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Sample records for advanced residential solar

  1. Residential Solar Systems.

    ERIC Educational Resources Information Center

    Fulkerson, Dan

    This publication contains student and teacher instructional materials for a course in residential solar systems. The text is designed either as a basic solar course or as a supplement to extend student skills in areas such as architectural drafting, air conditioning and refrigeration, and plumbing. The materials are presented in four units…

  2. Advancing Residential Energy Retrofits

    SciTech Connect

    Jackson, Roderick K; Boudreaux, Philip R; Kim, Eyu-Jin; Roberts, Sydney

    2012-01-01

    To advance the market penetration of residential retrofits, Oak Ridge National Laboratory (ORNL) and Southface Energy Institute (Southface) partnered to provide technical assistance on nine home energy retrofits in metropolitan Atlanta with simulated source energy savings of 30% to 50%. Retrofit measures included duct sealing, air infiltration reductions, attic sealing and roofline insulation, crawlspace sealing, HVAC and water heating equipment replacement, and lighting and appliance upgrades. This paper will present a summary of these measures and their associated impacts on important home performance metrics, such as air infiltration and duct leakage. The average estimated source energy savings for the homes is 33%, and the actual heating season average savings is 32%. Additionally, a case study describing expected and realized energy savings of completed retrofit measures of one of the homes is described in this paper.

  3. Solar photovoltaic residential project

    NASA Astrophysics Data System (ADS)

    1981-10-01

    Progress with technology transfer and the performance of photovoltaic power supplies in Northeastern and Southwestern residences are reported. Also, systems operation in Florida and Hawaii are discussed briefly. Technology development in the field of power conditioning and flywheel storage is described. Work on some non-residential field tests is also described. Project management data are summarized.

  4. Residential solar-heating system

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Complete residential solar-heating and hot-water system, when installed in highly-insulated energy-saver home, can supply large percentage of total energy demand for space heating and domestic hot water. System which uses water-heating energy storage can be scaled to meet requirements of building in which it is installed.

  5. Advanced phase change materials and systems for solar passive heating and cooling of residential buildings

    SciTech Connect

    Salyer, I.O.; Sircar, A.K.; Dantiki, S.

    1988-01-01

    During the last three years under the sponsorship of the DOE Solar Passive Division, the University of Dayton Research Institute (UDRI) has investigated four phase change material (PCM) systems for utility in thermal energy storage for solar passive heating and cooling applications. From this research on the basis of cost, performance, containment, and environmental acceptability, we have selected as our current and most promising series of candidate phase change materials, C-15 to C-24 linear crystalline alkyl hydrocarbons. The major part of the research during this contract period was directed toward the following three objectives. Find, test, and develop low-cost effective phase change materials (PCM) that melt and freeze sharply in the comfort temperature range of 73--77{degree}F for use in solar passive heating and cooling of buildings. Define practical materials and processes for fire retarding plasterboard/PCM building products. Develop cost-effective methods for incorporating PCM into building construction materials (concrete, plasterboard, etc.) which will lead to the commercial manufacture and sale of PCM-containing products resulting in significant energy conservation.

  6. Residential solar home resale analysis

    SciTech Connect

    Noll, S.A.

    1980-01-01

    One of the determinants of the market acceptance of solar technologies in the residential housing sector is the value placed upon the solar property at the time of resale. The resale factor is shown to be an important economic parameter when net benefits of the solar design are considered over a typical ownership cycle rather than the life cycle of the system. Although a study of solar resale in Davis, Ca, indicates that those particular homes have been appreciating in value faster than nonsolar market comparables, no study has been made that would confirm this conclusion for markets in other geograhical locations with supporting tests of statistical significance. The data to undertake such an analysis is available through numerous local sources; however, case by case data collection is prohibitively expensive. A recommended alternative approach is to make use of real estate market data firms who compile large data bases and provide multi-variate statistical analysis packages.

  7. Solar residential heating and cooling system

    NASA Technical Reports Server (NTRS)

    Melton, D. E.; Humphries, W. R.

    1975-01-01

    System has been placed in operation to verify technical feasibility of using solar energy to provide residential heating and cooling. Complete system analysis was performed to provide design information.

  8. Forecasting Residential Solar Photovoltaic Deployment in California

    SciTech Connect

    Dong, Changgui; Sigrin, Benjamin; Brinkman, Gregory

    2016-12-06

    Residential distributed photovoltaic (PV) deployment in the United States has experienced robust growth, and policy changes impacting the value of solar are likely to occur at the federal and state levels. To establish a credible baseline and evaluate impacts of potential new policies, this analysis employs multiple methods to forecast residential PV deployment in California, including a time-series forecasting model, a threshold heterogeneity diffusion model, a Bass diffusion model, and National Renewable Energy Laboratory's dSolar model. As a baseline, the residential PV market in California is modeled to peak in the early 2020s, with a peak annual installation of 1.5-2 GW across models. We then use the baseline results from the dSolar model and the threshold model to gauge the impact of the recent federal investment tax credit (ITC) extension, the newly approved California net energy metering (NEM) policy, and a hypothetical value-of-solar (VOS) compensation scheme. We find that the recent ITC extension may increase annual PV installations by 12%-18% (roughly 500 MW, MW) for the California residential sector in 2019-2020. The new NEM policy only has a negligible effect in California due to the relatively small new charges (< 100 MW in 2019-2020). Furthermore, impacts of the VOS compensation scheme ($0.12 per kilowatt-hour) are larger, reducing annual PV adoption by 32% (or 900-1300 MW) in 2019-2020.

  9. Prototype residential solar-energy system

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Complete solar-energy domestic-hot-water system for single-family residences is described in brochure. It contains data on procurement, installation, operation, and maintainance of system in residential or light commercial buildings. Appendix includes vendor brochures for major system components. Drawings, tables, and graphs complement text.

  10. Solar Energy Systems for Ohioan Residential Homeowners

    NASA Astrophysics Data System (ADS)

    Luckett, Rickey D.

    Dwindling nonrenewable energy resources and rising energy costs have forced the United States to develop alternative renewable energy sources. The United States' solar energy industry has seen an upsurge in recent years, and photovoltaic holds considerable promise as a renewable energy technology. The purpose of this case study was to explore homeowner's awareness of the benefits of solar energy. Disruptive-innovation theory was used to explore marketing strategies for conveying information to homeowners about access to new solar energy products and services. Twenty residential homeowners were interviewed face-to-face to explore (a) perceived benefits of solar energy in their county in Ohio, and (b) perceptions on the rationale behind the marketing strategy of solar energy systems sold for residential use. The study findings used inductive analyses and coding interpretation to explore the participants' responses that revealed 3 themes: the existence of environmental benefits for using solar energy systems, the expensive cost of equipment associated with government incentives, and the lack of marketing information that is available for consumer use. The implications for positive social change include the potential to enable corporate leaders, small business owners, and entrepreneurs to develop marketing strategies for renewable energy systems. These strategies may promote use of solar energy systems as a clean, renewable, and affordable alternative electricity energy source for the 21st century.

  11. Solar Photovoltaic Financing: Residential Sector Deployment

    SciTech Connect

    Coughlin, J.; Cory, K.

    2009-03-01

    This report presents the information that homeowners and policy makers need to facilitate PV financing at the residential level. The full range of cash payments, bill savings, and tax incentives is covered, as well as potentially available solar attribute payments. Traditional financing is also compared to innovative solutions, many of which are borrowed from the commercial sector. Together, these mechanisms are critical for making the economic case for a residential PV installation, given its high upfront costs. Unfortunately, these programs are presently limited to select locations around the country. By calling attention to these innovative initiatives, this report aims to help policy makers consider greater adoption of these models to benefit homeowners interested installing a residential PV system.

  12. Economic analysis of residential solar water heaters

    SciTech Connect

    1980-09-23

    A typical residential solar water heater, and typical cost and performance information are described briefly. The monthly costs and savings of the typical system are discussed. Economic evaluations of solar water heaters are presented in increasingly complex levels of detail. Utilizing a typical system, the effective interest rate that the purchaser of a system would receive on money invested is shown for all regions of the country. The importance of numerous variables that can make a significant difference on the economics of the system is described. Methods for calculating the Payback Period for any non-typical solar water heater are described. This calculated Payback Period is then shown to be related to the effective interest rate that the puchaser of the system would receive for a typical set of economic conditions. A method is presented to calculate the effective interest rate that the solar system would provide. (MHR)

  13. Evaluation of residential and commercial solar/gas heating and cooling technologies. Volume 1: Program overview

    NASA Astrophysics Data System (ADS)

    Hirshberg, A. S.; Haas, S. A.; Jacobsen, A. S.

    1980-12-01

    The technologies and economics of solar/gas systems for application in the single-family residential market and in the small (individual building) commerical market were evaluated. The effects of solar industry maturity on system cost and the impact of solar incentives and natural gas price uncertainties on solar/gas system economics were studied. Projected solar/gas systems with advanced conventional gas equipment such as pulse combustion furnaces are discussed.

  14. Solar preheater for residential heat pumps

    SciTech Connect

    1983-01-01

    The Solar Preheater for Residential Heat PUmps was designed to offset the weakest points in a heat pump system using solar energy. These weak points affect both energy efficiency and comfort, and are: (1) the heat pumps need to defrost its outside coils, and (2) its use of resistance coils when outside air is very cold. While a heat pump can claim close to 100% efficiency in its conversion of electricity to heat, these efficiencies drop way off under the above circumstances. Less dramatic energy savings should also occur during the heat pump's normal operation, since a heat pump takes available heat and condenses it to heat the house. It seems reasonable to say that if there is more heat in the outside air it will take less time to raise the temperature inside. The net effect should be similar to having the heat pump located several hundred miles south of the home it is heating. There are several ways to achieve solar augmentation of heat pump operation, but most are either too expensive, too difficult for do-it-yourselfers, or are not easily adaptable to existing units. The solar preheater for residential heat pumps gets around all the above restrictions.

  15. Residential Solar Power and the Physics Teacher

    NASA Astrophysics Data System (ADS)

    Carpenter, David

    2007-10-01

    The roof of my house sports one of the largest residential photovoltaic arrays in Ohio. It produces all of the electricity for my house and family of four. With state and federal incentives, it cost less to install than the price of a new car. It will pay for itself within the warrantee period. A picture of my house with solar panels is the background on my classroom computer. I am the physics teacher at Hayes High School in Delaware, Ohio. I don't need a formal curriculum. Sooner or later my students start asking questions. They even ask the exact same questions that adults do. The inverter for my PV system sends performance data to my computer. I post this on my website, which takes it into my classroom. This sparks conversation on a whole variety of topics, from sun angles to energy, electricity, technology and climate studies.

  16. Prototype residential solar-energy system-design package

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Compilation includes documents and drawings for complete solar-heating system. It discussed system installed in residential building at Veterns' Administration Hospital in Togus, Maine. System can be adapted to other buildings without changing design.

  17. Advanced solar dynamic technology program

    NASA Technical Reports Server (NTRS)

    Calogeras, James

    1990-01-01

    Viewgraphs and discussion on Advanced Solar Dynamic Technology Program are presented. Topics covered include: advanced solar dynamic technology program; advanced concentrators; advanced heat receivers; power conversion systems; dished all metal honeycomb sandwich panels; Stirling cavity heat pipe receiver; Brayton solar receiver; and thermal energy storage technology.

  18. Cooling-load implications for residential passive solar heating systems

    NASA Astrophysics Data System (ADS)

    Jones, R. W.; McFarland, R. D.

    1983-11-01

    The quantification of cooling loads in residential buildings, particularly buildings with passive solar heating systems, is described, along with the computer simulation model used for calculating cooling loads. A sample of interim results is also presented. The objective of the research is to develop a simple analysis method, useful early in the design, to estimate the annual cooling energy requirement of a given building.

  19. Residential solar photovoltaic systems: Final report for the Northeast Residential Experiment Station

    SciTech Connect

    Kern, E.C. Jr.

    1986-06-01

    This report covers research and development work conducted by the MIT Energy Lab. from July 1982 through June 1986. This Energy Lab. work in the field of solar photovoltaic systems followed six years of similar work at the MIT Lincoln Lab. under the same contract with the US DOE. The final report from the Lincoln Lab. period was published by Lincoln Lab. in 1983. During the period of Energy Lab. involvement, the project focused on the refinement of residential scale, roof-mounted photovoltaic systems for application in the northeastern US. Concurrent with the conclusion of MIT`s involvement, the New England Electric Co. is building a major field test of residential photovoltaics in Gardner, Massachusetts to determine experimentally the effects of photovoltaics on electric power company operations. Using systems designs and technology developed at MIT, the long-term performance of these thirty residential systems in Gardner will provide a measure of our success.

  20. Advanced Solar Power Systems

    NASA Technical Reports Server (NTRS)

    Atkinson, J. H.; Hobgood, J. M.

    1984-01-01

    The Advanced Solar Power System (ASPS) concentrator uses a technically sophisticated design and extensive tooling to produce very efficient (80 to 90%) and versatile energy supply equipment which is inexpensive to manufacture and requires little maintenance. The advanced optical design has two 10th order, generalized aspheric surfaces in a Cassegrainian configuration which gives outstanding performance and is relatively insensitive to temperature changes and wind loading. Manufacturing tolerances also have been achieved. The key to the ASPS is the direct absorption of concentrated sunlight in the working fluid by radiative transfers in a black body cavity. The basic ASPS design concepts, efficiency, optical system, and tracking and focusing controls are described.

  1. Residential Solar Design Review: A Manual on Community Architectural Controls and Solar Energy Use.

    ERIC Educational Resources Information Center

    Jaffe, Martin; Erley, Duncan

    Presented are architectural design issues associated with solar energy use, and procedures for design review committees to consider in examining residential solar installation in light of existing aesthetic goals for their communities. Recommended design review criteria include the type of solar system being used and the ways in which the system…

  2. Residential solar-heating system - design brochure

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Design brochure for commercially-available solar-heating system is valuable to architects, engineers, and designers. It contains information on system configuration, system sizing, and mechanical layout. Drawings and specifications of all components and typical installation details are included in appendix.

  3. Development of a solar-powered residential air conditioner

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The initial objective of the program was the optimization (in terms of cost and performance) of a Rankine cycle mechanical refrigeration system which utilizes thermal energy from a flat solar collector for air conditioning residential buildings. However, feasibility investigations of the adsorption process revealed that a dessicant-type air conditioner offers many significant advantages. As a result, limited efforts were expended toward the optimization of such a system.

  4. Advanced solar panel designs

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.; Linder, E.

    1995-01-01

    This paper describes solar cell panel designs that utilize new hgih efficiency solar cells along with lightweight rigid panel technology. The resulting designs push the W/kg and W/sq m parameters to new high levels. These new designs are well suited to meet the demand for higher performance small satellites. This paper reports on progress made on two SBIR Phase 1 contracts. One panel design involved the use of large area (5.5 cm x 6.5 cm) GaAs/Ge solar cells of 19% efficiency combined with a lightweight rigid graphite fiber epoxy isogrid substrate configuration. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power level of 60 W/kg with a potential of reaching 80 W/kg. The second panel design involved the use of newly developed high efficiency (22%) dual junction GaInP2/GaAs/Ge solar cells combined with an advanced lightweight rigid substrate using aluminum honeycomb core with high strength graphite fiber mesh facesheets. A coupon (38 cm x 38 cm) was fabricated and tested which demonstrated an array specific power of 105 W/kg and 230 W/sq m. This paper will address the construction details of the panels and an a analysis of the component weights. A strawman array design suitable for a typical small-sat mission is described for each of the two panel design technologies being studied. Benefits in respect to weight reduction, area reduction, and system cost reduction are analyzed and compared to conventional arrays.

  5. System integration issues of residential solar photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Yamayee, Z. A.; Peschon, J.

    1980-03-01

    The economic effects of residential solar PV systems on the utility's revenue, capacity, and energy requirements from the electric utility's perspective are evaluated. The price that it might pay for surplus energy and what it would charge for deficits are compared. The power and energy generated by the solar PV systems reduce the capital and operating costs that would otherwise be incurred by the utility. These avoided costs suggest what the utility might pay for surplus solar PV energy. The avoided costs are evaluated under three integration hypotheses, namely: (1) the utility has no system storage; (2) the utility has system storage; and (3) the solar PV systems are supported by dedicated storage devices, the purpose of which is to minimize sales to and purchases from the utility.

  6. Empirically Derived Strength of Residential Roof Structures for Solar Installations.

    SciTech Connect

    Dwyer, Stephen F.; Sanchez, Alfred; Campos, Ivan A.; Gerstle, Walter H.

    2014-12-01

    Engineering certification for the installation of solar photovoltaic (PV) modules on wood roofs is often denied because existing wood roofs do not meet structural design codes. This work is intended to show that many roofs are actually sufficiently strong given the conservatism in codes, documented allowable strengths, roof structure system effects, and beam composite action produced by joist-sheathing interaction. This report provides results from a testing program to provide actual load carrying capacity of residential rooftops. The results reveal that the actual load carrying capacity of structural members and systems tested are significantly stronger than allowable loads provided by the International Residential Code (IRC 2009) and the national structural code found in Minimum Design Loads for Buildings and Other Structures (ASCE 7-10). Engineering analysis of residential rooftops typically ignores the system affects and beam composite action in determining rooftop stresses given a potential PV installation. This extreme conservatism combined with conservatism in codes and published allowable stress values for roof building materials (NDS 2012) lead to the perception that well built homes may not have adequate load bearing capacity to enable a rooftop PV installation. However, based on the test results presented in this report of residential rooftop structural systems, the actual load bearing capacity is several times higher than published values (NDS 2012).

  7. Solar Adoption and Energy Consumption in the Residential Sector

    NASA Astrophysics Data System (ADS)

    McAllister, Joseph Andrew

    This dissertation analyzes the energy consumption behavior of residential adopters of solar photovoltaic systems (solar-PV). Based on large data sets from the San Diego region that have been assembled or otherwise acquired by the author, the dissertation quantifies changes in energy consumption after solar-PV installation and determines whether certain household characteristics are correlated with such changes. In doing so, it seeks to answer two related questions: First, "Do residential solar adopters increase or decrease their electricity consumption after they install a solar-PV system?" Assuming that certain categories of residential adopters increase and others decrease, the second question is "Which residential adopters increase and which decrease their consumption and why?" The database that was used to conduct this analysis includes information about 5,243 residential systems in San Diego Gas & Electric's (SDG&E) service territory installed between January 2007 and December 2010. San Diego is a national leader in the installation of small-scale solar-electric systems, with over 12,000 systems in the region installed as of January 2012, or around 14% of the total number installed in California. The author performed detailed characterization of a significant subset of the solar installations in the San Diego region. Assembled data included technical and economic characteristics of the systems themselves; the solar companies that sold and installed them; individual customer electric utility billing data; metered PV production data for a subgroup of these solar systems; and data about the properties where the systems are located. Primarily, the author was able to conduct an electricity consumption analysis at the individual household level for 2,410 PV systems installed in SDG&E service territory between January 2007 and December 2010. This analysis was designed to detect changes in electricity consumption from the pre-solar to the post-installation period. To

  8. Feasibility study of solar energy in residential electricity generation

    NASA Astrophysics Data System (ADS)

    Solanki, Divyangsinh G.

    With the increasing demand for energy and the concerns about the global environment, along with the steady progress in the field of renewable energy technologies, new opportunities and possibilities are opening up for an efficient utilization of renewable energy sources. Solar energy is undoubtedly the most clean, inexhaustible and abundant source of renewable energy. Photovoltaic (PV) technology is one of the most efficient mean to utilize solar power. The focus of this study was to establish economics of a residential photovoltaic system for a typical home in south Texas. The PV system serves the needs of a typical mid-size home inhibited by a typical family. Assumptions are made for the typical daily energy consumption, and the necessary equipments like solar arrays, batteries, inverter, etc. are sized and evaluated optimally so as to reduce the life cycle cost (LCC) of the system. Calculations are done taking into consideration the economic parameters concerned with the system.

  9. Performance and economics of residential solar space heating

    NASA Astrophysics Data System (ADS)

    Zehr, F. J.; Vineyard, T. A.; Barnes, R. W.; Oneal, D. L.

    1982-11-01

    The performance and economics of residential solar space heating were studied for various locations in the contiguous United States. Common types of active and passive solar heating systems were analyzed with respect to an average-size, single-family house designed to meet or exceed the thermal requirements of the Department of Housing and Urban Development Minimum Property Standards (HUD-MPS). The solar systems were evaluated in seventeen cities to provide a broad range of climatic conditions. Active systems evaluated consist of air and liquid flat plate collectors with single- and double-glazing: passive systems include Trombe wall, water wall, direct gain, and sunspace systems. The active system solar heating performance was computed using the University of Wisconsin's F-CHART computer program. The Los Alamos Scientific Laboratory's Solar Load Ratio (SLR) method was employed to compute solar heating performance for the passive systems. Heating costs were computed with gas, oil, and electricity as backups and as conventional heating system fuels.

  10. Solar access of residential rooftops in four California cities

    SciTech Connect

    Levinson, Ronnen; Akbari, Hashem; Pomerantz, Melvin

    2010-05-14

    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.

  11. Solar Heating and Cooling of Residential Buildings: Sizing, Installation and Operation of Systems.

    ERIC Educational Resources Information Center

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    This training course and a companion course titled "Design of Systems for Solar Heating and Cooling of Residential Buildings," are designed to train home designers and builders in the fundamentals of solar hydronic and air systems for space heating and cooling and domestic hot water heating for residential buildings. Each course, organized in 22…

  12. Development of a solar powered residential air conditioner (General optimization)

    NASA Technical Reports Server (NTRS)

    Lowen, D. J.

    1976-01-01

    A commercially available 3-ton residential Lithium Bromide (LiBr) absorption air conditioner was modified for use with lower temperature solar heated water. The modification included removal of components such as the generator, concentration control chamber, liquid trap, and separator; and the addition of a Chrysler designed generator, an off-the-shelf LiBr-solution pump. The design goal of the modified unit was to operate with water as the heat-transfer fluid at a target temperature of 85 C (185 F), 29.4 C (85 F) cooling water inlet, producing 10.5 kW (3 tons) of cooling. Tests were performed on the system before and after modification to provide comparative data. At elevated temperatures (96 C, 205 F), the test results show that Lithium Bromide was carried into the condenser due to the extremely violent boiling and degraded the evaporator performance.

  13. Preface: Advances in solar physics

    NASA Astrophysics Data System (ADS)

    Georgoulis, Manolis K.; Nakariakov, Valery M.

    2015-12-01

    The idea for this special issue of Advances in Space Research (ASR) was formulated during the 14th European Solar Physics Meeting (ESPM-14) that took place in Dublin, Ireland in September 2014. Since ASR does not publish conference proceedings, it was decided to extend a general call to the international solar-physics community for manuscripts pertinent to the following thematic areas: New and upcoming heliospheric observational and data assimilation facilities.

  14. Advanced photovoltaic solar array development

    NASA Technical Reports Server (NTRS)

    Kurland, Richard M.; Stella, Paul

    1989-01-01

    Phase 2 of the Advanced Photovoltaic Solar Array (APSA) program, started in mid-1987, is currently in progress to fabricate prototype wing hardware that will lead to wing integration and testing in 1989. The design configuration and key details are reviewed. A status of prototype hardware fabricated to date is provided. Results from key component-level tests are discussed. Revised estimates of array-level performance as a function of solar cell device technology for geosynchronous missions are given.

  15. Advanced Solar Receivers

    NASA Technical Reports Server (NTRS)

    Owen, W. A.

    1984-01-01

    Low thermal efficiencies in solar receivers are discussed in terms of system design. It is recommended that careful attention be given to the overall thermal systems design, especially to conductive losses about the window and areas of relatively thin insulation. If the cavity design is carefully managed to insure a small, minimally reradiating aperture, the goal of a very high efficiency cavity receiver is a realistic one.

  16. Incentive Pass-through for Residential Solar Systems in California

    SciTech Connect

    Dong, C. G.; Wiser, Ryan; Rai, Varun

    2014-10-01

    The deployment of solar photovoltaic (PV) systems has grown rapidly over the last decade, partly because of various government incentives. In the United States, among the largest and longest-running incentives have been those established in California. Building on past research, this report addresses the still-unanswered question: to what degree have the direct PV incentives in California been passed through from installers to consumers? This report helps address this question by carefully examining the residential PV market in California (excluding a certain class of third-party-owned PV systems) and applying both a structural-modeling approach and a reduced-form regression analysis to estimate the incentive pass-through rate. The results suggest an average pass-through rate of direct incentives of nearly 100%, though with regional differences among California counties. While these results could have multiple explanations, they suggest a relatively competitive market and well-functioning subsidy program. Further analysis is required to determine whether similar results broadly apply to other states, to other customer segments, to all third-party-owned PV systems, or to all forms of financial incentives for solar (considering not only direct state subsidies, but also utility electric bill savings and federal tax incentives).

  17. Solar heating and cooling of residential buildings: sizing, installation and operation of systems. 1980 edition

    SciTech Connect

    1980-09-01

    This manual was prepared as a text for a training course on solar heating and cooling of residential buildings. The course and text are directed toward sizing, installation, operation, and maintenance of solar systems for space heating and hot water supply, and solar cooling is treated only briefly. (MHR)

  18. Solarize Guidebook: A Community Guide to Collective Purchasing of Residential PV Systems

    SciTech Connect

    Irvine, L.; Sawyer, A.; Grove, J.

    2011-02-01

    This handbook is intended as a road map for project planners and solar advocates who want to convert interest into action, to break through market barriers and permanently transform the market for residential solar installations in their communities. It describes the key elements of the Solarize campaigns in Portland, and offers several program refinements from projects beyond Portland. The handbook provides lessons, considerations, and step-by-step plans for project organizers to replicate the success of Solarize Portland.

  19. Solarize Guidebook: A Community Guide to Collective Purchasing of Residential PV Systems (Book)

    SciTech Connect

    Not Available

    2012-05-01

    This guidebook is intended as a road map for project planners and solar advocates who want to convert 'interest' into 'action,' to break through market barriers and permanently transform the market for residential solar installations in their communities. It describes the key elements of the Solarize campaigns in Portland, and offers several program refinements from projects beyond Portland. The guidebook provides lessons, considerations, and step-by-step plans for project organizers to replicate the success of Solarize Portland.

  20. Site Planning for Solar Access: A Guidebook for Residential Developers and Site Planners.

    ERIC Educational Resources Information Center

    Erley, Duncan; Jaffe, Martin

    This manual is intended to guide developers, site planners, and builders in designing residential developments so that access to sunlight is maintained for planned or potential solar collectors. Almost any housing development can be designed to facilitate the use of solar energy. Differences are not in costs but in planning. Described in this…

  1. Reconciling Consumer and Utility Objectives in the Residential Solar PV Market

    NASA Astrophysics Data System (ADS)

    Arnold, Michael R.

    Today's energy market is facing large-scale changes that will affect all market players. Near the top of that list is the rapid deployment of residential solar photovoltaic (PV) systems. Yet that growing trend will be influenced multiple competing interests between various stakeholders, namely the utility, consumers and technology provides. This study provides a series of analyses---utility-side, consumer-side, and combined analyses---to understand and evaluate the effect of increases in residential solar PV market penetration. Three urban regions have been selected as study locations---Chicago, Phoenix, Seattle---with simulated load data and solar insolation data at each locality. Various time-of-use pricing schedules are investigated, and the effect of net metering is evaluated to determine the optimal capacity of solar PV and battery storage in a typical residential home. The net residential load profile is scaled to assess system-wide technical and economic figures of merit for the utility with an emphasis on intraday load profiles, ramp rates and electricity sales with increasing solar PV penetration. The combined analysis evaluates the least-cost solar PV system for the consumer and models the associated system-wide effects on the electric grid. Utility revenue was found to drop by 1.2% for every percent PV penetration increase, net metering on a monthly or annual basis improved the cost-effectiveness of solar PV but not battery storage, the removal of net metering policy and usage of an improved the cost-effectiveness of battery storage and increases in solar PV penetration reduced the system load factor. As expected, Phoenix had the most favorable economic scenario for residential solar PV, primarily due to high solar insolation. The study location---solar insolation and load profile---was also found to affect the time of year at which the largest net negative system load was realized.

  2. Advances in Solar Power Forecasting

    NASA Astrophysics Data System (ADS)

    Haupt, S. E.; Kosovic, B.; Drobot, S.

    2014-12-01

    The National Center for Atmospheric Research and partners are building a blended SunCast Solar Power Forecasting system. This system includes several short-range nowcasting models and improves upon longer range numerical weather prediction (NWP) models as part of the "Public-Private-Academic Partnership to Advance Solar Power Forecasting." The nowcasting models being built include statistical learning models that include cloud regime prediction, multiple sky imager-based advection models, satellite image-based advection models, and rapid update NWP models with cloud assimilation. The team has also integrated new modules into the Weather Research and Forecasting Model (WRF) to better predict clouds, aerosols, and irradiance. The modules include a new shallow convection scheme; upgraded physics parameterizations of clouds; new radiative transfer modules that specify GHI, DNI, and DIF prediction; better satellite assimilation methods; and new aerosol estimation methods. These new physical models are incorporated into WRF-Solar, which is then integrated with publically available NWP models via the Dynamic Integrated Forecast (DICast) system as well as the Nowcast Blender to provide seamless forecasts at partner utility and balancing authority commercial solar farms. The improvements will be described and results to date discussed.

  3. Are policy incentives for solar power effective? Evidence from residential installations in the Northeast

    SciTech Connect

    Crago, Christine Lasco; Chernyakhovskiy, Ilya

    2017-01-01

    State incentives for solar power have grown significantly in the past several years. This paper examines the effectiveness of policy incentives to increase residential solar photovoltaic (PV) capacity. We use county-level panel data and control for demographic characteristics, solar resources, and pro-environmental preferences. Results show that among financial incentives, rebates have the most impact with an additional $1 per watt rebate increasing annual PV capacity additions by close to 50%. Factors that affect financial returns to solar PV such as electricity price and solar insolation are also found to be significant. Results also point to a significant positive relationship between hybrid vehicle sales and residential PV capacity growth, indicating the importance of pro-environmental preferences as a predictor of solar PV demand. Back of the envelope calculations suggest that the cost of carbon mitigation through rebates is around $184 per ton of CO2.

  4. Block 4 solar cell module design and test specification for residential applications

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Near-term design, qualification and acceptance requirements are provided for terrestrial solar cell modules suitable for incorporation in photovoltaic power sources (2 kW to 10 kW) applied to single family residential installations. Requirement levels and recommended design limits for selected performance criteria are specified for modules intended principally for rooftop installations. Modules satisfying the requirements of this specification fall into one of two categories, residential panel or residential shingle, both meeting general performance requirements plus additional category peculiar constraints.

  5. Residential Solar Photovoltaics: Comparison of Financing Benefits, Innovations, and Options

    SciTech Connect

    Speer, B.

    2012-10-01

    This report examines relatively new, innovative financing methods for residential photovoltaics (PV) and compares them to traditional self-financing. It provides policymakers with an overview of the residential PV financing mechanisms, describes relative advantages and challenges, and analyzes differences between them where data is available. Because these innovative financing mechanisms have only been implemented in a few locations, this report can inform their wider adoption.

  6. Advances in Solar Heating and Cooling Systems

    ERIC Educational Resources Information Center

    Ward, Dan S.

    1976-01-01

    Reports on technological advancements in the fields of solar collectors, thermal storage systems, and solar heating and cooling systems. Diagrams aid in the understanding of the thermodynamics of the systems. (CP)

  7. Solar Concentrator Advanced Development Program

    NASA Technical Reports Server (NTRS)

    Knasel, Don; Ehresman, Derik

    1989-01-01

    The Solar Concentrator Advanced Development Project has successfully designed, fabricated, and tested a full scale prototypical solar dynamic concentrator for space station applications. A Truss Hexagonal Panel reflector was selected as a viable solar concentrator concept to be used for space station applications. This concentrator utilizes a modular design approach and is flexible in attainable flux profiles and assembly techniques. The detailed design of the concentrator, which included structural, thermal and optical analysis, identified the feasibility of the design and specific technologies that were required to fabricate it. The needed surface accuracy of the reflectors surface was found to be very tight, within 5 mrad RMS slope error, and results in very close tolerances for fabrication. To meet the design requirements, a modular structure composed of hexagonal panels was used. The panels, made up of graphite epoxy box beams provided the strength, stiffness and dimensional stability needed. All initial project requirements were met or exceeded by hardware demonstration. Initial testing of structural repeatability of a seven panel portion of the concentrator was followed by assembly and testing of the full nineteen panel structure. The testing, which consisted of theodolite and optical measurements over an assembly-disassembly-reassembly cycle, demonstrated that the concentrator maintained the as-built contour and optical characteristics. The facet development effort within the project, which included developing the vapor deposited reflective facet, produced a viable design with demonstrated optical characteristics that are within the project goals.

  8. Effect of residential solar and storage on centralized electricity supply systems

    NASA Astrophysics Data System (ADS)

    Agnew, Scott; Dargusch, Paul

    2015-04-01

    Residential solar photovoltaic systems combined with affordable battery storage are becoming increasingly likely to drive a consumer-led, low-emission evolution of modern electricity supply systems. In the past decade, a multi-billion-dollar boom in solar photovoltaic development across the globe has disrupted the way in which centralized electricity systems operate. At the same time, solar photovoltaic power has begun to make a material contribution to reduction targets for greenhouse gas emissions. Viable electricity storage solutions are now on the cusp of a rapidly declining price trajectory. When coupled with solar photovoltaic systems, battery storage could become one of the most disruptive influences to impact the electricity sector in decades, yet governments and the broader power sector are poorly prepared. In this Perspective, we examine emerging trends and proffer a systems framework to analyse the disruptive influence of residential solar photovoltaic and storage systems on existing centralized electricity supply systems.

  9. Advancing Concentrating Solar Power Research (Fact Sheet)

    SciTech Connect

    Not Available

    2014-02-01

    Researchers at the National Renewable Energy Laboratory (NREL) provide scientific, engineering, and analytical expertise to help advance innovation in concentrating solar power (CSP). This fact sheet summarizes how NREL is advancing CSP research.

  10. Evaluation of advanced technologies for residential appliances and residential and commercial lighting

    SciTech Connect

    Turiel, I.; Atkinson, B.; Boghosian, S.; Chan, P.; Jennings, J.; Lutz, J.; McMahon, J.; Rosenquist, G.

    1995-01-01

    Section 127 of the Energy Policy Act requires that the Department of Energy (DOE) prepare a report to Congress on the potential for the development and commercialization of appliances that substantially exceed the present federal or state efficiency standards. Candidate high-efficiency appliances must meet several criteria including: the potential exists for substantial improvement (beyond the minimum established in law) of the appliance`s energy efficiency; electric, water, or gas utilities are prepared to support and promote the commercialization of such appliances; manufacturers are unlikely to undertake development and commercialization of such appliances on their own, or development and production would be substantially accelerated by support to manufacturers. This report describes options to improve the efficiency of residential appliances, including water heaters, clothes washers and dryers, refrigerator/freezers, dishwashers, space heating and cooling devices, as well as residential and commercial lighting products. Data from this report (particularly Appendix 1)were used to prepare the report to Congress mentioned previously. For the residential sector, national energy savings are calculated using the LBL Residential Energy Model. This model projects the number of households and appliance saturations over time. First, end-use consumption is calculated for a base case where models that only meet the standard replace existing models as these reach the end of their lifetime. Second, models with efficiencies equal to the technology under consideration replace existing models that reach the end of their lifetime. For the commercial sector, the COMMEND model was utilized to project national energy savings from new technologies. In this report, energy savings are shown for the period 1988 to 2015.

  11. Analysis of Bright Harvest Remote Analysis for Residential Solar Installations

    SciTech Connect

    Nangle, John; Simon, Joseph

    2015-06-17

    Bright Harvest provides remote shading analysis and design products for residential PV system installers. The National Renewable Energy Laboratory (NREL) through the NREL Commercialization Assistance Program, completed comparative assessments between on-site measurements and remotely calculated values to validate the accuracy of Bright Harvest’s remote shading and power generation.

  12. Residential solar hot water system--Tempe, Arizona

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Domestic hot water for single story home is heated by two 4 by 8 foot solar collectors. Solar energy saved 5.54 million Btu in six month period; savings with increased water consumption would be significantly higher.

  13. 78 FR 19099 - Residential, Business, and Wind and Solar Resource Leases on Indian Land

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-29

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs 25 CFR Part 162 RIN 1076-AE73 Residential, Business, and Wind and Solar Resource... lease'' and clarifies two provisions for wind energy evaluation leases (WEELs). DATES: This...

  14. 78 FR 27859 - Residential, Business, and Wind and Solar Resource Leases on Indian Land

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF THE INTERIOR Bureau of Indian Affairs 25 CFR Part 162 RIN 1076-AE73 Residential, Business, and Wind and Solar Resource Leases on Indian Land AGENCY: Bureau of Indian Affairs, Interior. ACTION: Final rule;...

  15. Solar Energy: Non-Residential Applications and Future Technology: Student Material. First Edition.

    ERIC Educational Resources Information Center

    Takacs, Robert; Orsak, Charles G., Jr.

    Student materials are presented for the course, Non-Residential Applications and Future Technology, one of seven core courses in Navarro College's two-year associate degree program for solar technicians. First, introductory material discusses the form and objectives of the course and ways of using the student materials. Next, readings, worksheets,…

  16. The Consortium of Advanced Residential Buildings (CARB) - A Building America Energy Efficient Housing Partnership

    SciTech Connect

    Robb Aldrich; Lois Arena; Dianne Griffiths; Srikanth Puttagunta; David Springer

    2010-12-31

    This final report summarizes the work conducted by the Consortium of Advanced Residential Buildings (CARB) (http://www.carb-swa.com/), one of the 'Building America Energy Efficient Housing Partnership' Industry Teams, for the period January 1, 2008 to December 31, 2010. The Building America Program (BAP) is part of the Department of Energy (DOE), Energy Efficiency and Renewable Energy, Building Technologies Program (BTP). The long term goal of the BAP is to develop cost effective, production ready systems in five major climate zones that will result in zero energy homes (ZEH) that produce as much energy as they use on an annual basis by 2020. CARB is led by Steven Winter Associates, Inc. with Davis Energy Group, Inc. (DEG), MaGrann Associates, and Johnson Research, LLC as team members. In partnership with our numerous builders and industry partners, work was performed in three primary areas - advanced systems research, prototype home development, and technical support for communities of high performance homes. Our advanced systems research work focuses on developing a better understanding of the installed performance of advanced technology systems when integrated in a whole-house scenario. Technology systems researched included: - High-R Wall Assemblies - Non-Ducted Air-Source Heat Pumps - Low-Load HVAC Systems - Solar Thermal Water Heating - Ventilation Systems - Cold-Climate Ground and Air Source Heat Pumps - Hot/Dry Climate Air-to-Water Heat Pump - Condensing Boilers - Evaporative condensers - Water Heating CARB continued to support several prototype home projects in the design and specification phase. These projects are located in all five program climate regions and most are targeting greater than 50% source energy savings over the Building America Benchmark home. CARB provided technical support and developed builder project case studies to be included in near-term Joule Milestone reports for the following community scale projects: - SBER Overlook at Clipper

  17. Recent Advances in Solar Cell Technology

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila G.; Piszczor, Michael F., Jr.

    1996-01-01

    The advances in solar cell efficiency, radiation tolerance, and cost over the last decade are reviewed. Potential performance of thin-film solar cells in space are discussed, and the cost and the historical trends in production capability of the photovoltaics industry are considered with respect to the requirements of space power systems. Concentrator cells with conversion efficiency over 30%, and nonconcentrating solar cells with efficiency over 25% are now available, and advanced radiation-tolerant cells and lightweight, thin-film arrays are both being developed. Nonsolar applications of solar cells, including thermophotovoltaics, alpha- and betavoltaics, and laser power receivers, are also discussed.

  18. Design, fabrication, testing, and delivery of a solar energy collector system for residential heating and cooling

    NASA Technical Reports Server (NTRS)

    Holland, T. H.; Borzoni, J. T.

    1976-01-01

    A low cost flat plate solar energy collector was designed for the heating and cooling of residential buildings. The system meets specified performance requirements, at the desired system operating levels, for a useful life of 15 to 20 years, at minimum cost and uses state-of-the-art materials and technology. The rationale for the design method was based on identifying possible material candidates for various collector components and then selecting the components which best meet the solar collector design requirements. The criteria used to eliminate certain materials were: performance and durability test results, cost analysis, and prior solar collector fabrication experience.

  19. The development of a solar-powered residential heating and cooling system

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Efforts to demonstrate the engineering feasibility of utilizing solar power for residential heating and cooling are described. These efforts were concentrated on the analysis, design, and test of a full-scale demonstration system which is currently under construction at the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville, Alabama. The basic solar heating and cooling system under development utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating and water heating, and an absorption cycle air conditioner for space cooling.

  20. Residential heating costs: a comparison of geothermal, solar and conventional resources

    SciTech Connect

    Bloomster, C.H.; Garrett-Price, B.A.; Fassbender, L.L.

    1980-08-01

    The costs of residential heating throughout the United States using conventional, solar, and geothermal energy were determined under current and projected conditions. These costs are very sensitive to location - being dependent on the local prices of conventional energy supplies, local solar insolation, cimate, and the proximity and temperature of potential geothermal resources. The sharp price increases in imported fuels during 1979 and the planned decontrol of domestic oil and natural gas prices have set the stage for geothermal and solar market penetration in the 1980's.

  1. Advanced Rainbow Solar Photovoltaic Arrays

    NASA Technical Reports Server (NTRS)

    Mardesich, Nick; Shields, Virgil

    2003-01-01

    Photovoltaic arrays of the rainbow type, equipped with light-concentrator and spectral-beam-splitter optics, have been investigated in a continuing effort to develop lightweight, high-efficiency solar electric power sources. This investigation has contributed to a revival of the concept of the rainbow photovoltaic array, which originated in the 1950s but proved unrealistic at that time because the selection of solar photovoltaic cells was too limited. Advances in the art of photovoltaic cells since that time have rendered the concept more realistic, thereby prompting the present development effort. A rainbow photovoltaic array comprises side-by-side strings of series-connected photovoltaic cells. The cells in each string have the same bandgap, which differs from the bandgaps of the other strings. Hence, each string operates most efficiently in a unique wavelength band determined by its bandgap. To obtain maximum energy-conversion efficiency and to minimize the size and weight of the array for a given sunlight input aperture, the sunlight incident on the aperture is concentrated, then spectrally dispersed onto the photovoltaic array plane, whereon each string of cells is positioned to intercept the light in its wavelength band of most efficient operation. The number of cells in each string is chosen so that the output potentials of all the strings are the same; this makes it possible to connect the strings together in parallel to maximize the output current of the array. According to the original rainbow photovoltaic concept, the concentrated sunlight was to be split into multiple beams by use of an array of dichroic filters designed so that each beam would contain light in one of the desired wavelength bands. The concept has since been modified to provide for dispersion of the spectrum by use of adjacent prisms. A proposal for an advanced version calls for a unitary concentrator/ spectral-beam-splitter optic in the form of a parabolic curved Fresnel-like prism

  2. Residential solar-heating system uses pyramidal optics

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Report describes reflective panels which optimize annual solar energy collection in attic installation. Subunits include collection, storage, distribution, and 4-mode control systems. Pyramid optical system heats single-family and multi-family dwellings.

  3. Prototype residential solar-energy system-installation package

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Installation guidelines for architects and engineers discussing solar-heating system built in Togus, Maine are presented. Includes brief, functional description of system and summary of operation. Drawings complement text.

  4. Solar residential heating and cooling system development test program

    NASA Technical Reports Server (NTRS)

    Humphries, W. R.; Melton, D. E.

    1974-01-01

    A solar heating and cooling system is described, which was installed in a simulated home at Marshall Space Flight Center. Performance data are provided for the checkout and initial operational phase for key subsystems and for the total system. Valuable information was obtained with regard to operation of a solar cooling system during the first summer of operation. Areas where improvements and modifications are required to optimize such a system are discussed.

  5. Advancements in Solar Neutrino Physics

    NASA Astrophysics Data System (ADS)

    Miramonti, Lino; Antonelli, Vito

    2013-03-01

    We review the results of solar neutrino physics, with particular attention to the data obtained and the analyses performed in the last decades, which were determinant to solve the solar neutrino problem (SNP), proving that neutrinos are massive and oscillating particles and contributing to refine the solar models. We also discuss the perspectives of the presently running experiments in this sector and of the ones planned for the near future and the impact they can have on elementary particle physics and astrophysics.

  6. Results of ASHRAE 95 thermal testing of 32 residential solar water heating systems

    NASA Astrophysics Data System (ADS)

    Chinery, G. T.; Wessling, F. C., Jr.

    The results of ASHRAE 95 thermal testing for 32 residential solar water heating systems that were submitted for TVA's Nashville 10,000 Residential Solar Water Heating Project are presented with system descriptions and a review of the test methodology. The tested systems included drain back, drain down, closed loop and air designs and utilized water, glycol/water mixtures, silicone oil and air heat transfer fluids. Systems tested included one and two tank designs with individual tank sizes ranging from 0.15 cu m (40 gal) to 0.45 cu m (120 gal). Collectors comprised of selective and nonselective surfaces had array areas ranging from 3.40 sq m (36.6 sq ft) to 9.65 sq m (103.8 sq ft). The system energy multipliers ranged from 0.96 to 3.6 and calculated fractional energy savings ranged from 17 percent to 78 percent. Experimental validation of the test method is underway.

  7. Residential solar-heating system-design package

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Design package for modular solar heating system includes performance specifications, design data, installation guidelines, and other information that should be valuable to those interested in system (or similar systems) for projected installation. When installed in insulated "energy saver" home, system can supply large percentage of total energy needs of building.

  8. The development of a solar residential heating and cooling system

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The MSFC solar heating and cooling facility was assembled to demonstrate the engineering feasibility of utilizing solar energy for heating and cooling buildings, to provide an engineering evaluation of the total system and the key subsystems, and to investigate areas of possible improvement in design and efficiency. The basic solar heating and cooling system utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating, and an absorption cycle air conditioner for space cooling. A complete description of all systems is given. Development activities for this test system included assembly, checkout, operation, modification, and data analysis, all of which are discussed. Selected data analyses for the first 15 weeks of testing are included, findings associated with energy storage and the energy storage system are outlined, and conclusions resulting from test findings are provided. An evaluation of the data for summer operation indicates that the current system is capable of supplying an average of 50 percent of the thermal energy required to drive the air conditioner. Preliminary evaluation of data collected for operation in the heating mode during the winter indicates that nearly 100 percent of the thermal energy required for heating can be supplied by the system.

  9. Selecting Solar. Insights into Residential Photovoltaic (PV) Quote Variation

    SciTech Connect

    Davidson, Carolyn; Margolis, Robert

    2015-10-01

    This analysis leverages available data from EnergySage, an online solar marketplace, to offer the first data-driven characterization of quote variation faced by prospective PV customers, lending early insight into the decisions customers face once they have initial buy-in.

  10. Solar Heating and Cooling of Residential Buildings: Design of Systems.

    ERIC Educational Resources Information Center

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    This is the second of two training courses designed to develop the capability of practitioners in the home building industry to design solar heating and cooling systems. The course is organized in 23 modules to separate selected topics and to facilitate learning. Although a compact schedule of one week is shown, a variety of formats can be…

  11. Development of a solar-powered residential air conditioner

    NASA Technical Reports Server (NTRS)

    1975-01-01

    An extensive review of the literature was conducted which was concerned with the characterization of systems and equipment that could be applicable to the development of solar-powered air conditioners based on the Rankine cycle approach, and the establishment of baseline data defining the performance, physical characteristics, and cost of systems using the LiBr/H2O absorption cycle.

  12. Evaluation of residential and commercial solar/gas heating and cooling technologies, volume 2

    NASA Astrophysics Data System (ADS)

    Hirshberg, A. S.; Haas, S. A.; Jacobsen, A. S.

    1980-12-01

    The economics of the most cost-effective solar/gas hybrid systems against a range of advanced gas-fired space conditioning equipment, including both conventional gas furnaces and pulse combustion gas furnaces were analyzed. In addition, the economic comparison considered improvements in performance and cost reduction for both solar/gas systems and advanced gas-fired equipment.

  13. Estimating solar access of typical residential rooftops: A case study in San Jose, CA

    SciTech Connect

    Levinson, Ronnen M.; Gupta, Smita; Akbari, Hashem; Pomerantz, Melvin

    2008-03-03

    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 rooftop shading in a residential neighborhood of San Jose, CA, one of four regions analyzed in a wider study of the solar access of California homes.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 4 km2 residential neighborhood. Hourly shading of roofing planes (the flat elements of roofs) was computed geometrically from the digital elevation model. Parcel boundaries were used to determine the extent to which roofing planes were shaded by trees and buildings in neighboring parcels.In the year in which surface heights were measured (2005), shadows from all sources ("total shading") reduced the insolation received by S-, SW-, and W-facing residential roofing planes in the study area by 13 - 16percent. Shadows cast by trees and buildings in neighboring parcels reduced insolation by no more than 2percent. After 30 years of simulated maximal tree growth, annual total shading increased to 19 - 22percent, and annual extraparcel shading increased to 3 - 4percent.

  14. Solar photovoltaic/thermal residential experiment, phase 2

    NASA Astrophysics Data System (ADS)

    Kugle, S. T.; Leith, J. R.; Svane, M. S.

    1981-08-01

    Performance and operation of photovoltaic and thermal solar heating and cooling systems were evaluated in order to assess the feasibility of hybrid photovoltaic/thermal collectors. Experiments were carried out at an instrumented single-family dwelling/research facility at the University of Texas at Arlington. The cooling load was the dominant comfort consideration, since the climate at the research site (in north central Texas) is generally regarded as humid subtropical with hot summers. Several solar-assisted heating and cooling configurations were considered for a basic system comprised of the photovoltaic and thermal collectors, a thermal storage tank, and a two-speed heat pump. The photovoltaic array, with an area of 109 sq. m was part of a utility-interactive ('line-stuffing') power system. Average solar-to-dc conversion efficiency of the array was 4.7%. Efficiency of the thermal collectors, with an area of 48.4 sq. m, was 5 to 20% and was dependent upon the difference between the glycol-water collector loop and thermal storage tank temperatures. Design objectives and operational strategies for hybrid photovoltaic/thermal collector systems were developed.

  15. Advanced Controls for Residential Whole-House Ventilation Systems

    SciTech Connect

    Turner, William; Walker, Iain; Sherman, Max

    2014-08-01

    Whole-house ventilation systems are becoming commonplace in new construction, remodeling/renovation, and weatherization projects, driven by combinations of specific requirements for indoor air quality (IAQ), health and compliance with standards, such as ASHRAE 62.2. Ventilation systems incur an energy penalty on the home via fan power used to drive the airflow, and the additional space-conditioning load associated with heating or cooling the ventilation air. Finding a balance between IAQ and energy use is important if homes are to be adequately ventilated while not increasing the energy burden. This study used computer simulations to examine RIVEC the Residential Integrated Ventilation Controller - a prototype ventilation controller that aims to deliver whole-house ventilation rates that comply with ventilation standards, for the minimum use of energy. Four different whole-house ventilation systems were simulated, both with and without RIVEC, so that the energy and IAQ results could be compared. Simulations were conducted for 13 US climate zones, three house designs, and three envelope leakage values. The results showed that the RIVEC controller could typically return ventilation energy savings greater than 40percent without compromising long-term chronic or short-term acute exposures to relevant indoor contaminants. Critical and average peak power loads were also reduced as a consequence of using RIVEC.

