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Method for including operation and maintenance costs in the economic analysis of active solar energy systems

Description: For a developing technology such as solar energy, the costs for operation and maintenance (O and M) can be substantial. In the past, most economic analyses included these costs by simply assuming that an annual cost will be incurred that is proportional to the initial cost of the system. However, in assessing the economics of new systems proposed for further research and development, such a simplification can obscure the issues. For example, when the typical method for including O and M costs in an economic analysis is used, the O and M costs associated with a newly developed, more reliable, and slightly more expensive controller will be assumed to increase - an obvious inconsistency. The method presented in this report replaces this simplistic approach with a representation of the O and M costs that explicitly accounts for the uncertainties and risks inherent in the operation of any equipment. A detailed description of the data inputs required by the method is included as well as a summary of data sources and an example of the method as applied to an active solar heating system.
Date: August 1, 1986
Creator: Short, W.D.
Partner: UNT Libraries Government Documents Department

West Angeles Community Development Corporation final technical report on export market feasibility planning and research for the solar medical autoclave

Description: This report summarizes core findings from an investigation performed by the staff of West Angeles Community Development Corporation (CDC) regarding the feasibility of marketing the Solar Medical Autoclave (``autoclave``) in South Africa. The investigation was completed during 1997, the period prescribed by the Grant Award made by the U.S. Department of Energy on January 1, 1997, and was monitored by the National Renewable Energy Laboratory.
Date: April 20, 1998
Creator: Power, G.D.
Partner: UNT Libraries Government Documents Department

A comparison of on-axis and off-axis heliostat alignment strategies

Description: Heliostat installation and alignment costs will be an important element in future solar power tower projects. The predicted annual performances of on- and-off axis strategies are compared for 95 m{sup 2} flat-glass heliostats and an external, molten-salt receiver. Actual approaches to heliostat alignment that have been used in the past are briefly discussed, and relative strengths and limitations are noted. The optimal approach can vary with the application.
Date: March 1, 1996
Creator: Jones, S.A.
Partner: UNT Libraries Government Documents Department

Biomorphic robots as a persistent means for removing explosive mines

Description: The current variety and dispersion of explosive mines is a daunting technological problem for current sensory techniques. The bottom line is that the only way to insure a mine has been found and removed is to step on it. As this is an upsetting proposition for biological organisms like animals or children, this paper details a proposed non-biological method that may have validity following additional research into the new science of Biomorphic Machines. A Robobiologist at LANL has invented and developed a variety of {open_quotes}living{close_quotes} robots that are solar powered, legged, autonomous, adaptive to massive damage and terrain, and very inexpensive. This technology, called Nervous Net (Nv) design, allows for the creation of capable walking mechanisms (known as {open_quotes}Biomorphic Robots{close_quotes}) which rather than run on a {open_quotes}work{close_quotes} ethic, use {open_quotes}survivalist{close_quotes} design principles. These principles allow Nv based machines to continue doing work even after multiple limbs have been removed or damaged, and to dynamically negotiate complex terrains as an emergent property of their operation. They are not programmed, and indeed, the 12 transistor controller used keeps their electronic cost well below that of most pocket radios. It is suspected that in finding and removing randomly placed explosive mines, they may be an interesting, capable solution.
Date: April 1, 1995
Creator: Tilden, M.W.
Partner: UNT Libraries Government Documents Department

Exposure testing of solar absorber surfaces

Description: The Los Alamos National Laboratory has been involved in supporting, monitoring and conducting exposure testing of solar materials for approximately ten years. The Laboratory has provided technical monitoring of the IITRI, DSET, Lockheed, and Berry contracts and has operated the Los Alamos exposure Facility for over five years. This report will outline some of the past exposure testing, the testing still in progress, and describe some of the major findings. While this report will primarily emphasize solar absorber surfaces, some of the significant findings relative to advanced glazing will be discussed.
Date: January 1, 1986
Creator: Moore, S.W.
Partner: UNT Libraries Government Documents Department

