alternate model development for a hypervapotron and related conjugate heat transfer controlling parameters.

  6. Efficient Photo-heating Algorithms in Time-dependent Photo-ionization Simulations

    E-Print Network [OSTI]

    Lee, Kai-Yan; Lundqvist, Peter

    2015-01-01

    We present an extension to the time-dependent photo-ionization code C$^2$-Ray to calculate photo-heating in an efficient and accurate way. In C$^2$-Ray, the thermal calculation demands relatively small time-steps for accurate results. We describe two novel methods to reduce the computational cost associated with small time-steps, namely, an adaptive time-step algorithm and an asynchronous evolution approach. The adaptive time-step algorithm determines an optimal time-step for the next computational step. It uses a fast ray-tracing scheme to quickly locate the relevant cells for this determination and only use these cells for the calculation of the time-step. Asynchronous evolution allows different cells to evolve with different time-steps. The asynchronized clocks of the cells are synchronized at the times where outputs are produced. By only evolving cells which may require short time-steps with these short time-steps instead of imposing them to the whole grid, the computational cost of the calculation can be...

  7. Residential Multi-Function Gas Heat Pump: Efficient Engine-Driven...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    hardware and software for engine and system controls for a residential gas heat pump system that will provide space cooling, heating, and hot water. The project will build on...

  8. An Analysis of Efficiency Improvements in Residential Sized Heat Pumps and Central Air Conditioners

    E-Print Network [OSTI]

    O'Neal, D. L.; Boecker, C. L.; Penson, S. B.

    1986-01-01

    This report summarizes: (1) the performance improvements possible for central air conditioners and heat pumps using conventional design improvements, (2) the development of a methodology for estimating the seasonal performance of variable speed heat...

  9. High Power Hydrogen Injector with Beam Focusing for Plasma Heating

    SciTech Connect (OSTI)

    Deichuli, P.P.; Ivanov, A.A.; Korepanov, S.A.; Mishagin, V.V.; Sorokin, A.V.; Stupishin, N.V

    2005-01-15

    High power neutral beam injector has been developed with the atom energy of 25 keV, a current of 60 A, and several milliseconds pulse duration. Six of these injectors will be used for upgrade of the atomic injection system at central cell of a Gas Dynamic Trap (GDT) device and 2 injectors are planned for SHIP experiment.The injector ion source is based on an arc discharge plasma box. The plasma emitter is produced by a 1 kA arc discharge in hydrogen. A multipole magnetic field produced with permanent magnets at the periphery of the plasma box is used to increase its efficiency and improve homogeneity of the plasma emitter. The ion beam is extracted by a 4-electrodes ion optical system (IOS). Initial beam diameter is 200 mm. The grids of the IOS have a spherical curvature for geometrical focusing of the beam. The optimal IOS geometry and grid potentials were found with the numerical simulation to provide precise beam formation. The measured angular divergence of the beam is 0.02 rad, which corresponds to the 2.5 cm Gaussian radius of the beam profile measured at focal point.

  10. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    Thermal sensation, Climate change. Abstract A novel heated/resilience to future climate change, and serve to deepen

  11. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, Kwan H. (Naperville, IL); Ahluwalia, Rajesh K. (Burr Ridge, IL)

    1994-01-01

    A radiative heat transfer mechanism in a furnace having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits.

  12. Heat transfer mechanism with thin filaments including ceramic high temperature heat exchanger

    DOE Patents [OSTI]

    Im, K.H.; Ahluwalia, R.K.

    1994-10-18

    A radiative heat transfer mechanism in a furnace is described having burners through which pulverized coal and air are burned producing combustion gases and contaminants. A plurality of elongated conduits are positioned inside the furnace proximate to the burners generally parallel to the flow of combustion gases in the furnace. A plurality of thin filaments are inside each of the elongated hollow conduits, the filaments having diameters in the range of from about 1 micrometer to about 1,000 micrometers and having an infrared radiation cross-section sufficient to cause the filaments to heat upon exposure to infrared radiation. Blower mechanism is associated with the elongated conduits for limiting the amount of soot and ash which deposit on the conduits to preserve the radiative and convective transfer of heat energy from the combustion gases to the conduits. 7 figs.

  13. NGNP Process Heat Utilization: Liquid Metal Phase Change Heat Exchanger

    SciTech Connect (OSTI)

    Piyush Sabharwall; Mike Patterson; Vivek Utgikar; Fred Gunnerson

    2008-09-01

    One key long-standing issue that must be overcome to fully realize the successful growth of nuclear power is to determine other benefits of nuclear energy apart from meeting the electricity demands. The Next Generation Nuclear Plant (NGNP) will most likely be producing electricity and heat for the production of hydrogen and/or oil retrieval from oil sands and oil shale to help in our national pursuit of energy independence. For nuclear process heat to be utilized, intermediate heat exchange is required to transfer heat from the NGNP to the hydrogen plant or oil recovery field in the most efficient way possible. Development of nuclear reactor - process heat technology has intensified the interest in liquid metals as heat transfer media because of their ideal transport properties. Liquid metal heat exchangers are not new in practical applications. An important rational for considering liquid metals is the potential convective heat transfer is among the highest known. Thus explains the interest in liquid metals as coolant for intermediate heat exchange from NGNP. For process heat it is desired that, intermediate heat exchangers (IHX) transfer heat from the NGNP in the most efficient way possible. The production of electric power at higher efficiency via the Brayton Cycle, and hydrogen production, requires both heat at higher temperatures and high effectiveness compact heat exchangers to transfer heat to either the power or process cycle. Compact heat exchangers maximize the heat transfer surface area per volume of heat exchanger; this has the benefit of reducing heat exchanger size and heat losses. High temperature IHX design requirements are governed in part by the allowable temperature drop between the outlet and inlet of the NGNP. In order to improve the characteristics of heat transfer, liquid metal phase change heat exchangers may be more effective and efficient. This paper explores the overall heat transfer characteristics and pressure drop of the phase change heat exchanger with Na as the heat exchanger coolant. In order to design a very efficient and effective heat exchanger one must optimize the design such that we have a high heat transfer and a lower pressure drop, but there is always a trade-off between them. Based on NGNP operational parameters, a heat exchanger analysis with the sodium phase change will be presented to show that the heat exchanger has the potential for highly effective heat transfer, within a small volume at reasonable cost.

  14. High SO{sub 2} removal efficiency testing

    SciTech Connect (OSTI)

    NONE

    1995-03-10

    Tests were conducted on the Tampa Electric Company`s (TECo) Big Bend Station, Unit 4 flue gas desulfurization (FGD) system to evaluate an option for achieving high sulfur dioxide (SO{sub 2}) removal efficiencies. The option tested was the addition of dibasic acid (DBA) additive. In addition, the effectiveness of other potential options was simulated with the Electric Power Research Institute`s (EPRI) FGD PRocess Integration and Simulation Model (FGDPRISM) after it was calibrated to the system. An economic analysis was conducted to determine the cost effectiveness of each option considered.

  15. High Efficiency Combustion and Controls | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh Efficiency Cold

  16. High Efficiency Engine Systems Development and Evaluation | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh Efficiency

  17. High Efficiency Engine Systems Development and Evaluation | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHigh EfficiencyEnergy 1

  18. Simulated heat storage in a perennially ice-covered high Arctic lake: Sensitivity to climate change

    E-Print Network [OSTI]

    Vincent, Warwick F.

    . In contrast, the perennially ice-covered lakes found at high latitudes can store heat in excess of the annualSimulated heat storage in a perennially ice-covered high Arctic lake: Sensitivity to climate change conductivity and temperature profiles. They are salinity stratified and have deep thermal maxima that persist

  19. Alternatives Generation and Analysis for Heat Removal from High Level Waste Tanks

    SciTech Connect (OSTI)

    WILLIS, W.L.

