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1

Three-junction solar cell  

SciTech Connect

A photovoltaic solar cell is formed in a monolithic semiconductor. The cell contains three junctions. In sequence from the light-entering face, the junctions have a high, a medium, and a low energy gap. The lower junctions are connected in series by one or more metallic members connecting the top of the lower junction through apertures to the bottom of the middle junction. The upper junction is connected in voltage opposition to the lower and middle junctions by second metallic electrodes deposited in holes 60 through the upper junction. The second electrodes are connected to an external terminal.

Ludowise, Michael J. (Cupertino, CA)

1986-01-01T23:59:59.000Z

2

Concentrator silicon cell research  

Science Conference Proceedings (OSTI)

This project continued the developments of high-efficiency silicon concentrator solar cells with the goal of achieving a cell efficiency in the 26 to 27 percent range at a concentration level of 150 suns of greater. The target efficiency was achieved with the new PERL (passivated emitter, rear locally diffused) cell structure, but only at low concentration levels around 20 suns. The PERL structure combines oxide passivation of both top and rear surfaces of the cells with small area contact to heavily doped regions on the top and rear surfaces. Efficiency in the 22 to 23 percent range was also demonstrated for large-area concentrator cells fabricated with the buried contact solar cell processing sequence, either when combined with prismatic covers or with other innovative approaches to reduce top contact shadowing. 19 refs.

Green, M.A.; Wenham, S.R.; Zhang, F.; Zhao, J.; Wang, A. [New South Wales Univ., Kensington (Australia). Solar Photovoltaic Lab.

1992-04-01T23:59:59.000Z

3

Photovoltaic concentrator initiative: Concentrator cell development  

DOE Green Energy (OSTI)

This project involves the development of a large-area, low-cost, high-efficiency concentrator solar cell for use in the Entech 22-sun linear-focus Fresnel lens concentrator system. The buried contact solar cell developed at the University of New South Wales was selected for this project. Both Entech and the University of New South Wales are subcontractors. This annual report presents the program efforts from November 1990 through December 1991, including the design of the cell, development of a baseline cell process, and presentation of the results of preliminary cell processing. Important results include a cell designed for operation in a real concentrator system and substitution of mechanical grooving for the previously utilized laser scribing.

Wohlgemuth, J.H.; Narayanan, S. [Solarex Corp., Frederick, MD (US)

1993-05-01T23:59:59.000Z

4

Manufacturing of ultra-high efficiency thin-film concentrator cells  

DOE Green Energy (OSTI)

This report describes a research project to study developments required to expedite commercializing the GaAs solar cell concentrator technology. We baseline the GaAs concentrator cell and 1000X module design into pilot operation at Kopin Corporation. To attain these improvements, we will use Kopin's existing pilot line to produce cleavage of lateral epitaxial film for transfer (CLEFT) GaAs solar cells; these cells already exhibit efficiencies of about 24% at air mass 1.5. We will modify the CLEFT cell to form concentrators that perform well at 500--1000 suns. We will derive the know-how for this modification from an integration of Kopin and VS Corporation technologies. The pilot line will be broadened to include cell receiver and module assembly, using VS Corporation technology obtained from Varian as a baseline. A second-generation design will be formulated to address improvements in the module, and these will be incorporated into the pilot line along with the CLEFT concentrator cell. In parallel, we integrate Kopin's CLEFT GaAs cell technology with the advanced AlGaAs and InGaAs material technology obtained by VS Corporation from Varian to develop a near-term, two-junction mechanical stack with an efficiency of 35%. The receiver thus developed will be compatible with a three-junction approach that has been proposed elsewhere by Kopin. Using a three-junction stack can yield an efficiency of over 40%, and when such cells become available, the pilot line process will have been designed to use them. 11 refs.

Gale, R. (Kopin Corp., Taunton, MA (United States))

1992-02-01T23:59:59.000Z

5

Silicon concentrator solar cell research  

DOE Green Energy (OSTI)

This report describes work conducted between December 1990 and May 1992 continuing research on silicon concentrator solar cells. The objectives of the work were to improve the performance of high-efficiency cells upon p-type substrates, to investigate the ultraviolet stability of such cells, to develop concentrator cells based on n-type substrates, and to transfer technology to appropriate commercial environments. Key results include the identification of contact resistance between boron-defused areas and rear aluminum as the source of anomalously large series resistance in both p- and n-type cells. A major achievement of the present project was the successful transfer of cell technology to both Applied Solar Energy Corporation and Solarex Corporation.

Green, M.A.; Zhao, J.; Wang, A.; Dai, X.; Milne, A.; Cai, S.; Aberle, A.; Wenham, S.R. [Univ. of New South Wales, Kensington, NSW (AU). Centre for Photovoltaic Devices and Systems

1993-06-01T23:59:59.000Z

6

Advanced high efficiency concentrator cells  

DOE Green Energy (OSTI)

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

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

1992-06-01T23:59:59.000Z

7

Development of concentrator solar cells  

DOE Green Energy (OSTI)

A limited pilot production run on PESC silicon solar cells for use at high concentrations (200 to 400 suns) is summarized. The front contact design of the cells was modified for operation without prismatic covers. The original objective of the contract was to systematically complete a process consolidation phase, in which all the, process improvements developed during the contract would be combined in a pilot production run. This pilot run was going to provide, a basis for estimating cell costs when produced at high throughput. Because of DOE funding limitations, the Photovoltaic Concentrator Initiative is on hold, and Applied Solar`s contract was operated at a low level of effort for most of 1993. The results obtained from the reduced scope pilot run showed the effects of discontinuous process optimization and characterization. However, the run provided valuable insight into the technical areas that can be optimized to achieve the original goals of the contract.

Not Available

1994-08-01T23:59:59.000Z

8

Gas concentration cells for utilizing energy  

DOE Patents (OSTI)

An apparatus and method for utilizing energy, in which the apparatus may be used for generating electricity or as a heat pump. When used as an electrical generator, two gas concentration cells are connected in a closed gas circuit. The first gas concentration cell is heated and generates electricity. The second gas concentration cell repressurizes the gas which travels between the cells. The electrical energy which is generated by the first cell drives the second cell as well as an electrical load. When used as a heat pump, two gas concentration cells are connected in a closed gas circuit. The first cell is supplied with electrical energy from a direct current source and releases heat. The second cell absorbs heat. The apparatus has no moving parts and thus approximates a heat engine.

Salomon, Robert E. (Philadelphia, PA)

1987-01-01T23:59:59.000Z

9

Gas concentration cells for utilizing energy  

DOE Patents (OSTI)

An apparatus and method are disclosed for utilizing energy, in which the apparatus may be used for generating electricity or as a heat pump. When used as an electrical generator, two gas concentration cells are connected in a closed gas circuit. The first gas concentration cell is heated and generates electricity. The second gas concentration cell repressurizes the gas which travels between the cells. The electrical energy which is generated by the first cell drives the second cell as well as an electrical load. When used as a heat pump, two gas concentration cells are connected in a closed gas circuit. The first cell is supplied with electrical energy from a direct current source and releases heat. The second cell absorbs heat. The apparatus has no moving parts and thus approximates a heat engine. 4 figs.

Salomon, R.E.

1987-06-30T23:59:59.000Z

10

Si concentrator solar cell development. [Final report  

DOE Green Energy (OSTI)

This is the final report of a program to develop a commercial, high-efficiency, low-cost concentrator solar cell compatible with Spectrolab`s existing manufacturing infrastructure for space solar cells. The period covered is between 1991 and 1993. The program was funded through Sandia National Laboratories through the DOE concentrator initiative and, was also cost shared by Spectrolab. As a result of this program, Spectrolab implemented solar cells achieving an efficiency of over 19% at 200 to 300X concentration. The cells are compatible with DOE guidelines for a cell price necessary to achieve a cost of electricity of 12 cents a kilowatthour.

Krut, D.D. [Spectrolab, Inc., Sylmar, CA (United States)

1994-10-01T23:59:59.000Z

11

High-efficiency silicon concentrator cell commercialization  

SciTech Connect

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

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

1993-05-01T23:59:59.000Z

12

Immersion Cooling of Photovoltaic Cells in Highly Concentrated Solar Beams.  

E-Print Network (OSTI)

??Concentrated solar radiation can be utilized to generate electrical power from photovoltaic cells, but concentrated solar radiation increases the photovoltaic cell’s temperature. This increase in… (more)

Darwish, Ahmed

2011-01-01T23:59:59.000Z

13

High-efficiency concentrator silicon solar cells  

DOE Green Energy (OSTI)

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

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

1990-11-01T23:59:59.000Z

14

Thermal regeneration of an electrochemical concentration cell  

DOE Patents (OSTI)

A system and method are described for thermally regenerating an electrochemical concentration cell having first and second aluminum electrodes respectively positioned in contact with first and second electrolytes separated by an ion exchange member, the first and second electrolytes being composed of different concentrations of an ionic solvent and a salt, preferably an aluminum halide. The ionic solvent may be either organic or inorganic with a relatively low melting point, the ionic solvent and the salt form a complex wherein the free energy of formation of said complex is less than about -5 kcal/mole. A distillation column using solar heat or low grade industrial waste heat receives the first and second electrolytes and thermally decomposes the salt-solvent complex to provide feed material for the two half cells.

Krumpelt, M.; Bates, J.K.

1980-05-09T23:59:59.000Z

15

TOPCAT Solar Cell Alignment & Energy Concentration Technology ...  

Patent 7,667,833: Alignment method for parabolic trough solar concentrators A Theoretical Overlay Photographic (TOP) alignment method uses the overlay of a ...

16

New GaInP/GaAs/GaInAs, Triple-Bandgap, Tandem Solar Cell for High-Efficiency Terrestrial Concentrator Systems  

DOE Green Energy (OSTI)

GaInP/GaAs/GaInAs three-junction cells are grown in an inverted configuration on GaAs, allowing high quality growth of the lattice matched GaInP and GaAs layers before a grade is used for the 1-eV GaInAs layer. Using this approach an efficiency of 37.9% was demonstrated.

Kurtz, S.; Wanlass, M.; Kramer, C.; Young, M.; Geisz, J.; Ward, S.; Duda, A.; Moriarty, T.; Carapella, J.; Ahrenkiel, P.; Emery. K.; Jones, K.; Romero, M.; Kibbler, A.; Olson, J.; Friedman, D.; McMahon, W.; Ptak, A.

2005-11-01T23:59:59.000Z

17

Analysis of the GaInP/GaAs/1-eV/Ge Cell and Related Structures for Terrestrial Concentrator Application: Preprint  

DOE Green Energy (OSTI)

This conference paper describes the analysis of the potential of GaInP/GaAs/1-eV/Ge four-junction solar cell to improve on the efficiency of the state-of-the-art GaInP/GaAs/Ge benchmark. We emphasize three factors: (1) The newly proposed terrestrial concentrator spectrum has a lower ratio of red to blue light than does the old AM1.5 direct standard spectrum. (2) Standard two-layer antireflection coatings do not provide near-zero reflectance over the full spectral range of interest for these devices. (3) GaInNAs junctions used to date for the 1-eV junction have quantum efficiencies less than {approx}75%. These factors all limit the device current, adversely affecting the four-junction efficiency. We discuss strategies for ameliorating this problem, including going to alternate structures such as a GaInP/GaAs/0.9-eV three-junction device.

Friedman, D. J.; Kurtz, S. R.; Geisz, J. F.

2002-05-01T23:59:59.000Z

18

Segmented dish concentrator design project. [For solar cells  

SciTech Connect

The module uses a non-imaging thermoformed reflector consisting of tiers of conical reflecting surfaces sealed to a curved window which seals the mirror surfaces and the solar cells from the environment. A reflective coating is applied after the module is formed to the inside of the curved surfaces. Coatings of aluminum, silver, and copper were used. The receiver is a hexagonal prism machined on the surface of a metal pipe with the hexagonal shape around the circumference. The receiver holds 18, 2x2 cm. 40X solar cells. Three cells are mounted on each face of the six faces and can be wired in series or series-parallel. The cells are individually soldered to molybdenum with a tab for the back electrical connection. The molybdenum-solar cell combination is mounted to the heat sink with silicon rubber impregnated with powdered silicon. This provides an electrically insulating medium with reasonable thermally conductive properties. The hexagonal heat sink is inserted into the module from the rear, extending far enough into the module to intercept the light reflected from the conical tiers. Each tier illuminates the entire cell surface with the 5 tiers adding together to yield 40X concentration. Water flows inside the heat sink to dissipate the heat generated by the module. Electrical leads, water lines, and thermocouple wires are fed through the back and sealed to prevent environmental interference with the inner surfaces of the module. The module was tested at The University of Arizona. For the silver coated module, an overall efficiency of 7.6% was obtained with an input of 346 watts. Solar cell surface temperature was 50/sup 0/C. The cells were wired in series-parallel and a V/sub oc/ = 4 volts and an I/sub sc/ = 9.2 A was obtained. Four modules were delivered to Sandia in March 1979.

Call, R.L.

1979-07-01T23:59:59.000Z

19

Electrorefining cell with parallel electrode/concentric cylinder cathode  

DOE Patents (OSTI)

A cathode-anode arrangement for use in an electrolytic cell is adapted for electrochemically refining spent nuclear fuel from a nuclear reactor and recovering purified uranium and a mixture of uranium and plutonium for use as a fresh blanket and core fuel in a nuclear reactor. The arrangement includes a plurality of inner anodic dissolution baskets that are each attached to a respective support rod, are submerged in a molten lithium halide salt, and are rotationally displaced. An inner hollow cylindrical-shaped cathode is concentrically disposed about the inner anodic dissolution baskets. Concentrically disposed about the inner cathode in a spaced manner are a plurality of outer anodic dissolution baskets, while an outer hollow cylindrical-shaped cathode is disposed about the outer anodic dissolution baskets. Uranium is deposited from the anode baskets in a uniform cylindrical shape on the inner and outer cathode cylinders by rotating the anode baskets within the molten lithium halide salt. Scrapers located on each anode basket abrade and remove the spent fuel deposits on the surfaces of the inner and outer cathode cylinders, with the spent fuel falling to the bottom of the cell for removal. Cell resistance is reduced and uranium collection efficiency enhanced by increasing the electrode area and reducing the anode-cathode spacing for enhanced trapping and recovery of uranium dendrites scraped off of the cylindrical cathodes which may be greater in number than two.

Gay, E.C.; Miller, W.E.; Laidler, J.J.

1995-12-31T23:59:59.000Z

20

Bandgap Engineering in High-Efficiency Multijunction Concentrator Cells  

DOE Green Energy (OSTI)

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

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

2005-08-01T23:59:59.000Z

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


21

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

E-Print Network (OSTI)

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

Chow, Simon Ka Ming

2011-01-01T23:59:59.000Z

22

Flexible thermal cycle test equipment for concentrator solar cells  

SciTech Connect

A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

Hebert, Peter H. (Glendale, CA); Brandt, Randolph J. (Palmdale, CA)

2012-06-19T23:59:59.000Z

23

High-Efficiency, Self-Concentrating Nanoscale Solar Cell  

While solar cells have the potential to provide clean energy for a large portion of the earth's population, no one technology has provided the right ...

24

Cu(In,Ga)Se2 Thin-Film Concentrator Solar Cells: Preprint  

DOE Green Energy (OSTI)

Presented at the 2001 NCPV Program Review Meeting: CIGS cells were designed for operation under concentrated sunlight. This is first report of polycrystalline thin-film cell with efficiency>20%.

Ward, J.; Ramanathan, K.; Hasoon, F.; Coutts, T.; Keane, J.; Moriarty, T; Noufi, R.

2001-10-01T23:59:59.000Z

25

Accelerated aging of GaAs concentrator solar cells  

DOE Green Energy (OSTI)

An accelerated aging study of AlGaAs/GaAs solar cells has been completed. The purpose of the study was to identify the possible degradation mechanisms of AlGaAs/GaAs solar cells in terrestrial applications. Thermal storage tests and accelerated AlGaAs corrosion studies were performed to provide an experimental basis for a statistical analysis of the estimated lifetime. Results of this study suggest that a properly designed and fabricated AlGaAs/GaAs solar cell can be mechanically rugged and environmentally stable with projected lifetimes exceeding 100 years.

Gregory, P.E.

1982-04-01T23:59:59.000Z

26

Microfluidic concentration-enhanced single cell enzyme activity assay  

E-Print Network (OSTI)

Cells sense stimuli, process information and respond using signaling networks regulated by enzymatic activity of various proteins. Aberrations in signaling are associated with diseases such as cancer. Most current methods ...

Sarkar, Aniruddh

2013-01-01T23:59:59.000Z

27

Evaluation of concentration solar cells for terrestrial applications  

E-Print Network (OSTI)

Solar energy has become a hot prospect for the future replacement of fossil fuels, which have limited reserves and cause environmental problems. Solar cell is such a device to directly generate electricity from this clean ...

An, Tao, M. Eng. Massachusetts Institute of Technology

2008-01-01T23:59:59.000Z

28

High-Efficiency, Self-Concentrating Nanoscale Solar Cell - Energy ...  

While solar cells have the potential to provide clean energy for a large portion of the earth’s population, no one technology has provided the right combination of ...

29

The effects of concentrated ultraviolet light on high-efficiency silicon solar cells  

DOE Green Energy (OSTI)

The importance of stability in the performance of solar cells is clearly recognized as fundamental. Some of the highest efficiency silicon solar cells demonstrated to date, such as the Point Contact solar cell and the Passivated Emitter solar cell, rely upon the passivation of cell surfaces in order to minimize recombination, which reduces cell power output. Recently, it has been shown that exposure to ultraviolet (UV) light of wavelengths present in the terrestrial solar spectrum can damage a passivating silicon-oxide interface and increase recombination. In this study, we compared the performance of Point Contact and Passivated Emitter solar cells after exposure to UV light. We also examined the effect of UV exposure on oxide-passivated silicon wafers. We found that current Passivated Emitter designs are stable at both one-sun and under concentrated sunlight. The evolution of Point Contact concentrator cell performance shows a clear trend towards more stable cells. 15 refs., 18 figs.

Ruby, D.S.; Schubert, W.K.

1991-01-01T23:59:59.000Z

30

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

DOE Green Energy (OSTI)

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

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

1996-10-01T23:59:59.000Z

31

Single-junction solar cells with the optimum band gap for terrestrial concentrator applications  

DOE Patents (OSTI)

A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of "pinning" the optimum band gap for a wide range of operating conditions at a value of 1.14.+-.0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap.

Wanlass, Mark W. (Golden, CO)

1994-01-01T23:59:59.000Z

32

EC PVSEC, Glasgow, May 2000 EFFICIENT 20-50 SUN CONCENTRATOR CELLS  

E-Print Network (OSTI)

: The Australian National University, together with commercial partners, has developed a Photovoltaic / Trough concentration system. It comprises two-axis sun-tracking parabolic glass mirrors and a receiver with solar cells with conventional PV systems. The Australian National University has developed a Photovoltaic / Trough Concentration

33

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

DOE Green Energy (OSTI)

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

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

2000-01-01T23:59:59.000Z

34

What is the Appropriate Reference Condition for Optimizing Concentrator Cells? Preprint  

DOE Green Energy (OSTI)

This conference paper describes Consensus standards for determining the efficiency of a concentrator cell or module that have not been developed. NREL, Sandia National Laboratory, the Fraunhofer Institute for Solar Energy in Germany, and the Progress in Photovoltaics Efficiency Table authors have informally agreed upon concentrator-cell reference conditions. These conditions are 25C cell temperature, 1-sun=1000 W/m2 total irradiance, and the ASTM E891-87 direct-normal reference spectrum. Deficiencies in the direct reference spectrum are discussed, and a more representative reference spectrum for evaluating concentrator cells is proposed. The spectrum was generated by the SMARTS model, and the atmospheric parameters are as close as possible to the existing direct spectrum, with the exception that the aerosol optical depth at 500 nm is reduced from 0.27 to 0.085.

Emery, K.; Myers, D.; Kurtz, S.

2002-05-01T23:59:59.000Z

35

THE EFFECT OF LOW CONCENTRATIONS OF TETRACHLOROETHYLENE ON THE PERFORMANCE OF PEM FUEL CELLS  

Science Conference Proceedings (OSTI)

Polymer electrolyte membrane (PEM) fuel cells use components that are susceptible to contaminants in the fuel stream. To ensure fuel quality, standards are being set to regulate the amount of impurities allowable in fuel. The present study investigates the effect of chlorinated impurities on fuel cell systems using tetrachloroethylene (PCE) as a model compound for cleaning and degreasing agents. Concentrations between 0.05 parts per million (ppm) and 30 ppm were studied. We show how PCE causes rapid drop in cell performances for all concentrations including 0.05 ppm. At concentrations of 1 and 0.05 ppm, PCE poisoned the cell at a rate dependent on the dosage of the contaminant delivered to the cell. PCE appears to affect the cell when the cell potential was over potentials higher than approximately 0.2 V. No effects were observed at voltages around or below 0.2 V and the cells could be recovered from previous poisoning performed at higher potentials. Recoveries at those low voltages could be induced by changing the operating voltage or by purging the system. Poisoning did not appear to affect the membrane conductivity. Measurements with long-path length IR results suggested catalytic decomposition of the PCE by hydrogen over the anode catalyst.

COLON-MERCHADO, H.; MARTINEZ-RODRIGUEZ, M.; FOX, E.; RHODES, W.; MCWHORTER, C.; GREENWAY, S.

2011-04-18T23:59:59.000Z

36

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

DOE Green Energy (OSTI)

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

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

1992-06-01T23:59:59.000Z

37

Single-junction solar cells with the optimum band gap for terrestrial concentrator applications  

DOE Patents (OSTI)

A single-junction solar cell is described having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown that the presence of absorption bands in the direct spectrum has the effect of ''pinning'' the optimum band gap for a wide range of operating conditions at a value of 1.14[+-]0.02 eV. Efficiencies exceeding 30% may be possible at high concentration ratios for devices with the ideal band gap. 7 figures.

Wanlass, M.W.

1994-12-27T23:59:59.000Z

38

The performance of bifacial solar cells in prism-coupled compound parabolic concentrators  

SciTech Connect

Fixed compound parabolic concentrators that couple radiation to solar cells through a prism-shaped dielectric medium were matched to bifacial solar cell arrays. Measures of annual-average short-circuit current output relative to the output with conventional panel operation of the arrays gave optical gains of approximately four times with symmetrical but simulated bifacial arrays and approximately three times with the asymmetrical Westinghouse bifacial arrays. When passive thermosyphon cooling was provided, the power gains measured at peak solar intensity were similar to the optical gains.

Edmonds, I.R. (Queensland Univ. of Technology, Brisbane (Australia))

1992-01-01T23:59:59.000Z

39

Method of monitoring CO concentrations in hydrogen feed to a PEM fuel cell  

DOE Green Energy (OSTI)

The CO concentration in the H.sub.2 feed stream to a PEM fuel cell stack is monitored by measuring current and/or voltage behavior patterns from a PEM-probe communicating with the reformate feed stream. Pattern recognition software may be used to compare the current and voltage patterns from the PEM-probe to current and voltage telltale outputs determined from a reference cell similar to the PEM-probe and operated under controlled conditions over a wide range of CO concentrations in the H.sub.2 fuel stream. The PEM-probe is intermittently purged of any CO build-up on the anode catalyst (e.g., by (1) flushing the anode with air, (2) short circuiting the PEM-probe, or (3) reverse biasing the PEM-probe) to keep the PEM-probe at peak performance levels.

Grot, Stephen Andreas (Rochester, NY); Meltser, Mark Alexander (Pittsford, NY); Gutowski, Stanley (Pittsford, NY); Neutzler, Jay Kevin (Rochester, NY); Borup, Rodney Lynn (East Rochester, NY); Weisbrod, Kirk (Los Alamos, NM)

2000-01-01T23:59:59.000Z

40

Microfluidic system with integrated electroosmotic pumps, concentration gradient generator and fish cell line (RTgill-W1)--towards water toxicity  

E-Print Network (OSTI)

, and the results were quantified using a Live/DeadTM cell assay. This work is a preliminary study cell line (RTgill-W1)--towards water toxicity testing Tomasz Glawdel,a Caglar Elbuken,a Lucy E. J. Leeb that incorporates electroosmotic pumps, a concentration gradient generator and a fish cell line (rainbow trout gill

Le Roy, Robert J.

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


41

An Estimate of the Vertical Ozone Profile Discrepancy between the Australian Brewer–Mast and Electrochemical Concentration Cell Ozonesondes  

Science Conference Proceedings (OSTI)

An analysis is described that provides an additive correction for referencing the vertical ozone profiles of the Australian Brewer–Mast (BM; October 1984–December 1990) ozonesonde to those of the electrochemical concentration cell (ECC; January ...

Paul Lehmann

2005-12-01T23:59:59.000Z

42

Electrochemical concentration cell (ECC) ozonesonde pump efficiency measurements and tests on the sensitivity to ozone of buffered and  

E-Print Network (OSTI)

Electrochemical concentration cell (ECC) ozonesonde pump efficiency measurements and tests of new, direct measurements of the ozonesonde pump flow rate efficiency made in an environmental chamber using an oil bubble flowmeter developed at National Oceanic and Atmospheric Administration

Vömel, Holger

43

Cytokine-capture nanoparticles to quantify IL-2 concentrations within the immunological synapse during T cell activation  

E-Print Network (OSTI)

The feasibility of bringing a nascent technology for detection and quantification of local cytokine concentrations on cell surfaces to market is presented in this paper. Quantum dots or fluorochrome-loaded nanoparticles ...

Hong, Julee Y. (Julee Yang-A.), 1980-

2003-01-01T23:59:59.000Z

44

Standard Test Method for Calibration of Non-Concentrator Photovoltaic Secondary Reference Cells  

E-Print Network (OSTI)

1.1 This test method covers calibration and characterization of secondary terrestrial photovoltaic reference cells to a desired reference spectral irradiance distribution. The recommended physical requirements for these reference cells are described in Specification E1040. Reference cells are principally used in the determination of the electrical performance of a photovoltaic device. 1.2 Secondary reference cells are calibrated indoors using simulated sunlight or outdoors in natural sunlight by reference to a primary reference cell previously calibrated to the same desired reference spectral irradiance distribution. 1.3 Secondary reference cells calibrated according to this test method will have the same radiometric traceability as the of the primary reference cell used for the calibration. Therefore, if the primary reference cell is traceable to the World Radiometric Reference (WRR, see Test Method E816), the resulting secondary reference cell will also be traceable to the WRR. 1.4 This test method appli...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

45

Design Of A Hybrid Jet Impingement / Microchannel Cooling Device For Densely Packed PV Cells Under High Concentration  

Science Conference Proceedings (OSTI)

A hybrid jet impingement / microchannel cooling scheme was designed and applied to densely packed PV cells under high concentration. An experimental study allows validating the principles of the design and confirming its applicability to the cited system. In order to study the characteristics of the device in a wide range of conditions

Jérôme Barrau; Joan Rosell; Manel Ibańez

2010-01-01T23:59:59.000Z

46

Estimation of aluminium fluoride concentration in aluminium reduction cells through a soft sensors approach  

Science Conference Proceedings (OSTI)

This work exploits a model for Aluminium Fluoride Concentration Measurement in the Aluminium Smelting process. This process variable is usually measured every 50-100 hours since it requires long laboratory analysis. This variable has a strong influence ... Keywords: aluminium smelting process, bath chemistry, fluoride concentration, neural networks, soft sensors

Otacilio Fontes; Fábio M. Soares; Roberto Limăo

2012-08-01T23:59:59.000Z

47

Optimized III-V Multijunction Concentrator Solar Cells on Patterned Si and Ge Substrates: Final Technical Report, 15 September 2004--30 September 2006  

DOE Green Energy (OSTI)

Goal is to demo realistic path to III-V multijunction concentrator efficiencies > 40% by substrate-engineering combining compositional grading with patterned epitaxy for small-area cells for high concentration.

Ringel, S. A.

2008-11-01T23:59:59.000Z

48

GaInP/GaAs/GaInAs Monolithic Tandem Cells for High-Performance Solar Concentrators  

DOE Green Energy (OSTI)

We present a new approach for ultra-high-performance tandem solar cells that involves inverted epitaxial growth and ultra-thin device processing. The additional degree of freedom afforded by the inverted design allows the monolithic integration of high-, and medium-bandgap, lattice-matched (LM) subcell materials with lower-bandgap, lattice-mismatched (LMM) materials in a tandem structure through the use of transparent compositionally graded layers. The current work concerns an inverted, series-connected, triple-bandgap, GaInP (LM, 1.87 eV)/GaAs (LM, 1.42 eV)/GaInAs (LMM, {approx}1 eV) device structure grown on a GaAs substrate. Ultra-thin tandem devices are fabricated by mounting the epiwafers to pre-metallized Si wafer handles and selectively removing the parent GaAs substrate. The resulting handle-mounted, ultra-thin tandem cells have a number of important advantages, including improved performance and potential reclamation/reuse of the parent substrate for epitaxial growth. Additionally, realistic performance modeling calculations suggest that terrestrial concentrator efficiencies in the range of 40-45% are possible with this new tandem cell approach. A laboratory-scale (0.24 cm2), prototype GaInP/GaAs/GaInAs tandem cell with a terrestrial concentrator efficiency of 37.9% at a low concentration ratio (10.1 suns) is described, which surpasses the previous world efficiency record of 37.3%.

Wanlass, M. W.; Ahrenkiel, S. P.; Albin, D. S.; Carapella, J. J.; Duda, A.; Emery, K.; Geisz, J. F.; Jones, K.; Kurtz, S.; Moriarty, T.; Romero, M. J.

2005-08-01T23:59:59.000Z

49

Tarn Yates, Senior Thesis, Physics Department UCSC Summer 2003 Solar Cells in Concentrating Systems  

E-Print Network (OSTI)

.1109/JMEMS.2006.880246 have been developed for remote sensors typically based on ei- ther optical [6], [7 allowing power to be delivered by three on- board photovoltaic (PV) cells. The sensor itself is comprised environment is elec- trodeposited as driven by the PV cell array. The total mass de- 1057-7157/$20.00 © 2006

50

Terrestrial Concentrator PV Modules Based on GaInP/GaAs/Ge TJ Cells and Minilens Panels  

SciTech Connect

This paper is a description of research activity in the field of cost-effective modules realizing the concept of very high solar concentration with small-aperture area Fresnel lenses and multijunction III-V cells. Structural simplicity and 'all-glass' design are the guiding principles of the corresponding development. The advanced concentrator modules are made with silicone Fresnel lens panels (from 8 up to 144 lenses, each lens is 4 times 4 cm{sup 2} in aperture area) with composite structure. GaInP/GaAs/Ge triple-junction cells with average efficiencies of 31.1 and 34.7% at 1000 suns were used for the modules. Conversion efficiency as high as 26.3% has been measured indoors in a test module using a newly developed large-area solar simulator.

Rumyantsev, V. D.; Sadchikov, N. A.; Chalov, A. E.; Ionova, E. A.; Friedman, D. J.; Glenn, G.

2006-01-01T23:59:59.000Z

51

0.7-eV GaInAs Junction for a GaInP/GaAs/GaInAs(1-eV)/GaInAs(0.7-eV) Four-Junction Solar Cell: Preprint  

DOE Green Energy (OSTI)

We discuss recent developments in III-V multijunction solar cells, focusing on adding a fourth junction to the Ga0.5In0.5P/GaAs/Ga0.75In0.25As inverted three-junction cell. This cell, grown inverted on GaAs so that the lattice-mismatched Ga0.75In0.25As third junction is the last one grown, has demonstrated 38% efficiency, and 40% is likely in the near future. To achieve still further gains, a lower-bandgap GaxIn1-xAs fourth junction could be added to the three-junction structure for a four-junction cell whose efficiency could exceed 45% under concentration. Here, we present the initial development of the GaxIn1-xAs fourth junction. Junctions of various bandgaps ranging from 0.88 to 0.73 eV were grown, in order to study the effect of the different amounts of lattice mismatch. At a bandgap of 0.88 eV, junctions were obtained with very encouraging {approx}80% quantum efficiency, 57% fill factor, and 0.36 eV open-circuit voltage. The device performance degrades with decreasing bandgap (i.e., increasing lattice mismatch). We model the four-junction device efficiency vs. fourth junction bandgap to show that an 0.7-eV fourth-junction bandgap, while optimal if it could be achieved in practice, is not necessary; an 0.9-eV bandgap would still permit significant gains in multijunction cell efficiency while being easier to achieve than the lower-bandgap junction.

Friedman, D. J.; Geisz, J. F.; Norman, A. G.; Wanlass, M. W.; Kurtz, S. R.

2006-05-01T23:59:59.000Z

52

Concentrating Photovoltaics (Presentation)  

SciTech Connect

Solar is growing rapidly, and the concentrating photovoltaics industry-both high- and low-concentration cell approaches-may be ready to ramp production in 2009.

Kurtz, S.

2009-01-20T23:59:59.000Z

53

Manufacturing of High-Efficiency Bi-Facial Tandem Concentrator Solar Cells: February 20, 2009--August 20, 2010  

DOE Green Energy (OSTI)

Spire Semiconductor made concentrator photovoltaic (CPV) cells using a new bi-facial growth process and met both main program goals: a) 42.5% efficiency 500X (AM1.5D, 25C, 100mW/cm2); and b) Ready to supply at least 3MW/year of such cells at end of program. We explored a unique simple fabrication process to make a N/P 3-junction InGaP/GaAs/InGaAs tandem cells . First, the InGaAs bottom cell is grown on the back of a GaAs wafer. The wafers are then loaded into a cassette, spin-rinsed to remove particles, dipped in dilute NH4OH and spin-dried. The wafers are then removed from the cassette loaded the reactor for GaAs middle and InGaP top cell growth on the opposite wafer face (bi-facial growth). By making the epitaxial growth process a bit more complex, we are able to avoid more complex processing (such as large area wafer bonding or epitaxial liftoff) used in the inverted metamorphic (IMM) approach to make similar tandem stacks. We believe the yield is improved compared to an IMM process. After bi-facial epigrowth, standard III-V cell steps (back metal, photolithography for front grid, cap etch, AR coat, dice) are used in the remainder of the process.

Wojtczuk , S.

2011-06-01T23:59:59.000Z

54

Concentrator Photovoltaic Systems  

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

Concentrator photovoltaic (PV) systems use less solar cell material than other PV systems. PV cells are the most expensive components of a PV system, on a per-area basis. A concentrator makes use...

55

CPT1{alpha} over-expression increases long-chain fatty acid oxidation and reduces cell viability with incremental palmitic acid concentration in 293T cells  

Science Conference Proceedings (OSTI)

To test the cellular response to an increased fatty acid oxidation, we generated a vector for an inducible expression of the rate-limiting enzyme carnitine palmitoyl-transferase 1{alpha} (CPT1{alpha}). Human embryonic 293T kidney cells were transiently transfected and expression of the CPT1{alpha} transgene in the tet-on vector was activated with doxycycline. Fatty acid oxidation was measured by determining the conversion of supplemented, synthetic cis-10-heptadecenoic acid (C17:1n-7) to C15:ln-7. CPT1{alpha} over-expression increased mitochondrial long-chain fatty acid oxidation about 6-fold. Addition of palmitic acid (PA) decreased viability of CPT1{alpha} over-expressing cells in a concentration-dependent manner. Both, PA and CPT1{alpha} over-expression increased cell death. Interestingly, PA reduced total cell number only in cells over-expressing CPT1{alpha}, suggesting an effect on cell proliferation that requires PA translocation across the mitochondrial inner membrane. This inducible expression system should be well suited to study the roles of CPT1 and fatty acid oxidation in lipotoxicity and metabolism in vivo.

Jambor de Sousa, Ulrike L. [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland); Koss, Michael D. [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland); Fillies, Marion [Max Delbrueck Center for Molecular Medicine, Berlin (Germany); Gahl, Anja [Max Delbrueck Center for Molecular Medicine, Berlin (Germany); Scheeder, Martin R.L. [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland); Cardoso, M. Cristina [Max Delbrueck Center for Molecular Medicine, Berlin (Germany); Leonhardt, Heinrich [Max Delbrueck Center for Molecular Medicine, Berlin (Germany); Department of Biology II, Ludwig Maximilians University, Munich (Germany); Geary, Nori [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland); Langhans, Wolfgang [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland); Leonhardt, Monika [Institute of Animal Sciences, Swiss Federal Institute of Technology, Zurich (Switzerland)]. E-mail: monika.leonhardt@inw.agrl.ethz.ch

2005-12-16T23:59:59.000Z

56

Micropower chemical fuel-to-electric conversion : a "regenerative flip" hydrogen concentration cell promising near carnot efficiency.  

DOE Green Energy (OSTI)

Although battery technology is relatively mature, power sources continue to impose serious limitations for small, portable, mobile, or remote applications. A potentially attractive alternative to batteries is chemical fuel-to-electric conversion. Chemical fuels have volumetric energy densities 4 to 10 times those of batteries. However, realizing this advantage requires efficient chemical fuel-to-electric conversion. Direct electrochemical conversion would be the ideal, but, for most fuels, is generally not within the state-of-the-science. Next best, chemical-to-thermal-to-electric conversion can be attractive if efficiencies can be kept high. This small investigative project was an exploration into the feasibility of a novel hybrid (i.e., thermal-electrochemical) micropower converter of high theoretical performance whose demonstration was thought to be within near-term reach. The system is comprised of a hydrogen concentration electrochemical cell with physically identical hydrogen electrodes as anode and cathode, with each electrode connected to physically identical hydride beds each containing the same low-enthalpy-of-formation metal hydride. In operation, electrical power is generated by a hydrogen concentration differential across the electrochemical cell. This differential is established via coordinated heating and passive cooling of the corresponding hydride source and sink. Heating is provided by the exothermic combustion (i.e., either flame combustion or catalytic combustion) of a chemical fuel. Upon hydride source depletion, the role of source and sink are reversed, heating and cooling reversed, electrodes commutatively reversed, cell operation reversed, while power delivery continues unchanged. This 'regenerative flip' of source and sink hydride beds can be cycled continuously until all available heating fuel is consumed. Electricity is efficiently generated electrochemically, but hydrogen is not consumed, rather the hydrogen is regeneratively cycled as an electrochemical 'working fluid'.

Wally, Karl

2006-05-01T23:59:59.000Z

57

STATEMENT OF CONSIDERATIONS REQUEST BY EMCORE CORPORATION FOR...  

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

PATENT RIGHTS UNDER SUBCONTRACT NO. NREL-NAT-02-30620-03 ENTITLED "THREE-JUNCTION SOLAR CELL FOR HIGH CONCENTRATION APPLICATIONS" UNDER DOE PRIME CONTRACT NO. DE-FC36-83CH10093;...