Innovative point focus solar concentrator

Description: Acurex Corporation has a Cooperative Agreement with the United States Department of Energy (DOE) to design, build and test a 15-meter diameter Innovative Point Focus Solar Concentrator. This report presents the results of the Phase I prototype reflective panel optical test. The approach selected for this test was a quick, simple, and relatively inexpensive evaluation of the first outer reflective panel produced. This approach represented a tradeoff between extent of results and test costs. The test measured the focal quality of the panel, and this result was then related to the focal quality of the complete dish assembly.
Date: February 1, 1986
Partner: UNT Libraries Government Documents Department

Solar access of residential rooftops in four California cities

Description: Shadows cast by trees and buildings can limit the solar access of rooftop solar-energy systems, including photovoltaic panels and thermal collectors. This study characterizes residential rooftop shading in Sacramento, San Jose, Los Angeles and San Diego, CA. Our analysis can be used to better estimate power production and/or thermal collection by rooftop solar-energy equipment. It can also be considered when designing programs to plant shade trees. High-resolution orthophotos and LiDAR (Light Detection And Ranging) measurements of surface height were used to create a digital elevation model of all trees and buildings in a well-treed 2.5-4 km{sup 2} residential neighborhood. On-hour shading of roofing planes (the flat elements of roofs) was computed geometrically from the digital elevation model. Values in future years were determined by repeating these calculations after simulating tree growth. Parcel boundaries were used to determine the extent to which roofing planes were shaded by trees and buildings in neighboring parcels. For the subset of S+SW+W-facing planes on which solar equipment is commonly installed for maximum solar access, absolute light loss in spring, summer and fall peaked about two to four hours after sunrise and about two to four hours before sunset. The fraction of annual insolation lost to shading increased from 0.07-0.08 in the year of surface-height measurement to 0.11-0.14 after 30 years of tree growth. Only about 10% of this loss results from shading by trees and buildings in neighboring parcels.
Date: May 14, 2010
Creator: Levinson, Ronnen; Akbari, Hashem & Pomerantz, Melvin
Partner: UNT Libraries Government Documents Department

Solar lumber kiln. Final report

Description: The purpose of this project was to establish design parameters for the construction of small scale (1000 board foot capacity) lumber drying kiln which derives its thermal energy from the sun. Results of a six month monitoring period are presented, as well as second generation design considerations and simplified control logic. (LEW)
Date: January 1, 1977
Partner: UNT Libraries Government Documents Department

Low-cost solar collector test and evaluation. Final report

Description: Project was to test and evaluate a highly efficient low cost solar collector and to make this technology available to the average homeowner. The basic collector design was for use in mass production, so approximately forty collector panels were made for testing and to make it simple to be hand built. The collectors performed better than expected and written and visual material was prepared to make construction easier for a first time builder. Publicity was generated to make public aware of benefits with stories by Associated Press and in publications like Popular Science.
Date: unknown
Creator: Benjamin, C.M.
Partner: UNT Libraries Government Documents Department

Efficiency of a solar collector with internal boiling

Description: The behavior of a solar collector with a boiling fluid is analyzed to provide a simple algebraic model for future systems simulations, and to provide guidance for testing. The efficiency equation is developed in a form linear in the difference between inlet and saturation (boiling) temperatures, whereas the expression upon which ASHRAE Standard 109P is based utilizes the difference between inlet and ambient temperatures. The coefficient of the revised linear term is a weak function of collector parameters, weather, and subcooling of the working fluid. For a glazed flat-plate collector with metal absorber, the coefficient is effectively constant. Therefore, testing at multiple values of insolation and subcooling, as specified by ASHRAE 109P, should not be necessary for most collectors. The influences of collector properties and operating conditions on efficiency are examined.
Date: January 1, 1986
Creator: Neeper, D. A.
Partner: UNT Libraries Government Documents Department