    2000-06-15

    This document addresses the preferred combination of design and operational configurations to provide heat removal from high-level waste tanks during Phase 1 waste feed delivery to prevent the waste temperature from exceeding tank safety requirement limits. An interim decision for the preferred method to remove the heat from the high-level waste tanks during waste feed delivery operations is presented herein.

  20. Demonstration of a Highly Efficient Solid Oxide Fuel Cell Power System Using Adiabatic Steam Reforming and Anode Gas Recirculation

    SciTech Connect (OSTI)

    Powell, Michael R.; Meinhardt, Kerry D.; Sprenkle, Vincent L.; Chick, Lawrence A.; Mcvay, Gary L.

    2012-05-01

    Solid oxide fuel cells (SOFC) are currently being developed for a wide variety of applications because of their high efficiency at multiple power levels. Applications for SOFCs encompass a large range of power levels including 1-2 kW residential combined heat and power applications, 100-250 kW sized systems for distributed generation and grid extension, and MW-scale power plants utilizing coal. This paper reports on the development of a highly efficient, small-scale SOFC power system operating on methane. The system uses adiabatic steam reforming of methane and anode gas recirculation to achieve high net electrical efficiency. The anode exit gas is recirculated and all of the heat and water required for the endothermic reforming reaction are provided by the anode gas emerging from the SOFC stack. Although the single-pass fuel utilization is only about 55%, because of the anode gas recirculation the overall fuel utilization is up to 93%. The demonstrated system achieved gross power output of 1650 to 2150 watts with a maximum net LHV efficiency of 56.7% at 1720 watts. Overall system efficiency could be further improved to over 60% with use of properly sized blowers.

  1. New Whole-House Solutions Case Study: Testing Ductless Heat Pumps in High-Performance Affordable Housing, the Woods at Golden Given - Tacoma, Washington

    SciTech Connect (OSTI)

    2015-06-01

    The Woods is a 30-home, high- performance, energy efficient sustainable community built by Habitat for Humanity (HFH). With Support from Tacoma Public Utilities, Washington State University (part of the Building America Partnership for Improved Residential Construction) is researching the energy performance of these homes and the ductless heat pumps (DHP) they employ. This project provides Building America with an opportunity to: field test HVAC equipment, ventilation system air flows, building envelope tightness, lighting, appliance, and other input data that are required for preliminary Building Energy Optimization (BEopt) modeling and ENERGY STAR field verification; analyze cost data from HFH and other sources related to building-efficiency measures that focus on the DHP/hybrid heating system and heat recovery ventilation system; evaluate the thermal performance and cost benefit of DHP/hybrid heating systems in these homes from the perspective of homeowners; compare the space heating energy consumption of a DHP/electric resistance (ER) hybrid heating system to that of a traditional zonal ER heating system; conduct weekly "flip-flop tests" to compare space heating, temperature, and relative humidity in ER zonal heating mode to DHP/ER mode.

  2. Thin Film Packaging Solutions for High Efficiency OLED Lighting Products

    SciTech Connect (OSTI)

    None

    2008-06-30

    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

  3. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    GSHP system is more energy efficient than the air-source VRFGSHP system is more energy efficient than the air-source VRVintended to be as energy efficient as required by current

  4. Complex in vivo Ligation Using Homologous Recombination and High-efficiency Plasmid Rescue from Saccharomyces cerevisiae.

    E-Print Network [OSTI]

    Finnigan, GC; Thorner, J

    2015-01-01

    F, Cullin C. A simple and efficient method for direct geneIizasa E, Nagano Y. Highly efficient yeast-based in vivo DNAcapability to correctly and efficiently assemble multiple

  5. Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district

    E-Print Network [OSTI]

    Cost-efficient monitoring of water quality in district heating systems This article examines the monitoring strategy for water quality in a large Danish district heating system and makes a proposal for a technical and economic improvement. Monitoring of water quality in district heating systems is necessary

  6. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    E-Print Network [OSTI]

    Singer, Brett C.

    2010-01-01

    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 /

  7. Optical Design Considerations for High Conversion Efficiency in Photovoltaics

    E-Print Network [OSTI]

    Ganapati, Vidya

    2015-01-01

    thermophotovoltaics. In solar photovoltaics, radiation fromto the efficiency of solar photovoltaics can have largeof efficiency in solar photovoltaics, and looks at how

  8. High Water Heating Bills on Lockdown at Idaho Jail

    Broader source: Energy.gov [DOE]

    Using funds from the American Recovery and Reinvestment Act, the county is installing a solar thermal hot water system that will provide nearly 70 percent of the power required for heating 600,000 gallons of water for the jail annually.

  9. Analysis of Piston Heat Flux for Highly Complex Piston Shapes...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. p-10lee.pdf More Documents & Publications Optical...

  10. High efficiency shale oil recovery. Fourth quarterly report, October 1, 1992--December 31, 1992

    SciTech Connect (OSTI)

    Adams, D.C.

    1992-12-31

    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.

  11. High current multicharged metal ion source using high power gyrotron heating of vacuum arc plasma

    SciTech Connect (OSTI)

    Vodopyanov, A. V.; Golubev, S. V.; Khizhnyak, V. I.; Mansfeld, D. A.; Nikolaev, A. G.; Oks, E. M.; Savkin, K. P.; Vizir, A. V.; Yushkov, G. Yu.

    2008-02-15

    A high current, multi charged, metal ion source using electron heating of vacuum arc plasma by high power gyrotron radiation has been developed. The plasma is confined in a simple mirror trap with peak magnetic field in the plug up to 2.5 T, mirror ratio of 3-5, and length variable from 15 to 20 cm. Plasma formed by a cathodic vacuum arc is injected into the trap either (i) axially using a compact vacuum arc plasma gun located on axis outside the mirror trap region or (ii) radially using four plasma guns surrounding the trap at midplane. Microwave heating of the mirror-confined, vacuum arc plasma is accomplished by gyrotron microwave radiation of frequency 75 GHz, power up to 200 kW, and pulse duration up to 150 {mu}s, leading to additional stripping of metal ions by electron impact. Pulsed beams of platinum ions with charge state up to 10+, a mean charge state over 6+, and total (all charge states) beam current of a few hundred milliamperes have been formed.

  12. Boost Process Heating Efficiency, Software Tools for Industry, Industrial Technologies Program (ITP) (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2008-12-01

    This fact sheet describes how the Industrial Technologies Program Process Heating Assessment and Survey Tool (PHAST) can help industrial plants indentify opportunities to save energy.

  13. Comparison of energy efficiency between variable refrigerant flow systems and ground source heat pump systems

    E-Print Network [OSTI]

    Hong, Tainzhen

    2010-01-01

    type air-source VRF system and a GSHP system that uses single-stage scroll compressors and vertical ground loop heat exchanger (

  14. Demonstration of high efficiency elastocaloric cooling with large Delta T using NiTi wires

    SciTech Connect (OSTI)

    Cui, J; Wu, YM; Muehlbauer, J; Hwang, YH; Radermacher, R; Fackler, S; Wuttig, M; Takeuchi, I

    2012-08-13

    Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit, but its environmental footprint remains a global problem. VC refrigerants such as hydrochloroflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas emissions, and their global warming potential (GWP) is as high as 1000 times that of CO2 [Buildings Energy Data Book (Building Technologies Program, Department of Energy, 2009)]. There is an urgent need to develop an alternative high-efficiency cooling technology that is affordable and environmentally friendly [A. D. Little, Report For Office of Building Technology State and Community Programs, Department of Energy, 2001]. Here, we demonstrate that elastocaloric cooling (EC), a type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation, can have the coefficient of performance as high as 1 1, with a directly measured Delta T of 17 degrees C. The solid-state refrigerant of EC completely eliminates the use of any GWP refrigerants including HCFCs/HFCs. (C) 2012 American Institute. of Physics. [http://dx.doiorg/10.1063/1.4746257

  15. 3M: Hutchinson Plant Focuses on Heat Recovery and Cogeneration During Plant-Wide Energy-Efficiency Assessment

    SciTech Connect (OSTI)

    Not Available

    2003-06-01

    3M performed a plant-wide energy efficiency assessment at its Hutchinson, Minnesota, plant to identify energy- and cost-saving opportunities. Assessment staff developed four separate implementation packages that represented various combinations of energy-efficiency projects involving chiller consolidation, air compressor cooling improvements, a steam turbine used for cogeneration, and a heat recovery boiler for two of the plant's thermal oxidizers. Staff estimated that the plant could save 6 million kWh/yr in electricity and more than 200,000 MMBtu/yr in natural gas and fuel oil, and avoid energy costs of more than$1 million during the first year.