58

Energy Basics: Concentrator Photovoltaic Systems  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

59

Standard Test Method for Calibration of Primary Non-Concentrator Terrestrial Photovoltaic Reference Cells Using a Tabular Spectrum  

E-Print Network (OSTI)

1.1 This test method is intended to be used for calibration and characterization of primary terrestrial photovoltaic reference cells to a desired reference spectral irradiance distribution, such as Tables G173. The recommended physical requirements for these reference cells are described in Specification E1040. Reference cells are principally used in the determination of the electrical performance of photovoltaic devices. 1.2 Primary photovoltaic reference cells are calibrated in natural sunlight using the relative spectral response of the cell, the relative spectral distribution of the sunlight, and a tabulated reference spectral irradiance distribution. 1.3 This test method requires the use of a pyrheliometer that is calibrated according to Test Method E816, which requires the use of a pyrheliometer that is traceable to the World Radiometric Reference (WRR). Therefore, reference cells calibrated according to this test method are traceable to the WRR. 1.4 This test method is a technique that may be used ...

American Society for Testing and Materials. Philadelphia

2010-01-01T23:59:59.000Z

60

Concentrator Photovoltaic Systems | Department of Energy  

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

Concentrator Photovoltaic Systems Concentrator Photovoltaic Systems August 20, 2013 - 4:12pm Addthis Concentrator photovoltaic (PV) systems use less solar cell material than other...

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


61

Photovoltaic solar concentrator  

SciTech Connect

A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

Nielson, Gregory N.; Okandan, Murat; Resnick, Paul J.; Cruz-Campa, Jose Luis

2012-12-11T23:59:59.000Z

62

An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell  

DOE Green Energy (OSTI)

This report describes work to develop inverted-grown Al[sub 0.34]Ga[sub 0.66]As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al[sub 0.34]Ga[sub 0.66]As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The cycled'' organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al[sub 0.34]Ga[sub 0.66]As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.

Venkatasubramanian, R. (Research Triangle Inst., Research Triangle Park, NC (United States))

1993-01-01T23:59:59.000Z

63

Concentrating Photovoltaics  

Science Conference Proceedings (OSTI)

Concentrating photovoltaics (CPV) are a promising alternative to flat-plate photovoltaics in high direct normal irradiance (DNI) environments. The technology’s basic operating characteristics offer significant upside compared with other solar technologies: higher system efficiencies of upwards of 30%+; higher capacity factors, generated through two-axis tracking, exceeding 30% in ideal locations; lower cellular degradation from heat compared to flat-plate PV; lower water requirements; and reduced footpri...

2010-11-19T23:59:59.000Z

64

Photovoltaic solar concentrator module  

DOE Patents (OSTI)

This invention consists of a planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation which includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor.

Chiang, C.J.

1991-05-16T23:59:59.000Z

65

Soret Effect Study on High-Pressure CO2-Water Solutions Using UV-Raman Spectroscopy and a Concentric-Tube Optical Cell  

Science Conference Proceedings (OSTI)

Spatially resolved deep-UV Raman spectroscopy was applied to solutions of CO2 and H2O (or D2O), which were subject to a temperature gradient in a thermally regulated high-pressure concentric-tube Raman cell in an attempt to measure a Soret effect in the vicinity of the critical point of CO2. Although Raman spectra of solutions of CO2 dissolved in D2O at 10 MPa and temperatures near the critical point of CO2 had adequate signal-to-noise and spatial resolution to observe a Soret effect with a Soret coefficient with magnitude of |ST| > 0.03, no evidence for an effect of this size was obtained for applied temperature gradients up to 19oC. The presence of 1 M NaCl did not make a difference. In contrast, the concentration of CO2 dissolved in H2O was shown to vary significantly across the temperature gradient when excess CO2 was present, but the results could be explained simply by the variation in CO2 solubility over the temperature range and not to kinetic factors. For mixtures of D2O dissolved in scCO2 at 10 MPa and temperatures close to the critical point of CO2, the Raman peaks for H2O were too weak to measure with confidence even at the limit of D2O solubility.

Windisch, Charles F.; McGrail, B. Peter; Maupin, Gary D.

2012-01-01T23:59:59.000Z

66

Concentrator Photovoltaic System Basics | Department of Energy  

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

Concentrator Photovoltaic System Basics Concentrator Photovoltaic System Basics Concentrator Photovoltaic System Basics August 20, 2013 - 4:12pm Addthis Concentrator photovoltaic (PV) systems use less solar cell material than other PV systems. PV cells are the most expensive components of a PV system, on a per-area basis. A concentrator makes use of relatively inexpensive materials such as plastic lenses and metal housings to capture the solar energy shining on a fairly large area and focus that energy onto a smaller area-the solar cell. One measure of the effectiveness of this approach is the concentration ratio-in other words, how much concentration the cell is receiving. Concentrator PV systems have several advantages over flat-plate systems. First, concentrator systems reduce the size or number of cells needed and

67

Photovoltaic concentrator module improvements study  

DOE Green Energy (OSTI)

This report presents results of a project to design and fabricate an improved photovoltaic concentrator module. Using previous work as a baseline, this study conducted analyses and testing to select major module components and design features. The lens parquet and concentrator solar cell were selected from the highest performing, available components. A single 185X point-focus module was fabricated by the project team and tested at Sandia. Major module characteristics include a 6 by 4 compression-molded acrylic lens parquet (0.737 m{sup 2} area), twenty-four 0.2 ohms-cm, FZ, p-Si solar cells (1.56 cm{sup 2} area) soldered to ceramic substrates and copper heat spreaders, and an aluminized steel housing with corrugated bottom. This project marked the first attempt to use prismatic covers on solar cells in a high-concentration, point-focus application. Cells with 15 percent metallization were obtained, but problems with the fabrication and placement of prismatic covers on these cells lead to the decision not to use covers in the prototype module. Cell assembly fabrication, module fabrication, and module optical design activities are presented here. Test results are also presented for bare cells, cell assemblies, and module. At operating conditions of 981 watts/m{sup 2} DNI and an estimated cell temperature of 65{degrees}C, the module demonstrated an efficiency of 13.9 percent prior to stressed environmental exposure. 12 refs., 56 figs., 7 tabs.

Levy, S.L.; Kerschen, K.A. (Black and Veatch, Kansas City, MO (United States)); Hutchison, G. (Solar Kinetics, Inc., Dallas, TX (United States)); Nowlan, M.J. (Spire Corp., Bedford, MA (United States))

1991-08-01T23:59:59.000Z

68

Characterization of Photovoltaic Concentrators  

DOE Green Energy (OSTI)

This paper will describe the resources at the National Renewable Energy Laboratory (NREL) for performing characterization of photovoltaic (PV) materials designed for operation under concentrated light. NREL has the capability to measure devices ranging from very small, unencapsulated research cells to reasonably sized, environmentally protected modules. Data gathering and interpretation are also ongoing areas of revision and improvement. The main goal of the current research is to reduce the measurement uncertainty to the lowest practical value. At present, the state of the art is limited at a ?5% level in measuring efficiency accurately.

Kiehl, J.; Emery, E.

2005-01-01T23:59:59.000Z

69

Universal solar concentrator panel  

SciTech Connect

This patent describes a solar concentrator device. It comprises: a solar energy receiver; and a flat solar energy reflector arranged to reflect solar energy to the receiver, the reflector including a substantially square-shaped frame limiting an inner space, individual flat reflective panels arranged in the space in a first group or rows extending in a first direction and a second group of rows extending in a second direction substantially transverse to the first direction and so that each of the panels is turnable about three mutually perpendicular axes, and means for mounting the panels so that they are turnable about the axes. The mounting means including first means which connect the panels in the rows extending in one of the directions so that the panels in each of the rows extending in the one direction are jointly turnable about a first one of the axes, second means for mounting each of the panels so that in each of the rows extending in the one direction each of the panels is turnable about a second one of the axes, and third means for mounting each panel in each of the rows extending in the one direction so that each of the panels is turnable about a third one of the axes. This patent also describes a solar concentrator device, wherein the receiver includes a box forming an inner chamber, a plurality of photovoltaic cells sealed with a clear plastic and accommodated in the chamber, and water filling the chamber and surrounding the photovoltaic cells.

Bagno, R.G.

1991-03-12T23:59:59.000Z

70

Tissue transglutaminase treatment leads to concentration-dependent changes in dendritic cell phenotype - implications for the role of transglutaminase in coeliac disease  

E-Print Network (OSTI)

2007, 357:1731-1743. 14. Jensen K, Sollid LM, Scott H, Paulsen G, Kett K, Thorsby E, Lundin KEA: Gliadin-specific T cell responses in peripheral blood of healthy individuals involve T cells restricted by the coeliac disease associated DQ2 heterodimer...

Dalleywater, William J; Chau, David YS; Ghaemmaghami, Amir M

2012-04-16T23:59:59.000Z

71

Energy Basics: Linear Concentrator Systems for Concentrating...  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Concentrating Solar Power Linear...

72

Concentrating Solar Power Forum Concentrating Photovoltaics (Presentation)  

DOE Green Energy (OSTI)

This presentation's summaries: a convenient truth, comparison of three concentrator technologies, value of high efficiency, and status of industry.

Kurtz, S.

2008-05-06T23:59:59.000Z

73

Planar photovoltaic solar concentrator module  

DOE Patents (OSTI)

A planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor. 5 figs.

Chiang, C.J.

1992-12-01T23:59:59.000Z

74

Planar photovoltaic solar concentrator module  

DOE Patents (OSTI)

A planar photovoltaic concentrator module for producing an electrical signal from incident solar radiation includes an electrically insulating housing having a front wall, an opposing back wall and a hollow interior. A solar cell having electrical terminals is positioned within the interior of the housing. A planar conductor is connected with a terminal of the solar cell of the same polarity. A lens forming the front wall of the housing is operable to direct solar radiation incident to the lens into the interior of the housing. A refractive optical element in contact with the solar cell and facing the lens receives the solar radiation directed into the interior of the housing by the lens and directs the solar radiation to the solar cell to cause the solar cell to generate an electrical signal. An electrically conductive planar member is positioned in the housing to rest on the housing back wall in supporting relation with the solar cell terminal of opposite polarity. The planar member is operable to dissipate heat radiated by the solar cell as the solar cell generates an electrical signal and further forms a solar cell conductor connected with the solar cell terminal to permit the electrical signal generated by the solar cell to be measured between the planar member and the conductor.

Chiang, Clement J. (New Brunswick, NJ)

1992-01-01T23:59:59.000Z

75

Concentrating Solar Power Forum Concentrating Photovoltaics (Presentation)  

SciTech Connect

This presentation's summaries: a convenient truth, comparison of three concentrator technologies, value of high efficiency, and status of industry.

Kurtz, S.

2008-05-06T23:59:59.000Z

76

An inverted AlGaAs/GaAs patterned-Ge tunnel junction cascade concentrator solar cell. Final subcontract report, 1 January 1991--31 August 1992  

DOE Green Energy (OSTI)

This report describes work to develop inverted-grown Al{sub 0.34}Ga{sub 0.66}As/GaAs cascades. Several significant developments are reported on as follows: (1) The AM1.5 1-sun total-area efficiency of the top Al{sub 0.34}Ga{sub 0.66}As cell for the cascade was improved from 11.3% to 13.2% (NREL measurement [total-area]). (2) The ``cycled`` organometallic vapor phase epitaxy growth (OMVPE) was studied in detail utilizing a combination of characterization techniques including Hall-data, photoluminescence, and secondary ion mass spectroscopy. (3) A technique called eutectic-metal-bonding (EMB) was developed by strain-free mounting of thin GaAs-AlGaAs films (based on lattice-matched growth on Ge substrates and selective plasma etching of Ge substrates) onto Si carrier substrates. Minority-carrier lifetime in an EMB GaAs double-heterostructure was measured as high as 103 nsec, the highest lifetime report for a freestanding GaAs thin film. (4) A thin-film, inverted-grown GaAs cell with a 1-sun AM1.5 active-area efficiency of 20.3% was obtained. This cell was eutectic-metal-bonded onto Si. (5) A thin-film inverted-grown, Al{sub 0.34}Ga{sub 0.66}As/GaAs cascade with AM1.5 efficiency of 19.9% and 21% at 1-sun and 7-suns, respectively, was obtained. This represents an important milestone in the development of an AlGaAs/GaAs cascade by OMVPE utilizing a tunnel interconnect and demonstrates a proof-of-concept for the inverted-growth approach.

Venkatasubramanian, R. [Research Triangle Inst., Research Triangle Park, NC (United States)

1993-01-01T23:59:59.000Z

77

Linear Concentrator Systems for Concentrating Solar Power  

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

Linear concentrating solar power (CSP) collectors capture the sun's energy with large mirrors that reflect and focus the sunlight onto a linear receiver tube. The receiver contains a fluid that is...

78

Heat Pipe Performance Enhancement with Binary Mixture Fluids that Exhibit Strong Concentration Marangoni Effects  

E-Print Network (OSTI)

100 suns) and high (>100 suns) solar concentration levels [system. For the same 30 suns solar concentration, the heatat a predicted solar concentration of 162 suns. Solar cell

Armijo, Kenneth Miguel

2011-01-01T23:59:59.000Z

79

Concentrating Solar Power  

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

Concentrating solar power (CSP) technologies use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat. This thermal energy can then be used to...

80

Concentrating Solar Power  

DOE Green Energy (OSTI)

Summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

Not Available

2008-09-01T23:59:59.000Z

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


81

Lithium Concentration and Diffusion  

Science Conference Proceedings (OSTI)

... a variety of mobile power applications (laptops, automobiles, cell phones) due ... Similar to water management in fuel cells, the in situ measurement of ...

2010-10-05T23:59:59.000Z

82

Photovoltaic concentrator technology development project. Sixth project integration meeting  

DOE Green Energy (OSTI)

Thirty-three abstracts and short papers are presented which describe the current status of research, development, and demonstration of concentrator solar cell technology. Solar concentrators discussed include the parabolic trough, linear focus Fresnel lens, point focus Fresnel lens, and the parabolic dish. Solar cells studied include silicon, GaAs, and AlGaAs. Research on multiple junction cells, combined photovoltaic/thermal collectors, back contact solar cells, and beam splitter modules is described. Concentrator solar cell demonstration programs are reported. Contractor status summaries are given for 33 US DOE concentrator solar cell contracts; a description of the project, project status, and key results to date is included. (WHK)

None

1980-10-01T23:59:59.000Z

83

Concentration with uniform flux  

SciTech Connect

A modification of a parabolic cylinder concentrator is developed to procedure uniform flux. The controlling surface equation is given. A three-dimensional ray-trace technique is used to obtain the shape of the image at the focal plane of a thin slice of the mirror. Also, the concentration distribution for uniform flux is given. 1 references, 7 figures.

Not Available

1986-01-01T23:59:59.000Z

84

Oxygen Concentration Microgradients for Cell Culture  

E-Print Network (OSTI)

Optical Properties of Indium Tin Oxide Thin Films,” J. Am.peroxidase ITO : Indium tin oxide LB : Luria-Betani MHC :gradient. Patterning Indium tin oxide (ITO) is widely used

Park, Jaehyun

2010-01-01T23:59:59.000Z

85

Organic photovoltaics and concentrators  

E-Print Network (OSTI)

The separation of light harvesting and charge generation offers several advantages in the design of organic photovoltaics and organic solar concentrators for the ultimate end goal of achieving a lower cost solar electric ...

Mapel, Jonathan King

2008-01-01T23:59:59.000Z

86

Concentrator-quality evaluation  

DOE Green Energy (OSTI)

The performance of a reflecting solar concentrator depends, of course, on its surface reflectance, but there are other important factors. Among these are sun-tracking errors, surface-slope errors, and surface irregularities. It is appropriate to use statistics to describe and analyze these non-deterministic factors. A scheme for specifying the quality of a solar concentrator that includes all these effects is described and illustrated. It is believed that this procedure is optimum in the sense that it requires a minimum of measurements to obtain a complete enough description of a concentrator to determine its optical performance under any operating geometry. The specification scheme is, therefore, suitable for use in general systems analysis studies involving solar concentrators.

Biggs, F.; Vittitoe, C.N.

1978-01-01T23:59:59.000Z

87

Joined concentric tubes  

SciTech Connect

Tubular objects having two or more concentric layers that have different properties are joined to one another during their manufacture primarily by compressive and friction forces generated by shrinkage during sintering and possibly mechanical interlocking. It is not necessary for the concentric tubes to display adhesive-, chemical- or sinter-bonding to each other in order to achieve a strong bond. This facilitates joining of dissimilar materials, such as ceramics and metals.

DeJonghe, Lutgard; Jacobson, Craig; Tucker, Michael; Visco, Steven

2013-01-01T23:59:59.000Z

88

Concentrating Photovoltaic Module Testing at NREL's Concentrating Solar Radiation Users Facility  

DOE Green Energy (OSTI)

There has been much recent interest in photovoltaic modules designed to operate with concentrated sunlight (>100 suns). Concentrating photovoltaic (CPV) technology offers an exciting new opportunity as a viable alternative to dish Stirling engines. Advantages of CPV include potential for>40% cell efficiency in the long term (25% now), no moving parts, no intervening heat transfer surface, near-ambient temperature operation, no thermal mass, fast response, concentration reduces cost of cells relative to optics, and scalable to a range of sizes. Over the last few years, we have conducted testing of several CPV modules for DOEs Concentrating Solar Power (CSP) program. The testing facilities are located at the Concentrating Solar Radiation Users Facility (CRULF) and consist the 10 kW High-Flux Solar Furnace (HFSF) and a 14m2 Concentrating Technologies, LLC (CTEK) dish. This paper will primarily describe the test capabilities; module test results will be detailed in the presentation.

Bingham, C.; Lewandowski, A.; Stone, K.; Sherif, R.; Ortabasi, U.; Kusek, S.

2003-05-01T23:59:59.000Z

89

ARM - Measurement - Aerosol concentration  

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

concentration concentration ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol concentration A measure of the amount of aerosol particles (e.g. number, mass, volume) per unit volume of air. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments AOS : Aerosol Observing System CSPHOT : Cimel Sunphotometer CPC : Condensation Particle Counter IAP : In-situ Aerosol Profiles (Cessna Aerosol Flights) TDMA : Tandem Differential Mobility Analyzer

90

A compound parabolic concentrator  

SciTech Connect

A compound parabolic concentrator (CPC) for solar energy applications is presented in this work. A prototype was built and its thermal performance was determined. Operating temperatures of the order of 150 /sup 0/C with a reasonable efficiency can be attained by means of a fixed CPC.

Manrique, J.A.

1984-05-01T23:59:59.000Z

91

Derived Concentration Technical Standard  

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

196-2011 196-2011 April 2011 DOE STANDARD DERIVED CONCENTRATION TECHNICAL STANDARD U.S. Department of Energy AREA ENVR Washington, D.C. 20585 Not Measurement Sensitive This document is available on the Department of Energy Technical Standards Program Web Site at http://www.hss.doe.gov/nuclearsafety/ns/techstds/standard/standard.html DOE-STD-1196-2011 ACKNOWLEDGEMENTS This Derived Concentration Technical Standard was a collaborative effort sponsored by the DOE Office of Environmental Policy and Assistance, with support from Department subject matter experts (SMEs) in the field of radiation protection. This standard, which complements DOE Order (O) 458.1, Radiation Protection of the Public and the Environment, was developed taking

92

Concentrating Solar Thermal Technology  

Science Conference Proceedings (OSTI)

After nearly 20 years of commercial dormancy, concentrating solar thermal (CST) power development and investment activity is heating up globally. Encouraged by volatile energy prices, carbon markets, and renewable-friendly policies, an increasing number of established companies, newcomers, utilities, and government agencies are planning to deploy CST systems to tap the technologies' improving conversion efficiencies and low-cost electricity production potential. This renewable energy technology perspecti...

2009-03-27T23:59:59.000Z

93

Optimizing luminescent solar concentrator design.  

DOE Green Energy (OSTI)

Luminescent Solar Concentrators (LSCs) use fluorescent materials and light guides to convert direct and diffuse sunlight into concentrated wavelength-shifted light that produces electrical power in small photovoltaic (PV) cells with the goal of significantly reducing the cost of solar energy utilization. In this paper we present an optimization analysis based on the implementation of a genetic algorithm (GA) subroutine to a numerical ray-tracing Monte Carlo model of an LSC, SIMSOLAR-P. The initial use of the GA implementation in SIMSOLAR-P is to find the optimal parameters of a hypothetical 'perfect luminescent material' that obeys the Kennard Stepanov (K-S) thermodynamic relationship between emission and absorption. The optimization balances the efficiency losses in the wavelength shift and PV conversion with the efficiency losses due to re-scattering of light out of the collector. The theoretical limits of efficiency are provided for one, two and three layer configurations; the results show that a single layer configuration is far from optimal and adding a second layer in the LSC with wavelength shifted material in the near infrared region significantly increases the power output, while the gain in power by adding a third layer is relatively small. The results of this study provide a theoretical upper limit to the performance of an LSC and give guidance for the properties required for luminescent materials, such as quantum nanocrystals, to operate efficiently in planar LSC configurations.

Hernandez-Noyola, H.; Potterveld, D. H.; Holt, R. J.; Darling, S. B. (Center for Nanoscale Materials); ( PHY)

2012-01-01T23:59:59.000Z

94

Optical modelling of square solar concentrator  

Science Conference Proceedings (OSTI)

This paper deals with the optical design of a photovoltaic solar concentrator composed by two squared reflection mirrors. The optical configuration of the device, is based on the Cassegrain telescope and designed in order to maximize the fill factor ... Keywords: photovoltaic, ray tracing, solar cell

Maurizio Carlini; Carlo Cattani; Andrea O. M. Tucci

2007-06-01T23:59:59.000Z

95

Nonimaging light concentrator with uniform irradiance  

DOE Patents (OSTI)

A nonimaging light concentrator system including a primary collector of light, an optical mixer disposed near the focal zone for collecting light from the primary collector, the optical mixer having a transparent entrance aperture, an internally reflective housing for substantially total internal reflection of light, a transparent exit aperture and an array of photovoltaic cells disposed near the transparent exit aperture.

Winston, Roland (Chicago, IL); Gee, Randy C. (Arvada, CO)

2003-04-01T23:59:59.000Z

96

METHOD OF ISOTOPE CONCENTRATION  

DOE Patents (OSTI)

A method of concentrating N/sup 15/ in a liquid is described. Gaseous nitric oxide and at least one liquid selected from the group consisting of the aqueous oxyacids and oxides of nitrogen, wherein the atomic ratio of oxygen to nitrogen is greater than unity, are brought into intimate contact to cause an enrichment of the liquid and a depletion of the gas in N/sup 15/. The liquid is, thereafter, reacted with sulfur dioxide to produce a gas contuining nitric oxide. The gas contuining nitric oxide is then continuously passed in countercurrent contact with the liquid to cause further enrichment of the liquid.

Taylor, T.I.; Spindel, W.

1960-02-01T23:59:59.000Z

97

Concentric Black Rings  

E-Print Network (OSTI)

We present new supersymmetric solutions of five-dimensional minimal supergravity that describe concentric black rings with an optional black hole at the common centre. Configurations of two black rings are found which have the same conserved charges as a single rotating black hole; these black rings can have a total horizon area less than, equal to, or greater than the black hole with the same charges. A numerical investigation of these particular black ring solutions suggests that they do not have closed timelike curves.

Jerome P. Gauntlett; Jan B. Gutowski

2004-08-02T23:59:59.000Z

98

Vapor concentration monitor  

DOE Patents (OSTI)

An apparatus for monitoring the concentration of a vapor, such as heavy water, having at least one narrow bandwidth in its absorption spectrum, in a sample gas such as air. The air is drawn into a chamber in which the vapor content is measured by means of its radiation absorption spectrum. High sensitivity is obtained by modulating the wavelength at a relatively high frequency without changing its optical path, while high stability against zero drift is obtained by the low frequency interchange of the sample gas to be monitored and of a reference sample. The variable HDO background due to natural humidity is automatically corrected.

Bayly, John G. (Deep River, CA); Booth, Ronald J. (Deep River, CA)

1977-01-01T23:59:59.000Z

99

Concentrating Solar Power (Fact Sheet)  

DOE Green Energy (OSTI)

Concentrating Solar Power (CSP) offers a utility-scale, firm, dispatchable renewable energy option that can help meet the nation's goal of making solar energy cost competitive with other energy sources by the end of the decade. The DOE SunShot Initiative is a collaborative national initiative to make solar energy technologies cost-competitive with other forms of energy by reducing the cost of solar energy systems by about 75% by the end of the decade. Reducing the total installed cost for utility-scale solar electricity to roughly 6 cents per kilowatt hour without subsidies will result in rapid, large-scale adoption of solar electricity across the United States. Reaching this goal will re-establish American technological leadership, improve the nation's energy security, and strengthen U.S. economic competitiveness in the global clean energy race. SunShot will work to bring down the full cost of solar - including the costs of solar cells and installation by focusing on four main pillars: (1) Technologies for solar cells and arrays that convert sunlight to energy; (2) Electronics that optimize the performance of the installation; (3) Improvements in the efficiency of solar manufacturing processes; and (4) Installation, design, and permitting for solar energy systems.

Not Available

2011-10-01T23:59:59.000Z

100

Optical oxygen concentration monitor  

DOE Patents (OSTI)

A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen's A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest.

Kebabian, Paul (Acton, MA)

1997-01-01T23:59:59.000Z

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


101

Optical oxygen concentration monitor  

DOE Patents (OSTI)

A system for measuring and monitoring the concentration of oxygen uses as a light source an argon discharge lamp, which inherently emits light with a spectral line that is close to one of oxygen`s A-band absorption lines. In a preferred embodiment, the argon line is split into sets of components of shorter and longer wavelengths by a magnetic field of approximately 2,000 Gauss that is parallel to the light propagation from the lamp. The longer wavelength components are centered on an absorption line of oxygen and thus readily absorbed, and the shorter wavelength components are moved away from that line and minimally absorbed. A polarization modulator alternately selects the set of the longer wavelength, or upshifted, components or the set of the shorter wavelength, or downshifted, components and passes the selected set to an environment of interest. After transmission over a path through that environment, the transmitted optical flux of the argon line varies as a result of the differential absorption. The system then determines the concentration of oxygen in the environment based on the changes in the transmitted optical flux between the two sets of components. In alternative embodiments modulation is achieved by selectively reversing the polarity of the magnetic field or by selectively supplying the magnetic field to either the emitting plasma of the lamp or the environment of interest. 4 figs.

Kebabian, P.

1997-07-22T23:59:59.000Z

102

Non-tracking solar concentrator with a high concentration ratio  

DOE Patents (OSTI)

A nontracking solar concentrator with a high concentration ratio is provided. The concentrator includes a plurality of energy absorbers which communicate with a main header by which absorbed heat is removed. Undesired heat flow of those absorbers not being heated by radiant energy at a particular instant is impeded, improving the efficiency of the concentrator.

Hinterberger, Henry (Batavia, IL)

1977-01-01T23:59:59.000Z

103

Energy Basics: Photovoltaic Cells  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

104

Optimized Designs and Materials for Nanostructure Based Solar Cells  

E-Print Network (OSTI)

for concentrator photovoltaic cells (CPV) is 100 K – 200 Kimplementing photovoltaic and photochemical cells on largeConcentrated Photovoltaic (CPV) cells have been demonstrated

Shao, Qinghui

2009-01-01T23:59:59.000Z

105

Performance, problems, and expectations of concentrator photovoltaic systems  

DOE Green Energy (OSTI)

The photovoltaic cell or solar cell can be used to convert sunlight directly into electrical energy and its relatively simple construction and absence of moving parts make these devices attractive for terrestrial power generation applications. The primary problem preventing large-scale application is the very high cost of solar cell arrays. For example, the most advanced solar cell is the silicon cell and, currently in the United States, silicon solar arrays cost about $15,000 per peak kilowatt in moderately large quantities. One approach to reducing the cost of solar cell arrays is to concentrate sunlight on the cells and increase the specific output power density of the cells. In this approach, expensive solar cell area is replaced by, hopefully, less expensive reflective or refractive concentrator materials. The United States Energy Research and Development Administration (ERDA) is supporting a program to develop concentrator photovoltaic systems with the primary objective to develop low-cost reliable systems for widespread terrestrial applications. The specific long-term cost goal for these systems is $500 per peak kilowatt by 1982. The most promising solar cell systems for concentrator applications are silicon and galium arsenide and these materials have received the most attention to date in the ERDA program. Design, preliminary performance testing results, and cost estimates for concentrator photovoltaic systems are discussed.

Burgess, E.L.

1977-01-01T23:59:59.000Z

106

Markets for concentrating solar power  

DOE Green Energy (OSTI)

The report describes the markets for concentrating solar power. As concentrating solar power technologies advance into the early stages of commercialization, their economic potential becomes more sharply defined and increasingly tangible.

Not Available

1998-04-01T23:59:59.000Z

107

Linear Concentrator System Basics for Concentrating Solar Power |  

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

Linear Concentrator System Basics for Concentrating Solar Power Linear Concentrator System Basics for Concentrating Solar Power Linear Concentrator System Basics for Concentrating Solar Power August 20, 2013 - 4:45pm Addthis Photo of numerous parallel rows of parabolic trough collectors tracking the sun. Cooling towers and other generator equipment are in the midst of the troughs, and two water tanks are in the background. The Solar Electric Generating Station IV power plant in California consists of many parallel rows of parabolic trough collectors that track the sun. The cooling towers can be seen with the water plume rising into the air, and white water tanks are in the background. Credit: Sandia National Laboratory / PIX 14955 Linear concentrating solar power (CSP) collectors capture the sun's energy with large mirrors that reflect and focus the sunlight onto a linear

108

NREL: Concentrating Solar Power Research - Southwest Concentrating Solar  

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

Southwest Concentrating Solar Power 1000-MW Initiative Southwest Concentrating Solar Power 1000-MW Initiative Photos of various concentrating solar power systems. NREL, working through SunLab, supports the U.S. Department of Energy's goal to install 1,000 megawatts (MW) of new concentrating solar power systems in the southwestern United States by 2010. This level of deployment, combined with research and development to reduce technology component costs, could help reduce concentrating solar power electricity costs to $0.07/kilowatt-hour. At this cost, concentrating solar power can compete effectively in the Southwest's energy markets. To achieve the Initiative's goal, the U.S. Department of Energy is partnering with the Western Governors' Association to encourage concentrating solar power installations in Arizona, California, Colorado,

109

Energy Basics: Concentrating Solar Power  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Concentrating Solar Power Linear...

110

Industrial solar breeder project using concentrator photovoltaics  

DOE Green Energy (OSTI)

The purpose of this program is to demonstrate the use of a concentrating photovoltaic system to provide the energy for operating a silicon solar cell production facility, i.e., to demonstrate a solar breeder. Solarex has proposed to conduct the first real test of the solar breeder concept by building and operating a 200 kW(e) (peak) concentrating photovoltaic system based on the prototype and system design developed during Phase I. This system will provide all of the electrical and thermal energy required to operate a solar cell production line. This demonstration would be conducted at the Solarex Rockville facility, with the photovoltaic array located over the company parking lot and on an otherwise unusable flood plain. Phase I of this program included a comprehensive analysis of the application, prototype fabrication and evaluation, system design and specification, and a detailed plan for Phases II and III. A number of prototype tracking concentrator solar collectors were constructed and operated. Extensive system analysis was performed to design the Phase II system as a stand-alone power supply for a solar cell production line. Finally, a detailed system fabrication proposal for Phase II and an operation and evaluation plan for Phase III were completed. These proposals included technical, management, and cost plans for the fabrication and exercise of the proposed system.

Hamilton, R.; Wohlgemuth, J.; Burkholder, J.; Levine, A.; Storti, G.; Wrigley, C.; McKegg, A.

1979-08-01T23:59:59.000Z

111

Multijunction Photovoltaic Technologies for High-Performance Concentrators: Preprint  

DOE Green Energy (OSTI)

Multijunction solar cells provide high-performance technology pathways leading to potentially low-cost electricity generated from concentrated sunlight. The National Center for Photovoltaics at the National Renewable Energy Laboratory has funded different III-V multijunction solar cell technologies and various solar concentration approaches. Within this group of projects, III-V solar cell efficiencies of 41% are close at hand and will likely be reported in these conference proceedings. Companies with well-developed solar concentrator structures foresee installed system costs of $3/watt--half of today's costs--within the next 2 to 5 years as these high-efficiency photovoltaic technologies are incorporated into their concentrator photovoltaic systems. These technology improvements are timely as new large-scale multi-megawatt markets, appropriate for high performance PV concentrators, open around the world.

McConnell, R.; Symko-Davies, M.

2006-05-01T23:59:59.000Z

112

NREL's PV Incubator: Where Solar Photovoltaic Records Go to be Broken |  

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

NREL's PV Incubator: Where Solar Photovoltaic Records Go to be NREL's PV Incubator: Where Solar Photovoltaic Records Go to be Broken NREL's PV Incubator: Where Solar Photovoltaic Records Go to be Broken June 28, 2011 - 11:44am Addthis NREL Principal Engineer Keith Emery prepares to load three-junction concentrator cells into NREL's
 High-Intensity Pulse Solar Simulator to test for efficiency. | Department of Energy Photo | Courtesy of National Renewable Energy Laboratory | Photo by Dennis Schroeder | Public Domain | NREL Principal Engineer Keith Emery prepares to load three-junction concentrator cells into NREL's
 High-Intensity Pulse Solar Simulator to test for efficiency. | Department of Energy Photo | Courtesy of National Renewable Energy Laboratory | Photo by Dennis Schroeder | Public Domain | Minh Le Minh Le

113

Planar micro-optic solar concentration  

E-Print Network (OSTI)

such as compound parabolic concentrators and nonimagingas kaleidoscopes or compound parabolic concentrators whicha variation of the compound parabolic concentrator, however,

Karp, Jason Harris

2010-01-01T23:59:59.000Z

114

NREL: Awards and Honors - Triple-Junction Terrestrial Concentrator Solar  

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

Triple-Junction Terrestrial Concentrator Solar Cell Triple-Junction Terrestrial Concentrator Solar Cell Developers: Dr. Jerry Olson, Dr. Sarah Kurtz, Dr. Daniel Friedman, Alan Kibbler, and Charlene Karmer, National Renewable Energy Laboratory; Dr. Richard King, Jim Ermer, Dmitri D. Krut, Hector Cotal, Peter Colter, Hojun Yoon, Nassar Karam, and Gregory S. Glenn, Spectrolab, Inc. The triple-junction solar cell - or TJ solar cell - generates a lot of energy from just a very little amount of material. How much energy? A 1-cm2 cell can generate as much as 35 W of power and produce as much as 86.3 kWh of electricity during a typical year under a Phoenix, AZ sun. This means that 100 to 150 of these cells could produce enough electricity to power the typical American household. This cell can do this, first, because it

115

Development of a commercial photovoltaic concentrator module  

DOE Green Energy (OSTI)

The ojective of this work was to develop the design and prototype of a commercial high-concentration photovoltaic (PV) module. The design is for a 282-sun point-focus concentrating module. Most of the components, subassemblies, and design features incorporate simplifications and ease of manufacturing. The Solar Kinetics, Inc. (SKI) module is designed to incorporate high-efficiency, single-crystal silicon PV cells. The housing is made with aluminum laminated for voltage stand-off and simultaneously providing high thermal conductivity. The Fresnel lens injection molded by American Optical (AO) as singles. The cell assembly consists of a copper heat spreader, a photovoltaic cell soldered, a top and bottom contact, and a reflective secondary optical element (SOE). The cell assemblies passed all of the initial electrical characterization and high-potential tests. Under environmental cycling, the only bond that failed was the PV cell-to-heat spreader interface. The other components (top contact, bottom contact, SOE) passed all the environmental cycling tests. The cell assemblies were designed to be mounted onto the receiver section with a thermally conductive RTV. This geometry was subjected to environmental testing. There was no delamination of this bond nor was there electrical breakdown when the assemblies were subjected to the hi-pot test. A mock module was fabricated for environmental evaluation. This module was subjected to the humidity/freeze cycling to assess the performance of the lens mounting design. This module was also subjected to the rain test after the humidity/freeze cycling and checked for water leaks. The lens showed small displacement from its original position after the environmental cycling. One tablespoon of water did collect inside the module.

Saifee, S.T.; Hutchison, G. [Solar Kinetics, Inc., Dallas, TX (United States)

1992-09-01T23:59:59.000Z

116

Cylindrical Acoustic Levitator/Concentrator  

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

Cylindrical Acoustic Levitator/Concentrator Cylindrical Acoustic Levitator/Concentrator Cylindrical Acoustic Levitator/Concentrator A low-power, inexpensive acoustic apparatus for levitation and/or concentration of aerosols and small liquid/solid samples having particulates up to several millimeters in diameter in air or other fluids is described. Available for thumbnail of Feynman Center (505) 665-9090 Email Cylindrical Acoustic Levitator/Concentrator A low-power, inexpensive acoustic apparatus for levitation and/or concentration of aerosols and small liquid/solid samples having particulates up to several millimeters in diameter in air or other fluids is described. It is constructed from a commercially available, hollow cylindrical piezoelectric crystal which has been modified to tune the resonance frequency of the breathing mode resonance of the crystal to that

117

ARM - Measurement - CO2 concentration  

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

: CO2 concentration The amount of carbon dioxide, a heavy, colorless greenhouse gas, per unit of volume. Categories Atmospheric Carbon Instruments The above measurement is...

118

Energy Basics: Concentrating Solar Power  

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

use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat. This thermal energy can then be used to produce electricity...

119

Cylindrical Acoustic Levitator/Concentrator  

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

A low-power, inexpensive acoustic apparatus for levitation andor concentration of aerosols and small liquidsolid samples having particulates up to several millimeters in...

120

Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Presentation)  

DOE Green Energy (OSTI)

Presented at the 7th International Conference on Concentrating Photovoltaic Systems (CPV-7), 4-6 April 2011, Las Vegas, Nevada. Many concentrating photovoltaic (CPV) systems use a polymeric encapsulant to couple an optical component and/or coverglass to the cell. In that location, the encapsulation improves the transmission of concentrated optical flux through interfaces(s) while protecting the cell from the environment. The durability of encapsulation materials, however, is not well established relative to the desired service life of 30 years. Therefore, we have initiated a screen test to identify the field-induced failure modes for a variety of popular PV encapsulation materials.

Miller, D. C.; Muller, M.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

2011-04-01T23:59:59.000Z

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


121

Limit of concentration under extended nonhomogeneous light sources  

SciTech Connect

Static photovoltaic concentrators, which see the sky as an extended distribution of radiance, are analyzed in a general way. The rules for achieving the highest energy on the cell are derived and the appropriate figures of merit are defined. It is concluded that casting increasingly high values of energy on the cell, which would be bifacial, require collecting a lower portion of the total sky energy. The corresponding figures of merit for the concentrators of the CPC family are analyzed, concluding that a better type of concentrator should be developed for photovoltaic applications.

Minano, J.C.; Luque, A.