Efficiency of a solar collector with internal boiling

Description: The behavior of a solar collector with a boiling fluid is analyzed to provide a simple algebraic model for future systems simulations, and to provide guidance for testing. The efficiency equation is developed in a form linear in the difference between inlet and saturation (boiling) temperatures, whereas the expression upon which ASHRAE Standard 109P is based utilizes the difference between inlet and ambient temperatures. The coefficient of the revised linear term is a week function of collector parameters, weather, and subcooling of the working fluid. For a glazed flat-plate collector with metal absorber, the coefficient is effectively constant. Therefore, testing at multiple values of insolation and subcooling, as specified by ASHRAE 109P, should not be necessary for most collectors. The influences of collector properties and operating conditions on efficiency are examined.
Date: June 1, 1986
Creator: Neeper, D.A.
Partner: UNT Libraries Government Documents Department

Solar Technology Acceleration Center (SolarTAC): Cooperative Research and Development Final Report, CRADA Number CRD-07-259

Description: This agreement allowed NREL to serve as an advisor on SolarTAC - a collaborative effort between Xcel Energy, NREL, and the University of Colorado at Boulder. The collaboration was formed to accelerate pre-commercial and early commercial solar energy technologies to the marketplace. Through this CRADA, NREL participated in the deployment of solar energy generation technologies and related solar equipment for research, testing, validation, and demonstration purposes.
Date: October 1, 2011
Creator: Kramer, W.
Partner: UNT Libraries Government Documents Department

Process development for automated solar cell and module production. Task 4: automated array assembly. Quarterly report No. 2

Description: Installation of the cell preparation station into its new enclosure is now complete and operation verification tests have been performed. The detailed layout drawings of the Automated Lamination Station have been produced and construction has begun. All major and most minor components have been delivered by vendors. The station framework has been built and assembly of components is underway. The final drawings for the Automated Vacuum Chamber are being completed and the first in-house components are being fabricated.
Date: January 15, 1981
Creator: Hagerty, J. J.
Partner: UNT Libraries Government Documents Department

US photovoltaic patents: 1991--1993

Description: This document contains US patents on terrestrial photovoltaic (PV) power applications, including systems, components, and materials as well as manufacturing and support functions. The patent entries in this document were issued from 1991 to 1993. The entries were located by searching USPA, the database of the US Patent Office. The final search retrieved all patents under the class ``Batteries, Thermoelectric and Photoelectric`` and the subclasses ``Photoelectric,`` ``Testing,`` and ``Applications.`` The search also located patents that contained the words ``photovoltaic(s)`` or ``solar cell(s)`` and their derivatives. After the initial list was compiled, most of the patents on the following subjects were excluded: space photovoltaic technology, use of the photovoltaic effect for detectors, and subjects only peripherally concerned with photovoltaic. Some patents on these three subjects were included when ft appeared that those inventions might be of use in terrestrial PV power technologies.
Date: March 1, 1995
Creator: Pohle, L
Partner: UNT Libraries Government Documents Department

Tracking instrument and control for solar concentrators. Final technical report, October 1979-January 1981

Description: The tracker uses a single photo sensor, and a rotating aperature to obtain tracking accuracies better than 1.5 mrads (0.1 degs). Peak signal detection is used to eliminate tracking of false sources, i.e., clouds, etc. A prism is employed to obtain an extended field of view (150 degs axially - 360 degs radially). The tracker digitally measures the Suns displacement angle relative to the concentrator axis, and repositions it incrementally. This arrangement permits the use of low cost non-servo motors. The local controller contains microprocessor based electronics, incorporating digital signal processing. A single controller may be time shared by a maximum of sixteen trackers, providing a high performance, cost effective solar tracking system, suitable for both line and point focus concentrators. An installation may have the local controller programmed as a standalone unit or slaved to a central controller. When used with a central controller, dynamic data monitoring and logging is available, together with the ability to change system modes and parameters, as desired.
Date: January 31, 1981
Creator: Gray, J & Kuhlman, J
Partner: UNT Libraries Government Documents Department

[News Clip: Meditation]

Description: Video footage from the KXAS-TV/NBC station in Fort Worth, Texas, to accompany a news story.
Date: May 5, 1980, 10:00 p.m.
Creator: KXAS-TV (Television station : Fort Worth, Tex.)
Partner: UNT Libraries Special Collections

Survey mirrors and lenses and their required surface accuracy. Semiannual technical progress report, September 15, 1978-April 15, 1979