  16. Solar heating and cooling of residential buildings: design of systems, 1980 edition

    SciTech Connect

    1980-09-01

    This manual was prepared primarily for use in conducting a practical training course on the design of solar heating and cooling systems for residential and small office buildings, but may also be useful as a general reference text. The content level is appropriate for persons with different and varied backgrounds, although it is assumed that readers possess a basic understanding of heating, ventilating, and air-conditioning systems of conventional (non-solar) types. This edition is a revision of the manual with the same title, first printed and distributed by the US Government Printing Office in October 1977. The manual has been reorganized, new material has been added, and outdated information has been deleted. Only active solar systems are described. Liquid and air-heating solar systems for combined space and service water heating or service water heating are included. Furthermore, only systems with proven experience are discussed to any extent.

  17. Selecting Solar: Insights into Residential Photovoltaic (PV) Quote Variation

    SciTech Connect

    Davidson, Carolyn; Margolis, Robert

    2015-10-01

    Before investing in a system, a prospective PV customer must not only have initial concept 'buy in,' but also be able to evaluate the tradeoffs associated with different system parameters. Prospective customers might need to evaluate disparate costs for each system attribute by comparing multiple bids. The difficulty of making such an evaluation with limited information can create a cognitive barrier to proceeding with the investment. This analysis leverages recently available data from EnergySage, an online solar marketplace, to offer the first data-driven characterization of quote variation faced by prospective PV customers, lending early insight into the decisions customers face once they have initial buy-in.

  18. Advances in Perovskite Solar Cells

    PubMed Central

    Zuo, Chuantian; Bolink, Henk J.; Han, Hongwei; Huang, Jinsong

    2016-01-01

    Organolead halide perovskite materials possess a combination of remarkable optoelectronic properties, such as steep optical absorption edge and high absorption coefficients, long charge carrier diffusion lengths and lifetimes. Taken together with the ability for low temperature preparation, also from solution, perovskite‐based devices, especially photovoltaic (PV) cells have been studied intensively, with remarkable progress in performance, over the past few years. The combination of high efficiency, low cost and additional (non‐PV) applications provides great potential for commercialization. Performance and applications of perovskite solar cells often correlate with their device structures. Many innovative device structures were developed, aiming at large‐scale fabrication, reducing fabrication cost, enhancing the power conversion efficiency and thus broadening potential future applications. This review summarizes typical structures of perovskite solar cells and comments on novel device structures. The applications of perovskite solar cells are discussed. PMID:27812475

  19. Advances in Perovskite Solar Cells.

    PubMed

    Zuo, Chuantian; Bolink, Henk J; Han, Hongwei; Huang, Jinsong; Cahen, David; Ding, Liming

    2016-07-01

    Organolead halide perovskite materials possess a combination of remarkable optoelectronic properties, such as steep optical absorption edge and high absorption coefficients, long charge carrier diffusion lengths and lifetimes. Taken together with the ability for low temperature preparation, also from solution, perovskite-based devices, especially photovoltaic (PV) cells have been studied intensively, with remarkable progress in performance, over the past few years. The combination of high efficiency, low cost and additional (non-PV) applications provides great potential for commercialization. Performance and applications of perovskite solar cells often correlate with their device structures. Many innovative device structures were developed, aiming at large-scale fabrication, reducing fabrication cost, enhancing the power conversion efficiency and thus broadening potential future applications. This review summarizes typical structures of perovskite solar cells and comments on novel device structures. The applications of perovskite solar cells are discussed.

  20. Solar concentrator advanced development project

    NASA Technical Reports Server (NTRS)

    Corrigan, Robert D.; Ehresman, Derik T.

    1987-01-01

    A solar dynamic concentrator design developed for use with a solar-thermodynamic power generation module intended for the Space Station is considered. The truss hexagonal panel reflector uses a modular design approach and is flexible in attainable flux profiles and assembly techniques. Preliminary structural, thermal, and optical analysis results are discussed. Accuracy of the surface reflectors should be within 5 mrad rms slope error, resulting in the need for close fabrication tolerances. Significant fabrication issues to be addressed include the facet reflective and protective coating processes and the surface specularity requirements.

  1. Survey of failure modes from 122 residential solar water heaters

    SciTech Connect

    Not Available

    1984-10-01

    This report describes the results of a survey on the operation of active solar heating and cooling systems and their components. Questionnaires were sent to homeowners and installers, covering 122 systems. Results were categorized according to problem severity, location, system type, length of system operation, and time of the year. Approximately 47% of the systems had at least one reliability problem over a two-year period. Flat-plate collector and storage systems were highly reliable. Improper operation of these components was attributed to installation problems. Drainback designs also had the greatest reliability; draindown systems were the least reliable, largely because of the failure of draindown valves. Differential controllers caused the largest number of failures that resulted in a repair cost in excess of $50 to the homeowner.

  2. Advanced solar concentrator: Executive summary

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The preliminary design of a point-focusing solar concentrator, consisting of a steerable space frame structure supporting a paraboloidal mirror glass reflector, is described. A mass production, operation, and maintenance cost assessment is presented. A conceptual evaluation of a modified concentrator design is included. The detailed design of one of the lightweight, structurally efficient reflective elements comprising the paraboloidal reflective surface is given.

  3. Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System

    SciTech Connect

    Agamy, Mohammed

    2015-10-27

    The “Module Embedded Micro-inverter Smart Grid Ready Residential Solar Electric System” program is focused on developing innovative concepts for residential photovoltaic (PV) systems with the following objectives: to create an Innovative micro-inverter topology that reduces the cost from the best in class micro-inverter and provides high efficiency (>96% CEC - California Energy Commission), and 25+ year warranty, as well as reactive power support; integrate micro-inverter and PV module to reduce system price by at least $0.25/W through a) accentuating dual use of the module metal frame as a large area heat spreader reducing operating temperature, and b) eliminating redundant wiring and connectors; and create micro-inverter controller handles smart grid and safety functions to simplify implementation and reduce cost.

  4. Residential Solar PV Systems in the Carolinas: Opportunities and Outcomes.

    PubMed

    Alqahtani, Bandar Jubran; Holt, Kyra Moore; Patiño-Echeverri, Dalia; Pratson, Lincoln

    2016-02-16

    This paper presents a first-order analysis of the feasibility and technical, environmental, and economic effects of large levels of solar photovoltaic (PV) penetration within the services areas of the Duke Energy Carolinas (DEC) and Duke Energy Progress (DEP). A PV production model based on household density and a gridded hourly global horizontal irradiance data set simulates hourly PV power output from roof-top installations, while a unit commitment and real-time economic dispatch (UC-ED) model simulates hourly system operations. We find that the large generating capacity of base-load nuclear power plants (NPPs) without ramping capability in the region limits PV integration levels to 5.3% (6510 MW) of 2015 generation. Enabling ramping capability for NPPs would raise the limit of PV penetration to near 9% of electricity generated. If the planned retirement of coal-fired power plants together with new installations and upgrades of natural gas and nuclear plants materialize in 2025, and if NPPs operate flexibly, then the share of coal-fired electricity will be reduced from 37% to 22%. A 9% penetration of electricity from PV would further reduce the share of coal-fired electricity by 4-6% resulting in a system-wide CO2 emissions rate of 0.33 to 0.40 tons/MWh and associated abatement costs of 225-415 (2015$ per ton).

  5. Advanced Solar Observatory (ASO) accommodations requirements study

    NASA Technical Reports Server (NTRS)

    1989-01-01

    Results of an accommodations analysis for the Advanced Solar Observatory on Space Station Freedom are reported. Concepts for the High Resolution Telescope Cluster, Pinhole/Occulter Facility, and High Energy Cluster were developed which can be accommodated on Space Station Freedom. It is shown that workable accommodations concepts are possible. Areas of emphasis for the next stage of engineering development are identified.

  6. Economic analysis of residential and commercial solar heating and hot water systems

    SciTech Connect

    1980-09-23

    The economic evaluation of residential and commercial solar heating and hot water systems is presented. Commercial systems are further categorized as taxable and non-taxable applications in recognition of the effect of Federal and state tax incentives and disincentives for solar energy systems. The economic evaluation of each system type is performed utilizing two distinct methods of analysis. The economic analyses follow a brief description of each method. The Cash Flow Analyses provide insight into the short and long term effects of a solar investment on the budget of the solar energy system purchaser while the Return-On-Investment Analyses provide an appropriate method of measuring the attractiveness of a solar investment in comparison to alternative long term investments. Utilizing a typical system for each system type and application the Cash Flow and Return-On-Investment Analyses are presented. The sensitivity of the results on the numerous variables in the economic analyses is shown. Maps provide a graphic display of the results of the economic analysis of typical systems using Federal and state tax credits and average state conventional fuel costs for each system type. Conclusions based on the economic analyses performed and a thorough discussion of the present status of the data required for the complete economic evaluation of solar energy systems are summarized. The current availability and limitations of data and requirements for further work in this area are discussed.

  7. Moments of homecoming among people with advanced dementia disease in a residential care facility.

    PubMed

    Norberg, Astrid; Ternestedt, Britt-Marie; Lundman, Berit

    2015-10-26

    This study concerns moments of homecoming among people with advanced dementia disease living in a residential care facility. Our main finding from participant observations with nine residents was that the residents showed moments of homecoming, i.e. they alternated between verbal and/or nonverbal expressions of feeling at home and of not feeling at home. If care providers understand that they can help people with advanced dementia disease experience moments of homecoming, they can focus on aspects of care that can promote these experiences.

  8. The Price-Concentration Relationship in Early Residential Solar Third-Party Markets

    SciTech Connect

    Pless, Jacquelyn; Langheim, Ria; Machak, Christina; Hellow, Henar; Sigrin, Ben

    2017-01-01

    The market for residential solar photovoltaic (PV) systems in the United States has experienced tremendous growth over the past decade, with installed capacity more than doubling between 2014 and 2016 alone (SEIA, 2016). As the residential market continues to grow, it prompts new questions about the nature of competition between solar installers and how this competition, or lack thereof, affects the prices consumers are paying. It is often assumed that more competition leads to lower prices, but this is not universally true. For example, some studies have shown that factors such as brand loyalty could lead to a negative relationship between concentration and price in imperfectly competitive markets (Borenstein, 1985; Holmes, 1989). As such, the relationship between prices and market concentration is an open empirical question since theory could predict either a positive or negative relationship. Determining a relationship between prices and market concentration is challenging for several reasons. Most significantly, prices and market structure are simultaneously determined by each other -- the amount of competition a seller faces influences the price they can command, and prices determine a seller's market share. Previous studies have examined recent PV pricing trends over time and between markets (Davidson et al., 2015a; Davidson and Margolis 2015b; Nemet et al., 2016; Gillingham et al., 2014; Barbose and Darghouth 2015). While these studies of solar PV pricing are able to determine correlations between prices and market factors, they have not satisfactorily proven causation. Thus, to the best of our knowledge, there is little work to date that focuses on identifying the causal relationship between market structure and the prices paid by consumers. We use a unique dataset on third-party owned contract terms for the residential solar PV market in the San Diego Gas and Electricity service territory to better understand this relationship. Surprisingly, we find that

  9. Results of ASHRAE 95 thermal testing of 32 residential solar water heating systems

    NASA Astrophysics Data System (ADS)

    Chinery, G. T.; Wessling, F. C., Jr.

    Thermal testing for 32 residential solar water heating systems that are presented with system descriptions and a review of the test methodology. The tested systems included drain back, drain down, closed loop and air designs and utilized water, glycol/water mixtures, silicone oil and air heat transfer fluids. Systems tested included one and two tank designs. Collectors comprised of selective and nonselective surfaces. The system energy multipliers ranged from 0.96 to 3.6 and calculated fractional energy savings ranged from 17% to 78%.

  10. The characterization and assessment of selected solar thermal energy systems for residential and process heat applications

    NASA Astrophysics Data System (ADS)

    Hyde, J. C.

    1980-09-01

    Results of studies of seven solar thermal energy applications are presented. Five of these are residential applications: space heating--active liquid, space heating--active air, domestic hot water--active, space heating--passive, and space heating and cooling--active liquid. Denver, Colorado, was selected as a representative location for each of the above applications. The remaining two applications produce industrial process heat: a flat plate collector system producing 50 C - 100 C hot water for a commercial laundry in Indianapolis, Indiana; and a concentrating collector system that could produce 100 C - 300 C process heat adequate to the needs of a pulp mill in Madison, Wisconsin.

  11. Advanced reflector materials for solar concentrators

    SciTech Connect

    Jorgensen, G; Williams, T; Wendelin, T

    1994-10-01

    This paper describes the research and development program at the U.S. National Renewable Energy Laboratory (NREL) in advanced reflector materials for solar concentrators. NREL's research thrust is to develop solar reflector materials that maintain high specular reflectance for extended lifetimes under outdoor service conditions and whose cost is significantly lower than existing products. Much of this work has been in collaboration with private-sector companies that have extensive expertise in vacuum-coating and polymer-film technologies. Significant progress and other promising developments will be discussed. These are expected to lead to additional improvements needed to commercialize solar thermal concentration systems and make them economically attractive to the solar manufacturing industry. To explicitly demonstrate the optical durability of candidate reflector materials in real-world service conditions, a network of instrumented outdoor exposure sites has been activated.

  12. Solar Concentrator Advanced Development Program, Task 1

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Solar dynamic power generation has been selected by NASA to provide power for the space station. Solar dynamic concentrator technology has been demonstrated for terrestrial applications but has not been developed for space applications. The object of the Solar Concentrator Advanced Development program is to develop the technology of solar concentrators which would be used on the space station. The first task of this program was to develop conceptual concentrator designs and perform trade-off studies and to develop a materials data base and perform material selection. Three unique concentrator concepts; Truss Hex, Spline Radial Panel and Domed Fresnel, were developed and evaluated against weighted trade criteria. The Truss Hex concept was recommended for the space station. Materials data base development demonstrated that several material systems are capable of withstanding extended periods of atomic oxygen exposure without undesirable performance degradation. Descriptions of the conceptual designs and materials test data are included.

  13. Advanced reflector materials for solar concentrators

    NASA Astrophysics Data System (ADS)

    Jorgensen, Gary; Williams, Tom; Wendelin, Tim

    1994-10-01

    This paper describes the research and development at the US National Renewable Energy Laboratory (NREL) in advanced reflector materials for solar concentrators. NREL's research thrust is to develop solar reflector materials that maintain high specular reflectance for extended lifetimes under outdoor service conditions and whose cost is significantly lower than existing products. Much of this work has been in collaboration with private-sector companies that have extensive expertise in vacuum-coating and polymer-film technologies. Significant progress and other promising developments will be discussed. These are expected to lead to additional improvements needed to commercialize solar thermal concentration systems and make them economically attractive to the solar manufacturing industry. To explicitly demonstrate the optical durability of candidate reflector materials in real-world service conditions, a network of instrumented outdoor exposure sites has been activated.

  14. Advanced oil burner for residential heating -- development report

    SciTech Connect

    Butcher, T.A.

    1995-07-01

    The development of advanced oil burner concepts has long been a part of Brookhaven National Laboratory`s (BNL) oil heat research program. Generally, goals of this work include: increased system efficiency, reduced emissions of soot and NO{sub x}, and the practical extension of the firing rate range of current burners to lower input rates. The report describes the results of a project at BNL aimed at the development of air atomized burners. Two concepts are discussed. The first is an air atomizer which uses air supplied at pressures ranging from 10 to 20 psi and requiring the integration of an air compressor in the system. The second, more novel, approach involves the use of a low-pressure air atomizing nozzle which requires only 8-14 inches of water air pressure for fuel atomization. This second approach requires the use of a fan in the burner instead of a compressor although the fan pressure is higher than with conventional, pressure atomized retention head burners. In testing the first concept, high pressure air atomization, a conventional retention head burner was modified to accept the new nozzle. In addition, the burner head was modified to reduce the flow area to maintain roughly 1 inch of water pressure drop across the head at a firing rate of 0.25 gallons of oil per hour. The burner ignited easily and could be operated at low excess air levels without smoke. The major disadvantage of this burner approach is the need for the air compressor as part of the system. In evaluating options, a vane-type compressor was selected although the use of a compressor of this type will lead to increased burner maintenance requirements.

  15. Calculating solar photovoltaic potential on residential rooftops in Kailua Kona, Hawaii

    NASA Astrophysics Data System (ADS)

    Carl, Caroline

    As carbon based fossil fuels become increasingly scarce, renewable energy sources are coming to the forefront of policy discussions around the globe. As a result, the State of Hawaii has implemented aggressive goals to achieve energy independence by 2030. Renewable electricity generation using solar photovoltaic technologies plays an important role in these efforts. This study utilizes geographic information systems (GIS) and Light Detection and Ranging (LiDAR) data with statistical analysis to identify how much solar photovoltaic potential exists for residential rooftops in the town of Kailua Kona on Hawaii Island. This study helps to quantify the magnitude of possible solar photovoltaic (PV) potential for Solar World SW260 monocrystalline panels on residential rooftops within the study area. Three main areas were addressed in the execution of this research: (1) modeling solar radiation, (2) estimating available rooftop area, and (3) calculating PV potential from incoming solar radiation. High resolution LiDAR data and Esri's solar modeling tools and were utilized to calculate incoming solar radiation on a sample set of digitized rooftops. Photovoltaic potential for the sample set was then calculated with the equations developed by Suri et al. (2005). Sample set rooftops were analyzed using a statistical model to identify the correlation between rooftop area and lot size. Least squares multiple linear regression analysis was performed to identify the influence of slope, elevation, rooftop area, and lot size on the modeled PV potential values. The equations built from these statistical analyses of the sample set were applied to the entire study region to calculate total rooftop area and PV potential. The total study area statistical analysis findings estimate photovoltaic electric energy generation potential for rooftops is approximately 190,000,000 kWh annually. This is approximately 17 percent of the total electricity the utility provided to the entire island in

  16. Advanced Solar Cells for Satellite Power Systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.; Weinberg, Irving

    1994-01-01

    The multiple natures of today's space missions with regard to operational lifetime, orbital environment, cost and size of spacecraft, to name just a few, present such a broad range of performance requirements to be met by the solar array that no single design can suffice to meet them all. The result is a demand for development of specialized solar cell types that help to optimize overall satellite performance within a specified cost range for any given space mission. Historically, space solar array performance has been optimized for a given mission by tailoring the features of silicon solar cells to account for the orbital environment and average operating conditions expected during the mission. It has become necessary to turn to entirely new photovoltaic materials and device designs to meet the requirements of future missions, both in the near and far term. This paper will outline some of the mission drivers and resulting performance requirements that must be met by advanced solar cells, and provide an overview of some of the advanced cell technologies under development to meet them. The discussion will include high efficiency, radiation hard single junction cells; monolithic and mechanically stacked multiple bandgap cells; and thin film cells.

  17. Performance criteria for solar heating and cooling systems in residential buildings

    NASA Astrophysics Data System (ADS)

    1982-09-01

    This performance criteria, developed for the Department of Housing and Urban Development, is a baseline document for criteria and standards for the design, development, technical evaluation, and procurement of solar heating and cooling systems for residential buildings in accordance with the requirements of Section 8 of Public Law 93-409, the Solar Heating and Cooling Demonstration Act of 1974. The document is intended to establish minimum levels of performance with regard to health and safety and the various aspects of technical performance. The criteria for health and safety put primary emphasis on compliance with existing codes and standards. The criteria on thermal and mechanical performance, durability/reliability and operation/servicing present performance requirements considered to be representative of acceptable levels.

  18. Comparative values of advanced space solar cells

    NASA Technical Reports Server (NTRS)

    Slifer, L. W., Jr.

    1982-01-01

    A methodology for deriving a first order dollar value estimate for advanced solar cells which consists of defining scenarios for solar array production and launch to orbit and the associated costs for typical spacecraft, determining that portion affected by cell design and performance and determining the attributable cost differences is presented. Break even values are calculated for a variety of cells; confirming that efficiency and related effects of radiation resistance and temperature coefficient are major factors; array tare mass, packaging and packing factor are important; but cell mass is of lesser significance. Associated dollar values provide a means of comparison.

  19. A low-cost-solar liquid desiccant system for residential cooling

    NASA Astrophysics Data System (ADS)

    Ware, Joel D., III

    The use of liquid desiccants for dehumidification of heating, ventilation, and air conditioning (HVAC) process air is becoming a more promising concept as the drive for energy conservation continues to grow. Recently, liquid desiccant systems have been implemented on the commercial level in conjunction with evaporative coolers and have recorded energy savings upwards of 50%. The aim of this research is to test the potential liquid desiccant systems have on the residential level when paired with a conventional vapor compression cycle and to construct a system that would overcome some of its barriers to the residential market. A complete low-cost-solar liquid desiccant system was designed, constructed, and tested in the Off-Grid Zero Emissions Building (OGZEB) at the Florida State University. Key design characteristics include turbulent process air flow through the conditioner and airside heating in the regenerator. The system was tested in the two following ways: (1) for the energy savings while maintaining a constant temperature over a twenty four hour period and (2) for the energy savings over a single cooling cycle. The liquid desiccant system achieved a maximum energy savings of 38% over a complete day and 52% over a single cooling cycle. It was projected that the system has the potential to save 1064 kWh over the course of a year. When combined with a renewable source of heat for regeneration, liquid desiccant systems become very cost effective. The levelized cost of energy for the combination of the liquid desiccant system and solar thermal collectors was calculated to be 7.06 C/kWh with a payback period of 4.4 years. This research provides evidence of the technology's potential on the residential sector and suggests ways for it to become competitive in the market.

  20. Construction of the Advanced Technology Solar Telescope

    NASA Astrophysics Data System (ADS)

    Rimmele, T. R.; Keil, S.; McMullin, J.; Knölker, M.; Kuhn, J. R.; Goode, P. R.; Rosner, R.; Casini, R.; Lin, H.; Tritschler, A.; Wöger, F.; ATST Team

    2012-12-01

    The 4m Advance Technology Solar Telescope (ATST) will be the most powerful solar telescope and the world's leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun's output. The project has entered its construction phase. Major subsystems have been contracted. As its highest priority science driver ATST shall provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4m aperture, ATST will resolve features at 0.″03 at visible wavelengths and obtain 0.″1 resolution at the magnetically highly sensitive near infrared wavelengths. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the Coudé laboratory facility. The initial set of first generation instruments consists of five facility class instruments, including imagers and spectro-polarimeters. The high polarimetric sensitivity and accuracy required for measurements of the illusive solar magnetic fields place strong constraints on the polarization analysis and calibration. Development and construction of a four-meter solar telescope presents many technical challenges, including thermal control of the enclosure, telescope structure and optics and wavefront control. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the design status of the telescope and its instrumentation, including design status of major subsystems, such as the telescope mount assembly, enclosure, mirror assemblies, and wavefront correction

  1. Impact of Rate Design Alternatives on Residential Solar Customer Bills. Increased Fixed Charges, Minimum Bills and Demand-based Rates

    SciTech Connect

    Bird, Lori; Davidson, Carolyn; McLaren, Joyce; Miller, John

    2015-09-01

    With rapid growth in energy efficiency and distributed generation, electric utilities are anticipating stagnant or decreasing electricity sales, particularly in the residential sector. Utilities are increasingly considering alternative rates structures that are designed to recover fixed costs from residential solar photovoltaic (PV) customers with low net electricity consumption. Proposed structures have included fixed charge increases, minimum bills, and increasingly, demand rates - for net metered customers and all customers. This study examines the electricity bill implications of various residential rate alternatives for multiple locations within the United States. For the locations analyzed, the results suggest that residential PV customers offset, on average, between 60% and 99% of their annual load. However, roughly 65% of a typical customer's electricity demand is non-coincidental with PV generation, so the typical PV customer is generally highly reliant on the grid for pooling services.

  2. AMUSE: an advanced ATM platform for residential interactive and distributive television

    NASA Astrophysics Data System (ADS)

    Di Concetto, M.; Gallassi, G.; Rosa, C.

    1996-12-01

    There is presently a strong expectation for the opportunities offered by the deployment of new and sophisticated telecommunication services with increasing interactivity, ranging from distributive to highly interactive, covering heterogeneous areas, like entertainment, tourism, commercial and information. The Project AMUSE (Advanced MUltimedia SErvices to residential users), which s being carried out in the framework of the Advanced Communication Technologies and Services Programme sponsored by the European Union, is proposing effective solutions to various open issues related to the implementation and provisioning of new multimedia services. After an overview of the project and the relevant platform, the paper will introduce a description of the advanced services the project is going to provide to real residential users by means of a state-of-then-art Asynchronous Transfer Mode end-to-end infrastructure. Emphasis will be put on the outcomes of the experiences gained during the first project year, stemming from the implementation and deployment of complex multimedia services developed by means of innovative authoring tools. Particular attention will be paid to the facts and findings resulting from the activities so far performed in the Italian trial island. In particular, the role of contents provisioning and service design, as well as the monitoring of service acceptance and usability by the final users are emerging as outstanding topics, even beyond network technological issues. Finally, an outline of major unsolved problems in the area of interactive multimedia s presented.

  3. National Program for Solar Heating and Cooling of Buildings. Project Date Summaries. Vol. I: Commercial and Residential Demonstrations.

    ERIC Educational Resources Information Center

    Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

    Three volumes present brief abstracts of projects funded by the Energy Research and Development Administration (ERDA) and conducted under the National Program for Solar Heating and Cooling of Buildings through July 1976. The overall federal program includes demonstrations of heating and/or combined cooling for residential and commercial buildings…

  4. Feasibility Study of Residential Grid-Connected Solar Photovoltaic Systems in the State of Indiana

    NASA Astrophysics Data System (ADS)

    Al-Odeh, Mahmoud

    This study aims to measure the financial viability of installing and using a residential grid-connected PV system in the State of Indiana while predicting its performance in eighteen geographical locations within the state over the system's expected lifetime. The null hypothesis of the study is that installing a PV system for a single family residence in the State of Indiana will not pay for itself within 25 years. Using a systematic approach consisting of six steps, data regarding the use of renewable energy in the State of Indiana was collected from the website of the US Department of Energy to perform feasibility analysis of the installation and use of a standard-sized residential PV system. The researcher was not able to reject the null hypothesis that installing a PV system for a single family residence in the State of Indiana will not pay for itself within 25 years. This study found that the standard PV system does not produce a positive project balance and does not pay for itself within 25 years (the life time of the system) assuming the average cost of a system. The government incentive programs are not enough to offset the cost of installing the system against the cost of the electricity that would not be purchased from the utility company. It can be concluded that the cost of solar PV is higher than the market valuation of the power it produces; thus, solar PV did not compete on the cost basis with the traditional competitive energy sources. Reducing the capital cost will make the standard PV system economically viable in Indiana. The study found that the capital cost for the system should be reduced by 15% - 56%.

  5. SOLCOST. Solar Hot Water Handbook. A Simplified Design Method for Sizing and Costing Residential and Commercial Solar Service Hot Water Systems. Second Edition.

    ERIC Educational Resources Information Center

    Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

    This pamphlet offers a preview of information services available from Solcost, a research and development project. The first section explains that Solcost calculates system and costs performance for solar heated and cooled new and retrofit constructions, such as residential buildings and single zone commercial buildings. For a typical analysis,…

  6. Advanced high efficiency wraparound contact solar cell

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.; Uno, F. M.; Thornhill, J. W.

    1977-01-01

    A significant advancement in the development of thin high efficiency wraparound contact silicon solar cells has been made by coupling space and terrestrial processing procedures. Although this new method for fabricating cells has not been completely reduced to practice, some of the initial cells have delivered over 20 mW/sq cm when tested at 25 C under AMO intensity. This approach not only yields high efficiency devices, but shows promise of allowing complete freedom of choice in both the location and size of the wraparound contact pad area

  7. Advanced high efficiency wraparound contact solar cell

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.; Uno, F. M.; Thornhill, J. W.

    1977-01-01

    A significant advancement in the development of thin high efficiency wraparound contact silicon solar cells has been made by coupling space and terrestrial processing procedures. Although this new method for fabricating cells has not been completely reduced to practice, some of the initial cells have delivered over 20 mW/sq cm when tested at 25 C under AMO intensity. This approach not only yields high efficiency devices, but shows promise of allowing complete freedom of choice in both the location and size of the wraparound contact pad area.

  8. Solar thermoelectricity via advanced latent heat storage

    NASA Astrophysics Data System (ADS)

    Olsen, M. L.; Rea, J.; Glatzmaier, G. C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, A. D.; Bobela, D.; Bonner, R.; Weigand, R.; Campo, D.; Parilla, P. A.; Siegel, N. P.; Toberer, E. S.; Ginley, D. S.

    2016-05-01

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a "thermal valve," which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  9. Solar concentrator advanced development program. Final report

    SciTech Connect

    Knasel, D.; Ehresman, D.

    1989-10-01

    The Solar Concentrator Advanced Development Project has successfully designed, fabricated, and tested a full scale prototypical solar dynamic concentrator for space station applications. A Truss Hexagonal Panel reflector was selected as a viable solar concentrator concept to be used for space station applications. This concentrator utilizes a modular design approach and is flexible in attainable flux profiles and assembly techniques. The detailed design of the concentrator, which included structural, thermal and optical analysis, identified the feasibility of the design and specific technologies that were required to fabricate it. The needed surface accuracy of the reflectors surface was found to be very tight, within 5 mrad RMS slope error, and results in very close tolerances for fabrication. To meet the design requirements, a modular structure composed of hexagonal panels was used. The panels, made up of graphite epoxy box beams provided the strength, stiffness and dimensional stability needed. All initial project requirements were met or exceeded by hardware demonstration. Initial testing of structural repeatability of a seven panel portion of the concentrator was followed by assembly and testing of the full nineteen panel structure. The testing, which consisted of theodolite and optical measurements over an assembly-disassembly-reassembly cycle, demonstrated that the concentrator maintained the as-built contour and optical characteristics. The facet development effort within the project, which included developing the vapor deposited reflective facet, produced a viable design with demonstrated optical characteristics that are within the project goals.

  10. Solar Thermoelectricity via Advanced Latent Heat Storage

    SciTech Connect

    Olsen, Michele L.; Rea, J.; Glatzmaier, Greg C.; Hardin, C.; Oshman, C.; Vaughn, J.; Roark, T.; Raade, J. W.; Bradshaw, R. W.; Sharp, J.; Avery, Azure D.; Bobela, David; Bonner, R.; Weigand, R.; Campo, D.; Parilla, Philip A.; Siegel, N. P.; Toberer, Eric S.; Ginley, David S.

    2016-05-31

    We report on a new modular, dispatchable, and cost-effective solar electricity-generating technology. Solar ThermoElectricity via Advanced Latent heat Storage (STEALS) integrates several state-of-the-art technologies to provide electricity on demand. In the envisioned STEALS system, concentrated sunlight is converted to heat at a solar absorber. The heat is then delivered to either a thermoelectric (TE) module for direct electricity generation, or to charge a phase change material for thermal energy storage, enabling subsequent generation during off-sun hours, or both for simultaneous electricity production and energy storage. The key to making STEALS a dispatchable technology lies in the development of a 'thermal valve,' which controls when heat is allowed to flow through the TE module, thus controlling when electricity is generated. The current project addresses each of the three major subcomponents, (i) the TE module, (ii) the thermal energy storage system, and (iii) the thermal valve. The project also includes system-level and techno- economic modeling of the envisioned integrated system and will culminate in the demonstration of a laboratory-scale STEALS prototype capable of generating 3kWe.

  11. Advanced Photovoltaic Solar Array program status

    NASA Technical Reports Server (NTRS)

    Kurland, Richard M.; Stella, Paul M.

    1989-01-01

    The Advanced Photolvoltaic Solar Array (APSA) Program is discussed. The objective of the program is to demonstrate a producible array system by the end of this decade with a beginning-of-life (BOL) specific power of 130 W/kg at 10 kW as an intermediate milestone toward the ultimate goal of 300 W/kg at 25 kW by the year 2000. The near-term goal represents a significant improvement over existing rigid panel flight arrays (25 to 45 W/kg) and the first-generation flexible blanket NASA/OAST SAFE I array of the early 1980s, which was projected to provide about 60 W/kg BOL. The prototype wing hardware is in the last stages of fabrication and integration. The current status of the program is reported. The array configuration and key design details are shown. Projections are shown for future performance enhancements that may be expected through the use of advanced structural components and solar cells.

  12. Development of a solar-powered residential air conditioner: Screening analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Screening analysis aimed at the definition of an optimum configuration of a Rankine cycle solar-powered air conditioner designed for residential application were conducted. Initial studies revealed that system performance and cost were extremely sensitive to condensing temperature and to the type of condenser used in the system. Consequently, the screening analyses were concerned with the generation of parametric design data for different condenser approaches; i. e., (1) an ambient air condenser, (2) a humidified ambient air condenser (3) an evaporative condenser, and (4) a water condenser (with a cooling tower). All systems feature a high performance turbocompressor and a single refrigerant (R-11) for the power and refrigeration loops. Data were obtained by computerized methods developed to permit system characterization over a broad range of operating and design conditions. The criteria used for comparison of the candidate system approaches were (1) overall system COP (refrigeration effect/solar heat input), (2) auxiliary electric power for fans and pumps, and (3) system installed cost or cost to the user.

  13. Integrated window systems: An advanced energy-efficient residential fenestration product

    SciTech Connect

    Arasteh, D.; Griffith, B.; LaBerge, P.

    1994-03-01

    The last several years have produced a wide variety of new window products aimed at reducing the energy impacts associated with residential windows. Improvements have focused on reducing the rate at which heat flows through the total window product by conduction/convection and thermal radiation (quantified by the U-factor) as well as in controlling solar heat gain (measured by the Solar Heat Gain Coefficient (SHGC) or Shading Coefficient (SC)). Significant improvements in window performance have been made with low-E coated glazings, gas fills in multiple pane windows and with changes in spacer and frame materials and designs. These improvements have been changes to existing design concepts. They have pushed the limits of the individual features and revealed weaknesses. The next generation of windows will have to incorporate new materials and ideas, like recessed night insulation, seasonal sun shades and structural window frames, into the design, manufacturing and construction process, to produce an integrated window system that will be an energy and comfort asset.

  14. Residential Solar Combined Heat and Power Generation using Solar Thermoelectric Generation

    NASA Astrophysics Data System (ADS)

    Ohara, B.; Wagner, M.; Kunkle, C.; Watson, P.; Williams, R.; Donohoe, R.; Ugarte, K.; Wilmoth, R.; Chong, M. Zachary; Lee, H.

    2015-06-01

    Recent reports on improved efficiencies of solar thermoelectric generation (STEG) systems have generated interest in STEGs as a competitive power generation system. In this paper, the design of a combined cooling and power utilizing concentrated solar power is discussed. Solar radiation is concentrated into a receiver connected to thermoelectric modules, which are used as a topping cycle to generate power and high grade heat necessary to run an absorption chiller. Modeling of the overall system is discussed with experimental data to validate modeling results. A numerical modeling approach is presented which considers temperature variation of the source and sink temperatures and is used to maximize combined efficiency. A system is built with a demonstrated combined efficiency of 32% in actual working conditions with power generation of 3.1 W. Modeling results fell within 3% of the experimental results verifying the approach. An optimization study is performed on the mirror concentration ration and number of modules for thermal load matching and is shown to improve power generation to 26.8 W.

  15. Installed Cost Benchmarks and Deployment Barriers for Residential Solar Photovoltaics with Energy Storage: Q1 2016

    SciTech Connect

    Ardani, Kristen; O'Shaughnessy, Eric; Fu, Ran; McClurg, Chris; Huneycutt, Joshua; Margolis, Robert

    2016-12-01

    In this report, we fill a gap in the existing knowledge about PV-plus-storage system costs and value by providing detailed component- and system-level installed cost benchmarks for residential systems. We also examine other barriers to increased deployment of PV-plus-storage systems in the residential sector. The results are meant to help technology manufacturers, installers, and other stakeholders identify cost-reduction opportunities and inform decision makers about regulatory, policy, and market characteristics that impede solar plus storage deployment. In addition, our periodic cost benchmarks will document progress in cost reductions over time. To analyze costs for PV-plus-storage systems deployed in the first quarter of 2016, we adapt the National Renewable Energy Laboratory's component- and system-level cost-modeling methods for standalone PV. In general, we attempt to model best-in-class installation techniques and business operations from an installed-cost perspective. In addition to our original analysis, model development, and review of published literature, we derive inputs for our model and validate our draft results via interviews with industry and subject-matter experts. One challenge to analyzing the costs of PV-plus-storage systems is choosing an appropriate cost metric. Unlike standalone PV, energy storage lacks universally accepted cost metrics, such as dollars per watt of installed capacity and lifetime levelized cost of energy. We explain the difficulty of arriving at a standard approach for reporting storage costs and then provide the rationale for using the total installed costs of a standard PV-plus-storage system as our primary metric, rather than using a system-size-normalized metric.

  16. The Advanced Technology Solar Telescope enclosure

    NASA Astrophysics Data System (ADS)

    Phelps, L.; Barr, J.; Dalrymple, N.; Fraser, M.; Hubbard, R.; Wagner, J.; Warner, M.

    2006-06-01

    Telescope enclosure design is based on an increasingly standard set of criteria. Enclosures must provide failsafe protection in a harsh environment for an irreplaceable piece of equipment; must allow effective air flushing to minimize local seeing while still attenuating wind-induced vibration of the telescope; must reliably operate so that the dome is never the reason for observatory down time; must provide access to utilities, lifting devices and support facilities; and they must be affordable within the overall project budget. The enclosure for the Advanced Technology Solar Telescope (ATST) has to satisfy all these challenging requirements plus one more. To eliminate so-called external dome seeing, the exterior surfaces of the enclosure must be maintained at or just below ambient air temperature while being subjected to the full solar loading of an observing day. Further complicating the design of the ATST enclosure and support facilities are the environmental sensitivities and high construction costs at the selected site - the summit of Haleakala on the island of Maui, Hawaii. Previous development work has determined an appropriate enclosure shape to minimize solar exposure while allowing effective interior flushing, and has demonstrated the feasibility of controlling the exterior skin temperature with an active cooling system. This paper presents the evolution of the design since site selection and how the enclosure and associated thermal systems have been tailored to the particular climatic and terrain conditions of the site. Also discussed are load-reduction strategies that have been identified through thermal modeling, CFD modeling, and other analyses to refine and economize the thermal control systems.

  17. Advanced photovoltaic solar array - Design and performance

    NASA Technical Reports Server (NTRS)

    Kurland, Richard; Stella, Paul

    1992-01-01

    This paper reports on the development of an ultralightweight flexible blanket, flatpack, foldout solar array design that can provide 3- to 4-fold improvement on specific power performance of current rigid panel arrays and a factor of two improvement over a first-generation flexible blanket array developed as a forerunner to the Space Station Freedom array. To date a prototype wing has been built with a projected specific power performance of about 138 W/kg at beginning-of-life (BOL) and 93 W/kg end-of-life (EOL) at 12 kW (BOL) for a 10-year geosynchronous (GEO) mission. The prototype wing hardware has been subjected to a series of system-level tests to demonstrate design feasibility. The design of the array is summarized. The major trade studies that led to the selection of the baseline design are discussed. Key system-level and component-level testing are described. Array-level performance projections are presented as a function of existing and advanced solar array component technology for various mission applications.

  18. ADVANCED THIN-FILM SOLAR CELLS.

    DTIC Science & Technology

    SEMICONDUCTING FILMS), (* SOLAR CELLS , GALLIUM ARSENIDES, TRANSPORT PROPERTIES, SUBSTRATES, MASS SPECTROSCOPY, CAPACITANCE, PREPARATION, PROCESSING, LABORATORY FURNACES, IMPURITIES, STABILITY, OXIDES.

  19. Instructor's Manual for Teaching and Practical Courses on Design of Systems and Sizing, Installation and Operation of Systems for Solar Heating and Cooling of Residential Buildings.

    ERIC Educational Resources Information Center

    Colorado State Univ., Ft. Collins. Solar Energy Applications Lab.

    Presented are guidelines for instructors of two courses in the design, installation, and operation of solar heating and cooling systems. These courses are: (1) Design of Systems, and (2) Sizing, Installation, and Operation of Systems. Limited in scope to active solar systems for residential buildings, these courses place primary emphasis upon…

  20. Research opportunities to advance solar energy utilization.

    PubMed

    Lewis, Nathan S

    2016-01-22

    Major developments, as well as remaining challenges and the associated research opportunities, are evaluated for three technologically distinct approaches to solar energy utilization: solar electricity, solar thermal, and solar fuels technologies. Much progress has been made, but research opportunities are still present for all approaches. Both evolutionary and revolutionary technology development, involving foundational research, applied research, learning by doing, demonstration projects, and deployment at scale will be needed to continue this technology-innovation ecosystem. Most of the approaches still offer the potential to provide much higher efficiencies, much lower costs, improved scalability, and new functionality, relative to the embodiments of solar energy-conversion systems that have been developed to date.

  1. Invited commentary: integrating a life-course perspective and social theory to advance research on residential segregation and health.

    PubMed

    Osypuk, Theresa L

    2013-02-15

    Research on racial residential segregation and health typically uses multilevel, population-based, slice-in-time data. Although research using this approach, including that by Kershaw et al. (Am J Epidemiol. 2013;177(4):299-309), has been valuable, I argue that to advance our understanding of how residential segregation influences health and health disparities, it is critical to incorporate a life-course perspective and integrate social theory. Applying a life-course perspective would entail modeling transitions, cumulative risk, and developmental and dynamic processes and mechanisms, as well as recognizing the contingency of contextual effects on different social groups. I discuss the need for analytic methods appropriate for modeling health effects of distal causes experienced across the life course, such as segregation, that operate through multiple levels and sequences of mediators, potentially across decades. Sociological theories of neighborhood attainment (e.g., segmented assimilation, ethnic resurgence, and place stratification theories) can guide effect-modification tests to help illuminate health effects resulting from intersections of residential processes, race/ethnicity, immigration, and other social determinants of health. For example, nativity and immigration history may crucially shape residential processes and exposures, but these have received limited attention in prior segregation-health literature.

  2. Break-Even Cost for Residential Solar Water Heating in the United States: Key Drivers and Sensitivities

    SciTech Connect

    Cassard, H.; Denholm, P.; Ong, S.

    2011-02-01

    This paper examines the break-even cost for residential rooftop solar water heating (SWH) technology, defined as the point where the cost of the energy saved with a SWH system equals the cost of a conventional heating fuel purchased from the grid (either electricity or natural gas). We examine the break-even cost for the largest 1,000 electric and natural gas utilities serving residential customers in the United States as of 2008. Currently, the break-even cost of SWH in the United States varies by more than a factor of five for both electricity and natural gas, despite a much smaller variation in the amount of energy saved by the systems (a factor of approximately one and a half). The break-even price for natural gas is lower than that for electricity due to a lower fuel cost. We also consider the relationship between SWH price and solar fraction and examine the key drivers behind break-even costs. Overall, the key drivers of the break-even cost of SWH are a combination of fuel price, local incentives, and technical factors including the solar resource location, system size, and hot water draw.

  3. ADVANCED THIN-FILM SOLAR CELLS.

    DTIC Science & Technology

    SEMICONDUCTING FILMS), (* SOLAR CELLS , MANUFACTURING, GALLIUM ALLOYS, ARSENIC ALLOYS, PLATINUM, OXIDES, TRANSPORT PROPERTIES, MOLYBDENUM, METAL FILMS, COPPER, HYDROGEN, GERMANIUM ALLOYS, TIN ALLOYS, ZINC, CRYSTAL GROWTH.

  4. Design, fabrication and test of block 4 design solar cell modules. Part 2: Residential module

    NASA Technical Reports Server (NTRS)

    Jester, T. L.

    1982-01-01

    Design, fabrication and test of the Block IV residential load module are reported. Design changes from the proposed module design through three iterations to the discontinuance of testing are outlined.

  5. Critical analysis about solutions and models of solar shades in non-residential buildings from tropical regions.

    PubMed

    Castañon, J A B; Caldeira, L F D; Gervásio, M F; Brum, F M

    2012-01-01

    Whereas the non-residential buildings consume a significant percentage of the total energy produced by the city, is important that these buildings have for such consumption is reduced or consumed in a conscious way. To do so, using concepts of energy efficiency, this work is to explain passive strategies with the use of flexible solar shades that help to get a favorable outcome with respect to the performance of the building right in the initial stages of planning and design. Once initial gains can be obtained and the architecture constants that value at the same time provide better working conditions and indoor comfort.

  6. A degree-day method for residential heating load calculations specifically incorporating the utilization of solar gains

    SciTech Connect

    Lucas, R.G.; Pratt, R.G.

    1990-09-01

    A simple and well known method of estimating residential heating loads is the variable base degree-day method, in which the steady-state heat loss rate (UA) is multiplied by the degree-days based from the balance temperature of the structure. The balance temperature is a function of the UA as well as the average rate of internal heat gains, reflecting the displacement of the heating requirements by these gains. Currently, the heat gains from solar energy are lumped with those from appliances to estimate an average rate over the day. This ignores the effects of the timing of the gains from solar energy, which are more highly concentrated during daytime hours, hence more frequently exceeding the required space heat and less utilizable than the gains from appliances. Simulations or specialized passive solar energy calculation methods have previously been required to account for this effect. This paper presents curves of the fraction of the absorbed solar energy utilized for displacement of space heat, developed by comparing heating loads calculated using a variable base degree-day method (ignoring solar gains) to heating loads from a large number of detailed DOE-2 simulations. The difference in the loads predicted by the two methods can be interpreted as the utilized solar gains. The solar utilization decreases as the thermal integrity increases, as expected, and the solar utilizations are similar across climates. They can be used to estimate the utilized fraction of the absorbed solar energy and, with the load predicted by the variable base degree-day calculation, form a modified degree-day method that closely reproduces the loads predicted by the DOE-2 simulation model and is simple enough for hand calculations. 6 refs., 6 figs., 2 tabs.

  7. Advanced solar energy conversion. [solar pumped gas lasers

    NASA Technical Reports Server (NTRS)

    Lee, J. H.

    1981-01-01

    An atomic iodine laser, a candidate for the direct solar pumped lasers, was successfully excited with a 4 kW beam from a xenon arc solar simulator, thus proving the feasibility of the concept. The experimental set up and the laser output as functions of operating conditions are presented. The preliminary results of the iodine laser amplifier pumped with the HCP array to which a Q switch for giant pulse production was coupled are included. Two invention disclosures - a laser driven magnetohydrodynamic generator for conversion of laser energy to electricity and solar pumped gas lasers - are also included.

  8. Advances in Solar Radiometry and Metrology

    SciTech Connect

    Myers, D.; Andreas, A.; Reda, I.; Gotseff, P.; Wilcox, S.; Stoffel, T.; Anderberg, M.

    2005-01-01

    The Solar Radiometry and Metrology task at the National Renewable Energy Laboratory (NREL) provides traceable optical radiometric calibrations and measurements to photovoltaic (PV) researchers and the PV industry. Traceability of NREL solar radiometer calibrations to the World Radiometric Reference (WRR) was accomplished during the NREL Pyrheliometer Comparison in October 2003. The task has calibrated 10 spectral and more than 180 broadband radiometers for solar measurements. Other accomplishments include characterization of pyranometer thermal offset errors with laboratory and spectral modeling tools; developing a simple scheme to correct pyranometer data for known responsivity variations; and measuring detailed spectral distributions of the NREL High Intensity Pulsed Solar Simulator (HIPSS) as a function of lamp voltage and time. The optical metrology functions support the NREL Measurement and Characterization Task effort for ISO 17025 accreditation of NREL Solar Reference Cell Calibrations. Optical metrology functions have been integrated into the NREL quality system and audited for ISO17025 compliance.

  9. Advanced research in solar energy storage

    NASA Astrophysics Data System (ADS)

    Luft, W.

    1983-01-01

    This paper gives an overview of the Solar Energy Storage Program at the Solar Energy Research Institute. The program provides research, systems analyses, and economic assessments of thermal and thermochemical energy storage and transport. Current activities include experimental research into very high temperature (above 800 C) thermal energy storage and assessment of novel thermochemical energy storage and transport systems. The applications for such high-temperature storage are thermochemical processes, solar thermal-electric power generation, cogeneration of heat and electricity, industrial process heat, and thermally regenerative electrochemical systems. The research results for five high-temperature thermal energy storage technologies and two thermochemical systems are described.

  10. Advanced crystallization techniques of 'solar grade' silicon

    NASA Astrophysics Data System (ADS)

    Gasparini, M.; Calligarich, C.; Rava, P.; Sardi, L.; Alessandri, M.; Redaelli, F.; Pizzini, S.

    Microstructural, electrical and photo-voltaic characteristics of polycrystal line silicon solar cells fabricated with silicon ingots containing 5, 100 and 500 ppmw iron are reported and discussed. All silicon ingots were grown by the directional solidification technique in graphite or special quartz molds and doped intentionally with iron, in order to evaluate the potentiality of the D.S. technique when employed with solar silicon feedstocks. Results indicate that structural breakdown limits the amount of the ingot which is usable for solar cells fabrication, but also that efficiencies in excess of 10 percent are obtained using the 'good' region of the ingot.

  11. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.; Richter, P. H.

    1980-01-01

    The performance and cost of four 10 MWe advanced solar thermal electric power plants sited in various regions of the continental United States was studied. Each region has different insolation characteristics which result in varying collector field areas, plant performance, capital costs and energy costs. The regional variation in solar plant performance was assessed in relation to the expected rise in the future cost of residential and commercial electricity supplied by conventional utility power systems in the same regions. A discussion of the regional insolation data base is presented along with a description of the solar systems performance and costs. A range for the forecast cost of conventional electricity by region and nationally over the next several decades is given.

  12. Technology assessment of solar energy systems: residential use of fuelwood in the Pacific Northwest

    SciTech Connect

    Petty, P.N.; Hopp, W.J.

    1981-08-01

    The evidence of impacts associated with the use of fuelwood for residential space heating in the region including the states of Washington, Oregon, and Idaho is identified and evaluated. The use of fuelwood for space heating was projected into the future, and then the potential size of the impacts that had been identified and estimated was evaluated. These projections are provided in five year increments beginning in 1980 and proceeding to the year 2000. Policy options are suggested which may mitigate the adverse impacts identified, while preserving the positive effect of reducing residential demand for energy derived from nonrenewable sources.

