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A comparison of spanwise aerodynamic loads estimated from measured bending moments versus direct pressure measurements on horizontal axis wind turbine blades

Description: Two methods can be used to determine aerodynamic loads on a rotating wind turbine blade. The first is to make direct pressure measurements on the blade surface. This is a difficult process requiring costly pressure instrumentation. The second method uses measured flap bending moments in conjunction with analytical techniques to estimate airloads. This method, called ALEST, was originally developed for use on helicopter rotors and was modified for use on horizontal axis wind turbine blades. Esti… more
Date: October 1, 1991
Creator: Simms, D A & Butterfield, C P
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigations of CuInSe sub 2 Thin Films and Contacts

Description: This report describes research into electrical contacts for copper indium diselenide (CuInSe{sub 2}) polycrystalline thin films used for solar cell applications. Molybdenum contacts have historically been the most promising for heterojunction solar cells. This program studied contact stability by investigating thermally induced bilayer reactions between molybdenum and copper, indium, and selenium. Because selenization is widely used to fabricate CuInSe{sub 2} thin films for photovoltaic cells, … more
Date: October 1, 1991
Creator: Nicolet, M. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Improved tunnel resistance of silvered-polymer mirrors

Description: This report documents the research performed at the Solar Energy Research Institute during fiscal year (FY) 1991 to develop ways to prevent delamination failure (known as tunneling) of silvered-polymer reflector materials. Several promising approaches have been identified and demonstrated that substantially reduce such failures. These approaches include (1) use of Tedlar edge tape rather than the manufacturer-recommended ECP-244 tape, (2) thermal treatment of laminated reflector/substrate const… more
Date: October 1, 1991
Creator: Jorgensen, G.; Schissel, P.; Kennedy, C.; Shinton, Y.; Powell, D. & Siebarth, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thermal testing of the proposed HUD energy efficiency standard for new manufactured homes

Description: Thermal testing of two manufactured homes was performed at the National Renewable Energy Laboratory's (NREL's) Collaborative Manufactured Buildings Facility for Energy Research and Testing (CMFERT) environmental enclosure in the winter and spring of 1991. The primary objective of the study was to directly measure the thermal performance of the two homes, each built according to a proposed new US Department of Housing and Urban Development (HUD) standard. Secondary objectives were to test the ac… more
Date: June 1, 1992
Creator: Judkoff, R.D. & Barker, G.M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Aquatic species project report: FY 1991

Description: This report summarizes the progress and research accomplishments of the Aquatic Species Project, which is managed by the National Renewable Energy Laboratory for the US Department of Energy. The project is focused on applying genetic engineering techniques to enhance the lipid, or oil, production of microalgae. Those lipids can be extracted and processed into high-energy liquid fuels such as diesel. Because microalgae require carbon dioxide, a major greenhouse'' gas, as a nutrient, project rese… more
Date: April 1, 1992
Creator: Brown, L.M. (National Renewable Energy Lab., Golden, CO (United States)) & Sprague, S. (USDOE, Washington, DC (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Advanced high efficiency concentrator cells

Description: 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… more
Date: June 1, 1992
Creator: Gale, R. (Varian Associates, Inc., Palo Alto, CA (United States). Varian Research Center)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Evaluation of Wastewater Treatment Requirements for Thermochemical Biomass Liquefaction

Description: Biomass can provide a substantial energy source. Liquids are preferred for use as transportation fuels because of their high energy density and handling ease and safety. Liquid fuel production from biomass can be accomplished by any of several different processes including hydrolysis and fermentation of the carbohydrates to alcohol fuels, thermal gasification and synthesis of alcohol or hydrocarbon fuels, direct extraction of biologically produced hydrocarbons such as seed oils or algae lipids,… more
Date: April 1, 1992
Creator: Elliott, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparison of Predicted Optical Performance With Measured Results for Dish Concentrators

Description: Several optical design tools have been developed at the National Renewable Energy Laboratory (NREL) during the past two years. These have been used extensively both in-house and by industry to analyze dish concentrator systems and to optimize performance of such designs. The first program, OPTDSH, models single-element dish concentrators. The second code, ODMF, allows multifacet dish arrays to be modeled. The accuracy of performance simulations by these programs has been established by comparin… more
Date: April 1, 1991
Creator: Jorgensen, G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Shining On: A primer on solar radiation data