1983-09-01T23:59:59.000Z

122

DOE High Performance Concentrator PV Project  

DOE Green Energy (OSTI)

Much in demand are next-generation photovoltaic (PV) technologies that can be used economically to make a large-scale impact on world electricity production. The U.S. Department of Energy (DOE) initiated the High-Performance Photovoltaic (HiPerf PV) Project to substantially increase the viability of PV for cost-competitive applications so that PV can contribute significantly to both our energy supply and environment. To accomplish such results, the National Center for Photovoltaics (NCPV) directs in-house and subcontracted research in high-performance polycrystalline thin-film and multijunction concentrator devices with the goal of enabling progress of high-efficiency technologies toward commercial-prototype products. We will describe the details of the subcontractor and in-house progress in exploring and accelerating pathways of III-V multijunction concentrator solar cells and systems toward their long-term goals. By 2020, we anticipate that this project will have demonstrated 33% system efficiency and a system price of $1.00/Wp for concentrator PV systems using III-V multijunction solar cells with efficiencies over 41%.

McConnell, R.; Symko-Davies, M.

2005-08-01T23:59:59.000Z

123

Device for measuring the total concentration of oxygen in gases  

DOE Patents (OSTI)

This invention provides a CO equilibrium in a device for measuring the total concentration of oxygen impurities in a fluid stream. To this end, the CO equilibrium is produced in an electrochemical measuring cell by the interaction of a carbon element in the cell with the chemically combined and uncombined oxygen in the fluid stream at an elevated temperature.

Isaacs, Hugh S. (Shoreham, NY); Romano, Anthony J. (Kings Park, NY)

1977-01-01T23:59:59.000Z

124

Process for concentrated biomass saccharification  

DOE Patents (OSTI)

Processes for saccharification of pretreated biomass to obtain high concentrations of fermentable sugars are provided. Specifically, a process was developed that uses a fed batch approach with particle size reduction to provide a high dry weight of biomass content enzymatic saccharification reaction, which produces a high sugars concentration hydrolysate, using a low cost reactor system.

Hennessey, Susan M. (Avondale, PA); Seapan, Mayis (Landenberg, PA); Elander, Richard T. (Evergreen, CO); Tucker, Melvin P. (Lakewood, CO)

2010-10-05T23:59:59.000Z

125

Improving efficiency of high-concentrator photovoltaics by cooling with  

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

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

126

1 Copyright 2011 by ASME MATERIAL OPTIMIZATION FOR CONCENTRATED SOLAR PHOTOVOLTAIC AND  

E-Print Network (OSTI)

photovoltaic and hot water co-generation based on various solar cell technologies and micro channel heat sinks. Concentrated solar Photovoltaic (PV) based on multi junction cells can yield around 35-40% efficiency is moderate [3] in comparison to the concentrated solar photovoltaic, for which multi-junction cells

127

Energy Basics: Photovoltaic Cell Structures  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

128

Energy Basics: Photovoltaic Cell Performance  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

129

Energy Basics: Photovoltaic Cell Materials  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

130

ARM - Measurement - Organic Carbon Concentration  

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

govMeasurementsOrganic Carbon Concentration govMeasurementsOrganic Carbon Concentration ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Organic Carbon Concentration The concentration of carbon bound in organic compounds. Categories Aerosols Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments ACSM : Aerosol Chemical Speciation Monitor Field Campaign Instruments AEROSCARBON : Aerosol Carbon Analyzer AEROSMASSSPEC : Aerosol Mass Spectrometer Datastreams AOS : Aerosol Observing System Datastreams

131

Carbothermic Reduction of Niobium Concentrate  

Science Conference Proceedings (OSTI)

Abstract Scope, Ferro Niobium is produced by aluminothermic reduction of the ... However, the niobium concentrate has impurities, such as phosphorus, lead and tin, ... Phase Transformation of Andalusite-Mullite and Its Fiber Reinforcement to ...

132

Concentrated solar power on demand  

E-Print Network (OSTI)

This thesis describes a new concentrating solar power central receiver system with integral thermal storage. Hillside mounted heliostats direct sunlight into a volumetric absorption molten salt pool, which also functions ...

Codd, Daniel Shawn

2011-01-01T23:59:59.000Z

133

Maximally concentrating optics for photovoltaic solar energy conversion  

DOE Green Energy (OSTI)

Use of a two-stage concentrator with a fresnel lens primary and a nonimaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. Some preliminary ray trace studies have shown that with planar lenses, an increase in angular acceptance for a given geometric concentration to about 2/3 of the maximum theoretical limit can be achieved. To demonstrate this, two preprototype concentrators, each having a geometric concentration of 248:1 for a 0.635cm (0.25 inch) diameter cell, have been designed, built, and tested. Measurements of the angular response show an acceptance of 8[degrees] (full angle) which is drastically better than the 1[degrees]--2[degrees] achievable without a secondary, and is in excellent agreement with the ray trace predictions. For these preprototypes, passive cooling was sufficient to prevent any thermal problems for both the cell and secondary. No problems associated with nouuniform cell illumination were found, as evidenced by the fill factor of 71%--73% measured under concentration. Initial measurements of the system electrical efficiency lie in the range 7.5%--9.9% for a variety of individual cells.

O'Gallagher, J.J.

1985-03-07T23:59:59.000Z

134

RECALIBRATION OF H CANYON ONLINE SPECTROPHOTOMETER AT EXTENDED URANIUM CONCENTRATION  

SciTech Connect

The H Canyon online spectrophotometers are calibrated for measurement of the uranium and nitric acid concentrations of several tanks in the 2nd Uranium Cycle.[1] The spectrometers, flow cells, and prediction models are currently optimized for a process in which uranium concentrations are expected to range from 0-15 g/L and nitric acid concentrations from 0.05-6 M. However, an upcoming processing campaign will involve 'Super Kukla' material, which has a lower than usual enrichment of fissionable uranium. Total uranium concentrations will be higher, spanning approximately 0-30 g/L U, with no change in the nitric acid concentrations. The new processing conditions require the installation of new flow cells with shorter path lengths. As the process solutions have a higher uranium concentration, the shorter path length is required to decrease the absorptivity to values closer to the optimal range for the instrument. Also, new uranium and nitric acid prediction models are required to span the extended uranium concentration range. The models will be developed for the 17.5 and 15.4 tanks, for which nitric acid concentrations will not exceed 1 M. The restricted acid range compared to the original models is anticipated to reduce the measurement uncertainty for both uranium and nitric acid. The online spectrophotometers in H Canyon Second Uranium Cycle were modified to allow measurement of uranium and nitric acid for the Super Kukla processing campaign. The expected uranium concentrations, which are higher than those that have been recently processed, required new flow cells with one-third the optical path length of the existing cells. Also, new uranium and nitric acid calibrations were made. The estimated reading uncertainties (2{sigma}) for Tanks 15.4 and 17.5 are {approx}5% for uranium and {approx}25% for nitric acid.

Lascola, R

2008-10-29T23:59:59.000Z

135

NREL: Concentrating Solar Power Research - Concentrating Solar Power  

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

Concentrating Solar Power Resource Maps Concentrating Solar Power Resource Maps These direct-normal solar radiation maps-filtered by solar resource and land availability-identify the most economically suitable lands available for deploying of large-scale concentrating solar power plants in the southwestern United States. Each of the following seven states, as well as the southwestern U.S. region, has two maps: the left and right maps represent analyses excluding land with slopes >1% and >3%, respectively. Lower-resolution jpg versions are available below; much higher-resolution pdf files, suitable for plotting large-scale posters, can be requested. You can also access an unfiltered direct-normal solar radiation map of the southwestern United States. Download Adobe Reader. Southwestern U.S.

136

Alpha Solarco`s Photovoltaic Concentrator Development program  

DOE Green Energy (OSTI)

This report details the work done under Sandia`s Photovoltaic Concentrator Development contract, funded jointly by Alpha Solarco and the US Department of Energy. It discusses improvements made to the cell assembly and module design of Alpha Solarco`s point-focus, high-concentration photovoltaic module. The goals of this effort were to increase the module efficiency, reduce the manufacturing cost of the cell assembly, and increase product reliability. Redesign of the secondary optical element achieved a 4 percent increase in efficiency due to better cell fill factors and offtrack performance. New, lower cost materials were identified for the secondary optical element, the optical couple between the secondary optical element and the cell, and the cell assembly electrical insulator. Manufacturing process improvements and test equipment are also discussed.

Anderson, A.; Bailor, B.; Carroll, D. [Alpha Solarco, Inc., Phoenix, AZ (United States)] [and others

1995-10-01T23:59:59.000Z

137

ARM - Measurement - Trace gas concentration  

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

govMeasurementsTrace gas concentration govMeasurementsTrace gas concentration ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Trace gas concentration The amount per unit volume of trace gases other than carbon dioxide, ozone and water vapor, typically measured in conjunction with in situ aerosol measurements, e.g. carbon monoxide, nitrogen oxides, sulfur dioxide. Categories Atmospheric Carbon, Atmospheric State Instruments The above measurement is considered scientifically relevant for the following instruments. Refer to the datastream (netcdf) file headers of each instrument for a list of all available measurements, including those recorded for diagnostic or quality assurance purposes. ARM Instruments CO : Carbon Monoxide Mixing Ratio System

138

Concentrating Solar Power | Department of Energy  

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

Concentrating Solar Power Concentrating Solar Power August 20, 2013 - 4:38pm Addthis Text Version This solar concentrator has a fixed-focus faceted dish with a concentration of...

139

Solar Tracing Sensors for Maximum Solar Concentrator ...  

Concentrating Solar Power (CSP) relies on thermodynamic processes to convert concentrated light into useful forms of energy. Accurate sun tracking ...

140

Concentrating solar collector: technical note  

DOE Green Energy (OSTI)

The Acurex Model 3002 concentrator is a reflecting parabolic trough collector designed to heat liquids or gases to temperatures between 140/sup 0/F and 350/sup 0/F. The cost effectiveness, performance, reliability, and technical description of the collector are presented.

Not Available

1984-01-01T23:59:59.000Z

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


141

Photovoltaic concentrator with plastic-film reflector. Final report  

DOE Green Energy (OSTI)

A 4m diameter reflective film, parabolic dish concentrator proposed for use with a photovoltaic array has been designed, fabricated, and tested. The concentrator is made from aluminized film gores (wedge shaped pieces) that are taped together along their edges to form a dish. The shape of the dish is maintained by a pressure difference between the front and back. The deep dish was designed to illuminate a cylindrical receiver populated by solar cells with a geometric concentration ratio of 145. Three full scale dishes were made in sequence, each using improvements suggested by the previous design. They were tested with a laser to determine surface errors and flux uniformity on the target.

Not Available

1982-06-01T23:59:59.000Z

142

Correlations in Characteristic Data of Concentrator Photovoltaics (Poster)  

SciTech Connect

This study is motivated by a reported 1-2% infant mortality rate in concentrator photovoltaic cell assemblies. Approximately 650 bare III-V multi-junction PV cells were initially characterized via electroluminescence imaging and both light and dark current-voltage responses were recorded. The cells were then packaged into receivers and their IV response again evaluated both before and after an outdoor high concentration exposure of at least four hours above 750 DNI. Correlations exist between the initial dark IV characteristic and artifacts found in the EL image. Initial results also suggest that artifacts observed in the bare cell may serve as an indicator for early on-sun degradation, though may not be able to predict the infant mortality population.

Sweet, C.; Bosco, N.; Kurtz, S.

2011-02-01T23:59:59.000Z

143

Cylindrical acoustic levitator/concentrator  

DOE Patents (OSTI)

A low-power, inexpensive acoustic apparatus for levitation and/or concentration of aerosols and small liquid/solid samples having particulates up to several millimeters in diameter in air or other fluids is described. It is constructed from a commercially available, hollow cylindrical piezoelectric crystal which has been modified to tune the resonance frequency of the breathing mode resonance of the crystal to that of the interior cavity of the cylinder. When the resonance frequency of the interior cylindrical cavity is matched to the breathing mode resonance of the cylindrical piezoelectric transducer, the acoustic efficiency for establishing a standing wave pattern in the cavity is high. The cylinder does not require accurate alignment of a resonant cavity. Water droplets having diameters greater than 1 mm have been levitated against the force of gravity using; less than 1 W of input electrical power. Concentration of aerosol particles in air is also demonstrated.

Kaduchak, Gregory (Los Alamos, NM); Sinha, Dipen N. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

144

Maximally concentrating optics for photovoltaic solar energy conversion  

DOE Green Energy (OSTI)

The use of a two-stage concentrator with a fresnel lens primary and a non-imaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. This new design has a much larger acceptance angle than the conventional lens-cell concentrating system. In the continuation of this research, an optimally designed prototype which employs a 13.6-cm diameter flat fresnel tons as the primary focusing device, a dielectric compound hyperbolic concentrator (DCHC) as secondary and a 1-cm diameter high-concentration cell for electricity conversion has been built, tested and analyzed. Measurements under sunlight show that it has an angular acceptance of [plus minus]3.6 degrees, which is dramatically better than the [plus minus]0.5 degree achievable without a secondary concentrator. This performance agrees well with theoretical ray-tracing predictions. The secondary shows an optical efficiency of (91[plus minus]2)% at normal incidence. Combining with the primary fresnel tens which has an optical efficiency of (82[plus minus]2)%, tho two-stage system yields a total optical efficiency of (7l[plus minus]2)%. The measurement of the system electrical performance yielded a net electrical efficiency of 11.9%. No problems associated with non-uniform cell illumination were found, as evidenced by the excellent fill factor of (79[plus minus]2)% measured under concentration. The secondary geometrical properties and the optimal two-stage design procedures for various primary- cell combinations were systematical studied. A general design principle has been developed.

Winston, R.; O'Gallagher, J.; Ning, X.

1986-02-27T23:59:59.000Z

145

Electrochemical cell  

DOE Patents (OSTI)

An electrochemical cell having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a .beta." alumina electrolyte and NaAlCl.sub.4 or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose.

Redey, Laszlo I. (Downers Grove, IL); Vissers, Donald R. (Naperville, IL); Prakash, Jai (Downers Grove, IL)

1994-01-01T23:59:59.000Z

146

Enclosed, off-axis solar concentrator  

SciTech Connect

A solar concentrator including a housing having receiving wall, a reflecting wall and at least two end walls, the receiving, reflecting and end walls defining a three-dimensional volume having an inlet, wherein a vertical axis of the housing is generally perpendicular to the inlet, a receiver mounted on the receiving wall of the housing, the receiver including at least one photovoltaic cell, wherein a vertical axis of the receiver is disposed at a non-zero angle relative to the vertical axis of the housing, at least one clip disposed on the reflecting wall an optical element received within the three-dimensional volume, the optical element including at least one tab, the tab being engaged by the clip to align the optical element with the receiver, and a window received over the inlet to enclose the housing.

Benitez, Pablo; Grip, Robert E; Minano, Juan C; Narayanan, Authi A; Plesniak, Adam; Schwartz, Joel A

2013-11-26T23:59:59.000Z

147

Concentrating Solar Power Program overview  

DOE Green Energy (OSTI)

Over the last decade, the US solar thermal industry has established a track record in the power industry by building and operating utility-scale power plants with a combined rated capacity of 354 megawatts (MW). The technology used in these power plants is based on years of research and development (R and D), much of it sponsored by the US Department of Energy (DOE). DOE`s Concentrating Solar Power (CSP) Program is collaborating with its partners in the private sector to develop two new solar technologies -- power towers and dish/engines -- to meet the huge commercial potential for solar power.

NONE

1998-04-01T23:59:59.000Z

148

Mathematical modeling of solar concentrators  

DOE Green Energy (OSTI)

A computational capability that models the operation of any solar energy collector that uses flux concentrators is a valuable aid in the planning, design, construction, calibration, safety analysis, and operation of the system. In addition to the usual optical considerations, the model should treat such imperfections as reflecting-surface slope errors, suntracking and alignment errors, and mirror-focusing errors. It should properly account for the angular distribution of incoming sun rays and the effects of atmospheric transmission on this distribution. A model with these capabilities is described, and two computer programs for implementing it are illustrated.

Biggs, F.; Vittitoe, C.N.

1976-01-01T23:59:59.000Z

149

Cost effective manufacturing of the SEA 10X concentrator array  

DOE Green Energy (OSTI)

This report describes a low-cost, mass-producible 10X concentrator system that has been claimed to produce electricity at $0.04/kWh. It details changes in manufacturing techniques that could produce a concentrator system at a selling price of $0.71/W. (A simple design and a minimum number of parts and manufacturing steps reduced production costs.) Present production techniques, changes to improve these techniques, impediments to changes, and solutions to the impediments are described. This 10X concentrator system uses available components and manufacturing processes and one-sun solar cells in conjunction with inexpensive plastic lenses to generate about eight times the amount of electricity normally produced by these cells.

Kaminar, N.; McEntee, J.; Curchod, D. (Solar Engineering Applications Corp., San Jose, CA (United States))

1991-11-01T23:59:59.000Z

150

Gas and Particulate Concentration Measurements and ...  

Science Conference Proceedings (OSTI)

... to the species of interest as gas concentration standards ... for low concentrations and toxic and reactive gases. ... data set correlating liquid-phase fuels ...

2012-10-01T23:59:59.000Z

151

Concentrating Solar Power Facilities | Department of Energy  

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

Concentrating Solar Power Facilities Concentrating Solar Power Facilities Florida Hawaii Southwest U.S. Addthis Browse By Topic TOPICS Energy Efficiency ---Home Energy Audits...

152

Federal Energy Management Program: Concentrating Solar Power...  

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

Concentrating Solar Power Resources and Technologies to someone by E-mail Share Federal Energy Management Program: Concentrating Solar Power Resources and Technologies on Facebook...

153

Planar micro-optic solar concentration  

E-Print Network (OSTI)

connects to a single photovoltaic cell. We refer to thisplane. Optimized photovoltaic cells can be interleaved on aand expenses. Photovoltaic cells are commonly connected into

Karp, Jason Harris

2010-01-01T23:59:59.000Z

154

SunShot Initiative: Concentrating Solar Power  

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

Concentrating Solar Power to Concentrating Solar Power to someone by E-mail Share SunShot Initiative: Concentrating Solar Power on Facebook Tweet about SunShot Initiative: Concentrating Solar Power on Twitter Bookmark SunShot Initiative: Concentrating Solar Power on Google Bookmark SunShot Initiative: Concentrating Solar Power on Delicious Rank SunShot Initiative: Concentrating Solar Power on Digg Find More places to share SunShot Initiative: Concentrating Solar Power on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards Staff Photovoltaics Systems Integration Balance of Systems Concentrating Solar Power SunShot CSP Team Learn more about the SunShot concentrating solar power program staff by visiting the team's profile pages. Argonne National Laboratory Argonne National Laboratory

155

Concentrating Solar Power: Technology Overview  

Science Conference Proceedings (OSTI)

Concentrating Solar Power (CSP) has the potential to contribute significantly to the generation of electricity by renewable energy resources in the U.S.. Thermal storage can extend the duty cycle of CSP beyond daytime hours to early evening where the value of electricity is often the highest. The potential solar resource for the southwest U.S. is identified, along with the need to add power lines to bring the power to consumers. CSP plants in the U.S. and abroad are described. The CSP cost of electricity at the busbar is discussed. With current incentives, CSP is approaching competiveness with conventional gas-fired systems during peak-demand hours when the price of electricity is the highest. It is projected that a mature CSP industry of over 4 GWe will be able to reduce the energy cost by about 50%, and that U.S. capacity could be 120 GW by 2050.

Mehos, M.

2008-01-01T23:59:59.000Z

156

Parabolic concentrating collector: a tutorial  

DOE Green Energy (OSTI)

A tutorial overview of point-focusing parabolic collectors is presented. Optical and thermal characteristics of such collectors are discussed. Data representing typical achievable collector efficiencies are presented and the importance of balancing collector cost with concentrator quality is argued through the development of a figure of merit for the collector. The impact of receiver temperature on performance is assessed and the general observation made that temperatures much in excess of 1500 to 2000/sup 0/F can actually result in decreased performance. Various types of two-axis tracking collectors are described, including the standard parabolic deep dish, Cassegrainian and Fresnel, as well as two forms of fixed mirrors with articulating receivers. The present DOE program to develop these devices is briefly discussed, as are present and projected costs for these collectors. Pricing information is presented for the only known commercial design available on the open market.

Truscello, V.C.

1979-02-15T23:59:59.000Z

157

Advanced evacuated tubular concentrator research  

SciTech Connect

Previous research projects led to the conceptual development and proof-of-concept of an advanced evacuated concentrating solar collector tube. The basic idea involves the integration of a nonimaging Compound Parabolic Concentrator (CPC) inside an evacuated tube and coupled to a spectrally selective absorber. An experimental panel of these tubes achieved the highest operating efficiency at high temperatures ever measured with a non-tracking stationary solar collector. Subsequent studies have indicated that a mass-producible collector, incorporating the same concepts, can be developed which will deliver excellent performance across a broad range of temperatures, extending from about 50{degrees}C (suitable for domestic hot water and space heating) to well above 200{degrees}C (suitable for space cooling, process steam and many other end uses). Some form of advanced Integrated CPC (ICPC) remains the only simple and effective method for delivering solar thermal energy efficiently throughout the temperature range from 50{degrees}C to about 300{degrees}C without tracking. It has the potential to make practical and economical several cooling technologies which are otherwise not viable. In addition to its potential for driving cooling systems, this technology also provides a highly versatile solar source for virtually all thermal end uses including general purpose space and domestic hot water heating as well as industrial process heat. Research efforts have been directed towards designing and prototyping a manufacturable version of such a collector tube. We have been pursuing several paths. These include: (1) a small tube version, 52mm in diameter, based on the use of the T-17 commercially produced fluorescent glass tubing, which is the largest size lamp tubing produced in high volume in the United States, and (2) a large tube version, 125mm in diameter, compatible with the commercial design manufactured until recently by Corning France (the CORTEC collector).

Winston, R.; O'Gallagher, J.J.

1992-06-01T23:59:59.000Z

158

Energy Basics: Photovoltaic Cell Quantum Efficiency  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

159

Energy Basics: Crystalline Silicon Photovoltaic Cells  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

160

Energy Basics: Photovoltaic Cell Conversion Efficiency  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

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


161

Energy Conversion – Photovoltaic, Concentrating Solar Power, and ...  

Science Conference Proceedings (OSTI)

About this Symposium. Meeting, Materials Science & Technology 2012. Symposium, Energy Conversion – Photovoltaic, Concentrating Solar Power, and  ...

162

Fundamental Limits to Position Determination by Concentration Gradients  

E-Print Network (OSTI)

Position determination in biological systems is often achieved through protein concentration gradients. Measuring the local concentration of such a protein with a spatially-varying distribution allows the measurement of position within the system. In order for these systems to work effectively, position determination must be robust to noise. Here, we calculate fundamental limits to the precision of position determination by concentration gradients due to unavoidable biochemical noise perturbing the gradients. We focus on gradient proteins with first order reaction kinetics. Systems of this type have been experimentally characterised in both developmental and cell biology settings. For a single gradient we show that, through time-averaging, great precision can potentially be achieved even with very low protein copy numbers. As a second example, we investigate the ability of a system with oppositely directed gradients to find its centre. With this mechanism, positional precision close to the centre improves more slowly with increasing averaging time, and so longer averaging times or higher copy numbers are required for high precision. For both single and double gradients, we demonstrate the existence of optimal length scales for the gradients, where precision is maximized, as well as analyzing how precision depends on the size of the concentration measuring apparatus. Our results provide fundamental constraints on the positional precision supplied by concentration gradients in various contexts, including both in developmental biology and also within a single cell.

Filipe Tostevin; Pieter Rein ten Wolde; Martin Howard

2007-04-26T23:59:59.000Z

163

Production of fullerenes using concentrated solar flux  

SciTech Connect

A method of producing soot containing high amounts of fullerenes comprising: providing a primary concentrator capable of impingement of a concentrated beam of sunlight onto a carbon source to cause vaporization of carbon and subsequent formation of fullerenes, or providing a solar furnace having a primary concentrator with a focal point that concentrates a solar beam of sunlight; providing a reflective secondary concentrator having an entrance aperture and an exit aperture at the focal point of the solar furnace; providing a carbon source at the exit aperture of the secondary concentrator; supplying an inert gas over the carbon source to keep the secondary concentrator free from vaporized carbon; and impinging a concentrated beam of sunlight from the secondary concentrator on the carbon source to vaporize the carbon source into a soot containing high amounts of fullerenes.

Fields, Clark L. (Greeley, CO); Pitts, John Roland (Lakewood, CO); King, David E. (Lakewood, CO); Hale, Mary Jane (Golden, CO); Bingham, Carl E. (Denver, CO); Lewandowski, Allan A. (Evergreen, CO)

2000-01-01T23:59:59.000Z

164

Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Poster)  

DOE Green Energy (OSTI)

Polymeric encapsulation materials are typically used in concentrating photovoltaic (CPV) modules to protect the cell from the field environment. Because it is physically located adjacent to the cell, the encapsulation is exposed to a high optical flux, often including light in the ultraviolet (UV) and infrared (IR) wavelengths. The durability of encapsulants used in CPV modules is critical to the technology, but is presently not well understood. This work seeks to identify the appropriate material types, field-induced failure mechanisms, and factors of influence (if possible) of polymeric encapsulation. These results will ultimately be weighed against those of future qualification and accelerated life test procedures.

Miller, D. C.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

2011-02-01T23:59:59.000Z

165

Effects of CCN Concentrations on Stratus Clouds  

Science Conference Proceedings (OSTI)

Comparisons between cloud-base CCN concentrations and cloud droplet concentrations in stratus clouds over San Diego and 100 km out to sea showed a positive correlation. The supersaturation in these clouds, as derived from the matching of the CCN ...

James G. Hudson

1983-02-01T23:59:59.000Z

166

Electrochemical cell  

DOE Patents (OSTI)

An electrochemical cell is described having an alkali metal negative electrode such as sodium and a positive electrode including Ni or transition metals, separated by a [beta] alumina electrolyte and NaAlCl[sub 4] or other compatible material. Various concentrations of a bromine, iodine and/or sulfur containing additive and pore formers are disclosed, which enhance cell capacity and power. The pore formers may be the ammonium salts of carbonic acid or a weak organic acid or oxamide or methylcellulose. 6 figs.

Redey, L.I.; Vissers, D.R.; Prakash, J.

1994-08-23T23:59:59.000Z

167

Estimating Contaminant Release Concentrations from Hanford ...  

& Transport Model Long-Term Performance Assessment ... sludge provide upper limit on future releases. 9 Metals Concentrations in Hanford Tank ...

168

NREL's Concentrated Solar Radiation User Facility  

DOE Green Energy (OSTI)

Declared a national user facility in 1993, NREL's Concentrated Solar Radiation User Facility (CSR) allows industry, government, and university researchers to examine the effects and applications of as much as 50,000 suns of concentrated solar radiation using a High-Flux Solar Furnace and long-term exposure using an ultraviolet (UV) concentrator.

Lewandowski, A.

1999-09-01T23:59:59.000Z

169

Preliminary evaluation of two-element optical concentrators for use in solar photovoltaic systems  

DOE Green Energy (OSTI)

The objective of this program was: to evaluate for photovoltaic applications the use of the compound parabolic concentrator design as a field collector--in conjunction with a primary focusing concentrator. The primary focusing concentrator may be a parabolic reflector, an array of Fresnel mirrors, a Fresnel lens, or some other type; Select several candidate configurations of such compound systems (focusing concentrators/CPC field collectors); Perform an analytic evaluation of the technical performance of these systems; and identify the most promising configurations and perform a cost effectiveness study pertinent to coupling CPC concentrators to solar cells. (WDM)

None

1975-06-30T23:59:59.000Z

170

Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Presentation)  

DOE Green Energy (OSTI)

Many concentrating photovoltaic (CPV) systems use a polymeric encapsulant to couple and optical component and/or coverglass to the cell. In that location, the encapsulation improves the transmission of concentrated optical flux through interface(s), while protecting the cell from the environment. The durability of encapsulation materials, however, is not well established relative to the desired service life of 30 years. Therefore, we have initiated a screen test to identify the field-induced failure modes for a variety of popular PV encapsulation materials. An existing CPV module (with no PV cells present) was modified to accommodate encapsulation specimens. The module (where nominal concentration of solar flux is 500x for the domed-Fresnel design) has been mounted on a tracker in Golden, CO (elevation 1.79 km). Initial results are reported here for 18 months cumulative exposure, including the hottest and coldest months of the past year. Characteristics observed at intervals during that time include: visual appearance, direct and hemispherical transmittance, and mass. Degradation may be assessed from subsequent analysis (including yellowness index and cut-on frequency) relative to the ambient conditions present during field exposure. The fluorescence signature observed of all the silicone specimens is examined here, including possible factors of causation -- the platinum catalyst used in the addition cured materials as well as the primer used to promote adhesion to the quartz substrate and superstrate.

Miller, D. C.; Muller, M.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

2012-03-01T23:59:59.000Z

171

Effect of lactose concentration on batch production of ethanol from cheese whey using Candida pseudotropicalis  

SciTech Connect

The effect of lactose concentration on growth of Candida pseudotropicalis and ethanol production from cheese whey under batch conditions was investigated. Four initial lactose concentrations ranging from 50 to 200 g/L (5 to 20% wt/vol) were used. High concentration of lactose had an inhibitory effect on the specific growth rate, lactose utilization rate, and ethanol production rate. The maximum cell concentration was influenced by the initial substrate concentration as well as ethanol concentration. Inhibition of ethanol production was more pronounced at higher initial lactose concentrations. The maximum ethanol yield (96.6% of the theoretical yield) was achieved with the 100 g/L initial substrate concentration. The results indicated that pH control during alcohol fermentation of cheese whey is not necessary. 41 refs., 12 figs., 1 tab.

Ghaly, A.E.; El-Taweel, A.A. [Technical Univ. of Nova Scotia, Halifax (Canada)

1995-07-01T23:59:59.000Z

172

Analysis of static and quasi-static cross compound parabolic concentrators  

SciTech Connect

Static and quasi-static concentrators present interesting characteristics for obtaining photovoltaic solar energy. In this work we study the characteristics of the crossed compound parabolic concentrator, formed by the intersection of two cyclindrical compound parabolic concentrators (CPC). Bifacial cells are used in this concentrator as a requirement for obtaining higher concentrations. Static and quasi-static concentrators see the sun as an extended source, so a simplified source model of radiance for the sky of Madrid is used. The figures of merit of a lossless concentrator are studied and the most important parameters influencing its optical behavior are discussed. We conclude that these concentrators obtain results that lead to a decrease in the cost of photovoltaic energy.

Molledo, A.G.; Luque, A.

1984-06-15T23:59:59.000Z

173

Proppant concentrator boosts foam frac effectiveness  

Science Conference Proceedings (OSTI)

A recently introduced propant concentrator appears to be reducing downtime and enhancing the overall effectiveness and practicality of foam fracturing. The basic purpose behind the proppant concentrator is to provide a method to allow higher proppant concentrations to be run in foam stimulation treatments. A concentrator removes liquid while pumping to allow a higher proppant load to be delivered to the well. This is accomplished by injecting the fluid/proppant slurry, which has been preblended, and passing it through a standard screen or centrifugal device. This allows removal of up to 50% of the liquid portion of the slurry and achieves a doubling of the proppant concentration prior to being foamed.

Not Available

1981-11-01T23:59:59.000Z

174

Nanofluidic Concentration Device for Biomolecules Utilizing Ion Concentration Polarization: Theory, Fabrication, and Applications  

E-Print Network (OSTI)

Recently, a new type of electrokinetic concentration devices has been developed in a microfluidic chip format, which allows efficient trapping and concentration of biomolecules by utilizing ion concentration polarization ...

Kim, Sung Jae

175

Concentrating solar power | Open Energy Information  

Open Energy Info (EERE)

Concentrating solar power Concentrating solar power (Redirected from Concentrating Solar Power) Jump to: navigation, search Concentrating Solar Power Basics (The following text is derived from NREL's concentrating solar power information page.)[1] Concentrating solar power (CSP) offers a utility-scale, firm, dispatchable renewable energy option that can help meet our nation's demand for electricity. CSP plants produce power by first using mirrors to focus sunlight to heat a working fluid. Ultimately, this high-temperature fluid is used to spin a turbine or power an engine that drives a generator. And the final product is electricity. Smaller CSP systems can be located directly where the power is needed. Larger, utility-scale CSP applications provide hundreds of megawatts of electricity for the power grid. Both linear concentrator and power tower

176

Concentrating solar power | Open Energy Information  

Open Energy Info (EERE)

Concentrating solar power Concentrating solar power (Redirected from - Concentrating Solar Power) Jump to: navigation, search Concentrating Solar Power Basics (The following text is derived from NREL's concentrating solar power information page.)[1] Concentrating solar power (CSP) offers a utility-scale, firm, dispatchable renewable energy option that can help meet our nation's demand for electricity. CSP plants produce power by first using mirrors to focus sunlight to heat a working fluid. Ultimately, this high-temperature fluid is used to spin a turbine or power an engine that drives a generator. And the final product is electricity. Smaller CSP systems can be located directly where the power is needed. Larger, utility-scale CSP applications provide hundreds of megawatts of electricity for the power grid. Both linear concentrator and power tower

177

Airport Solar Photovoltaic Concentrator Project. Phase 1 - final report, June 1, 1978-February 28, 1979  

DOE Green Energy (OSTI)

The system design, analysis, and specification, site preparation, and operation and evaluation plan for a 500 kWe photovoltaic power supply to be located at the Phoenix Sky Harbor International Airport in Phoenix, Arizona, are presented. The solar cell arrays are concentrator silicon solar cells with tracking 70X Cassegrain-type concentrators. The power conditioning system, tracking system, and control systems are described in detal. Environmental impact studies are described. Component specifications and drawings are included. (WHK)

Not Available

1979-12-01T23:59:59.000Z

178

Terrestrial photovoltaic power systems with sunlight concentration. Annual progress report, January 1, 1975--December 31, 1975  

DOE Green Energy (OSTI)

This annual report is for the second year of a program to investigate the characteristics of the components and the total system using sunlight concentrated onto solar cells. The second year was primarily to experimentally investigate the conclusions of the first year of analytical studies. Cells have been fabricated that are designed for different intensities. Typically the efficiency of a cell will increase from its 11 percent at AM1 peak to efficiency at the designed concentration level and return to its initial efficiency at about 3 times its designed concentration level. The developed cells have been tested under high intensity simulators and in concentrated sunlight and have shown to have the predicted response. The experimental testing of passive cooling limitations for cooling cells with just finned arrangements in the back of the cell has been completed in the controlled environment of a wind tunnel. These experiments have confirmed the heat transfer coefficients that had been used in the analytical studies. Testing was done to collect heat transfer coefficients for actual wind conditions and these data show good agreement with the controlled wind tunnel data. Four photovoltaic/concentrator system experiments have been started with CR of about 3, 10, 25, and 100. System analysis has indicated that photovoltaic concentration systems may be attractive in low solar irradiation areas such as Cleveland.

Backus, C.E.

1976-01-31T23:59:59.000Z

179

Concentrating Solar Power Basics | Department of Energy  

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

Basics Basics Concentrating Solar Power Basics August 20, 2013 - 4:38pm Addthis Text Version This solar concentrator has a fixed-focus faceted dish with a concentration of about 250 suns. This system can be used for large fields connected to the utility grid, hydrogen generation, or water pumping. Credit: Science Applications International Corporation / PIX 13464 Concentrating solar power (CSP) technologies use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat. This thermal energy can then be used to produce electricity via a steam turbine or heat engine that drives a generator. Concentrating solar power offers a utility-scale, firm, dispatchable renewable energy option that can help meet our nation's demand for

180

Automated Micro-Tracking Planar Solar Concentrators.  

E-Print Network (OSTI)

?? One aim of solar concentrators is to reduce the cost of a solar power systems by reducing the amount of expensive semiconductor used in… (more)

Hallas, Justin Matthew

2011-01-01T23:59:59.000Z

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


181

Modeling Carbon Concentration Profiles in Austenitic Stainless ...  

Science Conference Proceedings (OSTI)

Presentation Title, Modeling Carbon Concentration Profiles in Austenitic Stainless Steels Carburized at Low Temperatures. Author(s), Gary M. Michal, Xiaoting ...

182

Production mechanisms, number concentration, size distribution...  

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

Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002asl2.441 Meeting Report Production mechanisms, number concentration, size distribution, chemical composition, and...

183

Status of photovoltaic concentrator modules and systems  

DOE Green Energy (OSTI)

Several leading line- and point-focus photovoltaic concentrator system development programs are reviewed, including those by ENTECH, SEA Corporation, AMONIX, and Alpha Solarco. Concentrating collectors and trackers are gaining maturity and reaching product status as designs are made more manufacturable and reliable. Utilities are starting to take notice of this emerging technology, and several privately-funded utility installations are underway. Several advantages are offered by concentrators, including low system and capital cost and rapid production ramp-up. These are discussed along with issues generally raised concerning concentrator technology.

Maish, A.B.

1994-04-01T23:59:59.000Z

184

Gravity Gold Concentration at Newmont Mining  

Science Conference Proceedings (OSTI)

Abstract Scope, The process of gold recovery by gravity concentration is incorporated ... Energy Management Planning, Following the ISO 50001 Draft Standard.

185

PV FAQs: What's New in Concentrating PV?  

DOE Green Energy (OSTI)

This publication, one in a series of PV FAQs, addresses concentrating PV: what it is, how it works, the challenges it faces, recent breakthroughs, and its future direction.

Not Available

2005-02-01T23:59:59.000Z

186

A combined microfluidic/dielectrophoretic microorganism concentrator  

E-Print Network (OSTI)

This thesis presents the development of a high-throughput microfluidic microorganism concentrator for pathogen detection applications. Interdigitated electrodes lining the bottom of the channel use positive dielectrophoretic ...

Gadish, Nitzan

2005-01-01T23:59:59.000Z

187

NREL: Concentrating Solar Power Projects Home Page  

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

of concentrating solar power plants. Activities include testing large-scale systems and developing advanced technologies, components, instrumentation, and analysis techniques....

188

NREL: Concentrating Solar Power Research - Technology Basics  

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

Technology Basics Concentrating solar power (CSP) technologies can be a major contributor to our nation's future need for new, clean sources of energy, particularly in the Western...

189

Concentrating Solar Power: Energy from Mirrors  

DOE Green Energy (OSTI)

This fact sheet explains how concentrating solar power technology works and the three types of systems in development today: trough, dish, and central receiver.

Poole, L.

2001-02-27T23:59:59.000Z

190

Alignment method for parabolic trough solar concentrators  

DOE Patents (OSTI)

A Theoretical Overlay Photographic (TOP) alignment method uses the overlay of a theoretical projected image of a perfectly aligned concentrator on a photographic image of the concentrator to align the mirror facets of a parabolic trough solar concentrator. The alignment method is practical and straightforward, and inherently aligns the mirror facets to the receiver. When integrated with clinometer measurements for which gravity and mechanical drag effects have been accounted for and which are made in a manner and location consistent with the alignment method, all of the mirrors on a common drive can be aligned and optimized for any concentrator orientation.