  16. 3M: Hutchinson Plant Focuses on Heat Recovery and Cogeneration during Plan-Wide Energy-Efficiency Assessment

    SciTech Connect (OSTI)

    2003-06-01

    3M performed a plant-wide energy efficiency assessment at its Hutchinson, Minnesota, plant to identify energy- and cost-saving opportunities. Assessment staff developed four separate implementation packages that represented various combinations of energy-efficiency projects involving chiller consolidation, air compressor cooling improvements, a steam turbine used for cogeneration, and a heat recovery boiler for two of the plant's thermal oxidizers. Staff estimated that the plant could save 6 million kWh/yr in electricity and more than 200,000 MMBtu/yr in natural gas and fuel oil, and avoid energy costs of more than $1 million during the first year.

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

    SciTech Connect (OSTI)

    Parks, II, James E; Prikhodko, Vitaly Y

    2009-01-01

    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.

  18. Production trap improvements using high-efficiency internals

    SciTech Connect (OSTI)

    Delavan, D.P.; Wilson, T.T.

    1995-10-01

    Most of the Gas-Oil Separation Plants (GOSP) in Southern Area Producing of Saudi Aramco will be producing between 40% and 75% water cuts by the turn of the century. Many GOSPs will be producing more than twice the amount of water they were originally designed for. Consequently, modifications must be made to the GOSPs so that they will have the capacity to separate and clean up these large volumes of produced water. The most attractive option is to improve the separation efficiency of the High Pressure Production Traps (HPPT) where formation water is first removed from the wellhead fluid. These traps have historically removed very little water from the wellhead fluid. However, the following modifications have proven to significantly improve the separation efficiency of the traps: double the height of the weir, and raise the oil level from 40% to 65% full; install a new inlet device to minimize the formation of foam; install coalescing and foam-breaking internals to enhance oil/water coalescing and separation and to break the foam on top of the oil layer.

  19. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

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

    1998-06-16

    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.

  20. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

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

    1996-01-01

    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.

  1. Processes for producing low cost, high efficiency silicon solar cells

    DOE Patents [OSTI]

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

    1998-06-16

    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.

  2. High SO[sub 2] removal efficiency testing

    SciTech Connect (OSTI)

    Blythe, G.

    1993-04-22

    This document provides a discussion of the technical progress on DOE-PETC Project Number AC22-92PC91338, High Efficiency SO[sub 2] Removal Testing,'' for the time period from January 1 through March 31, 1993. The project involves testing at full-scale utility flue gas desulfurization (FGD) systems to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO[sub 2] removal efficiency. The options to be evaluated primarily involve the addition of organic acid buffers to the FGD systems. The base'' project involves testing at one site, Tampa Electric Company's Big Bend Station. Up to five optional sites may be added to the program at the discretion of DOE-PETC. By March 31, 1993, four of those five options had been exercised. The options include testing at Hoosier Energy's Merom Station (Option I), Southwestern Electric Power Company's (SWEPCo) Pirkey Station (Option II), PSI Energy's Gibson Station (Option III), and Duquesne Light's Elrama Station (Option IV). The remainder of this document is divided into three sections. Section 2, Project Summary, provides a brief overview of the technical efforts on this project during the quarter. Section 3, Results, summarizes the outcome of those technical efforts. Results for the Base Program and for Options I and II are discussed in separate subsections. There are no technical results yet for Options III and IV, which were just exercised by DOE-PETC this quarter.

  3. Turning off the heat. Why America must double energy efficiency to save money and reduce global warming

    SciTech Connect (OSTI)

    Casten, T.R.

    1998-12-31

    Turning Off the Heat targets a main source of overuse of fossil fuels--the energy producers themselves who, through their government-approved monopolies have led to energy inefficiency and needless pollution. A leading authority with 20 years of experience in the development and operation of energy conversions in the development and operation of energy conversions, Thomas R. Casten clearly explains that the US and other nations of the world can, and must, double the efficiency of energy utilities. This efficiency improvement will lead to a reduction of electric prices by 30 to 40% and cut carbon dioxide emissions (a greenhouse gas) in half. Two-thirds of the fuel used to make US Electricity is wasted, resulting in higher energy prices and excess pollution. If market forces are unleased and monopolies ended, competition will save money and fuel, Casten says. Turning Off the Heat is an essential volume for policy-makers, legislators, leaders in industry, environmentalists, and concerned citizens.

  4. Macroporous TiO2 Photoanodes for High Efficiency PSI-Based Biohybrid Photovoltaics

    E-Print Network [OSTI]

    Macroporous TiO2 Photoanodes for High Efficiency PSI-Based Biohybrid Photovoltaics and efficiency of PSI-based biohybrid photovoltaics due to the high integraVon of PSI

  5. Scalable Light Module for Low-Cost, High Efficiency LED Luminaires...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Scalable Light Module for Low-Cost, High Efficiency LED Luminaires Scalable Light Module for Low-Cost, High Efficiency LED Luminaires Lead Performer: Cree, Inc. - Durham, NC DOE...

  6. Low-Temperature Combustion for High-Efficiency, Ultra-Low Emission...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Low-Temperature Combustion for High-Efficiency, Ultra-Low Emission Engines Low-Temperature Combustion for High-Efficiency, Ultra-Low Emission Engines Presentation given at DEER...

  7. High Efficiency Clean Combustion in Multi-Cylinder Light-Duty...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    D.C. ace17wagner.pdf More Documents & Publications High-Efficiency Clean Combustion in Light-Duty Multi-Cylinder Diesel Engines High Efficiency Clean Combustion in...

  8. Field Demonstration of High Efficiency Gas Heaters | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    to building occupants. Unit heaters are a major source of energy use nationally, accounting for nearly 18% of primary space heating energy use for commercial buildings, and...

  9. Emerging energy-efficient industrial technologies

    E-Print Network [OSTI]

    2000-01-01

    Brewery Waste Heat Recovery for Process Hot Water Heating. waste water treatment High efficiency/low No x burners BOF gas and sensible heat recoverywaste water treatment Dry sheet forming High Consistency forming Impulse drying BOF gas and sensible heat recovery

  10. Demonstration of High Efficiency Elastocaloric Cooling with Large Delta- T Using NiTi Wires

    SciTech Connect (OSTI)

    Cui, Jun; Wu, Yiming; Muehlbauer, Jan; Hwang, Yunho; Radermacher, Reinhard; Fackler, Sean; Wuttig, Manfred; Takeuchi, Ichiro

    2012-08-01

    Vapor compression (VC) is by far the most dominant technology for meeting all cooling and refrigeration needs around the world. It is a mature technology with the efficiency of modern compressors approaching the theoretical limit, but its envi-ronmental footprint remains a global problem. VC refrigerants such as hydrochlo-roflurocarbons (HCFCs) and hydrofluorocarbons (HFCs) are a significant source of green house gas (GHG) emissions, and their global warming potential (GWP) is as high as 1000 times that of CO2. It is expected that building space cooling and re-frigeration alone will amount to {approx} 5% of primary energy consumption and {approx}5% of all CO2 emission in U.S. in 2030 . As such, there is an urgent need to develop an al-ternative high-efficiency cooling technology that is affordable and environmentally friendly. Among the proposed candidates, magnetocaloric cooling (MC) is currently received a lot of attention because of its high efficiency. However, MC is inherently expensive because of the requirement of large magnetic field and rare earth materi-als. Here, we demonstrate an entirely new type of solid-state cooling mechanism based on the latent heat of reversible martensitic transformation. We call it elasto-caloric cooling (EC) after the superelastic transformation of austenite it utilizes. The solid-state refrigerant of EC is cost-effective, and it completely eliminates the use of any refrigerants including HCFCs/HFCs. We show that the COP (coefficient of per-formance) of a jugular EC with optimized materials can be as high as > 10 with measured {Delta}T of 17 C.