  13. Brayton cycle solarized advanced gas turbine

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Described is the development of a Brayton Engine/Generator Set for solar thermal to electrical power conversion, authorized under DOE/NASA Contract DEN3-181. The objective was to design, fabricate, assemble, and test a small, hybrid, 20-kW Brayton-engine-powered generator set. The latter, called a power conversion assembly (PCA), is designed to operate with solar energy obtained from a parobolic dish concentrator, 11 meters in diameter, or with fossil energy supplied by burning fuels in a combustor, or by a combination of both (hybrid model). The CPA consists of the Brayton cycle engine, a solar collector, a belt-driven 20-kW generator, and the necessary control systems for automatic operation in solar-only, fuel-only, and hybrid modes to supply electrical power to a utility grid. The original configuration of the generator set used the GTEC Model GTP36-51 gas turbine engine for the PCA prime mover. However, subsequent development of the GTEC Model AGT101 led to its selection as the powersource for the PCA. Performance characteristics of the latter, thermally coupled to a solar collector for operation in the solar mode, are presented. The PCA was successfully demonstrated in the fuel-only mode at the GTEC Phoenix, Arizona, facilities prior to its shipment to Sandia National Laboratory in Albuquerque, New Mexico, for installation and testing on a test bed concentractor (parabolic dish). Considerations relative to Brayton-engine development using the all-ceramic AGT101 when it becomes available, which would satisfy the DOE heat engine efficiency goal of 35 to 41 percent, are also discussed in the report.

  14. Non-Hardware ("Soft") Cost-Reduction Roadmap for Residential and Small Commercial Solar Photovoltaics, 2013-2020

    SciTech Connect

    Ardani, K.; Seif, D.; Margolis, R.; Morris, J.; Davidson, C.; Truitt, S.; Torbert, R.

    2013-08-01

    The objective of this analysis is to roadmap the cost reductions and innovations necessary to achieve the U.S. Department of Energy (DOE) SunShot Initiative's total soft-cost targets by 2020. The roadmap focuses on advances in four soft-cost areas: (1) customer acquisition; (2) permitting, inspection, and interconnection (PII); (3) installation labor; and (4) financing. Financing cost reductions are in terms of the weighted average cost of capital (WACC) for financing PV system installations, with real-percent targets of 3.0% (residential) and 3.4% (commercial).

  15. Plasma chamber testing of advanced photovoltaic solar array coupons

    NASA Astrophysics Data System (ADS)

    Hillard, G. Barry

    1994-05-01

    The solar array module plasma interactions experiment is a space shuttle experiment designed to investigate and quantify the high voltage plasma interactions. One of the objectives of the experiment is to test the performance of the Advanced Photovoltaic Solar Array (APSA). The material properties of array blanket are also studied as electric insulators for APSA arrays in high voltage conditions. Three twelve cell prototype coupons of silicon cells were constructed and tested in a space simulation chamber.

  16. Progress to Develop an Advanced Solar-Selective Coating

    SciTech Connect

    Kennedy, C. E.

    2008-03-01

    The progress to develop a durable advanced solar-selective coating will be described. Experimental work has focused on modeling high-temperature, solar-selective coatings; depositing the individual layers and modeled coatings; measuring the optical, thermal, morphology, and compositional properties and using the data to validate the modeled and deposited properties; re-optimizing the coating; and testing the coating performance and durability.

  17. The Trade-off between Solar Reflectance and Above-Sheathing Ventilation for Metal Roofs on Residential and Commercial Buildings

    SciTech Connect

    Desjarlais, Andre Omer; Kriner, Scott; Miller, William A

    2013-01-01

    An alternative to white and cool-color roofs that meets prescriptive requirements for steep-slope (residential and non-residential) and low-slope (non-residential) roofing has been documented. Roofs fitted with an inclined air space above the sheathing (herein termed above-sheathing ventilation, or ASV), performed as well as if not better than high-reflectance, high-emittance roofs fastened directly to the deck. Field measurements demonstrated the benefit of roofs designed with ASV. A computer tool was benchmarked against the field data. Testing and benchmarks were conducted at roofs inclined at 18.34 ; the roof span from soffit to ridge was 18.7 ft (5.7 m). The tool was then exercised to compute the solar reflectance needed by a roof equipped with ASV to exhibit the same annual cooling load as that for a direct-to-deck cool-color roof. A painted metal roof with an air space height of 0.75 in. (0.019 m) and spanning 18.7 ft (5.7 m) up the roof incline of 18.34 needed only a 0.10 solar reflectance to exhibit the same annual cooling load as a direct-to-deck cool-color metal roof (solar reflectance of 0.25). This held for all eight ASHRAE climate zones complying with ASHRAE 90.1 (2007a). A dark heat-absorbing roof fitted with 1.5 in. (0.038 m) air space spanning 18.7 ft (5.7 m) and inclined at 18.34 was shown to have a seasonal cooling load equivalent to that of a conventional direct-to-deck cool-color metal roof. Computations for retrofit application based on ASHRAE 90.1 (1980) showed that ASV air spaces of either 0.75 or 1.5 in. (0.019 and 0.038 m) would permit black roofs to have annual cooling loads equivalent to the direct-to-deck cool roof. Results are encouraging, and a parametric study of roof slope and ASV aspect ratio is needed for developing guidelines applicable to all steep- and low-slope roof applications.

  18. Recent advances in sensitized mesoscopic solar cells.

    PubMed

    Grätzel, Michael

    2009-11-17

    Perhaps the largest challenge for our global society is to find ways to replace the slowly but inevitably vanishing fossil fuel supplies by renewable resources and, at the same time, avoid negative effects from the current energy system on climate, environment, and health. The quality of human life to a large degree depends upon the availability of clean energy sources. The worldwide power consumption is expected to double in the next 3 decades because of the increase in world population and the rising demand of energy in the developing countries. This implies enhanced depletion of fossil fuel reserves, leading to further aggravation of the environmental pollution. As a consequence of dwindling resources, a huge power supply gap of 14 terawatts is expected to open up by year 2050 equaling today's entire consumption, thus threatening to create a planetary emergency of gigantic dimensions. Solar energy is expected to play a crucial role as a future energy source. The sun provides about 120,000 terawatts to the earth's surface, which amounts to 6000 times the present rate of the world's energy consumption. However, capturing solar energy and converting it to electricity or chemical fuels, such as hydrogen, at low cost and using abundantly available raw materials remains a huge challenge. Chemistry is expected to make pivotal contributions to identify environmentally friendly solutions to this energy problem. One area of great promise is that of solar converters generally referred to as "organic photovoltaic cells" (OPV) that employ organic constituents for light harvesting or charge carrier transport. While this field is still in its infancy, it is receiving enormous research attention, with the number of publications growing exponentially over the past decade. The advantage of this new generation of solar cells is that they can be produced at low cost, i.e., potentially less than 1 U.S. $/peak watt. Some but not all OPV embodiments can avoid the expensive and energy

  19. Advanced Solar Cell Testing and Characterization

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Curtis, Henry; Piszczor, Michael

    2005-01-01

    The topic for this workshop stems from an ongoing effort by the photovoltaic community and U.S. government to address issues and recent problems associated with solar cells and arrays experienced by a number of different space systems. In April 2003, a workshop session was held at the Aerospace Space Power Workshop to discuss an effort by the Air Force to update and standardize solar cell and array qualification test procedures in an effort to ameliorate some of these problems. The organizers of that workshop session thought it was important to continue these discussions and present this information to the entire photovoltaic community. Thus, it was decided to include this topic as a workshop at the following SPRAT conference.

  20. Comparison of solar heat pump systems to conventional methods for residential heating, cooling, and water heating, volume 2

    NASA Astrophysics Data System (ADS)

    Hughes, P. J.; Morehouse, J. H.

    1980-04-01

    The series and parallel combined solar heat pump systems investigated are at best marginally competitive, on a 20 year life cycle cost basis, with conventional oil and electric furnace systems. The combined solar heat pump systems are not economically competitive with conventional gas furnace or stand alone heat pump systems for residential space heating, cooling and water heating. The combined solar heat pump systems do offer the potential for significant energy savings as compared to conventional furnace systems and the stand alone heat pump. The cost of that savings, however, is beyond that which the average consumer can be expected to pay. Barring unforeseen manufacturing process or materials breakthroughs, parallel systems prices are firm. The prices listed for series systems already include low cost site built collectors and an optimistic estimate of the liquid to air heat pump costs, and prices on other series system components are firm. A collector cost sensitivity analysis did not offer any encouraging directions towards significant systems cost reduction.

  1. Advances In Understanding Solar And Stellar Flares

    NASA Astrophysics Data System (ADS)

    Kowalski, Adam F.

    2016-07-01

    Flares result from the sudden reconnection and relaxation of magnetic fields in the coronae of stellar atmospheres. The highly dynamic atmospheric response produces radiation across the electromagnetic spectrum, from the radio to X-rays, on a range of timescales, from seconds to days. New high resolution data of solar flares have revealed the intrinsic spatial properties of the flaring chromosphere, which is thought to be where the majority of the flare energy is released as radiation in the optical and near-UV continua and emission lines. New data of stellar flares have revealed the detailed properties of the broadband (white-light) continuum emission, which provides straightforward constraints for models of the transformation of stored magnetic energy in the corona into thermal energy of the lower atmosphere. In this talk, we discuss the physical processes that produce several important spectral phenomena in the near-ultraviolet and optical as revealed from new radiative-hydrodynamic models of flares on the Sun and low mass stars. We present recent progress with high-flux nonthermal electron beams in reproducing the observed optical continuum color temperature of T 10,000 K and the Balmer jump properties in the near-ultraviolet. These beams produce dense, heated chromospheric condensations, which can explain the shape and strength of the continuum emission in M dwarf flares and the red-wing asymmetries in the chromospheric emission lines in recent observations of solar flares from the Interface Region Imaging Spectrograph. Current theoretical challenges and future modeling directions will be discussed, as well as observational synergies between solar and stellar flares.

  2. Advanced materials manufacturing for solar energy

    NASA Astrophysics Data System (ADS)

    van Mierlo, Frank

    2012-02-01

    The US has a robust technical roadmap to get to a 1/W total installed cost with several potential winners in the race. We dominate in the new technology arena and there is a good chance that tomorrow's winning technology will be from the current crop of contenders. One potential breakthrough is Direct Wafer^TM a new manufacturing technique to make silicon wafers at a fraction of the traditional cost. Current wafer manufacturing is a multi-step, energy- and capital-intensive process that wastes half of the valuable silicon feedstock. 1366's Direct Wafer technology forms a standard, 156mm multi-crystalline wafer directly from molten silicon in a semi-continuous, efficient, high-throughput process that eliminates silicon waste. Direct Wafer^TM cuts the amount of consumables by a factor of four and requires only half the capital per GigaWatt production capacity thus enabling solar to compete successfully with coal generated electricity.

  3. Recent Advances in Solar Sail Propulsion at NASA

    NASA Technical Reports Server (NTRS)

    Johnson, Les; Young, Roy M.; Montgomery, Edward E., IV

    2006-01-01

    Supporting NASA's Science Mission Directorate, the In-Space Propulsion Technology Program is developing solar sail propulsion for use in robotic science and exploration of the solar system. Solar sail propulsion will provide longer on-station operation, increased scientific payload mass fraction, and access to previously inaccessible orbits for multiple potential science missions. Two different 20-meter solar sail systems were produced and successfully completed functional vacuum testing last year in NASA Glenn's Space Power Facility at Plum Brook Station, Ohio. The sails were designed and developed by ATK Space Systems and L'Garde, respectively. These sail systems consist of a central structure with four deployable booms that support the sails. This sail designs are robust enough for deployments in a one atmosphere, one gravity environment, and are scalable to much larger solar sails-perhaps as much as 150 meters on a side. In addition, computation modeling and analytical simulations have been performed to assess the scalability of the technology to the large sizes (>150 meters) required for first generation solar sails missions. Life and space environmental effects testing of sail and component materials are also nearly complete. This paper will summarize recent technology advancements in solar sails and their successful ambient and vacuum testing.

  4. Designing, building, and testing a solar thermoelectric generation, STEG, for energy delivery to remote residential areas in developing regions

    NASA Astrophysics Data System (ADS)

    Moumouni, Yacouba

    New alternatives and inventive renewable energy techniques which encompass both generation and power management solutions are fundamental for meeting remote residential energy supply and demand today, especially if the grid is quasi-inexistent. Solar thermoelectric generators can be a cost-effective alternative to photovoltaics for a remote residential household power supply. A complete solar thermoelectric energy harvesting system is presented for energy delivery to remote residential areas in developing regions. To this end, the entire system was built, modeled, and then validated with LTspice simulator software via thermal-to-electrical analogy schemes. Valuable data in conjunction with two novel LTspice circuits were obtained, showing the achievability of analyzing transient heat transfer with the Spice simulator. Hence, the proposed study begins with a comprehensive method of extracting thermal parameters that appear in thermoelectric modules. A step-by-step procedure was developed and followed to succinctly extract parameters, such as the Seebeck coefficient, electrical conductivity, thermal resistance, and thermal conductivity needed to model the system. Data extracted from datasheet, material properties, and geometries were successfully utilized to compute the thermal capacities and resistances necessary to perform the analogy. In addition, temperature variations of the intrinsic internal parameters were accounted for in this process for accuracy purposes. The steps that it takes to simulate any thermo-electrical system with the LTspice simulator are thoroughly explained in this work. As a consequence, an improved Spice model for a thermoelectric generator is proposed. Experimental results were compiled in the form of a lookup table and then fed into the Spice simulator using the piecewise linear (PWL) command in order to validate the model. Experimental results show that a temperature differential of 13.43°C was achievable whereas the simulation indicates

  5. A comparison of fuel savings in the residential and commercial sectors generated by the installation of solar heating and cooling systems under three tax credit scenarios

    NASA Astrophysics Data System (ADS)

    Moden, R.

    An analysis of expected energy savings between 1977 and 1980 under three different solar tax credit scenarios is presented. The results were obtained through the solar heating and cooling of buildings (SHACOB) commercialization model. This simulation provides projected savings of conventional fuels through the installation of solar heating and cooling systems on buildings in the residential and commercial sectors. The three scenarios analyzed considered the tax credits contained in the Windfall Profits Tax of April 1980, the National Tax Act of November 1978, and a case where no tax credit is in effect.

  6. Design, development and testing of a solar-powered multi-family residential size prototype turbocompressor heat pump

    SciTech Connect

    1981-03-01

    A program described to design, fabricate, and conduct preliminary testing of a prototype solar-powered Rankine cycle turbocompressor heat pump module for a multi-family residential building is presented. A solar system designed to use the turbocompressor heat pump module including all of the subsystems required and the various system operating modes is described in Section I. Section II includes the preliminary design analyses conducted to select the heat pump module components and operating features, working fluid, configuration, size and performance goals, and estimated performance levels in the cooling and heating modes. Section III provides a detailed description of the other subsystems and components required for a complete solar installation. Using realistic performance and cost characteristics for all subsystems, the seasonal performance of the UTC heat pump is described in various US locations. In addition, the estimated energy savings and an assessment of the economic viability of the solar system is presented in Section III. The detailed design of the heat pump module and the arrangement of components and controls selected to conduct the laboratory performance tests are described in Section IV. Section V provides a description of the special laboratory test facility, including the subsystems to simulate the collectors and storage tanks for building load and ambient conditions and the instrumentation, monitoring, and data acquisition equipment. The test results and sample computer analyses and comparisons with predicted performance levels are presented in Section VI. Various appendices provide supplementary and background information concerning working fluid selection (A), configuration selection (B), capacity control concepts (C), building models (D), computer programs used to determine component and system performance and total system economics (E), and weather data (F).

  7. Predicting Inner Heliospheric Solar Wind Conditions in Advance of Solar Probe Plus

    NASA Astrophysics Data System (ADS)

    Case, A. W.; Kasper, J. C.; Korreck, K. E.; Stevens, M. L.; Cohen, O.; Salem, C. S.; Halekas, J. S.; Larson, D. E.; Maruca, B. A.

    2012-12-01

    In advance of the upcoming inner heliospheric missions (Solar Orbiter and Solar Probe Plus) it is vital to have an accurate prediction of the range of solar wind conditions that occur between 9.5Rs and 0.7AU. These conditions will place constraints on instrument design and the operational modes that are used. In this paper, we discuss and compare different methods of predicting the solar wind bulk plasma parameters. One method uses observed 1AU conditions observed with the Wind spacecraft combined with scaling laws derived from Helios observations. We extend this simple model by using a more realistic solar wind velocity profile in addition to the Wind and Helios observations. Another method uses 3D MHD simulations from which solar wind conditions along a spacecraft trajectory can be extracted. We discuss some implications of these models in the design of the Solar Wind Electrons Alphas and Protons investigation, a suite of solar wind instruments being designed to fly on Solar Probe Plus.

  8. Chapter 1: Recent Advances in Solar Physics

    NASA Astrophysics Data System (ADS)

    Dwivedi, B. N.

    2008-10-01

    For millennia, the Sun (and the universe) has been viewed in the visual light. As the bestower of light and life, the ancients made God out of the Sun. With the Babylonians, or with the multiple origins with the Chinese, Egyptians and Indians, quoting the Rig Veda:"All that exists was born from Sūrya, the God of gods.", we have come a long way to understanding the Sun. In the early seventeenth century, however, Galileo showed that the Sun was not an immaculate object. Thus began our scientific interests in our nearest stellar neighbour, the Sun (cf., Figure 1.1.), with its sunspots and the related solar activity. The observations of the Sun and their interpretations are of universal importance for at least two reasons: First, the Sun is the source of energy for the entire planetary system and all aspects of our life have direct impact on what happens on the Sun; and second, the Sun's proximity makes it unique among the billions of stars in the sky of which we can resolve its surface features and study physical processes at work...

  9. Design and operation of a solar heating and cooling system for a residential size building

    NASA Technical Reports Server (NTRS)

    Littles, J. W.; Humphries, W. R.; Cody, J. C.

    1978-01-01

    The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner.

  10. Advanced solar concentrator mass production, operation, and maintenance cost assessment

    NASA Technical Reports Server (NTRS)

    Niemeyer, W. A.; Bedard, R. J.; Bell, D. M.

    1981-01-01

    The object of this assessment was to estimate the costs of the preliminary design at: production rates of 100 to 1,000,000 concentrators per year; concentrators per aperture diameters of 5, 10, 11, and 15 meters; and various receiver/power conversion package weights. The design of the cellular glass substrate Advanced Solar Concentrator is presented. The concentrator is an 11 meter diameter, two axis tracking, parabolic dish solar concentrator. The reflective surface of this design consists of inner and outer groups of mirror glass/cellular glass gores.

  11. Solar Power Satellite Development: Advances in Modularity and Mechanical Systems

    NASA Technical Reports Server (NTRS)

    Belvin, W. Keith; Dorsey, John T.; Watson, Judith J.

    2010-01-01

    Space solar power satellites require innovative concepts in order to achieve economically and technically feasible designs. The mass and volume constraints of current and planned launch vehicles necessitate highly efficient structural systems be developed. In addition, modularity and in-space deployment will be enabling design attributes. This paper reviews the current challenges of launching and building very large space systems. A building block approach is proposed in order to achieve near-term solar power satellite risk reduction while promoting the necessary long-term technology advances. Promising mechanical systems technologies anticipated in the coming decades including modularity, material systems, structural concepts, and in-space operations are described

  12. solar thermal power systems advanced solar thermal technology project, advanced subsystems development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

  13. Design package for a complete residential solar space heating and hot water system

    NASA Technical Reports Server (NTRS)

    1978-01-01

    Information necessary to evaluate the design of a solar space heating and hot water system is reported. System performance specifications, the design data brochure, the system description, and other information pertaining to the design are included.

  14. Thermal and economic assessment of ground-coupled storage for residential solar heat pump systems

    NASA Astrophysics Data System (ADS)

    Choi, M. K.; Morehouse, J. H.

    1980-11-01

    This study performed an analysis of ground-coupled stand-alone and series configured solar-assisted liquid-to-air heat pump systems for residences. The year-round thermal performance of these systems for space heating, space cooling, and water heating were determined by simulation and compared against non-ground-coupled solar heat pump systems as well as conventional heating and cooling systems in three geographic locations: Washington, D.C., Fort Worth, Tex., and Madison, Wis. The results indicate that without tax credits a combined solar/ground-coupled heat pump system for space heating and cooling is not cost competitive with conventional systems. Its thermal performance is considerably better than non-ground-coupled solar heat pumps in Forth Worth. Though the ground-coupled stand-alone heat pump provides 51% of the heating and cooling load with non-purchased energy in Forth Worth, its thermal performance in Washington and Madison is poor.

  15. System integration of marketable subsystems. [for residential solar heating and cooling

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Progress is reported in the following areas: systems integration of marketable subsystems; development, design, and building of site data acquisition subsystems; development and operation of the central data processing system; operation of the MSFC Solar Test Facility; and systems analysis.

  16. Residential solar energy: one family's experience with installation, performance, and cost

    NASA Astrophysics Data System (ADS)

    Carpenter, David; Aubrecht, Gordon; Aubrecht, Michelle

    2007-10-01

    ``Meet the Carpenters'' is Michelle Aubrecht's submission to Al Gore's global warming awareness contest. The 60-second ad focuses on the Carpenter family's efforts to reduce their personal carbon footprint. One major way is a solar panel installation David Carpenter installed on his family's south-facing roof. This poster will present the contest ad and give highlights of David Carpenter's energy and monetary savings from the solar roof as well as details about how net metering works in Ohio.

  17. Design, development and testing of a solar-powered multi-family residential-size prototype turbocompressor heat pump

    SciTech Connect

    Not Available

    1982-10-01

    An experimental program was conducted to further define, improve and demonstrate the performance characteristics and operational features of an existing 18-ton solar-powered prototype heat pump. The prototype heat pump is nominally sized for multi-family residential applications and provides both space heating and cooling. It incorporates a turbocompressor specially designed to operate at peak temperatures consistent with medium concentration collectors. The major efforts in this program phase included modification and improvement of the instrumentation sensors, the laboratory simulation equipment and selected heat pump components. After implementing these modifications, performance testing was conducted for a total operating time of approximately 250 hours. Experimental test results compared favorably with performance data calculated using the UTRC computer prediction program for the same boundary conditions. A series of tests was conducted continuously over a 12-h period to simulate operation (in the cooling mode) of the prototype heat pump under conditions typical of an actual installation. The test demonstrated that the heat pump could match the cooling load profile of a multi-family residential building. During the system performance testing, sufficient data were taken to identify the performance of each of the major components (e.g. turbine, compressor, heat exchangers, R11 pump). Component performance is compared with that calculated using the UTRC computer predict program and with data supplied by their manufacturers. The performance capabilities of the prototype heat pump system have been documented and recommendations are made for further design improvements which could be included in a MOD-2 configuration. The MOD-2 configuration would incorporate features that would improve system performance, reduce capital cost and most importantly improve system reliability.

  18. Advance care planning for older people in Australia presenting to the emergency department from the community or residential aged care facilities.

    PubMed

    Street, Maryann; Ottmann, Goetz; Johnstone, Megan-Jane; Considine, Julie; Livingston, Patricia M

    2015-09-01

    The purpose of this retrospective, cross-sectional study was to determine the prevalence of advance care planning (ACP) among older people presenting to an Emergency Department (ED) from the community or a residential aged care facility. The study sample comprised 300 older people (aged 65+ years) presenting to three Victorian EDs in 2011. A total of 150 patients transferred from residential aged care to ED were randomly selected and then matched to 150 people who lived in the community and attended the ED by age, gender, reason for ED attendance and triage category on arrival. Overall prevalence of ACP was 13.3% (n = 40/300); over one-quarter (26.6%, n = 40/150) of those presenting to the ED from residential aged care had a documented Advance Care Plan, compared to none (0%, n = 0/150) of the people from the community. There were no significant differences in the median ED length of stay, number of investigations and interventions undertaken in ED, time seen by a doctor or rate of hospital admission for those with an Advance Care Plan compared to those without. Those with a comorbidity of cerebrovascular disease or dementia and those assessed with impaired brain function were more likely to have a documented Advance Care Plan on arrival at ED. Length of hospital stay was shorter for those with an Advance Care Plan [median (IQR) = 3 days (2-6) vs. 6 days (2-10), P = 0.027] and readmission lower (0% vs. 13.7%). In conclusion, older people from the community transferred to ED were unlikely to have a documented Advance Care Plan. Those from residential aged care who were cognitively impaired more frequently had an Advance Care Plan. In the ED, decisions of care did not appear to be influenced by the presence or absence of Advance Care Plans, but length of hospital admission was shorter for those with an Advance Care Plan.

  19. Development of a solar-powered residential air conditioner: Economic analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The results of investigations aimed at the development of cost models to be used in the economic assessment of Rankine-powered air conditioning systems for residential application are summarized. The rationale used in the development of the cost model was to: (1) collect cost data on complete systems and on the major equipment used in these systems; (2) reduce these data and establish relationships between cost and other engineering parameters such as weight, size, power level, etc; and (3) derive simple correlations from which cost-to-the-user can be calculated from performance requirements. The equipment considered in the survey included heat exchangers, fans, motors, and turbocompressors. This kind of hardware represents more than 2/3 of the total cost of conventional air conditioners.

  20. Advanced solar concentrator development in the United States

    NASA Astrophysics Data System (ADS)

    Alpert, Daniel J.

    Sandia National Laboratories is the lead laboratory for the United States Department of Energy's program to develop, build, and test advanced solar concentrators that are low in cost, have high performance, and demonstrate a long lifetime. The principal focus of DOE's concentrator program is on the development of heliostats for central receiver power plants and point focus parabolic dishes for use with a 25-kWe Stirling engine. The status and future plans of DOE's program in each area are reviewed.

  1. Development of a solar-powered residential air conditioner: System optimization preliminary specification

    NASA Technical Reports Server (NTRS)

    Rousseau, J.; Hwang, K. C.

    1975-01-01

    Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

  2. Here Comes the Sun! Residential Solar Systems Add up to Savings

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2007-01-01

    Every day, the sun showers the planet with millions of times more energy that its people use. The only problem is that the energy is spread out over the entire earth's surface and thus must be harvested. Engineers are learning to capture and use some of this energy to make electricity for homes. A well-designed solar system can last for 20 years…

  3. Comparison of Advanced Residential Water Heating Technologies in the United States

    SciTech Connect

    Maguire, J.; Fang, X.; Wilson, E.

    2013-05-01

    Gas storage, gas tankless, condensing, electric storage, heat pump, and solar water heaters were simulated in several different climates across the US installed in both conditioned and unconditioned space and subjected to several different draw profiles. While many preexisting models were used, new models of condensing and heat pump water heaters were created specifically for this work.

  4. Solar collection

    NASA Astrophysics Data System (ADS)

    Cole, S. I.

    1984-08-01

    Solar dishes, photovoltaics, passive solar building and solar hot water systems, Trombe walls, hot air panels, hybrid solar heating systems, solar grain dryers, solar greenhouses, solar hot water worhshops, and solar workshops are discussed. These solar technologies are applied to residential situations.

  5. Advanced Technology Solar Telescope lower enclosure thermal system

    NASA Astrophysics Data System (ADS)

    Phelps, L.; Warner, M.

    2008-07-01

    The exterior of the Advanced Technology Solar Telescope enclosure requires cooling to eliminate so-called external dome seeing caused by solar loading during the observing day. This is achieved by way of coolant circulation through external plate coil panels, thereby maintaining the exterior surfaces of the enclosure at or just below ambient air temperature. As the distance from the optical path increases (e.g., on the surface of the lower enclosure), the stringency of the temperature requirement is diminished, thereby allowing a greater difference between the surface temperature and the ambient air temperature. This paper presents a comparison of the modeled performance of an active thermal control strategy on the lower enclosure to a passive strategy that employs concrete panels. A life-cycle cost analysis of each option is also presented.

  6. Update of the Solar Concentrator Advanced Development Project

    NASA Technical Reports Server (NTRS)

    Corrigan, Robert D.; Peterson, Todd T.; Ehresman, Derik T.

    1989-01-01

    The Solar Concentrator Advanced Development Project, which has achieved the successful design, fabrication, and testing of a full-scale prototypical solar dynamic concentrator, is discussed. The design and fabrication process are summarized, and the test results for the reflective facet optical performance and the concentrator structural repeatability are reported. Initial testing of structural repeatability of a seven panel portion of the concentrator was followed by assembly and testing of the full nineteen-panel structure. The testing, which consisted of theodolite and optical measurements over an assembly-disassembly-reassembly cycle, demonstrated that the concentrator maintained the as-built contour and optical characteristics. The facet development effort, which entailed developing a vapor-deposited reflective facet, produced a viable design with demonstrated optical characteristics that are within the project goals.

  7. Advanced Receiver tracking of Voyager 2 near solar conjunction

    NASA Technical Reports Server (NTRS)

    Brown, D. H.; Hurd, W. J.; Vilnrotter, V. A.; Wiggins, J. D.

    1988-01-01

    The Advanced Receiver (ARX) was used to track the Voyager 2 spacecraft at low Sun-Earth-Probe (SEP) angles near solar conjunction in December of 1987. The received carrier signal exhibited strong fluctuations in both phase and amplitude. The ARX used spectral estimation and mathematical modeling of the phase and receiver noise processes to set an optimum carrier tracking bandwidth. This minimized the mean square phase error in tracking carrier phase and thus minimized the loss in the telemetry signal-to-noise ratio due to the carrier loop. Recovered symbol SNRs and errors in decoded engineering data for the ARX are compared with those for the current Block 3 telemetry stream. Optimum bandwidths are plotted against SEP angle. Measurements of the power spectral density of the solar phase and amplitude fluctuations are also given.

  8. The Advanced Technology Solar Telescope: beginning construction of the world's largest solar telescope

    NASA Astrophysics Data System (ADS)

    Rimmele, T. R.; Wagner, J.; Keil, S.; Elmore, D.; Hubbard, R.; Hansen, E.; Warner, M.; Jeffers, P.; Phelps, L.; Marshall, H.; Goodrich, B.; Richards, K.; Hegwer, S.; Kneale, R.; Ditsler, J.

    2010-07-01

    The 4m Advance Technology Solar Telescope (ATST) will be the most powerful solar telescope and the world's leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun's output. The project has successfully passed its final design review and the Environmental Impact Study for construction of ATST on Haleakala, Maui, HI has been concluded in December of 2009. The project is now entering its construction phase. As its highest priority science driver ATST shall provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4 m aperture, ATST will resolve features at 0."03 at visible wavelengths and obtain 0."1 resolution at the magnetically highly sensitive near infrared wavelengths. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the coudé laboratory facility. The initial set of first generation instruments consists of five facility class instruments, including imagers and spectropolarimeters. The high polarimetric sensitivity and accuracy required for measurements of the illusive solar magnetic fields place strong constraints on the polarization analysis and calibration. Development and construction of a fourmeter solar telescope presents many technical challenges, including thermal control of the enclosure, telescope structure and optics and wavefront control. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the design status of the telescope and its instrumentation, including design status of major subsystems, such as the telescope mount assembly, enclosure, mirror assemblies, and wavefront correction

  9. Comparison of Advanced Residential Water Heating Technologies in the United States

    SciTech Connect

    Maguire, Jeff; Fang, Xia; Wilson, Eric

    2013-05-01

    In this study, gas storage, gas tankless, condensing, electric storage, heat pump, and solar water heaters were simulated in several different climates across the United States, installed in both conditioned and unconditioned space and subjected to several different draw profiles. While many pre-existing models were used, new models of condensing and heat pump water heaters were created specifically for this work. In each case modeled, the whole house was simulated along with the water heater to capture any interactions between the water heater and the space conditioning equipment.

  10. Multiple-etalon systems for the Advanced Technology Solar Telescope

    NASA Technical Reports Server (NTRS)

    Gary, G. Allen; Balasubramaniam, K. S.; Sigwarth, Michael

    2003-01-01

    Multiple etalon systems are discussed that meet the science requirements for a narrow-passband imaging system for the 4-meter National Solar Observatory (NSO)/Advance Technology Solar Telescope (ATST). A multiple etalon system can provide an imaging interferometer that works in four distinct modes: as a spectro-polarimeter, a filter-vector magnetograph, an intermediate-band imager, and broadband high-resolution imager. Specific dual and triple etalon configurations are described that provide a spectrographic passband of 2.0-3.5 micron and reduce parasitic light levels to 10(exp -4) as required for precise polarization measurement, e.g., Zeeman measurements of magnetic sensitive lines. A TESOS-like (Telecentric Etalon SOlar Spectrometer) triple etalon system provides a spectral purity of 10(exp -5). The triple designs have the advantage of reducing the finesse requirement on each etalon; allow the use of more stable blocking filters, and have very high spectral purity. A dual-etalon double-pass (Cavallini-like) system can provide a competing configuration. Such a dual-etalon design can provide high contrast. The selection of the final focal plane instrument will depend on a trade-off between an ideal instrument and practical reality. The trade study will include the number of etalons, their aperture sizes, complexities of the optical train, number of blocking filters, configuration of the electronic control system, computer interfaces, temperature controllers, etalon controllers, and their associated feedback electronics. The heritage of single and multiple etalon systems comes from their use in several observatories, including the Marshall Space Flight Center (MSFC) Solar Observatory, Sacramento Peak Observatory (NSO), and Kiepenheuer-Institut fur Sonnenphysik (KIS, Germany), Mees Solar Observatory (University of Hawaii), and Arcetri Astrophysical Observatory (Italy). The design of the ATST multiple etalon system will benefit from the experience gained at these

  11. Multiple Etalon Systems for the Advanced Technology Solar Telescope

    NASA Technical Reports Server (NTRS)

    Gary, G. Allen; Balasubramaniam, K. S.; Sigwarth, Michael; Six, N. Frank (Technical Monitor)

    2002-01-01

    Multiple etalons systems are discussed that meet the 4-meter NSO/Advance Technology Solar Telescope (http://www.nso.edu/ATST/index.html) instrument and science requirements for a narrow bandpass imaging system. A multiple etalon system can provide an imaging interferometer working in four distinct modes: as a spectro-polarimeter, a filter-vector magnetograph, and a wide-band and broad-band high-resolution imager. Specific dual and triple etalon configurations will be described that provides spectrographic passband of 2.0-3.5nm and reduces parasitic light levels to 1/10000 as required by precise polarization measurement, e.g., Zeeman measurements of magnetic sensitive lines. A TESOS-like triple etalon system provides for spectral purity of 100 thousandths. The triple designs have the advantage of reducing the finesse requirement on each etalon, allowing much more stable blocking filters, and can have very high spectral purity. A dual-etalon double-pass Cavallini-like configuration can provide a competing configuration. This design can provide high contrast with only a double etalon. The selection of the final focal plan instrument will depend on a trade-off of the ideal instrument versus reality, the number of etalons, the aperture of etalons, the number of blocking filters the electronic control system and computer interfaces, the temperature control and controllers for the etalons and the electronics. The use of existing experience should provide significant cost savings. The heritage of use of etalons and multiple etalon systems in solar physics come from a number of observatories, which includes MSFC Solar Observatory (NASA), Sac Peak Observatory (NSO), and Kiepenheuer Institute for Solar Physics (Germany), Mees Solar Observatory (University of Hawaii), and Arcetri Astrophysical Observatory (Italy). The design of the ATST multiple etalon system will reply on the existing experience from these observatories.

  12. Fuzzy logic controller versus classical logic controller for residential hybrid solar-wind-storage energy system

    NASA Astrophysics Data System (ADS)

    Derrouazin, A.; Aillerie, M.; Mekkakia-Maaza, N.; Charles, J. P.

    2016-07-01

    Several researches for management of diverse hybrid energy systems and many techniques have been proposed for robustness, savings and environmental purpose. In this work we aim to make a comparative study between two supervision and control techniques: fuzzy and classic logics to manage the hybrid energy system applied for typical housing fed by solar and wind power, with rack of batteries for storage. The system is assisted by the electric grid during energy drop moments. A hydrogen production device is integrated into the system to retrieve surplus energy production from renewable sources for the household purposes, intending the maximum exploitation of these sources over years. The models have been achieved and generated signals for electronic switches command of proposed both techniques are presented and discussed in this paper.

  13. Technology development of fabrication techniques for advanced solar dynamic concentrators

    NASA Technical Reports Server (NTRS)

    Richter, Scott W.

    1991-01-01

    The objective of the advanced concentrator program is to develop the technology that will lead to lightweight, highly reflective, accurate, scaleable, and long lived space solar dynamic concentrators. The advanced concentrator program encompasses new and innovative concepts, fabrication techniques, materials selection, and simulated space environmental testing. Fabrication techniques include methods of fabricating the substrates and coating substrate surfaces to produce high quality optical surfaces, acceptable for further coating with vapor deposited optical films. The selected materials to obtain a high quality optical surface include microsheet glass and Eccocoat EP-3 epoxy, with DC-93-500 selected as a candidate silicone adhesive and levelizing layer. The following procedures are defined: cutting, cleaning, forming, and bonding microsheet glass. Procedures are also defined for surface cleaning, and EP-3 epoxy application. The results and analyses from atomic oxygen and thermal cycling tests are used to determine the effects of orbital conditions in a space environment.

  14. Use of Advanced Solar Cells for Commercial Communication Satellites

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Landis, Geoffrey A.

    1995-01-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  15. Use of advanced solar cells for commercial communication satellites

    NASA Astrophysics Data System (ADS)

    Bailey, Sheila G.; Landis, Geoffrey A.

    1995-03-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  16. Use of advanced solar cells for commerical communication satellites

    NASA Astrophysics Data System (ADS)

    Landis, Geoffrey A.; Bailey, Sheila G.

    1995-01-01

    The current generation of communications satellites are located primarily in geosynchronous Earth orbit (GEO). Over the next decade, however, a new generation of communications satellites will be built and launched, designed to provide a world-wide interconnection of portable telephones. For this mission, the satellites must be positioned in lower polar- and near-polar orbits. To provide complete coverage, large numbers of satellites will be required. Because of the required number of satellites decreases as the orbital altitude is increased, fewer satellites would be required if the orbit chosen were raised from Low to intermediate orbit. However, in intermediate orbits, satellites encounter significant radiation due to trapped electrons and protons. Radiation tolerant solar cells may be necessary to make such satellites feasible. We analyze the amount of radiation encountered in low and intermediate polar orbits at altitudes of interest to next-generation communication satellites, calculate the expected degradation for silicon, GaAs, and InP solar cells, and show that the lifetimes can be significantly increased by use of advanced solar cells.

  17. Interfacial Materials for Organic Solar Cells: Recent Advances and Perspectives.

    PubMed

    Yin, Zhigang; Wei, Jiajun; Zheng, Qingdong

    2016-08-01

    Organic solar cells (OSCs) have shown great promise as low-cost photovoltaic devices for solar energy conversion over the past decade. Interfacial engineering provides a powerful strategy to enhance efficiency and stability of OSCs. With the rapid advances of interface layer materials and active layer materials, power conversion efficiencies (PCEs) of both single-junction and tandem OSCs have exceeded a landmark value of 10%. This review summarizes the latest advances in interfacial layers for single-junction and tandem OSCs. Electron or hole transporting materials, including metal oxides, polymers/small-molecules, metals and metal salts/complexes, carbon-based materials, organic-inorganic hybrids/composites, and other emerging materials, are systemically presented as cathode and anode interface layers for high performance OSCs. Meanwhile, incorporating these electron-transporting and hole-transporting layer materials as building blocks, a variety of interconnecting layers for conventional or inverted tandem OSCs are comprehensively discussed, along with their functions to bridge the difference between adjacent subcells. By analyzing the structure-property relationships of various interfacial materials, the important design rules for such materials towards high efficiency and stable OSCs are highlighted. Finally, we present a brief summary as well as some perspectives to help researchers understand the current challenges and opportunities in this emerging area of research.

  18. Interfacial Materials for Organic Solar Cells: Recent Advances and Perspectives

    PubMed Central

    Yin, Zhigang; Wei, Jiajun

    2016-01-01

    Organic solar cells (OSCs) have shown great promise as low‐cost photovoltaic devices for solar energy conversion over the past decade. Interfacial engineering provides a powerful strategy to enhance efficiency and stability of OSCs. With the rapid advances of interface layer materials and active layer materials, power conversion efficiencies (PCEs) of both single‐junction and tandem OSCs have exceeded a landmark value of 10%. This review summarizes the latest advances in interfacial layers for single‐junction and tandem OSCs. Electron or hole transporting materials, including metal oxides, polymers/small‐molecules, metals and metal salts/complexes, carbon‐based materials, organic‐inorganic hybrids/composites, and other emerging materials, are systemically presented as cathode and anode interface layers for high performance OSCs. Meanwhile, incorporating these electron‐transporting and hole‐transporting layer materials as building blocks, a variety of interconnecting layers for conventional or inverted tandem OSCs are comprehensively discussed, along with their functions to bridge the difference between adjacent subcells. By analyzing the structure–property relationships of various interfacial materials, the important design rules for such materials towards high efficiency and stable OSCs are highlighted. Finally, we present a brief summary as well as some perspectives to help researchers understand the current challenges and opportunities in this emerging area of research. PMID:27812480

  19. Final Report: Towards an Emergent Model of Technology Adoption for Accelerating the Diffusion of Residential Solar PV

    SciTech Connect

    Rai, Varun

    2016-08-15

    This project sought to enable electric utilities in Texas to accelerate diffusion of residential solar photovoltaic (PV) by systematically identifying and targeting existing barriers to PV adoption. A core goal of the project was to develop an integrated research framework that combines survey research, econometric modeling, financial modeling, and implementation and evaluation of pilot projects to study the PV diffusion system. This project considered PV diffusion as an emergent system, with attention to the interactions between the constituent parts of the PV socio-technical system including: economics of individual decision-making; peer and social influences; behavioral responses; and information and transaction costs. We also conducted two pilot projects, which have yielded new insights into behavioral and informational aspects of PV adoption. Finally, this project has produced robust and generalizable results that will provide deeper insights into the technology-diffusion process that will be applicable for the design of utility programs for other technologies such as home-energy management systems and plug-in electric vehicles. When we started this project in 2013 there was little systematic research on characterizing the decision-making process of households interested in adopting PV. This project was designed to fill that research gap by analyzing the PV adoption process from the consumers' decision-making perspective and with the objective to systematically identifying and addressing the barriers that consumers face in the adoption of PV. The two key components of that decision-making process are consumers' evaluation of: (i) uncertainties and non-monetary costs associated with the technology and (ii) the direct monetary cost-benefit. This project used an integrated approach to study both the non-monetary and the monetary components of the consumer decision-making process.

  20. The Advanced Technology Solar Telescope: design and early construction

    NASA Astrophysics Data System (ADS)

    McMullin, Joseph P.; Rimmele, Thomas R.; Keil, Stephen L.; Warner, Mark; Barden, Samuel; Bulau, Scott; Craig, Simon; Goodrich, Bret; Hansen, Eric; Hegwer, Steve; Hubbard, Robert; McBride, William; Shimko, Steve; Wöger, Friedrich; Ditsler, Jennifer

    2012-09-01

    The National Solar Observatory’s (NSO) Advanced Technology Solar Telescope (ATST) is the first large U.S. solar telescope accessible to the worldwide solar physics community to be constructed in more than 30 years. The 4-meter diameter facility will operate over a broad wavelength range (0.35 to 28 μm ), employing adaptive optics systems to achieve diffraction limited imaging and resolve features approximately 20 km on the Sun; the key observational parameters (collecting area, spatial resolution, spectral coverage, polarization accuracy, low scattered light) enable resolution of the theoretically-predicted, fine-scale magnetic features and their dynamics which modulate the radiative output of the sun and drive the release of magnetic energy from the Sun’s atmosphere in the form of flares and coronal mass ejections. In 2010, the ATST received a significant fraction of its funding for construction. In the subsequent two years, the project has hired staff and opened an office on Maui. A number of large industrial contracts have been placed throughout the world to complete the detailed designs and begin constructing the major telescope subsystems. These contracts have included the site development, AandE designs, mirrors, polishing, optic support assemblies, telescope mount and coudé rotator structures, enclosure, thermal and mechanical systems, and high-level software and controls. In addition, design development work on the instrument suite has undergone significant progress; this has included the completion of preliminary design reviews (PDR) for all five facility instruments. Permitting required for physically starting construction on the mountaintop of Haleakalā, Maui has also progressed. This paper will review the ATST goals and specifications, describe each of the major subsystems under construction, and review the contracts and lessons learned during the contracting and early construction phases. Schedules for site construction, key factory testing of

  1. A Model for Infusing Energy Concepts into Vocational Education Programs. Advanced Solar Systems.

    ERIC Educational Resources Information Center

    Delta Vocational Technical School, Marked Tree, AR.

    This instructional unit consists of materials designed to help students understand terms associated with solar energy; identify components of advanced solar systems; and identify applications of solar energy in business, industry, agriculture, and photovoltaics. Included in the unit are the following materials: suggested activities, instructional…

  2. Advancing aged care: a systematic review of economic evaluations of workforce structures and care processes in a residential care setting.

    PubMed

    Easton, Tiffany; Milte, Rachel; Crotty, Maria; Ratcliffe, Julie

    2016-01-01

    Long-term care for older people is provided in both residential and non-residential settings, with residential settings tending to cater for individuals with higher care needs. Evidence relating to the costs and effectiveness of different workforce structures and care processes is important to facilitate the future planning of residential aged care services to promote high quality care and to enhance the quality of life of individuals living in residential care. A systematic review conducted up to December 2015 identified 19 studies containing an economic component; seven included a complete economic evaluation and 12 contained a cost analysis only. Key findings include the potential to create cost savings from a societal perspective through enhanced staffing levels and quality improvement interventions within residential aged care facilities, while integrated care models, including the integration of health disciplines and the integration between residents and care staff, were shown to have limited cost-saving potential. Six of the 19 identified studies examined dementia-specific structures and processes, in which person-centred interventions demonstrated the potential to reduce agitation and improve residents' quality of life. Importantly, this review highlights methodological limitations in the existing evidence and an urgent need for future research to identify appropriate and meaningful outcome measures that can be used at a service planning level.

  3. Solar photovoltaic systems

    NASA Technical Reports Server (NTRS)

    Forney, R. G.

    1978-01-01

    The Department of Energy's photovoltaic program is outlined. The main objective of the program is the development of low cost reliable terrestrial photovoltaic systems. A second objective is to foster widespread use of the system in residential, industrial and commercial application. The system is reviewed by examining each component; silicon solar cell, silicon solar cell modules, advanced development modules and power systems. Cost and applications of the system are discussed.

  4. Projected techno-economic improvements for advanced solar thermal power plants

    NASA Technical Reports Server (NTRS)

    Fujita, T.; Manvi, R.; Roschke, E. J.

    1979-01-01

    The projected characteristics of solar thermal power plants (with outputs up to 10 MWe) employing promising advanced technology subsystems/components are compared to current (or pre-1985) steam-Rankine systems. Improvements accruing to advanced technology development options are delineated. The improvements derived from advanced systems result primarily from achieving high efficiencies via solar collector systems which (1) capture a large portion of the available insolation and (2) concentrate this captured solar flux to attain high temperatures required for high heat engine/energy conversion performance. The most efficient solar collector systems employ two-axis tracking. Attractive systems include the central receiver/heliostat and the parabolic dish.

  5. The Implementation of Advanced Solar Array Technology in Future NASA Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F.; Kerslake, Thomas W.; Hoffman, David J.; White, Steve; Douglas, Mark; Spence, Brian; Jones, P. Alan

    2003-01-01

    Advanced solar array technology is expected to be critical in achieving the mission goals on many future NASA space flight programs. Current PV cell development programs offer significant potential and performance improvements. However, in order to achieve the performance improvements promised by these devices, new solar array structures must be designed and developed to accommodate these new PV cell technologies. This paper will address the use of advanced solar array technology in future NASA space missions and specifically look at how newer solar cell technologies impact solar array designs and overall power system performance.

  6. Microgravity fluid management requirements of advanced solar dynamic power systems

    NASA Technical Reports Server (NTRS)

    Migra, Robert P.

    1987-01-01

    The advanced solar dynamic system (ASDS) program is aimed at developing the technology for highly efficient, lightweight space power systems. The approach is to evaluate Stirling, Brayton and liquid metal Rankine power conversion systems (PCS) over the temperature range of 1025 to 1400K, identify the critical technologies and develop these technologies. Microgravity fluid management technology is required in several areas of this program, namely, thermal energy storage (TES), heat pipe applications and liquid metal, two phase flow Rankine systems. Utilization of the heat of fusion of phase change materials offers potential for smaller, lighter TES systems. The candidate TES materials exhibit large volume change with the phase change. The heat pipe is an energy dense heat transfer device. A high temperature application may transfer heat from the solar receiver to the PCS working fluid and/or TES. A low temperature application may transfer waste heat from the PCS to the radiator. The liquid metal Rankine PCS requires management of the boiling/condensing process typical of two phase flow systems.

  7. Design, evaluation and recommedation effort relating to the modification of a residential 3-ton absorption cycle cooling unit for operation with solar energy

    NASA Technical Reports Server (NTRS)

    Merrick, R. H.; Anderson, P. P.

    1973-01-01

    The possible use of solar energy powered absorption units to provide cooling and heating of residential buildings is studied. Both, the ammonia-water and the water-lithium bromide cycles, are considered. It is shown that the air cooled ammonia water unit does not meet the criteria for COP and pump power on the cooling cycle and the heat obtained from it acting as a heat pump is at too low a temperature. If the ammonia machine is water cooled it will meet the design criteria for cooling but can not supply the heating needs. The water cooled lithium bromide unit meets the specified performance for cooling with appreciably lower generator temperatures and without a mechanical solution pump. It is recommeded that in the demonstration project a direct expansion lithium bromide unit be used for cooling and an auxiliary duct coil using the solar heated water be employed for heating.

  8. Advanced Nanomaterials for High-Efficiency Solar Cells

    SciTech Connect

    Chen, Junhong

    2013-11-29

    Energy supply has arguably become one of the most important problems facing humankind. The exponential demand for energy is evidenced by dwindling fossil fuel supplies and record-high oil and gas prices due to global population growth and economic development. This energy shortage has significant implications to the future of our society, in addition to the greenhouse gas emission burden due to consumption of fossil fuels. Solar energy seems to be the most viable choice to meet our clean energy demand given its large scale and clean/renewable nature. However, existing methods to convert sun light into electricity are not efficient enough to become a practical alternative to fossil fuels. This DOE project aims to develop advanced hybrid nanomaterials consisting of semiconductor nanoparticles (quantum dots or QDs) supported on graphene for cost-effective solar cells with improved conversion efficiency for harvesting abundant, renewable, clean solar energy to relieve our global energy challenge. Expected outcomes of the project include new methods for low-cost manufacturing of hybrid nanostructures, systematic understanding of their properties that can be tailored for desired applications, and novel photovoltaic cells. Through this project, we have successfully synthesized a number of novel nanomaterials, including vertically-oriented graphene (VG) sheets, three-dimensional (3D) carbon nanostructures comprising few-layer graphene (FLG) sheets inherently connected with CNTs through sp{sup 2} carbons, crumpled graphene (CG)-nanocrystal hybrids, CdSe nanoparticles (NPs), CdS NPs, nanohybrids of metal nitride decorated on nitrogen-doped graphene (NG), QD-carbon nanotube (CNT) and QD-VG-CNT structures, TiO{sub 2}-CdS NPs, and reduced graphene oxide (RGO)-SnO{sub 2} NPs. We further assembled CdSe NPs onto graphene sheets and investigated physical and electronic interactions between CdSe NPs and the graphene. Finally we have demonstrated various applications of these

  9. Functional safety for the Advanced Technology Solar Telescope

    NASA Astrophysics Data System (ADS)

    Bulau, Scott; Williams, Timothy R.

