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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

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

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

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

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

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

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

Thermal performance evaluation of the Northrup Model NSC-01-0732 concentrating solar collector array at outdoor conditions

Description: The thermal performance tests conducted on the Northrup Model NSC-01-0732 concentrating, tracking solar collector for approximately two months (from the end of August to the first part of October 1979) are described. These tests were made using the Marshall Space Flight Center's Solar House Test Facility.
Date: December 1, 1979
Partner: UNT Libraries Government Documents Department

Development and testing of the Solar Control Corporation modular Controller and Solarstat Subsystem. Final report

Description: This document summarizes the final results of contract NAS8-32258 Solar Control Corporation, for the additional development work on their existing Controller and Solarstat Subsystem for use with solar heating and cooling systems. It discusses the intended use of the final report, describes the deliverable end items, lists program objectives, and relates how they were accomplished. The report shows that the products developed are marketable and suitable for public use.
Date: August 1, 1979
Creator: Hankins, J.D.
Partner: UNT Libraries Government Documents Department

Development and testing of the Sunkeeper Control Corporation integrated programmable electronic controller and hydronics package. Final report

Description: This document summarizes the final results of contract NAS8-32257 with Sunkeeper Control Corporation (now Andover Controls) of Andover, Massachusetts for the additional development work on their existing programmable electronic controller and hydronic package for use with solar heating and cooling systems. It discusses the intended use of the final report, describes the deliverable end items, lists program objectives and relates how they were accomplished. The report shows that the products developed are marketable and suitable for public use.
Date: January 1, 1979
Creator: Hankins, J.D
Partner: UNT Libraries Government Documents Department

Freeze-protection loop for direct solar-water-heating systems. Final report

Description: Even a one-time freeze condition can do destructive damage to a direct solar water heating system. The project funded under grant DE-FG4480R4, 1-1-80 to 8-1-81, proposed to demonstrate a simple installation procedure whereby thermosiphoning warm water from storage would prevent solar collectors from freezing. Installing the freeze protection loop in owner maintained solar systems was inconclusive. Owners were not attentive to freeze warnings or did not understand the simple instructions. A controlled situation was established using a refrigerator to produce below freezing temperatures. Experiments conducted with this equipment showed that the thermosiphoning principle could not be relied on to prevent freezing. Thermosiphoning cannot be relied on to prevent freezing in a direct solar water heating system. The direct system is an effective means of heating water in north Florida, but the system must be drained, either manually or automatically, to provide reliable system protection.
Date: November 4, 1981
Partner: UNT Libraries Government Documents Department

Solar still. Final report

Description: Passive solar heating was used in a still in which a packed column packed with popped popcorn separates the alcohol and water vapors. The still's performance was not satisfactory, and it is concluded that passive solar heating could have been better used to preheat makeup water for the fermentation process and to maintain proper fermentation temperatures during the winter. (LEW)
Date: July 20, 1983
Creator: Adams, W.D.
Partner: UNT Libraries Government Documents Department

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

Description: Construction of the components of an automated solar cell layup and interconnect system is now complete. This system incorporates a Unimate 2000 B industrial robot with an end effector consisting of a vacuum pick up and induction heating coil. The robot interfaces with a smart cell preparation station which correctly orients the cell, applies solder paste and forms and positions the correct lengths of interconnect lead. The system is controlled and monitored by a TRS-80 micro computer. The entire system is presently undergoing integration prior to formal testing. A survey of elastomer manufacturers has shown transfer molded EPDM to be a strong candidate for the edge sealing material.
Date: October 15, 1979
Creator: Hagerty, J.J.
Partner: UNT Libraries Government Documents Department

ASHMET: a computer code for estimating insolation incident on tilted surfaces

Description: A computer code, ASHMET, has been developed by MSFC to estimate the amount of solar insolation incident on the surfaces of solar collectors. Both tracking and fixed-position collectors have been included. Climatological data for 248 US locations are built into the code. This report describes the methodology of the code, and its input and output. The basic methodology used by ASHMET is the ASHRAE clear-day insolation relationships modified by a clearness index derived from SOLMET-measured solar radiation data to a horizontal surface.
Date: May 1, 1980
Creator: Elkin, R.F. & Toelle, R.G.
Partner: UNT Libraries Government Documents Department

Windjammer solar-water-heating system. Final technical report

Description: The results of the Windjammer Solar-Water-Heating System tests showed that it was not as an efficient system as a comparable conventional system for converting solar energy into heat energy. However, it was determined that the innovative mode used less electric back-up energy for water heating. Reduced fossil fuel energy consumption being the ultimate objective of a solar water heating, the principle employed has been shown to be a workable energy saving concept. The differential mode of temperature control emerged as the more efficient mode of operation for the innovative system and under comparable conditions is projected to be nearly equivalent to the conventional solar system. Although the concept has proven workable, the costs feasible, and the potential for considereable improvements exists, additional research and development is needed to advance the design into its most practical application.
Date: April 1, 1982
Creator: Windham, J.R.
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