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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 accuracy of an accompanying compliance calculation method and to help manufacturers find cost-effective ways to meet the new standard. Both homes performed within the standard without major design or production line modifications. Their performance fell within 8% of predictions based on the new draft HUD calculation manual; however, models with minimum window area were selected by the manufacturer. Models with more typical window area would have required substantive design changes to meet the standard. Several other tests were also performed on the homes by both NREL and the Florida Solar Energy Center (FSEC) to uncover potential thermal anomalies and to explore the degradation in thermal performance that might occur because of (a) penetrations in the rodent barrier from field hookups and repairs, (b) closing of interior doors with and without operation of the furnace blower, and (c) exposure to winds.
Date: June 1, 1992
Creator: Judkoff, R. D. & Barker, G. M.
Partner: UNT Libraries Government Documents Department

Uniform flux dish concentrators for photovoltaic application

Description: Researchers at the National Renewable Energy Laboratory (NREL) have designed a unique and innovative molded dish concentrator capable of producing a uniform flux profile on a flat target plane. Concentration levels of 100--200 suns, which are uniform over an area of several square inches, can be directly achieved for collection apertures of a reasonable size ({approximately}1.5-m diameter). Such performance would be immediately applicable to photovoltaic (PV) use. Economic concerns have shown that the proposed approach would be less expensive thatn Fresnel lens concepts or other dish concentrator designs that require complicated and costly receivers to mix the flux to obtain a uniform distribution. 12 refs.
Date: May 1, 1992
Creator: Jorgensen, G. & Wendelin, T.
Partner: UNT Libraries Government Documents Department

Wind Turbine Development: Press release

Description: The US Department of Energy (DOE) has announced a new partnership with Zond Systems, Inc., of Tehachapi, California. The partnership is the firs to be announced under DOE`s new Value-Engineered Turbine (VET) project. The VET project is expected to lower the cost of manufacturing wind turbines and give the US wind industry a competitive boost.
Date: May 9, 1994
Partner: UNT Libraries Government Documents Department

Photovoltaic Subcontract Program. Annual report, FY 1992

Description: This report summarizes the fiscal year (FY) 1992 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 United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.
Date: March 1, 1993
Partner: UNT Libraries Government Documents Department

Simplified air change effectiveness modeling

Description: This paper describes recent progress in developing practical air change effectiveness modeling techniques for the design and analysis of air diffusion in occupied rooms. The ultimate goal of this continuing work is to develop a simple and reliable method for determining heating, ventilating, and air-conditioning (HVAC) system compliance with ventilation standards. In the current work, simplified two-region models of rooms are used with six occupancy patterns to find the air change effectiveness. A new measure, the apparent ACH effectiveness, yields the relative ventilation performance of an air diffusion system. This measure can be used for the prediction or evaluation of outside air delivery to the occupants. The required outside air can be greater or less than that specified by ventilation standards such as ASHRAE Standard 62-89.
Date: June 1, 1992
Creator: Rock, B. A.; Anderson, R. & Brandemuehl, M. J.
Partner: UNT Libraries Government Documents Department

Solar synthesis of advanced materials: A solar industrial program initiative

Description: This is an initiative for accelerating the use of solar energy in the advanced materials manufacturing industry in the United States. The initiative will be based on government-industry collaborations that will develop the technology and help US industry compete in the rapidly expanding global advanced materials marketplace. Breakthroughs in solar technology over the last 5 years have created exceptional new tools for developing advanced materials. Concentrated sunlight from solar furnaces can produce intensities that approach those on the surface of the sun and can generate temperatures well over 2000{degrees}C. Very thin layers of illuminated surfaces can be driven to remarkably high temperatures in a fraction of a second. Concentrated solar energy can be delivered over large areas, allowing for rapid processing and high production rates. By using this technology, researchers are transforming low-cost raw materials into high-performance products. Solar synthesis of advanced materials uses bulk materials and energy more efficiently, lowers processing costs, and reduces the need for strategic materials -- all with a technology that does not harm the environment. The Solar Industrial Program has built a unique, world class solar furnace at NREL to help meet the growing need for applied research in advanced materials. Many new advanced materials processes have been successfully demonstrated in this facility, including the following: Metalorganic deposition, ceramic powders, diamond-like carbon materials, rapid heat treating, and cladding (hard coating).
Date: June 1, 1992
Creator: Lewandowski, A.
Partner: UNT Libraries Government Documents Department