    2012-09-01

    Since inception, the Advanced Technology Solar Telescope (ATST) has planned to implement a facility-wide functional safety system to protect personnel from harm and prevent damage to the facility or environment. The ATST will deploy an integrated safety-related control system (SRCS) to achieve functional safety throughout the facility rather than relying on individual facility subsystems to provide safety functions on an ad hoc basis. The Global Interlock System (GIS) is an independent, distributed, facility-wide, safety-related control system, comprised of commercial off-the-shelf (COTS) programmable controllers that monitor, evaluate, and control hazardous energy and conditions throughout the facility that arise during operation and maintenance. The GIS has been designed to utilize recent advances in technology for functional safety plus revised national and international standards that allow for a distributed architecture using programmable controllers over a local area network instead of traditional hard-wired safety functions, while providing an equivalent or even greater level of safety. Programmable controllers provide an ideal platform for controlling the often complex interrelationships between subsystems in a modern astronomical facility, such as the ATST. A large, complex hard-wired relay control system is no longer needed. This type of system also offers greater flexibility during development and integration in addition to providing for expanded capability into the future. The GIS features fault detection, self-diagnostics, and redundant communications that will lead to decreased maintenance time and increased availability of the facility.

  10. Photovoltaics for residential applications

    SciTech Connect

    Not Available

    1984-02-01

    Information is given about the parts of a residential photovoltaic system and considerations relevant to photovoltaic power use in homes that are also tied to utility lines. In addition, factors are discussed that influence implementation, including legal and environmental factors such as solar access and building codes, insurance, utility buyback, and system longevity. (LEW)

  11. The Impact of City-level Permitting Processes on Residential Photovoltaic Installation Prices and Development Times: An Empirical Analysis of Solar Systems in California Cities

    SciTech Connect

    Wiser, Ryan; Dong, Changgui

    2013-04-01

    Business process or “soft” costs account for well over 50% of the installed price of residential photovoltaic (PV) systems in the United States, so understanding these costs is crucial for identifying PV cost-reduction opportunities. Among these costs are those imposed by city-level permitting processes, which may add both expense and time to the PV development process. Building on previous research, this study evaluates the effect of city-level permitting processes on the installed price of residential PV systems and on the time required to develop and install those systems. The study uses a unique dataset from the U.S. Department of Energy’s Rooftop Solar Challenge Program, which includes city-level permitting process “scores,” plus data from the California Solar Initiative and the U.S. Census. Econometric methods are used to quantify the price and development-time effects of city-level permitting processes on more than 3,000 PV installations across 44 California cities in 2011. Results indicate that city-level permitting processes have a substantial and statistically significant effect on average installation prices and project development times. The results suggest that cities with the most favorable (i.e., highest-scoring) permitting practices can reduce average residential PV prices by $0.27–$0.77/W (4%–12% of median PV prices in California) compared with cities with the most onerous (i.e., lowest-scoring) permitting practices, depending on the regression model used. Though the empirical models for development times are less robust, results suggest that the most streamlined permitting practices may shorten development times by around 24 days on average (25% of the median development time). These findings illustrate the potential price and development-time benefits of streamlining local permitting procedures for PV systems.

  12. Solar extreme ultraviolet sensor and advanced langmuir probe

    NASA Technical Reports Server (NTRS)

    Voronka, N. R.; Block, B. P.; Carignan, G. R.

    1992-01-01

    For more than two decades, the staff of the Space Physics Research Laboratory (SPRL) has collaborated with the Goddard Space Flight Center (GSFC) in the design and implementation of Langmuir probes (LP). This program of probe development under the direction of Larry Brace of GSFC has evolved methodically with innovations to: improve measurement precision, increase the speed of measurement, and reduce the weight, size, power consumption and data rate of the instrument. Under contract NAG5-419 these improvements were implemented and are what characterize the Advanced Langmuir Probe (ALP). Using data from the Langmuir Probe on the Pioneer Venus Orbiter, Brace and Walter Hoegy of GSFC demonstrated a novel method of monitoring the solar extreme ultraviolet (EUV) flux. This led to the idea of developing a sensor similar to a Langmuir probe specifically designed to measure solar EUV (SEUV) that uses a similar electronics package. Under this contract, a combined instrument package of the ALP and SEUV sensor was to be designed, constructed, and laboratory tested. Finally the instrument was to be flight tested as part of sounding rocket experiment to acquire the necessary data to validate this method for possible use in future earth and planetary aeronomy missions. The primary purpose of this contract was to develop the electronics hardware and software for this instrument, since the actual sensors were suppied by GSFC. Due to budget constraints, only a flight model was constructed. These electronics were tested and calibrated in the laboratory, and then the instrument was integrated into the rocket payload at Wallops Flight Facility where it underwent environmental testing. After instrument recalibration at SPRL, the payload was reintegrated and launched from the Poker Flat Research Range near Fairbanks Alaska. The payload was successfully recovered and after refurbishment underwent further testing and developing to improve its performance for future use.

  13. Advanced Inverter Functions to Support High Levels of Distributed Solar: Policy and Regulatory Considerations (Brochure)

    SciTech Connect

    Not Available

    2014-11-01

    This paper explains how advanced inverter functions (sometimes called 'smart inverters') contribute to the integration of high levels of solar PV generation onto the electrical grid and covers the contributions of advanced functions to maintaining grid stability. Policy and regulatory considerations associated with the deployment of advanced inverter functions are also introduced.

  14. Advanced Electric Propulsion for Space Solar Power Satellites

    NASA Technical Reports Server (NTRS)

    Oleson, Steve

    1999-01-01

    The sun tower concept of collecting solar energy in space and beaming it down for commercial use will require very affordable in-space as well as earth-to-orbit transportation. Advanced electric propulsion using a 200 kW power and propulsion system added to the sun tower nodes can provide a factor of two reduction in the required number of launch vehicles when compared to in-space cryogenic chemical systems. In addition, the total time required to launch and deliver the complete sun tower system is of the same order of magnitude using high power electric propulsion or cryogenic chemical propulsion: around one year. Advanced electric propulsion can also be used to minimize the stationkeeping propulsion system mass for this unique space platform. 50 to 100 kW class Hall, ion, magnetoplasmadynamic, and pulsed inductive thrusters are compared. High power Hall thruster technology provides the best mix of launches saved and shortest ground to Geosynchronous Earth Orbital Environment (GEO) delivery time of all the systems, including chemical. More detailed studies comparing launch vehicle costs, transfer operations costs, and propulsion system costs and complexities must be made to down-select a technology. The concept of adding electric propulsion to the sun tower nodes was compared to a concept using re-useable electric propulsion tugs for Low Earth Orbital Environment (LEO) to GEO transfer. While the tug concept would reduce the total number of required propulsion systems, more launchers and notably longer LEO to GEO and complete sun tower ground to GEO times would be required. The tugs would also need more complex, longer life propulsion systems and the ability to dock with sun tower nodes.

  15. Development of an advanced solar augmented water heater (for single family home applications)

    NASA Astrophysics Data System (ADS)

    Grunes, H.; Morrison, D.; Dewinter, F.

    1982-06-01

    A program was undertaken to design, construct and test two advanced prototype solar augmented gas water heaters. Computer analyses and experimental work were used to optimize components and characterize performance. The resulting design includes a solar preheat tank, a gas-fired backup tank, the collector loop pump and all operating controls contained in a single cylindrical package. The backup tank is positioned above the solar preheat tank. The connection between the solar and backup tanks is effectively a thermal diode which restricts heat transfer from the backup to the solar tank but allows the backup tank to become an integral part of solar storage whenever the solar tank temperature surpasses the backup tank set point temperature. Solar heat is supplied through a jacketed tank drainback system.

  16. Assessing the Effectiveness of Residential Adult Education.

    ERIC Educational Resources Information Center

    Kafka, James J.; Griffith, William S.

    1984-01-01

    This study was conducted to investigate the aspects of residential adult education that might account for differences among the participants in residential programs. An analysis of the claims advanced by advocates of residential adult education led to the identification of three factors that appeared to account for the alleged superiority of this…

  17. Advanced Space Robotics and Solar Electric Propulsion: Enabling Technologies for Future Planetary Exploration

    NASA Astrophysics Data System (ADS)

    Kaplan, M.; Tadros, A.

    2017-02-01

    Obtaining answers to questions posed by planetary scientists over the next several decades will require the ability to travel further while exploring and gathering data in more remote locations of our solar system. Timely investments need to be made in developing and demonstrating solar electric propulsion and advanced space robotics technologies.

  18. A measurement of the shape of the solar disk: The solar quadrupole moment, the solar octopole moment, and the advance of perihelion of the planet mercury

    SciTech Connect

    Lydon, T.J.; Sofia, S.

    1996-01-01

    The Solar Disk Sextant experiment has measured the solar angular diameter for a variety of solar latitudes. Combined with solar surface angular rotation data, the solar quadrupole moment {ital J}{sub 2} and the solar octopole moment {ital J}{sub 4} have been derived first by assuming constant internal angular rotation on cylinders and then by assuming constant internal angular rotation on cones. We have derived values of 1.8{times}10{sup {minus}7} for {ital J}{sub 2} and 9.8{times}10{sup {minus}7} for {ital J}{sub 4}. We conclude with a discussion of errors and address the prediction of general relativity for the rate of advance of perihelion of the planet Mercury. {copyright} {ital 1996 The American Physical Society.}

  19. Final Technical Report Advanced Solar Resource Modeling and Analysis.

    SciTech Connect

    Hansen, Clifford

    2015-12-01

    The SunShot Initiative coordinates research, development, demonstration, and deployment activities aimed at dramatically reducing the total installed cost of solar power. The SunShot Initiative focuses on removing critical technical and non-technical barriers to installing and integrating solar energy into the electricity grid. Uncertainty in projected power and energy production from solar power systems contributes to these barriers by increasing financial risks to photovoltaic (PV) deployment and by exacerbating the technical challenges to integration of solar power on the electricity grid.

  20. Advanced Solar-propelled Cargo Spacecraft for Mars Missions

    NASA Technical Reports Server (NTRS)

    Auziasdeturenne, Jacqueline; Beall, Mark; Burianek, Joseph; Cinniger, Anna; Dunmire, Barbrina; Haberman, Eric; Iwamoto, James; Johnson, Stephen; Mccracken, Shawn; Miller, Melanie

    1989-01-01

    Three concepts for an unmanned, solar powered, cargo spacecraft for Mars support missions were investigated. These spacecraft are designed to carry a 50,000 kg payload from a low Earth orbit to a low Mars orbit. Each design uses a distinctly different propulsion system: A Solar Radiation Absorption (SRA) system, a Solar-Pumped Laser (SPL) system and a solar powered magnetoplasmadynamic (MPD) arc system. The SRA directly converts solar energy to thermal energy in the propellant through a novel process. In the SPL system, a pair of solar-pumped, multi-megawatt, CO2 lasers in sunsynchronous Earth orbit converts solar energy to laser energy. The MPD system used indium phosphide solar cells to convert sunlight to electricity, which powers the propulsion system. Various orbital transfer options are examined for these concepts. In the SRA system, the mother ship transfers the payload into a very high Earth orbit and a small auxiliary propulsion system boosts the payload into a Hohmann transfer to Mars. The SPL spacecraft and the SPL powered spacecraft return to Earth for subsequent missions. The MPD propelled spacecraft, however, remains at Mars as an orbiting space station. A patched conic approximation was used to determine a heliocentric interplanetary transfer orbit for the MPD propelled spacecraft. All three solar-powered spacecraft use an aerobrake procedure to place the payload into a low Mars parking orbit. The payload delivery times range from 160 days to 873 days (2.39 years).

  1. Integrated residential photovoltaic array development

    NASA Technical Reports Server (NTRS)

    Shepard, N. F., Jr.

    1981-01-01

    An advanced, universally-mountable, integrated residential photovoltaic array concept was defined based upon an in-depth formulation and evaluation of three candidate approaches which were synthesized from existing or proposed residential array concepts. The impact of module circuitry and process sequence is considered and technology gaps and performance drivers associated with residential photovoltaic array concepts are identified. The actual learning experience gained from the comparison of the problem areas of the hexagonal shingle design with the rectangular module design led to what is considered an advanced array concept. Building the laboratory mockup provided actual experience and the opportunity to uncover additional technology gaps.

  2. [Advances in microbial solar cells--A review].

    PubMed

    Guo, Xiaoyun; Yu, Changping; Zheng, Tianling

    2015-08-04

    The energy crisis has become one of the major problems hindering the development of the world. The emergence of microbial fuel cells provides a new solution to the energy crisis. Microbial solar cells, integrating photosynthetic organisms such as plants and microalgae into microbial fuel cells, can convert solar energy into electrical energy. Microbial solar cell has steady electric energy, and broad application prospects in wastewater treatment, biodiesel processing and intermediate metabolites production. Here we reviewed recent progress of microbial solar cells from the perspective of the role of photosynthetic organisms in microbial fuel cells, based on a vast amount of literature, and discussed their advantages and deficiency. At last, brief analysis of the facing problems and research needs of microbial fuel cells are undertaken. This work was expected to be beneficial for the application of the microbial solar cells technology.

  3. Solar Water Heater

    NASA Technical Reports Server (NTRS)

    1993-01-01

    As a Jet Propulsion Laboratory (JPL) scientist Dr. Eldon Haines studied the solar energy source and solar water heating. He concluded he could build a superior solar water heating system using the geyser pumping principle. He resigned from JPL to develop his system and later form Sage Advance Corporation to market the technology. Haines' Copper Cricket residential system has no moving parts, is immune to freeze damage, needs no roof-mounted tanks, and features low maintenance. It provides 50-90 percent of average hot water requirements. A larger system, the Copper Dragon, has been developed for commercial installations.

  4. No Photon Left Behind: Advanced Optics at ARPA-E for Buildings and Solar Energy

    NASA Astrophysics Data System (ADS)

    Branz, Howard M.

    2015-04-01

    Key technology challenges in building efficiency and solar energy utilization require transformational optics, plasmonics and photonics technologies. We describe advanced optical technologies funded by the Advanced Research Projects Agency - Energy. Buildings technologies include a passive daytime photonic cooler, infra-red computer vision mapping for energy audit, and dual-band electrochromic windows based on plasmonic absorption. Solar technologies include novel hybrid energy converters that combine high-efficiency photovoltaics with concentrating solar thermal collection and storage. Because the marginal cost of thermal energy storage is low, these systems enable generation of inexpensive and dispatchable solar energy that can be deployed when the sun doesn't shine. The solar technologies under development include nanoparticle plasmonic spectrum splitting, Rugate filter interference structures and photovoltaic cells that can operate efficiently at over 400° C.

  5. Applicability of advanced automotive heat engines to solar thermal power

    NASA Technical Reports Server (NTRS)

    Beremand, D. G.; Evans, D. G.; Alger, D. L.

    1981-01-01

    The requirements of a solar thermal power system are reviewed and compared with the predicted characteristics of automobile engines under development. A good match is found in terms of power level and efficiency when the automobile engines, designed for maximum powers of 65-100 kW (87 to 133 hp) are operated to the nominal 20-40 kW electric output requirement of the solar thermal application. At these reduced power levels it appears that the automotive gas turbine and Stirling engines have the potential to deliver the 40+ percent efficiency goal of the solar thermal program.

  6. Conceptual definition of a technology development mission for advanced solar dynamic power systems

    NASA Technical Reports Server (NTRS)

    Migra, R. P.

    1986-01-01

    An initial conceptual definition of a technology development mission for advanced solar dynamic power systems is provided, utilizing a space station to provide a dedicated test facility. The advanced power systems considered included Brayton, Stirling, and liquid metal Rankine systems operating in the temperature range of 1040 to 1400 K. The critical technologies for advanced systems were identified by reviewing the current state of the art of solar dynamic power systems. The experimental requirements were determined by planning a system test of a 20 kWe solar dynamic power system on the space station test facility. These requirements were documented via the Mission Requirements Working Group (MRWG) and Technology Development Advocacy Group (TDAG) forms. Various concepts or considerations of advanced concepts are discussed. A preliminary evolutionary plan for this technology development mission was prepared.

  7. An advanced concentrator for solar dynamic power systems in space

    NASA Technical Reports Server (NTRS)

    Beninga, Kelly; Davenport, Roger

    1989-01-01

    Solar concentrators based on rigidized stretched-membrane technology, which have been shown to be a possible alternative to rigid segmented concentrators for solar dynamic power applications in space, are discussed. Membrane concentrators offer an advantage in weight, efficiency of structure use, deployability, and cost. Predeployment packaging and subsequent deployment of a prototype membrane concentrator has been demonstrated. Attractive membrane fabrication techniques have been identified and demonstrated. The concept is described, and materials selection and membrane fabrication are examined.

  8. Advanced and In Situ Analytical Methods for Solar Fuel Materials.

    PubMed

    Chan, Candace K; Tüysüz, Harun; Braun, Artur; Ranjan, Chinmoy; La Mantia, Fabio; Miller, Benjamin K; Zhang, Liuxian; Crozier, Peter A; Haber, Joel A; Gregoire, John M; Park, Hyun S; Batchellor, Adam S; Trotochaud, Lena; Boettcher, Shannon W

    2016-01-01

    In situ and operando techniques can play important roles in the development of better performing photoelectrodes, photocatalysts, and electrocatalysts by helping to elucidate crucial intermediates and mechanistic steps. The development of high throughput screening methods has also accelerated the evaluation of relevant photoelectrochemical and electrochemical properties for new solar fuel materials. In this chapter, several in situ and high throughput characterization tools are discussed in detail along with their impact on our understanding of solar fuel materials.

  9. Toward a National Plan for the Accelerated Commercialization of Solar Energy: residential/commercial buildings market sector workbook

    SciTech Connect

    Taul, Jr., J. W.; de Jong, D. L.

    1980-01-01

    This workbook contains preliminary data and assumptions used during the preparation of inputs to a National Plan for the Accelerated Commercialization of Solar Energy (NPAC). The workbook indicates the market potential, competitive position, market penetration, and technological characteristics of solar technologies for this market sector over the next twenty years. The workbook also presents projections of the mix of solar technologies by US Census Regions. In some cases, data have been aggregated to the national level. Emphasis of the workbook is on a mid-price fuel scenario, Option II, that meets about a 20% solar goal by the year 2000. The energy demand for the mid-price scenario is projected at 115 quads in the year 2000. The workbook, prepared in April 1979, represents government policies and programs anticipated at that time.

  10. Advanced solar-propelled cargo spacecraft for Mars missions

    NASA Technical Reports Server (NTRS)

    Auziasdeturenne, J.; Beall, M.; Burianek, J.; Cinniger, A.; Dunmire, B.; Haberman, E.; Iwamoto, J.; Johnson, S.; Mccracken, S.; Miller, M.

    1989-01-01

    At the University of Washington, three concepts for an unmanned, solar powered, cargo spacecraft for Mars-support missions have been investigated. These spacecraft are designed to carry a 50,000 kg payload from a low Earth orbit to a low Mars orbit. Each design uses a distinctly different propulsion system: a solar radiation absorption (SRA) system, a solar-pumped laser (SPL) system, and a solar powered mangetoplasmadynamic (MPD) arc system. The SRA directly converts solar energy to thermal energy in the propellant through a novel process developed at the University of Washington. A solar concentrator focuses sunlight into an absorption chamber. A mixture of hydrogen and potassium vapor absorbs the incident radiation and is heated to approximately 3700 K. The hot propellant gas exhausts through a nozzle to produce thrust. The SRA has an I(sub sp) of approximately 1000 sec and produces a thrust of 2940 N using two thrust chambers. In the SPL system, a pair of solar-pumped, multi-megawatt, CO2 lasers in sun-synchronous Earth orbit converts solar energy to laser energy. The laser beams are transmitted to the spacecraft via laser relay satellites. The laser energy heats the hydrogen propellant through a plasma breakdown process in the center of an absorption chamber. Propellant flowing through the chamber, heated by the plasma core, expands through a nozzle to produce thrust. The SPL has an I(sub sp) of 1285 sec and produces a thrust of 1200 N using two thrust chambers. The MPD system uses indium phosphide solar cells to convert sunlight to electricity, which powers the propulsion system. In this system, the argon propellant is ionized and electromagnetically accelerated by a magnetoplasmadynamic arc to produce thrust. The MPD spacecraft has an I(sub sp) of 2490 sec and produces a thrust of 100 N. Various orbital transfer options are examined for these concepts. In the SRA system, the mother ship transfers the payload into a very high Earth orbit and a small auxiliary

  11. Mission analysis and performance comparison for an Advanced Solar Photon Thruster

    NASA Astrophysics Data System (ADS)

    Dachwald, Bernd; Wurm, Patrick

    2011-12-01

    The so-called "compound solar sail", also known as "Solar Photon Thruster" (SPT), is a design concept, for which the two basic functions of the solar sail, namely light collection and thrust direction, are uncoupled. In this paper, we introduce a novel SPT concept, termed the Advanced Solar Photon Thruster (ASPT), which does not suffer from the simplified assumptions that have been made for the analysis of compound solar sails in previous studies. After having presented the equations that describe the force on the ASPT and after having performed a detailed design analysis, the performance of the ASPT with respect to the conventional flat solar sail (FSS) is investigated for three interplanetary mission scenarios: an Earth-Venus rendezvous, where the solar sail has to spiral towards the Sun, an Earth-Mars rendezvous, where the solar sail has to spiral away from the Sun, and an Earth-NEA rendezvous (to near-Earth asteroid 1996FG3), where a large change in orbital eccentricity is required. The investigated solar sails have realistic near-term characteristic accelerations between 0.1 and 0.2 mm/s 2. Our results show that an SPT is not superior to the flat solar sail unless very idealistic assumptions are made.

  12. NASA advanced aeronautics design solar powered remotely piloted vehicle

    NASA Technical Reports Server (NTRS)

    Elario, David S.; Guillmette, Neal H.; Lind, Gregory S.; Webster, Jonathan D.; Ferreira, Michael J.; Konstantakis, George C.; Marshall, David L.; Windt, Cari L.

    1991-01-01

    Environmental problems such as the depletion of the ozone layer and air pollution demand a change in traditional means of propulsion that is sensitive to the ecology. Solar powered propulsion is a favorable alternative that is both ecologically harmless as well as cost effective. Integration of solar energy into designs ranging from futuristic vehicles to heating is beneficial to society. The design and construction of a Multi-Purpose Remotely Piloted Vehicle (MPRPV) seeks to verify the feasibility of utilizing solar propulsion as a primary fuel source. This task has been a year long effort by a group of ten students, divided into five teams, each dealing with different aspects of the design. The aircraft was designed to take-off, climb to the design altitude, fly in a sustained figure-eight flight path, and cruise for approximately one hour. This mission requires flight at Reynolds numbers between 150,000 and 200,000 and demands special considerations in the aerodynamic design in order to achieve flight in this regime. Optimal performance requires a light weight configuration with both structural integrity and maximum power availability. The structure design and choice of solar cells for the propulsion was governed by the weight, efficiency, and cost considerations. The final design is a MPRPV weighting 35 N which cruises 7 m/s at the design altitude of 50 m. The configuration includes a wing composed of balsa and foam NACA 6409 airfoil sections and carbon fiber spars, a tail of similar construction, and a truss structure fuselage. The propulsion system consists of 98 10 percent efficient solar cells donated by Mobil Solar, a NiCad battery for energy storage, and a folding propeller regulated by a lightweight and efficient control system. The airfoils and propeller chosen for the design were research and tested during the design process.

  13. Advanced Thin Film Solar Arrays for Space: The Terrestrial Legacy

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila; Hepp, Aloysius; Raffaelle, Ryne; Flood, Dennis

    2001-01-01

    As in the case for single crystal solar cells, the first serious thin film solar cells were developed for space applications with the promise of better power to weight ratios and lower cost. Future science, military, and commercial space missions are incredibly diverse. Military and commercial missions encompass both hundreds of kilowatt arrays to tens of watt arrays in various earth orbits. While science missions also have small to very large power needs there are additional unique requirements to provide power for near sun missions and planetary exploration including orbiters, landers, and rovers both to the inner planets and the outer planets with a major emphasis in the near term on Mars. High power missions are particularly attractive for thin film utilization. These missions are generally those involving solar electric propulsion, surface power systems to sustain an outpost or a permanent colony on the surface of the Moon or Mars, space based lasers or radar, or large Earth orbiting power stations which can serve as central utilities for other orbiting spacecraft, or potentially beaming power to the Earth itself. This paper will discuss the current state of the art of thin film solar cells and the synergy with terrestrial thin film photovoltaic evolution. It will also address some of the technology development issues required to make thin film photovoltaics a viable choice for future space power systems.

  14. Newman Unit 1 advanced solar repowering. Final report

    SciTech Connect

    1982-04-01

    The five appendices give the selection process and system specification of the Newman Unit 1 solar repowering system, including the conceptual design drawings and diagrams; input data for the simulation program; and a review of the most important characteristics of the existing plant. (LEW)

  15. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Klaus, Kurt K.; Elsperman, M. S.; Rogers, F.

    2013-10-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  16. Mission Concepts Enabled by Solar Electric Propulsion and Advanced Modular Power Systems

    NASA Astrophysics Data System (ADS)

    Elsperman, M. S.; Klaus, K.; Rogers, F.

    2013-12-01

    Introduction: Over the last several years we have introduced a number of planetary mission concepts enabled by Solar Electric Propulsion and Advanced Modular Power systems. The Boeing 702 SP: Using a common spacecraft for multiple missions reduces costs. Solar electric propulsion (SEP) provides the flexibility required for multiple mission objectives. Hosted payloads allow launch and operations costs to be shared. Advanced Modular Power System (AMPS): The 702 SP for deep space is designed to be able to use the Advanced Modular Power System (AMPS) solar array, producing multi Kw power levels with significantly lower system mass than current solar power system technologies. Mission Concepts: Outer Planets. 1) Europa Explorer - Our studies demonstrate that New Frontiers-class science missions to the Jupiter and Saturn systems are possible with commercial solar powered spacecraft. 2) Trojan Tour -The mission objective is 1143 Odysseus, consistent with the Decadal Survey REP (Radioisotope Electric Propulsion) mission objective. Small Body. 1) NEO Precursor Mission - NEO missions benefit greatly by using high ISP (Specific Impulse) Solar Electric Propulsion (SEP) coupled with high power generation systems. This concept further sets the stage for human exploration by doing the type of science exploration needed and flight demonstrating technology advances (high power generation, SEP). 2) Multiple NEO Rendezvous, Reconnaissance and In Situ Exploration - We propose a two spacecraft mission (Mother Ship and Small Body Lander) rendezvous with multiple Near Earth Objects (NEO). Mars. Our concept involved using the Boeing 702SP with a highly capable SAR imager that also conducts autonomous rendezvous and docking experiments accomplished from Mars orbit. Conclusion: Using advanced in-space power and propulsion technologies like High Power Solar Electric Propulsion provides enormous mission flexibility to execute baseline science missions and conduct Technology Demonstrations in

  17. Quantum-Dot-Based Solar Cells: Recent Advances, Strategies, and Challenges.

    PubMed

    Kim, Mee Rahn; Ma, Dongling

    2015-01-02

    Among next-generation photovoltaic systems requiring low cost and high efficiency, quantum dot (QD)-based solar cells stand out as a very promising candidate because of the unique and versatile characteristics of QDs. The past decade has already seen rapid conceptual and technological advances on various aspects of QD solar cells, and diverse opportunities, which QDs can offer, predict that there is still ample room for further development and breakthroughs. In this Perspective, we first review the attractive advantages of QDs, such as size-tunable band gaps and multiple exciton generation (MEG), beneficial to solar cell applications. We then analyze major strategies, which have been extensively explored and have largely contributed to the most recent and significant achievements in QD solar cells. Finally, their high potential and challenges are discussed. In particular, QD solar cells are considered to hold immense potential to overcome the theoretical efficiency limit of 31% for single-junction cells.

  18. Advanced glazing and associated materials for solar and building applications: International Energy Agency Solar Heating and Cooling Program Task 18

    NASA Astrophysics Data System (ADS)

    Hutchins, Michael G.

    1992-11-01

    Following a program definition phase of 2 years, Task 18 of the International Energy Agency Solar Heating & Cooling program commenced a 5 year research phase in April 1992. Task 18 investigates a wide range of advanced glazing materials and glazing systems which include monolithic and granular aerogels, transparent insulation materials, chromogenic materials, evacuated glazings, low-emittance coatings, solar collector covers, angular selective transmittance thin films, holographic and light guide materials, and frame and edge seal technology. In addition to materials-centered research, Task 18 concentrates on measurement of key glazing properties such as total energy transmittance, U-value, and spectral directional optical properties, and through the use of building energy analysis software tools the identification of appropriate applications, control strategies, and energy and environmental benefits to be derived from advanced glazing products. Fifteen OECD countries are participating in Task 18 which is led by the United Kingdom.

  19. Photovoltaic Residential Applications Program Implementation Workshop Proceedings

    NASA Technical Reports Server (NTRS)

    Barbieri, R. H.

    1980-01-01

    Two major aspects of the workshop are presented: (1) presentations on the Photovoltaic program and the National Solar Heating and Cooling Demonstration program, and (2) discussions on the issues pertinent to the Residential Application program.

  20. High performance silicon solar arrays employing advanced structures

    NASA Technical Reports Server (NTRS)

    Rockey, D. E.; Hedgepeth, J. M.; Adams, L.

    1981-01-01

    Specific design features to reduce cell mass, lower panel operating temperatures, and improve power to mass ratios for silicon solar cell arrays in space applications are presented. Because mass constraints limit payload capacity for launch into GEO, graphite/epoxy structures combined with high performance Si cells are needed to deliver a power/mass ratio of 265 W/kg, notably for Solar Electric Propulsion systems, compared with existing level of 65 W/kg. Shallow diffusion and back surface field cell technology have raised cell efficiencies to 15%, with a back emissivity of 1.64. Structural design requirements comprise Shuttle interface compatibility, full ground test capability, low mass, and high stiffness. Three array alternatives are discussed, and the STACBEAM configuration, which consists of a triangular truss and a piston deployer with folding accomplished on simple hinges, provides 0.2 Hz stiffness and achieves the design power/mass goals.

  1. Recent advances in thin film CdTe solar cells

    SciTech Connect

    Ferekides, C.S.; Ceekala, V.; Dugan, K.; Killian, L.; Oman, D.; Swaminathan, R.; Morel, D.

    1996-01-01

    CdTe thin film solar cells have been fabricated on a variety of glass substrates (borosilicate and soda lime). The CdS films were deposited to a thickness of 500{endash}2000 A by the chemical bath deposition (CBD), rf sputtering, or close spaced sublimation (CSS) processes. The CdTe films were deposited by CSS in the temperature range of 450{endash}625{degree}C. The main objective of this work is to fabricate high efficiency solar cells using processes that can meet low cost manufacturing requirements. In an attempt to enhance the blue response of the CdTe cells, ZnS films have also been prepared (CBD, rf sputtering, CSS) as an alternative window layer to CdS. Device behavior has been found to be consistent with a recombination model. {copyright} {ital 1996 American Institute of Physics.}

  2. Advances in simulation study on organic small molecular solar cells

    NASA Astrophysics Data System (ADS)

    Zhang, Xuan; Guo, Wenge; Li, Ming; Ma, Wentao; Meng, Sen

    2015-02-01

    Recently, more focuses have been put on organic semiconductors because of its advantages, such as its flexibility, ease of fabrication and potential low cost, etc. The reasons we pay highlight on small molecular photovoltaic material are its ease of purification, easy to adjust and determine structure, easy to assemble range units and get high carrier mobility, etc. Simulation study on organic small molecular solar cells before the experiment can help the researchers find relationship between the efficiency and structure parameters, properties of material, estimate the performance of the device, bring the optimization of guidance. Also, the applicability of the model used in simulation can be discussed by comparison with experimental data. This paper summaries principle, structure, progress of numerical simulation on organic small molecular solar cells.

  3. Advanced Antireflection Coatings for High-Performance Solar Energy Applications

    NASA Technical Reports Server (NTRS)

    Pan, Noren

    2015-01-01

    Phase II objectives: Develop and refine antireflection coatings incorporating lanthanum titanate as an intermediate refractive index material; Investigate wet/dry thermal oxidation of aluminum containing semiconductor compounds as a means of forming a more transparent window layer with equal or better optical properties than its unoxidized form; Develop a fabrication process that allows integration of the oxidized window layer and maintains the necessary electrical properties for contacting the solar cell; Conduct an experimental demonstration of the best candidates for improved antireflection coatings.

  4. The Performance of Advanced III-V Solar Cells

    NASA Technical Reports Server (NTRS)

    Mueller, Robert L.; Gaddy, Edward; Day, John H. (Technical Monitor)

    2002-01-01

    Test results show triple junction solar cells with efficiencies as high as 27% at 28C and 136.7 mw/sq cm. Triple junction cells also achieve up to 27.5% at -120 C and 5 mw/sq cm, conditions applicable to missions to Jupiter. Some triple junction cells show practically no degradation as a result of Low Intensity Low Temperature (LILT) effects, while others show some; this degradation can be overcome with minor changes to the cell design.

  5. From first generation biofuels to advanced solar biofuels.

    PubMed

    Aro, Eva-Mari

    2016-01-01

    Roadmaps towards sustainable bioeconomy, including the production of biofuels, in many EU countries mostly rely on biomass use. However, although biomass is renewable, the efficiency of biomass production is too low to be able to fully replace the fossil fuels. The use of land for fuel production also introduces ethical problems in increasing the food price. Harvesting solar energy by the photosynthetic machinery of plants and autotrophic microorganisms is the basis for all biomass production. This paper describes current challenges and possibilities to sustainably increase the biomass production and highlights future technologies to further enhance biofuel production directly from sunlight. The biggest scientific breakthroughs are expected to rely on a new technology called "synthetic biology", which makes engineering of biological systems possible. It will enable direct conversion of solar energy to a fuel from inexhaustible raw materials: sun light, water and CO2. In the future, such solar biofuels are expected to be produced in engineered photosynthetic microorganisms or in completely synthetic living factories.

  6. Development of advanced silicon solar cells for Space Station Freedom

    NASA Technical Reports Server (NTRS)

    Lillington, David R.

    1990-01-01

    This report describes the development of large area high efficiency wrapthrough solar cells for Space Station Freedom. The goal of this contract was the development and fabrication of 8 x 8 cm coplanar back contact solar cells with a minimum output of 1.039 watts/cell. The first task in this program was a modeling study to determine the optimum configuration of the cell and to study the effects of surface passivation, substrate resistivity, and back surface field on the BOL and EOL performance. In addition, the optical stack, including the cell cover, AR coatings, and Kapton blanket, was modeled to optimize 'on orbit' operation. The second phase was a manufacturing development phase to develop high volume manufacturing processes for the reliable production of low recombination velocity boron back surface fields, techniques to produce smooth, low leakage wrapthrough holes, passivation, photoresist application methods, and metallization schemes. The final portion of this program was a pilot production phase. Seven hundred solar cells were delivered in this phase. At the end of the program, cells with average efficiencies over 13 percent were being produced with power output in excess of 1.139 watts/cell, thus substantially exceeding the program goal.

  7. Advances in Concentrating Solar Power Collectors: Mirrors and Solar Selective Coatings

    SciTech Connect

    Kenendy, C. E.

    2007-10-10

    The intention is to explore the feasibility of depositing the coating by lower-cost methods and to perform a rigorous cost analysis after a viable high-temperature solar-selective coating is demonstrated by e-beam.

  8. Residential Wiring.

    ERIC Educational Resources Information Center

    Taylor, Mark

    The second in a series of three curriculum packages on wiring, these materials for a five-unit course were developed to prepare postsecondary students for entry-level employment in the residential wiring trade. The five units are: (1) blueprint reading and load calculations; (2) rough-in; (3) service; (4) trim out and troubleshooting; and (5) load…

  9. Advances in Radiation-Tolerant Solar Arrays for SEP Missions

    NASA Technical Reports Server (NTRS)

    O'Neill, Mark J.; Eskenazi, Michael I.; Ferguson, Dale C.

    2007-01-01

    As the power levels of commercial communications satellites reach the 20 kWe and higher, new options begin to emerge for transferring the satellite from LEO to GEO. In the past electric propulsion has been demonstrated successfully for this mission - albeit under unfortunate circumstances when the kick motor failed. The unexpected use of propellant for the electric propulsion (EP) system compromised the life of that vehicle, but did demonstrate the viability of such an approach. Replacing the kick motor on a satellite and replacing that mass by additional propellant for the EP system as well as mass for additional revenue-producing transponders should lead to major benefits for the provider. Of course this approach requires that the loss in solar array power during transit of the Van Allen radiation belts is not excessive and still enables the 15 to 20 year mission life. In addition, SEP missions to Jupiter, with its exceptional radiation belts, would mandate a radiation-resistant solar array to compete with a radioisotope alternative. Several critical issues emerge as potential barriers to this approach: reducing solar array radiation damage, operating the array at high voltage (>300 V) for extended times for Hall or ion thrusters, designing an array that will be resistant to micrometeoroid impacts and the differing environmental conditions as the vehicle travels from LEO to GEO (or at Jupiter), producing an array that is light weight to preserve payload mass fraction - and to do this at a cost that is lower than today's arrays. This paper will describe progress made to date on achieving an array that meets all these requirements and is also useful for deep space electric propulsion missions.

  10. Advanced solar thermal storage medium test data and analysis

    NASA Technical Reports Server (NTRS)

    Saha, H.

    1981-01-01

    A comparative study has been made of experimentally obtained heat transfer and heat storage characteristics of a solar thermal energy storage bed utilizing containerized water or phase change material (PCM) and rock or brick. It is shown that (1) containers with an L/D ratio of 0.80 and a mass/surface area ratio of 2.74 in a random stacking arrangement have the optimum heat transfer characteristics; and (2) vertical stacking has the least pressure drop across the test bed. It is also found that standard bricks with appropriate holes make an excellent storage medium.

  11. Compatibility of molten salts with advanced solar dynamic receiver materials

    NASA Technical Reports Server (NTRS)

    Jaworske, D. A.; Perry, W. D.

    1989-01-01

    Metal-coated graphite fibers are being considered as a thermal conductivity enhancement filler material for molten salts in solar dynamic thermal energy storage systems. The successful metal coating chosen for this application must exhibit acceptable wettability and must be compatible with the molten salt environment. Contact angle values between molten lithium fluoride and several metal, metal fluoride, and metal oxide substrates have been determined at 892 C using a modification of the Wilhelmy plate technique. Reproducible contact angles with repeated exposure to the molten LiF indicated compatibility.

  12. Thermal evaluation of advanced solar dynamic heat receiver performance

    NASA Technical Reports Server (NTRS)

    Crane, Roger A.

    1989-01-01

    The thermal performance of a variety of concepts for thermal energy storage as applied to solar dynamic applications is discussed. It is recognized that designs providing large thermal gradients or large temperature swings during orbit are susceptible to early mechanical failure. Concepts incorporating heat pipe technology may encounter operational limitations over sufficiently large ranges. By reviewing the thermal performance of basic designs, the relative merits of the basic concepts are compared. In addition the effect of thermal enhancement and metal utilization as applied to each design provides a partial characterization of the performance improvements to be achieved by developing these technologies.

  13. Extending the Endurance of Small Unmanned Aerial Vehicles Using Advanced Flexible Solar Cells

    DTIC Science & Technology

    2012-12-01

    construction (from [40]). ...............................................37 Figure 31. Energy density comparison including Li- S (from [43...discharging, respective- ly, without the use of circuitry [43]. Figure 31. Energy density comparison including Li- S (from [43]). 40 While the sulfur...USING ADVANCED FLEXIBLE SOLAR CELLS 5. FUNDING NUMBERS 6. AUTHOR( S ) Christopher R. Gromadski 7. PERFORMING ORGANIZATION NAME( S ) AND ADDRESS(ES

  14. Greening the Grid - Advancing Solar, Wind, and Smart Grid Technologies (Spanish Version)

    SciTech Connect

    2016-04-01

    This is the Spanish version of 'Greening the Grid - Advancing Solar, Wind, and Smart Grid Technologies'. Greening the Grid provides technical assistance to energy system planners, regulators, and grid operators to overcome challenges associated with integrating variable renewable energy into the grid.

  15. NREL's Education Program in Action in the Concentrating Solar Power Program Advanced Materials Task

    NASA Astrophysics Data System (ADS)

    Kennedy, Cheryl

    2010-03-01

    Concentrating solar power (CSP) technologies use large mirrors to concentrate sunlight and the thermal energy collected is converted to electricity. The CSP industry is growing rapidly and is expected to reach 25 GW globally by 2020. Cost target goals are for CSP technologies to produce electricity competitive with intermediate-load power generation (i.e., natural gas) by 2015 with 6 hours of thermal storage and competitive in carbon constrained base load power markets (i.e., coal) by 2020 with 12-17 hours of thermal storage. The solar field contributes more than 40% of the total cost of a parabolic trough plant and together the mirrors and receivers contribute more than 25% of the installed solar field cost. CSP systems cannot hit these targets without aggressive cost reductions and revolutionary performance improvements from technology advances. NREL's Advanced Materials task in the CSP Advanced R&D project performs research to develop low cost, high performance, durable solar reflector and high-temperature receiver materials to meet these needs. The Advanced Materials task leads the world in this research and the task's reliance on NREL's educational program will be discussed.

  16. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis was conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  17. Advanced sensible heat solar receiver for space power

    NASA Technical Reports Server (NTRS)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

    NASA Lewis, through in-house efforts, has begun a study to generate a conceptual design of a sensible heat solar receiver and to determine the feasibility of such a system for space power applications. The sensible heat solar receiver generated in this study uses pure lithium as the thermal storage medium and was designed for a 7 kWe Brayton (PCS) operating at 1100 K. The receiver consists of two stages interconnected via temperature sensing variable conductance sodium heat pipes. The lithium is contained within a niobium vessel and the outer shell of the receiver is constructed of third generation rigid, fibrous ceramic insulation material. Reradiation losses are controlled with niobium and aluminum shields. By nature of design, the sensible heat receiver generated in this study is comparable in both size and mass to a latent heat system of similar thermal capacitance. The heat receiver design and thermal analysis were conducted through the combined use of PATRAN, SINDA, TRASYS, and NASTRAN software packages.

  18. The dynamic solar chromosphere: recent advances from high resolution telescopes

    NASA Astrophysics Data System (ADS)

    Tziotziou, Konstantinos; Tsiropoula, Georgia

    This review focuses on the solar chromosphere, a very inhomogeneous and dynamic layer that exhibits phenomena on a large range of spatial and temporal scales. High-resolution observa-tions from existing telescopes (DST, SST, DOT), as well as long-duration observations with Hinode's SOT employing lines such as the Ca II infrared lines, the Ca II HK and above all the Hα line reveal an incredibly rich, dynamic and highly structured environment, both in quiet and active regions. The fine-structure chromosphere, is mainly constituted by fibrilar features that connect various parts of active regions or span across network cell interiors. We discuss this highly dynamical solar chromosphere, especially below the magnetic canopy, which is gov-erned by flows reflecting both the complex geometry and dynamics of the magnetic field and the propagation and dissipation of waves in the different atmospheric layers. A comprehensive view of the fine-structure chromosphere requires deep understanding of the physical processes involved, investigation of the intricate link with structures/processes at lower photospheric lev-els and analysis of its impact on the mass and energy transport to higher atmospheric layers through flows resulting from different physical processes such as magnetic reconnection and waves. Furthermore, we assess the challenges facing theory and numerical modelling which require the inclusion of several physical ingredients, such as non-LTE and three-dimensional numerical simulations.

  19. Advanced Solar Cell and Array Technology for NASA Deep Space Missions

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael; Benson, Scott; Scheiman, David; Finacannon, Homer; Oleson, Steve; Landis, Geoffrey

    2008-01-01

    A recent study by the NASA Glenn Research Center assessed the feasibility of using photovoltaics (PV) to power spacecraft for outer planetary, deep space missions. While the majority of spacecraft have relied on photovoltaics for primary power, the drastic reduction in solar intensity as the spacecraft moves farther from the sun has either limited the power available (severely curtailing scientific operations) or necessitated the use of nuclear systems. A desire by NASA and the scientific community to explore various bodies in the outer solar system and conduct "long-term" operations using using smaller, "lower-cost" spacecraft has renewed interest in exploring the feasibility of using photovoltaics for to Jupiter, Saturn and beyond. With recent advances in solar cell performance and continuing development in lightweight, high power solar array technology, the study determined that photovoltaics is indeed a viable option for many of these missions.

  20. Recent advancements in low cost solar cell processing

    NASA Technical Reports Server (NTRS)

    Ralph, E. L.

    1975-01-01

    A proof-of-concept solar cell process has been developed that is adaptable to automation. This involved the development of a new contact system, a new antireflection coating system, a drift field cell design and a new contoured surface treatment. All these processes are performed without the use of vacuum chambers and expensive masking techniques, thus providing the possibility of reduced costs by automation using conventional semiconductor processing machinery. The contacts were printed on the cells by conventional silk screen machinery. The P(+) back field was formed by diffusing in aluminum from a printed aluminum back contact. The antireflection coating was formed by spinning on and baking a TiO2-SiO2 glass film. Air-mass-zero efficiencies of over 10% were achieved using this completely vacuum-free process.

  1. Effect of Fuel Wobbe Number on Pollutant Emissions from Advanced Technology Residential Water Heaters: Results of Controlled Experiments

    SciTech Connect

    Rapp, Vi H.; Singer, Brett C.

    2014-03-01

    The research summarized in this report is part of a larger effort to evaluate the potential air quality impacts of using liquefied natural gas in California. A difference of potential importance between many liquefied natural gas blends and the natural gas blends that have been distributed in California in recent years is the higher Wobbe number of liquefied natural gas. Wobbe number is a measure of the energy delivery rate for appliances that use orifice- or pressure-based fuel metering. The effect of Wobbe number on pollutant emissions from residential water heaters was evaluated in controlled experiments. Experiments were conducted on eight storage water heaters, including five with “ultra low-NO{sub X}” burners, and four on-demand (tankless) water heaters, all of which featured ultra low-NO{sub X} burners. Pollutant emissions were quantified as air-free concentrations in the appliance flue and fuel-based emission factors in units of nanogram of pollutant emitter per joule of fuel energy consumed. Emissions were measured for carbon monoxide (CO), nitrogen oxides (NO{sub X}), nitrogen oxide (NO), formaldehyde and acetaldehyde as the water heaters were operated through defined operating cycles using fuels with varying Wobbe number. The reference fuel was Northern California line gas with Wobbe number ranging from 1344 to 1365. Test fuels had Wobbe numbers of 1360, 1390 and 1420. The most prominent finding was an increase in NO{sub X} emissions with increasing Wobbe number: all five of the ultra low-NO{sub X} storage water heaters and two of the four ultra low-NO{sub X} on-demand water heaters had statistically discernible (p<0.10) increases in NO{sub X} with fuel Wobbe number. The largest percentage increases occurred for the ultra low-NO{sub X} water heaters. There was a discernible change in CO emissions with Wobbe number for all four of the on-demand devices tested. The on-demand water heater with the highest CO emissions also had the largest CO increase

  2. Tool for Generating Realistic Residential Hot Water Event Schedules: Preprint

    SciTech Connect

    Hendron, B.; Burch, J.; Barker, G.

    2010-08-01

    The installed energy savings for advanced residential hot water systems can depend greatly on detailed occupant use patterns. Quantifying these patterns is essential for analyzing measures such as tankless water heaters, solar hot water systems with demand-side heat exchangers, distribution system improvements, and recirculation loops. This paper describes the development of an advanced spreadsheet tool that can generate a series of year-long hot water event schedules consistent with realistic probability distributions of start time, duration and flow rate variability, clustering, fixture assignment, vacation periods, and seasonality. This paper also presents the application of the hot water event schedules in the context of an integral-collector-storage solar water heating system in a moderate climate.

  3. Adaptive optics real time processing design for the advanced technology solar telescope

    NASA Astrophysics Data System (ADS)

    Richards, Kit

    2012-07-01

    The four meter Advanced Technology Solar Telescope (ATST) adaptive optics (AO) system will require at least twenty-four times the real time processing power as the Dunn Solar Telescope AO system. An FPGA solution for ATST AO real time processing is being pursued instead of the parallel DSP approach used for the Dunn AO76 system. An analysis shows FPGAs will have lower latency and lower hardware cost than an equivalent DSP solution. Interfacing to the proposed high speed camera and the deformable mirror will be simpler and have lower latency than with DSPs. This paper will discuss the current design and progress toward implementing the FPGA solution.

  4. Development of processing procedures for advanced silicon solar cells. [antireflection coatings and short circuit currents

    NASA Technical Reports Server (NTRS)

    Scott-Monck, J. A.; Stella, P. M.; Avery, J. E.

    1975-01-01

    Ten ohm-cm silicon solar cells, 0.2 mm thick, were produced with short circuit current efficiencies up to thirteen percent and using a combination of recent technical advances. The cells were fabricated in conventional and wraparound contact configurations. Improvement in cell collection efficiency from both the short and long wavelengths region of the solar spectrum was obtained by coupling a shallow junction and an optically transparent antireflection coating with back surface field technology. Both boron diffusion and aluminum alloying techniques were evaluated for forming back surface field cells. The latter method is less complicated and is compatible with wraparound cell processing.

  5. Advances in thin-film solar cells for lightweight space photovoltaic power

    SciTech Connect

    Landis, G.A.; Bailey, S.G.; Flood, D.J.

    1989-01-01

    The present stature and current research directions of photovoltaic arrays as primary power systems for space are reviewed. There have recently been great advances in the technology of thin-film solar cells for terrestrial applications. In a thin-film solar cell the thickness of the active element is only a few microns; transfer of this technology to space arrays could result in ultralow-weight solar arrays with potentially large gains in specific power. Recent advances in thin-film solar cells are reviewed, including polycrystalline copper-indium selenide (CuInSe2) and related I-III-VI2 compounds, polycrystalline cadmium telluride and related II-VI compounds, and amorphous silicon:hydrogen and alloys. The best experimental efficiency on thin-film solar cells to date is 12 percent AMO for CuInSe2. This efficiency is likely to be increased in the next few years. The radiation tolerance of thin-film materials is far greater than that of single-crystal materials. CuInSe2 shows no degradation when exposed to 1 MeV electrons. Experimental evidence also suggests that most of all of the radiation damage on thin-films can be removed by a low temperature anneal. The possibility of thin-film multibandgap cascade solar cells is discussed, including the tradeoffs between monolithic and mechanically stacked cells. The best current efficiency for a cascade is 12.5 percent AMO for an amorphous silicon on CuInSe2 multibandgap combination. Higher efficiencies are expected in the future. For several missions, including solar-electric propulsion, a manned Mars mission, and lunar exploration and manufacturing, thin-film photovolatic arrays may be a mission-enabling technology.

  6. Advances in thin-film solar cells for lightweight space photovoltaic power

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila G.; Flood, Dennis J.