  11. Thermal hydraulic performance testing of printed circuit heat exchangers in a high-temperature helium test facility

    SciTech Connect (OSTI)

    Sai K. Mylavarapu; Xiaodong Sun; Richard E. Glosup; Richard N. Christensen; Michael W. Patterson

    2014-04-01

    In high-temperature gas-cooled reactors, such as a very high temperature reactor (VHTR), an intermediate heat exchanger (IHX) is required to efficiently transfer the core thermal output to a secondary fluid for electricity generation with an indirect power cycle and/or process heat applications. Currently, there is no proven high-temperature (750800 C or higher) compact heat exchanger technology for high-temperature reactor design concepts. In this study, printed circuit heat exchanger (PCHE), a potential IHX concept for high-temperature applications, has been investigated for their heat transfer and pressure drop characteristics under high operating temperatures and pressures. Two PCHEs, each having 10 hot and 10 cold plates with 12 channels (semicircular cross-section) in each plate are fabricated using Alloy 617 plates and tested for their performance in a high-temperature helium test facility (HTHF). The PCHE inlet temperature and pressure were varied from 85 to 390 C/1.02.7 MPa for the cold side and 208790 C/1.02.7 MPa for the hot side, respectively, while the mass flow rate of helium was varied from 15 to 49 kg/h. This range of mass flow rates corresponds to PCHE channel Reynolds numbers of 950 to 4100 for the cold side and 900 to 3900 for the hot side (corresponding to the laminar and laminar-to-turbulent transition flow regimes). The obtained experimental data have been analyzed for the pressure drop and heat transfer characteristics of the heat transfer surface of the PCHEs and compared with the available models and correlations in the literature. In addition, a numerical treatment of hydrodynamically developing and hydrodynamically fully-developed laminar flow through a semicircular duct is presented. Relations developed for determining the hydrodynamic entrance length in a semicircular duct and the friction factor (or pressure drop) in the hydrodynamic entry length region for laminar flow through a semicircular duct are given. Various hydrodynamic entrance region parameters, such as incremental pressure drop number, apparent Fanning friction factor, and hydrodynamic entrance length in a semicircular duct have been numerically estimated.

  12. temperature heat pumps applied to

    E-Print Network [OSTI]

    Oak Ridge National Laboratory

    Very high- temperature heat pumps applied to energy efficiency in industry Application of industrial heat pumps June 21 th 2012 J-L Peureux, E. Sapora, D. Bobelin EDF R&D #12;Achema 2012 Frankfurt There are thermal requirements in the industrial plant Treq Heat exchanger = Cons ~ 0 CO2 ~ -100% Treq

  13. Air-Stable High-Efficiency Solar Cells Using Improved Single-Walled Carbon Nanotube Films

    E-Print Network [OSTI]

    Maruyama, Shigeo

    1 Air-Stable High-Efficiency Solar Cells Using Improved Single-Walled Carbon Nanotube Films Kehang intensities. The high efficiency and stability demonstrated in this study make SWNT/Si solar cell very front contact KEYWORDS: Single-walled carbon nanotube, solar cell, high efficiency, stability, SWNT

  14. High Efficiency Current-Mode Class-DAmplifier with Integrated Resonator

    E-Print Network [OSTI]

    Asbeck, Peter M.

    THIF-54 High Efficiency Current-Mode Class-DAmplifier with Integrated Resonator Tsai-PiHung, Andre) amplifiers with integrated parallel LC resonator can achieve high efficiency at RF frequencies. In contrast to implement a high Q inductor in the LC resonator. An experimental CMCD amplifier with collector efficiency

  15. Northwest Energy Efficient Manufactured Housing Program: High Performance Manufactured Home Prototyping and Construction Development

    SciTech Connect (OSTI)

    Hewes, T.; Peeks, B.

    2013-11-01

    The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in the manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50 percent over typical manufactured homes produced in the northwest.

  16. Northwest Energy Efficient Manufactured Housing Program: High Performance Manufactured Home Prototyping and Construction Development

    SciTech Connect (OSTI)

    Hewes, Tom; Peeks, Brady

    2013-11-01

    The Building America Partnership for Improved Residential Construction, the Bonneville Power Administration (BPA), and Northwest Energy Works (NEW), the current Northwest Energy Efficient Manufactured Housing Program (NEEM) administrator, have been collaborating to conduct research on new specifications that would improve on the energy requirements of a NEEM home. In its role as administrator, NEW administers the technical specs, performs research and engineering analysis, implements ongoing construction quality management procedures, and maintains a central database with home tracking. This project prototyped and assessed the performances of cost-effective high performance building assemblies and mechanical systems that are not commonly deployed in the manufacturing setting. The package of measures is able to reduce energy used for space conditioning, water heating and lighting by 50% over typical manufactured homes produced in the northwest.

  17. High Temperature Variable Conductance Heat Pipes for Radioisotope Stirling Systems

    SciTech Connect (OSTI)

    Tarau, Calin; Walker, Kara L.; Anderson, William G.

    2009-03-16

    In a Stirling radioisotope system, heat must continually be removed from the GPHS modules, to maintain the GPHS modules and surrounding insulation at acceptable temperatures. Normally, the Stirling converter provides this cooling. If the Stirling engine stops in the current system, the insulation is designed to spoil, preventing damage to the GPHS, but also ending the mission. An alkali-metal Variable Conductance Heat Pipe (VCHP) is under development to allow multiple stops and restarts of the Stirling engine. The status of the ongoing effort in developing this technology is presented in this paper. An earlier, preliminary design had a radiator outside the Advanced Stirling Radioisotope Generator (ASRG) casing, used NaK as the working fluid, and had the reservoir located on the cold side adapter flange. The revised design has an internal radiator inside the casing, with the reservoir embedded inside the insulation. A large set of advantages are offered by this new design. In addition to reducing the overall size and mass of the VCHP, simplicity, compactness and easiness in assembling the VCHP with the ASRG are significantly enhanced. Also, the permanently elevated temperatures of the entire VCHP allows the change of the working fluid from a binary compound (NaK) to single compound (Na). The latter, by its properties, allows higher performance and further mass reduction of the system. Preliminary design and analysis shows an acceptable peak temperature of the ASRG case of 140 deg. C while the heat losses caused by the addition of the VCHP are 1.8 W.

  18. Anomalous specific heat in high-density QED and QCD

    E-Print Network [OSTI]

    A. Ipp; A. Gerhold; A. Rebhan

    2003-09-22

    Long-range quasi-static gauge-boson interactions lead to anomalous (non-Fermi-liquid) behavior of the specific heat in the low-temperature limit of an electron or quark gas with a leading $T\\ln T^{-1}$ term. We obtain perturbative results beyond the leading log approximation and find that dynamical screening gives rise to a low-temperature series involving also anomalous fractional powers $T^{(3+2n)/3}$. We determine their coefficients in perturbation theory up to and including order $T^{7/3}$ and compare with exact numerical results obtained in the large-$N_f$ limit of QED and QCD.