Summary information and data sets for NREL`s Solar Radiation Research Laboratory, 1981--1991

Description: This report summarizes the solar radiation and meteorological data collected at the Solar Radiation Research Laboratory in Golden, Colorado, from 1981 through 1991. The data collection was part of the National Renewable Energy Laboratory`s Solar Radiation Resource Assessment Project. The report includes long-term averages and monthly and annual variability for key solar radiation elements and describes the hourly data sets for 1981 through 1991. Described in the report are how the elements were measured and how the data were collected and processed into hourly values. Procedures used for quality assessment of the hourly data values are presented, and the position of the solar radiation and meteorological elements in the data sets are defined; samples of read statements are provided.
Date: January 1, 1993
Creator: Marion, W.
Partner: UNT Libraries Government Documents Department

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 complies with the interpolation requirements; and finally (3) applying the bi-tension spline interpolation method, in the computational domain, to determine the coordinates of any point on the blade surface. Detailed descriptions of the overall approach to and philosophy of the code development are given along with the operation of the code. To show the usefulness of the bi-tension spline interpolation code developed, two examples are given, namely CARTER and MICON blade surface generation. Numerical results are presented in both graphic data forms. The solutions obtained in this work show that the computer code developed can be a powerful tool for generating the surface coordinates for any three-dimensional blade.
Date: May 1, 1992
Creator: Yang, S. L.; Oryang, D. & Ho, M. J.
Partner: UNT Libraries Government Documents Department

Non-CFC air conditioning for transit buses

Description: In the United Sates, more than 80% of transit city buses are air conditioned. Vapor compression refrigeration systems are standard for air conditioning buses and account for up to 25% of fuel consumption in the cooling season. Vapor compression devices use chlorofluorocarbons (CFCs), chemicals that contributes to Earths`s ozone depletion and to global warming. Currently, evaporative cooling is an economical alternative to CFC vapor compression refrigeration for air conditioning buses. It does not use CFCs but is restricted in use to arid climates. This limitation can be eliminated by dehumidifying the supply air using desiccants. We studied desiccant systems for cooling transit buses and found that the use of a desiccant-assisted evaporative cooling system is feasible and can deliver the required cooling. The weight and the size of the desiccant system though larger than vapor compression systems, can be easily accommodated within a bus. Fuel consumption for naming desiccant systems was about 70% less than CFC refrigeration system, resulting in payback periods of less than 2.5 years under most circumstances. This preliminary study indicated that desiccant systems combined with evaporative cooling is a CFC-free option to vapor compression refrigeration for air conditioning of transit buses. The concept is ready to be tested in a fun prototype scale in a commercial bus.
Date: November 1, 1992
Creator: Pesaran, A. A.; Parent, Y. O. & Bharathan, D.
Partner: UNT Libraries Government Documents Department

NREL PV AR&D 11th review meeting, May 13--15, 1992, Denver Marriott City Center, Denver, Colorado. Photovoltaic Advanced Research and Development Project

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: June 1, 1992
Partner: UNT Libraries Government Documents Department

Fuel savings and emissions reductions from light duty fuel cell vehicles

Description: Fuel cell vehicles (FCVs) operate efficiently, emit few pollutants, and run on nonpetroleum fuels. Because of these characteristics, the large-scale deployment of FCVs has the potential to lessen US dependence on foreign oil and improve air quality. This study characterizes the benefits of large-scale FCV deployment in the light duty vehicle market. Specifically, the study assesses the potential fuel savings and emissions reductions resulting from large-scale use of these FCVs and identifies the key parameters that affect the scope of the benefits from FCV use. The analysis scenario assumes that FCVs will compete with gasoline-powered light trucks and cars in the new vehicle market for replacement of retired vehicles and will compete for growth in the total market. Analysts concluded that the potential benefits from FCVs, measured in terms of consumer outlays for motor fuel and the value of reduced air emissions, are substantial.
Date: April 1, 1994
Creator: Mark, J.; Ohi, J. M. & Hudson, D. V. Jr.
Partner: UNT Libraries Government Documents Department