    1989-01-01

    The present stature and current research directions of photovoltaic arrays as primary power systems for space are reviewed. There have recently been great advances in the technology of thin-film solar cells for terrestrial applications. In a thin-film solar cell the thickness of the active element is only a few microns; transfer of this technology to space arrays could result in ultralow-weight solar arrays with potentially large gains in specific power. Recent advances in thin-film solar cells are reviewed, including polycrystalline copper-indium selenide (CuInSe2) and related I-III-VI2 compounds, polycrystalline cadmium telluride and related II-VI compounds, and amorphous silicon:hydrogen and alloys. The best experimental efficiency on thin-film solar cells to date is 12 percent AMO for CuIn Se2. This efficiency is likely to be increased in the next few years. The radiation tolerance of thin-film materials is far greater than that of single-crystal materials. CuIn Se2 shows no degradation when exposed to 1 MeV electrons. Experimental evidence also suggests that most of all of the radiation damage on thin-films can be removed by a low temperature anneal. The possibility of thin-film multibandgap cascade solar cells is discussed, including the tradeoffs between monolithic and mechanically stacked cells. The best current efficiency for a cascade is 12.5 percent AMO for an amorphous silicon on CuInSe2 multibandgap combination. Higher efficiencies are expected in the future. For several missions, including solar-electric propulsion, a manned Mars mission, and lunar exploration and manufacturing, thin-film photovolatic arrays may be a mission-enabling technology.

  7. Advanced materials for multilayer mirrors for extreme ultraviolet solar astronomy.

    PubMed

    Bogachev, S A; Chkhalo, N I; Kuzin, S V; Pariev, D E; Polkovnikov, V N; Salashchenko, N N; Shestov, S V; Zuev, S Y

    2016-03-20

    We provide an analysis of contemporary multilayer optics for extreme ultraviolet (EUV) solar astronomy in the wavelength ranges: λ=12.9-13.3  nm, λ=17-21  nm, λ=28-33  nm, and λ=58.4  nm. We found new material pairs, which will make new spaceborne experiments possible due to the high reflection efficiencies, spectral resolution, and long-term stabilities of the proposed multilayer coatings. In the spectral range λ=13  nm, Mo/Be multilayer mirrors were shown to demonstrate a better ratio of reflection efficiency and spectral resolution compared with the commonly used Mo/Si. In the spectral range λ=17-21  nm, a new multilayer structure Al/Si was proposed, which had higher spectral resolution along with comparable reflection efficiency compared with the commonly used Al/Zr multilayer structures. In the spectral range λ=30  nm, the Si/B4C/Mg/Cr multilayer structure turned out to best obey reflection efficiency and long-term stability. The B4C and Cr layers prevented mutual diffusion of the Si and Mg layers. For the spectral range λ=58  nm, a new multilayer Mo/Mg-based structure was developed; its reflection efficiency and long-term stability have been analyzed. We also investigated intrinsic stresses inherent for most of the multilayer structures and proposed possibilities for stress elimination.

  8. Performance of High-Efficiency Advanced Triple-Junction Solar Panels for the LILT Mission Dawn

    NASA Technical Reports Server (NTRS)

    Fatemi, Navid S.; Sharma, Surya; Buitrago, Oscar; Sharps, Paul R.; Blok, Ron; Kroon, Martin; Jalink, Cees; Harris, Robin; Stella, Paul; Distefano, Sal

    2005-01-01

    NASA's Discovery Mission Dawn is designed to (LILT) conditions. operate within the solar system's Asteroid belt, where the large distance from the sun creates a low-intensity, low-temperature (LILT) condition. To meet the mission power requirements under LlLT conditions, very high-efficiency multi-junction solar cells were selected to power the spacecraft to be built by Orbital Sciences Corporation (OSC) under contract with JPL. Emcore's InGaP/InGaAs/Ge advanced triple-junction (ATJ) solar cells, exhibiting an average air mass zero (AMO) efficiency of greater than 27.6% (one-sun, 28 C), were used to populate the solar panels [1]. The two solar array wings, to be built by Dutch Space, with 5 large- area panels each (total area of 36.4 sq. meters) are projected to produce between 10.3 kWe and 1.3 kWe of end-of life (EOL) power in the 1.0 to 3.0 AU range, respectively. The details of the solar panel design, testing and power analysis are presented.

  9. Newman Unit 1 advanced solar repowering advanced conceptual design. Final report

    SciTech Connect

    1982-04-01

    The Newman Unit 1 solar repowering design is a water/steam central receiver concept supplying superheated steam. The work reported is to develop a refined baseline conceptual design that has potential for construction and operation by 1986, makes use of existing solar thermal technology, and provides the best economics for this application. Trade studies performed in the design effort are described, both for the conceptual design of the overall system and for the subsystem conceptual design. System-level functional requirements, design, operation, performance, cost, safety, environmental, institutional, and regulatory considerations are described. Subsystems described include the collector, receiver, fossil energy, electrical power generating, and master control subsystems, site and site facilities. The conceptual design, cost, and performance of each subsystem is discussed at length. A detailed economic analysis of the repowered unit is made to realistically assess the economics of the first repowered unit using present cost data for a limited production level for solar hardware. Finally, a development plan is given, including the design, procurement, construction, checkout, startup, performance validation, and commercial operation. (LEW)

  10. CPV module design optimization for advanced multi-junction solar cell concepts

    NASA Astrophysics Data System (ADS)

    Steiner, Marc; Kiefel, Peter; Siefer, Gerald; Wiesenfarth, Maike; Dimroth, Frank; Krause, Rainer; Gombert, Andreas; Bett, Andreas W.

    2015-09-01

    A network model for multi-junction solar cells has been combined with ray tracing and finite element simulations of a Fresnel lens in order to interpret experimentally derived measurement results. This combined model reveals a good agreement between simulation and measurement for advanced four-junction solar cells under a Fresnel lens when the cell-to-lens distance was varied. Thus, the effect of fill factor drop caused by distributed series resistance losses due to chromatic aberration is well described by this model. Eventually, this model is used to calculate I-V characteristics of a four-junction cell, as well as of a upright metamorphic and lattice-matched triple-junction solar cell under the illumination profile of a Fresnel lens. A significant fill factor drop at distinct cell-to-lens distances was found for all three investigated solar cell types. In this work we discuss how this fill factor drop can be avoided. It is shown that already a halving of the sheet resistance within one of the lateral conduction layer in the solar cell increases the module efficiency significantly.

  11. Badhwar-O'Neil 2007 Galactic Cosmic Ray (GCR) Model Using Advanced Composition Explorer (ACE) Measurements for Solar Cycle 23

    NASA Technical Reports Server (NTRS)

    ONeill, P. M.

    2007-01-01

    Advanced Composition Explorer (ACE) satellite measurements of the galactic cosmic ray flux and correlation with the Climax Neutron Monitor count over Solar Cycle 23 are used to update the Badhwar O'Neill Galactic Cosmic Ray (GCR) model.

  12. The effect of the low Earth orbit environment on space solar cells: Results of the Advanced Photovoltaic Experiment (S0014)

    NASA Technical Reports Server (NTRS)

    Brinker, David J.; Hickey, John R.; Scheiman, David A.

    1993-01-01

    The results of post-flight performance testing of the solar cells flown on the Advanced Photovoltaic Experiment are reported. Comparison of post-flight current-voltage characteristics with similar pre-flight data revealed little or no change in solar cell conversion efficiency, confirming the reliability and endurance of space photovoltaic cells. This finding is in agreement with the lack of significant physical changes in the solar cells despite nearly six years in the low Earth orbit environment.

  13. Comparison of advanced engines for parabolic dish solar thermal power plants

    NASA Technical Reports Server (NTRS)

    Fujita, T.; Bowyer, J. M.; Gajanana, B. C.

    1980-01-01

    A paraboloidal dish solar thermal power plant produces electrical energy by a two-step conversion process. The collector subsystem is composed of a two-axis tracking paraboloidal concentrator and a cavity receiver. The concentrator focuses intercepted sunlight (direct, normal insolation) into a cavity receiver whose aperture encircles the focal point of the concentrator. At the internal wall of the receiver the electromagnetic radiation is converted to thermal energy. A heat engine/generator assembly then converts the thermal energy captured by the receiver to electricity. Developmental activity has been concentrated on small power modules which employ 11- to 12-meter diameter dishes to generate nominal power levels of approximately 20 kWe. A comparison of advanced heat engines for the dish power module is presented in terms of the performance potential of each engine with its requirements for advanced technology development. Three advanced engine possibilities are the Brayton (gas turbine), Brayton/Rankine combined cycle, and Stirling engines.

  14. The Advanced Technology Solar Telescope: Science Goals, Design and Project Status. (Invited)

    NASA Astrophysics Data System (ADS)

    Rimmele, T.; Keil, S. L.; Wagner, J.

    2009-12-01

    The 4m Advance Technology Solar Telescope (ATST) on Haleakala will be the most powerful solar telescope and the world’s leading resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun’s output. The project is about to enter the construction phase and is expected to be fully commissioned in 2017. A brief overview of the science goals and observational requirements of the ATST will be given followed by a summary of the design status of the telescope and its instrumentation will during which the technical and engineering challenges the ATST project faces will be discussed. ATST will provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona. With its 4 m aperture, ATST will resolve features at 0.”03 (20km on the sun) at visible wavelengths. The science requirement for polarimetric sensitivity (10-5 relative to intensity) and accuracy (5x10-4 relative to intensity) place strong constraints on the polarization analysis and calibration units. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the Coude lab facility. A few examples of the many unique science capabilities of the 4m ATST will be discussed. The initial set of first generation instruments includes: 1: the Visible Broadband Imager will provide images at the highest possible spatial and temporal resolution at a number of specified wavelengths in the range from 390 nm to 860 nm. 2: the Visible Spectro-Polarimeter will provide precision vector field measurements simultaneously at diverse wavelengths in the visible spectrum and thus deliver quantitative diagnostics of the magnetic field vector as a function of height in the solar atmosphere, along with the associated variation of the thermodynamic properties. 3: the Diffraction-Limited Near-Infrared Spectro

  15. Advancing Residential Retrofits in Atlanta

    SciTech Connect

    Jackson, Roderick K; Kim, Eyu-Jin; Roberts, Sydney; Stephenson, Robert

    2012-07-01

    This report will summarize the home energy improvements performed in the Atlanta, GA area. In total, nine homes were retrofitted with eight of the homes having predicted source energy savings of approximately 30% or greater based on simulated energy consumption.

  16. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Russell, Tiffany; Martinez, Armando; Boyd, Darren; SanSoucie, Michael; Farmer, Brandon; Schneider, Todd; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans/initial results.

  17. Advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) Small Spacecraft System

    NASA Technical Reports Server (NTRS)

    Lockett, Tiffany Russell; Martinez, Armando; Boyd, Darren; SanSouice, Michael; Farmer, Brandon; Schneider, Todd; Laue, Greg; Fabisinski, Leo; Johnson, Les; Carr, John A.

    2015-01-01

    This paper describes recent advancements of the Lightweight Integrated Solar Array and Transceiver (LISA-T) currently being developed at NASA's Marshall Space Flight Center. The LISA-T array comprises a launch stowed, orbit deployed structure on which thin-film photovoltaic (PV) and antenna devices are embedded. The system provides significant electrical power generation at low weights, high stowage efficiency, and without the need for solar tracking. Leveraging high-volume terrestrial-market PVs also gives the potential for lower array costs. LISA-T is addressing the power starvation epidemic currently seen by many small-scale satellites while also enabling the application of deployable antenna arrays. Herein, an overview of the system and its applications are presented alongside sub-system development progress and environmental testing plans.

  18. Photocatalytic Removal of Microcystin-LR by Advanced WO3-Based Nanoparticles under Simulated Solar Light

    PubMed Central

    Zhao, Chao; Li, Dawei; Feng, Chuanping; Zhang, Zhenya; Sugiura, Norio; Yang, Yingnan

    2015-01-01

    A series of advanced WO3-based photocatalysts including CuO/WO3, Pd/WO3, and Pt/WO3 were synthesized for the photocatalytic removal of microcystin-LR (MC-LR) under simulated solar light. In the present study, Pt/WO3 exhibited the best performance for the photocatalytic degradation of MC-LR. The MC-LR degradation can be described by pseudo-first-order kinetic model. Chloride ion (Cl−) with proper concentration could enhance the MC-LR degradation. The presence of metal cations (Cu2+ and Fe3+) improved the photocatalytic degradation of MC-LR. This study suggests that Pt/WO3 photocatalytic oxidation under solar light is a promising option for the purification of water containing MC-LR. PMID:25884038

  19. Conceptual design of an advanced water/steam receiver for a solar thermal central power system

    NASA Astrophysics Data System (ADS)

    Wu, S. F.; Narayanan, T. V.; Gorman, D. N.

    1981-06-01

    This paper describes the conceptual design of an advanced water/steam receiver for a commercial-scale solar central receiver thermal power system. The objective was to develop a receiver concept featuring an optimum combination of cost, performance, and reliability. While interfaces with other major subsystems of the complete power plant were recognized, emphasis was on the design and performance of the receiver. The baseline thermal rating of this receiver was 550 MW, and the steam outlet conditions were 12,860 kPa and 516 C. After technical and economic evaluations, a quad-cavity, natural-circulation concept was selected as the preferred receiver design. It consists of four separate cavities in a single receiver unit, each cavity receiving concentrated solar energy from one quadrant of a surrounding heliostat field.

  20. Advanced Research Deposition System (ARDS) for processing CdTe solar cells

    NASA Astrophysics Data System (ADS)

    Barricklow, Keegan Corey

    CdTe solar cells have been commercialized at the Gigawatt/year level. The development of volume manufacturing processes for next generation CdTe photovoltaics (PV) with higher efficiencies requires research systems with flexibility, scalability, repeatability and automation. The Advanced Research Deposition Systems (ARDS) developed by the Materials Engineering Laboratory (MEL) provides such a platform for the investigation of materials and manufacturing processes necessary to produce the next generation of CdTe PV. Limited by previous research systems, the ARDS was developed to provide process and hardware flexibility, accommodating advanced processing techniques, and capable of producing device quality films. The ARDS is a unique, in-line process tool with nine processing stations. The system was designed, built and assembled at the Materials Engineering Laboratory. Final assembly, startup, characterization and process development are the focus of this research. Many technical challenges encountered during the startup of the ARDS were addressed in this research. In this study, several hardware modifications needed for the reliable operation of the ARDS were designed, constructed and successfully incorporated into the ARDS. The effect of process condition on film properties for each process step was quantified. Process development to achieve 12% efficient baseline solar cell required investigation of discrete processing steps, troubleshooting process variation, and developing performance correlations. Subsequent to this research, many advances have been demonstrated with the ARDS. The ARDS consistently produces devices of 12% +/-.5% by the process of record (POR). The champion cell produced to date utilizing the ARDS has an efficiency of 16.2% on low cost commercial sodalime glass and utilizes advanced films. The ARDS has enabled investigation of advanced concepts for processing CdTe devices including, Plasma Cleaning, Plasma Enhanced Closed Space Sublimation

  1. Advances and recent trends in heterogeneous photo(electro)-catalysis for solar fuels and chemicals.

    PubMed

    Highfield, James

    2015-04-15

    In the context of a future renewable energy system based on hydrogen storage as energy-dense liquid alcohols co-synthesized from recycled CO2, this article reviews advances in photocatalysis and photoelectrocatalysis that exploit solar (photonic) primary energy in relevant endergonic processes, viz., H2 generation by water splitting, bio-oxygenate photoreforming, and artificial photosynthesis (CO2 reduction). Attainment of the efficiency (>10%) mandated for viable techno-economics (USD 2.00-4.00 per kg H2) and implementation on a global scale hinges on the development of photo(electro)catalysts and co-catalysts composed of earth-abundant elements offering visible-light-driven charge separation and surface redox chemistry in high quantum yield, while retaining the chemical and photo-stability typical of titanium dioxide, a ubiquitous oxide semiconductor and performance "benchmark". The dye-sensitized TiO2 solar cell and multi-junction Si are key "voltage-biasing" components in hybrid photovoltaic/photoelectrochemical (PV/PEC) devices that currently lead the field in performance. Prospects and limitations of visible-absorbing particulates, e.g., nanotextured crystalline α-Fe2O3, g-C3N4, and TiO2 sensitized by C/N-based dopants, multilayer composites, and plasmonic metals, are also considered. An interesting trend in water splitting is towards hydrogen peroxide as a solar fuel and value-added green reagent. Fundamental and technical hurdles impeding the advance towards pre-commercial solar fuels demonstration units are considered.

  2. Systems and methods for advanced ultra-high-performance InP solar cells

    DOEpatents

    Wanlass, Mark

    2017-03-07

    Systems and Methods for Advanced Ultra-High-Performance InP Solar Cells are provided. In one embodiment, an InP photovoltaic device comprises: a p-n junction absorber layer comprising at least one InP layer; a front surface confinement layer; and a back surface confinement layer; wherein either the front surface confinement layer or the back surface confinement layer forms part of a High-Low (HL) doping architecture; and wherein either the front surface confinement layer or the back surface confinement layer forms part of a heterointerface system architecture.

  3. Analysis of advanced vapor source for cadmium telluride solar cell manufacturing

    NASA Astrophysics Data System (ADS)

    Khetani, Tejas Harshadkumar

    A thin film CdS/CdTe solar cell manufacturing line has been developed in the Materials Engineering Laboratory at Colorado State University. The original design incorporated infrared lamps for heating the vapor source. This system has been redesigned to improve the energy efficiency of the system, allow co-sublimation and allow longer run time before the sources have to be replenished. The advanced vapor source incorporates conduction heating with heating elements embedded in graphite. The advanced vapor source was modeled by computational fluid dynamics (CFD). From these models, the required maximum operating temperature of the element was determined to be 720 C for the processing of CdS/CdTe solar cells. Nichrome and Kanthal A1 were primarily selected for this application at temperature of 720 °C in vacuum with oxygen partial pressure. Research on oxidation effects and life due to oxidation as well as creep deformation was done, and Nichrome was found more suitable for this application. A study of the life of the Nichrome heating elements in this application was conducted and the estimate of life is approximately 1900 years for repeated on-off application. This is many orders of magnitude higher than the life of infrared heat lamps. Ceramic cement based on aluminum oxide (Resbond 920) is used for bonding the elements to the graphite. Thermodynamic calculations showed that this cement is inert to the heating element. An earlier design of the advanced source encountered failure of the element. The failed element was studies by scanning electron microscopy and the failure was attributed to loss of adhesion between the graphite and the ceramic element. The design has been modified and the advanced vapor source is currently in operation.

  4. 26 CFR 1.23-1 - Residential energy credit.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... which he received a loan of $5,000 from the Federal Solar-Energy and Energy Conservation Bank. Assume... 26 Internal Revenue 1 2013-04-01 2013-04-01 false Residential energy credit. 1.23-1 Section 1.23-1... Rates During A Taxable Year § 1.23-1 Residential energy credit. (a) General rule. Section 23 or...

  5. 26 CFR 1.23-1 - Residential energy credit.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... which he received a loan of $5,000 from the Federal Solar-Energy and Energy Conservation Bank. Assume... 26 Internal Revenue 1 2010-04-01 2010-04-01 true Residential energy credit. 1.23-1 Section 1.23-1... Rates During A Taxable Year § 1.23-1 Residential energy credit. (a) General rule. Section 23 or...

  6. 26 CFR 1.23-1 - Residential energy credit.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... which he received a loan of $5,000 from the Federal Solar-Energy and Energy Conservation Bank. Assume... 26 Internal Revenue 1 2014-04-01 2013-04-01 true Residential energy credit. 1.23-1 Section 1.23-1... Rates During A Taxable Year § 1.23-1 Residential energy credit. (a) General rule. Section 23 or...

  7. 26 CFR 1.23-1 - Residential energy credit.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... which he received a loan of $5,000 from the Federal Solar-Energy and Energy Conservation Bank. Assume... 26 Internal Revenue 1 2012-04-01 2012-04-01 false Residential energy credit. 1.23-1 Section 1.23-1... Rates During A Taxable Year § 1.23-1 Residential energy credit. (a) General rule. Section 23 or...

  8. 26 CFR 1.23-1 - Residential energy credit.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... which he received a loan of $5,000 from the Federal Solar-Energy and Energy Conservation Bank. Assume... 26 Internal Revenue 1 2011-04-01 2009-04-01 true Residential energy credit. 1.23-1 Section 1.23-1... Rates During A Taxable Year § 1.23-1 Residential energy credit. (a) General rule. Section 23 or...

  9. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2014-01-01

    Testing was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by Space Systems Loral, LLC (SSL). The ATJ coupon was a small, 4-cell, two-string configuration of flight-type design that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge (ESD) testing at two string voltages (100 V, 150 V) and four string currents (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micro-seconds to 2.75 milli-seconds. All TSAs occurred at a string voltage of 150 V. Post-ESD functional testing showed that no degradation occurred due to the TSA events. These test results point to a robust design for application to a high-current, high-power mission.

  10. Oxidative decomposition of p-nitroaniline in water by solar photo-Fenton advanced oxidation process.

    PubMed

    Sun, Jian-Hui; Sun, Sheng-Peng; Fan, Mao-Hong; Guo, Hui-Qin; Lee, Yi-Fan; Sun, Rui-Xia

    2008-05-01

    The degradation of p-nitroaniline (PNA) in water by solar photo-Fenton advanced oxidation process was investigated in this study. The effects of different reaction parameters including pH value of solutions, dosages of hydrogen peroxide and ferrous ion, initial PNA concentration and temperature on the degradation of PNA have been studied. The optimum conditions for the degradation of PNA in water were considered to be: the pH value at 3.0, 10 mmol L(-1) H(2)O(2), 0.05 mmol L(-1) Fe(2+), 0.072-0.217 mmol L(-1) PNA and temperature at 20 degrees C. Under the optimum conditions, the degradation efficiencies of PNA were more than 98% within 30 min reaction. The degradation characteristic of PNA showed that the conjugated pi systems of the aromatic ring in PNA molecules were effectively destructed. The experimental results indicated solar photo-Fenton process has more advantages compared with classical Fenton process, such as higher oxidation power, wider working pH range, lower ferrous ion usage, etc. Furthermore, the present study showed the potential use of solar photo-Fenton process for PNA containing wastewater treatment.

  11. Overview of NASA's Space Solar Power Technology Advanced Research and Development Program

    NASA Technical Reports Server (NTRS)

    Howell, Joe; Mankins, John C.; Davis, N. Jan (Technical Monitor)

    2001-01-01

    Large solar power satellite (SPS) systems that might provide base load power into terrestrial markets were examined extensively in the 1970s by the US Department of Energy (DOE) and the National Aeronautics and Space Administration (NASA). Following a hiatus of about 15 years, the subject of space solar power (SSP) was reexamined by NASA from 1995-1997 in the 'fresh look' study, and during 1998 in an SSP 'concept definition study', and during 1999-2000 in the SSP Exploratory Research and Technology (SERT) program. As a result of these efforts, during 2001, NASA has initiated the SSP Technology Advanced Research and Development (STAR-Dev) program based on informed decisions. The goal of the STAR-Dev program is to conduct preliminary strategic technology research and development to enable large, multi-megawatt to gigawatt-class space solar power (SSP) systems and wireless power transmission (WPT) for government missions and commercial markets (in-space and terrestrial). Specific objectives include: (1) Release a NASA Research Announcement (NRA) for SSP Projects; (2) Conduct systems studies; (3) Develop Component Technologies; (4) Develop Ground and Flight demonstration systems; and (5) Assess and/or Initiate Partnerships. Accomplishing these objectives will allow informed future decisions regarding further SSP and related research and development investments by both NASA management and prospective external partners. In particular, accomplishing these objectives will also guide further definition of SSP and related technology roadmaps including performance objectives, resources and schedules; including 'multi-purpose' applications (commercial, science, and other government).

  12. Efficient nanorod-based amorphous silicon solar cells with advanced light trapping

    NASA Astrophysics Data System (ADS)

    Kuang, Y.; van Lare, M. C.; Veldhuizen, L. W.; Polman, A.; Rath, J. K.; Schropp, R. E. I.

    2015-11-01

    We present a simple, low-cost, and scalable approach for the fabrication of efficient nanorod-based solar cells. Templates with arrays of self-assembled ZnO nanorods with tunable morphology are synthesized by chemical bath deposition using a low process temperature at 80 °C. The nanorod templates are conformally coated with hydrogenated amorphous silicon light absorber layers of 100 nm and 200 nm thickness. An initial efficiency of up to 9.0% is achieved for the optimized design. External quantum efficiency measurements on the nanorod cells show a substantial photocurrent enhancement both in the red and the blue parts of the solar spectrum. Key insights in the light trapping mechanisms in these arrays are obtained via a combination of three-dimensional finite-difference time-domain simulations, optical absorption, and external quantum efficiency measurements. Front surface patterns enhance the light incoupling in the blue, while rear side patterns lead to enhanced light trapping in the red. The red response in the nanorod cells is limited by absorption in the patterned Ag back contact. With these findings, we develop and experimentally realize a further advanced design with patterned front and back sides while keeping the Ag reflector flat, showing significantly enhanced scattering from the back reflector with reduced parasitic absorption in the Ag and thus higher photocurrent generation. Many of the findings in this work can serve to provide insights for further optimization of nanostructures for thin-film solar cells in a broad range of materials.

  13. Full potential of radial junction Si thin film solar cells with advanced junction materials and design

    NASA Astrophysics Data System (ADS)

    Qian, Shengyi; Misra, Soumyadeep; Lu, Jiawen; Yu, Zhongwei; Yu, Linwei; Xu, Jun; Wang, Junzhuan; Xu, Ling; Shi, Yi; Chen, Kunji; Roca i Cabarrocas, Pere

    2015-07-01

    Combining advanced materials and junction design in nanowire-based thin film solar cells requires a different thinking of the optimization strategy, which is critical to fulfill the potential of nano-structured photovoltaics. Based on a comprehensive knowledge of the junction materials involved in the multilayer stack, we demonstrate here, in both experimental and theoretical manners, the potential of hydrogenated amorphous Si (a-Si:H) thin film solar cells in a radial junction (RJ) configuration. Resting upon a solid experimental basis, we also assess a more advanced tandem RJ structure with radially stacking a-Si:H/nanocrystalline Si (nc-Si:H) PIN junctions, and show that a balanced photo-current generation with a short circuit current density of Jsc = 14.2 mA/cm2 can be achieved in a tandem RJ cell, while reducing the expensive nc-Si:H absorber thickness from 1-3 μ m (in planar tandem cells) to only 120 nm. These results provide a clearly charted route towards a high performance Si thin film photovoltaics.

  14. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, K. H.; Schneider, T. A.; Vaughn, J. A.; Hoang, B.; Wong, F.

    2014-01-01

    A test was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by SSL. The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge testing at two string voltages (100 V, 150 V) and four array current (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 µs to 2.9 ms. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission application.

  15. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2014-01-01

    Testing was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by Space Systems/Loral, LLC (SSL). The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge (ESD) testing at two string voltages (100 V, 150 V) and four array currents (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micro-seconds to 2.75 milli-seconds. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission.

  16. High Current ESD Test of Advanced Triple Junction Solar Array Coupon

    NASA Technical Reports Server (NTRS)

    Wright, Kenneth H., Jr.; Schneider, Todd A.; Vaughn, Jason A.; Hoang, Bao; Wong, Frankie

    2015-01-01

    A test was conducted on an Advanced Triple Junction (ATJ) coupon that was part of a risk reduction effort in the development of a high-powered solar array design by SSL. The ATJ coupon was a small, 4-cell, two-string configuration that has served as the basic test coupon design used in previous SSL environmental aging campaigns. The coupon has many attributes of the flight design; e.g., substrate structure with graphite face sheets, integrated by-pass diodes, cell interconnects, RTV grout, wire routing, etc. The objective of the present test was to evaluate the performance of the coupon after being subjected to induced electrostatic discharge testing at two string voltages (100 V, 150 V) and four array current (1.65 A, 2.0 A, 2.475 A, and 3.3 A). An ESD test circuit, unique to SSL solar array design, was built that simulates the effect of missing cells and strings in a full solar panel with special primary arc flashover circuitry. A total of 73 primary arcs were obtained that included 7 temporary sustained arcs (TSA) events. The durations of the TSAs ranged from 50 micros to 2.9 ms. All TSAs occurred at a string voltage of 150 V. Post-test Large Area Pulsed Solar Simulator (LAPSS), Dark I-V, and By-Pass Diode tests showed that no degradation occurred due to the TSA events. In addition, the post-test insulation resistance measured was > 50 G-ohms between cells and substrate. These test results indicate a robust design for application to a high-current, high-power mission application.

  17. Insights into real cotton-textile dyeing wastewater treatment using solar advanced oxidation processes.

    PubMed

    Soares, Petrick A; Silva, Tânia F C V; Manenti, Diego R; Souza, Selene M A G U; Boaventura, Rui A R; Vilar, Vítor J P

    2014-01-01

    Different advanced oxidation processes (AOPs) were applied to the treatment of a real cotton-textile dyeing wastewater as a pre-oxidation step to enhance the biodegradability of the recalcitrant compounds, which can be further oxidized using a biological process. Tests were conducted on a lab-scale prototype using artificial solar radiation and at pilot scale with compound parabolic collectors using natural solar radiation. The cotton-textile dyeing wastewater presents a lilac color, with a maximum absorbance peak at 641 nm, alkaline pH (pH = 8.2), moderate organic content (DOC = 152 mg C L(-1), COD = 684 mg O2 L(-1)) and low-moderate biodegradability (40 % after 28 days in Zahn-Wellens test). All the tested processes contributed to an effective decolorization and mineralization, but the most efficient process was the solar-photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 98.5% decolorization and 85.5% mineralization after less than 0.1 and 5.8 kJUV L(-1), respectively. In order to achieve a final wastewater with a COD below 250 mg O2 L(-1) (discharge limit into water bodies imposed by the Portuguese Legislation-Portaria no. 423/97 of 25 June 1997), considering the combination of a solar-photo-Fenton reaction with a biological process, the phototreatment energy required is 0.5 kJUV L(-1), consuming 7.5 mM hydrogen peroxide, resulting in 58.4% of mineralization [Formula: see text].

  18. Residential Energy Management Education.

    ERIC Educational Resources Information Center

    Mecca, Stephen J.; Robertshaw, Joseph E.

    1980-01-01

    Describes two formal programs in the area of energy management education: a Residential Energy Management Summer Institute (part of a faculty development program funded by the Department of Energy), and a Residential Energy Management curriculum for Energy Auditors. (CS)

  19. Leasing Residential PV Systems

    SciTech Connect

    Rutberg, Michael; Bouza, Antonio

    2013-11-01

    The article discusses the adoption, consequences and current market status of the leasing of residential photovoltaic systems. It addresses attributed energy savings and market potential of residential system leasing.

  20. Advanced nanostructured materials and their application for improvement of sun-light harvesting and efficiency of solar cells

    NASA Astrophysics Data System (ADS)

    Dimova-Malinovska, D.

    2016-02-01

    This review describes the application of different nanostructured materials in solar cells technology for improvement of sun-light harvesting and their efficiency. Several approaches have recently been proposed to increase the efficiency of solar cells above the theoretical limit which are based on a “photon management” concept that employs such phenomena as: (i) down-conversion, and (ii) surface plasmon resonance effect (iii) decreasing of the loss due to the reflection of the radiation, (iv) increasing of the reflection from the back contact, v) increasing of the effective solar cells surface, etc. The results demonstrate the possibility for to increasing of light harvesting, short circuit current and efficiency by application of nanomaterials in thin film and hetero-junction (HJ) solar cells. The first promising results allow an expectation for application of advanced nanomaterials in the 3d generation solar cells.

  1. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.

    1979-01-01

    This paper presents the performance and cost of four 10-MWe advanced solar thermal electric power plants sited in various regions of the continental United States. Each region has different insolation characteristics which result in varying collector field areas, plant performance, capital costs, and energy costs. The paraboloidal dish, central receiver, cylindrical parabolic trough, and compound parabolic concentrator (CPC) comprise the advanced concepts studied. This paper contains a discussion of the regional insolation data base, a description of the solar systems' performances and costs, and a presentation of a range for the forecast cost of conventional electricity by region and nationally over the next several decades.

  2. Advanced Deployable Shell-Based Composite Booms for Small Satellite Structural Applications Including Solar Sails

    NASA Technical Reports Server (NTRS)

    Fernandez, Juan M.

    2017-01-01

    State of the art deployable structures are mainly being designed for medium to large size satellites. The lack of reliable deployable structural systems for low cost, small volume, rideshare-class spacecraft severely constrains the potential for using small satellite platforms for affordable deep space science and exploration precursor missions that could be realized with solar sails. There is thus a need for reliable, lightweight, high packaging efficiency deployable booms that can serve as the supporting structure for a wide range of small satellite systems including solar sails for propulsion. The National Air and Space Administration (NASA) is currently investing in the development of a new class of advanced deployable shell-based composite booms to support future deep space small satellite missions using solar sails. The concepts are being designed to: meet the unique requirements of small satellites, maximize ground testability, permit the use of low-cost manufacturing processes that will benefit scalability, be scalable for use as elements of hierarchical structures (e.g. trusses), allow long duration storage, have high deployment reliability, and have controlled deployment behavior and predictable deployed dynamics. This paper will present the various rollable boom concepts that are being developed for 5-20 m class size deployable structures that include solar sails with the so-called High Strain Composites (HSC) materials. The deployable composite booms to be presented are being developed to expand the portfolio of available rollable booms for small satellites and maximize their length for a given packaged volume. Given that solar sails are a great example of volume and mass optimization, the booms were designed to comply with nominal solar sail system requirements for 6U CubeSats, which are a good compromise between those of smaller form factors (1U, 2U and 3U CubeSats) and larger ones (12 U and 27 U future CubeSats, and ESPA-class microsatellites). Solar

  3. Performance of evacuated tubular solar collectors in a residential heating and cooling system. Final report, 1 October 1978-30 September 1979

    SciTech Connect

    Duff, W.S.; Loef, G.O.G.

    1981-03-01

    Operation of CSU Solar House I during the heating season of 1978-1979 and during the 1979 cooling season was based on the use of systems comprising an experimental evacuated tubular solar collector, a non-freezing aqueous collection medium, heat exchange to an insulated conventional vertical cylindrical storage tank and to a built-up rectangular insulated storage tank, heating of circulating air by solar heated water and by electric auxiliary in an off-peak heat storage unit, space cooling by lithium bromide absorption chiller, and service water heating by solar exchange and electric auxiliary. Automatic system control and automatic data acquisition and computation are provided. This system is compared with others evaluated in CSU Solar Houses I, II and III, and with computer predictions based on mathematical models. Of the 69,513 MJ total energy requirement for space heating and hot water during a record cold winter, solar provided 33,281 MJ equivalent to 48 percent. Thirty percent of the incident solar energy was collected and 29 percent was delivered and used for heating and hot water. Of 33,320 MJ required for cooling and hot water during the summer, 79 percent or 26,202 MJ were supplied by solar. Thirty-five percent of the incident solar energy was collected and 26 percent was used for hot water and cooling in the summer. Although not as efficient as the Corning evacuated tube collector previously used, the Philips experimental collector provides solar heating and cooling with minimum operational problems. Improved performance, particularly for cooling, resulted from the use of a very well-insulated heat storage tank. Day time (on-peak) electric auxiliary heating was completely avoided by use of off-peak electric heat storage. A well-designed and operated solar heating and cooling system provided 56 percent of the total energy requirements for heating, cooling, and hot water.

  4. Residential mobility microsimulation models

    NASA Astrophysics Data System (ADS)

    Wang, Yifei; Wu, Lun

    2010-09-01

    Residential mobility refers to the spatial movement of individuals and households between dwellings within an urban area. This considerable amount of intra-urban movement affects the urban structure and has significant repercussions for urban transportation. In order to understand and project related impacts, a considerable number of residential mobility models has been developed and used in the regional planning process. Within this context, the history and state-of-art residential mobility models are discussed and indicated. Meanwhile, a residential mobility Microsimulation model, called URM-Microsim (Urban Residential Mobility Microsimulation), is introduced and discussed.

  5. Advanced solar dynamic space power systems perspectives, requirements and technology needs

    NASA Technical Reports Server (NTRS)

    Dustin, M. O.; Savino, J. M.; Lacy, D. E.; Migra, R. P.; Juhasz, A. J.; Coles, C. E.

    1986-01-01

    Projected NASA, Civil, Commercial, and Military missions will require space power systems of increased versatility and power levels. The Advanced Solar Dynamic (ASD) Power systems offer the potential for efficient, lightweight, survivable, relatively compact, long-lived space power systems applicable to a wide range of power levels (3 to 300 kWe), and a wide variety of orbits. The successful development of these systems could satisfy the power needs for a wide variety of these projected missions. Thus, the NASA Lewis Research Center has embarked upon an aggressive ASD reserach project under the direction of NASA's Office of Aeronautics and Space Technology (DAST). The project is being implemented through a combination of in-house and contracted efforts. Key elements of this project are missions analysis to determine the power systems requirements, systems analysis to identify the most attractive ASD power systems to meet these requirements, and to guide the technology development efforts, and technology development of key components.

  6. Recent results from advanced research on space solar cells at NASA

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.

    1990-01-01

    The NASA program in space photovoltaic research and development encompasses a wide range of emerging options for future space power systems, and includes both cell and array technology development. The long range goals are to develop technology capable of achieving 300 W/kg for planar arrays, and 300 W/sq m for concentrator arrays. InP and GaAs planar and concentrator cell technologies are under investigation for their potential high efficiency and good radiation resistance. The Advanced Photovoltaic Solar Array (APSA) program is a near term effort aimed at demonstrating 130 W/kg beginning of life specific power using thin (62 pm) silicon cells. It is intended to be technology transparent to future high efficiency cells and provides the baseline for development of the 300 W/kg array.

  7. Efficient nanorod-based amorphous silicon solar cells with advanced light trapping

    SciTech Connect

    Kuang, Y.; Lare, M. C. van; Polman, A.; Veldhuizen, L. W.; Schropp, R. E. I.; Rath, J. K.

    2015-11-14

    We present a simple, low-cost, and scalable approach for the fabrication of efficient nanorod-based solar cells. Templates with arrays of self-assembled ZnO nanorods with tunable morphology are synthesized by chemical bath deposition using a low process temperature at 80 °C. The nanorod templates are conformally coated with hydrogenated amorphous silicon light absorber layers of 100 nm and 200 nm thickness. An initial efficiency of up to 9.0% is achieved for the optimized design. External quantum efficiency measurements on the nanorod cells show a substantial photocurrent enhancement both in the red and the blue parts of the solar spectrum. Key insights in the light trapping mechanisms in these arrays are obtained via a combination of three-dimensional finite-difference time-domain simulations, optical absorption, and external quantum efficiency measurements. Front surface patterns enhance the light incoupling in the blue, while rear side patterns lead to enhanced light trapping in the red. The red response in the nanorod cells is limited by absorption in the patterned Ag back contact. With these findings, we develop and experimentally realize a further advanced design with patterned front and back sides while keeping the Ag reflector flat, showing significantly enhanced scattering from the back reflector with reduced parasitic absorption in the Ag and thus higher photocurrent generation. Many of the findings in this work can serve to provide insights for further optimization of nanostructures for thin-film solar cells in a broad range of materials.

  8. Preliminary design of an advanced Stirling system for terrestrial solar energy conversion

    NASA Technical Reports Server (NTRS)

    White, M. A.; Noble, J. E.; Emigh, S. G.; Ross, B. A.; Lehmann, G. A.

    1990-01-01

    A preliminary design was generated for an advanced Stirling conversion system (ASCS) that will be capable of delivering about 25 kW of electric power to an electric utility grid. Stirling engines are being evaluated for terrestrial solar applications. A two-year task to complete detailed design, fabrication, assembly and testing of an ASCS prototype began in April, 1990. The ASCS is designed to deliver maximum power per year over a range of solar inputs with a design life of 30 years (60,000 h). The ACSC has a long-term cost goal of about $450 per kilowatt, exclusive of the 11-m parabolic dish concentrator. The proposed system includes a Stirling engine with high-pressure hydraulic output, coupled with a bent axis variable displacement hydraulic motor and a rotary induction generator. The major thrusts of the preliminary design are described, including material selection for the hot-end components, heat transport system (reflux pool boiler) design, system thermal response, improved manufacturability, FMECA/FTA analysis, updated manufacturing cost estimate, and predicted system performance.

  9. Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants.

    PubMed

    Tsydenova, Oyuna; Batoev, Valeriy; Batoeva, Agniya

    2015-08-14

    The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes-catalyst/oxidant concentrations, incident radiation flux, and pH-need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities.

  10. Solar-Enhanced Advanced Oxidation Processes for Water Treatment: Simultaneous Removal of Pathogens and Chemical Pollutants

    PubMed Central

    Tsydenova, Oyuna; Batoev, Valeriy; Batoeva, Agniya

    2015-01-01

    The review explores the feasibility of simultaneous removal of pathogens and chemical pollutants by solar-enhanced advanced oxidation processes (AOPs). The AOPs are based on in-situ generation of reactive oxygen species (ROS), most notably hydroxyl radicals •OH, that are capable of destroying both pollutant molecules and pathogen cells. The review presents evidence of simultaneous removal of pathogens and chemical pollutants by photocatalytic processes, namely TiO2 photocatalysis and photo-Fenton. Complex water matrices with high loads of pathogens and chemical pollutants negatively affect the efficiency of disinfection and pollutant removal. This is due to competition between chemical substances and pathogens for generated ROS. Other possible negative effects include light screening, competitive photon absorption, adsorption on the catalyst surface (thereby inhibiting its photocatalytic activity), etc. Besides, some matrix components may serve as nutrients for pathogens, thus hindering the disinfection process. Each type of water/wastewater would require a tailor-made approach and the variables that were shown to influence the processes—catalyst/oxidant concentrations, incident radiation flux, and pH—need to be adjusted in order to achieve the required degree of pollutant and pathogen removal. Overall, the solar-enhanced AOPs hold promise as an environmentally-friendly way to substitute or supplement conventional water/wastewater treatment, particularly in areas without access to centralized drinking water or sewage/wastewater treatment facilities. PMID:26287222

  11. Concentrating solar power (CSP) power cycle improvements through application of advanced materials

    NASA Astrophysics Data System (ADS)

    Siefert, John A.; Libby, Cara; Shingledecker, John

    2016-05-01

    Concentrating solar power (CSP) systems with thermal energy storage (TES) capability offer unique advantages to other renewable energy technologies in that solar radiation can be captured and stored for utilization when the sun is not shining. This makes the technology attractive as a dispatchable resource, and as such the Electric Power Research Institute (EPRI) has been engaged in research and development activities to understand and track the technology, identify key technical challenges, and enable improvements to meet future cost and performance targets to enable greater adoption of this carbon-free energy resource. EPRI is also involved with technically leading a consortium of manufacturers, government labs, and research organizations to enable the next generation of fossil fired power plants with advanced ultrasupercritical (A-USC) steam temperatures up to 760°C (1400°F). Materials are a key enabling technology for both of these seemingly opposed systems. This paper discusses how major strides in structural materials for A-USC fossil fired power plants may be translated into improved CSP systems which meet target requirements.

  12. Persuasion stage in adoption theory: a cognitive response-cognitive structure assessment of source credibility and tax-incentive effects on consumer decision making for residential solar systems. [Suburbs of Baltimore

    SciTech Connect

    Batory, S.S.

    1981-01-01

    The research objective was to learn more about the consumer's acceptance or rejection process toward a major residential energy innovation, a solar-generated water heating system. An experiment was conducted that evaluated one aspect of solar's commercialization, the persuasion stage in new-product-adoption decision making. A test of source credibility and monetary incentive effects on the consumer's decision-making processes was carried out. The experiment contained two message sources: the Department of Energy (a high credibility source) and a homebuilder (a moderate credibility source), and three levels of incentives, a tax credit equal to 40% of the solar unit purchase price, a 20% tax credit, and no tax credit. Subjects were randomly assigned to either a control group or one of six experimental treatments in a 2 x 3 fixed-effects factorial design. Subjects were 226 adult homeowners drawn from the suburbs of Baltimore, Maryland. The research postulated and tested a process of acceptance or rejection of innovations which was based on a cognitive-response/cognitive-structure paradigm of decision making. This process is called the persuasion stage by adoption theorists. Cognitive responses, beliefs, attitudes, and behavioral measures were the dependent variables. Consumers were shown to confront or debate incoming information by comparing it to their existing cognitive structure. This comparison process generated cognitive responses which led to changes in beliefs, attitudes, and behavior toward the innovation. The findings confirm that the federal government's intervention in the marketplace is having a favorable effect on the adoption decision process toward solar-generated water heating.

  13. Use of solar advanced oxidation processes for wastewater treatment: Follow-up on degradation products, acute toxicity, genotoxicity and estrogenicity.

    PubMed

    Brienza, M; Mahdi Ahmed, M; Escande, A; Plantard, G; Scrano, L; Chiron, S; Bufo, S A; Goetz, V

    2016-04-01

    Wastewater tertiary treatment by advanced oxidation processes is thought to produce a treated effluent with lower toxicity than the initial influent. Here we performed tertiary treatment of a secondary effluent collected from a Waste Water Treatment Plant via homogeneous (solar/HSO5(-)/Fe(2+)) and heterogeneous (solar/TiO2) solar advanced oxidation aiming at the assessment of their effectiveness in terms of contaminants' and toxicity abatement in a plain solar reactor. A total of 53 organic contaminants were qualitatively identified by liquid chromatography coupled to high-resolution mass spectrometry after solid phase extraction. Solar advanced oxidation totally or partially removed the major part of contaminants detected within 4.5 h. Standard toxicity tests were performed using Vibrio fischeri, Daphnia magna, Pseudokirchneriella subcapitata and Brachionus calyciflorus organisms to evaluate acute and chronic toxicity in the secondary or tertiary effluents, and the EC50% was calculated. Estrogenic and genotoxic tests were carried out in an attempt to obtain an even sharper evaluation of potential hazardous effects due to micropollutants or their degradation by-products in wastewater. Genotoxic effects were not detected in effluent before or after treatment. However, we observed relevant estrogenic activity due to the high sensitivity of the HELN ERα cell line.

  14. Integrated residential photovoltaic array development

    NASA Technical Reports Server (NTRS)

    Shepard, N. F., Jr.

    1981-01-01

    The design details of an optimized integrated residential photovoltaic module/array are presented. This selected design features a waterproofing and mounting scheme which was devised to simplify the installation procedures by the avoidance of complex gasketed or caulked joints, while still maintaining a high confidence that the watertight integrity of the integral roofing surface will be achieved for the design lifetime of the system. The production and installation costs for the selected module/array design are reported for a range of annual production rates as a function of the cost of solar cells.

  15. The effects of regional insolation differences upon advanced solar thermal electric power plant performance and energy costs

    NASA Technical Reports Server (NTRS)

    Latta, A. F.; Bowyer, J. M.; Fujita, T.; Richter, P. H.

    1979-01-01

    The performance and cost of the 10 MWe advanced solar thermal electric power plants sited in various regions of the continental United States were determined. The regional insolation data base is discussed. A range for the forecast cost of conventional electricity by region and nationally over the next several cades are presented.

  16. Advanced Undergraduate and Early Graduate Physics Students' Misconception about Solar Wind Flow: Evidence of Students' Difficulties in Distinguishing Paradigms

    ERIC Educational Resources Information Center

    Gross, Nicholas A.; Lopez, Ramon E.

    2009-01-01

    Anecdotal evidence has suggested that advanced undergraduate students confuse the spiral structure of the interplanetary magnetic field with the flow of the solar wind. Though it is a small study, this paper documents this misconception and begins to investigate the underlying issues behind it. We present evidence that the traditional presentation…

  17. Hydrothermal fabrication of selectively doped organic assisted advanced ZnO nanomaterial for solar driven photocatalysis.

    PubMed

    Namratha, K; Byrappa, K; Byrappa, S; Venkateswarlu, P; Rajasekhar, D; Deepthi, B K

    2015-08-01

    Hydrothermal fabrication of selectively doped (Ag(+)+Pd(3+)) advanced ZnO nanomaterial has been carried out under mild pressure temperature conditions (autogeneous; 150°C). Gluconic acid has been used as a surface modifier to effectively control the particle size and morphology of these ZnO nanoparticles. The experimental parameters were tuned to achieve optimum conditions for the synthesis of selectively doped ZnO nanomaterials with an experimental duration of 4 hr. These selectively doped ZnO nanoparticles were characterized using powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-Vis spectroscopy and scanning electron microscopy (SEM). The solar driven photocatalytic studies have been carried out for organic dyes, i.e., Procion MX-5B dye, Cibacron Brilliant Yellow dye, Indigo Carmine dye, separately and all three mixed, by using gluconic acid modified selectively doped advanced ZnO nanomaterial. The influence of catalyst, its concentration and initial dye concentration resulted in the photocatalytic efficiency of 89% under daylight.

  18. Industry Perspectives on Advanced Inverters for U.S. Solar Photovoltaic Systems. Grid Benefits, Deployment Challenges, and Emerging Solutions

    SciTech Connect

    Reiter, Emerson; Ardani, Kristen; Margolis, Robert; Edge, Ryan

    2015-09-01

    To clarify current utility strategies and other considerations related to advanced inverter deployment, we interviewed 20 representatives from 11 leading organizations closely involved with advanced inverter pilot testing, protocols, and implementation. Included were representatives from seven utilities, a regional transmission operator, an inverter manufacturer, a leading solar developer, and a consortium for grid codes and standards. Interview data represent geographically the advanced inverter activities identified in SEPA's prior survey results--most interviewed utilities serve California, Arizona, and Hawaii, though we also interviewed others from the Northeast, Mid-Atlantic, and Southeast.

  19. Advanced Architecture for Colloidal PbS Quantum Dot Solar Cells Exploiting a CdSe Quantum Dot Buffer Layer.

    PubMed

    Zhao, Tianshuo; Goodwin, Earl D; Guo, Jiacen; Wang, Han; Diroll, Benjamin T; Murray, Christopher B; Kagan, Cherie R

    2016-09-22

    Advanced architectures are required to further improve the performance of colloidal PbS heterojunction quantum dot solar cells. Here, we introduce a CdI2-treated CdSe quantum dot buffer layer at the junction between ZnO nanoparticles and PbS quantum dots in the solar cells. We exploit the surface- and size-tunable electronic properties of the CdSe quantum dots to optimize its carrier concentration and energy band alignment in the heterojunction. We combine optical, electrical, and analytical measurements to show that the CdSe quantum dot buffer layer suppresses interface recombination and contributes additional photogenerated carriers, increasing the open-circuit voltage and short-circuit current of PbS quantum dot solar cells, leading to a 25% increase in solar power conversion efficiency.

  20. Decontamination of soil washing wastewater using solar driven advanced oxidation processes.

    PubMed

    Bandala, Erick R; Velasco, Yuridia; Torres, Luis G

    2008-12-30

    Decontamination of soil washing wastewater was performed using two different solar driven advanced oxidation processes (AOPs): the photo-Fenton reaction and the cobalt/peroxymonosulfate/ultraviolet (Co/PMS/UV) process. Complete sodium dodecyl sulphate (SDS), the surfactant agent used to enhance soil washing process, degradation was achieved when the Co/PMS/UV process was used. In the case of photo-Fenton reaction, almost complete SDS degradation was achieved after the use of almost four times the actual energy amount required by the Co/PMS/UV process. Initial reaction rate in the first 15min (IR15) was determined for each process in order to compare them. Highest IR15 value was determined for the Co/PMS/UV process (0.011mmol/min) followed by the photo-Fenton reaction (0.0072mmol/min) and the dark Co/PMS and Fenton processes (IR15=0.002mmol/min in both cases). Organic matter depletion in the wastewater, as the sum of surfactant and total petroleum hydrocarbons present (measured as chemical oxygen demand, COD), was also determined for both solar driven processes. It was found that, for the case of COD, the highest removal (69%) was achieved when photo-Fenton reaction was used whereas Co/PMS/UV process yielded a slightly lower removal (51%). In both cases, organic matter removal achieved was over 50%, which can be consider proper for the coupling of the tested AOPs with conventional wastewater treatment processes such as biodegradation.