Description: This document is a primer on solar radiation data. General uses of solar energy are presented. The manner in which solar radiation data is used to aid engineers in optimizing the use of solar thermal conversion and photovoltaic conversion is discussed. Methods for acquiring and assimilating the solar radiation data are illustrated. This would include the design and use of pyranometers and pyrheliometers. Seasonal and geographical variations in solar flux reaching the earth are evaluated. Other … more
Date: May 1, 1992
Creator: Dunlap, M.A.; Cook, G. (eds.); Marion, B.; Riordan, C. & Renne, D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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NREL PV AR D 11th review meeting, May 13--15, 1992, Denver Marriott City Center, Denver, Colorado

Description: This is a collection of abstracts from papers presented at the National Renewable Energy Laboratory (NREL) Photovoltaic (PV) research and development review meeting held May 1992. Subject areas covered include solar cell and solar module manufacturing and development, materials, polycrystalline thin films, applications, amorphous silicon, solar cell performance and testing, crystalline silicon and other photovoltaic and safety perspectives. (GHH)
Date: January 1, 1992
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Catalyst and Feedstock Effects in the Thermochemical Conversion of Biomass to Liquid Transportation Fuels

Description: The thermochemical conversion of biomass feedstocks to liquid transportation fuels can be accomplished by three processes, namely gasification, high-pressure liquefaction, and pyrolysis. In this study, the pyrolysis option is selected which is followed by the catalytic upgrading of pyrolysis vapors to aromatic and olefinic hydrocarbons (PYROCAT process). The aromatics constitute a high-octane gasoline blend, while the olefins can be utilized as feedstocks for various chemicals. The PYROCAT proc… more
Date: May 1992
Creator: Rejai, B.; Agblevor, F. A.; Evans, R. J. & Wang, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photodegradation effects in materials exposed to high flux solar and solar simulated radiation

Description: This report contains study results about photodegradation effects in materials exposed to high flux solar and solar simulated radiation. The studies show that high flux photoirradiation of materials can result in significant changes in the stability of materials. Photodesorption and photo-enhanced oxidation were determined to be the major mechanisms. These mechanisms were shown to affect, in extremely adverse ways, the expected thermal stability of solar relevant materials, especially stainless… more
Date: April 1, 1992
Creator: Ignatiev, A
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Research on polycrystalline thin film submodules based on CuInSe sub 2 materials

Description: This report describes progress during the first year of a three-year research program to develop 12%-efficient CuInSe{sub 2} (CIS) submodules with area greater than 900 cm{sup 2}. To meet this objective, the program was divided into five tasks: (1) windows, contacts, substrates; (2) absorber material; (3) device structure; (4) submodule design and encapsulation; and (5) process optimization. In the first year of the program, work was concentrated on the first three tasks with an objective to de… more
Date: May 1, 1992
Creator: Catalano, A.; Arya, R.; Carr, L.; Fieselmann, B.; Lommasson, T.; Podlesny, R. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Perspective on photovoltaic amorphous silicon

Description: Amorphous silicon is a thin film option that has the potential for a cost-effective product for large-scale utility photovoltaics application. The initial efficiencies for single-junction and multijunction amorphous silicon cells and modules have increased significantly over the past 10 years. The emphasis of research and development has changed to stabilized efficiency, especially that of multijunction modules. NREL has measured 6.3%--7.2% stabilized amorphous silicon module efficiencies for U… more
Date: May 1, 1992
Creator: Luft, W.; Stafford, B. & von Roedern, B.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A surface definition code for turbine blade surfaces

Description: A numerical interpolation scheme has been developed for generating the three-dimensional geometry of wind turbine blades. The numerical scheme consists of (1) creating the frame of the blade through the input of two or more airfoils at some specific spanwise stations and then scaling and twisting them according to the prescribed distributions of chord, thickness, and twist along the span of the blade; (2) transforming the physical coordinates of the blade frame into a computational domain that … more
Date: May 1, 1992
Creator: Yang, S.L. (Michigan Technological Univ., Houghton, MI (United States)); Oryang, D. & Ho, M.J. (Tuskegee Univ., AL (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Yaw dynamics of horizontal axis wind turbines

Description: Designers of a horizontal axis wind turbine yaw mechanism are faced with a difficult decision. They know that if they elect to use a yaw- controlled rotor then the system will suffer increased initial cost and increased inherent maintenance and reliability problems. On the other hand, if they elect to allow the rotor to freely yaw they known they will have to account for unknown and random, though bounded, yaw rates. They will have a higher-risk design to trade-off against the potential for cos… more
Date: May 1, 1992
Creator: Hansen, A.C. (Utah Univ., Salt Lake City, UT (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High-flux solar photon processes