  19. Graphene Oxide Interlayers for Robust, High-Efficiency Organic Photovoltaics

    SciTech Connect (OSTI)

    Murray, Ian P.; Lou, Sylvia J.; Cote, Laura J.; Loser, Stephen; Kadleck, Cameron J.; Xu, Tao; Szarko, Jodi M.; Rolczynski, Brian S.; Johns, James E.; Huang, Jiaxing; Yu, Luping; Chen, Lin X.; Marks, Tobin J.; Hersam, Mark C. (NWU)

    2012-02-07

    Organic photovoltaic (OPV) materials have recently garnered significant attention as enablers of high power conversion efficiency (PCE), low-cost, mechanically flexible solar cells. Nevertheless, further understanding-based materials developments will be required to achieve full commercial viability. In particular, the performance and durability of many current generation OPVs are limited by poorly understood interfacial phenomena. Careful analysis of typical OPV architectures reveals that the standard electron-blocking layer, poly-3,4-ethylenedioxy-thiophene:poly(styrene sulfonate) (PEDOT:PSS), is likely a major factor limiting the device durability and possibly performance. Here we report that a single layer of electronically tuned graphene oxide is an effective replacement for PEDOT:PSS and that it significantly enhances device durability while concurrently templating a performance-optimal active layer {pi}-stacked face-on microstructure. Such OPVs based on graphene oxide exhibit PCEs as high as 7.5% while providing a 5x enhancement in thermal aging lifetime and a 20x enhancement in humid ambient lifetime versus analogous PEDOT:PSS-based devices.

  20. High-efficiency photovoltaics based on semiconductor nanostructures

    SciTech Connect (OSTI)

    Yu, Paul K.L.; Yu, Edward T.; Wang, Deli

    2011-10-31

    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.

  1. Heat treated 9 Cr-1 Mo steel material for high temperature application

    DOE Patents [OSTI]

    Jablonski, Paul D.; Alman, David; Dogan, Omer; Holcomb, Gordon; Cowen, Christopher

    2012-08-21

    The invention relates to a composition and heat treatment for a high-temperature, titanium alloyed, 9 Cr-1 Mo steel exhibiting improved creep strength and oxidation resistance at service temperatures up to 650.degree. C. The novel combination of composition and heat treatment produces a heat treated material containing both large primary titanium carbides and small secondary titanium carbides. The primary titanium carbides contribute to creep strength while the secondary titanium carbides act to maintain a higher level of chromium in the finished steel for increased oxidation resistance, and strengthen the steel by impeding the movement of dislocations through the crystal structure. The heat treated material provides improved performance at comparable cost to commonly used high-temperature steels such as ASTM P91 and ASTM P92, and requires heat treatment consisting solely of austenization, rapid cooling, tempering, and final cooling, avoiding the need for any hot-working in the austenite temperature range.

  2. High energy bursts from a solid state laser operated in the heat capacity limited regime

    DOE Patents [OSTI]

    Albrecht, Georg (Livermore, CA); George, E. Victor (Livermore, CA); Krupke, William F. (Pleasanton, CA); Sooy, Walter (Pleasanton, CA); Sutton, Steven B. (Manteca, CA)

    1996-01-01

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes.

  3. High energy bursts from a solid state laser operated in the heat capacity limited regime

    DOE Patents [OSTI]

    Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

    1996-06-11

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

  4. Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion

    SciTech Connect (OSTI)

    Per F. Peterson

    2010-03-01

    This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

  5. High-Performance Thermoelectric Devices Based on Abundant Silicide Materials for Vehicle Waste Heat Recovery

    Office of Energy Efficiency and Renewable Energy (EERE)

    Development of high-performance thermoelectric devices for vehicle waste heat recovery will include fundamental research to use abundant promising low-cost thermoelectric materials, thermal management and interfaces design, and metrology

  6. Hanford waste treatment plant Immobilized High Level Waste (IHLW) canister radiation dose rate and radiolytic heat load analysis

    SciTech Connect (OSTI)

    PIERSON, R.M.

    2003-09-02

    This document provides an analysis of anticipated radiation dose rates and heat loads for immobilized high level waste (IHW) canisters

  7. High Heat Flux Exposure Tests on 10mm Beryllium Tiles Brazed on Actively Cooled Vapotron made from CUCRZR

    E-Print Network [OSTI]

    High Heat Flux Exposure Tests on 10mm Beryllium Tiles Brazed on Actively Cooled Vapotron made from CUCRZR

  8. Optimization of Combustion Efficiency for Supplementally Fired Gas Turbine Cogenerator Exhaust Heat Receptors

    E-Print Network [OSTI]

    Waterland, A. F.

    1984-01-01

    A broad range of unique cogeneration schemes are being installed or considered for application in the process industries involving gas turbines with heat recovery from the exhaust gas. Depending on the turbine design, exhaust gases will range from...

  9. Energy-efficient comfort with a heated/cooled chair: Results from human subject tests

    E-Print Network [OSTI]

    Pasut, Wilmer; Zhang, Hui; Arens, Ed; Zhai, Yongchao

    2015-01-01

    heating and Building and Environment 2015 DOI: 10.1016/j.buildenv.2014.10.026 http://escholarship.org/uc/item/6b05q82n cooling. The floor

  10. High-Efficiency Nitride-Based Solid-State Lighting

    SciTech Connect (OSTI)

    Paul T. Fini; Shuji Nakamura

    2005-07-30

    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.

  11. Low Temperature Combustion Demonstrator for High Efficiency Clean Combustion

    SciTech Connect (OSTI)

    Ojeda, William de

    2010-07-31

    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.

  12. Project Profile: High Operating Temperature Liquid Metal Heat...

    Office of Environmental Management (EM)

    multi-target co-sputtering system to create massive compositional libraries in thin-film forms and employ high-throughput characterization methods to rapidly screen candidate...

  13. Improving Energy Efficiency by Developing Components for Distributed Cooling and Heating Based on Thermal Comfort Modeling

    Office of Energy Efficiency and Renewable Energy (EERE)

    Discusses comfort model enhancement/validation, climate system efficiency parameters and system trade off, and powertrain mode operation changes to further vehicle energy saving while preserving occupant comfort.

  14. HEATS OF COMBUSTION OF HIGH TEMPERATURE POLYMERS Richard N. Walters*, Stacey M. Hackett* and Richard E. Lyon

    E-Print Network [OSTI]

    Laughlin, Robert B.

    1 HEATS OF COMBUSTION OF HIGH TEMPERATURE POLYMERS Richard N. Walters*, Stacey M. Hackett Creek Avenue, Building C Egg Harbor Township, New Jersey 08234 ABSTRACT The heats of combustion to thermochemical calculations of the net heat of combustion from oxygen consumption and the gross heat

  15. HIGH-EFFICIENCY NITRIDE-BASED SOLID-STATE LIGHTING

    SciTech Connect (OSTI)

    Paul T. Fini; Shuji Nakamura

    2003-10-30

    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.

  16. High efficiency proportional neutron detector with solid liner internal structures

    DOE Patents [OSTI]

    Kisner, Roger Allen; Holcomb, David Eugene; Brown, Gilbert M.

    2014-08-05

    A tube-style neutron detector, a panel-style neutron detector incorporating a plurality of tube-style neutron detectors, and a panel-style neutron detector including a plurality of anode wires are provided. A plurality of channels is provided in a neutron detector such that each channel has an inner surface of a coating layer including a neutron-absorbing material. A wire anode is provided at end of each channel so that electrons generated by a charged daughter particle generated by a neutron are collected to detect a neutron-matter interaction. Moderator units can be incorporated into a neutron detector to provide improved detection efficiencies and/or to determine neutron energy spectrum. Gas-based proportional response from the neutron detectors can be employed for special nuclear material (SNM) detection. This neutron detector can provide similar performance to .sup.3He-based detectors without requiring .sup.3He and without containing toxic, flammable, or high-pressure materials.