  1. QUANTIFYING THE ANISOTROPY AND SOLAR CYCLE DEPENDENCE OF '1/f' SOLAR WIND FLUCTUATIONS OBSERVED BY ADVANCED COMPOSITION EXPLORER

    SciTech Connect

    Nicol, R. M.; Chapman, S. C.; Dendy, R. O.

    2009-10-01

    The power spectrum of the evolving solar wind shows evidence of a spectral break between an inertial range (IR) of turbulent fluctuations at higher frequencies and a '1/f' like region at lower frequencies. In the ecliptic plane at approx1 AU, this break occurs approximately at timescales of a few hours and is observed in the power spectra of components of velocity and magnetic field. The '1/f' energy range is of more direct coronal origin than the IR, and carries signatures of the complex magnetic field structure of the solar corona, and of footpoint stirring in the solar photosphere. To quantify the scaling properties we use generic statistical methods such as generalized structure functions and probability density functions (PDFs), focusing on solar cycle dependence and on anisotropy with respect to the background magnetic field. We present structure function analysis of magnetic and velocity field fluctuations, using a novel technique to decompose the fluctuations into directions parallel and perpendicular to the mean local background magnetic field. Whilst the magnetic field is close to '1/f', we show that the velocity field is '1/f {sup {alpha}}' with {alpha} {ne} 1. For the velocity, the value of {alpha} varies between parallel and perpendicular fluctuations and with the solar cycle. There is also variation in {alpha} with solar wind speed. We have examined the PDFs in the fast, quiet solar wind and intriguingly, whilst parallel and perpendicular are distinct, both the B field and velocity show the same PDF of their perpendicular fluctuations, which is close to {gamma} or inverse Gumbel. These results point to distinct physical processes in the corona and to their mapping out into the solar wind. The scaling exponents obtained constrain the models for these processes.

  2. Residential load profiles for photovoltaic simulation studies

    NASA Astrophysics Data System (ADS)

    Rudisill, J. F.; Lathrop, J. W.

    In order to analyze the performance of photovoltaic (PV) systems in residential applications, it is necessary to consider the load characteristics. This paper describes a computer based model which simulates the demand of a 'typical' residential customer. Input parameters allow the model to be customized for different lifestyles and different geographical locations. Previous research has utilized hourly intervals of the time domain, based on utility averages. Since the electrical demand (and solar supply) can change instantaneously, the continuous time feature is necessary in order to accurately analyze the effect of various load management strategies. The residential load was divided into heating-ventilating-air conditioning, water heating, and diversified components. The model incorporates the interactive effects of the three components as well as temporal, meteorological, and geographic effects.

  3. High-temperature thermal storage systems for advanced solar receivers materials selections

    SciTech Connect

    Wilson, D.F.; DeVan, J.H.; Howell, M.

    1990-09-01

    Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquidus temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi{sub 2}, and initial results for containment of germanium and NiSi/NiSi{sub 2}, are presented. 7 refs., 10 figs., 4 tabs.

  4. Performance experiments with alternative advanced teleoperator control modes for a simulated solar maximum satellite repair

    NASA Technical Reports Server (NTRS)

    Das, H.; Zak, H.; Kim, W. S.; Bejczy, A. K.; Schenker, P. S.

    1992-01-01

    Experiments are described which were conducted at the JPL Advanced Teleoperator Lab to demonstrate and evaluate the effectiveness of various teleoperator control modes in the performance of a simulated Solar Max Satellite Repair (SMSR) task. THe SMSR was selected as a test because it is very rich in performance capability requirements and it actually has been performed by two EVA astronauts in the Space Shuttle Bay in 1984. The main subtasks are: thermal blanket removal; installation of a hinge attachment for electrical panel opening; opening of electrical panel; removal of electrical connectors; relining of cable bundles; replacement of electrical panel; securing parts and cables; re-mate electrical connectors; closing of electrical panel; and reinstating thermal blanket. The current performance experiments are limited to thermal blanket cutting, electrical panel unbolting and handling electrical bundles and connectors. In one formal experiment even different control modes were applied to the unbolting and reinsertion of electrical panel screws subtasks. The seven control modes are alternative combinations of manual position and rate control with force feedback and remote compliance referenced to force-torque sensor information. Force-torque sensor and end effector position data and task completion times were recorded for analysis and quantification of operator performance.

  5. MATISSE: Multi-purpose Advanced Tool for Instruments for the Solar System Exploration .

    NASA Astrophysics Data System (ADS)

    Zinzi, A.; Capria, M. T.; Antonelli, L. A.

    In planetary sciences, design, assemble and launch onboard instruments are only preliminary steps toward the final aim of converting data into scientific knowledge, as the real challenge is the data analysis and interpretation. Up to now data have been generally stored in "old style" archives, i.e. common ftp servers where the user can manually search for data browsing directories organized in a time order manner. However, as datasets to be stored and searched become particularly large, this latter task absorbs a great part of the time, subtracting time to the real scientific work. In order to reduce the time spent to search and analyze data MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration), a new set of software tools developed together with the scientific teams of the instruments involved, is under development at ASDC (ASI Science Data Center), whose experience in space missions data management is well known (e.g., \\citealt{verrecchia07,pittori09,giommi09,massaro11}) and its features and aims will be presented here.

  6. Software control of the Advanced Technology Solar Telescope enclosure PLC hardware using COTS software

    NASA Astrophysics Data System (ADS)

    Borrowman, Alastair J.; de Bilbao, Lander; Ariño, Javier; Murga, Gaizka; Goodrich, Bret; Hubbard, John R.; Greer, Alan; Mayer, Chris; Taylor, Philip

    2012-09-01

    As PLCs evolve from simple logic controllers into more capable Programmable Automation Controllers (PACs), observatories are increasingly using such devices to control complex mechanisms1, 2. This paper describes use of COTS software to control such hardware using the Advanced Technology Solar Telescope (ATST) Common Services Framework (CSF). We present the Enclosure Control System (ECS) under development in Spain and the UK. The paper details selection of the commercial PLC communication library PLCIO. Implemented in C and delivered with source code, the library separates the programmer from communication details through a simple API. Capable of communicating with many types of PLCs (including Allen-Bradley and Siemens) the API remains the same irrespective of PLC in use. The ECS is implemented in Java using the observatory's framework that provides common services for software components. We present a design following a connection-based approach where all components access the PLC through a single connection class. The link between Java and PLCIO C library is provided by a thin Java Native Interface (JNI) layer. Also presented is a software simulator of the PLC based upon the PLCIO Virtual PLC. This creates a simulator operating below the library's API and thus requires no change to ECS software. It also provides enhanced software testing capabilities prior to hardware becoming available. Results are presented in the form of communication timing test data, showing that the use of CSF, JNI and PLCIO provide a control system capable of controlling enclosure tracking mechanisms, that would be equally valid for telescope mount control.

  7. Selection of high temperature thermal energy storage materials for advanced solar dynamic space power systems

    NASA Technical Reports Server (NTRS)

    Lacy, Dovie E.; Coles-Hamilton, Carolyn; Juhasz, Albert

    1987-01-01

    Under the direction of NASA's Office of Aeronautics and Technology (OAST), the NASA Lewis Research Center has initiated an in-house thermal energy storage program to identify combinations of phase change thermal energy storage media for use with a Brayton and Stirling Advanced Solar Dynamic (ASD) space power system operating between 1070 and 1400 K. A study has been initiated to determine suitable combinations of thermal energy storage (TES) phase change materials (PCM) that result in the smallest and lightest weight ASD power system possible. To date the heats of fusion of several fluoride salt mixtures with melting points greater than 1025 K have been verified experimentally. The study has indicated that these salt systems produce large ASD systems because of their inherent low thermal conductivity and low density. It is desirable to have PCMs with high densities and high thermal conductivities. Therefore, alternate phase change materials based on metallic alloy systems are also being considered as possible TES candidates for future ASD space power systems.

  8. Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells

    SciTech Connect

    Shafarman, William N.

    2015-10-12

    This project “Advanced Precursor Reaction Processing for Cu(InGa)(SeS)2 Solar Cells”, completed by the Institute of Energy Conversion (IEC) at the University of Delaware in collaboration with the Department of Chemical Engineering at the University of Florida, developed the fundamental understanding and technology to increase module efficiency and improve the manufacturability of Cu(InGa)(SeS)2 films using the precursor reaction approach currently being developed by a number of companies. Key results included: (1) development of a three-step H2Se/Ar/H2S reaction process to control Ga distribution through the film and minimizes back contact MoSe2 formation; (2) Ag-alloying to improve precursor homogeneity by avoiding In phase agglomeration, faster reaction and improved adhesion to allow wider reaction process window; (3) addition of Sb, Bi, and Te interlayers at the Mo/precursor junction to produce more uniform precursor morphology and improve adhesion with reduced void formation in reacted films; (4) a precursor structure containing Se and a reaction process to reduce processing time to 5 minutes and eliminate H2Se usage, thereby increasing throughput and reducing costs. All these results were supported by detailed characterization of the film growth, reaction pathways, thermodynamic assessment and device behavior.

  9. High-temperature thermal storage systems for advanced solar receivers materials selections

    NASA Technical Reports Server (NTRS)

    Wilson, D. F.; Devan, J. H.; Howell, M.

    1990-01-01

    Advanced space power systems that use solar energy and Brayton or Stirling heat engines require thermal energy storage (TES) systems to operate continuously through periods of shade. The receiver storage units, key elements in both Brayton and Stirling systems, are designed to use the latent heat of fusion of phase-change materials (PCMs). The power systems under current consideration for near-future National Aeronautics and Space Administration space missions require working fluid temperatures in the 1100 to 1400 K range. The PCMs under current investigation that gave liquid temperatures within this range are the fluoride family of salts. However, these salts have low thermal conductivity, which causes large temperature gradients in the storage systems. Improvements can be obtained, however, with the use of thermal conductivity enhancements or metallic PCMs. In fact, if suitable containment materials can be found, the use of metallic PCMs would virtually eliminate the orbit associated temperature variations in TES systems. The high thermal conductivity and generally low volume change on melting of germanium and alloys based on silicon make them attractive for storage of thermal energy in space power systems. An approach to solving the containment problem, involving both chemical and physical compatibility, preparation of NiSi/NiSi2, and initial results for containment of germanium and NiSi/NiSi2, are presented.

  10. Optical design of a near-infrared imaging spectropolarimeter for the Advanced Technology Solar Telescope

    NASA Astrophysics Data System (ADS)

    Greco, Vincenzo; Cavallini, Fabio

    2013-06-01

    In designing the optics of an imaging multi-etalon spectropolarimeter as a post-focus instrument for the Advanced Technology Solar Telescope (ATST), many constraints must be considered. Among these are the large entrance pupil diameter of the telescope (4 m), the demanded large field of view (≥90 arc sec), high spectral resolving power (≥200,000), and limited field-dependent blue-shift of the instrumental profile [≤3 full width at half maximum (FWHM)], which require Fabry-Perot interferometers of large diameter (≥200 mm), lighted by highly collimated beams. This implies large optical elements and long optical paths. Moreover, to use interference pre-filters with a relatively small diameter (≤70 mm) and placed between the interferometers to reduce the inter-reflections in axial-mount, a "pupil adapter" must be included with a further increase of the optical path length. Although a multi-etalon spectropolarimeter works in quasi-monochromatic light, the Fraunhofer lines of interest cover a wide range of wavelengths (850 to 1650 nm), which demands a good chromatic aberration control. A low instrumental polarization (≤0.5%) is also required to allow a high polarimetric precision. Finally, some secondary optical paths are required to perform the initial instrumental setup and to secure the best instrumental performances. A diffraction-limited optical solution for ATST is described that fulfills all the above requirements in a relative small volume.

  11. Residential GSHPs: Efficiency With Short Payback Periods

    SciTech Connect

    Cooperman, Alissa; Dieckmann, John; Brodrick, James

    2012-04-30

    This article discusses ground source heat pumps (GSHPs) for residential application as an alternative to conventional HVAC systems. A listing of current space heating energy sources are presented which are then followed by a technology overview as advances have made GSHPs more efficient. The article concludes with potential energy savings offered by GSHPs and a brief market overview.

  12. Advances in understanding the genesis and evolution solar energetic particle events over the last two solar cycles

    NASA Astrophysics Data System (ADS)

    Vainio, Rami

    2016-04-01

    I will review the observational and modeling efforts related to solar energetic particle (SEP) events over the 23rd and 24th solar cycles. I will concentrate on large SEP events related to coronal mass ejections (CMEs), but discuss observations related to the possible role of flares in the acceleration of particles in those events, as well. The possible roles of various acceleration and transport processes in understanding the characteristics of the events will be discussed. This work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA).

  13. Overview of advanced Stirling and gas turbine engine development programs and implications for solar thermal electrical applications

    SciTech Connect

    Alger, D.

    1984-03-01

    The DOE automotive advanced engine development projects managed by the NASA Lewis Research Center were described. These included one Stirling cycle engine development and two air Brayton cycle development. Other engine research activities included: (1) an air Brayton engine development sponsored by the Gas Research Institute, and (2) plans for development of a Stirling cycle engine for space use. Current and potential use of these various engines with solar parabolic dishes were discussed.

  14. Overview of Advanced Stirling and Gas Turbine Engine Development Programs and Implications for Solar Thermal Electrical Applications

    NASA Technical Reports Server (NTRS)

    Alger, D.

    1984-01-01

    The DOE automotive advanced engine development projects managed by the NASA Lewis Research Center were described. These included one Stirling cycle engine development and two air Brayton cycle development. Other engine research activities included: (1) an air Brayton engine development sponsored by the Gas Research Institute, and (2) plans for development of a Stirling cycle engine for space use. Current and potential use of these various engines with solar parabolic dishes were discussed.

  15. Packaged residential active-solar space-conditioning system. Appendix B. CSI roof integrated air heating and domestic hot water system. Final subcontract report

    SciTech Connect

    Not Available

    1986-05-01

    This report documents the design and design development process by Contemporary Systems Inc. for a roof-integrated, air-based modular solar collector that uses conventional building practices. Contemporary Systems Inc. (CSI) tested the system their engineers designed in two houses in Walpole, New Hampshire for a twelve-month period. The system was easily installed and performed successfully throughout the test period, displaying winter energy efficiency collection ratios in excess of 30:1 on an integrated monthly basis. CSI concludes that their system can result in an in-place cost of about $100/MMBtu or less than 50% of the cost of the most current solar space and water heating system.

  16. Characterization of solar cells for space applications. Volume 6: Electrical characteristics of Spectrolab BSF, BSR, textured, 10 ohm-cm, 50 micron advanced OAST solar cells as a function of intensity, temperature, and irradiation

    NASA Technical Reports Server (NTRS)

    Anspaugh, B. E.; Downing, R. G.; Miyahira, T. F.; Weiss, R. S.

    1979-01-01

    Electrical parametric data are presented on BSF, BSR, textured 10 ohm cm, 50 micron advanced OAST cells in graphical and tabular form as functions of solar illumination intensity, temperature, and 1 MeV electron fluence.

  17. Residential photovoltaic power conditioning technology for grid connected applications

    NASA Technical Reports Server (NTRS)

    Key, T. S.; Klein, J. W.

    1982-01-01

    Major advances in photovoltaic (PV) Power Conditioning (PC) with respect to performance and low-cost potential have been made. Solutions have been obtained to interface and control problems related to adapting available inverter designs to the grid-connected, residential photovoltaic experiments. A description is presented to contributing research and development activities. Attention is given to aspects of residential systems experience, conceptual design studies, questions of optimum topology development, and promising advanced designs for residential PV provided by development efforts of the private sector.

  18. Application of a solar UV/chlorine advanced oxidation process to oil sands process-affected water remediation.

    PubMed

    Shu, Zengquan; Li, Chao; Belosevic, Miodrag; Bolton, James R; El-Din, Mohamed Gamal

    2014-08-19

    The solar UV/chlorine process has emerged as a novel advanced oxidation process for industrial and municipal wastewaters. Currently, its practical application to oil sands process-affected water (OSPW) remediation has been studied to treat fresh OSPW retained in large tailings ponds, which can cause significant adverse environmental impacts on ground and surface waters in Northern Alberta, Canada. Degradation of naphthenic acids (NAs) and fluorophore organic compounds in OSPW was investigated. In a laboratory-scale UV/chlorine treatment, the NAs degradation was clearly structure-dependent and hydroxyl radical-based. In terms of the NAs degradation rate, the raw OSPW (pH ∼ 8.3) rates were higher than those at an alkaline condition (pH = 10). Under actual sunlight, direct solar photolysis partially degraded fluorophore organic compounds, as indicated by the qualitative synchronous fluorescence spectra (SFS) of the OSPW, but did not impact NAs degradation. The solar/chlorine process effectively removed NAs (75-84% removal) and fluorophore organic compounds in OSPW in the presence of 200 or 300 mg L(-1) OCl(-). The acute toxicity of OSPW toward Vibrio fischeri was reduced after the solar/chlorine treatment. However, the OSPW toxicity toward goldfish primary kidney macrophages after solar/chlorine treatment showed no obvious toxicity reduction versus that of untreated OSPW, which warrants further study for process optimization.

  19. Strategy Guideline: High Performance Residential Lighting

    SciTech Connect

    Holton, J.

    2012-02-01

    The Strategy Guideline: High Performance Residential Lighting has been developed to provide a tool for the understanding and application of high performance lighting in the home. The high performance lighting strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner's expectations for high quality lighting.

  20. Advanced linear Fresnel optics for solar thermal energy (STE) production (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Collares-Pereira, Manuel

    2016-09-01

    stage combined with the conventional primary. But is possible to go much further in concentration ( or better yet, to go much further in CAP value - CAP= C*sinθ) by adopting Advanced LFR configurations which achieve the highest concentration possible for any given θ and do so by simultaneously conserve etendue as much as possible. This talk will present and some of these solutions and discuss their merits for the application in view. It will show that all things considered, Advanced LFR solutions, with Molten Salts operating at 565°C , have a much higher final solar to electricity conversion efficiency than the conventional solutions and thus LFR technology seems to have a future market potential (given its inherently low cost) much beyond its present very low market share.

  1. Advanced methods for light trapping in optically thin silicon solar cells

    NASA Astrophysics Data System (ADS)

    Nagel, James Richard

    2011-12-01

    The field of light trapping is the study of how best to absorb light in a thin film of material when most light either reflects away at the surface or transmits straight through to the other side. This has tremendous application to the field of photovoltaics where thin silicon films can be manufactured cheaply, but also fail to capture all of the available photons in the solar spectrum. Advancements in light trapping therefore bring us closer to the day when photovoltaic devices may reach grid parity with traditional fossil fuels on the electrical energy market. This dissertation advances our understanding of light trapping by first modeling the effects of loss in planar dielectric waveguides. The mathematical framework developed here can be used to model any arbitrary three-layer structure with mixed gain or loss and then extract the total field solution for the guided modes. It is found that lossy waveguides possess a greater number of eigenmodes than their lossless counterparts, and that these "loss guided" modes attenuate much more rapidly than conventional modes. Another contribution from this dissertation is the exploration of light trapping through the use of dielectric nanospheres embedded directly within the active layer of a thin silicon film. The primary benefit to this approach is that the device can utilize a surface nitride layer serving as an antireflective coating while still retaining the benefits of light trapping within the film. The end result is that light trapping and light injection are effectively decoupled from each other and may be independently optimized within a single photovoltaic device. The final contribution from this work is a direct numerical comparison between multiple light trapping schemes. This allows us to quantify the relative performances of various design techniques against one another and objectively determine which ideas tend to capture the most light. Using numerical simulation, this work directly compares the absorption

  2. Recent advancements in plasmon-enhanced promising third-generation solar cells

    NASA Astrophysics Data System (ADS)

    Thrithamarassery Gangadharan, Deepak; Xu, Zhenhe; Liu, Yanlong; Izquierdo, Ricardo; Ma, Dongling

    2017-01-01

    The unique optical properties possessed by plasmonic noble metal nanostructures in consequence of localized surface plasmon resonance (LSPR) are useful in diverse applications like photovoltaics, sensing, non-linear optics, hydrogen generation, and photocatalytic pollutant degradation. The incorporation of plasmonic metal nanostructures into solar cells provides enhancement in light absorption and scattering cross-section (via LSPR), tunability of light absorption profile especially in the visible region of the solar spectrum, and more efficient charge carrier separation, hence maximizing the photovoltaic efficiency. This review discusses about the recent development of different plasmonic metal nanostructures, mainly based on Au or Ag, and their applications in promising third-generation solar cells such as dye-sensitized solar cells, quantum dot-based solar cells, and perovskite solar cells.

  3. Recent advancements in plasmon-enhanced promising third-generation solar cells

    NASA Astrophysics Data System (ADS)

    Thrithamarassery Gangadharan, Deepak; Xu, Zhenhe; Liu, Yanlong; Izquierdo, Ricardo; Ma, Dongling

    2016-08-01

    The unique optical properties possessed by plasmonic noble metal nanostructures in consequence of localized surface plasmon resonance (LSPR) are useful in diverse applications like photovoltaics, sensing, non-linear optics, hydrogen generation, and photocatalytic pollutant degradation. The incorporation of plasmonic metal nanostructures into solar cells provides enhancement in light absorption and scattering cross-section (via LSPR), tunability of light absorption profile especially in the visible region of the solar spectrum, and more efficient charge carrier separation, hence maximizing the photovoltaic efficiency. This review discusses about the recent development of different plasmonic metal nanostructures, mainly based on Au or Ag, and their applications in promising third-generation solar cells such as dye-sensitized solar cells, quantum dot-based solar cells, and perovskite solar cells.

  4. Summary of flat-plate solar array project documentation. Abstracts of published documents, 1975 to June 1982

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Technologies that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and government applications at a cost per watt that is competitive with other means is investigated. Silicon refinement processes, advanced silicon sheet growth techniques, solar cell development, encapsulation, automated fabrication process technology, advanced module/array design, and module/array test and evaluation techniques are developed.

  5. Opening the Solar System: An Advanced Nuclear Spacecraft for Human Exploration

    NASA Technical Reports Server (NTRS)

    Werka, R. O.; Percy, T. K.

    2014-01-01

    Human exploration of the solar system is limited by our technology, not our imagination. We dream of a time when we can freely travel among the planets and truly become a spacefaring people. However, the current state of our technology limits our options for architecting missions to other planets. Instead of sailing the seas of space in the way that we cruise the seas of Earth, our limited propulsion technology requires us to depart Earth on a giant cluster of gas tanks and return in a lifeboat. This inefficient approach to exploration is evident in many of today's leading mission plans for human flights to Mars, asteroids, and other destinations. The cost and complexity of this approach to mission architecting makes it extremely difficult to realize our dreams of exploration beyond Low Earth Orbit (LEO). This does not need to be the case. Researchers at NASA's Marshall Space Flight Center (MSFC) have been investigating the feasibility of a new take on nuclear propulsion with the performance to enable a paradigm shift in human space exploration. During the fall of 2013, engineers at MSFC's Advanced Concepts Office developed a spacecraft concept (pictured below) around this new propulsion technology and redefined the human Mars mission to show its full potential. This spacecraft, which can be launched with a fleet of soon-to-be available SLS launch vehicles, is fueled primarily with hydrogen, and is fully reusable with no staging required. The reusable nature of this design enables a host of alternative mission architectures that more closely resemble an ocean voyage than our current piecemeal approach to exploration.

  6. Study of Extra-Solar Planets with the Advanced Fiber Optic Echelle

    NASA Technical Reports Server (NTRS)

    Noyes, Robert W.; Boyce, Joseph M. (Technical Monitor)

    2002-01-01

    This is the final report of NASA Grant NAG5-7505, for 'Study of Extra-solar Planets with the Advanced Fiber Optic Echelle'. This program was funded in response to our proposal submitted under NASA NRA 97-OSS-06, with a total period of performance from June 1, 1998 through Feb 28 2002. Principal Investigator is Robert W. Noyes; co-Investigators are Sylvain G. Korzennik (SAO), Peter Niserison (SAO), and Timothy M. Brown (High Altitude Observatory). Since the start of this program we have carried out more than 30 observing runs, typically of 5 to 7 days duration. We obtained a total of around 2000 usable observations of about 150 stars, where a typical observation consists of 3 exposures of 10 minutes each. Using this data base we detected thc two additional planetary companions to the star Upsilon Andromedae. This detection was made independently of, and essentially simultaneously with, a similar detection by the Berkeley group (Marcy et al): the fact that two data sets were completely independent and gave essentially the same orbital parameters for this three-planet system gave a strong confirmation of this important result. We also extended our previous detection of the planet orbiting Rho Coronae Borealis to get a better determination of its orbital eccentricity: e=0.13 +/- 0.05. We detected a new planet in orbit around the star HD 89744, with orbital period 256 days, semi-major axis 0.88 AU, eccentricity 0.70, and minimum mass m sini = 7.2 m(sub Jup). This discovery is significant because of the very high orbital eccentricity, arid also because HD 89744 has both high metallicity [Fe/H] and at the same time a low [C/Fe] abundance ratio.

  7. Salicylic acid degradation by advanced oxidation processes. Coupling of solar photoelectro-Fenton and solar heterogeneous photocatalysis.

    PubMed

    Garza-Campos, Benjamin; Brillas, Enric; Hernández-Ramírez, Aracely; El-Ghenymy, Abdellatif; Guzmán-Mar, Jorge Luis; Ruiz-Ruiz, Edgar J

    2016-12-05

    A 3.0 L solar flow plant with a Pt/air-diffusion (anode/cathode) cell, a solar photoreactor and a photocatalytic photoreactor filled with TiO2-coated glass spheres has been utilized to couple solar photoelectro-Fenton (SPEF) and solar heterogeneous photocatalysis (SPC) for treating a 165mgL(-1) salicylic acid solution of pH 3.0. Organics were destroyed by OH radicals formed on the TiO2 photocatalyst and at the Pt anode during water oxidation and in the bulk from Fenton's reaction between added Fe(2+) and cathodically generated H2O2, along with the photolytic action of sunlight. Poor salicylic acid removal and mineralization were attained using SPC, anodic oxidation with electrogenerated H2O2 (AO-H2O2) and coupled AO-H2O2-SPC. The electro-Fenton process accelerated the substrate decay, but with low mineralization by the formation of byproducts that are hardly destroyed by OH. The mineralization was strongly increased by SPEF due to the photolysis of products by sunlight, being enhanced by coupled SPEF-SPC due to the additional oxidation by OH at the TiO2 surface. The effect of current density on the performance of both processes was examined. The most potent SPEF-SPC process at 150mAcm(-2) yielded 87% mineralization and 13% current efficiency after consuming 6.0AhL(-1). Maleic, fumaric and oxalic acids detected as final carboxylic acids were completely removed by SPEF and SPEF-SPC.

  8. Development and fabrication of advanced cover glass for a GaAs solar cell

    SciTech Connect

    Borden, P.G.; Kaminar, N.R.; Grounner, M.

    1984-01-01

    This report summarizes work on improving solar cell conversion efficiencies by modifying the cell cover glass. Two approaches were investigated during the course of this work: grooved cover glasses to reduce the effect of top contact obscuration and secondary concentrators to improve concentrator solar cell performances in tracking modules. The grooved cover glass work used an array of metallized V shaped grooves in a thin cover glass (plastic) window to deflect incident light rays away from solar cell front surface regions covered by the solar cell electrical contact metallization onto unobstructed, optically active regions of the solar cell. Secondary concentrators are being considered for use on concentrator solar cells to improve overall system conversion efficiency and reduce receiver module cost. Secondary concentrators designed and fabricated during this project consist of small glass cones to attach directly to the top of the receiver solar cell. When appropriately designed, these secondary concentrator glass cones increase sunlight concentration on the solar cell, improve solar flux uniformity on the cell, improve system tolerance to tracking error, and allow for concentration ratios greater than can be ordinarily achieved with acrylic Fresnel lenses.

  9. Far Ultraviolet Refractive Index of Optical Materials for Solar Blind Channel (SBC) Filters for HST Advanced Camera for Surveys

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B.; Madison, Timothy J.; Petrone, Peter

    1998-01-01

    Refractive index measurements using the minimum deviation method have been carried out for prisms of a variety of far ultraviolet optical materials used in the manufacture of Solar Blind Channel (SBC) filters for the HST Advanced Camera for Surveys (ACS). Some of the materials measured are gaining popularity in a variety of high technology applications including high power excimer lasers and advanced microlithography optics operating in a wavelength region where high quality knowledge of optical material properties is sparse. Our measurements are of unusually high accuracy and precision for this wavelength region owing to advanced instrumentation in the large vacuum chamber of the Diffraction Grating Evaluation Facility (DGEF) at Goddard Space Flight Center (GSFC). Index values for CaF2, BaF2, LiF, and far ultraviolet grades of synthetic sapphire and synthetic fused silica are reported and compared with values from the literature.

  10. On the Path to SunShot. The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

    SciTech Connect

    Woodhouse, Michael; Jones-Albertus, Rebecca; Feldman, David; Fu, Ran; Horowitz, Kelsey; Chung, Donald; Jordan, Dirk; Kurtz, Sarah

    2016-05-01

    This report examines the remaining challenges to achieving the competitive photovoltaic (PV) costs and large-scale deployment envisioned under the U.S. Department of Energy's SunShot Initiative. Solar-energy cost reductions can be realized through lower PV module and balance-of-system (BOS) costs as well as improved system efficiency and reliability. Numerous combinations of PV improvements could help achieve the levelized cost of electricity (LCOE) goals because of the tradeoffs among key metrics like module price, efficiency, and degradation rate as well as system price and lifetime. Using LCOE modeling based on bottom-up cost analysis, two specific pathways are mapped to exemplify the many possible approaches to module cost reductions of 29%-38% between 2015 and 2020. BOS hardware and soft cost reductions, ranging from 54%-77% of total cost reductions, are also modeled. The residential sector's high supply-chain costs, labor requirements, and customer-acquisition costs give it the greatest BOS cost-reduction opportunities, followed by the commercial sector, although opportunities are available to the utility-scale sector as well. Finally, a future scenario is considered in which very high PV penetration requires additional costs to facilitate grid integration and increased power-system flexibility--which might necessitate even lower solar LCOEs. The analysis of a pathway to 3-5 cents/kWh PV systems underscores the importance of combining robust improvements in PV module and BOS costs as well as PV system efficiency and reliability if such aggressive long-term targets are to be achieved.

  11. Recent Advances in Interface Engineering for Planar Heterojunction Perovskite Solar Cells.

    PubMed

    Yin, Wei; Pan, Lijia; Yang, Tingbin; Liang, Yongye

    2016-06-25

    Organic-inorganic hybrid perovskite solar cells are considered as one of the most promising next-generation solar cells due to their advantages of low-cost precursors, high power conversion efficiency (PCE) and easy of processing. In the past few years, the PCEs have climbed from a few to over 20% for perovskite solar cells. Recent developments demonstrate that perovskite exhibits ambipolar semiconducting characteristics, which allows for the construction of planar heterojunction (PHJ) perovskite solar cells. PHJ perovskite solar cells can avoid the use of high-temperature sintered mesoporous metal oxides, enabling simple processing and the fabrication of flexible and tandem perovskite solar cells. In planar heterojunction materials, hole/electron transport layers are introduced between a perovskite film and the anode/cathode. The hole and electron transporting layers are expected to enhance exciton separation, charge transportation and collection. Further, the supporting layer for the perovskite film not only plays an important role in energy-level alignment, but also affects perovskite film morphology, which have a great effect on device performance. In addition, interfacial layers also affect device stability. In this review, recent progress in interfacial engineering for PHJ perovskite solar cells will be reviewed, especially with the molecular interfacial materials. The supporting interfacial layers for the optimization of perovskite films will be systematically reviewed. Finally, the challenges remaining in perovskite solar cells research will be discussed.

  12. Recent Advances, Open Questions and Future Directions in Solar-Terrestrial Research

    NASA Technical Reports Server (NTRS)

    Daglis, I. A.; Baumjohann, W.; Geiss, J.; Orsini, S.; Sarris, E. T.; Scholer, M.; Tsurutani, B. T.; Vassiliadis, D.

    1998-01-01

    Solar-terrestrial research deserves the special attention of the scientific community, both because of the attractive physics underlying the various phenomena associated with them, as well as because of the applied aspect of the sometimes destructive effects of solar-terrestrial coupling on a wide variety of technological systems.

  13. Pathways toward high-performance perovskite solar cells: review of recent advances in organo-metal halide perovskites for photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Song, Zhaoning; Watthage, Suneth C.; Phillips, Adam B.; Heben, Michael J.

    2016-04-01

    Organo-metal halide perovskite-based solar cells have been the focus of intense research over the past five years, and power conversion efficiencies have rapidly been improved from 3.8 to >21%. This article reviews major advances in perovskite solar cells that have contributed to the recent efficiency enhancements, including the evolution of device architecture, the development of material deposition processes, and the advanced device engineering techniques aiming to improve control over morphology, crystallinity, composition, and the interface properties of the perovskite thin films. The challenges and future directions for perovskite solar cell research and development are also discussed.

  14. Production of the 4.26 m ZERODUR mirror blank for the Advanced Technology Solar telescope (ATST)

    NASA Astrophysics Data System (ADS)

    Jedamzik, Ralf; Werner, Thomas; Westerhoff, Thomas

    2014-07-01

    The Daniel K. Inouye Solar Telescope (DKIST, formerly the Advanced Technology Solar Telescope, ATST) will be the most powerful solar telescope in the world. It is currently being built by the Association of Universities for Research in Astronomy (AURA) in a height of 3000 m above sea level on the mountain Haleakala of Maui, Hawaii. The primary mirror blank of diameter 4.26 m is made of the extremely low thermal expansion glass ceramic ZERODUR® of SCHOTT AG Advanced Optics. The DKIST primary mirror design is extremely challenging. With a mirror thickness of only 78 to 85 mm it is the smallest thickness ever machined on a mirror of 4.26 m in diameter. Additionally the glassy ZERODUR® casting is one of the largest in size ever produced for a 4 m class ZERODUR® mirror blank. The off axis aspherical mirror surface required sophisticated grinding procedures to achieve the specified geometrical tolerance. The small thickness of about 80 mm required special measures during processing, lifting and transport. Additionally acid etch treatment was applied to the convex back-surface and the conical shaped outer diameter surface to improve the strength of the blank. This paper reports on the challenging tasks and the achievements on the material property and dimensional specification parameter during the production of the 4.26 m ZERODUR® primary mirror blank for AURA.

  15. Techno-economic projections for advanced small solar thermal electric power plants to years 1990-2000

    NASA Technical Reports Server (NTRS)

    Fujita, T.; Manvi, R.; Roschke, E. J.; El-Gabalawi, N.; Herrera, G.; Kuo, T. J.; Chen, K. H.

    1979-01-01

    Advanced technologies applicable to solar thermal electric power systems in the 1990-200 time-frame are delineated for power applications that fulfill a wide spectrum of small power needs with primary emphasis on power ratings less than 10MWe. Projections of power system characteristics (energy and capital costs as a function of capacity factor) are made based on development of identified promising technologies and are used as the basis for comparing technology development options and combinations of these options to determine developmental directions offering potential for significant improvements. Stirling engines, Brayton/Rankine combined cycles and storage/transport concepts encompassing liquid metals, and reversible-reaction chemical systems are considered for two-axis tracking systems such as the central receiver or power tower concept and distributed parabolic dish receivers which can provide efficient low-cost solar energy collection while achieving high temperatures for efficient energy conversion. Pursuit of advanced technology across a broad front can result in post-1985 solar thermal systems having the potential of approaching the goal of competitiveness with conventional power systems.

  16. Naval Research Laboratory's programs in advanced indium phosphide solar cell development

    NASA Technical Reports Server (NTRS)

    Summers, Geoffrey P.

    1995-01-01

    The Naval Research Laboratory has been involved in developing InP solar cell technology since 1988. The purpose of these programs was to produce advanced cells for use in very high radiation environments, either as a result of operating satellites in the Van Allen belts or for very long duration missions in other orbits. Richard Statler was technical representative on the first program, with Spire Corporation as the contractor, which eventually produced several hundred, high efficiency 2 x 2 sq cm single crystal InP cells. The shallow homojunction technology which was developed in this program enabled cells to be made with AMO, one sun efficiencies greater than 19%. Many of these cells have been flown on space experiments, including PASP Plus, which have confirmed the high radiation resistance of InP cells. NRL has also published widely on the radiation response of these cells and also on radiation-induced defect levels detected by DLTS, especially the work of Rob Walters and Scott Messenger. In 1990 NRL began another Navy-sponsored program with Tim Coutts and Mark Wanlass at the National Renewable Energy Laboratory (NREL), to develop a one sun, two terminal space version of the InP-InGaAs tandem junction cell being investigated at NREL for terrestrial applications. These cells were grown on InP substrates. Several cells with AM0, one sun efficiencies greater than 22% were produced. Two 2 x 2 sq cm cells were incorporated on the STRV lA/B solar cell experiment. These were the only two junction, tandem cells on the STRV experiment. The high cost and relative brittleness of InP wafers meant that if InP cell technology were to become a viable space power source, the superior radiation resistance of InP would have to be combined with a cheaper and more robust substrate. The main technical challenge was to overcome the effect of the dislocations produced by the lattice mismatch at the interface of the two materials. Over the last few years, NRL and Steve Wojtczuk at

  17. Carbonaceous materials and their advances as a counter electrode in dye-sensitized solar cells: challenges and prospects.

    PubMed

    Kouhnavard, Mojgan; Ludin, Norasikin Ahmad; Ghaffari, Babak V; Sopian, Kamarozzaman; Ikeda, Shoichiro

    2015-05-11

    Dye-sensitized solar cells (DSSCs) serve as low-costing alternatives to silicon solar cells because of their low material and fabrication costs. Usually, they utilize Pt as the counter electrode (CE) to catalyze the iodine redox couple and to complete the electric circuit. Given that Pt is a rare and expensive metal, various carbon materials have been intensively investigated because of their low costs, high surface areas, excellent electrochemical stabilities, reasonable electrochemical activities, and high corrosion resistances. In this feature article, we provide an overview of recent studies on the electrochemical properties and photovoltaic performances of carbon-based CEs (e.g., activated carbon, nanosized carbon, carbon black, graphene, graphite, carbon nanotubes, and composite carbon). We focus on scientific challenges associated with each material and highlight recent advances achieved in overcoming these obstacles. Finally, we discuss possible future directions for this field of research aimed at obtaining highly efficient DSSCs.

  18. Nano-photonic organic solar cell architecture for advanced light management utilizing dual photonic crystals

    NASA Astrophysics Data System (ADS)

    Peer, Akshit; Biswas, Rana

    2015-09-01

    Organic solar cells have rapidly increasing efficiencies, but typically absorb less than half of the incident solar spectrum. To increase broadband light absorption, we rigorously design experimentally realizable solar cell architectures based on dual photonic crystals. Our optimized architecture consists of a polymer microlens at the air-glass interface, coupled with a photonic-plasmonic crystal at the metal cathode. The microlens focuses light on the periodic nanostructure that generates strong light diffraction. Waveguiding modes and surface plasmon modes together enhance long wavelength absorption in P3HT-PCBM. The architecture has a period of 500 nm, with absorption and photocurrent enhancement of 49% and 58%, respectively.

  19. Definition study for photovoltaic residential prototype system

    NASA Technical Reports Server (NTRS)

    Imamura, M. S.; Hulstrom, R. L.; Cookson, C.; Waldman, B. H.; Lane, R. A.

    1976-01-01

    A parametric sensitivity study and definition of the conceptual design is presented. A computer program containing the solar irradiance, solar array, and energy balance models was developed to determine the sensitivities of solar insolation and the corresponding solar array output at five sites selected for this study as well as the performance of several solar array/battery systems. A baseline electrical configuration was chosen, and three design options were recommended. The study indicates that the most sensitive parameters are the solar insolation and the inverter efficiency. The baseline PST selected is comprised of a 133 sg m solar array, 250 ampere hour battery, one to three inverters, and a full shunt regulator to limit the upper solar array voltage. A minicomputer controlled system is recommended to provide the overall control, display, and data acquisition requirements. Architectural renderings of two photovoltaic residential concepts, one above ground and the other underground, are presented. The institutional problems were defined in the areas of legal liabilities during and after installation of the PST, labor practices, building restrictions and architectural guides, and land use.

  20. Interagency Advanced Power Group Solar Photovoltaic Panel Fall meeting minutes, October 22, 1992

    SciTech Connect

    Not Available

    1992-01-01

    This report contains discussions on the following topics: Leaf, TPL, and [sup 60]Co Gamma source testing facilities; in-house photovolatic research effort; US Army's interest developing small thermophotovoatic power source for a variety of missions; charging lead acid batteries with unregulated photovolatic panels; testing of solar array panels for space applications; polycrystalline CuInSe[sub 2] CdTe PV solar cells and, current activities in the US photovolatic program.

  1. Interagency Advanced Power Group Solar Photovoltaic Panel Fall meeting minutes, October 22, 1992

    SciTech Connect

    Not Available

    1992-12-31

    This report contains discussions on the following topics: Leaf, TPL, and {sup 60}Co Gamma source testing facilities; in-house photovolatic research effort; US Army`s interest developing small thermophotovoatic power source for a variety of missions; charging lead acid batteries with unregulated photovolatic panels; testing of solar array panels for space applications; polycrystalline CuInSe{sub 2} & CdTe PV solar cells and, current activities in the US photovolatic program.

  2. Residential ventilation standards scoping study

    SciTech Connect

    McKone, Thomas E.; Sherman, Max H.

    2003-10-01

    The goals of this scoping study are to identify research needed to develop improved ventilation standards for California's Title 24 Building Energy Efficiency Standards. The 2008 Title 24 Standards are the primary target for the outcome of this research, but this scoping study is not limited to that timeframe. We prepared this scoping study to provide the California Energy Commission with broad and flexible options for developing a research plan to advance the standards. This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the ventilation needs of California residences, determining the bases for setting residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and corresponding levels of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).

  3. Energy Simulation studies in IEA/SHC Task 18 advanced glazing and associated materials for solar and building applications

    SciTech Connect

    Sullivan, R.; Selkowitz, S.; Lyons, P.

    1995-04-01

    Researchers participating in IEA/SHC Task 18 on advanced glazing materials have as their primary objective the development of new innovative glazing products such as high performance glazings, wavelength selective glazings, chromogenic optical switching devices, and light transport mechanisms that will lead to significant energy use reductions and increased comfort in commercial and residential buildings. Part of the Task 18 effort involves evaluation of the energy and comfort performance of these new glazings through the use of various performance analysis simulation tools. Eleven countries (Australia, Denmark, Finland, Germany, Italy, Netherlands, Norway, Spain, Sweden, Switzerland, and the United States) are contributing to this multi-year simulation study to better understand the complex heat transfer interactions that determine window performance. Each country has selected particular simulation programs and identified the following items to guide the simulation tasks: (1) geographic locations; (2) building types; (3) window systems and control strategies; and (4) analysis parameters of interest. This paper summarizes the results obtained thus far by several of the research organizations.

  4. Building Technologies Residential Survey

    SciTech Connect

    Secrest, Thomas J.

    2005-11-07

    Introduction A telephone survey of 1,025 residential occupants was administered in late October for the Building Technologies Program (BT) to gather information on residential occupant attitudes, behaviors, knowledge, and perceptions. The next section, Survey Results, provides an overview of the responses, with major implications and caveats. Additional information is provided in three appendices as follows: - Appendix A -- Summary Response: Provides summary tabular data for the 13 questions that, with subparts, comprise a total of 25 questions. - Appendix B -- Benchmark Data: Provides a benchmark by six categories to the 2001 Residential Energy Consumption Survey administered by EIA. These were ownership, heating fuel, geographic location, race, household size and income. - Appendix C -- Background on Survey Method: Provides the reader with an understanding of the survey process and interpretation of the results.

  5. Estimated United States Residential Energy Use in 2005

    SciTech Connect

    Smith, C A; Johnson, D M; Simon, A J; Belles, R D

    2011-12-12

    A flow chart depicting energy flow in the residential sector of the United States economy in 2005 has been constructed from publicly available data and estimates of national energy use patterns. Approximately 11,000 trillion British Thermal Units (trBTUs) of electricity and fuels were used throughout the United States residential sector in lighting, electronics, air conditioning, space heating, water heating, washing appliances, cooking appliances, refrigerators, and other appliances. The residential sector is powered mainly by electricity and natural gas. Other fuels used include petroleum products (fuel oil, liquefied petroleum gas and kerosene), biomass (wood), and on-premises solar, wind, and geothermal energy. The flow patterns represent a comprehensive systems view of energy used within the residential sector.

  6. Structural evaluation of concepts for a solar energy concentrator for Space Station advanced development program

    NASA Technical Reports Server (NTRS)

    Kenner, Winfred S.; Rhodes, Marvin D.

    1994-01-01

    Solar dynamic power systems have a higher thermodynamic efficiency than conventional photovoltaic systems; therefore they are attractive for long-term space missions with high electrical power demands. In an investigation conducted in support of a preliminary concept for Space Station Freedom, an approach for a solar dynamic power system was developed and a number of the components for the solar concentrator were fabricated for experimental evaluation. The concentrator consists of hexagonal panels comprised of triangular reflective facets which are supported by a truss. Structural analyses of the solar concentrator and the support truss were conducted using finite-element models. A number of potential component failure scenarios were postulated and the resulting structural performance was assessed. The solar concentrator and support truss were found to be adequate to meet a 1.0-Hz structural dynamics design requirement in pristine condition. However, for some of the simulated component failure conditions, the fundamental frequency dropped below the 1.0-Hz design requirement. As a result, two alternative concepts were developed and assessed. One concept incorporated a tetrahedral ring truss support for the hexagonal panels: the second incorporated a full tetrahedral truss support for the panels. The results indicate that significant improvements in stiffness can be obtained by attaching the panels to a tetrahedral truss, and that this concentrator and support truss will meet the 1.0-Hz design requirement with any of the simulated failure conditions.

  7. Advanced APCVD-processes for high-temperature grown crystalline silicon thin film solar cells.

    PubMed

    Driessen, Marion; Merkel, Benjamin; Reber, Stefan

    2011-09-01

    Crystalline silicon thin film (cSiTF) solar cells based on the epitaxial wafer-equivalent (EpiWE) concept combine advantages of wafer-based and thin film silicon solar cells. In this paper two processes beyond the standard process sequence for cSiTF cell fabrication are described. The first provides an alternative to wet chemical saw damage removal by chemical vapor etching (CVE) with hydrogen chloride in-situ prior to epitaxial deposition. This application decreases the number of process and handling steps. Solar cells fabricated with different etching processes achieved efficiencies up to 14.7%. 1300 degrees C etching temperature led to better cell results than 1200 degrees C. The second investigated process aims for an improvement of cell efficiency by implementation of a reflecting interlayer between substrate and active solar cell. Some characteristics of epitaxial lateral overgrowth (ELO) of a patterned silicon dioxide film in a lab-type reactor constructed at Fraunhofer ISE are described and first solar cell results are presented.

  8. Harmful Materials and Residential Demolition

    EPA Pesticide Factsheets

    Certain harmful or problematic materials present in residential buildings may need to be handled differently from general demolition debris. Here is a list of several specific types of materials that may be present in residential buildings.

  9. Squaraine dyes for dye-sensitized solar cells: recent advances and future challenges.

    PubMed

    Qin, Chuanjiang; Wong, Wai-Yeung; Han, Liyuan

    2013-08-01

    In the past few years, squaraine dyes have received increasing attention as a sensitizer for application in dye-sensitized solar cells. This class of dyes not only leaves open a good opportunity to afford conventional high performance dyes but also holds great promise for applications in transparent solar cells due to its low absorption intensity in the eye-sensitive region. This review provides a summary of the developments on squaraine dyes in the field of dye-sensitized solar cells and the opportunities used to improve their overall energy conversion efficiency. In particular, the main factors responsible for the low values of open-circuit voltage, short-circuit photocurrent and fill factor are discussed in detail. Future directions in research and development of near-infrared (NIR) organic materials and their applications are proposed from a personal perspective.

  10. CdS: Characterization and recent advances in CdTe solar cell performance

    SciTech Connect

    Ferekides, C.; Marinskiy, D.; Morel, D.L.

    1997-12-31

    Cadmium sulfide (CdS) films deposited by chemical bath deposition (CBD) have been used for the fabrication of high efficiency CdTe and CuIn{sub 1{minus}x}Ga{sub x}Se{sub 2} thin film solar cells. An attractive alternative deposition technology with manufacturing advantages over the CBD is the close spaced sublimation (CSS). In this work CdTe/CdS solar cells prepared entirely by the CSS process exhibited 15.0% efficiencies under global AM1.5 conditions as verified at the National Renewable Energy Laboratory. This paper reports on studies carried out on as deposited and heat treated CSS CdS films and all CSS CdTe/CdS solar cells using photoluminescence, x-ray diffraction, and I-V-T measurements.

  11. Recent advances in the transparent conducting ZnO for thin-film Si solar cells

    NASA Astrophysics Data System (ADS)

    Moon, Taeho; Shin, Gwang Su; Park, Byungwoo

    2015-11-01

    The key challenge for solar-cell development lies in the improvement of power-conversion efficiency and the reduction of fabrication cost. For thin-film Si solar cells, researches have been especially focused on the light trapping for the breakthrough in the saturated efficiencies. The ZnO-based transparent conducting oxides (TCOs) have therefore received strong attention because of their excellent light-scattering capability by the texture-etched surface and cost effectiveness through in-house fabrication. Here, we have highlighted our recent studies on the transparent conducting ZnO for thin-film Si solar cells. From the electrical properties and their degradation mechanisms, bilayer deposition and organic-acid texturing approaches for enhancing the light trapping, and finally the relation between textured ZnO and electrical cell performances are sequentially introduced in this review article. [Figure not available: see fulltext.

  12. Advanced propulsion concepts study: Comparative study of solar electric propulsion and laser electric propulsion

    NASA Technical Reports Server (NTRS)

    Forward, R. L.

    1975-01-01

    Solar electric propulsion (SEP) and laser electric propulsion (LEP) was compared. The LEP system configuration consists of an 80 kW visible laser source on earth, transmitting via an 8 m diameter adaptively controlled phased array through the atmosphere to a 4 m diameter synchronous relay mirror that tracks the LEP spacecraft. The only significant change in the SEP spacecraft for an LEP mission is the replacement of the two 3.7 m by 33.5 m solar cell arrays with a single 8 m diameter laser photovoltaic array. The solar cell array weight is decreased from 320 kg to 120 kg for an increase in payload of 200 kg and a decrease in specific mass of the power system from 20.5 kg/kW to 7.8 kg/kW.