Diver, Richard B. (Albuquerque, NM)

2010-02-23T23:59:59.000Z

191

NREL: Concentrating Solar Power Research - Webmaster  

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

Your name: Your email address: Your message: Send Message Printable Version Concentrating Solar Power Research Home Projects Research Staff Working with Us Data & Resources...

192

A solar concentrating photovoltaic/thermal collector.  

E-Print Network (OSTI)

??This thesis discusses aspects of a novel solar concentrating photovoltaic / thermal (PV/T) collector that has been designed to produce both electricity and hot water.… (more)

Coventry, Joseph S

2008-01-01T23:59:59.000Z

193

Concentrating Solar Power (Revised) (Fact Sheet)  

SciTech Connect

The fact sheet summarizes the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

Not Available

2010-11-01T23:59:59.000Z

194

National Aeronautics and Space Administration Ultra-Light, Low-Cost Solar Concentrator Offers  

E-Print Network (OSTI)

Fresnel lenses for optical concentration, minimizing solar cell area, mass, and cost. The SLA has been of solar energy technologies and sustainable daylighting solutions. The company designs, manufacturers lenses focusing sunlight onto multi-junction solar cells mounted to thin carbon-fiber composite radiators

195

Definition: Concentrating solar power | Open Energy Information  

Open Energy Info (EERE)

Dictionary.png Dictionary.png Concentrating solar power Technologies that use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat. This thermal energy can then be used to produce electricity via a steam turbine or heat engine that drives a generator.[1][2] View on Wikipedia Wikipedia Definition . ]] File:El-v-01 ubt. jpeg Sustainable energy Renewable energy Anaerobic digestion Hydroelectricity · Geothermal Microgeneration · Solar Tidal · Wave · Wind Energy conservation Cogeneration · Energy efficiency Geothermal heat pump Green building · Passive Solar Sustainable transport Plug-in hybrids · Electric vehicles File:Terra- edge blur. png Environment Portal v · d · e Concentrated solar power (also called concentrating solar power, concentrated solar thermal, and CSP) systems use

196

Advanced photovoltaic concentrator system low-cost prototype module  

DOE Green Energy (OSTI)

This report describes the continued development of an extruded lens and the development of a PV receiver, both of which will be used in the Solar Engineering Applications Corporation (SEA) 10X concentrator. These efforts were pare of a pre-Concentrator Initiative Program. The 10X concentrator consists of an inexpensive, extruded linear Fresnel lens which focuses on one-sun cells which are adhesive-bonded to an anodized aluminum heat sink. Module sides are planned to be molded along with the lens and are internally reflective for improved on- and off-track performance. End caps with molded-in bearings complete the module. Ten modules are mounted in a stationary frame for simple, single-axis tracking in the east-west direction. This configuration an array, is shipped completely assembled and requires only setting on a reasonably flat surface, installing 4 fasteners, and hooking up the wires. Development of the 10-inch wide extruded lens involved one new extrusion die and a series of modifications to this die. Over 76% lens transmission was measured which surpassed the program goal of 75%. One-foot long receiver sections were assembled and subjected to evaluation tests at Sandia National Laboratories. A first group had some problem with cell delamination and voids but a second group performed very well, indicating that a full size receiver would pass the full qualification test. Cost information was updated and presented in the report. The cost study indicated that the Solar Engineering Applications Corporation concentrator system can exceed the DOE electricity cost goals of less than 6cents per KW-hr. 33 figs., 11 tabs.

Kaminar, N.R.; McEntee, J.; Curchod, D. (Solar Engineering Applications Corp., San Jose, CA (United States))

1991-09-01T23:59:59.000Z

197

Mercury concentrations in Maine sport fishes  

Science Conference Proceedings (OSTI)

To assess mercury contamination of fish in Maine, fish were collected from 120 randomly selected lakes. The collection goal for each lake was five fish of the single most common sport fish species within the size range commonly harvested by anglers. Skinless, boneless fillets of fish from each lake were composited, homogenized, and analyzed for total mercury. The two most abundant species, brook trout Salvelinus fontinalis and smallmouth bass Micropterus dolomieu, were also analyzed individually. The composite fish analyses indicate high concentrations of mercury, particularly in large and long-lived nonsalmonid species. Chain pickerel Esox niger, smallmouth bass, largemouth bass Micropterus salmoides, and white perch Morone americana had the highest average mercury concentrations, and brook trout and yellow perch Perca flavescens had the lowest. The mean species composite mercury concentration was positively correlated with a factor incorporating the average size and age of the fish. Lakes containing fish with high mercury concentrations were not clustered near known industrial or population centers but were commonest in the area within 150 km of the seacoast, reflecting the geographical distribution of species that contained higher mercury concentrations. Stocked and wild brook trout were not different in length or weight, but wild fish were older and had higher mercury concentrations. Fish populations maintained by frequent introductions of hatchery-produced fish and subject to high angler exploitation rates may consist of younger fish with lower exposure to environmental mercury and thus contain lower concentrations than wild populations.

Stafford, C.P. [Univ. of Maine, Orono, ME (United States); Haines, T.A. [Geological Survey, Orono, ME (United States)

1997-01-01T23:59:59.000Z

198

Heterojunction solar cells  

DOE Green Energy (OSTI)

A qualitative description of semiconductor/semiconductor heterojunction solar cells is given. The two groups of heterojunctions of greatest economic potential, very highly efficient cells for concentrator applications and moderately efficient thin film cells for flat plates, are described with examples. These examples illustrate the role of heterojunctions in surface passivation, monolithic multijunction devices, devices with semiconductors of only one conductivity type, and low-temperature fabrication techniques.

Wagner, S.

1978-01-01T23:59:59.000Z

199

Energy Basics: Photovoltaic Electrical Contacts and Cell Coatings  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Cells Systems Concentrating Solar...

200

Entanglement concentration of three-partite states  

Science Conference Proceedings (OSTI)

We investigate the concentration of multiparty entanglement by focusing on a simple family of three-partite pure states, superpositions of Greenberger-Horne-Zeilinger states and singlets. Despite the simplicity of the states, we show that they cannot be reversibly concentrated by the standard entanglement concentration procedure, to which they seem ideally suited. Our results cast doubt on the idea that for each N there might be a finite set of N-party states into which any pure state can be reversibly transformed. We further relate our results to the concept of locking of entanglement of formation.

Groisman, Berry [HH Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Linden, Noah [Department of Mathematics, University of Bristol, University Walk, Bristol BS8 1TH (United Kingdom); Popescu, Sandu [HH Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Hewlett-Packard Laboratories, Stoke Gifford, Bristol BS12 6QZ (United Kingdom)

2005-12-15T23:59:59.000Z

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


201

NREL: Concentrating Solar Power Research - Publications  

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

Publications Publications NREL develops publications, including technical reports and papers, about its R&D activities in concentrating solar power, as well as related information. Below you'll find a list of selected NREL publications concerning these activities. Also see TroughNet's publications on parabolic trough technology, and market and economic assessment. For other NREL concentrating solar power publications, you can search NREL's Publications Database. Selected Publications These publications are available as Adobe Acrobat PDFs. Utility-Scale Power Tower Solar Systems: Performance Acceptance Test Guidelines NREL Subcontract Report Author: David Kearney - Kearney & Associates Publication Date: March 2013 Simulating the Value of Concentrating Solar Power with Thermal Energy

202

Concentric ring flywheel without expansion separators  

DOE Patents (OSTI)

A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion.

Kuklo, Thomas C. (Oakdale, CA)

1999-01-01T23:59:59.000Z

203

Concentric ring flywheel without expansion separators  

DOE Patents (OSTI)

A concentric ring flywheel wherein the adjacent rings are configured to eliminate the need for differential expansion separators between the adjacent rings. This is accomplished by forming a circumferential step on an outer surface of an inner concentric ring and forming a matching circumferential step on the inner surface of an adjacent outer concentric ring. During operation the circumferential steps allow the rings to differentially expand due to the difference in the radius of the rings without the formation of gaps therebetween, thereby eliminating the need for expansion separators to take up the gaps formed by differential expansion. 3 figs.

Kuklo, T.C.

1999-08-24T23:59:59.000Z

204

VSHOT Measurements of Distal II Dish Concentrators  

DOE Green Energy (OSTI)

The Video Scanning Hartmann Optical Tester (VSHOT) is a laser ray-trace tool for measuring the slope error of solar concentrator mirrors. The VSHOT measurements made on two, 8.5-m diameter, Distal II dishes represent its first use on a concentrator installed and operating in the field. A number of valuable lessons were learned regarding the use of the VSHOT for outdoor testing. The two dishes were found to have overall figure-of-merit RMS slope errors from an ideal parabola of 2.99 and 3.18 milliradians. The VSHOT measurements compare well qualitatively with distant observer photographs made using a colored concentric ring target.

Jones, S.A.

1998-12-14T23:59:59.000Z

205

International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen: Book of Abstracts  

DOE Green Energy (OSTI)

The International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen provides an opportunity to learn about current significant research on solar concentrators for generating electricity or hydrogen. The conference will emphasize in-depth technical discussions of recent achievements in technologies that convert concentrated solar radiation to electricity or hydrogen, with primary emphasis on photovoltaic (PV) technologies. Very high-efficiency solar cells--above 37%--were recently developed, and are now widely used for powering satellites. This development demands that we take a fresh look at the potential of solar concentrators for generating low-cost electricity or hydrogen. Solar electric concentrators could dramatically overtake other PV technologies in the electric utility marketplace because of the low capital cost of concentrator manufacturing facilities and the larger module size of concentrators. Concentrating solar energy also has advantages for th e solar generation of hydrogen. Around the world, researchers and engineers are developing solar concentrator technologies for entry into the electricity generation market and several have explored the use of concentrators for hydrogen production. The last conference on the subject of solar electric concentrators was held in November of 2003 and proved to be an important opportunity for researchers and developers to share new and crucial information that is helping to stimulate projects in their countries.

McConnell, R.; Symko-Davies, M.; Hayden, H.

2005-05-01T23:59:59.000Z

206

NREL: Concentrating Solar Power Research - Particle Receiver...  

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

Bed-Novel Components to Overcome Existing Barriers Advancing concentrating solar power (CSP) systems to the target cost of 0.06 per kilowatt-hour, set by the U.S. Department of...

207

Analytical Solutions for Cloud-Drop Concentration  

Science Conference Proceedings (OSTI)

This note compares and evaluates the analytical solutions of Squires and Twomey for cloud droplet concentration. Either solution is likely to be fairly accurate (±30%) when the slope parameter (?) of the cloud condensation nuclei distribution is ...

David B. Johnson

1981-01-01T23:59:59.000Z

208

Linear Concentrator Systems | Open Energy Information  

Open Energy Info (EERE)

Linear Concentrator Systems Linear Concentrator Systems Jump to: navigation, search Introduction Linear concentrating collector fields consist of a large number of collectors in parallel rows that are typically aligned in a north-south orientation to maximize both annual and summertime energy collection. With a single-axis sun-tracking system, this configuration enables the mirrors to track the sun from east to west during the day, ensuring that the sun reflects continuously onto the receiver tubes. Parabolic Trough Systems The predominant CSP systems currently in operation in the United States are linear concentrators using parabolic trough collectors. In such a system, the receiver tube is positioned along the focal line of each parabola-shaped reflector. The tube is fixed to the mirror structure and

209

Concentrating solar power | Open Energy Information  

Open Energy Info (EERE)

Concentrating Solar Power Basics (The following text is derived from NREL's concentrating solar power information page.)[1] Concentrating solar power (CSP) offers a utility-scale, firm, dispatchable renewable energy option that can help meet our nation's demand for electricity. CSP plants produce power by first using mirrors to focus sunlight to heat a working fluid. Ultimately, this high-temperature fluid is used to spin a turbine or power an engine that drives a generator. And the final product is electricity. Smaller CSP systems can be located directly where the power is needed. Larger, utility-scale CSP applications provide hundreds of megawatts of electricity for the power grid. Both linear concentrator and power tower systems can be easily integrated with thermal storage, helping to generate

210

Power Tower Systems for Concentrating Solar Power  

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

In power tower concentrating solar power systems, numerous large, flat, sun-tracking mirrors, known as heliostats, focus sunlight onto a receiver at the top of a tall tower. A heat-transfer fluid...

211

What does stabilizing greenhouse gas concentrations mean?  

E-Print Network (OSTI)

The MIT Emissions Prediction and Policy Analysis (EPPA) model is applied to an exploration of the national emissions obligations that would be required to stabilize atmospheric CO2 concentrations at levels now under active ...

Jacoby, Henry D.; Schmalensee, Richard.; Reiner, David M.

212

Concentrating Solar Power Commercial Application Study  

E-Print Network (OSTI)

Concentrating Solar Power Technologies............................................... 7 Parabolic Troughs power technologies are described in this report: parabolic troughs, linear Fresnel, power towers, and dish/engine. Parabolic troughs are the most commercially available technology. Linear Fresnel and power

Laughlin, Robert B.

213

Biological denitrification of high concentration nitrate waste  

DOE Patents (OSTI)

Biological denitrification of nitrate solutions at concentrations of greater than one kilogram nitrate per cubic meter is accomplished anaerobically in an upflow column having as a packing material a support for denitrifying bacteria.

Francis, Chester W. (Oak Ridge, TN); Brinkley, Frank S. (Knoxville, TN)

1977-01-01T23:59:59.000Z

214

NREL: Learning - Concentrating Solar Power Basics  

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

Concentrating Solar Power Basics Many power plants today use fossil fuels as a heat source to boil water. The steam from the boiling water spins a large turbine, which drives a...

215

NREL: Concentrating Solar Power Research - Research Staff  

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

Research Staff Here you'll find contact information for NREL's concentrating solar power research team and staff. To learn more about us and our expertise, read the staff's...

216

Test results of early photovoltaic concentrating collectors  

SciTech Connect

Several passively and actively cooled photovoltaic concentrating collectors built during the period 1976 to 1979 have been tested. The tests provide information on the performance characteristics of these collectors. The results of the tests are summarized.

Gerwin, H.J.; Pritchard, D.A.

1981-11-01T23:59:59.000Z

217

Spectral converters and luminescent solar concentrators  

E-Print Network (OSTI)

In this paper we present a comprehensive theoretical description of molecular spectral converters in the specific context of Luminescent Solar Concentrators (LSCs). The theoretical model is an extension to a three-level system interacting with a solar radiation bath of the standard quantum theory of atomic radiative processes. We derive the equilibrium equations of the conversion process and provide specific examples of application of this principle to the development of solar concentration devices.

Petra F. Scudo; Luigi Abbondanza; Roberto Fusco

2009-07-21T23:59:59.000Z

218

Spectral converters and luminescent solar concentrators  

E-Print Network (OSTI)

In this paper we present a comprehensive theoretical description of molecular spectral converters in the specific context of Luminescent Solar Concentrators (LSCs). The theoretical model is an extension to a three-level system interacting with a solar radiation bath of the standard quantum theory of atomic radiative processes. We derive the equilibrium equations of the conversion process and provide specific examples of application of this principle to the development of solar concentration devices.

Scudo, Petra F; Fusco, Roberto

2009-01-01T23:59:59.000Z

219

Georgia Tech spiral concentrator: an innovative design  

Science Conference Proceedings (OSTI)

A new, low cost, high performance solar energy concentrator has been developed at Georgia Tech. It is based on Fresnel reflector principles, and is formed by slightly winding a flat spiral of reflective material and securing it to a planar frame. Special focal distributions are easily designed into the concentrator. A wide variety of applications exist for this new device, ranging from generation of industrial process heat to solar cooking.

Steenblik, R.A.; Bomar, S.H. Jr.

1981-01-01T23:59:59.000Z

220

NREL: Concentrating Solar Power Research Home Page  

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

A collage of Concentrating Solar Power photographs. The first photo shows a dish-engine solar system. The second is of a SAIC Stirling dish collector. And the third photo shows a SkyTrough solar concentrator located on a mesa top. A collage of Concentrating Solar Power photographs. The first photo shows a dish-engine solar system. The second is of a SAIC Stirling dish collector. And the third photo shows a SkyTrough solar concentrator located on a mesa top. NREL collaborates with industry to further the research and development (R&D) of concentrating solar power (CSP) plant and solar thermal technologies. NREL's projects in concentrating solar power focus on components R&D and systems analysis related to power tower and parabolic trough technologies: Collectors Receivers Power block Thermal energy storage Analysis. In addition, NREL has received funding through the following competitively awarded projects: 10-megawatt supercritical carbon dioxide (s-CO2) turbine test Near-blackbody, enclosed-particle receiver integrated with a

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


221

Energy Basics: Dish/Engine Systems for Concentrating Solar Power  

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

power plant. Solar Concentrator The solar concentrator, or dish, gathers the solar energy coming directly from the sun. The resulting beam of concentrated sunlight is reflected...

222

Efficient Solar Concentrators: Affordable Energy from Water and Sunlight  

Science Conference Proceedings (OSTI)

Broad Funding Opportunity Announcement Project: Teledyne is developing a liquid prism panel that tracks the position of the sun to help efficiently concentrate its light onto a solar cell to produce power. Typically, solar tracking devices have bulky and expensive mechanical moving parts that require a lot of power and are often unreliable. Teledyne’s liquid prism panel has no bulky and heavy supporting parts—instead it relies on electrowetting. Electrowetting is a process where an electric field is applied to the liquid to control the angle at which it meets the sunlight above and to control the angle of the sunlight to the focusing lensthe more direct the angle to the focusing lens, the more efficiently the light can be concentrated to solar panels and converted into electricity. This allows the prism to be tuned like a radio to track the sun across the sky and steer sunlight into the solar cell without any moving mechanical parts. This process uses very little power and requires no expensive supporting hardware or moving parts, enabling efficient and quiet rooftop operation for integration into buildings.

None

2010-01-01T23:59:59.000Z

223

Development Efforts on Silicon Solar Cells  

Science Conference Proceedings (OSTI)

A stable, high-efficiency photovoltaic cell technology was developed for use in advanced systems that generate electricity from highly concentrated sunlight.

1992-02-01T23:59:59.000Z

224

Concentration of perrhenate and pertechnetate solutions  

DOE Green Energy (OSTI)

A method of preparing a concentrated solution of a carrier-free radioisotope which includes the steps of: a. providing a generator column loaded with a composition containing a parent radioisotope; b. eluting the generator column with an eluent solution which includes a salt of a weak acid to elute a target daughter radioisotope from the generator column in a first eluate. c. eluting a cation-exchange column with the first eluate to exchange cations of the salt for hydrogen ions and to elute the target daughter radioisotope and a weak acid in a second eluate; d. eluting an anion-exchange column with the second eluate to trap and concentrate the target daughter radioisotope and to elute the weak acid solution therefrom; and e. eluting the concentrated target daughter radioisotope from the anion-exchange column with a saline solution.

Knapp, Furn F. (Oak Ridge, TN); Beets, Arnold L. (Clinton, TN); Mirzadeh, Saed (Knoxville, TN); Guhlke, Stefan (Bonn, DE)

1998-01-01T23:59:59.000Z

225

Low-Cost, Lightweight Solar Concentrators  

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

Concentrators Concentrators California Institute of Technology/Jet Propulsion Laboratory Award Number:0595-1612 | April 18, 2013 | Ganapathi * Mirror module development has been approached with the goal of being applicable to all types of CSP systems * Several heliostat design options being considered to address driving requirements: * Facets that are compliant to winds > 35 mph * Deep structures for optimizing structural efficiency * Pointing accuracy achieved with mechanism design * Simple precision components * Easy on-site assembly with pre-fab components * Structural foam properties and strengthening trades being conducted to reduce overall costs with FEM models Goal: Typical costs for a concentrator (heliostat or parabolic dish) can range between 40-50% of the total costs. To meet SunShot

226

concentrating solar power | OpenEI  

Open Energy Info (EERE)

concentrating solar power concentrating solar power Dataset Summary Description This dataset is part of a larger internal dataset at the National Renewable Energy Laboratory (NREL) that explores various characteristics of large solar electric (both PV and CSP) facilities around the United States. This dataset focuses on the land use characteristics for solar facilities that are either under construction or currently in operation. Source Land-Use Requirements for Solar Power Plants in the United States Date Released June 25th, 2013 (7 months ago) Date Updated Unknown Keywords acres area average concentrating solar power csp Density electric hectares km2 land land requirements land use land-use mean photovoltaic photovoltaics PV solar statistics Data application/vnd.openxmlformats-officedocument.spreadsheetml.sheet icon Master Solar Land Use Spreadsheet (xlsx, 1.5 MiB)

227

Spectroscopic detection of nitrogen concentrations in sagebrush  

SciTech Connect

The ability to estimate foliar nitrogen (N) in semi-arid landscapes can yield information on nutritional status and improve our limited understanding of controls on canopy photosynthesis. We examined two spectroscopic methods for estimating sagebrush dried leaf and live shrub N content: first derivative reflectance (FDR) and continuum removal. Both methods used partial least squares (PLS) regression to select wavebands most significantly correlated with N concentrations in the samples. Sagebrush dried leaf spectra produced PLS models (R2 = 0.76–0.86) that could predict N concentrations within the dataset more accurately than PLS models generated from live shrub spectra (R2 = 0.41–0.63). Inclusion of wavelengths associated with leaf water in the FDR transformations appeared to improve regression results. Findings are encouraging and warrant further exploration into sagebrush reflectance spectra to characterize N concentrations.

J. J. MITCHELL; N. F. GLENN; T.T. SANKEY; D. R. DERRYBERRY; R. C. HRUSKA; M. O. Anderson

2012-07-01T23:59:59.000Z

228

Concentration and purification of plutonium or thorium  

DOE Patents (OSTI)

In this invention a first solution obtained from such as a plutonium/thorium purification process or the like, containing plutonium (Pu) and/or thorium (Th) in such as a low nitric acid (HNO.sub.3) concentration may have the Pu and/or Th separated and concentrated by passing an electrical current from a first solution having disposed therein an anode to a second solution having disposed therein a cathode and separated from the first solution by a cation permeable membrane, the Pu or Th cation permeating the cation membrane and forming an anionic complex within the second solution, and electrical current passage affecting the complex formed to permeate an anion membrane separating the second solution from an adjoining third solution containing disposed therein an anode, thereby effecting separation and concentration of the Pu and/or Th in the third solution.

Hayden, John A. (Arvada, CO); Plock, Carl E. (Golden, CO)

1976-01-01T23:59:59.000Z

229

Design package for concentrating solar collector panels  

DOE Green Energy (OSTI)

Information used to evaluate the design of the Northrup concentrating collector is presented. Included are the system performance specifications, the applications manual, and the detailed design drawings of the collector. The Northrup concentrating solar collector is a water/glycol/working fluid type, dipped galvanized steel housing, transparent acrylic Fresnel lens cover, copper absorber tube, fiber glass insulation and weighs 98 pounds. The gross collector area is about 29.4/sup 2/ per collector. A collector assembly includes four collector units within a tracking mount array.

Not Available

1978-08-01T23:59:59.000Z

230

Installation package for concentrating solar collector panels  

DOE Green Energy (OSTI)

Northrup, Inc., has developed and delivered 300 square feet of Concentrating Solar Collector (ML Series) and Attitude Control System, under the direction of the National Aeronautics and Space Administration. The ''ML Series'' Solar Collector Panels comprise a complete package array consisting of collector panels using modified Fresnel Prismatic Lenses for a 10 to 1 concentrating ration, supporting framework, fluid manifolding and tracking drive system, in unassembled components for field erection. The Installation, Operation and Maintenance Manual, Warranty, List of Materials, Sub-Assembly drawings and Final Field Assembly Drawings are included in the package.

Not Available

1978-08-01T23:59:59.000Z

231

Characterization of Chronic Enteropathies in Dogs by Use of Fecal and Urinary N-methylhistamine Concentrations and Serum Methylmalonic Acid Concentrations  

E-Print Network (OSTI)

Non-invasive markers that are clinically useful for the diagnosis and monitoring of canine chronic enteropathies are scarce. The first aim of this study was to investigate the prevalence of cobalamin deficiency on a cellular level in dogs with chronic gastrointestinal disease by measuring serum methylmalonic acid (MMA) concentrations. Hypocobalaminemia has been associated with a negative outcome in dogs with chronic enteropathies, but the prevalence of cellular cobalamin deficiency is unknown. The second aim of this study was to determine the utility of fecal and urinary concentrations of N-methylhistamine (NMH) as a marker of gastrointestinal inflammation and disease activity in dogs with chronic enteropathies. Serum MMA concentrations were measured in healthy control dogs to establish a reference interval, which was calculated to be 415-1,193 nmol/L. Measurement of MMA concentrations in 555 serum samples from dogs with varying cobalamin concentrations showed a significant increase (p<0.05) in dogs with hypocobalaminemia. In a prospective group of 56 dogs with chronic enteropathies, 36% had decreased serum cobalamin concentrations, five of which (9% of 56 dogs) had increased serum MMA concentrations. We conclude that hypocobalaminemia is commonly seen in dogs with chronic gastrointestinal disease, but does not always appear to be associated with cellular cobalamin deficiency. In 47 dogs with chronic enteropathies, fecal and urinary NMH concentrations were increased in 21% and 27%, respectively, indicating that mast cell degranulation plays a role in a subset of dogs with chronic enteropathies. However fecal and urinary NMH concentrations did not correlate with each other, or with the clinical activity index. Urinary NMH concentrations correlated significantly with serum CRP concentrations, and were also significantly associated with severity of duodenal mucosal inflammation (p=0.008). The lack of correlation with the clinical activity index suggests that degranulation of mast cells only plays a role in some dogs with chronic enteropathies. Also, these results suggest that NMH alone may not be a good marker for clinical disease activity in dogs with chronic enteropathies. Due to its linear association with serum CRP and severity of mucosal inflammation, urinary NMH concentrations may be a better marker of intestinal inflammation than fecal NMH concentrations.

Berghoff, Nora

2012-08-01T23:59:59.000Z

232

GaInNAs Junctions for Next-Generation Concentrators: Progress and Prospects  

DOE Green Energy (OSTI)

We discuss progress in the development of GaInNAs junctions for application in next-generation multijunction concentrator cells. A significant development is the demonstration of near-100% internal quantum efficiencies in junctions grown by molecular-beam epitaxy. Testing at high currents validates the compatibility of these devices with concentrator operation. The efficiencies of several next-generation multijunction structures incorporating these state-of-the-art GaInNAs junctions are projected.

Friedman, D. J.; Ptak, A. J.; Kurtz, S. R.; Geisz, J. F.; Kiehl, J.

2005-08-01T23:59:59.000Z

233

Performance and Reliability of Multijunction III-V Modules for Concentrator Dish and Central Receiver Applications  

Science Conference Proceedings (OSTI)

Over the last 15 years, Solar Systems have developed a dense array receiver PV technology for 500X concentrator reflective dish applications. This concentrator PV technology has been successfully deployed at six different locations in Australia, counting for more than 1 MWp of installed peak power. A new Multijunction III-V receiver to replace the current silicon Point-Contact solar cells has recently been developed. The new receiver technology is based on high-efficiency (>32%) Concentrator Ultra Triple Junction (CUTJ) solar cells from Spectrolab, resulting in system power and energy performance improvement of more than 50% compared to the silicon cells. The 0.235 m{sup 2} concentrator PV receiver, designed for continuous 500X operation, is composed of 64 dense array modules, and made of series and parallel-connected solar cells, totaling approximately 1,500 cells. The individual dense array modules have been tested under high intensity pulsed light, as well as with concentrated sunlight at the Solar Systems research facility and at the National Renewable Energy Laboratory's High Flux Solar Furnace. The efficiency of the dense array modules ranges from 30% to 36% at 500X (50 W/cm{sup 2}, AM1.5D low AOD, 21C). The temperature coefficients for power, voltage and current, as well as the influence of Air Mass on the cell responsivity, were measured. The reliability of the dense array multijunction III-V modules has been studied with accelerated aging tests, such as thermal cycling, damp heat and high-temperature soak, and with real-life high-intensity exposure. The first 33 kWp multijunction III-V receiver was recently installed in a Solar Systems dish and tested in real-life 500X concentrated sunlight conditions. Receiver efficiencies of 30.3% and 29.0% were measured at Standard Operating Conditions and Normal Operating Conditions respectively.

Verlinden, P. J.; Lewandowski, A.; Bingham, C.; Kinsey, G. S.; Sherif, R. A.; Laisch, J. B.

2006-01-01T23:59:59.000Z

234

Low-Cost Installation of Concentrating Photovoltaic  

E-Print Network (OSTI)

Low-Cost Installation of Concentrating Photovoltaic Renewable Energy Research Renewable Energy Research http://www.energy.ca.gov/research/renewabl e/index.html August 2011 The Issue Several factors inhibit the potential growth of the California photovoltaic market: high installation costs, expenses

235

SunShot Initiative: Concentrating Solar Power  

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

Power Power SunShot CSP Team Learn more about the SunShot concentrating solar power program staff by visiting the team's profile pages. Argonne National Laboratory Argonne National Laboratory High-Efficiency Thermal Energy Storage System for CSP University of California Los Angeles University of California Los Angeles High Operating Temperature Liquid Metal Heat Transfer Fluids Jet Propulsion Laborator Jet Propulsion Laboratory Low-Cost, Lightweight Solar Concentrators Abengoa Solar Abengoa Solar Advanced Nitrate Salt Central Receiver Power Plant HiTek Services HiTek Services Low-Cost Heliostat Development The Department of Energy (DOE) supports research and development of concentrating solar power (CSP) technologies as a unique path to achieve SunShot Initiative cost targets with systems that can supply solar power on demand through the use of thermal storage. CSP technologies use mirrors to reflect and concentrate sunlight onto receivers that collect solar energy and convert it to heat. Thermal energy can then be used to produce electricity via a turbine or heat engine driving a generator.

236

Low chemical concentrating steam generating cycle  

DOE Patents (OSTI)

A steam cycle for a nuclear power plant having two optional modes of operation. A once-through mode of operation uses direct feed of coolant water to an evaporator avoiding excessive chemical concentration buildup. A recirculation mode of operation uses a recirculation loop to direct a portion of flow from the evaporator back through the evaporator to effectively increase evaporator flow.

Mangus, James D. (Greensburg, PA)

1983-01-01T23:59:59.000Z

237

Western North Pacific Typhoons with Concentric Eyewalls  

Science Conference Proceedings (OSTI)

This study examines the intensity change and moat dynamics of typhoons with concentric eyewalls using passive microwave data and best-track data in the western North Pacific between 1997 and 2006. Of the 225 typhoons examined, 55 typhoons and 62 ...

Hung-Chi Kuo; Chih-Pei Chang; Yi-Ting Yang; Hau-Jang Jiang

2009-11-01T23:59:59.000Z

238

HELIOS: a computational model for solar concentrators  

DOE Green Energy (OSTI)

HELIOS is a computer code for mathematically simulating the behavior of the flux pattern from the concentrator field for a solar central receiver power station. Statistical methods are used to incorporate nondeterministic factors. The code is described, and some examples of its output are given.

Biggs, F.; Vittitoe, C.N.

1977-01-01T23:59:59.000Z

239

Thermal Management of Solar Cells  

E-Print Network (OSTI)

as a source of photovoltaic energy is rapidly increasingphotovoltaic cells under concentrated illumination: a critical review," Solar Energyphotovoltaic/thermal collector, PV/T, and it utilizes both electrical and heat energies

Saadah, Mohammed Ahmed

2013-01-01T23:59:59.000Z

240

Cell Data Sheet Specification (Presentation)  

DOE Green Energy (OSTI)

The presentation shows a brief status report on the development of a specification being considered by IEC TC82 WG7 for a concentrator cell data sheet and solicits suggestions from the community.

Kurtz, S.

2012-03-01T23:59:59.000Z

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


241

Low-Cost, Lightweight Solar Concentrators  

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

Concentrators Concentrators California Institute of Technology/Jet Propulsion Laboratory Award Number:0595-1612 | January 15, 2013 | Ganapathi Thin Film mirror is ~40-50% cheaper and 60% lighter than SOA * Project leverages extensive space experience by JPL and L'Garde to develop a low-cost parabolic dish capable of providing 4 kW thermal. Key features: * Metallized reflective thin film material with high reflectivity (>93%) with polyurethane foam backing * Single mold polyurethane backing fabrication enables low cost high production manufacturing * Ease of panel installation and removal enables repairs and results in a low total life cycle cost * Deployment of multiple dishes enhances system level optimizations by simulating larger fields which addresses issues like shared resources

242

NREL: Concentrating Solar Power Research - Partnerships  

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

Partnerships Partnerships NREL maintains partnerships to advance concentrating solar power research, development, and deployment efforts. Currently, NREL works with Sandia National Laboratories in Albuquerque, New Mexico, through SunLab-a partnership developed by the U.S. Department of Energy to administer its concentrating solar power R&D and analysis activities. SolarPACES Solar Power and Chemical Energy Systems (SolarPACES), an international program of the International Energy Agency, furthers collaborative development, testing, and marketing of CSP plants. NREL represents the U.S. activities and serves on various committees in SolarPACES, which now has 13 members: Algeria, Australia, Egypt, the European Commission, France, Germany, Israel, Mexico, South Africa, South Korea, Spain, Switzerland, and

243

NREL: Concentrating Solar Power Research - Laboratory Capabilities  

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

Laboratory Capabilities Laboratory Capabilities To research, develop, and test a variety of concentrating solar power technologies, NREL features the following laboratory capabilities: High-Flux Solar Furnace (HFSF) Large Payload Solar Tracker Advanced Optical Materials Laboratory Advanced Thermal Storage Materials Laboratory Optical Testing Laboratory and Beam Characterization System Receiver Test Laboratory Heat Collection Element (HCE) Temperature Survey Photo of NREL's High-Flux Solar Furnace. NREL's High-Flux Solar Furnace. High-Flux Solar Furnace (HFSF) The power generated at NREL's High-Flux Solar Furnace (HFSF) can be used to expose, test, and evaluate many components-such as receivers, collectors, and reflector materials-used in concentrating solar power systems. The 10-kilowatt HFSF consists of a tracking heliostat and 25 hexagonal

244

Concentrating Solar Power: Energy from Mirrors  

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

Mirror mirror on the wall, what's the Mirror mirror on the wall, what's the greatest energy source of all? The sun. Enough energy from the sun falls on the Earth everyday to power our homes and businesses for almost 30 years. Yet we've only just begun to tap its potential. You may have heard about solar electric power to light homes or solar thermal power used to heat water, but did you know there is such a thing as solar thermal-electric power? Electric utility companies are using mirrors to concentrate heat from the sun to produce environmentally friendly electricity for cities, especially in the southwestern United States. The southwestern United States is focus- ing on concentrating solar energy because it's one of the world's best areas for sun- light. The Southwest receives up to twice the sunlight as other regions in the coun-

245

NREL: Concentrating Solar Power Research - Projects  

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

Projects Projects NREL's concentrating solar power (CSP) projects focus on components R&D and systems analysis related to power tower and parabolic trough technologies. We support the U.S. Department of Energy (DOE) in its CSP deployment efforts in the following areas: Collectors Receivers Power block Thermal energy storage Analysis. NREL received funding from DOE for concentrating solar power research projects. Through a competitive process, NREL was selected to lead the following projects: Novel Components to Overcome Existing Barriers-Particle Receiver Integrated with a Fluidized Bed Thermodynamic Cycle to Revolutionize CSP Systems-10-Megawatt Supercritical Carbon Dioxide (s-CO2) Turbine Test Nanomaterials for thermal energy storage in CSP plants In addition to these efforts, NREL is also a key partner on two other

246

ORIGINAL ARTICLE Radionuclide Concentrations in Benthic Invertebrates  

Office of Legacy Management (LM)

Environ Monit Assess (2007) 128:329-341 Environ Monit Assess (2007) 128:329-341 DO1 10.1007/~10661-006-93 I 6 4 ORIGINAL ARTICLE - Radionuclide Concentrations in Benthic Invertebrates from Amchitka and Kiska Islands in the Aleutian Chain, Alaska Joanna Burger Michael Gochfeld Stephen C. Jewett Received: 8 March 2006 /Accepted: 8 May 2006 1 Published online: 21 October 2006 0 Springer Science + Business Media B.V. 2006 Abstract Concentrations of 13 radionuclides 1291, 60co, 1 5 2 ~ ~ , 9 0 s r , 9 9 ~ ~ , 2 4 1 ~ ~ , 238pu, 239249pu, 2 3 4 ~ , 2 3 5 ~ , 236U, 2 3 8 ~ were examined in seven species of invertebrates from Amchitka and Kiska Islands, in the Aleutian Chain of Alaska, using gamma spectroscopy, inductively coupled plasma mass spectroscopy, and alpha spectroscopy. Amchitka Island was the site of three underground nuclear test

247

CAST STONE FORMULATION AT HIGHER SODIUM CONCENTRATIONS  

SciTech Connect

A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited

Fox, K.; Edwards, T.; Roberts, K.

2013-10-02T23:59:59.000Z

248

CAST STONE FORMULATION AT HIGHER SODIUM CONCENTRATIONS  

SciTech Connect

A low temperature waste form known as Cast Stone is being considered to provide supplemental Low Activity Waste (LAW) immobilization capacity for the Hanford site. Formulation of Cast Stone at high sodium concentrations is of interest since a significant reduction in the necessary volume of Cast Stone and subsequent disposal costs could be achieved if an acceptable waste form can be produced with a high sodium molarity salt solution combined with a high water to premix (or dry blend) ratio. The objectives of this study were to evaluate the factors involved with increasing the sodium concentration in Cast Stone, including production and performance properties and the retention and release of specific components of interest. Three factors were identified for the experimental matrix: the concentration of sodium in the simulated salt solution, the water to premix ratio, and the blast furnace slag portion of the premix. The salt solution simulants used in this study were formulated to represent the overall average waste composition. The cement, blast furnace slag, and fly ash were sourced from a supplier in the Hanford area in order to be representative. The test mixes were prepared in the laboratory and fresh properties were measured. Fresh density increased with increasing sodium molarity and with decreasing water to premix ratio, as expected given the individual densities of these components. Rheology measurements showed that all of the test mixes produced very fluid slurries. The fresh density and rheology data are of potential value in designing a future Cast Stone production facility. Standing water and density gradient testing showed that settling is not of particular concern for the high sodium compositions studied. Heat of hydration measurements may provide some insight into the reactions that occur within the test mixes, which may in turn be related to the properties and performance of the waste form. These measurements showed that increased sodium concentration in the salt solution reduced the time to peak heat flow, and reducing the amount of slag in the premix increased the time to peak heat flow. These observations may help to describe some of the cured properties of the samples, in particular the differences in compressive strength observed after 28 and 90 days of curing. Samples were cured for at least 28 days at ambient temperature in the laboratory prior to cured properties analyses. The low activity waste form for disposal at the Hanford Site is required to have a compressive strength of at least 500 psi. After 28 days of curing, several of the test mixes had mean compressive strengths that were below the 500 psi requirement. Higher sodium concentrations and higher water to premix ratios led to reduced compressive strength. Higher fly ash concentrations decreased the compressive strength after 28 days of curing. This may be explained in that the cementitious phases matured more quickly in the mixes with higher concentrations of slag, as evidenced by the data for the time to peak heat generation. All of the test mixes exhibited higher mean compressive strengths after 90 days of curing, with only one composition having a mean compressive strength of less than 500 psi. Leach indices were determined for the test mixes for contaminants of interest. The leaching performance of the mixes evaluated in this study was not particularly sensitive to the factors used in the experimental design. This may be beneficial in demonstrating that the performance of the waste form is robust with respect to changes in the mix composition. The results of this study demonstrate the potential to achieve significantly higher waste loadings in Cast Stone and other low temperature, cementitious waste forms. Additional work is needed to elucidate the hydration mechanisms occurring in Cast Stone formulated with highly concentrated salt solutions since these reactions are responsible for determining the performance of the cured waste form. The thermal analyses completed in this study provide some preliminary insight, although the limited

Fox, K.; Roberts, K.; Edwards, T.