FY 1992 Measurements and Characterization Branch annual report

Description: The Measurements and Characterization Branch actively supports the advancement of DOE/NREL goals for the development and implementation of the solar photovoltaic (PV) technology. The primary focus of the laboratories is to provide state-of-the-art analytical capabilities for materials and device characterization and fabrication. The branch houses a comprehensive facility that Is capable of providing information on the full range of PV components. A major objective of the branch is to aggressively pursue collaborative research with other government laboratories, universities, and industrial firms for the advancement of Pv technologies. Members of the branch disseminate research findings to the technical community in publications and presentations. The Measurements and Characterization Branch encompasses seven coordinated research groups, providing integrated research and development that covers all aspects of photovoltaic materials/devices characterization.
Date: March 1, 1993
Creator: Dippo, P. C
Partner: UNT Libraries Government Documents Department

Investigation of polycrystalline thin-film CuInSe{sub 2} solar cells based on ZnSe windows. Annual subcontract report, 15 Febraury 1992--14 February 1993

Description: Investigations of ZnSe/CIS solar cells are being carried out in an effort to improve the efficiencies CIS cells and to determine if ZnSe is a viable alternative to CdS as a window material. MOCVD growth of ZnSe is accomplished in a SPIRE 500XT reactor housed in the Electronic Materials Laboratory at WSU Tri-Cities by reacting a zinc adduct with H{sub 2}Se. Conductive n-type ZnSe is grown by using iodine as a dopant. Ethyliodide was mixed with helium and installed on one of the gas lines to the system. ZnSe films have been grown on CIS substrates at 200{degrees}C to 250{degrees}C. ZnO is also being deposited by MOCVD by reacting tetrahydrofuran (THF) with a zinc adduct. ZnSe/CIS heterojunctions have been studied by growing n-ZnSe films onto 2 cm x 2 cm CIS substrates diced from materials supplied by Siemens and then depositing an array of aluminum circular areas 2.8.mm in diameter on top of the ZnSe to serve as contacts. Al films are deposited with a thickness of 80 to l00 {angstrom}so that light can pass through the film, thus allowing the illuminated characteristics of the ZnSe/CIS junction to be tested. Accounting for the 20 to 25 % transmittance through the Al film into the ZnSe/CIS structure, current devices have estimated, active-area AM1.5 efficiencies of 14 %. Open circuit voltages > 500 mV are often attained.
Date: May 1, 1994
Creator: Olsen, L C
Partner: UNT Libraries Government Documents Department

US manufacturers of commercially available stand-alone photovoltaic lighting systems

Description: This report introduces photovoltaic (PV) lighting systems, gives some specifications for ordering these systems, and provides a list of some of the manufacturers of these systems in the United States. These PV lighting systems are all commercially available. They are stand-alone systems because they are not tied to the electric utility power grid.
Date: May 1, 1994
Creator: McNutt, P.
Partner: UNT Libraries Government Documents Department

Wind Energy Program overview, Fiscal year 1993

Description: Wind energy research has two goals: (1) to gain a fundamental understanding of the interactions between wind and wind turbines; and (2) to develop the basic design tools required to develop advanced technologies. A primary objective of applied research activities is to develop sophisticated computer codes and integrate them into the design, testing, and evaluation of advanced components and systems, Computer models have become a necessary and integral part of developing new high-tech wind energy systems. A computer-based design strategy allows designers to model different configurations and explore new designs before building expensive hardware. DOE works closely with utilities and the wind industry in setting its applied research agenda. As soon as research findings become available, the national laboratories transfer the information to industry through workshops, conferences, and publications.
Date: May 1, 1994
Partner: UNT Libraries Government Documents Department