Description: Since the beginning of widespread research and development for solar energy, a major concern has been the effect of optical and surface quality of collector materials on collector performance and the changes in these properties due to environmental conditions. In many instances, this type of data has not been compiled. When data is available on surface quality, mirror or lens optical characteristics, surface deformations due to stress and other errors, it is difficult to quantify the effect these have on a particular concentrator design performance. To further investigate these errors, Honeywell is performing a study of concentrator designs and mirror and lens surfaces. There are two taks within this program. The first task involves investigation and evaluation of concentrator performance. Within this task, Honeywell has conducted a survey of the literature, solar manufacturers and government information to obtain data on existing concentrator designs (i.e., V-troughs, parabolic mirror concentrators) and lens and mirror materials. Ten collector configurations have been selected to be mathematically modeled. These models will be incorporated into existing ray trace software and will be used to evaluate concentrator performance. Optical quality properties, structural deformations due to loading and stress, tracking errors and material property changes due to the environment will be included in this assessment of performance. The second task involves the expansion of an existing data base on mirror degradation due to environmental exposure and the collection of similar information on lenses. Status of the program is reported. (WHK)
Date: May 1, 1979
Partner: UNT Libraries Government Documents Department

Solar hot water systems for the southeastern United States: principles and construction of breadbox water heaters

Description: The use of solar energy to provide hot water is among the easier solar technologies for homeowners to utilize. In the Southeastern United States, because of the mild climate and abundant sunshine, solar energy can be harnessed to provide a household's hot water needs during the non-freezing weather period mid-April and mid-October. This workbook contains detailed plans for building breadbox solar water heaters that can provide up to 65% of your hot water needs during warm weather. If fuel costs continue to rise, the annual savings obtained from a solar water heater will grow dramatically. The designs in this workbook use readily available materials and the construction costs are low. Although these designs may not be as efficient as some commercially available systems, most of a household's hot water needs can be met with them. The description of the breadbox water heater and other types of solar systems will help you make an informed decision between constructing a solar water heater or purchasing one. This workbook is intended for use in the southeastern United States and the designs may not be suitable for use in colder climates.
Date: February 1, 1983
Partner: UNT Libraries Government Documents Department

Absorber coatings' degradation

Description: This report is intended to document some of the Los Alamos efforts that have been carried out under the Department of Energy (DOE) Active Heating and Cooling Materials Reliability, Maintainability, and Exposure Testing program. Funding for these activities is obtained directly from DOE although they represent a variety of projects and coordination with other agencies. Major limitations to the use of solar energy are the uncertain reliability and lifetimes of solar systems. This program is aimed at determining material operating limitations, durabilities, and failure modes such that materials improvements can be made and lifetimes can be extended. Although many active and passive materials and systems are being studied at Los Alamos, this paper will concentrate on absorber coatings and degradation of these coatings.
Date: January 1, 1984
Creator: Moore, S.W.
Partner: UNT Libraries Government Documents Department

Finite element strategies for the efficient analysis and evaluation of solar collector structures

Description: Concentrating or reflecting structures for solar energy systems must be evaluated as to their structural integrity and optical performance. Computer studies can be used as an integral part of these evaluations. The computer studies make use of finite element structural codes coupled with post-processors that calculate optical data. If the analysis of a solar structure is to be carried out in an efficient manner, these computer codes must have certain capabilities. A number of solar energy projects at Sandia National Laboratories have made extensive use of finite element analyses. The analyses have been useful in evaluating design concepts which hold promise for large scale use in solar energy projects. Analysis procedures have been developed for some structures so that evaluations can be carried out in a straightforward manner.
Date: January 1, 1980
Creator: Koteras, J. R.
Partner: UNT Libraries Government Documents Department

Simple design tool for sizing solar ponds

Description: This report presents a simple tool and method of analysis to aid practitioners in the planning and implementation of solar energy systems. This simple design tool for sizing solar ponds should aid analysts and planners in assessing the feasibility of solar ponds for any specified application, and in drawing up a preliminary plan for their implementation.
Date: December 1, 1979
Creator: Edesess, M.; Henderson, J. & Jayadev, T.S.
Partner: UNT Libraries Government Documents Department