2013-09-17T23:59:59.000Z

249

Solar concentrator with restricted exit angles  

DOE Patents (OSTI)

A device is provided for the collection and concentration of radiant energy and includes at least one reflective side wall. The wall directs incident radiant energy to the exit aperture thereof or onto the surface of energy absorber positioned at the exit aperture so that the angle of incidence of radiant energy at the exit aperture or on the surface of the energy absorber is restricted to desired values.

Rabl, Arnulf (Downers Grove, IL); Winston, Roland (Chicago, IL)

1978-12-19T23:59:59.000Z

250

CONCENTRATION OF CESIUM-137 BY ALGAE  

SciTech Connect

The adsorption-absorption of Cs/sup 137/ by algae is of interest because Cs/sup 137/ of the critical fission products in power reactor wastes and atomic weapon fall-out. It is well known that plankton takes up radioactivity in fairly high concentrations. The purpose of this investigation was to study the accumulation of Cs/sup 137/ by fresh water-algae. (A.C.)

Williams, L.G.; Swanson, H.D.

1958-01-24T23:59:59.000Z

251

Efficiency of luminescence in luminescent solar concentrators  

Science Conference Proceedings (OSTI)

The power effiency of luminescence excited by solar radiation in luminescent solar collectors is calculated for a glass sheet doped with CR/sup 3 +/. The achievable chemical potential for an optically thick absorber irradiated by diluted blackbody radiation as a function of Cr/sup 3 +/ concentration, sheet thickness, sunlight dilution, and luminescence quantum yield leads directly to overall conversion efficiency of solar power to luminescence power.

Lempicki, A.

1983-04-15T23:59:59.000Z

252

Material for a luminescent solar concentrator  

DOE Patents (OSTI)

A material for use in a luminescent solar concentrator, formed by ceramitizing the luminescent ion Cr/sup 3 +/ with a transparent ceramic glass containing mullite. The resultant material has tiny Cr/sup 3 +/-bearing crystallites dispersed uniformly through an amorphous glass. The invention combines the high luminescent efficiency of Cr/sup 3 +/ in the crystalline phase with the practical and economical advantages of glass technology.

Andrews, L.J.

1984-01-01T23:59:59.000Z

253

Paper: Safeguards design for a plutonium concentrator  

Science Conference Proceedings (OSTI)

In this paper we consider the design of a nonlinear estimator to be used in conjunction with on-line detectors for a plutonium nitrate concentrator. Using a complex state-of-the-art process model to simulate 'realistic' data, we show that the estimator ... Keywords: (diversion detection), (nuclear safeguards), Kalman filter, decision theory, nonlinear filtering, nuclear plants, on-line operation, optimal filtering, state estimation

J. V. Candy; R. B. Rozsa

1980-11-01T23:59:59.000Z

254

Development of a prototype lignin concentration sensor  

DOE Green Energy (OSTI)

The US Department of Energy, Office of Industrial Technologies, is sponsoring a research and development program for the development of a real-time, in-situ sensor to measure the concentration of lignin in wood pulp. The program is composed of phase I showing feasibility which is now complete, phase II for development and testing of a Field Prototype, in progress, Phase III commercialization. Phase I work (funded entirely by B&W) demonstrated a correlation between the fluorescence intensity and lignin concentration (as measured by TAPPI procedure, T 236 hm-85 Kappa Number of Pulp) for undiluted wood pulp samples. In Phase II, a laboratory test program directed at characterizing the fluorescence of wood pulp has been conducted as a prelude to the design of a prototype sensor. The current report summarizes the testing completed in Phase I and documents the Phase II laboratory testing completed through December 1991. Future Phase II efforts include additional laboratory testing, design and fabrication of a prototype sensor, and field testing of the prototype sensor. Phase III of the program will concentrate on the incorporation of the sensor into a control system and commercialization of the sensor.

Malito, M.L.; Jeffers, L.A.

1993-01-01T23:59:59.000Z

255

Development of a prototype lignin concentration sensor  

DOE Green Energy (OSTI)

The US Department of Energy, Office of Industrial Technologies, is sponsoring a research and development program for the development of a real-time, in-situ sensor to measure the concentration of lignin in wood pulp. The program is composed of phase I showing feasibility which is now complete, phase II for development and testing of a Field Prototype, in progress, Phase III commercialization. Phase I work (funded entirely by B W) demonstrated a correlation between the fluorescence intensity and lignin concentration (as measured by TAPPI procedure, T 236 hm-85 Kappa Number of Pulp) for undiluted wood pulp samples. In Phase II, a laboratory test program directed at characterizing the fluorescence of wood pulp has been conducted as a prelude to the design of a prototype sensor. The current report summarizes the testing completed in Phase I and documents the Phase II laboratory testing completed through December 1991. Future Phase II efforts include additional laboratory testing, design and fabrication of a prototype sensor, and field testing of the prototype sensor. Phase III of the program will concentrate on the incorporation of the sensor into a control system and commercialization of the sensor.

Malito, M.L.; Jeffers, L.A.

1993-01-01T23:59:59.000Z

256

NREL GIS Data: Continental United States High Resolution Concentrating  

Open Energy Info (EERE)

High Resolution Concentrating High Resolution Concentrating Solar Power Dataset Summary Description Abstract: Monthly and annual average solar resource potential for the lower 48 states of the United States of America. Purpose: Provide information on the solar resource potential for the for the lower 48 states of the United States of America. Supplemental_Information: This data provides monthly average and annual average daily total solar resource averaged over surface cells of approximatley 40 km by 40 km in size. This data was developed from the Climatological Solar Radiation (CSR) Model. The CSR model was developed by the National Renewable Energy Laboratory for the U.S. Department of Energy. Specific information about this model can be found in Maxwell, George and Wilcox (1998) and George and Maxwell (1999). This model uses information on cloud cover, atmostpheric water vapor and trace gases, and the amount of aerosols in the atmosphere to calculate the monthly average daily total insolation (sun and sky) falling on a horizontal surface. The cloud cover data used as input to the CSR model are an 7-year histogram (1985-1991) of monthly average cloud fraction provided for grid cells of approximately 40km x 40km in size. Thus, the spatial resolution of the CSR model output is defined by this database. The data are obtained from the National Climatic Data Center in Ashville, North Carolina, and were developed from the U.S. Air Force Real Time Nephanalysis (RTNEPH) program. Atmospheric water vapor, trace gases, and aerosols are derived from a variety of sources. The procedures for converting the collector at latitude tilt are described in Marion and Wilcox (1994). Where possible, existing ground measurement stations are used to validate the data. Nevertheless, there is uncertainty associated with the meterological input to the model, since some of the input parameters are not avalible at a 40km resolution. As a result, it is believed that the modeled values are accurate to approximately 10% of a true measured value within the grid cell. Due to terrain effects and other micoclimate influences, the local cloud cover can vary significantly even within a single grid cell. Furthermore, the uncertainty of the modeled estimates increase with distance from reliable measurement sources and with the complexity of the terrain.

257

NREL GIS Data: Hawaii Low Resolution Concentrating Solar Power Resource |  

Open Energy Info (EERE)

Low Resolution Concentrating Solar Power Resource Low Resolution Concentrating Solar Power Resource Dataset Summary Description Abstract: Monthly and annual average solar resource potential for Hawaii. Purpose: Provide information on the solar resource potential for Hawaii. The insolation values represent the average solar energy available to a flat plate collector, such as a photovoltaic panel, oriented due south at an angle from horizontal equal to the latitude of the collector location. Supplemental_Information: This data provides monthly average and annual average daily total solar resource averaged over surface cells of approximately 40 km by 40 km in size. This data was developed from the Climatological Solar Radiation (CSR) Model. The CSR model was developed by the National Renewable Energy Laboratory for the U.S. Department of Energy. Specific information about this model can be found in Maxwell, George and Wilcox (1998) and George and Maxwell (1999). This model uses information on cloud cover, atmostpheric water vapor and trace gases, and the amount of aerosols in the atmosphere to calculate the monthly average daily total insolation (sun and sky) falling on a horizontal surface. The cloud cover data used as input to the CSR model are an 7-year histogram (1985-1991) of monthly average cloud fraction provided for grid cells of approximately 40km x 40km in size. Thus, the spatial resolution of the CSR model output is defined by this database. The data are obtained from the National Climatic Data Center in Ashville, North Carolina, and were developed from the U.S. Air Force Real Time Nephanalysis (RTNEPH) program. Atmospheric water vapor, trace gases, and aerosols are derived from a variety of sources. The procedures for converting the collector at latitude tilt are described in Marion and Wilcox (1994). Where possible, existing ground measurement stations are used to validate the data. Nevertheless, there is uncertainty associated with the meterological input to the model, since some of the input parameters are not avalible at a 40km resolution. As a result, it is believed that the modeled values are accurate to approximately 10% of a true measured value within the grid cell. Due to terrain effects and other micoclimate influences, the local cloud cover can vary significantly even within a single grid cell. Furthermore, the uncertainty of the modeled estimates increase with distance from reliable measurement sources and with the complexity of the terrain.

258

NREL GIS Data: Alaska Low Resolution Concentrating Solar Power Resource |  

Open Energy Info (EERE)

Alaska Low Resolution Concentrating Solar Power Resource Alaska Low Resolution Concentrating Solar Power Resource Dataset Summary Description Abstract: Monthly and annual average solar resource potential for Alaska. Purpose: Provide information on the solar resource potential for Alaska. The insolation values represent the average solar energy available to a flat plate collector, such as a photovoltaic panel, oriented due south at an angle from horizontal equal to the latitude of the collector location. Supplemental_Information: This data provides monthly average and annual average daily total solar resource averaged over surface cells of approximatley 40 km by 40 km in size. This data was developed from the Climatological Solar Radiation (CSR) Model. The CSR model was developed by the National Renewable Energy Laboratory for the U.S. Department of Energy. Specific information about this model can be found in Maxwell, George and Wilcox (1998) and George and Maxwell (1999). This model uses information on cloud cover, atmostpheric water vapor and trace gases, and the amount of aerosols in the atmosphere to calculate the monthly average daily total insolation (sun and sky) falling on a horizontal surface. The cloud cover data used as input to the CSR model are an 7-year histogram (1985-1991) of monthly average cloud fraction provided for grid cells of approximately 40km x 40km in size. Thus, the spatial resolution of the CSR model output is defined by this database. The data are obtained from the National Climatic Data Center in Ashville, North Carolina, and were developed from the U.S. Air Force Real Time Nephanalysis (RTNEPH) program. Atmospheric water vapor, trace gases, and aerosols are derived from a variety of sources. The procedures for converting the collector at latitude tilt are described in Marion and Wilcox (1994). Where possible, existing ground measurement stations are used to validate the data. Nevertheless, there is uncertainty associated with the meterological input to the model, since some of the input parameters are not avalible at a 40km resolution. As a result, it is believed that the modeled values are accurate to approximately 10% of a true measured value within the grid cell. Due to terrain effects and other micoclimate influences, the local cloud cover can vary significantly even within a single grid cell. Furthermore, the uncertainty of the modeled estimates increase with distance from reliable measurement sources and with the complexity of the terrain. Units are in watt hours.

259

Series cell light extinction monitor  

DOE Patents (OSTI)

A method and apparatus for using the light extinction measurements from two or more light cells positioned along a gasflow chamber in which the gas volumetric rate is known to determine particle number concentration and mass concentration of an aerosol independent of extinction coefficient and to determine estimates for particle size and mass concentrations. The invention is independent of particle size. This invention has application to measurements made during a severe nuclear reactor fuel damage test.

Novick, Vincent J. (Downers Grove, IL)

1990-01-01T23:59:59.000Z

260

Development of the SEA Corporation Powergrid{trademark} photovoltaic concentrator  

DOE Green Energy (OSTI)

This report covers the three phase effort to bring the SEA Corporation`s Powergrid{trademark} from the concept stage to pilot production. The three phases of this contract covered component development, prototype module development, and pilot line production. The Powergrid is a photovoltaic concentrator that generates direct current electricity directly from sunlight using a linear Fresnel lens. Analysis has shown that the Powergrid has the potential to be very low cost in volume production. Before the start of the project, only proof of concept demonstrations of the components had been completed. During the project, SEA Corporation developed a low cost extruded Fresnel lens, a low cost receiver assembly using one sun type cells, a low cost plastic module housing, a single axis tracking system and frame structure, and pilot production equipment and techniques. In addition, an 800 kW/yr pilot production rate was demonstrated and two 40 kW systems were manufactured and installed.

Kaminar, N.; Curchod, D.; Daroczi, S.; Walpert, M.; Sahagian, J.; Pepper, J. [Photovoltaics International, LLC, Sunnyvale, CA (United States)

1998-03-01T23:59:59.000Z

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


261

SunShot Initiative: National Laboratory Concentrating Solar Power Research  

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

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

262

Pattern recognition monitoring of PEM fuel cell  

DOE Patents (OSTI)

The CO-concentration in the H.sub.2 feed stream to a PEM fuel cell stack is monitored by measuring current and voltage behavior patterns from an auxiliary cell attached to the end of the stack. The auxiliary cell is connected to the same oxygen and hydrogen feed manifolds that supply the stack, and discharges through a constant load. Pattern recognition software compares the current and voltage patterns from the auxiliary cell to current and voltage signature determined from a reference cell similar to the auxiliary cell and operated under controlled conditions over a wide range of CO-concentrations in the H.sub.2 fuel stream.

Meltser, Mark Alexander (Pittsford, NY)

1999-01-01T23:59:59.000Z

263

Pattern recognition monitoring of PEM fuel cell  

DOE Patents (OSTI)

The CO-concentration in the H{sub 2} feed stream to a PEM fuel cell stack is monitored by measuring current and voltage behavior patterns from an auxiliary cell attached to the end of the stack. The auxiliary cell is connected to the same oxygen and hydrogen feed manifolds that supply the stack, and discharges through a constant load. Pattern recognition software compares the current and voltage patterns from the auxiliary cell to current and voltage signature determined from a reference cell similar to the auxiliary cell and operated under controlled conditions over a wide range of CO-concentrations in the H{sub 2} fuel stream. 4 figs.

Meltser, M.A.

1999-08-31T23:59:59.000Z

264

Concentrator Photovoltaic Qualification Standards for Systems Using Refractive and Reflective Optics: Preprint  

DOE Green Energy (OSTI)

This paper describes a proposed international qualification standard for photovoltaic (PV) systems generating electricity from concentrated sunlight. The standard's purpose is to provide stress tests and procedures to identify any component weaknesses in a system. If no weaknesses are identified during qualification, both the manufacturer and the customer can expect a more reliable product. In 2002, we began developing the standard, under the auspices of the International Electrotechnical Commission (IEC), that would describe testing procedures for concentrator PV systems using reflecting (mirrors) or refractive (lenses) optics for focusing sunlight onto solar cells. The initial draft of the IEC standard was based on the first concentrator PV qualification standard published by the Institute of Electrical and Electronics Engineers (IEEE) in the United States in 2001. Well-developed U.S. concentrator technologies use refractive optics, and the IEEE standard needed improvement for testing systems with reflective optics. Furthermore, with record III-V solar cell efficiencies above 37%, concentrator PV developers around the world would like to incorporate such cells into their next generation of technologies. The paper will highlight significant differences between the proposed IEC standard and the earlier IEEE standard.

McConnell, R.; Ji, L.; Lasich, J.; Mansfield, R.

2004-06-01T23:59:59.000Z

265

Experimental studies of the flow of concentrated hard sphere suspensions into a constriction  

E-Print Network (OSTI)

Experimental studies of the flow of concentrated hard sphere suspensions into a constriction L Isa1 driven flow of dense suspensions of micron­ sized hard spheres into glass capillaries. The first one the presence of "particles" (blood cells) is taken into account, the scenario acquires more complexity

Weeks, Eric R.

266

Method and apparatus for uniformly concentrating solar flux for photovoltaic applications  

DOE Patents (OSTI)

This invention is comprised of a dish reflector and method for concentrating moderate solar flux uniformly on a target plane on a solar cell array, the dish having a stepped reflective surface that is characterized by a plurality of ring-like segments arranged about a common axis, and each segment having a concave spherical configuration.

Jorgensen, G.J.; Carasso, M.; Wendelin, T.J.; Lewandowski, A.A.

1991-12-31T23:59:59.000Z

267

Method and apparatus for uniformly concentrating solar flux for photovoltaic applications  

DOE Patents (OSTI)

This invention is comprised of a dish reflector and method for concentrating moderate solar flux uniformly on a target plane on a solar cell array, the dish having a stepped reflective surface that is characterized by a plurality of ring-like segments arranged about a common axis, and each segment having a concave spherical configuration.

Jorgensen, G.J.; Carasso, M.; Wendelin, T.J.; Lewandowski, A.A.

1991-01-01T23:59:59.000Z

268

Method and apparatus for uniformly concentrating solar flux for photovoltaic applications  

DOE Patents (OSTI)

A dish reflector and method for concentrating moderate solar flux uniformly on a target plane on a solar cell array, the dish having a stepped reflective surface that is characterized by a plurality of ring-like segments arranged about a common axis, and each segment having a concave spherical configuration.

Jorgensen, Gary J. (Pine, CO); Carasso, Meir (Lakewood, CO); Wendelin, Timothy J. (Golden, CO); Lewandowski, Allan A. (Evergreen, CO)

1992-01-01T23:59:59.000Z

269

High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrator Application  

DOE Green Energy (OSTI)

The High Efficiency Nanostructured III-V Photovoltaics for Solar Concentrators project seeks to provide new photovoltaic cells for Concentrator Photovoltaics (CPV) Systems with higher cell efficiency, more favorable temperature coefficients and less sensitivity to changes in spectral distribution. The main objective of this project is to provide high efficiency III-V solar cells that will reduce the overall cost per Watt for power generation using CPV systems.This work is focused both on a potential near term application, namely the use of indium arsenide (InAs) QDs to spectrally "tune" the middle (GaAs) cell of a SOA triple junction device to a more favorable effective bandgap, as well as the long term goal of demonstrating intermediate band solar cell effects. The QDs are confined within a high electric field i-region of a standard GaAs solar cell. The extended absorption spectrum (and thus enhanced short circuit current) of the QD solar cell results from the increase in the sub GaAs bandgap spectral response that is achievable as quantum dot layers are introduced into the i-region. We have grown InAs quantum dots by OMVPE technique and optimized the QD growth conditions. Arrays of up to 40 layers of strain balanced quantum dots have been experimentally demonstrated with good material quality, low residual stain and high PL intensity. Quantum dot enhanced solar cells were grown and tested under simulated one sun AM1.5 conditions. Concentrator solar cells have been grown and fabricated with 5-40 layers of QDs. Testing of these devices show the QD cells have improved efficiency compared to baseline devices without QDs. Device modeling and measurement of thermal properties were performed using Crosslight APSYS. Improvements in a triple junction solar cell with the insertion of QDs into the middle current limiting junction was shown to be as high as 29% under one sun illumination for a 10 layer stack QD enhanced triple junction solar cell. QD devices have strong potential for net gains in efficiency at high concentration.

Hubbard, Seth

2012-09-12T23:59:59.000Z

270

NREL: Concentrating Solar Power Research - News  

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

News News Below are news stories related to NREL Concentrating Solar Power research. Subscribe to the RSS feed RSS . Learn about RSS. November 5, 2013 Solar Working Group Releases Standard Contracts A working group representing solar industry stakeholders has developed standard contracts that should help lower transaction costs and make it easier to access low-cost financing for residential and commercial solar power projects. October 24, 2013 NREL Researcher Honored with Hispanic STEM Award A national organization devoted to getting more Hispanics into the fields of science, technology, engineering, and math (STEM), has honored a scientist at the Energy Department's National Renewable Energy Laboratory (NREL) with its annual Outstanding Technical Achievement Award.

271

2009 Concentrating Photovoltaic Solar Technology Assessment  

Science Conference Proceedings (OSTI)

This report investigates manufacturers of concentrating photovoltaic (CPV) systems with a special emphasis on companies that may be ready to deploy one or more 50-MW systems by 2012. The report has three main sections: Detailed profiles of 10 companies that appear likely to be able to field utility-scale deployments by 2012 A market study and forecast for CPV over the period 2012–2020 An appendix, listing contacts and other information about the dozens of CPV vendors that were not included in the detail...

2010-04-13T23:59:59.000Z

272

Acoustic concentration of particles in fluid flow  

DOE Patents (OSTI)

An apparatus for acoustic concentration of particles in a fluid flow includes a substantially acoustically transparent membrane and a vibration generator that define a fluid flow path therebetween. The fluid flow path is in fluid communication with a fluid source and a fluid outlet and the vibration generator is disposed adjacent the fluid flow path and is capable of producing an acoustic field in the fluid flow path. The acoustic field produces at least one pressure minima in the fluid flow path at a predetermined location within the fluid flow path and forces predetermined particles in the fluid flow path to the at least one pressure minima.

Ward, Michael D. (Los Alamos, NM); Kaduchak, Gregory (Los Alamos, NM)

2010-11-23T23:59:59.000Z

273

Suspension Hydrogen Reduction of Iron Oxide Concentrates  

DOE Green Energy (OSTI)

The objective of the project is to develop a new ironmaking technology based on hydrogen and fine iron oxide concentrates in a suspension reduction process. The ultimate objective of the new technology is to replace the blast furnace and to drastically reduce CO2 emissions in the steel industry. The goals of this phase of development are; the performance of detailed material and energy balances, thermochemical and equilibrium calculations for sulfur and phosphorus impurities, the determination of the complete kinetics of hydrogen reduction and bench-scale testing of the suspension reduction process using a large laboratory flash reactor.

H.Y. Sohn

2008-03-31T23:59:59.000Z

274

WAvelength selection for optimal determination of glucose concentration in biological media  

E-Print Network (OSTI)

Current research in the large scale production of cell culture samples will require the use of a dedicated monitoring system capable of determining concentrations of the important growth controlling factors within cell culture media. Current methods are limited to bench top laboratory use and require the large amounts of extra resources of space, materials and time. Other researchers have shown the ability to determine glucose concentration in solution through spectroscopic techniques but have required large regions of the electromagnetic spectrum to be accurate. This research presents the results of using wavelength selection routines to decrease the required spectral region to nearly 10% of the original while achieving similar or in some instance better predictive accuracy. Using concentrations of 0-27.3mM glucose in solution, predictive errors of 0.3 mM were achieved.

Robinson, Stewart Hughes

1996-01-01T23:59:59.000Z

275

Dish/Engine Systems for Concentrating Solar Power | Department...  

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

DishEngine Systems for Concentrating Solar Power DishEngine Systems for Concentrating Solar Power August 20, 2013 - 5:02pm Addthis The dishengine system is a concentrating solar...

276

Solar kinetics` photovoltaic concentrator module and tracker development  

DOE Green Energy (OSTI)

Solar Kinetics, Inc., has been developing a point-focus concentrating photovoltaic module and tracker system under contract to Sandia National Laboratories. The primary focus of the contract was to achieve a module design that was manufacturable and passed Sandia`s environmental testing. Nine modules of two variations were assembled, tested, and characterized in Phase 1, and results of these tests were promising, with module efficiency approaching the theoretical limit achievable with the components used. The module efficiency was 11.9% at a solar irradiance of 850 W/m{sup 2} and an extrapolated cell temperature of 25{degrees}C. Improvements in module performance are anticipated as cell efficiencies meet their expectations. A 2-kW tracker and controller accommodating 20 modules was designed, built, installed, and operated at Solar Kinetics` test site. The drive used many commercially available components in an innovative arrangement to reduce cost and increase reliability. Backlash and bearing play were controlled by use of preloaded, low slip-stick, synthetic slide bearings. The controller design used a standard industrial programmable logic controller to perform ephemeris calculations, operate the actuators, and monitor encoders.

White, D.L.; Howell, B. [Solar Kinetics, Inc., Dallas, TX (United States)

1995-11-01T23:59:59.000Z

277

Single-junction solar cells with the optimum band gap for ...  

A single-junction solar cell having the ideal band gap for terrestrial concentrator applications. Computer modeling studies of single-junction solar cells have shown ...

278

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS  

Science Conference Proceedings (OSTI)

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

NA

2004-11-22T23:59:59.000Z

279

Black Carbon Concentrations and Diesel Vehicle Emission Factors...  

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

Black Carbon Concentrations and Diesel Vehicle Emission Factors Derived from Coefficient of Haze Measurements in California: 1967-2003 Title Black Carbon Concentrations and Diesel...

280

Low Cost High Concentration PV Systems for Utility Power Generation...  

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

Other Agencies You are here Home Low Cost High Concentration PV Systems for Utility Power Generation Low Cost High Concentration PV Systems for Utility Power Generation An...

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


281

Low Cost High Concentration PV Systems for Utility Power Generation...  

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

Other Agencies You are here Home Low Cost High Concentration PV Systems for Utility Power Generation Amonix, Inc. Low Cost High Concentration PV Systems for Utility Power...

282

Concentrating Solar Power: Best Practices Handbook for the Collection...  

Open Energy Info (EERE)

Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data Jump to: navigation, search Tool Summary Name: Concentrating Solar Power: Best...

283

The Measurement of the Moisture Concentration of Selected Test...  

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

The Measurement of the Moisture Concentration of Selected Test Model Ore Zones (April 1977) The Measurement of the Moisture Concentration of Selected Test Model Ore Zones (April...

284

Category:Concentrating Solar Power | Open Energy Information  

Open Energy Info (EERE)

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285

Concentrations of fine, ultrafine, and black carbon particles...  

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

Concentrations of fine, ultrafine, and black carbon particles in auto-rickshaws in New Delhi, India Title Concentrations of fine, ultrafine, and black carbon particles in...

286

Factors affecting the indoor concentrations of carbonaceous aerosols...  

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

Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin Title Factors affecting the indoor concentrations of carbonaceous aerosols of outdoor origin...

287

NREL: Concentrating Solar Power Research - Systems Analysis  

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

Systems Analysis Systems Analysis Featured Resource Learn more about NREL's capabilities in modeling and analysis of CSP Systems. NREL and other national laboratories support U.S. Department of Energy (DOE) systems analysis activities to evaluate and validate the cost, performance, durability, and grid penetration impacts for concentrating solar power (CSP) technologies. DOE's systems analysis program focuses on the greatest opportunities for impact, based on estimates of the current and future costs of CSP plants, subsystems, and components. Opportunities and Potential Impact The DOE SunShot Initiative to reduce the installed cost of solar energy systems by 75% by the end of the decade will require low-cost configurations that are easy to integrate into the electric grid. Systems

288

Exploratory study of complexant concentrate waste processing  

SciTech Connect

The purpose of this exploratory study, conducted by Pacific Northwest Laboratory for Westinghouse Hanford Company, was to determine the effect of applying advanced chemical separations technologies to the processing and disposal of high-level wastes (HLW) stored in underground tanks. The major goals of this study were to determine (1) if the wastes can be partitioned into a small volume of HLW plus a large volume of low-level waste (LLW), and (2) if the activity in the LLW can be lowered enough to meet NRC Class LLW criteria. This report presents the results obtained in a brief scouting study of various processes for separating radionuclides from Hanford complexant concentrate (CC) waste.

Lumetta, G.J.; Bray, L.A.; Kurath, D.E.; Morrey, J.R.; Swanson, J.L.; Wester, D.W.

1993-02-01T23:59:59.000Z

289

Concentrating Solar Power strategic plan summary  

SciTech Connect

A strategic plan for Concentrating Solar Power (CSP) -- A Bright Path to the Future -- was completed and released by the US Department of Energy`s Office of Solar Thermal, Biomass Power, and Hydrogen Technologies in December 1996. This strategic plan document will help bring CSP (formerly solar thermal electric) technologies to the marketplace over the course of the next 20 years (1996--2015) -- taking us from the current pre-competitive status closer to full commercialization. The plan, developed in concert with stakeholders, is a living document and will undergo periodic reevaluation as well as revision to reflect changes in the market environment, the progress of the technologies, and the development of new concepts and ideas.

1998-05-01T23:59:59.000Z

290

Development of Concentrating Solar Thermal Power  

E-Print Network (OSTI)

(Draft under Consideration by the World Bank) In May 2004, the World Bank submitted a status report on the GEF co-financed solar thermal portfolio to the GEF Council. In response to Council comments, the Bank subsequently commissioned an external assessment of the World Bank/GEF’s strategy for the market development of concentrating solar thermal power. The consultant was selected through a competitive procurement process, following World Bank procedures. The selected consortium, the Global Research Alliance, is led by CSIR-South Africa, and includes the Fraunhofer Institute for Systems and Innovation Research, Fraunhofer Institute for Solar Energy Systems, and CSIRO-Australia. The report’s findings and recommendations are now under consideration by the World Bank. Council Members are invited to comment on the report, by July 15, 2005.

Gef Council; Concentrating Solar; Thermal Power; Copied To Mr. Rohit Khanna; Senior Operations Officer; Steve Szewczuk; Csir South Africa; Thomas Engelmann; Michael Geyer; Juan Granados; Andreas Haeberle; Haeussermann Tewfik Hasni; David Kearney; Ludger Lorych; Thomas Mancini; Abdellah Mdarhri; Paul Nava; Joachim Nick-leptin; Hani El Nokrashy; Robert Pitz; Klaus-peter Pischke; Hank Price; Jürgen Ratzinger; Thomas Rueckert; David Saul; Franz Trieb; Christine Woerlen

2005-01-01T23:59:59.000Z

291

Steam generation in compound parabolic concentrator collectors  

SciTech Connect

This report describes the advantages of generating steam directly in a nonimaging compound parabolic concentrator (CPC) collector rather than using a heat-transfer fluid and a secondary heat exchanger. The predicted performance advantages from generating steam directly in CPC collectors are significant, and that performance has ben verified using a collector built and tested at Argonne National Laboratory. The collector and the method used to test its operation in a steam-generating mode are described. Test results are included for a 6.4-m/sup 2/ array of evacuated tube collectors with an advanced absorber coating, silver reflectors, and tubes oriented in a north-south configuration. Also described are the test methods and results for indoor testing for heat loss by the collectors and outdoor testing of their instantaneous optical efficiency.

Allen, J.W.; Schertz, W.W.; Wantroba, A.S.

1985-08-01T23:59:59.000Z

292

Toxicity Data to Determine Refrigerant Concentration Limits  

SciTech Connect

This report reviews toxicity data, identifies sources for them, and presents resulting exposure limits for refrigerants for consideration by qualified parties in developing safety guides, standards, codes, and regulations. It outlines a method to calculate an acute toxicity exposure limit (ATEL) and from it a recommended refrigerant concentration limit (RCL) for emergency exposures. The report focuses on acute toxicity with particular attention to lethality, cardiac sensitization, anesthetic and central nervous system effects, and other escape-impairing effects. It addresses R-11, R-12, R-22, R-23, R-113, R-114, R-116, R-123, R-124, R-125, R-134, R-134a, R-E134, R-141b, R-142b, R-143a, R-152a, R-218, R-227ea, R-236fa, R-245ca, R-245fa, R-290, R-500, R-502, R-600a, R-717, and R-744. It summarizes additional data for R-14, R-115, R-170 (ethane), R-C318, R-600 (n-butane), and R-1270 (propylene) to enable calculation of limits for blends incorporating them. The report summarizes the data a nd related safety information, including classifications and flammability data. It also presents a series of tables with proposed ATEL and RCL concentrations-in dimensionless form and the latter also in both metric (SI) and inch-pound (IP) units of measure-for both the cited refrigerants and 66 zerotropic and azeotropic blends. They include common refrigerants, such as R-404A, R-407C, R-410A, and R-507A, as well as others in commercial or developmental status. Appendices provide profiles for the cited single-compound refrigerants and for R-500 and R-502 as well as narrative toxicity summaries for common refrigerants. The report includes an extensive set of references.

Calm, James M.

2000-09-30T23:59:59.000Z

293

DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS  

Science Conference Proceedings (OSTI)

The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

P. Bernot

2005-07-13T23:59:59.000Z

294

Performance and testing of a stationary concentrating collector. [Compound parabolic concentrators coupled to tubular evacuated receivers  

DOE Green Energy (OSTI)

The development of nonimaging solar collectors for heating and cooling applications is reported. A totally stationary concentrating collector has been designed, built, and tested. The collectors employ compound parabolic concentrators coupled to tubular evacuated receivers. Performance of the collector is substantially better than flat plate collectors, and the collectors are suitable for powering mechanically driven air conditioning systems as well as conventional absorption cycle machines. This collector concept was awarded an IR-100 award by Industrial Research Magazine as one of the 100 most significant new developments in 1977.

Cole, R L; Allen, J W; Levitz, N M; McIntire, W R; Schertz, W W

1977-01-01T23:59:59.000Z

295

SunShot Initiative: Concentrating Solar Power Staff  

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

Concentrating Solar Power Staff Concentrating Solar Power Staff to someone by E-mail Share SunShot Initiative: Concentrating Solar Power Staff on Facebook Tweet about SunShot Initiative: Concentrating Solar Power Staff on Twitter Bookmark SunShot Initiative: Concentrating Solar Power Staff on Google Bookmark SunShot Initiative: Concentrating Solar Power Staff on Delicious Rank SunShot Initiative: Concentrating Solar Power Staff on Digg Find More places to share SunShot Initiative: Concentrating Solar Power Staff on AddThis.com... Accomplishments Visiting the SunShot Office Fellowships Postdoctoral Research Contacts Staff Concentrating Solar Power Staff The SunShot Initiative concentrating solar power (CSP) program competitively funds and actively manages the efforts of industry, national laboratories, and universities working to make large-scale dispatchable

296

Maximally concentrating optics for photovoltaic solar energy conversion. Technical progress report, [July 1, 1984--January 31, 1985  

DOE Green Energy (OSTI)

Use of a two-stage concentrator with a fresnel lens primary and a nonimaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. Some preliminary ray trace studies have shown that with planar lenses, an increase in angular acceptance for a given geometric concentration to about 2/3 of the maximum theoretical limit can be achieved. To demonstrate this, two preprototype concentrators, each having a geometric concentration of 248:1 for a 0.635cm (0.25 inch) diameter cell, have been designed, built, and tested. Measurements of the angular response show an acceptance of 8{degrees} (full angle) which is drastically better than the 1{degrees}--2{degrees} achievable without a secondary, and is in excellent agreement with the ray trace predictions. For these preprototypes, passive cooling was sufficient to prevent any thermal problems for both the cell and secondary. No problems associated with nouuniform cell illumination were found, as evidenced by the fill factor of 71%--73% measured under concentration. Initial measurements of the system electrical efficiency lie in the range 7.5%--9.9% for a variety of individual cells.

O`Gallagher, J.J.

1985-03-07T23:59:59.000Z

297

Capacity Value of Concentrating Solar Power Plants  

DOE Green Energy (OSTI)

This study estimates the capacity value of a concentrating solar power (CSP) plant at a variety of locations within the western United States. This is done by optimizing the operation of the CSP plant and by using the effective load carrying capability (ELCC) metric, which is a standard reliability-based capacity value estimation technique. Although the ELCC metric is the most accurate estimation technique, we show that a simpler capacity-factor-based approximation method can closely estimate the ELCC value. Without storage, the capacity value of CSP plants varies widely depending on the year and solar multiple. The average capacity value of plants evaluated ranged from 45%?90% with a solar multiple range of 1.0-1.5. When introducing thermal energy storage (TES), the capacity value of the CSP plant is more difficult to estimate since one must account for energy in storage. We apply a capacity-factor-based technique under two different market settings: an energy-only market and an energy and capacity market. Our results show that adding TES to a CSP plant can increase its capacity value significantly at all of the locations. Adding a single hour of TES significantly increases the capacity value above the no-TES case, and with four hours of storage or more, the average capacity value at all locations exceeds 90%.

Madaeni, S. H.; Sioshansi, R.; Denholm, P.

2011-06-01T23:59:59.000Z

298

Design of nonimaging concentrators as second stages in tandem with image-forming first-stage concentrators  

SciTech Connect

The flux concentration of paraboloidal mirrors of short focal ratio may be enhanced to near the thermodynamic limit by the addition of low concentration (2-4X) nonimaging concentrators such as compound elliptical concentrators or hyperbolic trumpets. An outline of the design procedure and the results of ray trace analysis are presented.

Greenman, P. (Univ. of Chicago, IL); O'Gallagher, J.; Winston, R.; Welford, W.T.

1980-01-01T23:59:59.000Z

299

Cell separator and cell  

SciTech Connect

There is disclosed a novel cell separator made of a grafted membrane comprising a polyethylene film which is graft copolymerized with a monomer having an ion exchange group, characterized in that said membrane has an area which is not grafted at all or an area of low degree grafting. By making use of this membrane, a small size and thin cell having excellent performance as well as satisfactory mechanical strength can be produced at low cost with great advantages.

Ishigaki, I.; Machi, S.; Murata, K.; Okada, T.; Senoo, K.; Sugo, T.; Tanso, S.

1981-09-01T23:59:59.000Z

300

SunShot Initiative: Baseload Concentrating Solar Power Generation  

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

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

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


301

SunShot Initiative: Concentrating Solar Power Competitive Awards  

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

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

302

SunShot Initiative: Concentrated Solar Thermoelectric Power  

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

Concentrated Solar Thermoelectric Concentrated Solar Thermoelectric Power to someone by E-mail Share SunShot Initiative: Concentrated Solar Thermoelectric Power on Facebook Tweet about SunShot Initiative: Concentrated Solar Thermoelectric Power on Twitter Bookmark SunShot Initiative: Concentrated Solar Thermoelectric Power on Google Bookmark SunShot Initiative: Concentrated Solar Thermoelectric Power on Delicious Rank SunShot Initiative: Concentrated Solar Thermoelectric Power on Digg Find More places to share SunShot Initiative: Concentrated Solar Thermoelectric Power on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act Baseload CSP SunShot Multidisciplinary University Research Initiative CSP Heat Integration for Baseload Renewable Energy Deployment

303

AMMONIA CONCENTRATION IN SALTSTONE HEADSPACE SUMMARY REPORT  

SciTech Connect

The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar into Tank 50. Saltstone samples were prepared with an 'MCU' type salt solution spiked with ammonia. The ammonia released from the saltstone was captured and analyzed. The ammonia concentration found in the headspace of samples maintained at 95 C and 1 atm was, to 95% confidence, less than or equal to 3.9 mg/L. Tank 50 is fed by several influent streams. The salt solution from Tank 50 is pumped to the salt feed tank (SFT) in the Saltstone Production Facility (SPF). The premix materials cement, slag and fly ash are blended together prior to transfer to the grout mixer. The premix is fed to the grout mixer in the SPF and the salt solution is incorporated into the premix in the grout mixer, yielding saltstone slurry. The saltstone slurry drops into a hopper and then is pumped to the vault. The Saltstone Facility Documented Safety Analysis (DSA) is under revision to accommodate changes in the Composite Lower Flammability Limit (CLFL) from the introduction of Isopar{reg_sign} L into Tank 50. Waste Solidification-Engineering requested that the Savannah River National Laboratory (SRNL) perform testing to characterize the release of ammonia in curing saltstone at 95 C. The test temperature represents the maximum allowable temperature in the Saltstone Disposal Facility (SDF). Ammonia may be present in the salt solution and premix materials, or may be produced by chemical reactions when the premix and salt solution are combined. A final report (SRNS-STI-2008-00120, Rev. 0) will be issued that will cover in more depth the information presented in this report.