Description: This study was commissioned by the National Renewable Energy Laboratory (NREL) for the purpose of identifying high-flux photoprocesses that would lead to beneficial national and commercial applications. The specific focus on high-flux photoprocesses is based on the recent development by NREL of solar concentrator technology capable of delivering record flux levels. We examined photolytic and photocatalytic chemical processes as well as photothermal processes in the search for processes where co… more
Date: June 1, 1992
Creator: Lorents, D C; Narang, S; Huestis, D C; Mooney, J L; Mill, T; Song, H K et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Module process optimization and device efficiency improvement for stable, low-cost, large-area, cadmium telluride-based photovoltaic module production

Description: This report describes work under a three-year phased subcontract to develop CdS/CdTe devices and modules and to further improve the technology base at Photon Energy, Inc. (PEI) to better address the commercialization issues and objectives of the PEI and the US Department of Energy. During this reporting period we (1) achieved efficiencies of 12.7% on small area devices, (2) achieved 1-ft{sup 2} modules with over 8% aperture-area efficiency (and active area efficiencies up to {approximately}10%)… more
Date: April 1, 1992
Creator: Albright, S. P.; Ackerman, B.; Chamberlin, R. R. & Jordan, J. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application Experience and Field Performance of Silvered Polymer Reflectors

Description: The solar-weighted hemispheric reflectance of unweathered silvered acrylic mirrors exceeds 92%, and specular reflectance into a 4- milliradian, full-cone acceptance angle is greater than 90%. Comparison of outdoor and accelerated tests suggests that the protected silver can resist corrosion for the five-year life that is the current goal. An installation of parabolic troughs has been cleaned monthly for two years, and reflectance is regularly returned to within a few percent of the initial refl… more
Date: April 1, 1991
Creator: Schissel, P.; Jorgensen, G. & Pitts, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Desiccant cooling using unglazed transpired solar collectors

Description: The use of unglazed solar collectors for desiccant regeneration in a solid desiccant cooling cycle was investigated because these collectors are lower in cost than conventional glazed flat-plate collectors. Using computer models, the performance of a desiccant cooling ventilation cycle integrated with either unglazed transpired collectors or conventional glazed flat-plate collectors was obtained. We found that the thermal performance of the unglazed system was lower than the thermal performance… more
Date: May 1, 1992
Creator: Pesaran, A. A. & Wipke, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Computer simulation of shading and blocking: Discussion of accuracy and recommendations

Description: A field of heliostats suffers losses caused by shading and blocking by neighboring heliostats. The complex geometry of multiple shading and blocking events suggests that a processing code is needed to update the boundary vector for each shading or blocking event. A new version, RSABS, (programmer's manual included) simulates the split-rectangular heliostat. Researchers concluded that the dominant error for the given heliostat geometry is caused by the departure from planarity of the neighboring… more
Date: April 1, 1992
Creator: Lipps, F.W. (Houston Univ., TX (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photovoltaic Subcontract Program, FY 1991

Description: This report summarizes the fiscal year (FY) 1991 (October 1, 1990, through September 30, 1991) progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL) -- formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the… more
Date: March 1, 1992
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Thin film cadmium telluride, zinc telluride, and mercury zinc telluride solar cells

Description: This report describes research to demonstrate (1) thin film cadmium telluride solar cells with a quantum efficiency of 75% or higher at 0. 44 {mu}m and a photovoltaic efficiency of 11.5% or greater, and (2) thin film zinc telluride and mercury zinc telluride solar cells with a transparency to sub-band-gap radiation of 65% and a photovoltaic conversion efficiency of 5% and 8%, respectively. Work was directed at (1) depositing transparent conducting semiconductor films by solution growth and meta… more
Date: April 1, 1992
Creator: Chu, T.L. (University of South Florida, Tampa, FL (United States))
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Photoelastic stress analysis on a Phoenix 7. 9-meter blade

Description: Photoelastic tests were conducted on the Phoenix 7.9-meter blade to develop the basic methodology for locating critical strain areas on full-scale composite structures. Under relatively low elastic loading the strain fields over various regions on the blade planform were documented with 35mm photographs under different loading conditions at the Solar Energy Research Institute (SERI) Structural Test Facility (STF). Strain concentrations were easily located and quantified. Principal strain magnit… more
Date: October 1, 1991
Creator: Musial, W. D.; Jenks, M. D.; Osgood, R. M. & Johnson, J. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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