  17. Research on stable, high-efficiency amorphous silicon multijunction modules

    SciTech Connect (OSTI)

    Ghosh, M.; DelCueto, J.: Kampas, F.; Xi, J. )

    1993-02-01

    This report describes results from the first phase of a three-phase contract for the development of stable, high-efficiency, same-band-gap, amorphous silicon (a-Si) multijunction photovoltaic (PV) modules. The program involved improving the properties of individual layers of semiconductor and non-semiconductor materials and small-area single-junction and multijunction devices, as well as the multijunction modules. The semiconductor materials research was performed on a-Si p, i, and n layers, and on microcrystalline silicon n layers. These were deposited using plasma-enhanced chemical vapor deposition. The non-semiconductor materials studied were tin oxide, for use as a transparent-conducting-oxide (TCO), and zinc oxide, for use as a back reflector and as a buffer layer between the TCO and the semiconductor layers. Tin oxide was deposited using atmospheric-pressure chemical vapor deposition. Zinc oxide was deposited using magnetron sputtering. The research indicated that the major challenge in the fabrication of a-Si multijunction PV modules is the contact between the two p-i-n cells. A structure that has low optical absorption but that also facilitates the recombination of electrons from the first p-i-n structure with holes from the second p-i-n structure is required. Non-semiconductor layers and a-Si semiconductor layers were tested without achieving the desired result.

  18. Field Demonstration of High-Efficiency Ultra-Low-Temperature...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Better Buildings Alliance Building Technologies Office Office of Energy Efficiency and Renewable Energy U.S. Department of Energy By: Rebecca Legett, Navigant Consulting, Inc....

  19. High Performance Healthcare Buildings: A Roadmap to Improved Energy Efficiency

    E-Print Network [OSTI]

    Singer, Brett C.

    2010-01-01

    needs. Include energy efficiency best practice in designand benchmarking energy use; best practices and training;of practitioners. Energy performance best practices ideally

  20. Optical Design Considerations for High Conversion Efficiency in Photovoltaics

    E-Print Network [OSTI]

    Ganapati, Vidya

    2015-01-01

    for light trapping in photovoltaics: the supercell concept,efficiency tables, Progress in Photovoltaics: Research andphotovoltaic cells, Progress in Photovoltaics: Research and

  1. High-efficiency Low Global-Warming Potential (GWP) Compressor...

    Broader source: Energy.gov (indexed) [DOE]

    417,000 Project Term: Sep 2015 - Aug 2017 Funding Opportunity: Building Energy Efficiency Frontiers and Innovation Technologies (BENEFIT) - 2015, DE-FOA-0001166 Project...

  2. High Efficiency Clean Combustion for Heavy-Duty Engine | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Innovative dual mode combustion strategy enabled by variable fuel injection offers emission reduction and efficiency improvement advantages. deer08zhang.pdf More Documents &...

  3. Greensburg Implements High-Efficiency Building Codes to Achieve...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    for incorpo- rating energy efficiency and renewable energy into building designs. The Energy Transition Initiative leverages the experiences of islands, states, and cities that...

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

    Office of Environmental Management (EM)

    work to improve the efficiency of advanced internal combustion engines for automotive, light trucks, and heavy-truck applications by 25% to 50%. However, many of these...

  5. Energy-Efficient Melting and Direct Delivery of High Quality...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    radiation and some convec- tion. These furnaces are characterized by poor thermal efficien- cies ranging from approximately 20%-45%. The Energy Efficient Isothermal Melting...

  6. ENERGY-EFFICIENT RESOURCE MANAGEMENT FOR HIGH-PERFORMANCE COMPUTING PLATFORMS

    E-Print Network [OSTI]

    Qin, Xiao

    ENERGY-EFFICIENT RESOURCE MANAGEMENT FOR HIGH-PERFORMANCE COMPUTING PLATFORMS Except where School Engineering #12;ENERGY-EFFICIENT RESOURCE MANAGEMENT FOR HIGH-PERFORMANCE COMPUTING PLATFORMS of the Requirements for the Degree of Doctor of Philosophy Auburn, Alabama August 9, 2008 #12;iii ENERGY-EFFICIENT

  7. Advanced Nanomaterials for High-Efficiency Solar Cells

    SciTech Connect (OSTI)

    Chen, Junhong

    2013-11-29

    Energy supply has arguably become one of the most important problems facing humankind. The exponential demand for energy is evidenced by dwindling fossil fuel supplies and record-high oil and gas prices due to global population growth and economic development. This energy shortage has significant implications to the future of our society, in addition to the greenhouse gas emission burden due to consumption of fossil fuels. Solar energy seems to be the most viable choice to meet our clean energy demand given its large scale and clean/renewable nature. However, existing methods to convert sun light into electricity are not efficient enough to become a practical alternative to fossil fuels. This DOE project aims to develop advanced hybrid nanomaterials consisting of semiconductor nanoparticles (quantum dots or QDs) supported on graphene for cost-effective solar cells with improved conversion efficiency for harvesting abundant, renewable, clean solar energy to relieve our global energy challenge. Expected outcomes of the project include new methods for low-cost manufacturing of hybrid nanostructures, systematic understanding of their properties that can be tailored for desired applications, and novel photovoltaic cells. Through this project, we have successfully synthesized a number of novel nanomaterials, including vertically-oriented graphene (VG) sheets, three-dimensional (3D) carbon nanostructures comprising few-layer graphene (FLG) sheets inherently connected with CNTs through sp{sup 2} carbons, crumpled graphene (CG)-nanocrystal hybrids, CdSe nanoparticles (NPs), CdS NPs, nanohybrids of metal nitride decorated on nitrogen-doped graphene (NG), QD-carbon nanotube (CNT) and QD-VG-CNT structures, TiO{sub 2}-CdS NPs, and reduced graphene oxide (RGO)-SnO{sub 2} NPs. We further assembled CdSe NPs onto graphene sheets and investigated physical and electronic interactions between CdSe NPs and the graphene. Finally we have demonstrated various applications of these nanomaterials in solar cells (both as photoanodes and counter electrodes), gas sensors, and energy storage devices. This research is potentially transformative since the availability of affordable hybrid nanostructures and their fundamental properties will enable various innovative applications of the multifunctional hybrid nanostructures and thus will accelerate new discoveries and inventions in nanoscience and nanotechnology.

  8. Effect of shear and magnetic field on the heat-transfer efficiency of convection in rotating spherical shells

    E-Print Network [OSTI]

    Yadav, Rakesh K; Christensen, Ulrich R; Duarte, Lucia; Reiners, Ansgar

    2015-01-01

    We study rotating thermal convection in spherical shells as prototype for flow in the cores of terrestrial planets, gas planets or in stars. We base our analysis on a set of about 450 direct numerical simulations of the (magneto)hydrodynamic equations under the Boussinesq approximation. The Ekman number ranges from $10^{-3}$ to $10^{-6}$. Four sets of simulations are considered: non-magnetic simulations and dynamo simulations with either free-slip or no-slip flow boundary conditions. The non-magnetic setup with free-slip boundaries generates the strongest zonal flows. Both non-magnetic simulations with no-slip flow boundary conditions and self-consistent dynamos with free-slip boundaries have drastically reduced zonal-flows. Suppression of shear leads to a substantial gain in heat-transfer efficiency, increasing by a factor of 3 in some cases. Such efficiency enhancement occurs as long as the convection is significantly influenced by rotation. At higher convective driving the heat-transfer efficiency trends t...

  9. Absorption-heat-pump system

    DOE Patents [OSTI]

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  10. HEATS: Thermal Energy Storage

    SciTech Connect (OSTI)

    2012-01-01

    HEATS Project: The 15 projects that make up ARPA-Es HEATS program, short for High Energy Advanced Thermal Storage, seek to develop revolutionary, cost-effective ways to store thermal energy. HEATS focuses on 3 specific areas: 1) developing high-temperature solar thermal energy storage capable of cost-effectively delivering electricity around the clock and thermal energy storage for nuclear power plants capable of cost-effectively meeting peak demand, 2) creating synthetic fuel efficiently from sunlight by converting sunlight into heat, and 3) using thermal energy storage to improve the driving range of electric vehicles (EVs) and also enable thermal management of internal combustion engine vehicles.