Zamecnik, J; Alex Cozzi, A

2008-09-26T23:59:59.000Z

304

CRADA Final Report: Process development for hybrid solar cells  

E-Print Network (OSTI)

III-Nitride Alloys for Solar Power Conversion. ” List ofsolar cells have the potential to reduce the cost of concentrator photovoltaic power

Ager, Joel W

2011-01-01T23:59:59.000Z

305

NREL Measures IMM Solar Cell Performance for CPV (Fact Sheet...  

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

New measurement capability supports the development of high-efficiency solar cells for concentrating photovoltaic (CPV) application. NREL scientists recently completed a set of...

306

Method for detection of extremely low concentration  

DOE Patents (OSTI)

An ultratrace detector system for hand-held gas chromatography having high sensitivity, for example, to emissions generated during production of weapons, biological compounds, drugs, etc. The detector system is insensitive to water, air, helium, argon, oxygen, and CO.sub.2. The detector system is basically composed of a hand-held capillary gas chromatography (GC), an insulated heated redox-chamber, a detection chamber, and a vapor trap. For example, the detector system may use gas phase redox reactions and spectral absorption of mercury vapor. The gas chromatograph initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica--or other metal--aerogel material which acts as an insulator. Compounds easily oxidized by HgO liberate atomic mercury that subsequently pass through a detection chamber which includes a detector cell, such as quartz, that is illuminated with a 254 nm ultra-violet (UV) mercury discharge lamp which generates the exact mercury absorption bands that are used to detect the liberated mercury atoms. Atomic mercury strongly absorbs 254 nm energy is therefore a specific signal for reducing compounds eluting from the capillary GC, whereafter the atomic mercury is trapped for example, in a silicon-aerogel trap.

Andresen, Brian D. (Livermore, CA); Miller, Fred S. (Bethal Island, CA)

2002-01-01T23:59:59.000Z

307

Accelerated Stress Testing of Hydrocarbon-Based Encapsulants for Medium-Concentration CPV Applications  

Science Conference Proceedings (OSTI)

Concentrating photovoltaic (CPV) systems have great potential to reduce photovoltaic (PV) electricity costs because of the relatively low cost of optical components as compared to PV cells. A transparent polymeric material is used to optically couple the PV cell to optical components and is thus exposed to the concentrated light source at elevated temperatures. In this work polymeric encapsulant materials are positioned close to a Xenon arc lamp to expose them to ultraviolet radiation (UV) that is about 42 times as intense as sunlight. Furthermore, different glass types are used as filters to modify the spectral distribution of light in the UV range. A strong sensitivity of non-silicone-based encapsulants to light below ~350 nm is demonstrated. Of all the materials examined in this study, the polydimethyl silicone samples performed the best. The next best material was an ionomer which maintained optical transmission but became photo-oxidized where exposed to the atmosphere.

Kempe, M. D.; Moricone, T. J.; Kilkenny, M.; Zhang, J. Z.

2011-02-01T23:59:59.000Z

308

SunShot Initiative: Scattering Solar Thermal Concentrators  

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

Scattering Solar Thermal Scattering Solar Thermal Concentrators to someone by E-mail Share SunShot Initiative: Scattering Solar Thermal Concentrators on Facebook Tweet about SunShot Initiative: Scattering Solar Thermal Concentrators on Twitter Bookmark SunShot Initiative: Scattering Solar Thermal Concentrators on Google Bookmark SunShot Initiative: Scattering Solar Thermal Concentrators on Delicious Rank SunShot Initiative: Scattering Solar Thermal Concentrators on Digg Find More places to share SunShot Initiative: Scattering Solar Thermal Concentrators on AddThis.com... Concentrating Solar Power Systems Components Competitive Awards CSP Research & Development Thermal Storage CSP Recovery Act Baseload CSP SunShot Multidisciplinary University Research Initiative CSP Heat Integration for Baseload Renewable Energy Deployment

309

SunShot Initiative: Concentrating Solar Power Newsletter  

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

Information Resources Information Resources Printable Version Share this resource Send a link to SunShot Initiative: Concentrating Solar Power Newsletter to someone by E-mail Share SunShot Initiative: Concentrating Solar Power Newsletter on Facebook Tweet about SunShot Initiative: Concentrating Solar Power Newsletter on Twitter Bookmark SunShot Initiative: Concentrating Solar Power Newsletter on Google Bookmark SunShot Initiative: Concentrating Solar Power Newsletter on Delicious Rank SunShot Initiative: Concentrating Solar Power Newsletter on Digg Find More places to share SunShot Initiative: Concentrating Solar Power Newsletter on AddThis.com... Publications Newsletter Resource Center Multimedia Meetings & Workshops Solar Innovation Timeline Solar Career Map Glossary Concentrating Solar Power Newsletter

310

Lithium Diisopropylamide: Oligomer Structures at Low Ligand Concentrations  

E-Print Network (OSTI)

Lithium Diisopropylamide: Oligomer Structures at Low Ligand Concentrations Jennifer L. Rutherford-dimensional 6Li and 15N NMR spectroscopic studies of lithium diisopropylamide (LDA) solvated ligand concentrations are discussed. Introduction Spectroscopic studies of lithium amides at low ligand

Collum, David B.

311

SunShot Initiative: Low-Cost, Lightweight Solar Concentrators  

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

Low-Cost, Lightweight Solar Concentrators to someone by E-mail Share SunShot Initiative: Low-Cost, Lightweight Solar Concentrators on Facebook Tweet about SunShot Initiative:...

312

The Formation of Concentric Vorticity Structures in Typhoons  

Science Conference Proceedings (OSTI)

An important issue in the formation of concentric eyewalls in a tropical cyclone is the development of a symmetric structure from asymmetric convection. It is proposed herein, with the aid of a nondivergent barotropic model, that concentric ...

H-C. Kuo; L-Y. Lin; C-P. Chang; R. T. Williams

2004-11-01T23:59:59.000Z

313

Optimizing mixer geometries for dielectrophoretic micro-concentrators  

E-Print Network (OSTI)

Dielectrophoretic (DEP) force, generated by interdigitated electrodes (IDEs), has been utilized to capture bio-particles for microfluidic concentration. However, due to the localized DEP force, DEP-based ,/ -concentrators ...

Lee, Hsu-Yi

2006-01-01T23:59:59.000Z

314

Improving Concentration Measures Used for Evaluating Air Quality Models  

Science Conference Proceedings (OSTI)

An unfortunate difficulty in model evaluation is that the concentration measure that most models predict, namely the ensemble mean concentration under the plume centerline (or at some location relative to the plume centerline), cannot be measured ...

Russell F. Lee; John S. Irwin

1997-08-01T23:59:59.000Z

315

Process of concentrating ethanol from dilute aqueous solutions thereof  

DOE Patents (OSTI)

Relatively dilute aqueous solutions of ethanol are concentrated by passage through a bed of a crystalline silica polymorph, such as silicalite, to adsorb the ethanol with residual dilute feed in contact with the bed, which is displaced by passing concentrated aqueous ethanol through the bed without displacing the adsorbed ethanol. A product concentrate is then obtained by removing the adsorbed ethanol from the bed together with at least a portion of the concentrated aqueous ethanol used as the displacer liquid. This process permits ethanol to be concentrated from dilute fermentation beers, which may contain from 6 to 10% ethanol, to obtain a concentrate product at very low energy cost having an ethanol concentration in excess of 95%, such as a concentration of from 98 to 99.5%. 5 figs.

Oulman, C.S.; Chriswell, C.D.

1981-07-07T23:59:59.000Z

316

Process of concentrating ethanol from dilute aqueous solutions thereof  

DOE Patents (OSTI)

Relatively dilute aqueous solutions of ethanol are concentrated by passage through a bed of a crystalline silica polymorph, such as silicalite, to adsorb the ethanol with residual dilute feed in contact with the bed, which is displaced by passing concentrated aqueous ethanol through the bed without displacing the adsorbed ethanol. A product concentrate is then obtained by removing the adsorbed ethanol from the bed together with at least a portion of the concentrated aqueous ethanol used as the displacer liquid. This process permits ethanol to be concentrated from dilute fermentation beers, which may contain from 6 to 10% ethanol, to obtain a concentrate product at very low energy cost having an ethanol concentration in excess of 95%, such as a concentration of from 98 to 99.5%.

Oulman, Charles S. (Ames, IA); Chriswell, Colin D. (Slater, IA)

1981-07-07T23:59:59.000Z

317

SunShot Initiative: Concentrating Solar Power Staff Profiles  

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

Printable Version Share this resource Send a link to SunShot Initiative: Concentrating Solar Power Staff Profiles to someone by E-mail Share SunShot Initiative: Concentrating...

318

Concentrating Solar Power Program Review 2013 (Book) (Revised)  

SciTech Connect

This U.S. Department of Energy (DOE) Concentrating Solar Power Program Review Meeting booklet will be provided to attendees at the Concentrating Solar Power Review Meeting in Phoenix, Arizona on April 23-25, 2013.

Not Available

2013-06-01T23:59:59.000Z

319

Geometrical vector flux sinks and ideal flux concentrators  

SciTech Connect

The description of ideal flux concentrators as shapes that do not disturb the geometrical vector flux field is extended to all the known types of ideal flux concentrators. This is accomplished, in part, by the introduction of vector flux sinks.

Greenman, P.

1981-06-01T23:59:59.000Z

320

Efficiency enhancement of luminescent solar concentrations for photovoltaic technologies  

E-Print Network (OSTI)

dyes. Photovoltaic (PV) solar cells are used to attach atis fa- vored by the silicon PV solar cells for the LSC PVemission properties for PV solar cells. We studied e?ect of

Wang, Chunhua

2011-01-01T23:59:59.000Z

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


321

64 kW concentrator Photovoltaics Application Test Center. Volume. Final report  

DOE Green Energy (OSTI)

Kaman Sciences Corporation has designed a 64 kW Concentrating Photovoltaic Applications Test Center (APTEC). The APTEC employs a combined concentrating photovoltaic array in a total energy system application for load sharing the electric and thermal demands of a large computer center with the interfaced electric and natural gas utility. The photovoltaic array is composed of two-axis tracking heliostats of Fresnel lens concentrating, silicon solar cell modules. The modules are cooled with a fluid which transfers heat to a ground coupled heat sink/storage unit for subsequent use in meeting the computer center's thermal load demand. The combined photovoltaic power system shares basic components - a power conditioning unit, batteries and thermal conditioning equipment - with the electric and natural gas utility service, improving the computer center's operating availability time and displacing a portion of the fossil fuel required to power the computer center with solar energy. The detailed system design is reported.

Jardine, D.M.; Jones, D.W.

1980-06-01T23:59:59.000Z

322

Simultaneous and rapid determination of multiple component concentrations in a Kraft liquor process stream  

DOE Patents (OSTI)

The present invention is a rapid method of determining the concentration of the major components in a chemical stream. The present invention is also a simple, low cost, device of determining the in-situ concentration of the major components in a chemical stream. In particular, the present invention provides a useful method for simultaneously determining the concentrations of sodium hydroxide, sodium sulfide and sodium carbonate in aqueous kraft pulping liquors through use of an attenuated total reflectance (ATR) tunnel flow cell or optical probe capable of producing a ultraviolet absorbency spectrum over a wavelength of 190 to 300 nm. In addition, the present invention eliminates the need for manual sampling and dilution previously required to generate analyzable samples. The inventive method can be used in Kraft pulping operations to control white liquor causticizing efficiency, sulfate reduction efficiency in green liquor, oxidation efficiency for oxidized white liquor and the active and effective alkali charge to kraft pulping operations.

Li, Jian (Marietta, GA); Chai, Xin Sheng (Atlanta, GA); Zhu, Junyoung (Marietta, GA)

2008-06-24T23:59:59.000Z

323

Energy Basics: Power Tower Systems for Concentrating Solar Power  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Concentrating Solar Power Linear...

324

Energy Basics: Thermal Storage Systems for Concentrating Solar...  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Concentrating Solar Power Linear...

325

Energy Basics: Dish/Engine Systems for Concentrating Solar Power  

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

Energy Basics Renewable Energy Printable Version Share this resource Biomass Geothermal Hydrogen Hydropower Ocean Solar Photovoltaics Concentrating Solar Power Linear...

326

Processing of Lead, Zinc, Copper and Nickel Concentrates  

Science Conference Proceedings (OSTI)

Abstract Scope, Processing of copper, zinc, lead and nickel concentrates is becoming more challenging due increasingly complex mineralogy. Smelters are  ...

327

Applications of Concentrating Solar Power in Materials Production  

Science Conference Proceedings (OSTI)

Symposium, Alternative Energy Resources for Metals and Materials Production Symposium. Presentation Title, Applications of Concentrating Solar Power in ...

328

Durability of Poly(Methyl Methacrylate) Lenses Used in Concentrating Photovoltaic Technology (Revised) (Presentation)  

DOE Green Energy (OSTI)

Concentrating photovoltaic (CPV) technology recently gained interest based on its expected low levelized cost of electricity, high efficiency, and scalability. Many CPV systems employ Fresnel lenses composed of poly(methyl methacrylate) (PMMA) to obtain a high optical flux density on the cell. The optical and mechanical durability of these lenses, however, is not well established relative to the desired surface life of 30 years. Our research aims to quantify the expected lifetime of PMMA in key market locations (FL, AZ, and CO).

Miller, D. C.; Carloni, J. D.; Pankow, J. W.; Gjersing, E. L.; To, B.; Packard, C. E.; Kennedy, C. E.; Kurtz, S. R.

2012-01-01T23:59:59.000Z

329

Compound parabolic concentrators for narrowband wireless infrared receivers  

E-Print Network (OSTI)

Compound parabolic concentrators for narrowband wireless infrared receivers Keang-Po Ho Joseph M and hollow compound parabolic concentrators (CPCs), for use in free-space infrared communication receivers terms: compound parabolic concentrators (CPCs); optical bandpass fil- ters; Monte Carlo ray tracing

Kahn, Joseph M.

330

Minimum-mirror-area single-stage solar concentrators  

SciTech Connect

A means of generating a comcentrating mirror of minimum size for a given average flux-concentration output is outlined. The method is useful for acceptance angles typical of those required for tilting and tracking solar concentrators and can result in substantial cost savings when expensive mirrors (i.e.,glass) are used. Comparisons are made with compound parabolic concentrators.

Mills, D.; Harting, E.; Giutronich, J.E.; Cellich, W.; Morton, A.; Walker, I.

1980-12-01T23:59:59.000Z

331

Photovoltaic Cells  

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

Photovoltaic (PV) cells, or solar cells, take advantage of the photoelectric effect to produce electricity. PV cells are the building blocks of all PV systems because they are the devices that...

332

Key Physical Mechanisms in Nanostructured Solar Cells  

DOE Green Energy (OSTI)

The objective of the project was to study both theoretically and experimentally the excitation, recombination and transport properties required for nanostructured solar cells to deliver energy conversion efficiencies well in excess of conventional limits. These objectives were met by concentrating on three key areas, namely, investigation of physical mechanisms present in nanostructured solar cells, characterization of loss mechanisms in nanostructured solar cells and determining the properties required of nanostructured solar cells in order to achieve high efficiency and the design implications.

Dr Stephan Bremner

2010-07-21T23:59:59.000Z

333

Design of nonimaging concentrators as second stages in tandem with image-forming first-stage concentrators  

SciTech Connect

We show how paraboloidal mirrors of short focal ratio and similar systems can have their flux concentration enhanced to near the thermodynamic limit by the addition of nonimaging compound elliptical concentrators.

Winston, R.; Welford, W.T.

1980-02-01T23:59:59.000Z

334

cell tree  

Science Conference Proceedings (OSTI)

NIST. cell tree. (data structure). ... Concave objects are decomposed into convex pieces. Each convex piece is indexed in every cell which it overlaps. ...

2013-05-08T23:59:59.000Z

335

THERMOCHEMICAL HEAT STORAGE FOR CONCENTRATED SOLAR POWER  

SciTech Connect

Thermal energy storage (TES) is an integral part of a concentrated solar power (CSP) system. It enables plant operators to generate electricity beyond on sun hours and supply power to the grid to meet peak demand. Current CSP sensible heat storage systems employ molten salts as both the heat transfer fluid and the heat storage media. These systems have an upper operating temperature limit of around 400 C. Future TES systems are expected to operate at temperatures between 600 C to 1000 C for higher thermal efficiencies which should result in lower electricity cost. To meet future operating temperature and electricity cost requirements, a TES concept utilizing thermochemical cycles (TCs) based on multivalent solid oxides was proposed. The system employs a pair of reduction and oxidation (REDOX) reactions to store and release heat. In the storage step, hot air from the solar receiver is used to reduce the oxidation state of an oxide cation, e.g. Fe3+ to Fe2+. Heat energy is thus stored as chemical bonds and the oxide is charged. To discharge the stored energy, the reduced oxide is re-oxidized in air and heat is released. Air is used as both the heat transfer fluid and reactant and no storage of fluid is needed. This project investigated the engineering and economic feasibility of this proposed TES concept. The DOE storage cost and LCOE targets are $15/kWh and $0.09/kWh respectively. Sixteen pure oxide cycles were identified through thermodynamic calculations and literature information. Data showed the kinetics of re-oxidation of the various oxides to be a key barrier to implementing the proposed concept. A down selection was carried out based on operating temperature, materials costs and preliminary laboratory measurements. Cobalt oxide, manganese oxide and barium oxide were selected for developmental studies to improve their REDOX reaction kinetics. A novel approach utilizing mixed oxides to improve the REDOX kinetics of the selected oxides was proposed. It partially replaces some of the primary oxide cations with selected secondary cations. This causes a lattice charge imbalance and increases the anion vacancy density. Such vacancies enhance the ionic mass transport and lead to faster re-oxidation. Reoxidation fractions of Mn3O4 to Mn2O3 and CoO to Co3O4 were improved by up to 16 fold through the addition of a secondary oxide. However, no improvement was obtained in barium based mixed oxides. In addition to enhancing the short term re-oxidation kinetics, it was found that the use of mixed oxides also help to stabilize or even improve the TES properties after long term thermal cycling. Part of this improvement could be attributed to a reduced grain size in the mixed oxides. Based on the measurement results, manganese-iron, cobalt-aluminum and cobalt iron mixed oxides have been proposed for future engineering scale demonstration. Using the cobalt and manganese mixed oxides, we were able to demonstrate charge and discharge of the TES media in both a bench top fixed bed and a rotary kiln-moving bed reactor. Operations of the fixed bed configuration are straight forward but require a large mass flow rate and higher fluid temperature for charging. The rotary kiln makes direct solar irradiation possible and provides significantly better heat transfer, but designs to transport the TES oxide in and out of the reactor will need to be defined. The final reactor and system design will have to be based on the economics of the CSP plant. A materials compatibility study was also conducted and it identified Inconel 625 as a suitable high temperature engineering material to construct a reactor holding either cobalt or manganese mixed oxides. To assess the economics of such a CSP plant, a packed bed reactor model was established as a baseline. Measured cobalt-aluminum oxide reaction kinetics were applied to the model and the influences of bed properties and process parameters on the overall system design were investigated. The optimal TES system design was found to be a network of eight fixed bed reactors at 18.75 MWth each with charge and

PROJECT STAFF

2011-10-31T23:59:59.000Z

336

Method for sensing and measuring a concentration or partial pressure of a reactant used in a redox reaction  

DOE Patents (OSTI)

A method for sensing or measuring the partial pressure or concentration of an electroactive species used in conjunction with an electrolyte, the method being characterized by providing a constant current between an anode and a cathode of an electrolyte-containing cell, while measuring changes in voltage that occur between either the anode and cathode or between a reference electrode and one of the main electrodes of the cell, thereby to determine the concentration or partial pressure of the electro-active species as a function of said measured voltage changes. The method of the invention can be practiced using either a cell having only an anode and a cathode, or using a cell having an anode and a cathode in combination with a reference electrode. Accurate measurements of small concentrations or partial pressures of electro-active species are obtainable with the method of the invention, by using constant currents of only a few microamperes between the anode and cathode of the cell, while the concentration-determining voltage is measured.

Findl, E.

1984-12-21T23:59:59.000Z

337

NREL: Energy Analysis - Concentrating Solar Power Results - Life Cycle  

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

Concentrating Solar Power Results - Life Cycle Assessment Harmonization Concentrating Solar Power Results - Life Cycle Assessment Harmonization Life Cycle Greenhouse Gas Emissions from Concentrating Solar Power (Factsheet) Cover of the Life Cycle Greenhouse Gas Emissions from Concentrating Solar Power Download the Factsheet Flowchart that shows the life cycle stages for concentrating solar power systems. For help reading this chart, please contact the webmaster. Figure 1. Process flow diagram illustrating the life cycle stages for concentrating solar power (CSP) systems. The yellow box defined by the grey line shows the systems boundaries assumed in harmonization. Enlarge image NREL developed and applied a systematic approach to review literature on life cycle assessments of concentrating solar power (CSP) systems, identify

338

Energy 101: Concentrating Solar Power | Department of Energy  

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

Concentrating Solar Power Concentrating Solar Power Energy 101: Concentrating Solar Power Addthis Below is the text version for the Energy 101: Concentrating Solar Power video. The video opens with the words "Energy 101: Concentrating Solar Power." OK. Take the natural heat from the sun, reflect it against a mirror, focus all of that heat on one area, send it through a power system, and you've got a renewable way of making electricity. It's called concentrating solar power, or CSP. Caption: Concentrating Solar Power (CSP): Focuses the sun's heat to make steam and electricity. Now, there are many types of CSP technologies. Towers, dishes, linear mirrors, and troughs. The video goes through a quick panorama of several different types, and several different views, of all of the different types of CSP. Finally, it

339

Concentrating Solar Power Services CSP Services | Open Energy Information  

Open Energy Info (EERE)

Concentrating Solar Power Services CSP Services Concentrating Solar Power Services CSP Services Jump to: navigation, search Name Concentrating Solar Power Services (CSP Services) Place Cologne, Germany Zip D-51143 Sector Solar Product A spin-out of the DLR Institute of Technical Thermodynamics, providing consulting, due diligence and component testing for Solar Thermal Electricity Generation (STEG). References Concentrating Solar Power Services (CSP Services)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Concentrating Solar Power Services (CSP Services) is a company located in Cologne, Germany . References ↑ "Concentrating Solar Power Services (CSP Services)" Retrieved from "http://en.openei.org/w/index.php?title=Concentrating_Solar_Power_Services_CSP_Services&oldid=343830

340

Concentrating Solar Power Resources and Technologies | Department of Energy  

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

Concentrating Solar Power Resources and Technologies Concentrating Solar Power Resources and Technologies Concentrating Solar Power Resources and Technologies October 7, 2013 - 11:47am Addthis Photo of a CSP dish glistening in the sun. Multiple solar mirrors reflect sunlight onto a collector. CSP systems concentrate solar heat onto a collector, which powers a turbine to generate electricity. This page provides a brief overview of concentrating solar power (CSP) technologies supplemented by specific information to apply CSP within the Federal sector. Overview Concentrating solar power technologies produce electricity by concentrating the sun's energy using reflective devices, such as troughs or mirror panels, to reflect sunlight onto a receiver. The resulting high-temperature heat is used to power a conventional turbine to produce electricity.

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


341

Series cell light extinction monitor  

DOE Patents (OSTI)

A method and apparatus for using the light extinction measurements from two or more light cells positioned along a gasflow chamber in which the gas volumetric rate is known to determine particle number concentration and mass concentration of an aerosol independent of extinction coefficient and to determine estimates for particle size and mass concentrations. The invention is dependent of particle size. This invention is independent of particle size. This invention has application to measurements made during a severe nuclear reactor fuel damage test. 11 figs.

Novick, V.J.

1989-02-15T23:59:59.000Z

342

Standard Test Method for Electrical Performance of Concentrator Terrestrial Photovoltaic Modules and Systems Under Natural Sunlight  

E-Print Network (OSTI)

1.1 This test method covers the determination of the electrical performance of photovoltaic concentrator modules and systems under natural sunlight using a normal incidence pyrheliometer. 1.2 The test method is limited to module assemblies and systems where the geometric concentration ratio specified by the manufacturer is greater than 5. 1.3 This test method applies to concentrators that use passive cooling where the cell temperature is related to the air temperature. 1.4 Measurements under a variety of conditions are allowed; results are reported under a select set of concentrator reporting conditions to facilitate comparison of results. 1.5 This test method applies only to concentrator terrestrial modules and systems. 1.6 This test method assumes that the module or system electrical performance characteristics do not change during the period of test. 1.7 The performance rating determined by this test method applies only at the period of the test, and implies no past or future performance level. 1.8...

American Society for Testing and Materials. Philadelphia

2009-01-01T23:59:59.000Z

343

Direct Imaging of Nanoscale Dissolution of Dicalcium Phosphate Dihydrate by an Organic Ligand: Concentration Matters  

SciTech Connect

Unraveling the kinetics and mechanisms of sparingly soluble calcium orthophosphate (Ca!P) dissolution in the presence of organic acids at microscopic levels is important for an improved understanding in determining the effectiveness of organic acids present in most rhizosphere environments. Herein, we use in situ atomic force microscopy (AFM) coupled with a fluid reaction cell to image dissolution on the (010) face of brushite, CaHPO4 2H2O, in citrate- bearing solutions over a broad concentration range. We directly measure the dependence of molecular step retreat rate on citrate concentration at various pH values and ionic strengths, relevant to soil solution conditions. We find that low concentrations of citrate(10!100 M)inducedareductioninstepretreatratesalongboththe[10 0]Ccand[101] Ccdirections.However,at higher concentrations (exceeding 0.1 mM), this inhibitory effect was reversed with step retreat speeds increasing rapidly. These results demonstrate that the concentration-dependent modulation of nanoscale Ca!P phase dissolution by citrate may be applied to analyze the controversial role of organic acids in enhancing Ca!P mineral dissolution in a more complex rhizosphere environment. These in situ observations may contribute to resolving the previously unrecognized interactions of root exudates (low molecular weight organic acids) and sparingly soluble Ca!P minerals.

Qin, Lihong [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Zhang, Wenjun [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Lu, Jianwei [Huazhong Agricultural University, China] [Huazhong Agricultural University, China; Stack, Andrew G [ORNL] [ORNL; Wang, Lijun [Huazhong Agricultural University, China] [Huazhong Agricultural University, China

2013-01-01T23:59:59.000Z

344

Fuel Cell Technologies Office: Fuel Cells  

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

Cells Search Search Help Fuel Cells EERE Fuel Cell Technologies Office Fuel Cells Printable Version Share this resource Send a link to Fuel Cell Technologies Office: Fuel...

345

Maximally concentrating optics for photovoltaic solar energy conversion. Technical progress report, [July 1, 1985--February 15, 1986  

DOE Green Energy (OSTI)

The use of a two-stage concentrator with a fresnel lens primary and a non-imaging dielectric totally internally reflecting secondary, has unique advantages for photovoltaic concentration. This new design has a much larger acceptance angle than the conventional lens-cell concentrating system. In the continuation of this research, an optimally designed prototype which employs a 13.6-cm diameter flat fresnel tons as the primary focusing device, a dielectric compound hyperbolic concentrator (DCHC) as secondary and a 1-cm diameter high-concentration cell for electricity conversion has been built, tested and analyzed. Measurements under sunlight show that it has an angular acceptance of {plus_minus}3.6 degrees, which is dramatically better than the {plus_minus}0.5 degree achievable without a secondary concentrator. This performance agrees well with theoretical ray-tracing predictions. The secondary shows an optical efficiency of (91{plus_minus}2)% at normal incidence. Combining with the primary fresnel tens which has an optical efficiency of (82{plus_minus}2)%, tho two-stage system yields a total optical efficiency of (7l{plus_minus}2)%. The measurement of the system electrical performance yielded a net electrical efficiency of 11.9%. No problems associated with non-uniform cell illumination were found, as evidenced by the excellent fill factor of (79{plus_minus}2)% measured under concentration. The secondary geometrical properties and the optimal two-stage design procedures for various primary- cell combinations were systematical studied. A general design principle has been developed.

Winston, R.; O`Gallagher, J.; Ning, X.

1986-02-27T23:59:59.000Z

346

$60 Million to Fund Projects Advancing Concentrating Solar Power |  

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

$60 Million to Fund Projects Advancing Concentrating Solar Power $60 Million to Fund Projects Advancing Concentrating Solar Power $60 Million to Fund Projects Advancing Concentrating Solar Power November 8, 2011 - 10:34am Addthis A 101 video on concentrating solar panel systems. | Courtesy of the Energy Department Jesse Gary Solar Energy Technologies Program On Tuesday, October 25, the Energy Department's SunShot initiative announced a $60 million funding opportunity (FOA) to advance concentrating solar power in the United States. The SunShot program seeks to support research into technologies with potential to dramatically increase efficiency, lower costs, and deliver more reliable performance than existing commercial and near-commercial concentrating solar power (CSP) systems. The Department expects to fund 20 to 22 projects, and we encourage

347

ARM - Evaluation Product - Droplet Number Concentration Value-Added Product  

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

ProductsDroplet Number Concentration Value-Added ProductsDroplet Number Concentration Value-Added Product Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Droplet Number Concentration Value-Added Product 2005.01.01 - 2010.12.30 Site(s) SGP General Description Cloud droplet number concentration is an important factor in understanding aerosol-cloud interactions. As aerosol concentration increases, it is expected that droplet number concentration, Nd, will increase and droplet size decrease, for a given liquid water path (Twomey 1977), which will greatly affect cloud albedo as smaller droplets reflect more shortwave radiation. However, the magnitude and variability of these processes under different environmental conditions is still uncertain. McComiskey et al.

348

Definition: Phasor Data Concentrator (PDC) | Open Energy Information  

Open Energy Info (EERE)

Phasor Data Concentrator (PDC) Phasor Data Concentrator (PDC) Jump to: navigation, search Dictionary.png Phasor Data Concentrator (PDC) Receives and time-synchronizes phasor data from multiple phasor measurement units (PMUs) to produce a real-time, time-aligned output data stream. A PDC can exchange phasor data with PDCs at other locations. Through use of multiple PDCs, multiple layers of concentration can be implemented within an individual synchrophasor data system.[1] Related Terms smart grid References ↑ https://www.smartgrid.gov/category/technology/phasor_data_concentrator_pdc [[C LikeLike UnlikeLike You like this.Sign Up to see what your friends like. ategory: Smart Grid Definitions|Template:BASEPAGENAME]] Retrieved from "http://en.openei.org/w/index.php?title=Definition:Phasor_Data_Concentrator_(PDC)&oldid=493108"

349

$60 Million to Fund Projects Advancing Concentrating Solar Power |  

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

$60 Million to Fund Projects Advancing Concentrating Solar Power $60 Million to Fund Projects Advancing Concentrating Solar Power $60 Million to Fund Projects Advancing Concentrating Solar Power November 8, 2011 - 10:34am Addthis A 101 video on concentrating solar panel systems. | Courtesy of the Energy Department Jesse Gary Solar Energy Technologies Program On Tuesday, October 25, the Energy Department's SunShot initiative announced a $60 million funding opportunity (FOA) to advance concentrating solar power in the United States. The SunShot program seeks to support research into technologies with potential to dramatically increase efficiency, lower costs, and deliver more reliable performance than existing commercial and near-commercial concentrating solar power (CSP) systems. The Department expects to fund 20 to 22 projects, and we encourage

350

Method and apparatus for concentrating vapors for analysis  

DOE Patents (OSTI)

A pre-concentration device and a method are disclosed for concentrating gaseous vapors for analysis. Vapors sorbed and concentrated within the bed of the pre-concentration device are thermally desorbed, achieving at least partial separation of the vapor mixtures. The pre-concentration device is suitable, e.g., for pre-concentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2012-06-05T23:59:59.000Z

351

NREL: Concentrating Solar Power Research - 10-Megawatt Supercritical...  

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

Supercritical Carbon Dioxide Turbine Test-Thermodynamic Cycle to Revolutionize CSP Systems Advancing concentrating solar power (CSP) systems to the target cost of 0.06...

352

NREL: Concentrating Solar Power Research - Power Block R&D  

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

the potential of advanced power cycles to integrate with concentrating solar power (CSP) systems. This research increases the efficiency and reduces the levelized cost of...

353

SunShot Concentrating Solar Power Program Review 2013 - Instructions...  

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

SunShot Concentrating Solar Power Program Review 2013 April 23-25, 2013 Phoenix, Arizona Skip navigation to main content Menu Home About Agenda Register Venue Presentations...

354

Coal-based Direct Reduction of Iron Concentrate Pellets by ...  

Science Conference Proceedings (OSTI)

Presentation Title, Coal-based Direct Reduction of Iron Concentrate Pellets by Microwave Heating. Author(s), Wang Xia, Huang Zhucheng. On-Site Speaker ...

355

SOLAR THERMAL CONCENTRATOR APPARATUS, SYSTEM, AND METHOD - Energy ...  

SOLAR THERMAL CONCENTRATOR APPARATUS ... The invention was made with the State of California's support under the California Energy Commission contract No. 5005 ...

356

Impact of Heat Transfer Media on Materials for Concentrated Solar ...  

Science Conference Proceedings (OSTI)

Presentation Title, Impact of Heat Transfer Media on Materials for Concentrated Solar Power. Author(s), Dane Wilson. On-Site Speaker (Planned), Dane Wilson.

357

SunShot Concentrating Solar Power Program Review 2013 - Speakers  

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

Solar Power (CSP), Concentrating PV (CPV), as well as run-of-river hydro, geothermal, and biomass power projects. Highlight Presentation Speakers Daniel Chen, Business...

358

Method of trivalent chromium concentration determination by atomic spectrometry  

DOE Patents (OSTI)

A method is disclosed for determining the concentration of trivalent chromium Cr(III) in a sample. The addition of perchloric acid has been found to increase the atomic chromium spectrometric signal due to Cr(III), while leaving the signal due to hexavalent chromium Cr(VI) unchanged. This enables determination of the Cr(III) concentration without pre-concentration or pre-separation from chromium of other valences. The Cr(III) concentration may be measured using atomic absorption spectrometry, atomic emission spectrometry or atomic fluorescence spectrometry.

Reheulishvili, Aleksandre N. (Tbilisi, 0183, GE); Tsibakhashvili, Neli Ya. (Tbilisi, 0101, GE)

2006-12-12T23:59:59.000Z

359

Growth History Of Kilauea Inferred From Volatile Concentrations...  

Open Energy Info (EERE)

Growth History Of Kilauea Inferred From Volatile Concentrations In Submarine-Collected Basalts Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Growth...

360

Modelling Concentrating Solar Power with Thermal Energy Storage...  

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

Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies Marissa Hummon 3 rd International Solar Power Integration Workshop October 20-22, 2013...

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


361

Modular Off-Axis Fiber Optic Solar Concentrator  

interior lighting: Sunlight Direct, ... a Modular Off-Axis Fiber Optic Solar Concentrator, uses novel embodiments of an off-axis aspheric focusing system to achieve ...

362

Concentrating Solar Power: Solar Energy Technologies Program (SETP) (Fact Sheet)  

DOE Green Energy (OSTI)

Fact sheet summarizing the goals and activities of the DOE Solar Energy Technologies Program efforts within its concentrating solar power subprogram.

Not Available

2009-10-01T23:59:59.000Z

363

Human Exposure to Ultrafine Particles-Sources, Concentrations...  

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

Human Exposure to Ultrafine Particles-Sources, Concentrations, Indoor-Outdoor Relationships, and Mitigation Techniques Speaker(s): Lance Wallace Date: July 22, 2013 - 12:00pm -...

364

Concentrating solar power technologies offer utility-scale power ...  

U.S. Energy Information Administration (EIA)

Concentrating solar power (CSP) is a utility-scale renewable energy option for generating electricity that is receiving considerable attention in the southwestern ...

365

Study on the Pelletizing of Pyrite Cinder with Magnetite Concentrate ...  

Science Conference Proceedings (OSTI)

... on the feasibility of pelletizing with magnetite concentrate and the wasted pyrite ... Correlating Long Term Production Life-Cycles in the Materials and Energy ...

366

DOE to Invest $35 Million in Concentrating Solar Power Projects  

DOE to Invest $35 Million in Concentrating Solar Power Projects September 19, 2008. The U.S. Department of Energy (DOE) selected 15 new projects--for ...

367

HYDROGEN CONCENTRATION AND DISTRIBUTION IN HIGH-PURITY GERMANIUM CRYSTALS  

E-Print Network (OSTI)

melting point. By analogy, hydrogen permeation measurementsin silicon suggest that the hydrogen solubility also is notNo. 1, February 1982 HYDROGEN CONCENTRATION AND DISTRIBUTION

Hansen, W.L.

2010-01-01T23:59:59.000Z

368

Carbothermic Reduction of Ilmenite Concentrate with Coke Assisted ...  

Science Conference Proceedings (OSTI)

In this study, the carbothermic reduction behavior of the ilmenite concentrate milled was investigated. It was found that the ball milling method can results a ...

369

Thermoelectrics Combined with Solar Concentration for Electrical and Thermal Cogeneration.  

E-Print Network (OSTI)

??A solar tracker and concentrator was designed and assembled for the purpose of cogeneration of thermal power and electrical power using thermoelectric technology. A BiTe… (more)

Jackson, Philip Robert

2012-01-01T23:59:59.000Z

370

Market concentration and marketing power among electricity generators in Texas  

SciTech Connect

Policy initiatives designed to foster competition among electricity generators in Texas face a special challenge due to the relative isolation of that system. This isolation contributes to high levels of market concentration and market power that could hinder the development of a truly competitive market. This paper examines market concentration and market power in the ERCOT market for electricity generation by calculating the Herfindahl-Hirschman index (HHI) under various assumptions to gauge the degree of market concentration among generators in ERCOT. In addition, some ongoing studies of market power in ERCOT are discussed. The distinction between market concentration and market power is highlighted.