Sterilization of fermentation vessels by ethanol/water mixtures

Description: This invention is comprised of a method for sterilizing process fermentation vessels with a concentrated alcohol and water mixture integrated in a fuel alcohol or other alcohol production facility. Hot, concentrated alcohol is drawn from a distillation or other purification stage and sprayed into the empty fermentation vessels. This sterilizing alcohol/water mixture should be of a sufficient concentration, preferably higher than 12% alcohol by volume, to be toxic to undesirable microorganisms. Following sterilization, this sterilizing alcohol/water mixture can be recovered back into the same distillation or other purification stage from which it was withdrawn. The process of this invention has its best application in, but is not limited to, batch fermentation processes, wherein the fermentation vessels must be emptied, cleaned, and sterilized following completion of each batch fermentation process.
Date: March 20, 1991
Creator: Wyman, C. E.
Partner: UNT Libraries Government Documents Department

Use of infra-red thermography for automotive climate control analysis

Description: In this paper, several automotive climate control applications for IR thermography are described. Some of these applications can be performed using conventional IR techniques. Others, such as visualizing the air temperature distribution within the cabin, at duct exits, and at heater and evaporator faces, require new experimental methods. In order to capture the temperature distribution within an airstream, a 0.25-mm-thick (0.01 inch) fiberglass screen is used. This screen can be positioned perpendicular or parallel to the flow to obtain three-dimensional spatial measurements. In many cases, the air flow pattern can be inferred from the resulting temperature distribution, allowing improved air distribution designs. In all cases, significant improvement in the speed, ease, and quantity of temperature distribution information can be realized with thermography as compared to conventional thermocouple array techniques. Comparisons are presented between IR thermography images and both thermocouple measurements and computational fluid dynamics (CFD) predictions.
Date: March 1, 1994
Creator: Burch, S. D.; Hassani, V. & Penney, T. R.
Partner: UNT Libraries Government Documents Department

Trends in public perceptions and preferences on energy and environmental policy

Description: This report presents selected results from a secondary analysis of public opinion surveys, taken at the national and state/local levels, relevant to energy and environmental policy choices. The data base used in the analysis includes about 2000 items from nearly 600 separate surveys conducted between 1979 and 1992. Answers to word-for-word questions were traced over time, permitting trend analysis. Patterns of response were also identified for findings from similarly worded survey items. The analysis identifies changes in public opinion concerning energy during the past 10 to 15 years.
Date: February 1, 1993
Creator: Farhar, B. C.
Partner: UNT Libraries Government Documents Department

Wind/hybrid power system test facilities in the United States and Canada

Description: By 1995, there will be four facilities available for testing of wind/hybrid power systems in the United States and Canada. This paper describes the mission, approach, capabilities, and status of activity at each of these facilities. These facilities have in common a focus on power systems for remote, off-grid locations that include wind energy. At the same time, these facilities have diverse, yet complimentary, missions that range from research to technology development to testing. The first facility is the test facility at the Institut de Recherche d`Hydro-Quebec (IREQ), Hydro-Quebec`s research institute near Montreal, Canada. This facility, not currently in operation, was used for initial experiments demonstrating the dynamic stability of a high penetration, no-storage wind/diesel (HPNSWD) concept. The second facility is located at the Atlantic Wind Test Site (AWTS) on Prince Edward Island, Canada, where testing of the HPNSWD concept developed by Hydro-Quebec is currently underway. The third is the Hybrid Power Test Facility planned for the National Wind Technology Center at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, which will focus on testing commercially available hybrid power systems. The fourth is the US Department of Agriculture (USDA) Conservation and Production Research Laboratory in Bushland, Texas, where a test laboratory is being developed to study wind-energy penetration and control strategies for wind/hybrid systems. The authors recognize that this summary of test facilities is not all inclusive; for example, at least one US industrial facility is currently testing a hybrid power system. Our intent, though, is to describe four facilities owned by nonprofit or governmental institutions in North America that are or will be available for ongoing development of wind/hybrid power systems.
Date: May 1, 1994
Creator: Green, H J; Clark, R N; Brothers, C & Saulnier, B
Partner: UNT Libraries Government Documents Department