  11. Sterically Engineered Perylene Dyes for High Efficiency Oriented Fluorophore Luminescent Solar Concentrators

    E-Print Network [OSTI]

    Patrick, David L.

    Sterically Engineered Perylene Dyes for High Efficiency Oriented Fluorophore Luminescent Solar Luminescent solar concentrators (LSCs) collect and concentrate sunlight for use in solar power generation.1 or interior lighting, increasing the combined-cycle efficiency. Accordingly, LSC performance is expressed

  12. High-Efficiency, Ultra-Low Emission Combustion in a Heavy-Duty...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Efficiency, Ultra-Low Emission Combustion in a Heavy-Duty Engine via Fuel Reactivity Control High-Efficiency, Ultra-Low Emission Combustion in a Heavy-Duty Engine via Fuel...

  13. High-Efficiency Multiplex Genome Editing of Streptomyces Species Using an Engineered CRISPR/Cas System

    E-Print Network [OSTI]

    Zhao, Huimin

    High-Efficiency Multiplex Genome Editing of Streptomyces Species Using an Engineered CRISPR and of various sizes (ranging from 20 bp to 30 kb) with efficiency ranging from 70 to 100%. The designed p

  14. Webinar: Award-Winning LEEP Campaign Sites Demonstrate Big Savings in High Efficiency Parking Lighting

    Broader source: Energy.gov [DOE]

    The Lighting Energy Efficiency in Parking (LEEP) Campaign is saving nearly 45 million kilowatt-hours and $4 million annually by upgrading its partners to high efficiency lighting in over 500,000 parking spaces.

  15. Ultra Clean 1.1MW High Efficiency Natural Gas Engine Powered System

    SciTech Connect (OSTI)

    Zurlo, James; Lueck, Steve

    2011-08-31

    Dresser, Inc. (GE Energy, Waukesha gas engines) will develop, test, demonstrate, and commercialize a 1.1 Megawatt (MW) natural gas fueled combined heat and power reciprocating engine powered package. This package will feature a total efficiency > 75% and ultra low CARB permitting emissions. Our modular design will cover the 1 6 MW size range, and this scalable technology can be used in both smaller and larger engine powered CHP packages. To further advance one of the key advantages of reciprocating engines, the engine, generator and CHP package will be optimized for low initial and operating costs. Dresser, Inc. will leverage the knowledge gained in the DOE - ARES program. Dresser, Inc. will work with commercial, regulatory, and government entities to help break down barriers to wider deployment of CHP. The outcome of this project will be a commercially successful 1.1 MW CHP package with high electrical and total efficiency that will significantly reduce emissions compared to the current central power plant paradigm. Principal objectives by phases for Budget Period 1 include: Phase 1 market study to determine optimum system performance, target first cost, lifecycle cost, and creation of a detailed product specification. Phase 2 Refinement of the Waukesha CHP system design concepts, identification of critical characteristics, initial evaluation of technical solutions, and risk mitigation plans. Background

  16. Gray-box model for energy-efficient selection of set point hysteresis in heating, ventilation, air conditioning, and refrigeration controllers

    E-Print Network [OSTI]

    Bahrami, Majid

    Energy efficiency Gray-box model a b s t r a c t Many heating, ventilation, air conditioning by Heating, Ventilation, Air Conditioning, and Refrigeration (HVACR) systems [1]. HVACR energy consumption, for instance, may use up to 80% of the total energy consumed in the supermarket [3]. Moreover, Air Conditioning

  17. Waste Heat Recovery from High Temperature Off-Gases from Electric Arc Furnace

    SciTech Connect (OSTI)

    Nimbalkar, Sachin U [ORNL; Thekdi, Arvind [E3M Inc; Keiser, James R [ORNL; Storey, John Morse [ORNL

    2014-01-01

    This article presents a study and review of available waste heat in high temperature Electric Arc Furnace (EAF) off gases and heat recovery techniques/methods from these gases. It gives details of the quality and quantity of the sensible and chemical waste heat in typical EAF off gases, energy savings potential by recovering part of this heat, a comprehensive review of currently used waste heat recovery methods and potential for use of advanced designs to achieve a much higher level of heat recovery including scrap preheating, steam production and electric power generation. Based on our preliminary analysis, currently, for all electric arc furnaces used in the US steel industry, the energy savings potential is equivalent to approximately 31 trillion Btu per year or 32.7 peta Joules per year (approximately $182 million US dollars/year). This article describes the EAF off-gas enthalpy model developed at Oak Ridge National Laboratory (ORNL) to calculate available and recoverable heat energy for a given stream of exhaust gases coming out of one or multiple EAF furnaces. This Excel based model calculates sensible and chemical enthalpy of the EAF off-gases during tap to tap time accounting for variation in quantity and quality of off gases. The model can be used to estimate energy saved through scrap preheating and other possible uses such as steam generation and electric power generation using off gas waste heat. This article includes a review of the historical development of existing waste heat recovery methods, their operations, and advantages/limitations of these methods. This paper also describes a program to develop and test advanced concepts for scrap preheating, steam production and electricity generation through use of waste heat recovery from the chemical and sensible heat contained in the EAF off gases with addition of minimum amount of dilution or cooling air upstream of pollution control equipment such as bag houses.

  18. California Industrial Energy Efficiency Potential

    E-Print Network [OSTI]

    Coito, Fred; Worrell, Ernst; Price, Lynn; Masanet, Eric; Rafael Friedmann; Rufo, Mike

    2005-01-01

    Heat Recovery/Economizer Blowdown Steam Heat Recovery Upgrade Burner Efficiency Water Treatment Condensate

  19. High Operating Temperature Liquid Metal Heat Transfer Fluids (Fact Sheet)

    SciTech Connect (OSTI)

    Not Available

    2012-12-01

    The University of California, Los Angeles, the University of California, Berkeley, and Yale University is one of the 2012 SunShot CSP R&D awardees for their Multidisciplinary University Research Initiative (MURI): High Operating Temperature (HOT) Fluids. This fact sheet explains the motivation, description, and impact of the project.

  20. Energy Efficiency Challenges in Heating Supply System of Turkmenistan and Potential Solutions

    E-Print Network [OSTI]

    Zomov, A.; Behnke, R.

    2010-01-01

    to the population are simultaneously improved. Despite the energy, economic, and environmental benefits of energy efficiency in Turkmenistan, little has been done to eliminate energy waste. Due historic legacy, there is a limited institutional capacity to increase...

  1. Harnessing waste heat and reducing wasted lighting : three mechanical structures for efficient energy systems

    E-Print Network [OSTI]

    Stronger, Brad A

    2008-01-01

    This thesis presents three mechanical structures designed for efficient energy systems. In [3], Cooley presents a modification of a fluorescent lamp which allows it to detect nearby occupants and dim itself automatically. ...

  2. Modelling and Understanding of Highly Energy Efficient Fluids

    E-Print Network [OSTI]

    Thamali, R J K A; Liyanage, D D; Ukwatta, Ajith; Hewage, Jinasena; Witharana, Sanjeeva

    2016-01-01

    Conventional heat carrier liquids have demonstrated remarkable enhancement in heat and mass transfer when nanoparticles were suspended in them. These liquid-nanoparticle suspensions are now known as Nanofluids. However the relationship between nanoparticles and the degree of enhancement is still unclear, thus hindering the large scale manufacturing of them. Understanding of the energy and flow behaviour of nanofluids is therefore of wide interest in both academic and industrial context. In this paper we first model the heat transfer of a nanofluid in convection in a circular tube at macro-scale by using CFD code of OpenFoam. Then we zoon into nano-scale behaviour using the Molecular Dynamics (MD) simulation. In the latter we considered a system of water and Gold nanoparticles. A systematic increase of convective heat transfer was observed with increasing nanoparticle concentration. A maximum enhancement of 7.0% was achieved in comparison to base fluid water. This occurred when the gold volume fraction was 0.0...