Zarnikau, J.; Lam, A. [Planergy Inc., Austin, TX (United States)

1998-11-01T23:59:59.000Z

371

NREL: Learning - Student Resources on Concentrating Solar Power  

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

and College Level NREL Concentrating Solar Power Research Features information about parabolic troughs, systems-driven modeling and analysis, and other advanced components and...

372

Fluidised Bed Technology for Gold Ore and Gold Concentrate  

Science Conference Proceedings (OSTI)

Presentation Title, Fluidised Bed Technology for Gold Ore and Gold Concentrate. Author(s) ... such as the circulating fluidised bed and the bubbling fluidized bed.

373

SunShot Initiative: Concentrating Solar Power Staff Profiles  

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

Staff Profiles The SunShot Initiative concentrating solar power (CSP) program competitively funds and actively manages the efforts of industry, national laboratories, and...

374

NREL: Concentrating Solar Power Research - Updated Solar Resource...  

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

international activities and work with federal agencies. Printable Version Concentrating Solar Power Research Home Projects Research Staff Working with Us Data & Resources...

375

Reductive Sulfur-fixation Smelting of Stibnite Concentrate in Sodium ...  

Science Conference Proceedings (OSTI)

Abstract Scope, A new process to extracted antimony directly from stibnite concentrate by reductive sulfur-fixation smelting in sodium molten salt has been ...

376

Drivers and Barriers in the Current Concentrated Solar Power...  

Open Energy Info (EERE)

Current Concentrated Solar Power (CSP) Market (Webinar) Focus Area: Solar Topics: Market Analysis Website: www.leonardo-energy.orgwebinar-drivers-and-barriers-current-csp-marke...

377

Techno-economic Appraisal of Concentrating Solar Power Systems (CSP).  

E-Print Network (OSTI)

?? The diffusion of Concentrating Solar Power Systems (CSP) systems is currently taking place at a much slower pace than photovoltaic (PV) power systems. This… (more)

Gasti, Maria

2013-01-01T23:59:59.000Z

378

Impact of Concentrate Feed Temporal Fluctuations on a Copper ...  

Science Conference Proceedings (OSTI)

In all simulated cases, the time-mean concentrate throughput remained constant to .... Reduction Product Separation by Vacuum Distillation in the Process of ...

379

Atmospheric CH4 Concentrations from the CSIRO GASLAB Flask Sampling...  

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

CH4 Concentrations from the CSIRO GASLAB Flask Sampling Network image Alert, NWT, Canada Cape Ferguson, Australia Cape Grim, Australia Estevan Point, BC, Canada Macquarie...

380

Commercial Application of a Photovoltaic Concentrator system. Phase I. Final report, 1 June 1978-28 February 1979  

DOE Green Energy (OSTI)

This report documents the design and analysis of the BDM CAPVC (Commercial Application of a Photovoltaic Concentrator) system. The preliminary design, prototype test and evaluation, system analysis, and final design of a large-scale concentrating photovoltaic system are described. The application is on an attractive new office building which represents a large potential market. The photovoltaic concentrating array is a roof-mounted, single-axis linear parabolic trough, using single crystalline silicon photovoltaic cells. A total of 6720 square feet of aperture is focussed on 13,944 PV cells. The photovoltaic system operates in parallel with the local utility in an augmentary loadsharing operating mode. The array is actively cooled and the thermal energy utilized for building heat during winter months. (WHK)

Anderson, D.J.; Anderson, E.R.; Bardwell, K.M.

1980-04-01T23:59:59.000Z

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


381

Molecular Cell, Volume 37 Supplemental Information  

E-Print Network (OSTI)

a gradual increase in NF-kB p65 nuclear concentration. (A) Wild-type HCT 116 cells were stimulated with increasing doses of TNF for 20 minutes. The nuclear translocation of NF-kB was assessed by immunofluorescence that increasing TNF doses induce uniformly increasing nuclear localization of NF-kB in the cell population. (C) We

Bulyk, Martha L.

382

Equilibrium Conformations of Concentric-tube Continuum Robots  

Science Conference Proceedings (OSTI)

Robots consisting of several concentric, preshaped, elastic tubes can work dexterously in narrow, constrained, and/or winding spaces, as are commonly found in minimally invasive surgery. Previous models of these â??active cannulasâ?ť assume ... Keywords: active cannula, concentric tube robot, continuum robot, elastica, flexible arms, kinematics, mechanics, medical robots, snake-like robot, variational calculus

D. Caleb Rucker; Robert J. Webster, III; Gregory S. Chirikjian; Noah J. Cowan

2010-09-01T23:59:59.000Z

383

SunLab: Concentrating Solar Power Program Overview  

DOE Green Energy (OSTI)

DOE's Concentrating Solar Power (CSP) program is collaborating with its partners in the private sector to develop two new solar technologies -- power towers and dish/engines -- to meet the huge commercial potential for solar power. Concentrating solar power plants produce electric power by first converting the sun's energy into heat, and then to electricity in a conventional generator.

NONE

1998-11-24T23:59:59.000Z

384

Limited Temporal Variability of Arsenic Concentrations in 20 Wells  

E-Print Network (OSTI)

Limited Temporal Variability of Arsenic Concentrations in 20 Wells Monitored for 3 Years switched their water consumption to wells that meet the local standard for As in drinking water of 50 µg if As concentrations in those wells could change over time. To address this issue, we report here precise groundwater

van Geen, Alexander

385

PROCESS FOR THE CONCENTRATION OF ORES CONTAINING GOLD AND URANIUM  

DOE Patents (OSTI)

ABS>A process is described for concentrating certain low grade uranium and gold bearing ores, in which the gangue is mainly quartz. The production of the concentrate is accomplished by subjecting the crushed ore to a froth floatation process using a fatty acid as a collector in conjunction with a potassium amyl xanthate collector. Pine oil is used as the frothing agent.

Gaudin, A.M.; Dasher, J.

1958-06-10T23:59:59.000Z

386

Mirror alignment and focus of point-focus solar concentrators  

DOE Green Energy (OSTI)

Distributed point-focusing solar concentrators are being developed for dish-Stirling systems and other applications. Many of these concentrators make use of faceted mirrors that have to be accurately aligned. Some of the solar concentrator designs use stretched-membrane facets that also require focusing. Accurate mirror alignment and focus of faceted solar concentrators have two benefits. First, the concentration ratio of the concentrator/receiver (collector) system is improved with accurate alignment and focus. The receiver aperture diameter can therefore be smaller, thereby reducing thermal losses from the receiver and improving the overall efficiency of the collector. Second, and perhaps more importantly, flux intensities on the receiver can be sensitive to facet alignment and focus. In this paper, the theory and practical application of an alignment and focusing technique are presented. In the technique, light from an artificial source is reflected from the concentrator`s facets to a target. From basic geometric principles, the shape and location of the reflected light on the target can be predicted. Alignment is accomplished by adjusting the facets aim so that the reflected image falls on the predetermined location. To focus a stretched-membrane facet, the reflected image size is adjusted to match that of the target. The governing equations used to draw the alignment targets are developed and the practical application of the technique to the alignment and focus of the Cummins Power Generation, Inc. CPG-460 are presented. Alignment uncertainty associated with this technique on the CPG-460 is also discussed.

Diver, R.B.

1994-11-01T23:59:59.000Z

387

Survey of Iron and Nickel Concentrations in PWR Primary Coolant  

Science Conference Proceedings (OSTI)

The concentrations of iron and nickel corrosion products in primary coolant water were measured at eleven different pressurized water reactors. Two reactors experienced anomalies in the axial power distribution during the cycles that were sampled. The axial power distribution anomalies appeared to be associated with high-coolant nickel concentrations early in the fuel cycle.

2001-07-27T23:59:59.000Z

388

Estimating Gas Concentration of Coal Mines Based on ISGNN  

Science Conference Proceedings (OSTI)

Online detecting failure of gas sensors in mine wells is an important problem. A key step for solution of the problem is estimating sample values of detected gas sensor, according to sample values of other gas sensors. We propose a scheme based on ISGNN ... Keywords: Estimating gas concentration, Gas concentration modeling, Generating Neural Networks, ISGNN

Aiguo Li; Lina Song

2009-11-01T23:59:59.000Z

389

Effect of Substrate Concentration on Methane Fermentation of Cattle Dung  

Science Conference Proceedings (OSTI)

Methane fermentation of cattle manure (CM) with different total solid contents were conducted in the laboratory-scale batch reactors (2.5 L volume) in order to determine the substrate concentration performance and potential energy recovery at the optimal ... Keywords: Cattle manure, Substrate concentration, Dry fermentation, Wet fermentation, Biogas

Jha Ajay Kumar; He Junguo; Li Jianzheng; Zheng Guocheng

2010-03-01T23:59:59.000Z

390

Freeze Concentration of Dairy Products, Phase Three and Phase Four  

Science Conference Proceedings (OSTI)

Freeze concentration offers substantially increased electricity demand while providing dairy processors with new and improved products. Pilot testing demonstrates the smoother and creamier taste of freeze concentrated milk products. Economic analyses indicate that this technology can produce superior products competitive with state-of-the-art evaporation technology.

2001-03-22T23:59:59.000Z

391

Sustainable Energy Science and Engineering Center Concentrating Collectors  

E-Print Network (OSTI)

reflector; c) Plane receiver with plane reflector; d) parabolic concentrator; e) Fresnel reflector f) Array that are faced at different angles so that light falling on any ring is focused to the same point. Parabolic trough collector: A high-temperature (above 360K) solar thermal concentrator with the capacity

Krothapalli, Anjaneyulu

392

Free Processes via Matrix Theory Concentration week on free Probability  

E-Print Network (OSTI)

Free Processes via Matrix Theory Concentration week on free Probability Texas A&M, July 9-13. Nizar Demni Paris VI University July 10, 2007 Nizar Demni Paris VI University Free Processes via Matrix Theory Concentration week on free Pr #12;Definitions Non commutative probability space : Unital Algebra A + linear

Anshelevich, Michael

393

Optical analysis of semi and compound hyperbolic spiral solar concentrator  

SciTech Connect

In the last few years, considerable efforts have gone into the developments of non-imaging solar concentrators. They are characterized by their moderate concentration ratios (up to 10) and large angle of acceptance which allows the collection of more diffuse radiation as well as direct beam. They have the advantage of high temperature output of focusing concentrators but without diurnal tracking. The most successful one of such concentrator type is the compound parabolic (CPC) which has been extensively studied by numerous investigators. However, it is idealized for the use with flat absorber which suffers from parasitic rear loss and inefficient evacuation for the suppression of convective loss. It has also an over heating problem due to the concentration of solar radiation upon the surface of the absorber in the focal line. In the way of continuous development of the non-imaging concentrators, the authors present here the design and optical analysis of a compound hyperbolic spiral concentrator (CHSC). Its surface of reflection consists of two identical segments of a hyperbolic spiral curve, arranged symmetrical about an axis of symmetry as given. Its optical characterestics are studied and compared with those of the previously discussed HSC which will be designated as semi hyperbolic spiral concentrator (SHSC).

Rabie, L.H.

1983-12-01T23:59:59.000Z

394

Secondary concentrators for parabolic dish solar thermal power systems  

SciTech Connect

One approach to production of electricity or high-temperature process heat from solar energy is to use point-focusing, two-axis pointing concentrators in a distributed-receiver solar thermal system. This paper discusses some of the possibilities and problems in using compound concentrators in parabolic dish systems. 18 refs.

Jaffe, L.D.; Poon, P.T.

1981-01-01T23:59:59.000Z

395

Single element spectral splitting solar concentrator for multiple cells CPV system  

E-Print Network (OSTI)

Shockley Read Hall equation poses a limit to the maximum conversion efficiency of broadband solar radiation attainable by means of a single bandgap converter. A possible approach to overcome such a limit is to convert ...

Stefancich, Marco

396

NUMERICAL ANALYSIS OF DIRECT LIQUID-IMMERSED SOLAR CELL COOLING OF A LINEAR CONCENTRATING PHOTOVOLTAIC RECEIVER  

E-Print Network (OSTI)

performed the best agreement with the experimental data. The Enhanced Wall Function (EWF) model also term in the - equation [14]. The EWF model subdivides the near-wall region into a viscous sub

397

IEA-Technology Roadmap: Concentrating Solar Power | Open Energy Information  

Open Energy Info (EERE)

IEA-Technology Roadmap: Concentrating Solar Power IEA-Technology Roadmap: Concentrating Solar Power Jump to: navigation, search Tool Summary Name: IEA-Technology Roadmap: Concentrating Solar Power Agency/Company /Organization: International Energy Agency Sector: Energy Focus Area: Solar, - Concentrating Solar Power Topics: Implementation, Pathways analysis Resource Type: Guide/manual Website: www.iea.org/papers/2010/csp_roadmap.pdf Cost: Free IEA-Technology Roadmap: Concentrating Solar Power Screenshot References: IEA-CSP Roadmap[1] "This roadmap identifies technology, economy and policy goals and milestones needed to support the development and deployment of CSP, as well as ongoing advanced research in CSF. It also sets out the need for governments to implement strong, balanced policies that favour rapid

398

Energy 101: Concentrating Solar Power | Department of Energy  

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

Energy 101: Concentrating Solar Power Energy 101: Concentrating Solar Power Energy 101: Concentrating Solar Power August 6, 2010 - 12:58pm Addthis Andy Oare Andy Oare Former New Media Strategist, Office of Public Affairs How does it work? Concentrating solar power technologies use mirrors to reflect sunshine, turning it into an intense beam that's collected as heat. Some of the heat is used to produce electricity immediately. The rest is stored so that the generators can provide power for homes and businesses long after the sun has set Whether capturing the sun's heat from towers, dishes, or troughs, concentrating solar power (CSP) technology is making exciting advances. So exciting, in fact, that the federal government is looking at more than 25 square miles in Nevada to demonstrate new CSP technology research.

399

Concentrating Solar Power: Best Practices Handbook for the Collection and  

Open Energy Info (EERE)

Concentrating Solar Power: Best Practices Handbook for the Collection and Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data Jump to: navigation, search Tool Summary LAUNCH TOOL Name: Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data Agency/Company /Organization: National Renewable Energy Laboratory Sector: Energy Focus Area: Solar Topics: Resource assessment, Technology characterizations Resource Type: Dataset, Guide/manual, Lessons learned/best practices Website: www.nrel.gov/docs/fy10osti/47465.pdf Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data Screenshot References: CSP Guide[1] Logo: Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data

400

DOE Statement on Savannah River Site Vitrified Waste Concentrations |  

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

Statement on Savannah River Site Vitrified Waste Concentrations Statement on Savannah River Site Vitrified Waste Concentrations DOE Statement on Savannah River Site Vitrified Waste Concentrations April 30, 2010 - 12:30pm Addthis "The Office of Environmental Management has decided not to move forward at this time with its February decision to direct contractors to start planning for higher concentrations of plutonium in waste canisters at the Savannah River Site. While this may ultimately be a better way to manage and minimize the volume of waste, the Department wants to further review the issues involved before proceeding. No canisters have been filled at the higher concentration level." Addthis Related Articles Energy Secretary Chu Announces $6 Billion in Recovery Act Funding for Environmental Cleanup Department of Energy Projects Win 36 R&D 100 Awards for 2011

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


401

A new trough solar concentrator and its performance analysis  

SciTech Connect

The operation principle and design method of a new trough solar concentrator is presented in this paper. Some important design parameters about the concentrator are analyzed and optimized. Their magnitude ranges are given. Some characteristic parameters about the concentrator are compared with that of the conventional parabolic trough solar concentrator. The factors having influence on the performance of the unit are discussed. It is indicated through the analysis that the new trough solar concentrator can actualize reflection focusing for the sun light using multiple curved surface compound method. It also has the advantages of improving the work performance and environment of high-temperature solar absorber and enhancing the configuration intensity of the reflection surface. (author)

Tao, Tao; Hongfei, Zheng [School of Mechanical and Vehicular, Beijing Institute of Technology, Beijing 100081 (China); Kaiyan, He [School of Physical Science and Technology, Guangxi University, Nanning 530004 (China); Mayere, Abdulkarim [Institute of Sustainable Energy Technology, University of Nottingham, Nottingham NG7 2RD (United Kingdom)

2011-01-15T23:59:59.000Z

402

Concentration-Temperature Superposition of Helix Folding Rates in Gelatin  

E-Print Network (OSTI)

We study the kinetics of helix-coil transition in water solutions of gelatin (collagen protein) by optical rotation techniques combined with thermal characterization. By examining the rates of secondary helix folding, and covering a very wide range of solution concentrations, we are able to identify a universal exponential dependence of folding rate on concentration and quench temperature. We demonstrate a new concentration-temperature superposition of data at all temperatures and concentrations, and build the corresponding master curve. The results support the concept of a diffuse helix-coil transition. We find no concentration dependance of the normalized rate constant, suggesting first order (single) kinetics of secondary helix folding dominate in the early stages of renaturation.

J. L. Gornall; E. M. Terentjev

2006-02-07T23:59:59.000Z

403

Concentrated ion beam emitted from an enlarged cylindrical-anode-layer Hall plasma accelerator and mechanism  

SciTech Connect

An enlarged cylindrical-anode-layer Hall plasma accelerator with an outlet diameter of 150 mm is experimentally demonstrated to produce a concentrated ion beam, especially at a high discharge voltage, with a high current utilization efficiency of up to {approx}0.9. Numerical investigation based on the three-dimensional particle-in-cell method is performed to study the ion dynamics and elucidate the origin of the ion beam characteristics. The simulation results reveal that the equipotential lines play an important role in the surface near the anode emitting the ions. The ion emitting surface is determined by the magnetic field lines near the anode and the magnetic mirror contributes to the concentrated beam significantly. The high current utilization efficiency results from the appropriate obliquity of the magnetic mirror.

Geng, S. F.; Wang, C. X. [Southwestern Institute of Physics, Chengdu 610041 (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Tang, D. L.; Qiu, X. M. [Southwestern Institute of Physics, Chengdu 610041 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2013-01-28T23:59:59.000Z

404

Oxidants, Antioxidants and Cell Signaling  

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

Oxidants, Antioxidants and Cell Signaling Oxidants, Antioxidants and Cell Signaling Speaker(s): Chandan K. Sen Date: February 17, 1998 - 12:00pm Location: 90-3148 Seminar Host/Point of Contact: Richard Sextro Reactive oxygen species represent a common mediator of environmental stress such as during physical exercise, ozone exposure, UV radiation and xenobiotic (pollutant) metabolism. Antioxidant defense systems protect against the ravages of such reactive species. In contrast to the conventional idea that reactive oxygen is mostly a trigger for oxidative damage of biological structures, now we know that low physiologically relevant concentration of reactive oxygen species can regulate a variety of key molecular mechanisms that may be linked with important processes such as immune response, cell-cell adhesion, cell proliferation, inflammation,

405

Breaker concentrations required to improve the permeability of proppant packs damaged by concentrated linear and borate-crosslinked fracturing fluids  

Science Conference Proceedings (OSTI)

This paper reports on the concentrations of an oxidative breaker required to reduce significantly the proppant-pack permeability damage caused by aqueous hydraulic fracturing fluids. Long-term, proppant-pack permeability testing was used to evaluate linear and borate-crosslinked gels. Results indicate that increasing the breaker concentration can reduce proppant-pack permeability damage very effectively.

Brannon, H. (BJ Services (United States)); Pulsinelli, R.J. (Dowell Schlumberger, Tulsa, OK (United States))

1992-11-01T23:59:59.000Z

406

Upper bounds for the yearly energy delivery of stationary solar concentrators and the implications for concentrator optical design  

SciTech Connect

Compound parabolic concentrator (CPC) type collectors have been viewed as the optimal design for totally stationary concentrators. However the CPC is ideal only for uniform incident solar flux averaged over the energy collection period. The actual yearly-averaged incident flux map turns out to be highly non-uniform, as a function of projected incidence angle, which implies that concentration can be increased markedly if optical collection efficiency is compromised. The question then becomes: what concentrator angular acceptance function is best matched to nature`s radiation flux input, and how much energy can such a concentrator deliver? The recently-invented tailored edge-ray concentrator (TERC) approach could be used to determine optimal reflector contours, given the optimal acceptance angle function. We demonstrate that totally stationary TERCs can have around three times the geometric concentration of corresponding optimized stationary CPCs, with greater energy delivery per absorber area, in particular for applications that are currently being considered for stationary evacuated concentrators with the latest low-emissivity selective coating, e.g., solar-driven double-stage absorption chillers (at around 170{degree}C) and solar thermal power generation (at around 250{degree}C). 20 refs., 3 figs., 2 tabs.

Gordon, J.M. [Ben-Gurion Univ. of the Negev, Sede Boqer Campus (Israel)]|[Ben-Gurion Univ. of the Negev, Beersheva (Israel); Lasken, M. [Ben-Gurion Univ. of the Negev, Sede Boqer Campus (Israel); Ries, H. [Paul Scherrer Inst., Villigen (Switzerland)

1996-10-01T23:59:59.000Z

407

High-Efficiency Solar Cells for Large-Scale Electricity Generation  

DOE Green Energy (OSTI)

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

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

2008-09-26T23:59:59.000Z

408

Mercury concentrations in tissues of Florida bald eagles  

Science Conference Proceedings (OSTI)

We collected 48 blood and 61 feather samples from nestling bald eagles at 42 nests and adult feather samples from 20 nests in north and central Florida during 1991-93. We obtained 32 liver, 10 feather, and 5 blood samples from 33 eagle carcasses recovered in Florida during 1987-93. For nestlings, mercury concentrations in blood (GM = 0.16 ppm wet wt) and feather (GM = 3.23 ppm) samples were correlated (r = 0.69, P = 0.0001). Although nestlings had lower mercury concentrations in feathers than did adults (GM = 6.03 ppm), the feather mercury levels in nestlings and adults from the same nest were correlated (r = 0.63, P eagles (GM = 0.23 ppm) was similar to Florida nestlings but some Florida nestlings had blood mercury concentrations up to 0.61 ppm, more than twice as high as captive adults. Feather mercury concentrations in both nestlings and adults exceeded those in captive eagles, but concentrations in all tissues were similar to, or lower than, those in bald eagles from other wild populations. Although mercury concentrations in Florida eagles are below those that cause mortality, they are in the range of concentrations that can cause behavioral changes or reduce reproduction. We recommend periodic monitoring of mercury in Florida bald eagles for early detection of mercury increases before negative effects on reproduction occur. 26 refs., 5 figs., 2 tabs.

Wood, P.B.; Wood, J.M. [Wes Virginia Univ., Morgantown, WV (United States); White, J.H. [Florida Game and Fresh Water Fish Commission, Eustis, FL (United States)] [and others

1996-01-01T23:59:59.000Z

409

Fuel Cell Technologies Office: Fuel Cells  

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

Efficiency and Renewable Energy EERE Home | Programs & Offices | Consumer Information Fuel Cells Search Search Help Fuel Cells EERE Fuel Cell Technologies Office Fuel Cells...

410

On the entanglement concentration of three-partite states  

E-Print Network (OSTI)

We investigate the concentration of multi-party entanglement by focusing on simple family of three-partite pure states, superpositions of Greenberger-Horne-Zeilinger states and singlets. Despite the simplicity of the states, we show that they cannot be reversibly concentrated by the standard entanglement concentration procedure, to which they seem ideally suited. Our results cast doubt on the idea that for each N there might be a finite set of N-party states into which any pure state can be reversibly transformed. We further relate our results to the concept of locking of entanglement of formation.

Berry Groisman; Noah Linden; Sandu Popescu

2005-07-30T23:59:59.000Z

411

Design of photovoltaic central power station concentrator array  

Science Conference Proceedings (OSTI)

A design for a photovoltaic central power station using tracking concentrators has been developed. The 100 MW plant is assumed to be located adjacent to the Saguaro Power Station of Arizona Public Service. The design assumes an advanced Martin Marietta two-axis tracking fresnel lens concentrator. The concentrators are arrayed in 5 MW subfields, each with its own power conditioning unit. The photovoltaic plant output is connected to the existing 115 kV switchyard. The site specific design allows detailed cost estimates for engineering, site preparation, and installation. Collector and power conditioning costs have been treated parametrically.

Not Available

1984-02-01T23:59:59.000Z

412

Natural convective studies within a compound parabolic concentrator enclosure  

SciTech Connect

The contribution due to natural convection within a compound parabolic concentrator enclosure has been experimentally determined. These studies have been conducted within a truncated compound parabolic concentrator having a concentration ratio of 4, a receiver width of 3.175 cm, and a length of 244.0 cm. The receiver was heated electrically while the aperture was provided with a duct that was cooled by water. The limbs of the collector were fabricated from aluminum. Temperatures were directly obtained with copper constantan thermocouples located throughout the entire enclosure and provided the basis needed to calculate the different modes of heat transfer. The constant heat flux

Tatara, R.A.

1983-01-01T23:59:59.000Z

413

Electrochemical separation and concentration of sulfur containing gases from gas mixtures  

DOE Patents (OSTI)

A method of removing sulfur oxides of H.sub.2 S from high temperature gas mixtures (150.degree.-1000.degree. C.) is the subject of the present invention. An electrochemical cell is employed. The cell is provided with inert electrodes and an electrolyte which will provide anions compatible with the sulfur containing anions formed at the anode. The electrolyte is also selected to provide inert stable cations at the temperatures encountered. The gas mixture is passed by the cathode where the sulfur gases are converted to SO.sub.4.sup.= or, in the case of H.sub.2 S, to S.sup.=. The anions migrate to the anode where they are converted to a stable gaseous form at much greater concentration levels (>10X). Current flow may be effected by utilizing an external source of electrical energy or by passing a reducing gas such as hydrogen past the anode.

Winnick, Jack (3805 Woodrail-on-the-Green, Columbia, MO 65201)

1981-01-01T23:59:59.000Z

414

A concentration rebound method for measuring particle penetration and  

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

A concentration rebound method for measuring particle penetration and A concentration rebound method for measuring particle penetration and deposition in the indoor environment Title A concentration rebound method for measuring particle penetration and deposition in the indoor environment Publication Type Journal Article LBNL Report Number LBNL-51631 Year of Publication 2003 Authors Thatcher, Tracy L., Melissa M. Lunden, Kenneth L. Revzan, Richard G. Sextro, and Nancy J. Brown Journal Aerosol Science & Technology Volume 37 Start Page Chapter Pagination 847-864 Abstract Continuous, size resolved particle measurements were performed in two houses in order to determine size- dependent particle penetration into and deposition in the indoor environment. The experiments consisted of three parts: measurement of the particle loss rate following artificial elevation of indoor particle concentrations,

415

An Investigation of Instantaneous Diffusion and Concentration Fluctuations  

Science Conference Proceedings (OSTI)

Instantaneous plume behavior is investigated via experimental and modeling results from a recent field campaign. The data consist of wind velocity and concentration measurements collected 700 m from a point source of sulfur hexafluoride during ...

Holly Peterson; Brian Lamb

1995-12-01T23:59:59.000Z

416

Energy Department Announces New Concentrating Solar Power Technology...  

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

total projects to further advance cutting-edge concentrating solar power technologies (CSP). The awards span 13 states for a total of 56 million over three years, subject to...

417

SunLab: Advancing Concentrating Solar Power Technology  

DOE Green Energy (OSTI)

Concentrating solar power (CSP) technologies, including parabolic troughs, power towers, and dish/engines, have the potential to provide the world with tens of thousands of megawatts of clean, renewable, cost-competitive power.

NONE

1998-11-24T23:59:59.000Z

418

Atmospheric Concentrations of Submicron Contact-freezing Nuclei  

Science Conference Proceedings (OSTI)

Atmospheric concentrations of contact-freezing nuclei were measured using a technique primarily sensitive to submicron aerosol particles. Diffusion and phoretic forces were relied on for the capture of nuclei by supercooled drops of distilled ...

Terry Deshler; Gabor Vali

1992-05-01T23:59:59.000Z

419

Concentrating On California Solar Power | Department of Energy  

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

Concentrating On California Solar Power Concentrating On California Solar Power Concentrating On California Solar Power June 14, 2011 - 4:22pm Addthis Ginny Simmons Ginny Simmons Former Managing Editor for Energy.gov, Office of Public Affairs What will the project do? Combined, the projects are estimated to create nearly 1,800 jobs and enough energy to power more than 100,000 homes. Today, Secretary Chu announced conditional commitments for approximately $2 billion in loan guarantees to two California concentrating solar power plants. The projects are estimated to create nearly 1,800 jobs and will utilize advanced technologies which can help drive down the cost of solar power. The two plants, the Mojave Solar Project in San Bernardino County, California and the Genesis Solar Project in Riverside County, California,

420

Energy Department Announces New Concentrating Solar Power Technology  

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

New Concentrating Solar Power New Concentrating Solar Power Technology Investments to American Industry, Universities Energy Department Announces New Concentrating Solar Power Technology Investments to American Industry, Universities June 13, 2012 - 2:28pm Addthis NEWS MEDIA CONTACT (202) 586-4940 WASHINGTON - Building off investments in innovative solar photovoltaic technologies announced at the SunShot Grand Challenge Summit in Denver, Colorado earlier today, the Energy Department announced new investments for 21 total projects to further advance cutting-edge concentrating solar power technologies (CSP). The awards span 13 states for a total of $56 million over three years, subject to congressional appropriations. The research projects, conducted in partnership with private industry, national

Note: This page contains sample records for the topic "three-junction concentrator cells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


421

SunShot Initiative: Low-Cost, Lightweight Solar Concentrators  

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

Cost, Lightweight Solar Concentrators Cost, Lightweight Solar Concentrators JPL logo Graphic of two dishes, mounted to the ground, that are side-by-side. This graphic shows the JPL/L'Garde lightweight concentrator facets, which are deployed for different configurations. The Jet Propulsion Laboratory (JPL), with funding from the 2012 SunShot Concentrating Solar Power (CSP) R&D FOA, is designing an optimized solar thermal collector structure using a lightweight collector structure capable of lowering structural costs, simplifying installation, and leading to mass-manufacturability. Approach The JPL project seeks to achieve the SunShot Initiative installed cost target of $75/m2 for a solar thermal collector system, as well as SunShot performance targets for optical errors, operations during windy conditions, and lifetime.

422

Mirror Film Company Has 'Concentrated' Plans for Expansion | Department of  

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

Mirror Film Company Has 'Concentrated' Plans for Expansion Mirror Film Company Has 'Concentrated' Plans for Expansion Mirror Film Company Has 'Concentrated' Plans for Expansion September 10, 2010 - 1:19pm Addthis Lorelei Laird Writer, Energy Empowers In concentrating solar power, glass is king-but it's fighting to hold on to its crown. The reflectivity of glass mirrors makes them a great choice for focusing sunlight onto a heat generator. However, the glass mirrors can be expensive and heavy -- reducing their ability to compete with conventional energy sources. ReflecTech Inc. has an option: a silvered polymer-based film that does the same job, but with half the weight and cost. Using that film, the company can make 100,000 square feet of mirror panels per year at its factory in Arvada, Colo. Through an Advanced Manufacturing 48C tax credit through the Recovery Act,

423

SunShot Concentrating Solar Power Program Review 2013 - About...  

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

SunShot Concentrating Solar Power Program Review 2013 April 23-25, 2013 Phoenix, Arizona Skip navigation to main content Menu Home About Agenda Register Venue Presentations About...

424

SunShot Concentrating Solar Power Program Review 2013 - Travel...  

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

SunShot Concentrating Solar Power Program Review 2013 April 23-25, 2013 Phoenix, Arizona Skip navigation to main content Menu Home About Agenda Register Venue Presentations Travel...

425

SunShot Concentrating Solar Power Program Review 2013 - Hotel...  

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

SunShot Concentrating Solar Power Program Review 2013 April 23-25, 2013 Phoenix, Arizona Skip navigation to main content Menu Home About Agenda Register Venue Presentations Hotel...

426

SunShot Concentrating Solar Power Program Review 2013 - Agenda  

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

SunShot Concentrating Solar Power Program Review 2013 April 23-25, 2013 Phoenix, Arizona Skip navigation to main content Menu Home About Agenda Register Venue Presentations Agenda...

427

Total production of uranium concentrate in the United States  

Gasoline and Diesel Fuel Update (EIA)

1. Total production of uranium concentrate in the United States, 1996 - 2nd Quarter 2013 pounds U3O8 Calendar-Year Quarter 1st Quarter 2nd Quarter 3rd Quarter 4th Quarter...

428

Energetics Responses to Increases in Greenhouse Gas Concentration  

Science Conference Proceedings (OSTI)

Increasing greenhouse gas concentrations warm the troposphere. However, it is not clear whether this implies changes in the energetics. To study the energetics responses to CO2 increases, changes in the Lorenz energy cycle (LEC) are evaluated ...

Daniel Hernández-Deckers; Jin-Song von Storch

2010-07-01T23:59:59.000Z

429

Dish/Engine Systems for Concentrating Solar Power  

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

The dish/engine system is a concentrating solar power (CSP) technology that produces relatively small amounts of electricity compared to other CSP technologies—typically in the range of 3 to 25...

430

Characteristics of Maximum Concentrations from Multiple Point Sources  

Science Conference Proceedings (OSTI)

A simple quasi-Newton numerical scheme is applied to determine the hypothetical worst-case meteorology that will result in the maximum combined concentrations at any receptor location in air quality modeling over short distances for multiple ...

N. M. Zoumakis

1998-07-01T23:59:59.000Z

431

On the Relationship between Sulfate and Cloud Droplet Number Concentrations  

Science Conference Proceedings (OSTI)

Comparisons are drawn between the aerosol cloud microphysical theory implicit in the modeling of Kaufman et al. and the cloud droplet and cloud water sulfate concentrations of Leaitch et al. for the purpose of helping to understand the effect of ...

W. R. Leaitch; G. A. Isaac

1994-01-01T23:59:59.000Z

432

Analysis of Concentration Fluctuations from Lidar Observations of Atmospheric Plumes  

Science Conference Proceedings (OSTI)

A series of nearly instantaneous vertical cross sections of power-plant plume concentrations obtained by both airborne and ground-based lidar systems for the Electric Power Research Institute (EPRI) Plume Model Validation and Development Project ...

W. S. Lewellen; R. I. Sykes

1986-08-01T23:59:59.000Z

433

Value of Concentrating Solar Power and Thermal Energy Storage  

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

NREL-TP-6A2-45833 February 2010 The Value of Concentrating Solar Power and Thermal Energy Storage Ramteen Sioshansi The Ohio State University Columbus, Ohio Paul Denholm National...

434

Thermoelectrics Combined with Solar Concentration for Electrical and Thermal Cogeneration  

E-Print Network (OSTI)

a heat engine, such as a steam turbine or sterling enginethese concentrations, a steam turbine achieves roughly 25%ratio can run a steam turbine at 35-50% efficiency, with

Jackson, Philip Robert

2012-01-01T23:59:59.000Z

435

Use of compound parabolic concentrator for solar energy collection  

DOE Green Energy (OSTI)

The joint team of Argonne National Laboratory (ANL) and the University of Chicago is reporting their midyear results of a proof-of-concept investigation of the Compound Parabolic Concentrator (CPC) for solar-energy collection. The CPC is a non-imaging, optical-design concept for maximally concentrating radiant energy onto a receiver. This maximum concentration corresponds to a relative aperture (f/number) of 0.5, which is well beyond the limit for imaging collectors. We have constructed an X3 concentrating flat-plate collector 16 ft/sup 2/ in area. This collector has been tested in a trailer laboratory facility built at ANL. The optical and thermal performance of this collector was in good agreement with theory. We have constructed an X10 collector (8 ft/sup 2/) and started testing. A detailed theoretical study of the optical and thermal characteristics of the CPC design has been performed.

Rabi, A.; Sevcik, V.J.; Giugler, R.M.; Winston, R.

1974-01-01T23:59:59.000Z

436

Energy Basics: Thermal Storage Systems for Concentrating Solar...  

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

Systems for Concentrating Solar Power One challenge facing the widespread use of solar energy is reduced or curtailed energy production when the sun sets or is blocked by clouds....

437

Concentrating Solar Power Dish/Engine System Basics | Department...  

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

technologies-typically in the range of 3 to 25 kilowatts. Dishengine systems use a parabolic dish of mirrors to direct and concentrate sunlight onto a central engine that...

438

Novel materials and devices for sunlight concentrating systems  

Science Conference Proceedings (OSTI)

Photovoltaic conversion under concentrated sunlight is a highly promising technique that could make solar-electric power generation economically competitive with fossil fuel power generation by the mid-1980s. An economic analysis has been performed which ...

H. J. Hovel

1978-03-01T23:59:59.000Z

439

The Boulder, Colorado, Concentric Halo Display of 21 July 1986  

Science Conference Proceedings (OSTI)

An exceptional concentric halo display was observed in Boulder, Colorado, on 21 July 1986. As many as six halos were observed and photographed simultaneously between 1530 and 1945 UTC. Extensive photographic documentation (>100 photographs) ...

Paul J. Neiman

1989-03-01T23:59:59.000Z

440

THE CONCENTRATION AND ACCUMULATION OF RADIOACTIVE PHOSPHORUS BY AN AQUATIC FOOD CHAIN  

SciTech Connect

The food chain consisted of green algae, Ankistrodesmus falcatus var acicularis (A. Br.) West; microcurstaceans, Daphnia magna Straus; and Green Sunfish, Lepomis cyanellus Rafinesque. Differences in concentration and accumulation of radioactive phosphorus due to variations in temperature, radioactive and non-radioactive phosphorus content, and combination of organisms were determined. The average accumulation by all Daphnia at 25 deg C was 2.0 times that at 10 deg C. The Concentration Factor was 1.8 times the 10 deg C value at 25 deg C. The accumulation value for algae at 25 deg C was 2.1 times that at 10 deg C while the Concentration Factor was 3.1 times greater. The data indicate that the presence of algae provided a small increase in the amount of available phosphorus for Daphnia in the first 24 hours. However, over longer periods of time the algae apparently directly and/or indirectly reduced the amount of available phosphorus. The accumulation values for algae ranged from 0.2 to 1937 mu c/gm, and for Daphnia from 0.85 to 574 mu c/gm. The Concentration Factors for algae ranged from 136 to 626,976 and from 286 to 1,002,926 for Daphnia. The data indicate that the amount of P/sup 32/ accumulated and concentrated by Daphnia may be influenced by the surface area available for adsorption of phosphorus. An increase in the number of algae cells increased the surface on which bacteria could grow. It was noted that Green Sunfish acquired the most radioactive phosphorus from a diet of Daphnia and algae, less from Daphnia alone, still less from a diet of algae alone, and none from a non-algae, non-Daphnia diet. It appears that direct and indirect interspeciftc competition may have occurred for phosphorus within the food chain. (auth)

Hoffman, D.A.

1962-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "three-junction concentrator cells" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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441

Predicting the Potential Polychlorinated Biphenyl (PCB) Concentration in Electrical Equipment  

Science Conference Proceedings (OSTI)

Mineral oil-filled transformers and other electrical equipment manufactured before Polychlorinated Biphenyls (PCBs) were banned by the United States Environmental Protection Agency (EPA) in 1978 sometimes contain low concentrations of PCBs. Owners of mineral oil-filled transformers whose PCB concentration is not established are permitted by the EPA to assume these units are PCB-contaminated (50-499 ppm) as long as they remain in use or are stored for reuse. Many owners would benefit from knowing the ...