Study of parameters affecting the performance of solar desiccant cooling systems

Description: The performance of a solar desiccant cooling system depends on the performance of its components, particularly the desiccant dehumidifier and solar collectors. The desiccant dehumidifier performance is affected by the properties of the desiccant, particularly the shape of the isotherm and the regeneration temperature. The performance of a solar collector, as one would expect, depends on its operating temperature, which is very close to the desiccant regeneration temperature. The purpose of this study was to identify the desiccant isotherm shape (characterized by separation factor) that would result in the optimum performance - based on thermal coefficient of performance and cooling capacity - of a desiccant cooling cycle operating in ventilation mode. Different regeneration temperatures ranging from 65{degree}C to 160{degree}C were investigated to identify the corresponding optimum isotherm shape at each. Thermal COP dictates the required area of the solar collectors, and the cooling capacity is an indication of the size and cost of the cooling equipment. Staged and no-staged regeneration methods were studied.
Date: January 1, 1993
Creator: Pesaran, A. A. & Hoo, E. A.
Partner: UNT Libraries Government Documents Department

Outdoor testing of advanced optical materials for solar thermal electric applications

Description: The development of low-cost, durable advanced optical materials is an important element in making solar energy viable for electricity production. It is important to determine the expected lifetime of candidate reflector materials in real-world service conditions. The demonstration of the optical durability of such materials in outdoor environments is critical to the successful commercialization of solar thermal electric technologies. For many years optical performance data have been collected and analyzed by the National Renewable Energy Laboratory (NREL) for candidate reflector materials subjected to simulated outdoor exposure conditions. Much of this testing is accelerated in order to predict service durability. Some outdoor testing has occurred but not in a systematic manner. To date, simulated/accelerated testing has been limited correlation with actual outdoor exposure testing. Such a correlation is desirable to provide confidence in lifetime predictions based upon accelerated weathering methods. To obtain outdoor exposure data for realistic environments and to establish a data base for correlating simulated/accelerated outdoor exposure data with actual outdoor exposure data, the development of an expanded outdoor testing program has recently been initiated by NREL. Several outdoor test sites will be selected based on the solar climate, potential for solar energy utilization by industry, and cost of installation. Test results are site dependent because exposure conditions vary with geographical location. The importance of this program to optical materials development is outlined, and the process used to determine and establish the outdoor test sites is described. Candidate material identification and selection is also discussed. 10 refs.
Date: May 1992
Creator: Wendelin, T. J.; Jorgensen, G. & Goggin, R. M.
Partner: UNT Libraries Government Documents Department

Photovoltaic Subcontract Program, FY 1991. Annual report, [October 1, 1990--September 30, 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 United States. The technical sections of the report cover the main areas of the subcontract program: the Amorphous Silicon Research Project, Polycrystalline Thin Films, Crystalline Silicon Materials Research, High-Efficiency Concepts, the New Ideas Program, the University Participation Program, and the Photovoltaic Manufacturing Technology (PVMaT) project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1991, and future research directions.
Date: March 1, 1992
Partner: UNT Libraries Government Documents Department

Photovoltaics: Program overview fiscal year 1993

Description: This overview is divided into sections titled: 1993 PV program accomplishments, PV systems for today`s markets generate power and experience, systems development and testing prepares products for market, advances in manufacturing hasten availability of innovations, cooperative research improves PV technology, additional achievements in cooperative R&D, and summary of PV program services. Figs, tabs.
Date: February 1, 1994
Partner: UNT Libraries Government Documents Department

Photovoltaics for municipal planners. Cost-effective municipal applications of photovoltaics for electric power

Description: This booklet is intended for city and county government personnel, as well as community organizations, who deal with supplying, regulating, or recommending electric power resources. Specifically, this document deals with photovoltaic (PV) power, or power from solar cells, which is currently the most cost-effective energy source for electricity requirements that are relatively small, located in isolated areas, or difficult to serve with conventional technology. Recently, PV has been documented to be more cost-effective than conventional alternatives (such as line extensions or engine generators) in dozens of applications within the service territories of electric, gas, and communications utilities. Here, we document numerous cost-effective urban applications, chosen by planners and utilities because they were the most cost-effective option or because they were appropriate for environmental or logistical reasons. These applications occur within various municipal departments, including utility, parks and recreation, traffic engineering, transportation, and planning, and they include lighting applications, communications equipment, corrosion protection, irrigation control equipment, remote monitoring, and even portable power supplies for emergency situations.
Date: April 1, 1993
Partner: UNT Libraries Government Documents Department