Search Results

Advanced search parameters have been applied.
open access

Potential of Photovoltaics

Description: Presented at the Association of Industrial Metallizers, Coaters and Laminators (AIMCAL) Fall Technical Conference 2008 and 22nd International Vacuum Web Coating Conference held October 19-22, 2008 in Myrtle Beach, South Carolina. This presentation discusses PV in the world energy portfolio, PV basics, PV technologies, and vacuum web-coating applications in PV.
Date: October 22, 2008
Creator: Nelson, B. P.
Partner: UNT Libraries Government Documents Department

National Fuel Cell Vehicle Learning Demonstration: Status and Results

Description: The objectives of this paper are: (1) validate H{sub 2} FC vehicles and infrastructure in parallel; (2) identify current status and evolution of the technology; (3) objectively assess progress toward technology readiness; and (4) provide feedback to H{sub 2} research and development.
Date: April 22, 2009
Creator: Wipke, K.; Sprik, S.; Kurtz, J.; Ramsden, T. & Garbak, J.
Partner: UNT Libraries Government Documents Department
open access

New Microscopic Model of the Staebler-Wronski Effect in Hydrogenated Amorphous Silicon

Description: A new microscopic and kinetic model of light-induced metastability in hydrogenated amorphous silicon (a-Si:H) was recently proposed. Carrier recombination excites H from deep Si-H bonds into a mobile configuration, leaving a threefold-coordinated Si dangling bond (DB) defect at the site of excitation - a process long suspected to be an element of metastable DB production. Normally, mobile H are recaptured at DB defects and neither metastability nor net DB production results. However, when two m… more
Date: October 22, 1998
Creator: Branz, H. M.
Partner: UNT Libraries Government Documents Department
open access

Methane Recovery from Animal Manures The Current Opportunities Casebook

Description: Growth and concentration of the livestock industry create opportunities for the proper disposal of the large quantities of manures generated at dairy, swine, and poultry farms. Pollutants from unmanaged livestock wastes can degrade the environment, and methane emitted from decomposing manure may contribute to global climate change. One management system not only helps prevent pollution but can also convert a manure problem into a new profit center. Economic evaluations and case studies of opera… more
Date: September 22, 1998
Creator: Lusk, P.
Partner: UNT Libraries Government Documents Department
open access

A Silicon Ingot Lifetime Tester for Industrial Use

Description: A specially designed lifetime measurement instrument has been developed to characterize silicon ingots before they are subjected to expensive slicing and solar-cell processing, thereby saving needless processing costs of inferior materials in a solar-cell production line. The instrument uses the direct-current photoconductance decay (DC-PCD) method for linear detection of the transient photoconductance signal and localized probing / illumination for necessary sensitivity on low resistivity and … more
Date: October 22, 1998
Creator: Wang, T. H.; Ciszek, T. F.; Landry, M.; Matthaus, A. & Mihalik, G.
Partner: UNT Libraries Government Documents Department
open access

Direct measurement of density-of-states effective mass and scattering parameter in transparent conducting oxides using second-order transport phenomena

Description: The Boltzmann transport equation can be solved to give analytical solutions to the resistivity, Hall, Seebeck, and Nernst coefficients. These solutions may be solved simultaneously to give the density-of-states (DOS) effective mass, the Fermi energy relative to either the conduction or valence band, and a scattering parameter that is related to a relaxation time and the Fermi energy. The Nernst coefficient is essential for determining the scattering parameter and, thereby, the effective scatter… more
Date: March 22, 2000
Creator: Young, D. L.; Coutts, T. J. (NREL); Kaydanov, V. I. (Colorado School of Mines) & Mulligan, W. P. (Sunpower, Inc.)
Partner: UNT Libraries Government Documents Department
open access

Technologies for the new millennium: Photovoltaics as a distributed resource

Description: Photovoltaics (PV) is emerging as an important distributed resource. PV gives both the benefits of a distributed resource and a clean power source. Because PV can be installed at both residential and commercial locations, it can be used to reduce peak demand when its output is properly matched with power demand. It can also improve asset utilization by requiring less large capital generation spending and delaying some equipment replacement. With the price of some grid-connected PV systems expec… more
Date: March 22, 2000
Creator: Kroposki, B. & DeBlasio, R.
Partner: UNT Libraries Government Documents Department
open access