2012-12-31T23:59:59.000Z

442

Infiltration Effects on Residential Pollutant Concentrations for Continuous  

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

Infiltration Effects on Residential Pollutant Concentrations for Continuous Infiltration Effects on Residential Pollutant Concentrations for Continuous and Intermittent Mechanical Ventilation Approaches Title Infiltration Effects on Residential Pollutant Concentrations for Continuous and Intermittent Mechanical Ventilation Approaches Publication Type Journal Article LBNL Report Number LBNL-3978E Year of Publication 2011 Authors Sherman, Max H., Jennifer M. Logue, and Brett C. Singer Journal HVAC&R Research Volume 17 Issue 2 Pagination 159 Publisher Lawrence Berkeley National Laboratory Keywords resave Abstract The prevailing residential ventilation standard in North America, American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62.2, specifies volumetric airflow requirements as a function of the overall size of the home and the number of bedrooms, assumes a fixed, minimal amount of infiltration, and requires mechanical ventilation to achieve the remainder. The standard allows for infiltration credits and intermittent ventilation patterns that can be shown to provide comparable performance. Whole-house ventilation methods have a substantial effect on time-varying indoor pollutant concentrations. If alternatives specified by Standard 62.2, such as intermittent ventilation, are used, short-term pollutant concentrations could exceed acute health standards even if chronic health standards are met.The authors present a methodology for comparing ASHRAE- and non-ASHRAE-specified ventilation scenarios on relative indoor pollutant concentrations. We use numerical modeling to compare the maximum time-averaged concentrations for acute exposure relevant (1-hour, 8-hour, 24-hour ) and chronic exposure relevant (1-year) time periods for four different ventilation scenarios in six climates with a range of normalized leakage values. The results suggest that long-term concentrations are the most important metric for assessing the effectiveness of whole-house ventilation systems in meeting exposure standards and that, if chronic health exposure standards are met, acute standards will also be met.

443

Concentrating Solar Power Program Technology Overview (Fact Sheet)  

SciTech Connect

Concentrating solar power systems use the heat from the sun's rays to generate electricity. Reflective surfaces concentrate the sun's rays up to 10,000 times to heat a receiver filled with a heat-exchange fluid, such as oil. The heated fluid is then used to generate electricity in a steam turbine or heat engine. Mechanical drives slowly turn the reflective surfaces during the day to keep the solar radiation focused on the receiver.

Not Available

2001-04-01T23:59:59.000Z

444

Proceedings of the solar thermal concentrating collector technology symposium  

DOE Green Energy (OSTI)

The purpose of the symposium was to review the current status of the concentrating collector technology, to disseminate the information gained from experience in operating solar systems, and to highlight the significant areas of technology development that must be vigorously pursued to foster early commercialization of concentrating solar collectors. Separate abstracts were prepared for thirteen invited papers and working group summaries. Two papers were previously abstracted for EDB.

Gupta, B.P.; Kreith, F. (eds.) [eds.

1978-08-01T23:59:59.000Z

445

Evaluation tests for photovoltaic concentrator receiver sections and modules  

DOE Green Energy (OSTI)

Sandia has developed a third-generation set of specifications for performance and reliability testing of photovoltaic concentrator modules. Several new requirements have been defined. The primary purpose of the tests is to screen new concentrator designs and new production runs for susceptibility to known failure mechanisms. Ultraviolet radiation testing of materials precedes receiver section and module performance and environmental tests. The specifications include the purpose, procedure, and requirements for each test. Recommendations for future improvements are presented.

Woodworth, J.R.; Whipple, M.L.

1992-06-01T23:59:59.000Z

446

Optimal Heat Collection Element Shapes for Parabolic Trough Concentrators  

DOE Green Energy (OSTI)

For nearly 150 years, the cross section of the heat collection tubes used at the focus of parabolic trough solar concentrators has been circular. This type of tube is obviously simple and easily fabricated, but it is not optimal. It is shown in this article that the optimal shape, assuming a perfect parabolic figure for the concentrating mirror, is instead oblong, and is approximately given by a pair of facing parabolic segments.

Bennett, C

2007-11-15T23:59:59.000Z

447

Electrodiffusive model for astrocytic and neuronal ion concentration dynamics  

E-Print Network (OSTI)

Electrical neural signalling typically takes place at the time-scale of milliseconds, and is typically modeled using the cable equation. This is a good approximation for processes when ionic concentrations vary little during the time course of a simulation. During periods of intense neural signalling, however, the local extracellular K+ concentration may increase by several millimolars. Clearance of excess K+ likely depends partly on diffusion in the extracellular space, partly on local uptake by- and intracellular transport within astrocytes. This process takes place at the time scale of seconds, and can not be modeled accurately without accounting for the spatiotemporal variations in ion concentrations. The work presented here consists of two main parts: First, we developed a general electrodiffusive formalism for modeling ion concentration dynamics in a one-dimensional geometry, including both an intra- and extracellular domain. The formalism was based on the Nernst-Planck equations. It ensures (i) consistency between the membrane potential and ion concentrations, (ii) global particle/charge conservation, and (iii) accounts for diffusion and concentration dependent variations in resistivities. Second, we applied the formalism to model how astrocytes exchange ions with the ECS, and identified the key astrocytic mechanisms involved in K+ removal from high concentration regions. We found that a local increase in extracellular K\\textsuperscript{+} evoked a local depolarization of the astrocyte membrane, which at the same time (i) increased the local astrocytic uptake of K\\textsuperscript{+}, (ii) suppressed extracellular transport of K+, (iii) increased transport of K+ within astrocytes, and (iv) facilitated astrocytic relase of K+ in extracellular low concentration regions. In summary, these mechanisms seem optimal for shielding the extracellular space from excess K+.

Geir Halnes; Ivar Řstby; Klas H. Pettersen; Stig W. Omholt; Gaute T. Einevoll

2013-04-29T23:59:59.000Z

448

Concentric core optical fiber with multiple-mode signal transmission  

DOE Patents (OSTI)

A concentric core optical fiber provides for the simultaneous but independent transmission of signals over a single optical fiber. The concentric optical fiber is constructed of a single-mode or multimode inner optical fiber defined by a core and a cladding of a lower index of refraction than the core and an outer optical fiber defined by additional cladding concentrically disposed around the cladding and of an index of refraction lower than the first mentioned cladding whereby the latter functions as the core of the outer optical fiber. By employing such an optical fiber construction with a single-mode inner core or optical fiber, highly sensitive interferometric and stable less sensitive amplitude based sensors can be placed along the same length of a concentric core optical fiber. Also, by employing the concentric core optical fiber secure telecommunications can be achieved via the inner optical fiber since an intrusion of the concentric optical fiber will first cause a variation in the light being transmitted through the outer optical fiber and this variation of light being used to trigger a suitable alarm indicative of the intrusion. 3 figs.

Muhs, J.D.

1997-05-06T23:59:59.000Z

449

Concentric core optical fiber with multiple-mode signal transmission  

DOE Patents (OSTI)

A concentric core optical fiber provides for the simultaneous but independent transmission of signals over a single optical fiber. The concentric optical fiber is constructed of a single-mode or multimode inner optical fiber defined by a core and a cladding of a lower index of refraction than the core and an outer optical fiber defined by additional cladding concentrically disposed around the cladding and of an index of refraction lower than the first mentioned cladding whereby the latter functions as the core of the outer optical fiber. By employing such an optical fiber construction with a single-mode inner core or optical fiber, highly sensitive interferometric and stable less sensitive amplitude based sensors can be placed along the same length of a concentric core optical fiber. Also, by employing the concentric core optical fiber secure telecommunications can be achieved via the inner optical fiber since an intrusion of the concentric optical fiber will first cause a variation in the light being transmitted through the outer optical fiber and this variation of light being used to trigger a suitable alarm indicative of the intrusion.

Muhs, Jeffrey D. (Lenoir City, TN)

1997-01-01T23:59:59.000Z

450

50 kWp Photovoltaic Concentrator Application Experiment, Phase I. Final report, 1 June 1978-28 February 1979  

DOE Green Energy (OSTI)

This program consists of a design study and component development for an experimental 50-kWp photovoltaic concentrator system to supply power to the San Ramon substation of the Pacific Gas and Electric Company. The photovoltaic system is optimized to produce peaking power to relieve the air conditioning load on the PG and E system during summer afternoons; and would therefore displace oil-fired power generation capacity. No electrical storage is required. The experiment would use GaAs concentrator cells with point-focus fresnel lenses operating at 400X, in independent tracking arrays of 440 cells each, generating 3.8 kWp. Fourteen arrays, each 9 feet by 33 feet, are connected electrically in series to generate the 50 kWp. The high conversion efficiency possible with GaAs concentrator cells results in a projected annual average system efficiency (AC electric power output to sunlight input) of better than 15%. The capability of GaAs cells for high temperature operation made possible the design of a total energy option, whereby thermal power from selected arrays could be used to heat and cool the control center for the installation. System design and analysis, fabrication and installation, environmental assessment, and cost projections are described in detail. (WHK)

Maget, H.J.R.

1979-06-15T23:59:59.000Z

451

Fuel Cells  

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

Fuel Cells Fuel Cells Converting chemical energy of hydrogenated fuels into electricity Project Description Invented in 1839, fuels cells powered the Gemini and Apollo space missions, as well as the space shuttle. Although fuel cells have been successfully used in such applications, they have proven difficult to make more cost-effective and durable for commercial applications, particularly for the rigors of daily transportation. Since the 1970s, scientists at Los Alamos have managed to make various scientific breakthroughs that have contributed to the development of modern fuel cell systems. Specific efforts include the following: * Finding alternative and more cost-effective catalysts than platinum. * Enhancing the durability of fuel cells by developing advanced materials and

452

Fuel Cells  

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

Fuel Cells Fuel Cells The Solid State Energy Conversion Alliance (SECA) program is responsible for coordinating Federal efforts to facilitate development of a commercially relevant and robust solid oxide fuel cell (SOFC) system. Specific objectives include achieving an efficiency of greater than 60 percent, meeting a stack cost target of $175 per kW, and demonstrating lifetime performance degradation of less than 0.2 percent per

453

Fuel Cells  

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

Fuel cells are an emerging technology that can provide heat and electricity for buildings and electrical power for vehicles and electronic devices.

454

Electrochemical cell  

Science Conference Proceedings (OSTI)

An electrochemical cell is disclosed that has a lithium anode, a thionyl chloride depolarizer and a sulphur dioxide passivation control agent which further includes having the pressure relieved to substantially reduce the internal pressure of the cell. The internal cell pressure is relieved by venting for sufficient time at an elevated temperature to reduce the internal cell pressure to less than five psi at room temperature, preferably by a plurality of venting cycles and a temperature ranging from room temperature to the elevated temperature. Normally, the elevated temperature ranges from at least 100/sup 0/ to greater than 150/sup 0/ F.

Chua, D.L.; Garoutte, K.F.; Levy, L.L.

1982-11-23T23:59:59.000Z

455

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network (OSTI)

PHASE CHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLARChange Materials for Thermal Energy Storage in ConcentratedChange Materials for Thermal Energy Storage in Concentrated

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

456

Phase Change Materials for Thermal Energy Storage in Concentrated Solar Thermal Power Plants  

E-Print Network (OSTI)

PHASE CHANGE THERMAL ENERGY STORAGE FOR CONCENTRATING SOLARMaterials for Thermal Energy Storage in Concentrated SolarMaterials for Thermal Energy Storage in Concentrated Solar

Hardin, Corey Lee

2011-01-01T23:59:59.000Z

457

Airborne concentrations of asbestos in 71 school buildings  

Science Conference Proceedings (OSTI)

A total of 473 air samples from 71 schools scheduled for abatement (328 indoor static samples, 51 personal samples, and 94 outdoor samples) were analyzed by transmission electron microscopy techniques. Six measures of asbestos-in-air concentration were considered: (1) total asbestos structures per cubic centimeter: (2) chrysotile structures per cubic centimeter; (3) amphibole structures per cubic centimeter; (4) structures per cubic centimeter at least 0.5 micron long and at least five times wide; (5) structures per cubic centimeter at least 5 microns long; and (6) structures per cubic centimeter at least 5 microns long and at least 0.2 micron wide. The average concentration of chrysotile structures in indoor air samples was 0.017 structures/cm{sup 3}; the average concentration of amphibole structures was 0.0015 structure/cm{sup 3}. Ninety-five percent of structures found were chrysotile. The average concentrations of all structures were significantly higher indoors than outdoors (P less than 0.001). The average concentration of structures more than 5 microns long indoors was 0.00023 structure/cm{sup 3}. None of the following factors were significantly correlated with asbestos concentrations in air: type of asbestos-containing materials (ACM) present, condition of ACM, accessibility of ACM to students, whether ACM were covered, air flow, or whether sweeping was noted during sample collection. In addition, asbestos-in-air concentrations were not significantly different in different types of schools (high, intermediate or elementary) or in schools constructed in different time periods. Lastly, there was no correlation between the mineral type of asbestos found in the air and the type found in samples of bulk material.

Corn, M.; Crump, K.; Farrar, D.B.; Lee, R.J.; McFee, D.R. (Johns Hopkins Univ., Baltimore, MD (USA))

1991-02-01T23:59:59.000Z

458

Nonimaging concentrators for solar thermal energy. Final report  

DOE Green Energy (OSTI)

A small experimental solar collector test facility has been established on the campus of the University of Chicago. This capability has been used to explore applications of nonimaging optics for solar thermal concentration in three substantially different configurations: (1) a single stage system with moderate concentration on an evacuated absorber (a 5.25X evacuated tube Compound Parabolic Concentrator or CPC), (2) a two stage system with high concentration and a non-evacuated absorber (a 16X Fresnel lens/CPC type mirror) and (3) moderate concentration single stage systems with non-evacuated absorbers for lower temperature (a 3X and a 6.5X CPC). Prototypes of each of these systems have been designed, built and tested. The performance characteristics are presented. In addition a 73 m/sup 2/ experimental array of 3X non-evacuated CPC's has been installed in a school heating system on the Navajo Indian Reservation in New Mexico. The full array has a peak noon time efficiency of approx. 50% at ..delta..T = 50/sup 0/C above ambient and has supplied about half the school's heat load for the past two heating seasons. Several theoretical features of nonimaging concentration have been investigated including their long term energy collecting behavior. The measured performance of the different systems shows clearly that non-tracking concentrators can provide solar thermal energy from moderately high low temperature regimes (> 50/sup 0/C above ambient) up into the mid-temperature region (well above 200/sup 0/C above ambient). The measured efficiency at 220/sup 0/C for the 5.25X CPC was as high or higher than that for any of the commercial tracking systems tested.

Winston, R.

1980-03-21T23:59:59.000Z

459

Fuel Cell Technologies Office: Fuel Cell Animation  

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

Fuel Cell Animation to someone by E-mail Share Fuel Cell Technologies Office: Fuel Cell Animation on Facebook Tweet about Fuel Cell Technologies Office: Fuel Cell Animation on...

460

STATEMENT OF CONSIDERATIONS REQUEST BY EMCORE CORPORATION FOR AN ADVANCE WAIVER OF  

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

EMCORE CORPORATION FOR AN ADVANCE WAIVER OF EMCORE CORPORATION FOR AN ADVANCE WAIVER OF PATENT RIGHTS UNDER SUBCONTRACT NO. NREL-NAT-02-30620-03 ENTITLED "THREE-JUNCTION SOLAR CELL FOR HIGH CONCENTRATION APPLICATIONS" UNDER DOE PRIME CONTRACT NO. DE-FC36-83CH10093; W(A)-02-043; CH-1119 As set out in the attached waiver petition, and in subsequent discussions with DOE Patent Counsel, EMCORE Corporation (EMCORE) has requested an advance waiver of domestic and foreign patent rights for all subject inventions made under the above-identified subcontract by its employees and its subcontractors' employees, regardless of tier, except for inventions made by subcontractors eligible to retain title to inventions pursuant to P.L. 96-517, as amended, and National Laboratories. Referring to item 2 of EMCORE's petition, the purpose of this subcontract is to develop

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


461

Stable, concentrated solutions of polyaniline using amines as gel inhibitors  

DOE Patents (OSTI)

Stable, concentrated solutions of high-molecular weight polyaniline using amines as gel inhibitors. Certain amine compounds (gel inhibitors) are used to form highly concentrated, stable solutions of the emeraldine base form of polyaniline in numerous organic solvents from which coatings, films and fibers are readily prepared without problems associated with rapid gelation which occurs when concentrated solutions are attempted without the use of the gel inhibitors of the present invention. Tertiary amines are used to solubilize low-molecular weight fractions (M.sub.w <120,000, M.sub.n <30,000) of the pernigraniline, emeraldine, and leucoemeraldine oxidation states of polyaniline as concentrated (>20 wt. %) polyaniline solutions, while primary and secondary amines are used to produce solutions having 15-40 wt % of high-molecular weight polyaniline [M.sub.w.gtoreq.120,000, M.sub.n.gtoreq.30,000]. Concentrated solutions of polyaniline co-polymers or ring and/or nitrogen-substituted polyanilines may also be prepared.

Wang, Hsing-Lin (Los Alamos, NM); Mattes, Benjamin R. (Tesuque, NM)

2002-01-01T23:59:59.000Z

462

Development and testing of Parabolic Dish Concentrator No. 1  

DOE Green Energy (OSTI)

Parabolic Dish Concentrator No. 1 (PDC-1) is a 12-m-diameter prototype concentrator that evolved from a six-year effort to produce a unit with low life-cycle costs for use with thermal-to-electric energy conversion devices. The concentrator assembly features panels made of a resin transfer molded balsa core/fiberglass sandwich with plastic reflective film as the reflective surface and a ribbed framework to hold the panels in place. The concentrator assembly tracks in azimuth and elevation on a base frame riding on a circular track. In 1982, PDC-1 was installed at the Jet Propulsion Laboratory's Parabolic Dish Test Site at Edwards Air Force Base, California. Initial optical testing showed that the panels did not exhibit the proper parabolic contour. After reassembly to correct this problem, further optical testing discovered thermal gradients in the panels with daily temperature changes. In spite of this, PDC-1 has sufficient optical quality to operate satisfactorily in a dish-electric system. With suggested improvements, its performance could be increased. The PDC-1 development effort provided the impetus for creating innovative optical testing methods and also provided valuable information for use in designing and fabricating concentrators of future dish-electric systems.

Dennison, E.W.; Thostesen, T.O.

1984-12-15T23:59:59.000Z

463

Concentrating Solar Panels: Bringing the Highest Power and Lowest Cost to the Rooftop  

DOE Green Energy (OSTI)

Soliant Energy is a venture-capital-backed startup focused on bringing advanced concentrating solar panels to market. Our fundamental innovation is that we are the first company to develop a racking solar concentrator specifically for commercial rooftop applications, resulting in the lowest LCOE for rooftop electricity generation. Today, the commercial rooftop segment is the largest and fastest-growing market in the solar industry. Our concentrating panels can make a major contribution to the SAI's objectives: reducing the cost of solar electricity and rapidly deploying capacity. Our commercialization focus was re-shaped in 2009, shifting from an emphasis solely on panel efficiency to LCOE. Since the inception of the SAI program, LCOE has become the de facto standard for comparing commercial photovoltaic systems. While estimation and prediction models still differ, the emergence of performance-based incentive (PBI) and feed-in tariff (FIT) systems, as well as power purchase agreement (PPA) financing structures make LCOE the natural metric for photovoltaic systems. Soliant Energy has designed and demonstrated lower-cost, higher-power solar panels that consists of 6 (500X) PV module assemblies utilizing multi-junction cells and an integrated two-axis tracker. In addition, we have designed and demonstrated a prototype 1000X panel assembly with 8. Cost reductions relative to conventional flat panel PV systems were realized by (1) reducing the amount of costly semiconductor material and (2) developing strategies and processes to reduce the manufacturing costs of the entire system. Performance gains against conventional benchmarks were realized with (1) two-axis tracking and (2) higher-efficiency multi-junction PV cells capable of operating at a solar concentration ratio of 1000X (1000 kW/m2). The program objectives are: (1) Develop a tracking/concentrating solar module that has the same geometric form factor as a conventional flat, roof mounted photovoltaic (PV) panel - the Soliant module will produce more power and cost less than conventional panels of the same size; (2) Target LCOE: $0.079/kWh in 2010; (3) Target efficiency - 26% in 2010 (22% for 2008 prototype, 24% for 2009 pilot); and (4) Target performance - equivalent to 650Wp in 2010 (490W for 2008 prototype, 540W for 2009 pilot).

Michael Deck; Rick Russell

2010-01-05T23:59:59.000Z

464

Fuel Cells  

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

Materials Science » Materials Science » Fuel Cells Fuel Cells Research into alternative forms of energy, especially energy security, is one of the major national security imperatives of this century. Get Expertise Melissa Fox Applied Energy Email Catherine Padro Sensors & Electrochemical Devices Email Fernando Garzon Sensors & Electrochemical Devices Email Piotr Zelenay Sensors & Electrochemical Devices Email Rod Borup Sensors & Electrochemical Devices Email Karen E. Kippen Experimental Physical Sciences Email Like a battery, a fuel cell consists of two electrodes separated by an electrolyte-in polymer electrolyte fuel cells, the separator is made of a thin polymeric membrane. Unlike a battery, a fuel cell does not need recharging-it continues to produce electricity as long as fuel flows

465

Development and fabrication of advanced cover glass for a GaAs solar cell  

DOE Green Energy (OSTI)

This report summarizes work on improving solar cell conversion efficiencies by modifying the cell cover glass. Two approaches were investigated during the course of this work: grooved cover glasses to reduce the effect of top contact obscuration and secondary concentrators to improve concentrator solar cell performances in tracking modules. The grooved cover glass work used an array of metallized V shaped grooves in a thin cover glass (plastic) window to deflect incident light rays away from solar cell front surface regions covered by the solar cell electrical contact metallization onto unobstructed, optically active regions of the solar cell. Secondary concentrators are being considered for use on concentrator solar cells to improve overall system conversion efficiency and reduce receiver module cost. Secondary concentrators designed and fabricated during this project consist of small glass cones to attach directly to the top of the receiver solar cell. When appropriately designed, these secondary concentrator glass cones increase sunlight concentration on the solar cell, improve solar flux uniformity on the cell, improve system tolerance to tracking error, and allow for concentration ratios greater than can be ordinarily achieved with acrylic Fresnel lenses.

Borden, P.G.; Kaminar, N.R.; Grounner, M.

1984-01-01T23:59:59.000Z

466

SunShot Initiative: Baseload Concentrating Solar Power Generation  

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

Concentrating Solar Power Generation Concentrating Solar Power Generation In 2010, DOE issued the Baseload Concentrating Solar Power (CSP) Generation funding opportunity announcement (FOA). The following projects were selected under this competitive solicitation: Abengoa: Advanced Nitrate Salt Central Receiver Power Plant eSolar: Modular and Scalable Baseload Molten Salt Plant Conceptual Design and Feasibility General Atomics: Baseload CSP Generation Integrated with Sulfur-Based Thermochemical Heat Storage HiTek: Low-Cost Heliostat Development Infinia: Innovative Phase Change Thermal Energy Storage Solution for Baseload Power PPG: Next-Generation Low-Cost Reflector Rocketdyne: Solar Power Tower Improvements with the Potential to Reduce Costs SENER: High-Efficiency Thermal Storage System for Solar Plants

467

NREL: Concentrating Solar Power Research - Working with Us  

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

Working with Us Working with Us NREL's interaction with industrial, university, and government partners is the key to moving advanced concentrating solar power technologies into the marketplace and the U.S. economy. We provide opportunities to develop technology partnerships, license our technology, and use our facilities. Developing Technology Partnerships NREL offers a variety of technology partnership agreements to help you gain access to our research expertise in concentrating solar power, including our laboratory and modeling and analysis capabilities. You can: Work collaboratively with us on a concentrating solar power research project through a Cooperative Research and Development Agreement Pay NREL to conduct research without your collaboration through a Work-for-Others agreement.

468

Atmospheric Concentrations of CO2 from Mauna Loa, Hawaii  

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

Atmospheric Concentrations of CO2 from Mauna Loa, Hawaii Atmospheric Concentrations of CO2 from Mauna Loa, Hawaii The graphs on this page are generated from data taken from "Trends in Carbon Dioxide" page on the Department of Commerce/National Oceanic and Atmospheric Administration (NOAA) website. The NOAA website presents monthly and weekly atmospheric CO2 concentrations measured at the Mauna Loa Observatory in Hawaii. It offers weekly and monthly data, additional graphs, analysis, descriptions of how the data are collected, and an animation of historical changes in atmospheric CO2. Mauna Loa constitutes the longest record of direct measurements of CO2 in the atmosphere. The measurents were started by C. David Keeling of the Scripps Institution of Oceanography in March of 1958. Recent Monthly Average CO2

469

Globally Averaged Atmospheric CFC-11 Concentrations: Monthly and Annual  

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

Chlorofluorocarbons » Chlorofluorocarbons » Atmospheric CFC-11 Concentrations Globally Averaged Atmospheric CFC-11 Concentrations: Monthly and Annual Data for the Period 1975-1992 DOI: 10.3334/CDIAC/atg.db1010 data Data (DB1010) Investigator M. A. K. Khalil and R. A. Rasmussen Description This data set presents globally averaged atmospheric concentrations of chlorofluorocarbon 11, known also as CFC-11 or F-11 (chemical name: trichlorofluoromethane; formula: CCl3F). The monthly global average data are derived from flask air samples collected at eight sites in six locations over the period August 1980-July 1992. The sites are Barrow (Alaska), Cape Meares (Oregon), Cape Kumukahi and Mauna Loa (Hawaii), Cape Matatula (American Samoa), Cape Grim (Tasmania), Palmer Station, and the

470

Growth History Of Kilauea Inferred From Volatile Concentrations In  

Open Energy Info (EERE)

History Of Kilauea Inferred From Volatile Concentrations In History Of Kilauea Inferred From Volatile Concentrations In Submarine-Collected Basalts Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Growth History Of Kilauea Inferred From Volatile Concentrations In Submarine-Collected Basalts Details Activities (4) Areas (2) Regions (0) Abstract: Major-element and volatile (H2O, CO2, S) compositions of glasses from the submarine flanks of Kilauea Volcano record its growth from pre-shield into tholeiite shield-stage. Pillow lavas of mildly alkalic basalt at 2600-1900 mbsl on the upper slope of the south flank are an intermediate link between deeper alkalic volcaniclastics and the modern tholeiite shield. Lava clast glasses from the west flank of Papau Seamount are subaerial Mauna Loa-like tholeiite and mark the contact between the two

471

Design of light concentrators for Cherenkov telescope observatories  

E-Print Network (OSTI)

The Cherenkov Telescope Array (CTA) will be the largest cosmic gamma ray detector ever built in the world. It will be installed at two different sites in the North and South hemispheres and should be operational for about 30 years. In order to cover the desired energy range, the CTA is composed of typically 50-100 collecting telescopes of various sizes (from 6 to 24-m diameters). Most of them are equipped with a focal plane camera consisting of 1500 to 2000 Photomultipliers (PM) equipped with light concentrating optics, whose double function is to maximize the amount of Cherenkov light detected by the photo-sensors, and to block any stray light originating from the terrestrial environment. Two different optical solutions have been designed, respectively based on a Compound Parabolic Concentrator (CPC), and on a purely dioptric concentrating lens. In this communication are described the technical specifications, optical designs and performance of the different solutions envisioned for all these light concentra...

Hénault, F; jocou, L; Khélifi, B; Manigot, P; Hormigos, S; Knodlseder, J; Olive, J F; Jean, P; Punch, M

2013-01-01T23:59:59.000Z

472

Concentric micro-nebulizer for direct sample insertion  

DOE Patents (OSTI)

A concentric micro-nebulizer and method for introducing liquid samples into a plasma established in a plasma torch including a first tube connected to a source of plasma gas. The concentric micro-nebulizer has inner and outer concentric tubes extending upwardly within the torch for connection to a source of nebulizer gas and to a source of liquid solvent and to a source of sample liquid. The inner tube is connected to the source of liquid solvent and to the source of sample liquid and the outer tube is connected to the source of nebulizer gas. The outer tube has an orifice positioned slightly below the plasma when it is established, with the inner and outer tubes forming an annulus therebetween with the annular spacing between the tubes at said orifice being less than about 0.05mm. The dead volume of the inner tube is less than about 5 microliters.

Fassel, V.A.; Rice, G.W.; Lawrence, K.E.

1984-03-06T23:59:59.000Z

473

Determination of waterborne {sup 222}Rn concentrations using AC canisters  

SciTech Connect

A method for measuring {sup 222}Rn concentration in water using charcoal canisters is presented. {sup 222}Rn is transferred within a few minutes from water contained in a 0.720 L bottle to a charcoal canister using a portable degassing unit. In the laboratory, gamma counting is performed at least 10 h after sampling to determine waterborne {sup 222}Rn concentration. The results obtained with charcoal canisters are compared to measurements made with Marinelli beakers calibrated in a comparison with liquid scintillation counting. The efficiency of transferring dissolved {sup 222}Rn in water to activated charcoal is 99% based on measurements made using Marinelli beakers. The lower limit of detection at the 95% confidence level is approximately 1 kBq m{sup -3} for a 15 min gamma count. the system was used to measure radon concentration in mineral groundwater near Rome. 7 refs., 1 fig., 1 tab.

Mancini, C.; Giannelli, G. [Dipartimento di Ingegneria Nucleare e Conversioni di Energia, Roma (Italy)

1995-09-01T23:59:59.000Z

474

Wide-range radioactive-gas-concentration detector  

DOE Patents (OSTI)

A wide-range radioactive-gas-concentration detector and monitor capable of measuring radioactive-gas concentrations over a range of eight orders of magnitude is described. The device is designed to have an ionization chamber sufficiently small to give a fast response time for measuring radioactive gases but sufficiently large to provide accurate readings at low concentration levels. Closely spaced parallel-plate grids provide a uniform electric field in the active region to improve the accuracy of measurements and reduce ion migration time so as to virtually eliminate errors due to ion recombination. The parallel-plate grids are fabricated with a minimal surface area to reduce the effects of contamination resulting from absorption of contaminating materials on the surface of the grids. Additionally, the ionization-chamber wall is spaced a sufficient distance from the active region of the ionization chamber to minimize contamination effects.

Anderson, D.F.

1981-11-16T23:59:59.000Z

475

Automobile proximity and indoor residential concentrations of BTEX and MTBE  

Science Conference Proceedings (OSTI)

Attached garages have been identified as important sources of indoor residential air pollution. However, the literature lacks information on how the proximity of cars to the living area affects indoor concentrations of gasoline-related compounds, and the origin of these pollutants. We analyzed data from the Relationships of Indoor, Outdoor, and Personal Air (RIOPA) study and evaluated 114 residences with cars in an attached garage, detached garage or carport, or without cars. Results indicate that homes with cars in attached garages were affected the most. Concentrations in homes with cars in detached garages and residences without cars were similar. The contribution from gasoline-related sources to indoor benzene and MTBE concentrations appeared to be dominated by car exhaust, or a combination of tailpipe and gasoline vapor emissions. Residing in a home with an attached garage could lead to benzene exposures ten times higher than exposures from commuting in heavy traffic.

Corsi, Dr. Richard [University of Texas, Austin; Morandi, Dr. Maria [University of Texas Health Science Center, Houston; Siegel, Dr. Jeffrey [University of Texas, Austin; Hun, Diana E [ORNL

2011-01-01T23:59:59.000Z

476

Concentration and separation of biological organisms by ultrafiltration and dielectrophoresis  

DOE Patents (OSTI)

Disclosed is a method for monitoring sources of public water supply for a variety of pathogens by using a combination of ultrafiltration techniques together dielectrophoretic separation techniques. Because water-borne pathogens, whether present due to "natural" contamination or intentional introduction, would likely be present in drinking water at low concentrations when samples are collected for monitoring or outbreak investigations, an approach is needed to quickly and efficiently concentrate and separate particles such as viruses, bacteria, and parasites in large volumes of water (e.g., 100 L or more) while simultaneously reducing the sample volume to levels sufficient for detecting low concentrations of microbes (e.g., <10 mL). The technique is also designed to screen the separated microbes based on specific conductivity and size.

Simmons, Blake A. (San Francisco, CA); Hill, Vincent R. (Decatur, GA); Fintschenko, Yolanda (Livermore, CA); Cummings, Eric B. (Livermore, CA)

2010-10-12T23:59:59.000Z

477

Separation and concentration of lower alcohols from dilute aqueous solutions  

DOE Patents (OSTI)

A process for producing, from a dilute aqueous solution of a lower (C.sub.1 -C.sub.5) alcohol, a concentrated liquid solution of the alcohol in an aromatic organic solvent is disclosed. Most of the water is removed from the dilute aqueous solution of alcohol by chilling sufficiently to form ice crystals. Simultaneously, the remaining liquid is extracted at substantially the same low temperature with a liquid organic solvent that is substantially immiscible in aqueous liquids and has an affinity for the alcohol at that temperature, causing the alcohol to transfer to the organic phase. After separating the organic liquid from the ice crystals, the organic liquid can be distilled to enrich the concentration of alcohol therein. Ethanol so separated from water and concentrated in an organic solvent such as toluene is useful as an anti-knock additive for gasoline.

Moore, Raymond H. (Richland, WA); Eakin, David E. (Kennewick, WA); Baker, Eddie G. (Richland, WA); Hallen, Richard T. (Richland, WA)

1991-01-01T23:59:59.000Z

478

Software and codes for analysis of concentrating solar power technologies.  

DOE Green Energy (OSTI)

This report presents a review and evaluation of software and codes that have been used to support Sandia National Laboratories concentrating solar power (CSP) program. Additional software packages developed by other institutions and companies that can potentially improve Sandia's analysis capabilities in the CSP program are also evaluated. The software and codes are grouped according to specific CSP technologies: power tower systems, linear concentrator systems, and dish/engine systems. A description of each code is presented with regard to each specific CSP technology, along with details regarding availability, maintenance, and references. A summary of all the codes is then presented with recommendations regarding the use and retention of the codes. A description of probabilistic methods for uncertainty and sensitivity analyses of concentrating solar power technologies is also provided.

Ho, Clifford Kuofei

2008-12-01T23:59:59.000Z

479

Experimental Measurements of Concentration Fluctuations and Scales in a Dispersing Plume in the Atmospheric Surface Layer Obtained Using a Very Fast Response Concentration Detector  

Science Conference Proceedings (OSTI)

High-frequency fluctuations of concentration in a plume dispersing in the atmospheric surface layer have been measured with high-resolution concentration detectors (approximately 270 Hz at the ?6-dB point) to extract various concentration ...

Eugene Yee; R. Chan; P. R. Kosteniuk; G. M. Chandler; C. A. Biltoft; J. F. Bowers

1994-08-01T23:59:59.000Z

480

Thermal test procedure for a paraboloid concentrator solar cooker  

SciTech Connect

Suitable thermal tests have been identified for performance evaluation of a concentrating solar cooker. These tests provide parameters that characterize the performance of the solar cooker, and are more or less independent of the climatic variables. The overall heat loss factor is obtained from the cooling curve and the optical efficiency factor is determined from the heating curve - both under full load conditions. The performance characteristic curve for the solar cooker is obtained and discussed. The study indicates that the no load test, which is useful in the case of a box type solar cooker, is not appropriate in the case of concentrator type cookers.

Mullick, S.C.; Kandpal, T.C.; Kumar, S. (Indian Institute of Technology, New Delhi (India))

1991-01-01T23:59:59.000Z

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


481

Indoor radon and decay products: Concentrations, causes, and control strategies  

SciTech Connect

This report is another in the on going technical report series that addresses various aspects of the DOE Radon Research Program. It provides an overview of what is known about the behavior of radon and its decay products in the indoor environment and examines the manner in which several important classes of factors -- structural, geological, and meteorological -- affect indoor radon concentrations. Information on US indoor radon concentrations, currently available monitoring methods and novel radon control strategies are also explored. 238 refs., 22 figs., 9 tabs.

Nero, A.V.; Gadgil, A.J.; Nazaroff, W.W.; Revzan, K.L.

1990-11-01T23:59:59.000Z

482

Advanced solar concentrator development in the United States  

DOE Green Energy (OSTI)

Sandia National Laboratories is the lead laboratory for the United States Department of Energy's program to develop, build, and test advanced solar concentrators that are low in cost, have high performance, and demonstrate a long lifetime. The principal focus of DOE's concentrator program is on the development of heliostats for central receiver power plants and point focus parabolic dishes for use with a 25-kWe Stirling engine. The status and future plans of DOE's program in each area are reviewed. 29 refs., 7 figs.

Alpert, D.J.

1990-01-01T23:59:59.000Z

483

Method and Apparatus for Concentrating Vapors for Analysis  

DOE Patents (OSTI)

An apparatus and method are disclosed for pre-concentrating gaseous vapors for analysis. The invention finds application in conjunction with, e.g., analytical instruments where low detection limits for gaseous vapors are desirable. Vapors sorbed and concentrated within the bed of the apparatus can be thermally desorbed achieving at least partial separation of vapor mixtures. The apparatus is suitable, e.g., for preconcentration and sample injection, and provides greater resolution of peaks for vapors within vapor mixtures, yielding detection levels that are 10-10,000 times better than for direct sampling and analysis systems. Features are particularly useful for continuous unattended monitoring applications.

Grate, Jay W. (West Richland, WA); Baldwin, David L. (Kennewick, WA); Anheier, Jr., Norman C. (Richland, WA)

2008-10-07T23:59:59.000Z

484

Generating Hydrogen through Water Electrolysis using Concentrator Photovoltaics  

Science Conference Proceedings (OSTI)

Hydrogen can be an important element in reducing global climate change if the feedstock and process to produce the hydrogen are carbon free. Using nuclear energy to power a high temperature water electrolysis process meets these constraints while another uses heat and electricity from solar electric concentrators. Nuclear researchers have estimated the cost of hydrogen generated in this fashion and we will compare their estimates with those we have made for generating hydrogen using electricity and waste heat from a dish concentrator photovoltaic system. The conclusion is that the costs are comparable and low enough to compete with gasoline costs in the not too distant future.

McConnell, R.; Thompson, J.

2005-01-01T23:59:59.000Z

485

Generator configuration for solid oxide fuel cells  

DOE Patents (OSTI)

Disclosed are improvements in a solid oxide fuel cell generator 1 having a multiplicity of electrically connected solid oxide fuel cells 2, where a fuel gas is passed over one side of said cells and an oxygen-containing gas is passed over the other side of said cells resulting in the generation of heat and electricity. The improvements comprise arranging the cells in the configuration of a circle, a spiral, or folded rows within a cylindrical generator, and modifying the flow rate, oxygen concentration, and/or temperature of the oxygen-containing gases that flow to those cells that are at the periphery of the generator relative to those cells that are at the center of the gener