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Extra focal convective suppressing solar collector. Final technical progress report

Description: This progress report describes work done on the Extra Focal Convective Suppressing Solar Collector. The topics of the report include sensor refinement for the tracking electronics, tracking controller refinement, system optics evaluation, absorber system material evaluation and performance, tracking hardware evaluation and refinement, and full scale prototype construction and testing.
Date: May 1, 1996
Partner: UNT Libraries Government Documents Department

Solar kinetics` photovoltaic concentrator module and tracker development

Description: 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.
Date: November 1, 1995
Creator: White, D.L. & Howell, B.
Partner: UNT Libraries Government Documents Department

[Energy education exhibits for Insights El Paso Science Museum]

Description: The grant in question, DE-FG03-94ER75954, was awarded to Insights El Paso Science Museum to build key exhibits. These exhibits helped the Museum fulfill its mission to ``promote curiosity and stimulate interest by exploratory, entertaining, exciting, and participatory learning in a broad range of scientific disciplines to persons of all ages regionally and internationally.`` There are several current Board of Directors members who also were Board members during the grant period and who helped construct some of the exhibits. Through speaking with them and reviewing minutes of Board meetings during 1994, it has been determined that seven of the ten proposed exhibits were constructed, with an eighth exhibit constructed as an alternative. Photos of seven of the exhibits and preliminary sketches of some are attached. Following is a list of the constructed exhibits: Hot or Cold, Give and Take, Conduction, Convection, Sources of Energy, Wind Generator, Solar Tracker, and Perpetual Motion.
Date: May 27, 1998
Creator: Shubinski, R.
Partner: UNT Libraries Government Documents Department

Development of a low-cost integrated 20-kW-AC solar tracking subarray for grid-connected PV power system applications. Final technical report

Description: This report chronicles Utility Power Group's (UPG) successful two-year Photovoltaic Manufacturing Technology (PVMaT) Phase 4A1 work effort which began in July, 1995. During this period, UPG completed design, fabrication, testing and demonstration of a modular and fully integrated 15-kW-ac, solar tracking PV power system sub-array. The two key and innovative components which were developed are a Modular Panel which optimizes factory assembly of PV modules into a large area, field-deployable, structurally-integrated PV panel, and an Integrated Power Processing Unit which combines all dc and ac power collection, conversion and control functions within a single, field-deployable structurally-integrated electrical enclosure. These two key sub-array elements, when combined with a number of other electrical, mechanical, and structural components, create a low-cost and high-performance PV power system. This system, or sub-array, can be deployed in individual units, or paralleled with any number of other sub-arrays, to construct multi-megawatt P fields. 21 figs.
Date: June 1, 1998
Creator: Stern, M.; Duran, G.; Fourer, G.; Mackamul, K.; Whalen, W.; Loo, M. van et al.
Partner: UNT Libraries Government Documents Department

Feasibility Study of Economics and Performance of Solar Photovoltaics in Nitro, West Virginia

Description: The study described in this report assessed brownfield sites designated by the City of Nitro, West Virginia for solar photovoltaic (PV) installations. The study analyzed three different types of PV systems for eight sites. The report estimates the cost, performance, and site impacts of thin film technology and crystalline silicon panels (both fixed-axis tracking and single-axis tracking systems). Potential job creation and electrical rate increases were also considered, and the report recommends financing options that could assist in the implementation of a system.
Date: August 1, 2010
Creator: Lisell, L. & Mosey, G.
Partner: UNT Libraries Government Documents Department

Wind energy/geothermic/solar heating system. Final report

Description: I've observed three distinct ''camps'' of renewable energy resources; WIND, Geothermic, and Solar. None of the three are completely adequate for the NE by themselves. I observe little effort to combine them to date. My objective has been to demonstrate that the three can be combined in a practical system. To mitagate the high cost and poor payback for individual residences, I believe neighborhoods of 4 to 5 homes, apartment complexes or condominiums could form an Energy Association alloting a piece of ground (could be a greenbelt) which would contain the well or wells, solar boosted underground water storage and the Solar banks. These are the high cost items which could be prorated and ammortized by the Association. Easements would permit each residence underground insulated water lines for individual heat pump conversions to existing forced air furnaces. Where regulations permit, an individual home could erect his own windmill to belt drive his freon compressor. With or without the optional windmill the water to freon heat pump with its solar boosts on the well water, will enjoy COP's (coefficient of Performances or times better than electric resistance heat) beyond anything on the market today. In a neighborhood energy association, all trenching could be done together all plumbing could be one contract and they could qualify for quantity discounts on heat pump units, chillers and components and installation.
Date: January 1, 1981
Partner: UNT Libraries Government Documents Department