Thin film CuIn{sub 1{minus}x}Ga{sub x}Se-based solar cells prepared from solution-based precursors

Description: The authors have fabricated high-efficiency thin-film CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} (CIGS)-based photovoltaic devices from solution-based electroplated (EP) and auto-plated (AP) precursors. As-deposited precursors are Cu-rich CIGS. Compositions were adjusted to CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} with additional In and Ga by physical vapor deposition (PVD) to the EP and AP precursor films. Auger analysis and grazing incident X-ray diffraction (GIXRD) were performed on devices prepared… more
Date: May 22, 2000
Creator: Bhattacharya, R. N.; Balcioglu, A.; Ramanathan, K. & Batchelor, W. K., Ahrenkiel, R. K.
Partner: UNT Libraries Government Documents Department
open access

Buildings for the 21st Century Newsletter: Fall 1999, Vol. 2, No. 1

Description: This edition contains more information about new efforts and programs in DOE's Office of Building Technology, State and Community Programs (BTS), and highlights the evolution of a new approach to making buildings more energy-efficient, comfortable, and affordable.
Date: November 22, 1999
Creator: National Renewable Energy Laboratory (U.S.)
Partner: UNT Libraries Government Documents Department
open access

Electrical Characterization of Etched Grain-Boundary Properties from As-Processed px-CdTe Based Solar Cells

Description: An ability to lift off or separate the thin-film polycrystalline CdTe from the CdS, without the use of chemical etches, has enabled direct electrical characterization of the as-processed CdTe near the CdTe/CdS heterointerface. We use this ability to understand how a back-contact, nitric-phosphoric (NP) etch affects the grain boundaries throughout the film. Quantitative determination of the grain-boundary barrier potentials and estimates of doping density near the grain perimeter are determined … more
Date: October 22, 1998
Creator: Woods, L. M.; Robinson, G. Y. (Colorado State University, Ft. Collins, CO) & Levi, D. H. (National Renewable Energy Laboratory) Kaydanov, V. (Colorado School of Mines, Golden, CO)
Partner: UNT Libraries Government Documents Department
open access

NREL Unsteady Aerodynamics Experiment in the NASA-Ames Wind Tunnel: A Comparison of Predictions to Measurements

Description: Currently, wind turbine designers rely on safety factors to compensate for the effects of unknown loads acting on the turbine structure. This results in components that are overdesigned because precise load levels and load paths are unknown. To advance wind turbine technology, the forces acting on the turbine structure must be accurately characterized because these forces translate directly into loads imparted to the wind turbine structure and resulting power production. Once these forces are m… more
Date: June 22, 2001
Creator: Simms, D.; Schreck, S.; Hand, M. & Fingersh, L. J.
Partner: UNT Libraries Government Documents Department
open access

Transpired Air Collectors - Ventilation Preheating

Description: Many commercial and industrial buildings have high ventilation rates. Although all that fresh air is great for indoor air quality, heating it can be very expensive. This short (2-page) fact sheet describes a technology available to use solar energy to preheat ventilation air and dramatically reduce utility bills.
Date: June 22, 2006
Creator: Christensen, C.
Partner: UNT Libraries Government Documents Department
open access

Guide to alternative fuel vehicle incentives and laws: September 1998

Description: This guide provides information in support of the National Clean Cities Program, which will assist one in becoming better informed about the choices and options surrounding the use of alternative fuels and the purchase of alternative fuel vehicles. The information printed in this guide is current as of September 15, 1998. For recent additions or more up-to-date information, check the Alternative Fuels Data Center Web site at http://www.afdc.doe.gov
Date: December 22, 1998
Creator: Riley, C. & O'Connor, K.
Partner: UNT Libraries Government Documents Department
open access

Recent developments in high-efficiency PV cells

Description: Enormous progress has been made in recent years on a number of photovoltaic (PV) materials and devices in terms of conversion efficiencies. Ultrahigh-efficiency (>30{percent}) PV cells have been fabricated from gallium arsenide (GaAs) and its ternary alloys such as gallium indium phosphide (GaInP{sub 2}). The high-efficiency GaAs-based solar cells are being produced on a commercial scale, particularly for space applications. Efficiencies in the range of 18{percent} to 24{percent} have been a… more
Date: May 22, 2000
Creator: Deb, S.
Partner: UNT Libraries Government Documents Department
open access