  13. Indirect Solar Water Heating in Single-Family, Zero Energy Ready Homes

    SciTech Connect

    Aldrich, Robb

    2016-02-01

    In western Massachusetts, an affordable housing developer built a community of 20 homes with the goal of approaching zero energy consumption. In addition to excellent thermal envelopes and photovoltaic systems, the developer installed a solar domestic hot water (SDHW) system on each home. The Consortium for Advanced Residential Buildings (CARB), a U.S. Department of Energy Building America research team, commissioned some of the systems, and CARB was able to monitor detailed performance of one system for 28 months.

  14. Recent Advances in the Inverted Planar Structure of Perovskite Solar Cells.

    PubMed

    Meng, Lei; You, Jingbi; Guo, Tzung-Fang; Yang, Yang

    2016-01-19

    Inorganic-organic hybrid perovskite solar cells research could be traced back to 2009, and initially showed 3.8% efficiency. After 6 years of efforts, the efficiency has been pushed to 20.1%. The pace of development was much faster than that of any type of solar cell technology. In addition to high efficiency, the device fabrication is a low-cost solution process. Due to these advantages, a large number of scientists have been immersed into this promising area. In the past 6 years, much of the research on perovskite solar cells has been focused on planar and mesoporous device structures employing an n-type TiO2 layer as the bottom electron transport layer. These architectures have achieved champion device efficiencies. However, they still possess unwanted features. Mesoporous structures require a high temperature (>450 °C) sintering process for the TiO2 scaffold, which will increase the cost and also not be compatible with flexible substrates. While the planar structures based on TiO2 (regular structure) usually suffer from a large degree of J-V hysteresis. Recently, another emerging structure, referred to as an "inverted" planar device structure (i.e., p-i-n), uses p-type and n-type materials as bottom and top charge transport layers, respectively. This structure derived from organic solar cells, and the charge transport layers used in organic photovoltaics were successfully transferred into perovskite solar cells. The p-i-n structure of perovskite solar cells has shown efficiencies as high as 18%, lower temperature processing, flexibility, and, furthermore, negligible J-V hysteresis effects. In this Account, we will provide a comprehensive comparison of the mesoporous and planar structures, and also the regular and inverted of planar structures. Later, we will focus the discussion on the development of the inverted planar structure of perovskite solar cells, including film growth, band alignment, stability, and hysteresis. In the film growth part, several

  15. Development of advanced Si and GaAs solar cells for interplanetary missions

    NASA Technical Reports Server (NTRS)

    Strobl, G.; Uegele, P.; Kern, R.; Roy, K.; Flores, C.; Campesato, R.; Signorini, C.; Bogus, K.

    1995-01-01

    The deep space and planetary exploration project have been acquiring more and more importance and some of them are now well established both in ESA and NASA programs. This paper presents the possibility to utilize both silicon and gallium arsenide solar cells as spacecraft primary power source for missions far from the Sun, in order to overcome the drawbacks related to the utilisation of radioisotope thermoelectric generators - such as cost, safety and social acceptance. The development of solar cells for low illumination intensity and low temperature (LILT) applications is carried out in Europe by ASE (Germany) and CISE (Italy) in the frame of an ESA programme, aimed to provide the photovoltaic generators for ROSETTA: the cometary material investigation mission scheduled for launch in 2003. The LILT cells development and testing objectives are therefore focused on the following requirements: insolation intensity as low as 0.03 Solar Constant, low temperature down to -150 C and solar flare proton environment. At this stage of development, after the completion of the technology verification tests, it has been demonstrated that suitable technologies are available for the qualification of both silicon and gallium arsenide cells and both candidates have shown conversion efficiencies over 25% at an illumination of 0.03 SC and a temperature of -150 C. In particular, when measured at those LILT conditions, the newly developed 'Hl-ETA/NR-LILT' silicon solar cells have reached a conversion efficiency of 26.3%, that is the highest value ever measured on a single junction solar cell. A large quantity of both 'Hl-ETA/NR-LILT' silicon and 'GaAs/Ge-LILT' solar cells are presently under fabrication and they will be submitted to a qualification test plan, including radiation exposure, in order to verify their applicability with respect to the mission requirements. The availability of two valid options will minimize the risk for the very ambitious scientific project. The paper

  16. Residential electricity demand in Arkansas

    NASA Astrophysics Data System (ADS)

    Resendez, Ileana M.

    This study analyzes residential electricity demand in Arkansas. Explanatory variables utilized include real per capita income, residential electricity price, heating degree days, cooling degree days, and residential natural gas price. The results indicate that the income effect dominates the substitution effect given a real personal income increase and a decline in real electricity rates in the state of Arkansas during the period under study.

  17. Recent advances in visible-light-responsive photocatalysts for hydrogen production and solar energy conversion--from semiconducting TiO2 to MOF/PCP photocatalysts.

    PubMed

    Horiuchi, Yu; Toyao, Takashi; Takeuchi, Masato; Matsuoka, Masaya; Anpo, Masakazu

    2013-08-28

    The present perspective describes recent advances in visible-light-responsive photocatalysts intended to develop novel and efficient solar energy conversion technologies, including water splitting and photofuel cells. Water splitting is recognized as one of the most promising techniques to convert solar energy as a clean and abundant energy resource into chemical energy in the form of hydrogen. In recent years, increasing concern is directed to not only the development of new photocatalytic materials but also the importance of technologies to produce hydrogen and oxygen separately. Photofuel cells can convert solar energy into electrical energy by decomposing bio-related compounds and livestock waste as fuels. The advances of photocatalysts enabling these solar energy conversion technologies have been going on since the discovery of semiconducting titanium dioxide materials and have extended to organic-inorganic hybrid materials, such as metal-organic frameworks and porous coordination polymers (MOF/PCP).

  18. Recent Advances in Heliogyro Solar Sail Structural Dynamics, Stability, and Control Research

    NASA Technical Reports Server (NTRS)

    Wilkie, W. Keats; Warren, Jerry E.; Horta, Lucas G.; Lyle, Karen H.; Juang, Jer-Nan; Gibbs, S. Chad; Dowell, Earl H.; Guerrant, Daniel V.; Lawrence, Dale

    2015-01-01

    Results from recent NASA sponsored research on the structural dynamics, stability, and control characteristics of heliogyro solar sails are summarized. Specific areas under investigation include coupled nonlinear finite element analysis of heliogyro membrane blade with solar radiation pressure effects, system identification of spinning membrane structures, and solarelastic stability analysis of heliogyro solar sails, including stability during blade deployment. Recent results from terrestrial 1-g blade dynamics and control experiments on "rope ladder" membrane blade analogs, and small-scale in vacuo system identification experiments with hanging and spinning high-aspect ratio membranes will also be presented. A low-cost, rideshare payload heliogyro technology demonstration mission concept is used as a mission context for these heliogyro structural dynamics and solarelasticity investigations, and is also described. Blade torsional dynamic response and control are also shown to be significantly improved through the use of edge stiffening structural features or inclusion of modest tip masses to increase centrifugal stiffening of the blade structure. An output-only system identification procedure suitable for on-orbit blade dynamics investigations is also developed and validated using ground tests of spinning sub-scale heliogyro blade models. Overall, analytical and experimental investigations to date indicate no intractable stability or control issues for the heliogyro solar sail concept.

  19. Residential Wiring. Revised.

    ERIC Educational Resources Information Center

    Taylor, Mark

    This competency-based curriculum guide contains materials for conducting a course in residential wiring. A technically revised edition of the 1978 publication, the guide includes 28 units. Each instructional unit includes some or all of the following basic components: performance objectives, suggested activities for teachers and students,…

  20. Residential Continuing Education.

    ERIC Educational Resources Information Center

    Houle, Cyril O.

    The theme of this discursive essay is residential continuing education: its definition, its development along somewhat different lines in Europe and in America, and its practice in university centers in the United States. Continuing education includes any learning or teaching program that is based on the assumptions that the learners have studied…

  1. Residential Mechanical Precooling

    SciTech Connect

    German, a.; Hoeschele, M.

    2014-12-01

    This research conducted by the Alliance for Residential Building Innovation team evaluated mechanical air conditioner pre-cooling strategies in homes throughout the United States. EnergyPlus modeling evaluated two homes with different performance characteristics in seven climates. Results are applicable to new construction homes and most existing homes built in the last 10 years, as well as fairly efficient retrofitted homes.

  2. Residential Wiring. Second Edition.

    ERIC Educational Resources Information Center

    Taylor, Mark; And Others

    This guide is designed to assist teachers conducting a course to prepare students for entry-level employment in the residential wiring trade. Included in the guide are six instructional units and the following sections of information for teachers: guidelines in using the unit components; academic and workplace skills classifications and…

  3. Investigation of advanced nanostructured multijunction photoanodes for enhanced solar hydrogen generation via water splitting

    NASA Astrophysics Data System (ADS)

    Ishihara, Hidetaka

    As the worldwide demand for fossil-based fuel increases every day and the fossil reserve continues to be depleted, the need for alternative/renewable energy sources has gained momentum. Electric, hybrid, and hydrogen cars have been at the center of discussion lately among consumers, automobile manufacturers, and politicians, alike. The development of a fuel-cell based engine using hydrogen has been an ambitious research area over the last few decades-ever since Fujishima showed that hydrogen can be generated via the solar-energy driven photo-electrolytic splitting of water. Such solar cells are known as Photo-Electro-Chemical (PEC) solar cells. In order to commercialize this technology, various challenges associated with photo-conversion efficiency, chemical corrosion resistance, and longevity need to be overcome. In general, metal oxide semiconductors such as titanium dioxide (TiO 2, titania) are excellent candidates for PEC solar cells. Titania nanotubes have several advantages, including biocompatibility and higher chemical stability. Nevertheless, they can absorb only 5-7% of the solar spectrum which makes it difficult to achieve the higher photo-conversion efficiency required for successful commercial applications. A two-prong approach was employed to enhance photo-conversion efficiency: 1) surface modification of titania nanotubes using plasma treatment and 2) nano-capping of the titania nanotubes using titanium disilicide. The plasma surface treatment with N2 was found to improve the photo-current efficiency of titania nanotubes by 55%. Similarly, a facile, novel approach of nano-capping titania nanotubes to enhance their photocurrent response was also investigated. Electrochemically anodized titania nanotubes were capped by coating a 25 nm layer of titanium disilicide using RF magnetron sputtering technique. The optical properties of titania nanotubes were not found to change due to the capping; however, a considerable increase (40%) in the photocurrent

  4. Estimation of the monthly average daily solar radiation using geographic information system and advanced case-based reasoning.

    PubMed

    Koo, Choongwan; Hong, Taehoon; Lee, Minhyun; Park, Hyo Seon

    2013-05-07

    The photovoltaic (PV) system is considered an unlimited source of clean energy, whose amount of electricity generation changes according to the monthly average daily solar radiation (MADSR). It is revealed that the MADSR distribution in South Korea has very diverse patterns due to the country's climatic and geographical characteristics. This study aimed to develop a MADSR estimation model for the location without the measured MADSR data, using an advanced case based reasoning (CBR) model, which is a hybrid methodology combining CBR with artificial neural network, multiregression analysis, and genetic algorithm. The average prediction accuracy of the advanced CBR model was very high at 95.69%, and the standard deviation of the prediction accuracy was 3.67%, showing a significant improvement in prediction accuracy and consistency. A case study was conducted to verify the proposed model. The proposed model could be useful for owner or construction manager in charge of determining whether or not to introduce the PV system and where to install it. Also, it would benefit contractors in a competitive bidding process to accurately estimate the electricity generation of the PV system in advance and to conduct an economic and environmental feasibility study from the life cycle perspective.

  5. Advanced latent heat of fusion thermal energy storage for solar power systems

    NASA Technical Reports Server (NTRS)

    Phillips, W. M.; Stearns, J. W.

    1985-01-01

    The use of solar thermal power systems coupled with thermal energy storage (TES) is being studied for both terrestrial and space applications. In the case of terrestrial applications, it was found that one or two hours of TES could shift the insolation peak (solar noon) to coincide with user peak loads. The use of a phase change material (PCM) is attractive because of the higher energy storage density which can be achieved. However, the use of PCM has also certain disadvantages which must be addressed. Proof of concept testing was undertaken to evaluate corrosive effects and thermal ratcheting effects in a slurry system. It is concluded that the considered alkali metal/alkali salt slurry approach to TES appears to be very viable, taking into account an elimination of thermal ratcheting in storage systems and the reduction of corrosive effects. The approach appears to be useful for an employment involving temperatures applicable to Brayton or Stirling cycles.

  6. Advanced ultraviolet-resistant silver mirrors for use in solar reflectors

    DOEpatents

    Jorgensen, Gary J.; Gee, Randy

    2009-11-03

    A silver mirror construction that maintains a high percentage of hemispherical reflectance throughout the UV and visible spectrum when used in solar reflectors, comprising:a) a pressure sensitive adhesive layer positioned beneath a silver overlay;b) a polymer film disposed on the silver overlay;c) an adhesive layer positioned on the polymer film; andd) a UV screening acrylic film disposed on the adhesive layer.

  7. Recent advancements in monolithic AlGaAs/GaAs solar cells for space applications

    NASA Technical Reports Server (NTRS)

    Wickham, K. R.; Chung, B.-C.; Klausmeier-Brown, M.; Kuryla, M. S.; Ristow, M. Ladle; Virshup, G. F.; Werthen, J. G.

    1991-01-01

    High efficiency, two terminal, multijunction AlGaAs/GaAs solar cells were reproducibly made with areas of 0.5 sq cm. The multiple layers in the cells were grown by Organo Metallic Vapor Phase Epitaxy (OMVPE) on GaAs substrates in the n-p configuration. The upper AlGaAs cell has a bandgap of 1.93 eV and is connected in series to the lower GaAs cell (1.4 eV) via a metal interconnect deposited during post-growth processing. A prismatic coverglass is installed on top of the cell to reduce obscuration caused by the gridlines. The best 0.5 sq cm cell has a two terminal efficiency of 23.0 pct. at 1 sun, air mass zero (AM0) and 25 C. To date, over 300 of these cells were grown and processed for a manufacturing demonstration. Yield and efficiency data for this demonstration are presented. As a first step toward the goal of a 30 pct. efficient cell, a mechanical stack of the 0.5 sq cm cells described above, and InGaAsP (0.95 eV) solar cells was made. The best two terminal measurement to date yields an efficiency of 25.2 pct. AM0. This is the highest reported efficiency of any two terminal, 1 sun space solar cell.

  8. Si/PEDOT:PSS Hybrid Solar Cells with Advanced Antireflection and Back Surface Field Designs

    NASA Astrophysics Data System (ADS)

    Sun, Yiling; Yang, Zhenhai; Gao, Pingqi; He, Jian; Yang, Xi; Sheng, Jiang; Wu, Sudong; Xiang, Yong; Ye, Jichun

    2016-08-01

    Molybdenum oxide (MoO3) is one of most suitable antireflection (AR) layers for silicon/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (Si/PEDOT:PSS) hybrid solar cells due to its well-matched refractive index (2.1). A simulation model was employed to predict the optical characteristics of Si/PEDOT:PSS hybrid solar cells with the MoO3 layers as antireflection coatings (ARCs), as well as to analyze the loss in current density. By adding an optimum thickness of a 34-nm-thick ARC of MoO3 on the front side and an effective rear back surface field (BSF) of phosphorus-diffused N + layer at the rear side, the hybrid cells displayed higher light response in the visible and near infrared regions, boosting a short-circuit current density ( J sc) up to 28.7 mA/cm2. The average power conversion efficiency (PCE) of the Si/PEDOT:PSS hybrid solar cells was thus increased up to 11.90 %, greater than the value of 9.23 % for the reference devices.

  9. Advances in the Electrical Connection Technique of Thin Film Solar Cells on a Titanium Substrate

    NASA Astrophysics Data System (ADS)

    Zwanenburg, R.

    2008-09-01

    Dutch Space has developed a new solar blanket (the MATRIX) that consists of just Thin Film (TF) solar cells made on titanium substrates. The cells are electrically connected via a number of contact points (pressure contact only). It was found that degradation of these electrical contacts was mainly caused by a too low contact pressure. Measures have been taken to increase the contact pressure and number of contact points. An alternative contact method using conductive adhesive has been tested, but this solution failed as cell delamination from the substrate underneath the bonding spots was observed after thermal cycling tests. An improved contact system with four contact points along the cell width was implemented in an assembly of 24 new TF solar cells. Thermal cycling tests showed a stable performance of the electrical connection. Further improvements are foreseen using a new cell layout with 8 contact points. Unfortunately, cell delamination was observed after the thermal cycling testing. The adhesion between the cell coating and the molybdenum undercoat needs to be improved for the future production of TF cells.

  10. A Multi-Decadal Sample Return Campaign Will Advance Lunar and Solar System Science and Exploration by 2050

    NASA Technical Reports Server (NTRS)

    Neal, C. R.; Lawrence, S. J.

    2017-01-01

    There have been 11 missions to the Moon this century, 10 of which have been orbital, from 5 different space agencies. China became the third country to successfully soft-land on the Moon in 2013, and the second to successfully remotely operate a rover on the lunar surface. We now have significant global datasets that, coupled with the 1990s Clementine and Lunar Prospector missions, show that the sample collection is not representative of the lithologies present on the Moon. The M3 data from the Indian Chandrayaan-1 mission have identified lithologies that are not present/under-represented in the sample collection. LRO datasets show that volcanism could be as young as 100 Ma and that significant felsic complexes exist within the lunar crust. A multi-decadal sample return campaign is the next logical step in advancing our understanding of lunar origin and evolution and Solar System processes.

  11. Fully solar-driven thermo- and electrochemistry for advanced oxidation processes (STEP-AOPs) of 2-nitrophenol wastewater.

    PubMed

    Nie, Chunhong; Shao, Nan; Wang, Baohui; Yuan, Dandan; Sui, Xin; Wu, Hongjun

    2016-07-01

    The STEP (Solar Thermal Electrochemical Process) for Advanced Oxidation Processes (AOPs, combined to STEP-AOPs), fully driven by solar energy without the input of any other forms of energy and chemicals, is introduced and demonstrated from the theory to experiments. Exemplified by the persistent organic pollutant 2-nitrophenol in water, the fundamental model and practical system are exhibited for the STEP-AOPs to efficiently transform 2-nitrophenol into carbon dioxide, water, and the other substances. The results show that the STEP-AOPs system performs more effectively than classical AOPs in terms of the thermodynamics and kinetics of pollutant oxidation. Due to the combination of solar thermochemical reactions with electrochemistry, the STEP-AOPs system allows the requisite electrolysis voltage of 2-nitrophenol to be experimentally decreased from 1.00 V to 0.84 V, and the response current increases from 18 mA to 40 mA. STEP-AOPs also greatly improve the kinetics of the oxidation at 30 °C and 80 °C. As a result, the removal rate of 2-nitrophenol after 1 h increased from 19.50% at 30 °C to 32.70% at 80 °C at constant 1.90 V. Mechanistic analysis reveals that the oxidation pathway is favorably changed because of thermal effects. The tracking of the reaction displayed that benzenediol and hydroquinone are initial products, with maleic acid and formic acid as sequential carboxylic acid products, and carbon dioxide as the final product. The theory and experiments on STEP-AOPs system exemplified by the oxidation of 2-nitrophenol provide a broad basis for extension of the STEP and AOPs for rapid and efficient treatment of organic wastewater.

  12. Performance evaluation of different solar advanced oxidation processes applied to the treatment of a real textile dyeing wastewater.

    PubMed

    Manenti, Diego R; Soares, Petrick A; Silva, Tânia F C V; Módenes, Aparecido N; Espinoza-Quiñones, Fernando R; Bergamasco, Rosângela; Boaventura, Rui A R; Vilar, Vítor J P

    2015-01-01

    The performance of different solar-driven advanced oxidation processes (AOPs), such as TiO2/UV, TiO2/H2O2/UV, and Fe(2+)/H2O2/UV-visible in the treatment of a real textile effluent using a pilot plant with compound parabolic collectors (CPCs), was investigated. The influence of the main photo-Fenton reaction variables such as iron concentration (20-100 mg Fe(2+) L(-1)), pH (2.4-4.5), temperature (10-50 °C), and irradiance (22-68 WUV m(-2)) was evaluated in a lab-scale prototype using artificial solar radiation. The real textile wastewater presented a beige color, with a maximum absorbance peak at 641 nm, alkaline pH (8.1), moderate organic content (dissolved organic carbon (DOC) = 129 mg C L(-1) and chemical oxygen demand (COD) = 496 mg O2 L(-1)), and high conductivity mainly associated to the high concentration of chloride (1.1 g Cl(-) L(-1)), sulfate (0.4 g SO 4 (2 -) L(- 1)), and sodium (1.2 g Na(+) L(-1)) ions. Although all the processes tested contributed to complete decolorization and effective mineralization, the most efficient process was the solar photo-Fenton with an optimum catalyst concentration of 60 mg Fe(2+) L(-1), leading to 70 % mineralization (DOCfinal = 41 mg C L(-1); CODfinal < 150 mg O2 L(-1)) at pH 3.6, requiring a UV energy dose of 3.5 kJUV L(-1) (t 30 W = 22.4 min; [Formula: see text]; [Formula: see text]) and consuming 18.5 mM of H2O2.

  13. Conceptual design of a self-deployable, high performance parabolic concentrator for advanced solar-dynamic power systems

    NASA Technical Reports Server (NTRS)

    Dehne, Hans J.

    1991-01-01

    NASA has initiated technology development programs to develop advanced solar dynamic power systems and components for space applications beyond 2000. Conceptual design work that was performed is described. The main efforts were the: (1) conceptual design of self-deploying, high-performance parabolic concentrator; and (2) materials selection for a lightweight, shape-stable concentrator. The deployment concept utilizes rigid gore-shaped reflective panels. The assembled concentrator takes an annular shape with a void in the center. This deployable concentrator concept is applicable to a range of solar dynamic power systems of 25 kW sub e to in excess of 75 kW sub e. The concept allows for a family of power system sizes all using the same packaging and deployment technique. The primary structural material selected for the concentrator is a polyethyl ethylketone/carbon fiber composite also referred to as APC-2 or Vitrex. This composite has a nearly neutral coefficient of thermal expansion which leads to shape stable characteristics under thermal gradient conditions. Substantial efforts were undertaken to produce a highly specular surface on the composite. The overall coefficient of thermal expansion of the composite laminate is near zero, but thermally induced stresses due to micro-movement of the fibers and matrix in relation to each other cause the surface to become nonspecular.

  14. Gas chromatography: Possible application of advanced instrumentation developed for solar system exploration to space station cabin atmospheres

    NASA Technical Reports Server (NTRS)

    Carle, G. C.

    1985-01-01

    Gas chromatography (GC) technology was developed for flight experiments in solar system exploration. The GC is a powerful analytical technique with simple devices separating individual components from complex mixtures to make very sensitive quantitative and qualitative measurements. It monitors samples containing mixtures of fixed gases and volatile organic molecules. The GC was used on the Viking mission in support of life detection experiments and on the Pioneer Venus Large Probe to determine the composition of the venusian atmosphere. A flight GC is under development to study the progress and extent of STS astronaut denitrogenation prior to extravehicular activity. Advanced flight GC concepts and systems for future solar system exploration are also studied. Studies include miniature ionization detectors and associated control systems capable of detecting from ppb up to 100% concentration levels. Further miniaturization is investigated using photolithography and controlled chemical etching in silicon wafers. Novel concepts such as ion mobility drift spectroscopy and multiplex gas chromatography are also developed for future flight experiments. These powerful analytical concepts and associated hardware are ideal for the monitoring of cabin atmospheres containing potentially dangerous volatile compounds.

  15. Guidelines for residential commissioning

    SciTech Connect

    Wray, Craig P.; Walker, Iain S.; Sherman, Max H.

    2003-01-31

    Currently, houses do not perform optimally or even as many codes and forecasts predict, largely because they are field assembled and there is no consistent process to identify problems or to correct them. Residential commissioning is a solution to this problem. This guide is the culmination of a 30-month project that began in September 1999. The ultimate objective of the project is to increase the number of houses that undergo commissioning, which will improve the quality, comfort, and safety of homes for California citizens. The project goal is to lay the groundwork for a residential commissioning industry in California focused on end-use energy and non-energy issues. As such, we intend this guide to be a beginning and not an end. Our intent is that the guide will lead to the programmatic integration of commissioning with other building industry processes, which in turn will provide more value to a single site visit for people such as home energy auditors and raters, home inspectors, and building performance contractors. Project work to support the development of this guide includes: a literature review and annotated bibliography, which facilitates access to 469 documents related to residential commissioning published over the past 20 years (Wray et al. 2000), an analysis of the potential benefits one can realistically expect from commissioning new and existing California houses (Matson et al. 2002), and an assessment of 107 diagnostic tools for evaluating residential commissioning metrics (Wray et al. 2002). In this guide, we describe the issues that non-experts should consider in developing a commissioning program to achieve the benefits we have identified. We do this by providing specific recommendations about: how to structure the commissioning process, which diagnostics to use, and how to use them to commission new and existing houses. Using examples, we also demonstrate the potential benefits of applying the recommended whole-house commissioning approach to

  16. Residential lighting in Lithuania

    SciTech Connect

    Kazakevicius, Eduardas; Gadgil, Ashok; Vorsatz, Diana

    1998-09-01

    A wider use of compact fluorescent lamps (CFLs) offers a significant opportunity for Lithuania in reducing wasteful electricity consumption, and making progress towards retiring the Chernobyl-type Ignalina nuclear power reactors. The authors evaluate the conservation potential of compact fluorescent lamps for managing the residential electrical energy demand in Lithuania. The analysis is undertaken from the three-separate perspectives of (1) the national economy, (2) the consumers and (3) the utilities. In their analysis they use the most recent available data on Lithuanian residential lighting. The costs of conserved energy of 15 and 23 W CFLs range from $0.007 to 0.031 per kW-h depending on CFL price and assuming 4-hour daily lamp use. Replacing only the two most used 60 W incandescent lamps per household with CFLs would save 190 GW-h of electrical energy for Lithuania annually worth 12 million US dollars at the long run2048ginal cost. The authors compare the current residential lighting situation in Lithuania with that in Hungary and Poland, where introduction of CFLs has been much more successful. They then discuss factors that could explain the much higher CFL penetration in Hungary and Poland, barriers to immediate large-scale introduction of CFLs in Lithuania, and policy instruments that could be used for promoting the diffusion of CFLs in the residential sector of Lithuania. They conclude that future success of CFL penetration in Lithuania will depend on aggressive information and promotion efforts by at least the CFL manufacturers, and/or by any of the stakeholder institutions, (e.g., the state agencies responsible for energy and environment, electric utilities, international agencies, etc.).

  17. Detailed residential electric determination

    SciTech Connect

    Not Available

    1984-06-01

    Data on residential loads has been collected from four residences in real time. The data, measured at 5-second intervals for 53 days of continuous operation, were statistically characterized. An algorithm was developed and incorporated into the modeling code SOLCEL. Performance simulations with SOLCEL using these data as well as previous data collected over longer time intervals indicate that no significant errors in system value are introduced through the use of long-term average data.

  18. MICRO-CHP System for Residential Applications

    SciTech Connect

    Joseph Gerstmann

    2009-01-31

    This is the final report of progress under Phase I of a project to develop and commercialize a micro-CHP system for residential applications that provides electrical power, heating, and cooling for the home. This is the first phase of a three-phase effort in which the residential micro-CHP system will be designed (Phase I), developed and tested in the laboratory (Phase II); and further developed and field tested (Phase III). The project team consists of Advanced Mechanical Technology, Inc. (AMTI), responsible for system design and integration; Marathon Engine Systems, Inc. (MES), responsible for design of the engine-generator subsystem; AO Smith, responsible for design of the thermal storage and water heating subsystems; Trane, a business of American Standard Companies, responsible for design of the HVAC subsystem; and AirXchange, Inc., responsible for design of the mechanical ventilation and dehumidification subsystem.

  19. Naval Research Laboratory's programs in advanced indium phosphide solar cell development

    NASA Technical Reports Server (NTRS)

    Summers, Geoffrey P.

    1996-01-01

    The Naval Research Laboratory (NRL) has been involved in the development of solar cells for space applications since the 1960s. It quickly became apparent in this work that radiation damage caused to solar cells by electrons and protons trapped by the earth's magnetic field would seriously degrade the power output of photovoltaic arrays in extended missions. Techniques were therefore developed to harden the cells by shielding them with coverglass, etc. Ultimately, however, there is a limit to such approaches, which is determined by the radiation response of the semiconductor material employed. A desire for high efficiency and radiation resistance led to the development of alternative cell technologies such as GaAs, which has since become the technology of choice for many applications. InP cells are currently the most radiation resistant, high efficiency, planar cells known. NRL first sponsored InP solar cell technology in 1986, when Arizona State University was contracted to grow p/n cells by liquid phase epitaxy. NRL's interest in InP cells was generated by the results presented by Yamaguchi and his co-workers in the early 1980s on the remarkable radiation resistance of cells grown by diffusion of S into Zn doped p-type InP substrates. These cells also had beginning of life (BOL) efficiencies approximately 16%(AM0). Related to the radiation resistance of the cells was the fact that radiation-induced damage could be optically annealed by sunlight. Relatively large quantities of 1 x 2 cm(exp 2) diffused junction cells were made and were used on the MUSES-A and the EXOS-D satellites. These cells were also available in the U.S. through NIMCO, and were studied at NRL and elsewhere. Workers at NASA Lewis became involved in research in InP cells about the same time as NRL.

  20. Advanced Passivation Technology and Loss Factor Minimization for High Efficiency Solar Cells.

    PubMed

    Park, Cheolmin; Balaji, Nagarajan; Jung, Sungwook; Choi, Jaewoo; Ju, Minkyu; Lee, Seunghwan; Kim, Jungmo; Bong, Sungjae; Chung, Sungyoun; Lee, Youn-Jung; Yi, Junsin

    2015-10-01

    High-efficiency Si solar cells have attracted great attention from researchers, scientists, photovoltaic (PV) industry engineers for the past few decades. With thin wafers, surface passivation becomes necessary to increase the solar cells efficiency by overcoming several induced effects due to associated crystal defects and impurities of c-Si. This paper discusses suitable passivation schemes and optimization techniques to achieve high efficiency at low cost. SiNx film was optimized with higher transmittance and reduced recombination for using as an effective antireflection and passivation layer to attain higher solar cell efficiencies. The higher band gap increased the transmittance with reduced defect states that persisted at 1.68 and 1.80 eV in SiNx films. The thermal stability of SiN (Si-rich)/SiN (N-rich) stacks was also studied. Si-rich SiN with a refractive index of 2.7 was used as a passivation layer and N-rich SiN with a refractive index of 2.1 was used for thermal stability. An implied Voc of 720 mV with a stable lifetime of 1.5 ms was obtained for the stack layer after firing. Si-N and Si-H bonding concentration was analyzed by FTIR for the correlation of thermally stable passivation mechanism. The passivation property of spin coated Al2O3 films was also investigated. An effective surface recombination velocity of 55 cm/s with a high density of negative fixed charges (Qf) on the order of 9 x 10(11) cm(-2) was detected in Al2O3 films.

  1. Advanced Scintillator-Based Compton Telescope for Solar Flare Gamma-Ray Measurements

    NASA Astrophysics Data System (ADS)

    Ryan, James Michael; Bloser, Peter; McConnell, Mark; Legere, Jason; Bancroft, Christopher; Murphy, Ronald; de Nolfo, Georgia

    2015-04-01

    A major goal of future Solar and Heliospheric Physics missions is the understanding of the particle acceleration processes taking place on the Sun. Achieving this understanding will require detailed study of the gamma-ray emission lines generated by accelerated ions in solar flares. Specifically, it will be necessary to study gamma-ray line ratios over a wide range of flare intensities, down to small C-class flares. Making such measurements over such a wide dynamic range, however, is a serious challenge to gamma-ray instrumentation, which must deal with large backgrounds for faint flares and huge counting rates for bright flares. A fast scintillator-based Compton telescope is a promising solution to this instrumentation challenge. The sensitivity of Compton telescopes to solar flare gamma rays has already been demonstrated by COMPTEL, which was able to detect nuclear emission from a C4 flare, the faintest such detection to date. Modern fast scintillators, such as LaBr3, and CeBr3, are efficient at stopping MeV gamma rays, have sufficient energy resolution (4% or better above 0.5 MeV) to resolve nuclear lines, and are fast enough (~15 ns decay times) to record at very high rates. When configured as a Compton telescope in combination with a modern organic scintillator, such as p-terphenyl, sub-nanosecond coincidence resolving time allows dramatic suppression of background via time-of-flight (ToF) measurements, allowing both faint and bright gamma-ray line flares to be measured. The use of modern light readout devices, such as silicon photomultipliers (SiPMs), eliminates passive mass and permits a more compact, efficient instrument. We have flown a prototype Compton telescope using modern fast scintillators with SiPM readouts on a balloon test flight, achieving good ToF and spectroscopy performance. A larger balloon-borne instrument is currently in development. We present our test results and estimates of the solar flare sensitivity of a possible full-scale instrument

  2. A program continuation to develop processing procedures for advanced silicon solar cells

    NASA Technical Reports Server (NTRS)

    Avery, J. E.; Scott-Monck, J. A.

    1976-01-01

    Shallow junctions, aluminum back surface fields and tantalum pentoxide (Ta205) antireflection coatings coupled with the development of a chromium-palladium-silver contact system, were used to produce a 2 x 4 cm wraparound contact silicon solar cell. One thousand cells were successfully fabricated using batch processing techniques. These cells were 0.020 mm thick, with the majority (800) made from nominal ten ohm-cm silicon and the remainder from nominal 30 ohm-cm material. Unfiltered, these cells delivered a minimum AMO efficiency at 25 C of 11.5 percent and successfully passed all the normal in-process and acceptance tests required for space flight cells.

  3. Advances in thin-film solar cells for lightweight space photovoltaic power

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Bailey, Sheila G.; Flood, Dennis J.

    1989-01-01

    The development of photovoltaic arrays beyond the next generation is discussed with attention given to the potentials of thin-film polycrystalline and amorphous cells. Of particular importance is the efficiency (the fraction of incident solar energy converted to electricity) and specific power (power to weight ratio). It is found that the radiation tolerance of thin-film materials is far greater than that of single crystal materials. CuInSe2 shows no degradation when exposed to 1-MeV electrons.

  4. METSAT information content: Cloud screening and solar correction investigations on the influence of NOAA-6 advanced very high resolution radiometer derived vegetation assessment

    NASA Technical Reports Server (NTRS)

    Mathews, M. L.

    1983-01-01

    The development of the cloud indicator index (CII) for use with METSAT's advanced very high resolution radiometer (AVHRR) is described. The CII is very effective at identification of clouds. Also, explored are different solar correction and standard techniques and the impact of these corrections have on the information content of AVHRR data.

  5. Coordination of Advanced Solar Observatory (ASO) Science Working Group (SWG) for the study of instrument accommodation and operational requirements on space station

    NASA Technical Reports Server (NTRS)

    Wu, S. T.

    1989-01-01

    The objectives are to coordinate the activities of the Science Working Group (SWG) of the Advanced Solar Observatory (ASO) for the study of instruments accommodation and operation requirements on board space station. In order to facilitate the progress of the objective, two conferences were organized, together with two small group discussions.

  6. On the Path to SunShot - Advancing Concentrating Solar Power Technology, Performance, and Dispatchability

    SciTech Connect

    Mehos, Mark; Turchi, Craig; Jorgenson, Jennie; Denholm, Paul; Ho, Clifford; Armijo, Kenneth

    2016-05-01

    Energy storage will help enable CSP compete by adding flexibility value to a high-variable-generation (solar plus wind) power system (see Mehos et al. 2016). Compared with PV, CSP systems are more complex to develop, design, construct, and operate, and they require a much larger minimum effective scale—typically at least 50 MW, compared with PV systems that can be as small as a few kilowatts. In recent years, PV’s greater modularity and lower LCOE have made it more attractive to many solar project developers, and some large projects that were originally planned for CSP have switched to PV. However, the ability of CSP to use thermal energy storage—and thus provide continuous power for long periods when the sun is not shining—could give CSP a vital role in evolving electricity systems. Because CSP with storage can store energy when net demand is low and release that energy when demand is high, it increases the electricity system’s ability to balance supply and demand over multiple time scales. Such flexibility becomes increasingly important as more variable-generation renewable energy is added to the system. For example, one analysis suggests that, under a 40% renewable portfolio standard in California, CSP with storage could provide more than twice as much value to the electricity system as variable-generation PV. For this reason, enhanced thermal energy storage is a critical component of the SunShot Initiative’s 2020 CSP technology-improvement roadmap.

  7. Advancement of a 30K W Solar Electric Propulsion System Capability for NASA Human and Robotic Exploration Missions

    NASA Technical Reports Server (NTRS)

    Smith, Bryan K.; Nazario, Margaret L.; Manzella, David H.

    2012-01-01

    Solar Electric Propulsion has evolved into a demonstrated operational capability performing station keeping for geosynchronous satellites, enabling challenging deep-space science missions, and assisting in the transfer of satellites from an elliptical orbit Geostationary Transfer Orbit (GTO) to a Geostationary Earth Orbit (GEO). Advancing higher power SEP systems will enable numerous future applications for human, robotic, and commercial missions. These missions are enabled by either the increased performance of the SEP system or by the cost reductions when compared to conventional chemical propulsion systems. Higher power SEP systems that provide very high payload for robotic missions also trade favorably for the advancement of human exploration beyond low Earth orbit. Demonstrated reliable systems are required for human space flight and due to their successful present day widespread use and inherent high reliability, SEP systems have progressively become a viable entrant into these future human exploration architectures. NASA studies have identified a 30 kW-class SEP capability as the next appropriate evolutionary step, applicable to wide range of both human and robotic missions. This paper describes the planning options, mission applications, and technology investments for representative 30kW-class SEP mission concepts under consideration by NASA

  8. Tracking the Sun IX: The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States

    SciTech Connect

    Barbose, Galen; Darghouth, Naïm; Millstein, Dev; Cates, Sarah; DiSanti, Nicholas; Widiss, Rebecca

    2016-08-16

    Now in its ninth edition, Lawrence Berkeley National Laboratory (LBNL)’s Tracking the Sun report series is dedicated to summarizing trends in the installed price of grid-connected solar photovoltaic (PV) systems in the United States. The present report focuses on residential and non-residential systems installed through year-end 2015, with preliminary trends for the first half of 2016. An accompanying LBNL report, Utility-Scale Solar, addresses trends in the utility-scale sector. This year’s report incorporates a number of important changes and enhancements from prior editions. Among those changes, LBNL has made available a public data file containing all non-confidential project-level data underlying the analysis in this report. Installed pricing trends presented within this report derive primarily from project-level data reported to state agencies and utilities that administer PV incentive programs, solar renewable energy credit (SREC) registration systems, or interconnection processes. Refer to the text box to the right for several key notes about these data. In total, data were collected and cleaned for more than 820,000 individual PV systems, representing 85% of U.S. residential and non-residential PV systems installed cumulatively through 2015 and 82% of systems installed in 2015. The analysis in this report is based on a subset of this sample, consisting of roughly 450,000 systems with available installed price data.

  9. Tracking the Sun VIII. The Installed Price of Residential and Non-Residential Photovoltaic Systems in the United States

    SciTech Connect

    Barbose, Galen L.; Darghouth, Naïm R.; Millstein, Dev; Spears, Mike; Wiser, Ryan H.; Buckley, Michael; Widiss, Rebecca; Grue, Nick

    2015-08-01

    Now in its eighth edition, Lawrence Berkeley National Laboratory (LBNL)’s Tracking the Sun report series is dedicated to summarizing trends in the installed price of grid-connected solar photovoltaic (PV) systems in the United States. The present report focuses on residential and nonresidential systems installed through year-end 2014, with preliminary trends for the first half of 2015. As noted in the text box below, this year’s report incorporates a number of important changes and enhancements. Among those changes, this year's report focuses solely on residential and nonresidential PV systems; data on utility-scale PV are reported in LBNL’s companion Utility-Scale Solar report series. Installed pricing trends presented within this report derive primarily from project-level data reported to state agencies and utilities that administer PV incentive programs, solar renewable energy credit (SREC) registration systems, or interconnection processes. In total, data were collected for roughly 400,000 individual PV systems, representing 81% of all U.S. residential and non-residential PV capacity installed through 2014 and 62% of capacity installed in 2014, though a smaller subset of this data were used in analysis.

  10. Anomalously high lifetimes measured by quasi-steady-state photoconductance in advanced solar cell structures

    NASA Astrophysics Data System (ADS)

    Juhl, Mattias; Chan, Catherine; Abbott, Malcolm D.; Trupke, Thorsten

    2013-12-01

    Quasi-Steady-State Photoconductance is widely used in photovoltaics industry to measure the effective minority carrier lifetime of silicon wafers, a key material parameter affecting final solar cell efficiency. When interpreting photoconductance based lifetime measurements, it is important to account for various artefacts that can cause an over-estimation of the carrier lifetime, such as minority carrier trapping. This paper provides experimental evidence for another artefact in photoconductance lifetime measurements, affecting samples that have a conductive layer that is interrupted by lines of the opposite polarity doping, forming laterally alternating regions of p/n doping. This structure often appears in the emitter region of samples used to monitor the lifetime of interdigitated back contact cells. The cause of this artefact is linked to a reduction in the measured dark conductance. Experimental data are presented that suggest this is due to the formation of a phototransistor type structure on the samples surface, resulting in variations in conductivity under different illumination levels.

  11. Study of advanced radial outflow turbine for solar steam Rankine engines

    NASA Technical Reports Server (NTRS)

    Martin, C.; Kolenc, T.

    1979-01-01

    The performance characteristics of various steam Rankine engine configurations for solar electric power generation were investigated. A radial outflow steam turbine was investigated to determine: (1) a method for predicting performance from experimental data; (2) the flexibility of a single design with regard to power output and pressure ratio; and (3) the effect of varying the number of turbine stages. All turbine designs were restricted to be compatible with commercially available gearboxes and generators. A study of several operating methods and control schemes for the steam Rankine engine shows that from an efficiency and control simplicity standpoint, the best approach is to hold turbine inlet temperature constant, vary turbine inlet pressure to match load, and allow condenser temperature to float maintaining constant heat rejection load.

  12. Advanced Heat/Mass Exchanger Technology for Geothermal and Solar Renewable Energy Systems

    SciTech Connect

    Greiner, Miles; Childress, Amy; Hiibel, Sage; Kim, Kwang; Park, Chanwoo; Wirtz, Richard

    2014-12-16

    Northern Nevada has abundant geothermal and solar energy resources, and these renewable energy sources provide an ample opportunity to produce economically viable power. Heat/mass exchangers are essential components to any energy conversion system. Improvements in the heat/mass exchange process will lead to smaller, less costly (more efficient) systems. There is an emerging heat transfer technology, based on micro/nano/molecular-scale surface science that can be applied to heat/mass exchanger design. The objective is to develop and characterize unique coating materials, surface configurations and membranes capable of accommodating a 10-fold increase in heat/mass exchanger performance via phase change processes (boiling, condensation, etc.) and single phase convective heat/mass transfer.

  13. Large-Scale Residential Demolition

    EPA Pesticide Factsheets

    The EPA provides resources for handling residential demolitions or renovations. This includes planning, handling harmful materials, recycling, funding, compliance assistance, good practices and regulations.

  14. Re-thinking residential mobility

    PubMed Central

    van Ham, Maarten; Findlay, Allan M.

    2015-01-01

    While researchers are increasingly re-conceptualizing international migration, far less attention has been devoted to re-thinking short-distance residential mobility and immobility. In this paper we harness the life course approach to propose a new conceptual framework for residential mobility research. We contend that residential mobility and immobility should be re-conceptualized as relational practices that link lives through time and space while connecting people to structural conditions. Re-thinking and re-assessing residential mobility by exploiting new developments in longitudinal analysis will allow geographers to understand, critique and address pressing societal challenges. PMID:27330243

  15. Effects of flux emergence in the outer solar atmosphere. Observational advances

    NASA Astrophysics Data System (ADS)

    Ortiz Carbonell, Ada; De Pontieu, Bart; Bellot Rubio, L. R.; Hansteen, Viggo; Rouppe van der Voort, Luc; Carlsson, Mats

    We study granular sized magnetic flux emergence events that occur in a flux emergence region in NOAA 11850 on September 25, 2013. During that time, the first co-observing campaign between the Swedish 1 m Solar Telescope and the IRIS spacecraft was carried out. Simultaneous observations of the Halpha 656.28 nm and Ca II 854.2 nm chromospheric lines, and the Fe I 630.25 nm photospheric line, were made with the CRISP/SST spectropolarimeter reaching a spatial resolution of 0."14. At the same time, IRIS was performing a four-step dense raster of the said emerging flux region, taking slit-jaw images at 133 (C II transiti on region), 140 (Si IV, transition region), 279.6 (Mg II k, core, upper chromosphere), and 283.2 nm (Mg II k, wing, photosphere), obtaining thus the highest resolution images ever taken of the upper chromosphere and transition region. The photospheric and chromospheric properties of the emerging magnetic flux bubbles have been described in detail in Ortiz et al. (2014). However, in the current work we are able to follow such lower atmosphere observations of flux emergence up to the transition region with unprecedented spatial and temporal resolution. We describe the properties (size, time delays, lifetime, velocities, temperature) of the observed signatures of flux emergence in the transition region. We believe this may be an important mechanism of transporting energy and magnetic flux to the upper layers of the solar atmosphere, namely the transition region and corona, at least in cases when active regions are formed by flux emerging through the photosphere. * Ortiz et al. (2014) ApJ 781, 126

  16. Advanced Methods for Incorporating Solar Energy Technologies into Electric Sector Capacity-Expansion Models: Literature Review and Analysis

    SciTech Connect

    Sullivan, P.; Eurek, K.; Margolis, R.

    2014-07-01

    Because solar power is a rapidly growing component of the electricity system, robust representations of solar technologies should be included in capacity-expansion models. This is a challenge because modeling the electricity system--and, in particular, modeling solar integration within that system--is a complex endeavor. This report highlights the major challenges of incorporating solar technologies into capacity-expansion models and shows examples of how specific models address those challenges. These challenges include modeling non-dispatchable technologies, determining which solar technologies to model, choosing a spatial resolution, incorporating a solar resource assessment, and accounting for solar generation variability and uncertainty.

  17. Nanostructured Solar Cells.

    PubMed

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-08-09

    We are glad to announce the Special Issue "Nanostructured Solar Cells", published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  18. Nanostructured Solar Cells

    PubMed Central

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-01-01

    We are glad to announce the Special Issue “Nanostructured Solar Cells”, published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  19. ASHRAE and residential ventilation

    SciTech Connect

    Sherman, Max H.

    2003-10-01

    In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is the

  20. Recent Advances of Cobalt(II/III) Redox Couples for Dye-Sensitized Solar Cell Applications.

    PubMed

    Giribabu, Lingamallu; Bolligarla, Ramababu; Panigrahi, Mallika

    2015-08-01

    In recent years dye-sensitized solar cells (DSSCs) have emerged as one of the alternatives for the global energy crisis. DSSCs have achieved a certified efficiency of >11% by using the I(-) /I3 (-) redox couple. In order to commercialize the technology almost all components of the device have to be improved. Among the various components of DSSCs, the redox couple that regenerates the oxidized sensitizer plays a crucial role in achieving high efficiency and durability of the cell. However, the I(-) /I3 (-) redox couple has certain limitations such as the absorption of triiodide up to 430 nm and the volatile nature of iodine, which also corrodes the silver-based current collectors. These limitations are obstructing the commercialization of this technology. For this reason, one has to identify alternative redox couples. In this regard, the Co(II/III) redox couple is found to be the best alternative to the existing I(-) /I3 (-) redox couple. Recently, DSSC test cell efficiency has risen up to 13% by using the cobalt redox couple. This review emphasizes the recent development of Co(II/III) redox couples for DSSC applications.

  1. Advances on multijunction solar cell characterization aimed at the optimization of real concentrator performance

    SciTech Connect

    Garcia-Linares, Pablo Dominguez, César Voarino, Philippe Besson, Pierre Baudrit, Mathieu

    2014-09-26

    Multijunction solar cells (MJSC) are usually developed to maximize efficiency under test conditions and not under real operation. This is the case of anti-reflective coatings (ARC), which are meant to minimize Fresnel reflection losses for a family of incident rays at room temperature. In order to understand and quantify the discrepancies between test and operation conditions, we have experimentally analyzed the spectral response of MJSC for a variety of incidence angles that are in practice received by a concentrator cell in high-concentration photovoltaic (HCPV) receiver designs. Moreover, we characterize this angular dependence as a function of temperature in order to reproduce real operation conditions. As the refractive index of the silicone is dependent on temperature, an optical mismatch is expected. Regarding other characterization techniques, a method called Relative EL Homogeneity Analysis (RELHA) is applied to processed wafers prior to dicing, allowing to diagnose the wafer crystalline homogeneity for each junction. Finally, current (I)-voltage (V) characterization under strongly unbalanced light spectra has also been carried out for a number of low-level irradiances, providing insight on each junction shunt resistance and corresponding radiative coupling.

  2. New advances in protection against solar ultraviolet radiation in textiles for summer clothing.

    PubMed

    Aguilera, José; de Gálvez, María Victoria; Sánchez-Roldán, Cristina; Herrera-Ceballos, Enrique

    2014-01-01

    Clothing is considered one of the most important tools for photoprotection against harmful solar ultraviolet radiation (UVR). The standard for sun-protective clothing is based on erythema despite other biological effects of UVR on the skin. We analyzed the potential protection against UVR in fabrics destined for summer clothing based on several action spectra. We examined 50 garments classified by type of fabric composition, structure of the fiber yarn and color. The ultraviolet protection factor was calculated based on fabric ultraviolet transmittance corrected for erythema according to the EU standard E-13758 as well as the UVA transmittance of fabrics. UVR protection was also analyzed in base of different action spectra as for previtamin D3, nonmelanoma skin cancer, photoimmunosuppression and photoaging. Most knitted fabrics used for sports T-shirts offered excellent ratings for ultraviolet protection while normal shirts showed very low ratings, particularly against photoaging. The cover is the most influential variable in fabric photoprotection, having an exponential relationship with the UPF. The relation between cover and UVA protection was linearly negative. Information about ultraviolet protection in textiles used for summer clothing should be included in labeling as some types of fabrics, especially those used for shirts, offer very low UVR protection.

  3. Advances in all-sputtered CdTe solar cells on flexible substrates

    NASA Astrophysics Data System (ADS)

    Wieland, Kristopher; Mahabaduge, Hasitha; Vasko, Anthony; Compaan, Alvin

    2010-03-01

    The University of Toledo II-VI semiconductor group has developed magnetron sputtering (MS) for the deposition of thin films of CdS, CdTe, and related materials for photovoltaic applications. On glass superstrates, we have reached air mass 1.5 efficiencies of 14%.[1] Recently we have studied the use of MS for the fabrication of thin-film CdS/CdTe cells on flexible polyimide superstrates. This takes advantage of the high film quality that can be achieved at substrate temperatures below 300 C when RF MS is used. Our recent CdS/CdTe solar cells have reached 10.5% on flexible polyimide substrates. [2] This all-sputtered cell (except for back contact) has a structure of polyimide/ZnO:Al/ZnO/CdS/CdTe/Cu/Au. The physics of this device will be discussed through the use of spectral quantum efficiency and current-voltage measurements as a function of CdTe layer thickness. Pathways toward further increases in device efficiencies will also be discussed. [1] Appl. Phys. Lett. 85, 684 (2004) [2] Phys. Stat. Sol. (B) 241, No. 3, 779--782 (2004)

  4. Comparison of advanced thermal and electrical storage for parabolic dish solar thermal power systems

    NASA Technical Reports Server (NTRS)

    Fujita, T.; Birur, G. C.; Schredder, J. M.; Bowyer, J. M.; Awaya, H. I.