  3. Device and method for relativistic electron beam heating of a high-density plasma to drive fast liners

    DOE Patents [OSTI]

    Thode, Lester E. (Los Alamos, NM)

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, hydrogen boron or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy and momentum into a small localized region of the high-density plasma target. Fast liners disposed in the high-density target plasma are explosively or ablatively driven to implosion by a heated annular plasma surrounding the fast liner which is generated by an annular relativistic electron beam. An azimuthal magnetic field produced by axial current flow in the annular plasma, causes the energy in the heated annular plasma to converge on the fast liner.

  4. Review of current status of high flux heat transfer techniques. Volume I. Text + Appendix A

    SciTech Connect (OSTI)

    Bauer, W.H.; Gordon, H.S.; Lackner, H.; Mettling, J.R.; Miller, J.E.

    1980-09-01

    The scope of this work comprised two tasks. The first was to review high heat flux technology with consideration given to heat transfer panel configuration, diagnostics techniques and coolant supply. The second task was to prepare a report describing the findings of the review, to recommend the technology offering the least uncertainty for scale-up for the MFTF-B requirement and to recommend any new or perceived requirements for R and D effort.

  5. Designing nanoparticles for highly efficient endothelial siRNA delivery

    E-Print Network [OSTI]

    Dahlman, James E

    2015-01-01

    RNA potently regulates gene expression. However, the utility of RNA has been limited by the ability to efficiently deliver it to specific cells in vivo. In vivo RNA delivery is challenging; vehicles must avoid phagocytosis ...

  6. Webinar January 13: Highly Efficient Solar Thermochemical Reaction...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    efficiency, converting methane and water into syngas-a mix of hydrogen and carbon monoxide-and the technology received an R&D 100 Award in 2014. As the solar energy is stored...

  7. High Efficiency Microturbine Leads to Increased Market Share...

    Office of Environmental Management (EM)

    power system that led to the commercialization of that product. Capstone increased electrical efficiency of the unit from about 17%-22% to 33%, and it has seen more than 83...

  8. High-Efficiency Rooftop Air Conditioners: Innovative Procurement...

    Office of Scientific and Technical Information (OSTI)

    air conditioner manufacturers to produce equipment that exceeded US energy efficiency standards by at least 25% at a lower life-cycle cost. An outgrowth of the project, a...

  9. High-Efficiency Engine Technologies Session Introduction | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    the 16th Directions in Engine-Efficiency and Emissions Research (DEER) Conference in Detroit, MI, September 27-30, 2010. deer10rotz.pdf More Documents & Publications Increased...

  10. Can High Frequency Acoustic Waves Heat the Quiet Sun Chromosphere?

    E-Print Network [OSTI]

    Mats Carlsson; Viggo H. Hansteen; Bart De Pontieu; Scott McIntosh; Theodore D. Tarbell; Dick Shine; Saku Tsuneta; Yukio Katsukawa; Kiyoshi Ichimoto; Yoshinori Suematsu; Toshifumi Shimizu; Shin'ichi Nagata

    2007-09-21

    We use Hinode/SOT Ca II H-line and blue continuum broadband observations to study the presence and power of high frequency acoustic waves at high spatial resolution. We find that there is no dominant power at small spatial scales; the integrated power using the full resolution of Hinode (0.05'' pixels, 0.16'' resolution) is larger than the power in the data degraded to 0.5'' pixels (TRACE pixel size) by only a factor of 1.2. At 20 mHz the ratio is 1.6. Combining this result with the estimates of the acoustic flux based on TRACE data of Fossum & Carlsson (2006), we conclude that the total energy flux in acoustic waves of frequency 5-40 mHz entering the internetwork chromosphere of the quiet Sun is less than 800 W m$^{-2}$, inadequate to balance the radiative losses in a static chromosphere by a factor of five.

  11. Voltage breakdown limits at a high material temperature for rapid pulse heating in a vacuum

    SciTech Connect (OSTI)

    Pincosy, P A; Speer, R

    1999-06-07

    The proposed Advanced Hydro Facility (AHF) is required to produce multi-pulse radiographs. Electron beam pulse machines with sub-microsecond repetition are not yet available to test the problem of electron beam propagation through the hydro-dynamically expanding plasma from the nearby previously heated target material. A proposed test scenario includes an ohmically heated small volume of target material simulating the electron beam heating, along with an actual electron beam pulse impinging on nearby target material. A pulse power heating circuit was tested to evaluate the limits of pulse heating a small volume of material to tens of kilo-joules per gram. The main pulse heating time (50 to 100 ns) was to simulate the electron beam heating of a converter target material. To avoid skin heating non-uniformity a longer time scale pulse of a few microseconds first heats the target material to a few thousand degrees near the liquid to vapor transition. Under this state the maximum electric field that the current carrying conductor can support is the important parameter for insuring that the 100 ns heating pulse can deposit sufficient power. A small pulse power system was built for tests of this limit. Under cold conditions the vacuum electric field hold-off limit has been quoted as high as many tens of kilovolts per centimeter. The tests for these experiments found that the vacuum electric field hold-off was limited to a few kilovolts per centimeter when the material approached melting temperatures. Therefore the proposed test scenario for AHF was not achievable.*

  12. High Heat Flux Thermoelectric Module Using Standard Bulk Material |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious Rank EERE:FinancingPetroleum12,ExecutiveFinancing ProgramsDepartment of¡ ¢HelpHighJian Li,1 DOEFuel

  13. System Effects of High Efficiency Filters in Iain S. Walker , Darryl J. Dickerhoff, David Faulkner

    E-Print Network [OSTI]

    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 cases, increased blower.2) up to MERV 16. Measurements were recorded every ten seconds for blower power, filter pressure drop

  14. Integrated high efficiency blower apparatus for HVAC systems

    DOE Patents [OSTI]

    Liu, Xiaoyue; Weigman, Herman; Wang, Shixiao

    2007-07-24

    An integrated centrifugal blower wheel for a heating, ventilation and air conditioning (HVAC) blower unit includes a first blade support, a second blade support, and a plurality of S-shaped blades disposed between the first and second blade supports, wherein each of the S-shaped blades has a trailing edge bent in a forward direction with respect to a defined direction of rotation of the wheel.

  15. Multi-scale framework for the accelerated design of high-efficiency...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Multi-scale framework for the accelerated design of high-efficiency organic photovoltaic cells Organic and hybrid organicinorganic solar cells (OSC) offer a promising low-cost...

  16. DOE Zero Energy Ready Home Low Load High Efficiency HVAC Webinar (Text Version)

    Broader source: Energy.gov [DOE]

    Below is the text version of the DOE Zero Energy Ready Home webinar, Low Load High Efficiency HVAC, presented in May 2014.

  17. Directed Evolution of a Highly Efficient Cellobiose Utilizing Pathway in an Industrial Saccharomyces

    E-Print Network [OSTI]

    Zhao, Huimin

    Directed Evolution of a Highly Efficient Cellobiose Utilizing Pathway in an Industrial, this strategy was applied to optimize a cellobiose utilizing pathway in an industrial Saccharomyces cerevisiae

  18. NASA's Marshall Space Flight Center Saves Water with High-Efficiency...

    Office of Environmental Management (EM)

    with High-Efficiency Toilet and Urinal Program NASA Marshall Space Flight Center Improves Cooling System Performance NASA's Marshall Space Flight Center Saves Water with...

  19. Simulation of High Efficiency Clean Combustion Engines and Detailed Chemical Kinetic Mechanisms Development

    Office of Energy Efficiency and Renewable Energy (EERE)

    Discusses ongoing work exploring fuel chemistry, analysis of and improving simulation methodologies for high efficiency clean combustion regimes, and computational performance

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

    SciTech Connect (OSTI)

    Not Available

    2011-05-01

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