Particulate Contacts to Si and CdTe: Al, Ag, Hg-Cu-Te, and Sb-Te

Description: Our team has been investigating the use of particle-based contacts in both Si and CdTe solar cell technologies. First, in the area of contacts to Si, powders of Al and Ag prepared by an electroexplosion process have been characterized by transmission electron microscopy (TEM), TEM elemental determination X-ray spectroscopy (TEM-EDS), and TEM electron diffraction (TEM-ED). These Al and Ag particles were slurried and tested as contacts to p- and n-type silicon wafers, respectively. Linear current… more
Date: October 22, 1998
Creator: Schulz, D. L.; Ribelin, D.; Curtis, C. J. & Ginley, D. S.
Partner: UNT Libraries Government Documents Department
open access

Effects of Substrate and Na Concentration on Device Properties, Junction Formation, and Film Microstructure in CuInSe2PV Devices

Description: Different concentrations of Na were systematically introduced into CuInSe2 (CIS) photovoltaic solar cell absorber material on different substrates (SLG, Si02/SLG, 7059, alumina) to: (1) determine the resultant effects on device properties, junction formation, and material microstructure; and (2) determine the optimal range of Na concentrations in the CIS films per specific substrate. In general, finished devices show improved Voc, Jsc, and device efficiency, improved charge-collection efficienc… more
Date: October 22, 1998
Creator: Matson, R. J.; Granata, J. E.; Asher, S. E. & Young, M. R.
Partner: UNT Libraries Government Documents Department
open access

The technology roadmap for plant/crop-based renewable resources 2020

Description: The long-term well-being of the nation and maintenance of a sustainable leadership position in agriculture, forestry, and manufacturing, clearly depend on current and near-term support of multidisciplinary research for the development of a reliable renewable resource base. This document sets a roadmap and priorities for that research. America needs leadership that will continue to recognize, support, and move rapidly to meet the need to expand the use of sustainable renewable resources. This ro… more
Date: February 22, 1999
Creator: McLaren, J.
Partner: UNT Libraries Government Documents Department
open access

FEMP: Showering with the sun at Chickasaw National Recreation Area case study

Description: This FEMP Technical Assistance Case Study describes the use of solar water heating at the Chickasaw National Recreation Area in Oklahoma. The solar systems are an environmentally sound and cost-effective way to heat water. By using renewable energy technologies to satisfy its mandate to provide services for visitors and protect the park system's natural resources, the National Park Service sets a good example for other Federal agencies and the general public.
Date: February 22, 1999
Creator: McIntyre, M.
Partner: UNT Libraries Government Documents Department
open access

Photoconductive properties of GaAs{sub 1{minus}x}N{sub x} double heterostructures as a function of excitation wavelength

Description: The ternary semiconductor GaAs{sub 1{minus}x}N{sub x} with 0 < x < 0.3 can be grown epitaxially on GaAs and has a very large bowing coefficient. The alloy bandgap can be reduced to about 1.0 eV with about a 3% nitrogen addition. In this work, the authors measured the internal spectral response and recombination lifetime of a number of alloys using the ultra-high frequency photoconductive decay (UHFPCD) method. The data shows that the photoconductive excitation spectra of the GaAs{sub 0.97… more
Date: May 22, 2000
Creator: Ahrenkiel, R. K.; Mascarenhas, A.; Johnston, S. W.; Zhang, Y.; Friedman, D. J. & Vernon, S. M.
Partner: UNT Libraries Government Documents Department
open access

Impact of Vehicle Air-Conditioning on Fuel Economy, Tailpipe Emissions, and Electric Vehicle Range: Preprint

Description: Vehicle air-conditioning can significantly impact fuel economy and tailpipe emissions of conventional and hybrid electric vehicles and reduce electric vehicle range. In addition, a new US emissions procedure, called the Supplemental Federal Test Procedure, has provided the motivation for reducing the size of vehicle air-conditioning systems in the US. The SFTP will measure tailpipe emissions with the air-conditioning system operating. Current air-conditioning systems can reduce the fuel economy… more
Date: September 22, 2000
Creator: Farrington, R. & Rugh, J.
Partner: UNT Libraries Government Documents Department
Back to Top of Screen