Design of the support structure, drive pedestal, and controls for a solar concentrator

Description: The glass/metal McDonnell-Douglas dish is the state-of-the-art of parabolic dish concentrators. Because of the perceived high production cost of this concentrator, the Department of Energy's Solar Thermal Program is developing stretch-membrane technology for large (75 kWt) solar concentrators for integration with receivers and engines in 25 kWe dish-Stirling systems. The objective of this development effort is to reduce the cost of the concentrator while maintaining the high levels of performance characteristic of glass-metal dishes. Under contract to Sandia National Laboratories, Science Applications International Corporation, Solar Kinetics Inc. and WG Associates are developing a faceted stretched-membrane heliostat technology. This design will result in a low-risk, near-term concentrator for dish-Stirling systems. WG Associates has designed the support structure, drives and tracking controls for this dish. The structure is configured to support 12 stretched-membrane, 3.5-meter diameter facets in a shaped dish configuration. The dish design is sized to power a dish-Stirling system capable of producing 25 kW (electric). In the design of the structure, trade-off studies were conducted to determine the best'' facet arrangement, dish contour, dish focal length, tracking control and walk-off protection. As part of the design, in-depth analyses were performed to evaluate pointing accuracy, compliance with AISC steel design codes, and the economics of fabrication and installation. Detailed fabrication and installation drawings were produced, and initial production cost estimates for the dish were developed. These issues, and the final dish design, are presented in this report. 7 refs., 33 figs., 18 tabs.
Date: August 1, 1991
Creator: Goldberg, V.R.; Ford, J.L. & Anderson, A.E. (WG Associates, Dallas, TX (United States))
Partner: UNT Libraries Government Documents Department

Heat pipe dynamics. Final report, April 30, 1981. [Uses of heat pipe, especially in solar collector]

Description: A heat-pipe flat plate solar collector is constructed like a typical flat plate collector with the exception that individual heat pipes are attached to the collector surface to transfer collected heat via a phase change from collector surface into an attached jacket containing a phase change material. The efficiency of such a collector was measured roughly. Also briefly described are: a heat-pipe heat exchanger, heat-pipe heat exchanger freeze proofing, heat-pipe attic ventilation, transfer of light bulb heat via a heat pipe to heat water, heat recovery via heat pipe, cooling of oil in engines and transmissions via heat pipe, a tracking reflector, automatic sun tracker, single-stroke vacuum pump for heat-pipe manufacture, and heat pipe heat transfer from rock bed. (LEW)
Date: January 1, 1981
Creator: Norman, R.M. Sr.
Partner: UNT Libraries Government Documents Department

Solar tracking system

Description: This report describes an automated solar tracking system which is adaptable to most solar collectors which require alignment with the sun's radiation. The system uses partially shaded photovoltaic solar cells to produce error signals for both elevation and azimuth tracking with a high degree of accuracy. An electrical circuit processes the error signals and controls gearmotors to direct the solar collector toward the sun.
Date: June 1, 1977
Creator: Hammons, B.E.
Partner: UNT Libraries Government Documents Department

Photovoltaic concentrator initiative: Concentrator cell development

Description: 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.
Date: May 1, 1993
Creator: Wohlgemuth, J. H. & Narayanan, S.
Partner: UNT Libraries Government Documents Department

Recent advances in outdoor performance evaluation of PV systems

Description: Sandia`s Photovoltaic Technology Laboratory (PTEL) routinely performs outdoor tests of a variety of one-sun and concentrator PV modules. The authors experience is that while outdoor testing has its own set of problems, it can produce results that are more directly applicable to ``field`` conditions than testing in solar simulators. They have recently improved both the hardware and software at the PTEL to improve their accuracy and to deal with the special set of problems encountered in outdoor testing. Improvements in hardware include a computer-controlled solar tracker that allows us to test arrays up to 21 m{sup 2} in size; infrared imaging of modules; and electronic loads that allow us to test components with outputs up to 1,800 watts. Improvements in software include real-time monitoring of data collection; a relational data base that has improved the reliability of test setups, operations and analyses; and a standardized reporting process that relates module performance to a number of environmental parameters.
Date: December 31, 1992
Creator: Quintana, M. A.; King, D. L.; Cannon, J. E.; Woodworth, J. R.; Boyson, W. E.; Adams, N. P. et al.
Partner: UNT Libraries Government Documents Department