    1982-01-01

    Parabolic dish solar concentrator cluster concepts are explored, with attention given to thermal storage systems coupled to Stirling and Brayton cycle power conversion devices. Sensible heat storage involving molten salt (NaOH), liquid sodium, and solid cordierite bricks are considered for 1500 F thermal storage systems. Latent heat storage with NaF-MgF2 phase change materials are explored in terms of passive, active, and direct contact designs. Comparisons are made of the effectiveness of thermal storage relative to redox, Na-S, Zn-Cl, and Zn-Br battery storage systems. Molten lead trickling down through a phase change eutectic, the NaF-MgF2, formed the direct contact system. Heat transport in all systems is effected through Inconel pipes. Using a cost goal of 120-150 mills/kWh as the controlling parameter, sensible heat systems with molten salts transport with either Stirling or Brayton engines, or latent heat systems with Stirling engines, and latent heat-Brayton engine with direct contact were favored in the analyses. Battery storage systems, however, offered the most flexibility of applications.

  5. Comparison of advanced thermal and electrical storage for parabolic dish solar thermal power systems

    NASA Astrophysics Data System (ADS)

    Fujita, T.; Birur, G. C.; Schredder, J. M.; Bowyer, J. M.; Awaya, H. I.

    Parabolic dish solar concentrator cluster concepts are explored, with attention given to thermal storage systems coupled to Stirling and Brayton cycle power conversion devices. Sensible heat storage involving molten salt (NaOH), liquid sodium, and solid cordierite bricks are considered for 1500 F thermal storage systems. Latent heat storage with NaF-MgF2 phase change materials are explored in terms of passive, active, and direct contact designs. Comparisons are made of the effectiveness of thermal storage relative to redox, Na-S, Zn-Cl, and Zn-Br battery storage systems. Molten lead trickling down through a phase change eutectic, the NaF-MgF2, formed the direct contact system. Heat transport in all systems is effected through Inconel pipes. Using a cost goal of 120-150 mills/kWh as the controlling parameter, sensible heat systems with molten salts transport with either Stirling or Brayton engines, or latent heat systems with Stirling engines, and latent heat-Brayton engine with direct contact were favored in the analyses. Battery storage systems, however, offered the most flexibility of applications.

  6. Educational Attainment and Residential Location

    ERIC Educational Resources Information Center

    Sander, William

    2006-01-01

    The effects of residential location at age 16 and current residential location on measures of educational attainment are estimated. Particular attention is given to the effects of migration and family background on educational outcomes. It is shown that central cities and suburbs of large metropolitan areas in the United States have significantly…

  7. Education Funding for Residential Facilities.

    ERIC Educational Resources Information Center

    Ohio State Legislative Office of Education Oversight, Columbus.

    About 167 residential facilities in Ohio serve approximately 7,000 youth on any given day. Youth are placed in residential facilities because they have committed a crime or have behavioral problems. An "education provider" operates an on-grounds school in most facilities. Because of ongoing concerns about education funding for youth in…

  8. Advanced controls for stability assessment of solar dynamics space power generation

    NASA Astrophysics Data System (ADS)

    Momoh, James A.; Anwah, Nnamdi A.

    1995-08-01

    In support of the power requirements for the Space Station Alpha (SSA), a joint program by the U.S. and Russia for a permanently manned space station to be launched into orbit by 1998, a robust control scheme is needed to assure the stability of the rotating machines that will be integrated into the power subsystem. A framework design and systems studies for modeling and analysis is presented. It employs classical d-q axes machine model with voltage/frequency dependent loads. To guarantee that design requirements and necessary trade studies are done, a functional analysis tool CORE is used for the study. This provides us with different control options for stability assessment. Initial studies and recommendations using advanced simulation tools are also presented. The benefits of the stability/control scheme for evaluating future designs and power management are discussed.

  9. Advanced MHD Algorithm for Solar and Space Science: lst Year Semi Annual Progress Report

    NASA Technical Reports Server (NTRS)

    Schnack, Dalton D.; Lionello, Roberto

    2003-01-01

    We report progress for the development of MH4D for the first and second quarters of FY2004, December 29, 2002 - June 6, 2003. The present version of MH4D can now solve the full viscous and resistive MHD equations using either an explicit or a semi-implicit time advancement algorithm. In this report we describe progress in the following areas. During the two last quarters we have presented poster at the EGS-AGU-EUG Joint Assembly in Nice, France, April 6-11, 2003, and a poster at the 2003 International Sherwood Theory Conference in Corpus Christi, Texas, April 28-30 2003. In the area of code development, we have implemented the MHD equations and the semi-implicit algorithm. The new features have been tested.

  10. Advanced controls for stability assessment of solar dynamics space power generation

    NASA Technical Reports Server (NTRS)

    Momoh, James A.; Anwah, Nnamdi A.

    1995-01-01

    In support of the power requirements for the Space Station Alpha (SSA), a joint program by the U.S. and Russia for a permanently manned space station to be launched into orbit by 1998, a robust control scheme is needed to assure the stability of the rotating machines that will be integrated into the power subsystem. A framework design and systems studies for modeling and analysis is presented. It employs classical d-q axes machine model with voltage/frequency dependent loads. To guarantee that design requirements and necessary trade studies are done, a functional analysis tool CORE is used for the study. This provides us with different control options for stability assessment. Initial studies and recommendations using advanced simulation tools are also presented. The benefits of the stability/control scheme for evaluating future designs and power management are discussed.

  11. ASSESSMENT OF THE EFFECTS OF WEATHERIZATION ON RESIDENTIAL RADON LEVELS

    EPA Science Inventory

    The report gives results of an assessment of the effects of weatherization on residential radon levels. For this assessment, time-integrated radon measurements were taken for 30- to 45-day periods both before and after weatherization in 32 Retro-Tech homes, 28 advanced homes, and...

  12. Solar/gas Rankine/Rankine-cycle heat pump assessment

    NASA Astrophysics Data System (ADS)

    Khalifa, H. E.; Melikian, G.

    1982-07-01

    This report contains an assessment of the technical and economic feasibility of Rankine-cycle solar-augmented gas-fired heat pumps (SAGFHP) for multi-family residential and light-commercial applications. The SAGFHP design considered in this report is based on the successful UTRC turbocompressor system which has been tested both in the laboratory and in a solar cooling installation in Phoenix. AZ. An hour-by-hour modeling of present-design SAGFHP performance in multi-family and office buildings in New York, Wisconsin, Nebraska and Oregon indicated that, even without solar augmentation, primary energy savings of up 17% and 31% could be achieved relative to advanced furnace plus electric air conditioning systems and electric heat pumps, respectively.

  13. Residential Mechanical Precooling

    SciTech Connect

    German, Alea; Hoeschele, Marc

    2014-12-01

    Residential air conditioning (AC) represents a challenging load for many electric utilities with poor load factors. Mechanical precooling improves the load factor by shifting cooling operation from on-peak to off-peak hours. This provides benefits to utilities and the electricity grid, as well as to occupants who can take advantage of time-of-use (TOU) electricity rates. Performance benefits stem from reduced compressor cycling, and shifting condensing unit operation to earlier periods of the day when outdoor temperatures are more favorable to operational efficiency. Finding solutions that save energy and reduce demand on the electricity grid is an important national objective and supports key Building America goals. The Alliance for Residential Building Innovation team evaluated mechanical AC precooling strategies in homes throughout the United States. EnergyPlus modeling was used to evaluate two homes with different performance characteristics in seven climates. Results are applicable to new construction homes and most existing homes built in the last 10 years, as well as fairly efficient retrofitted homes. A successful off-peak AC strategy offers the potential for increased efficiency and improved occupant comfort, and promotes a more reliable and robust electricity grid. Demand response capabilities and further integration with photovoltaic TOU generation patterns provide additional opportunities to flatten loads and optimize grid impacts.

  14. Residential fuel quality

    SciTech Connect

    Santa, T.

    1997-09-01

    This report details progress made in improving the performance of No. 2 heating oil in residential applications. Previous research in this area is documented in papers published in the Brookhaven Oil Heat Technology Conference Proceedings in 1993, 1994 and 1996. By way of review we have investigated a number of variables in the search for improved fuel system performance. These include the effect of various additives designed to address stability, dispersion, biotics, corrosion and reaction with metals. We have also investigated delivery methods, filtration, piping arrangements and the influence of storage tank size and location. As a result of this work Santa Fuel Inc. in conjunction with Mobile Oil Corporation have identified an additive package which shows strong evidence of dramatically reducing the occurrence of fuel system failures in residential oil burners. In a broad market roll-out of the additized product we have experienced a 29% reduction in fuel related service calls when comparing the 5 months ending January 1997 to the same period ending January 1996.

  15. Strategy Guideline. High Performance Residential Lighting

    SciTech Connect

    Holton, J.

    2012-02-01

    This report has been developed to provide a tool for the understanding and application of high performance lighting in the home. The strategies featured in this guide are drawn from recent advances in commercial lighting for application to typical spaces found in residential buildings. This guide offers strategies to greatly reduce lighting energy use through the application of high quality fluorescent and light emitting diode (LED) technologies. It is important to note that these strategies not only save energy in the home but also serve to satisfy the homeowner’s expectations for high quality lighting.

  16. Solar Innovator | Alta Devices

    ScienceCinema

    Mattos, Laila; Le, Minh

    2016-07-12

    Selected to participate in the Energy Department's SunShot Initiative, Alta Devices produces solar cells that convert sunlight into electricity at world record-breaking levels of efficiency. Through its innovative solar technology Alta is helping bring down the cost of solar. Learn more about the Energy Department's efforts to advance solar technology at energy.gov/solar .

  17. Solar Innovator | Alta Devices

    SciTech Connect

    Mattos, Laila; Le, Minh

    2012-01-01

    Selected to participate in the Energy Department's SunShot Initiative, Alta Devices produces solar cells that convert sunlight into electricity at world record-breaking levels of efficiency. Through its innovative solar technology Alta is helping bring down the cost of solar. Learn more about the Energy Department's efforts to advance solar technology at energy.gov/solar .

  18. On the Path to SunShot. Advancing Concentrating Solar Power Technology, Performance, and Dispatchability

    SciTech Connect

    Mehos, Mark; Turchi, Craig; Jorgenson, Jennie; Denholm, Paul; Ho, Clifford; Armijo, Kenneth

    2016-05-01

    This report examines the remaining challenges to achieving the competitive concentrating solar power (CSP) costs and large-scale deployment envisioned under the U.S. Department of Energy's SunShot Initiative. Although CSP costs continue to decline toward SunShot targets, CSP acceptance and deployment have been hindered by inexpensive photovoltaics (PV). However, a recent analysis found that thermal energy storage (TES) could increase CSP's value--based on combined operational and capacity benefits--by up to 6 cents/kWh compared to variable-generation PV, under a 40% renewable portfolio standard in California. Thus, the high grid value of CSP-TES must be considered when evaluating renewable energy options. An assessment of net system cost accounts for the difference between the costs of adding new generation and the avoided cost from displacing other resources providing the same level of energy and reliability. The net system costs of several CSP configurations are compared with the net system costs of conventional natural-gas-fired combustion-turbine (CT) and combined-cycle plants. At today's low natural gas prices and carbon emission costs, the economics suggest a peaking configuration for CSP. However, with high natural gas prices and emission costs, each of the CSP configurations compares favorably against the conventional alternatives, and systems with intermediate to high capacity factors become the preferred alternatives. Another analysis compares net system costs for three configurations of CSP versus PV with batteries and PV with CTs. Under current technology costs, the least-expensive option is a combination of PV and CTs. However, under future cost assumptions, the optimal configuration of CSP becomes the most cost-effective option.

  19. National Residential Efficiency Measures Database

    DOE Data Explorer

    The National Residential Efficiency Measures Database is a publicly available, centralized resource of residential building retrofit measures and costs for the U.S. building industry. With support from the U.S. Department of Energy, NREL developed this tool to help users determine the most cost-effective retrofit measures for improving energy efficiency of existing homes. Software developers who require residential retrofit performance and cost data for applications that evaluate residential efficiency measures are the primary audience for this database. In addition, home performance contractors and manufacturers of residential materials and equipment may find this information useful. The database offers the following types of retrofit measures: 1) Appliances, 2) Domestic Hot Water, 3) Enclosure, 4) Heating, Ventilating, and Air Conditioning (HVAC), 5) Lighting, 6) Miscellaneous.

  20. Solar ADEPT: Efficient Solar Energy Systems

    SciTech Connect

    2011-01-01

    Solar ADEPT Project: The 7 projects that make up ARPA-E's Solar ADEPT program, short for 'Solar Agile Delivery of Electrical Power Technology,' aim to improve the performance of photovoltaic (PV) solar energy systems, which convert the sun's rays into electricity. Solar ADEPT projects are integrating advanced electrical components into PV systems to make the process of converting solar energy to electricity more efficient.

  1. Photovoltaic solar array technology required for three wide scale generating systems for terrestrial applications: rooftop, solar farm, and satellite

    NASA Technical Reports Server (NTRS)

    Berman, P. A.

    1972-01-01

    Three major options for wide-scale generation of photovoltaic energy for terrestrial use are considered: (1) rooftop array, (2) solar farm, and (3) satellite station. The rooftop array would use solar cell arrays on the roofs of residential or commercial buildings; the solar farm would consist of large ground-based arrays, probably in arid areas with high insolation; and the satellite station would consist of an orbiting solar array, many square kilometers in area. The technology advancement requirements necessary for each option are discussed, including cost reduction of solar cells and arrays, weight reduction, resistance to environmental factors, reliability, and fabrication capability, including the availability of raw materials. The majority of the technology advancement requirements are applicable to all three options, making possible a flexible basic approach regardless of the options that may eventually be chosen. No conclusions are drawn as to which option is most advantageous, since the feasibility of each option depends on the success achieved in the technology advancement requirements specified.

  2. Autonomous space processor for orbital debris advanced design project in support of solar system exploration

    NASA Astrophysics Data System (ADS)

    Ramohalli, Kumar; Mitchell, Dominique; Taft, Brett; Chinnock, Paul; Kutz, Bjoern

    This paper is regarding a project in the Advanced Design Program at the University of Arizona. The project is named the Autonomous Space Processor for Orbital Debris (ASPOD) and is a NASA/Universities Space Research Association (USRA) sponsored design project. The development of ASPOD and the students' abilities in designing and building a prototype spacecraft are the ultimate goals of this project. This year's focus entailed the development of a secondary robotic arm and end-effector to work in tandem with an existent arm in the removal of orbital debris. The new arm features the introduction of composite materials and a linear drive system, thus producing a light-weight and more accurate prototype. The main characteristic of the end-effector design is that it incorporates all of the motors and gearing internally, thus not subjecting them to the harsh space environment. Furthermore, the arm and the end-effector are automated by a control system with positional feedback. This system is composed of magnetic and optical encoders connected to a 486 PC via two servo-motor controller cards. Programming a series of basic routines and sub-routines has allowed the ASPOD prototype to become more autonomous. The new system is expected to perform specified tasks with a positional accuracy of 0.5 cm.

  3. Autonomous space processor for orbital debris advanced design project in support of solar system exploration

    NASA Technical Reports Server (NTRS)

    Ramohalli, Kumar; Mitchell, Dominique; Taft, Brett; Chinnock, Paul; Kutz, Bjoern

    1992-01-01

    This paper is regarding a project in the Advanced Design Program at the University of Arizona. The project is named the Autonomous Space Processor for Orbital Debris (ASPOD) and is a NASA/Universities Space Research Association (USRA) sponsored design project. The development of ASPOD and the students' abilities in designing and building a prototype spacecraft are the ultimate goals of this project. This year's focus entailed the development of a secondary robotic arm and end-effector to work in tandem with an existent arm in the removal of orbital debris. The new arm features the introduction of composite materials and a linear drive system, thus producing a light-weight and more accurate prototype. The main characteristic of the end-effector design is that it incorporates all of the motors and gearing internally, thus not subjecting them to the harsh space environment. Furthermore, the arm and the end-effector are automated by a control system with positional feedback. This system is composed of magnetic and optical encoders connected to a 486 PC via two servo-motor controller cards. Programming a series of basic routines and sub-routines has allowed the ASPOD prototype to become more autonomous. The new system is expected to perform specified tasks with a positional accuracy of 0.5 cm.

  4. Conceptual design of an advanced water/steam central solar receiver, volume 1

    NASA Astrophysics Data System (ADS)

    Matthews, F. T.; Payne, H. M.; Jones, B. O.; Snyder, T. K.; Davidson, M. J.

    1980-06-01

    A drum type boiler with forced circulation evaporator using rifled tubing can be designed for the high heat flux of a North field collector without the problems associated with departure of nuclear boiling. Existing boiler technology and materials can be used to design an advanced water/steam receiver. Rifled tubing was shown by test data to provide protection to evaporator panels at peak heat flux levels 30 percent greater than the design point of these receivers. Estimated budgetary type costs of these receivers vary from $10 per pound of steam for the large receiver to $13 per pound of steam for the smaller units. Fatigue life was conservatively calculated to be 30,000 full strain range cycles. This is adequate for the diurnal cycling, plus some cloud over a 30 year period. It is possible that the allowable creep fatigue cycles may be increased to 40,000 - 50,000 by an inelastic stress analysis. This analysis was recommended for future work and is required to resolve the cyclic lifetime of these receivers. Additional analysis is also needed to resolve receiver and plant control systems.

  5. Energy Savings Potential and Opportunities for High-Efficiency Electric Motors in Residential and Commercial Equipment

    SciTech Connect

    Goetzler, William; Sutherland, Timothy; Reis, Callie

    2013-12-04

    This report describes the current state of motor technology and estimates opportunities for energy savings through application of more advanced technologies in a variety of residential and commercial end uses. The objectives of this report were to characterize the state and type of motor technologies used in residential and commercial appliances and equipment and to identify opportunities to reduce the energy consumption of electric motor-driven systems in the residential and commercial sectors through the use of advanced motor technologies. After analyzing the technical savings potential offered by motor upgrades and variable speed technologies, recommended actions are presented.

  6. Identification of salt-alloy combinations for thermal energy storage applications in advanced solar dynamic power systems

    NASA Technical Reports Server (NTRS)

    Whittenberger, J. D.; Misra, A. K.

    1987-01-01

    Thermodynamic calculations based on the available data for flouride salt systems reveal that a number of congruently melting compositions and eutectics exist which have the potential to meet the lightweight, high energy storage requirements imposed for advanced solar dynamic systems operating between about 1000 and 1400 K. Compatibility studies to determine suitable containment alloys to be used with NaF-22CaF2-13MgF2, NaF-32CaF2, and NaF-23MgF2 have been conducted at the eutectic temperature + 25 K for each system. For these three NaF-based eutectics, none of the common, commercially available high temperature alloys appear to offer adequate corrosion resistance for a long lifetime; however mild steel, pure nickel and Nb-1Zr could prove useful. These latter materials suggest the possibility that a strong, corrosion resistant, nonrefractory, elevated temperature alloy based on the Ni-Ni3Nb system could be developed.

  7. Energy and IAQ Implications of Residential Ventilation Cooling

    SciTech Connect

    Turner, William; Walker, Iain

    2014-08-01

    This study evaluates the energy, humidity and indoor air quality (IAQ) implications of residential ventilation cooling in all U.S. IECC climate zones. A computer modeling approach was adopted, using an advanced residential building simulation tool with airflow, energy and humidity models. An economizer (large supply fan) was simulated to provide ventilation cooling while outdoor air temperatures were lower than indoor air temperatures (typically at night). The simulations were performed for a full year using one-minute time steps to allow for scheduling of ventilation systems and to account for interactions between ventilation and heating/cooling systems.

  8. Solar Impulse's Solar-Powered Plane

    ScienceCinema

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2016-07-12

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  9. Solar Impulse's Solar-Powered Plane

    SciTech Connect

    Moniz, Ernest; Piccard, Bertrand; Reicher, Dan

    2013-07-08

    Solar Impulse lands in Washington, DC at Washington Dulles International Airport as part of its journey across the United States. Secretary Ernest Moniz speaks about how advancements like those at the Department of Energy are leading the way for innovations like the solar-powered plane. Footage of the solar-powered plane courtesy of Solar Impulse.

  10. College residential sleep environment.

    PubMed

    Sexton-Radek, Kathy; Hartley, Andrew

    2013-12-01

    College students regularly report increased sleep disturbances as well as concomitant reductions in performance (e.g., academic grades) upon entering college. Sleep hygiene refers to healthy sleep practices that are commonly used as first interventions in sleep disturbances. One widely used practice of this sort involves arranging the sleep environment to minimize disturbances from excessive noise and light at bedtime. Communal sleep situations such as those in college residence halls do not easily support this intervention. Following several focus groups, a questionnaire was designed to gather self-reported information on sleep disturbances in a college population. The present study used The Young Adult Sleep Environment Inventory (YASEI) and sleep logs to investigate the sleep environment of college students living in residential halls. A summary of responses indicated that noise and light are significant sleep disturbances in these environments. Recommendations are presented related to these findings.

  11. Development of Advanced CdTe Solar Cells Based on High Temperature Corning Glass Substrates: Cooperative Research and Development Final Report, CRADA Number CRD-10-373

    SciTech Connect

    Barnes, T.

    2013-08-01

    NREL has developed advanced processes for CdTe solar cells, but because of the temperature limitations of conventional soda lime glass, many of these processes have not been transferred to manufacturing. Corning is developing high temperature substrate glasses that are believed to be manufacturable and will lead to lower $/watt modules costs. The purpose of this CRADA is to evaluate these glasses in the advanced NREL processes. In addition, the CRADA seeks to develop manufacturable processes for transparent conductive oxide layers based on cadmium stannate.

  12. Analytical study of residential building with reflecting roofs

    SciTech Connect

    Zarr, R.R.

    1998-10-01

    This report presents an analysis of the effect of roof solar reflectance on the annual heating (cooling) loads, peak heating (cooling) loads, and roof temperatures of the residential buildings. The annual heating (cooling) loads, peak heating (cooling) loads, and exterior roof temperatures for a small compact ranch house are computed using the Thermal Analysis Research Program (TARP). The residential models, with minor modifications in the thermal envelope for different locations, are subjected to hourly weather data for one year compiled in the Weather Year for Energy Calculation (WYEC) for in the following locations: Birmingham, Alabama; Bismarck, North Dakota; Miami, Florida; Phoenix, Arizona; Portland, Maine; and, Washington, D.C. Building loads have been determined for a full factorial experimental design that varies the following parameters of the residential model: solar reflectance of the roof, ceiling thermal resistance, attic ventilation, and attic mass framing area. The computed results for annual heating (cooling) loads and peak heating (cooling) loads are illustrated graphically, both globally for all cities and locally for each geographic location. The effect of peak parameter is ranked (highest to lowest) for effect on annual heating and cooling loads, and peak heating and cooling loads. A parametric study plots the building loads as a function of roof solar reflectance for different levels of ceiling thermal resistances and for each geographic location.

  13. A test program for solar collectors

    NASA Technical Reports Server (NTRS)

    1980-01-01

    Rigorous environmental and performance tests qualify solar collector for use in residential solar-energy systems. Testing over 7 month period examined pressurized effects, wind and snow loading, hail damage, solar and thermal degradation, effects of pollutants, efficiency, and outgassing. Test procedures and results are summarized in tables, graphs, and text.

  14. Measured Performance of Residential Dehumidifiers Under Cyclic Operation

    SciTech Connect

    Winkler, J.; Christensen, D.; Tomerlin, J.

    2014-01-01

    Residential construction practices are progressing toward higher levels of energy efficiency. A proven strategy to save energy is to simultaneously increase building insulation levels and reduce outdoor air infiltration. Overall, this strategy results in a shift in the mix of latent and sensible space conditioning loads, requiring proportionally more moisture to be removed compared to standard homes. In this project, researchers at the National Renewable Energy Laboratory (NREL) developed steady state performance maps to predict dehumidifier performance at a variety of indoor conditions. However, installed heating, ventilating, and air-conditioning (HVAC) equipment rarely operates at steady state. Part load performance testing of residential dehumidifiers is not mandated by current test standards. Therefore, the team tested the part load performance of four residential dehumidifiers in NREL’s Advanced HVAC Systems Laboratory . The part load efficiency of each dehumidifier was measured under 13 cycling scenarios, and combined with NREL field data to develop part load fraction (PLF) performance curves under realistic cycling scenarios.

  15. Residential Demand Module - NEMS Documentation

    EIA Publications

    2014-01-01

    Model Documentation - Documents the objectives, analytical approach, and development of the National Energy Modeling System (NEMS) Residential Sector Demand Module. The report catalogues and describes the model assumptions, computational methodology, parameter estimation techniques, and FORTRAN source code.

  16. Performance verification of an air solar collector

    NASA Technical Reports Server (NTRS)

    Miller, D. C.; Romaker, R. F.

    1979-01-01

    Procedures and results of battery of qualification tests performed by independent certification agency on commercial solar collector are presented in report. Reported results were used as basis in judging collector suitable for field installation in residential and commerical buildings.

  17. Design data brochure: Solar hot air heater

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The design, installation, performance, and application of a solar hot air heater for residential, commercial and industrial use is reported. The system has been installed at the Concho Indian School in El Reno, Oklahoma.

  18. The NASA Solar System Exploration Virtual Institute: International Efforts in Advancing Lunar Science with Prospects for the Future

    NASA Astrophysics Data System (ADS)

    Schmidt, Gregory

    The NASA Solar System Exploration Research Virtual Institute (SSERVI), originally chartered in 2008 as the NASA Lunar Science Institute (NLSI), is chartered to advance both the scientific goals needed to enable human space exploration, as well as the science enabled by such exploration. NLSI and SSERVI have in succession been “institutes without walls,” fostering collaboration between domestic teams (7 teams for NLSI, 9 for SSERVI) as well as between these teams and the institutes’ international partners, resulting in a greater global endeavor. SSERVI teams and international partners participate in sharing ideas, information, and data arising from their respective research efforts, and contribute to the training of young scientists and bringing the scientific results and excitement of exploration to the public. The domestic teams also respond to NASA’s strategic needs, providing community-based responses to NASA needs in partnership with NASA’s Analysis Groups. Through the many partnerships enabled by NLSI and SSERVI, scientific results have well exceeded initial projections based on the original PI proposals, proving the validity of the virtual institute model. NLSI and SSERVI have endeavored to represent not just the selected and funded domestic teams, but rather the entire relevant scientific community; this has been done through many means such as the annual Lunar Science Forum (now re-named Exploration Science Forum), community-based grass roots Focus Groups on a wide range of topics, and groups chartered to further the careers of young scientists. Additionally, NLSI and SSERVI have co-founded international efforts such as the pan-European lunar science consortium, with an overall goal of raising the tide of lunar science (and now more broadly exploration science) across the world.

  19. The NASA Solar System Exploration Virtual Institute: International Efforts in Advancing Lunar Science with Prospects for the Future

    NASA Technical Reports Server (NTRS)

    Schmidt, Gregory K.

    2014-01-01

    The NASA Solar System Exploration Research Virtual Institute (SSERVI), originally chartered in 2008 as the NASA Lunar Science Institute (NLSI), is chartered to advance both the scientific goals needed to enable human space exploration, as well as the science enabled by such exploration. NLSI and SSERVI have in succession been "institutes without walls," fostering collaboration between domestic teams (7 teams for NLSI, 9 for SSERVI) as well as between these teams and the institutes' international partners, resulting in a greater global endeavor. SSERVI teams and international partners participate in sharing ideas, information, and data arising from their respective research efforts, and contribute to the training of young scientists and bringing the scientific results and excitement of exploration to the public. The domestic teams also respond to NASA's strategic needs, providing community-based responses to NASA needs in partnership with NASA's Analysis Groups. Through the many partnerships enabled by NLSI and SSERVI, scientific results have well exceeded initial projections based on the original PI proposals, proving the validity of the virtual institute model. NLSI and SSERVI have endeavored to represent not just the selected and funded domestic teams, but rather the entire relevant scientific community; this has been done through many means such as the annual Lunar Science Forum (now re-named Exploration Science Forum), community-based grass roots Focus Groups on a wide range of topics, and groups chartered to further the careers of young scientists. Additionally, NLSI and SSERVI have co-founded international efforts such as the pan-European lunar science consortium, with an overall goal of raising the tide of lunar science (and now more broadly exploration science) across the world.

  20. Data acquisition at a residential photovoltaic system

    NASA Astrophysics Data System (ADS)

    McIntyre, J. M.; Miller, G. N.

    A description is presented of the techniques employed for data collection and analysis in the study of a small residential photovoltaic (PV) system. A model home of approximately 139 sq m incorporated a PV array on the south-facing roof. The PV system was designed to interface directly to the local utility system through an inverter which converted the direct current output of the array to 60 Hz alternating current. Electric power could flow either from the utility lines into the house or vice versa. The solar panel consisted of 120 modules installed in a 5 x 24 array. Attention is given to initial problems, the conduction of a systems analysis, the data collection method, the equipment used in the data acquisition system, aspects of data collection, the encountered problems, and the results of the data acquisition project. It was found that the data acquisition system employed was effective for computer-compatible data collection.

  1. NASA advanced design program: Analysis, design, and construction of a solar powered aircraft. B.S. Thesis

    NASA Technical Reports Server (NTRS)

    Chan, Agnes; Conley, Kristin; Javorski, Christian T.; Cheung, Kwok-Hung; Crivelli, Paul M.; Torrey, Nancy P.; Traver, Michael L.

    1992-01-01

    Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as the most logical alternative source of power. The major objective of this project was to build a solar powered remotely controlled aircraft to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design was optimized for minimum weight and maximum strength of the structure. These design constraints necessitated a carbon fiber composite structure. Surya is a lightweight, durable aircraft capable of achieving level flight powered entirely by solar cells.

  2. Texas Solar Collaboration DOE Rooftop Solar Challenge City of Houston Project Summary

    SciTech Connect

    Ronk, Jennifer

    2013-02-14

    The City of Houston is committed to achieving a sustainable solar infrastructure. In 2008, Houston was named a United States Department of Energy (DOE) Solar America City. As a Solar America City, Houston teamed with the Houston Advanced Research Center (HARC), Sandia National Laboratory (Sandia), industry, and academia, to implement the Solar Houston Initiative and prepare the Solar Houston Plan. The Solar Houston initiative was focused on identifying and overcoming barriers associated with establishing a solar infrastructure that is incorporated into the City of Houston’s overall energy plan. A broad group of Houston area stakeholders, facilitated by HARC, came together to develop a comprehensive solar plan that went beyond technology to address barriers and establish demonstrations, public outreach, education programs and other activities. The plan included proposed scopes of work in four program areas: policies, solar integration, public outreach, and education. Through the support of the DOE SunShot Rooftop Solar Challenge (RSC) grant to the Texas Collaboration (San Antonio, Austin, and Hosuton), Houston has been able to implement several of the recommendations of the Solar Houston Plan. Specific recommendations that this project was able to support include; Working with the other Texas Solar America Cities (San Antonio and Austin), to harmonize permitting and inspection processes to simplify for installers and lower soft costs of installation; Participating in state level solar policy groups such as the Texas Renewable Energy Industries Association (TRIEA); Continued coordination with the local transmission and distribution utility (CenterPoint) and retail electric providers (REP); Identification of opportunities to improve permitting and interconnection; Providing training on PV systems to City inspectors; Educating the public by continuing outreach, training, and workshops, particularly using the the Green Building Resources Center; Evaluating methods of

  3. Global residential appliance standards

    SciTech Connect

    Turiel, I.; McMahon, J.E. ); Lebot, B. )

    1993-03-01

    In most countries, residential electricity consumption typically ranges from 20% to 40% of total electricity consumption. This energy is used for heating, cooling, refrigeration and other end-uses. Significant energy savings are possible if new appliance purchases are for models with higher efficiency than that of existing models. There are several ways to ensure or encourage such an outcome, for example, appliance rebates, innovative procurement, and minimum efficiency standards. This paper focuses on the latter approach. At the present time, the US is the only country with comprehensive appliance energy efficiency standards. However, many other countries, such as Australia, Canada, the European Community (EC), Japan and Korea, are considering enacting standards. The greatest potential impact of minimum efficiency standards for appliances is in the developing countries (e.g., China and India), where saturations of household appliances are relatively low but growing rapidly. This paper discusses the potential savings that could be achieved from global appliance efficiency standards for refrigerators and freezers. It also could be achieved from global appliance efficiency standards for refrigerators and freezers. It also discusses the impediments to establishing common standards for certain appliance types, such as differing test procedures, characteristics, and fuel prices. A methodology for establishing global efficiency standards for refrigerators and freezers is described.

  4. Residential Transactive Control Demonstration

    SciTech Connect

    Widergren, Steven E.; Fuller, Jason C.; Marinovici, Maria C.; Somani, Abhishek

    2014-02-19

    Arguably the most exciting aspect of the smart grid vision is the full participation of end-use resources with all forms of generation and energy storage in the reliable and efficient operation of an electric power system. Engaging all of these resources in a collaborative manner that respects the objectives of each resource, is sensitive to the system and local constraints of electricity flow, and scales to the large number of devices and systems participating is a grand challenge. Distributed decision-making system approaches have been presented and experimentation is underway. This paper reports on the preliminary findings of a residential demand response demonstration that uses the bidding transactions of supply and end-use air conditioning resources communicating with a real-time, 5 minute market to balance the various needs of the participants on a distribution feeder. The nature of the demonstration, the value streams being explored, and the operational scenarios implemented to characterize the system response are summarized along with preliminary findings.

  5. Preliminary design package for residential heating/cooling system: Rankine air conditioner redesign

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A summary of the preliminary redesign and development of a marketable single family heating and cooling system is presented. The interim design and schedule status of the residential (3-ton) redesign, problem areas and solutions, and the definition of plans for future design and development activities were discussed. The proposed system for a single-family residential heating and cooling system is a single-loop, solar-assisted, hydronic-to-warm-air heating subsystem with solar-assisted domestic water heating and a Rankine-driven expansion air-conditioning subsystem.

  6. Recent advances in water/alcohol-soluble π-conjugated materials: new materials and growing applications in solar cells.

    PubMed

    Duan, Chunhui; Zhang, Kai; Zhong, Chengmei; Huang, Fei; Cao, Yong

    2013-12-07

    Water/alcohol-soluble conjugated polymers (WSCPs) and small molecules (WSCSs) are materials that can be processed from water or other polar solvents. They provide good opportunities to fabricate multilayer organic optoelectronic devices without interface mixing by solution processing, and exhibit a promising interface modification ability for metal or metal oxide electrodes to greatly enhance the device performance of solar cells. Moreover, owing to their intriguing processability, WSCPs and WSCSs have great potential for applying environmentally friendly processing technologies to fabricate solar cells. In this review, the authors give an overview of recent developments in WSCPs and WSCSs, including their molecular design, material synthesis, functional principles and application as interface modification layers and photoactive components in emerging photovoltaic technologies such as organic/polymer solar cells, organic-inorganic hybrid solar cells and dye-sensitised solar cells.

  7. Space Station Freedom solar dynamic power generation

    NASA Technical Reports Server (NTRS)

    Springer, T.; Friefeld, Jerry M.

    1990-01-01

    Viewgraphs on Space Station Freedom solar dynamic power generation are presented. Topics covered include: prime contract activity; key solar dynamic power module requirements; solar dynamic heat receiver technology; and solar concentrator advanced development.

  8. Solar Sailing

    NASA Technical Reports Server (NTRS)

    Johnson, Les

    2009-01-01

    Solar sailing is a topic of growing technical and popular interest. Solar sail propulsion will make space exploration more affordable and offer access to destinations within (and beyond) the solar system that are currently beyond our technical reach. The lecture will describe solar sails, how they work, and what they will be used for in the exploration of space. It will include a discussion of current plans for solar sails and how advanced technology, such as nanotechnology, might enhance their performance. Much has been accomplished recently to make solar sail technology very close to becoming an engineering reality and it will soon be used by the world s space agencies in the exploration of the solar system and beyond. The first part of the lecture will summarize state-of-the-art space propulsion systems and technologies. Though these other technologies are the key to any deep space exploration by humans, robots, or both, solar-sail propulsion will make space exploration more affordable and offer access to distant and difficult destinations. The second part of the lecture will describe the fundamentals of space solar sail propulsion and will describe the near-, mid- and far-term missions that might use solar sails as a propulsion system. The third part of the lecture will describe solar sail technology and the construction of current and future sailcraft, including the work of both government and private space organizations.

  9. Recent advances in polymer solar cells: realization of high device performance by incorporating water/alcohol-soluble conjugated polymers as electrode buffer layer.

    PubMed

    He, Zhicai; Wu, Hongbin; Cao, Yong

    2014-02-01

    This Progress Report highlights recent advances in polymer solar cells with special attention focused on the recent rapid-growing progress in methods that use a thin layer of alcohol/water-soluble conjugated polymers as key component to obtain optimized device performance, but also discusses novel materials and device architectures made by major prestigious institutions in this field. We anticipate that due to drastic improvements in efficiency and easy utilization, this method opens up new opportunities for PSCs from various material systems to improve towards 10% efficiency, and many novel device structures will emerge as suitable architectures for developing the ideal roll-to-roll type processing of polymer-based solar cells.

  10. Expert Meeting Report: Achieving the Best Installed Performance from High-Efficiency Residential Gas Furnaces

    SciTech Connect

    Brand, Larry

    2012-03-01

    This report describes a Building America expert meeting hosted on July 28, 2011, by the Partnership for Advanced Residential Retrofit (PARR) team. The purpose of this meeting was to identify installation practices that provide the best installed efficiency for residential gas furnaces, explain how AFUE and field efficiency can differ, and investigate the impact of installation practices on the efficiency and long-term durability of the furnace.

  11. Expert Meeting Report: Achieving the Best Installed Performance from High-Efficiency Residential Gas Furnaces

    SciTech Connect

    Brand, L.

    2012-03-01

    This report describes a Building America expert meeting hosted on July 28, 2011, by the Partnership for Advanced Residential Retrofit team. The purpose of this meeting was to identify installation practices that provide the best installed efficiency for residential gas furnaces, explain how AFUE and field efficiency can differ, and investigate the impact of installation practices on the efficiency and long-term durability of the furnace.

  12. Advanced planetary studies

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Results of planetary advanced studies and planning support are summarized. The scope of analyses includes cost estimation research, planetary mission performance, penetrator advanced studies, Mercury mission transport requirements, definition of super solar electric propulsion/solar sail mission discriminators, and advanced planning activities.

  13. Structural Code Considerations for Solar Rooftop Installations.

    SciTech Connect

    Dwyer, Stephen F.; Dwyer, Brian P.; Sanchez, Alfred

    2014-12-01

    Residential rooftop solar panel installations are limited in part by the high cost of structural related code requirements for field installation. Permitting solar installations is difficult because there is a belief among residential permitting authorities that typical residential rooftops may be structurally inadequate to support the additional load associated with a photovoltaic (PV) solar installation. Typical engineering methods utilized to calculate stresses on a roof structure involve simplifying assumptions that render a complex non-linear structure to a basic determinate beam. This method of analysis neglects the composite action of the entire roof structure, yielding a conservative analysis based on a rafter or top chord of a truss. Consequently, the analysis can result in an overly conservative structural analysis. A literature review was conducted to gain a better understanding of the conservative nature of the regulations and codes governing residential construction and the associated structural system calculations.

  14. Analysis of field test data on residential heating and cooling

    NASA Astrophysics Data System (ADS)

    Talbert, S. G.

    1980-12-01

    The computer program using field site data collected on 48 homes located in six cities in different climatic regions of the United States is discussed. In addition, a User's Guide was prepared for the computer program which is contained in a separate two-volume document entitled User's Guide for REAP: Residential Energy Analysis Program. Feasibility studies were conducted pertaining to potential improvements for REAP, including: the addition of an oil-furnace model; improving the infiltration subroutine; adding active and/or passive solar subroutines; incorporating a thermal energy storage model; and providing dual HVAC systems (e.g., heat pump-gas furnace). The purpose of REAP is to enable building designers and energy analysts to evaluate how such factors as building design, weather conditions, internal heat loads, and HVAC equipment performance, influence the energy requirements of residential buildings.

  15. Making Cents Out of Solar: Put More Power Into Your Building Plans

    SciTech Connect

    2008-01-01

    This is a brochure developed specifically for residential home builders. It provides information on basic solar facts, selling tips, and important resources when incorporating solar technologies into building plans.

  16. Making Cents Out of Solar: Put More Power Into Your Building Plans (Brochure)

    SciTech Connect

    Not Available

    2008-01-01

    This is a brochure developed specifically for residential home builders. It provides information on basic solar facts, selling tips, and important resources when incorporating solar technologies into building plans.

  17. The adoption of residential solar photovoltaic systems in the presence of a financial incentive: A case study of consumer experiences with the Renewable Energy Standard Offer Program in Ontario (Canada)

    NASA Astrophysics Data System (ADS)

    Adachi, Christopher William Junji

    2009-12-01

    Traditionally, high initial capital costs and lengthy payback periods have been identified as the most significant barriers that limit the diffusion of solar photovoltaic (PV) systems. In response, the Ontario Government, through the Ontario Power Authority (OPA), introduced the Renewable Energy Standard Offer Program (RESOP) in November, 2006. The RESOP offers owners of solar PV systems with a generation capacity under 10MW a 20 year contract to sell electricity back to the grid at a guaranteed rate of $0.42/kWh. While it is the intent of incentive programs such as the RESOP to begin to lower financial barriers in order to increase the uptake of solar PV systems, there is no guarantee that the level of participation will in fact rise. The "on-the-ground" manner in which consumers interact with such an incentive program ultimately determines its effectiveness. The purpose of this thesis is to analyze the relationship between the RESOP and solar PV system consumers. To act on this purpose, the experiences of current RESOP participants are presented, wherein the factors that are either hindering or promoting utilization of the RESOP and the adoption of solar PV systems are identified. This thesis was conducted in three phases--a literature review, preliminary key informant interviews, and primary RESOP participant interviews--with each phase informing the scope and design of the subsequent stage. First, a literature survey was completed to identify and to understand the potential drivers and barriers to the adoption of a solar PV system from the perspective of a consumer. Second, nine key informant interviews were completed to gain further understanding regarding the specific intricacies of the drivers and barriers in the case of Ontario, as well as the overall adoption system in the province. These interviews were conducted between July and September, 2008. Third, interviews with 24 RESOP participants were conducted; they constitute the primary data set. These

  18. Redefining Residential: Integrating Evidence-Based Practices

    ERIC Educational Resources Information Center

    Residential Treatment for Children & Youth, 2009

    2009-01-01

    This is the fifth in a series of papers being issued by the American Association of Children's Residential Centers (AACRC) regarding key program and policy issues facing the field of residential treatment. AACRC is the longest standing national association focused exclusively on the needs of children who require residential treatment and their…

  19. 10 CFR 429.18 - Residential furnaces.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Residential furnaces. 429.18 Section 429.18 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.18 Residential furnaces. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to residential furnaces;...

  20. 10 CFR 429.18 - Residential furnaces.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Residential furnaces. 429.18 Section 429.18 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.18 Residential furnaces. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to residential furnaces;...

  1. 10 CFR 429.18 - Residential furnaces.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Residential furnaces. 429.18 Section 429.18 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.18 Residential furnaces. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to residential furnaces;...

  2. 5 CFR 1655.20 - Residential loans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 3 2012-01-01 2012-01-01 false Residential loans. 1655.20 Section 1655.20 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD LOAN PROGRAM § 1655.20 Residential loans. (a) A residential loan will be made only for the purchase or construction of the...

  3. 5 CFR 1655.20 - Residential loans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 3 2013-01-01 2013-01-01 false Residential loans. 1655.20 Section 1655.20 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD LOAN PROGRAM § 1655.20 Residential loans. (a) A residential loan will be made only for the purchase or construction of the...

  4. Storage, transportation, and atomization of CWF for residential applications

    SciTech Connect

    Breault, R.; Sayre, A.

    1990-07-01

    The proposed test program will examine the stability and rheology of the coal water fuels (CWFs) prepared from various beneficiated coal products made from the following coals: Illinois No. 6, Wyodak, and Upper Elkhorn No. 3. Fuel characterization will include: particle size distribution, ultimate and proximate analyses of coal, ash composition, ash fusion temperature, and solids concentration. For rheological characteristics, data will be obtained at varying shear rates, temperature, and agitation or recirculation in the bulk storage tanks. The effect of freeze-thaw on the stability and rheology of the CWF will be evaluated. Control of the environmental conditions will be examined by means of formulation additives, including the addition of freezing point depressants and biocides. Bulk storage studies will involve testing CWF stability characteristics with and without agitation and recirculation. The design of the storage tank will be reviewed, and the effectiveness of cone bottom and dish bottom tanks will be tested. The CWF storage and handling tests will be carried out at Tecogen's CWF-fired advanced combustor facility. This quarter, under Task 2, two coal water slurry fuels were produced from the baseline coal. Chemical stability tests and mechanical resuspension tests were begun under the Task 3 effort. Residential storage work was also initiated and a bladder tank developed. Residential handling tests were initiated under the Task 5 effort to develop pressure drop characteristics for the slurries at residential flows in residential type components. 5 refs., 9 figs., 8 tabs.

  5. Application of advanced computational procedures for modeling solar-wind interactions with Venus: Theory and computer code

    NASA Technical Reports Server (NTRS)

    Stahara, S. S.; Klenke, D.; Trudinger, B. C.; Spreiter, J. R.

    1980-01-01

    Computational procedures are developed and applied to the prediction of solar wind interaction with nonmagnetic terrestrial planet atmospheres, with particular emphasis to Venus. The theoretical method is based on a single fluid, steady, dissipationless, magnetohydrodynamic continuum model, and is appropriate for the calculation of axisymmetric, supersonic, super-Alfvenic solar wind flow past terrestrial planets. The procedures, which consist of finite difference codes to determine the gasdynamic properties and a variety of special purpose codes to determine the frozen magnetic field, streamlines, contours, plots, etc. of the flow, are organized into one computational program. Theoretical results based upon these procedures are reported for a wide variety of solar wind conditions and ionopause obstacle shapes. Plasma and magnetic field comparisons in the ionosheath are also provided with actual spacecraft data obtained by the Pioneer Venus Orbiter.

  6. Building-Integrated Photovoltaics (BIPV) in the Residential Sector: An Analysis of Installed Rooftop System Prices

    SciTech Connect

    James, T.; Goodrich, A.; Woodhouse, M.; Margolis, R.; Ong, S.

    2011-11-01

    For more than 30 years, there have been strong efforts to accelerate the deployment of solar-electric systems by developing photovoltaic (PV) products that are fully integrated with building materials. This report examines the status of building-integrated PV (BIPV), with a focus on the cost drivers of residential rooftop systems, and explores key opportunities and challenges in the marketplace.

  7. Advancing Solar Irradiance Measurement for Climate-Related Studies: Accurate Constraint on Direct Aerosol Radiative Effect (DARE)

    NASA Technical Reports Server (NTRS)

    Tsay, Si-Chee; Ji, Q. Jack

    2011-01-01

    Earth's climate is driven primarily by solar radiation. As summarized in various IPCC reports, the global average of radiative forcing for different agents and mechanisms, such as aerosols or CO2 doubling, is in the range of a few W/sq m. However, when solar irradiance is measured by broadband radiometers, such as the fleet of Eppley Precision Solar Pyranometers (PSP) and equivalent instrumentation employed worldwide, the measurement uncertainty is larger than 2% (e.g., WMO specification of pyranometer, 2008). Thus, out of the approx. 184 W/sq m (approx.263 W/sq m if cloud-free) surface solar insolation (Trenberth et al. 2009), the measurement uncertainty is greater than +/-3.6 W/sq m, overwhelming the climate change signals. To discern these signals, less than a 1 % measurement uncertainty is required and is currently achievable only by means of a newly developed methodology employing a modified PSP-like pyranometer and an updated calibration equation to account for its thermal effects (li and Tsay, 2010). In this talk, we will show that some auxiliary measurements, such as those from a collocated pyrgeometer or air temperature sensors, can help correct historical datasets. Additionally, we will also demonstrate that a pyrheliometer is not free of the thermal effect; therefore, comparing to a high cost yet still not thermal-effect-free "direct + diffuse" approach in measuring surface solar irradiance, our new method is more economical, and more likely to be suitable for correcting a wide variety of historical datasets. Modeling simulations will be presented that a corrected solar irradiance measurement has a significant impact on aerosol forcing, and thus plays an important role in climate studies.

  8. Conceptual design of a self-deployable, high performance parabolic concentrator for advanced solar-dynamic power systems

    NASA Technical Reports Server (NTRS)

    Dehne, Hans Joachim; Duffy, Donald R.

    1989-01-01

    A summary is presented of the concentrator conceptual design work performed under a NASA-funded project. The design study centers around two basic efforts: conceptual design of a self-deploying, high-performance parabolic concentrator; and materials selection for a lightweight, shape-stable concentrator. The primary structural material selected for the concentrator is PEEK/carbon fiber composite. The deployment concept utilizes rigid gore-shaped reflective panels. The assembled concentrator takes a circular shape with a void in the center. The deployable solar concentrator concept is applicable to a range of solar dynamic power systems of 25 kWe to more than 75 kWe.

  9. Development of Residential Prototype Building Models and Analysis System for Large-Scale Energy Efficiency Studies Using EnergyPlus

    SciTech Connect

    Mendon, Vrushali V.; Taylor, Zachary T.

    2014-09-10

    ABSTRACT: Recent advances in residential building energy efficiency and codes have resulted in increased interest in detailed residential building energy models using the latest energy simulation software. One of the challenges of developing residential building models to characterize new residential building stock is to allow for flexibility to address variability in house features like geometry, configuration, HVAC systems etc. Researchers solved this problem in a novel way by creating a simulation structure capable of creating fully-functional EnergyPlus batch runs using a completely scalable residential EnergyPlus template system. This system was used to create a set of thirty-two residential prototype building models covering single- and multifamily buildings, four common foundation types and four common heating system types found in the United States (US). A weighting scheme with detailed state-wise and national weighting factors was designed to supplement the residential prototype models. The complete set is designed to represent a majority of new residential construction stock. The entire structure consists of a system of utility programs developed around the core EnergyPlus simulation engine to automate the creation and management of large-scale simulation studies with minimal human effort. The simulation structure and the residential prototype building models have been used for numerous large-scale studies, one of which is briefly discussed in this paper.

  10. Advancements in n-type base crystalline silicon solar cells and their emergence in the photovoltaic industry.

    PubMed

    ur Rehman, Atteq; Lee, Soo Hong

    2013-01-01

    The p-type crystalline silicon wafers have occupied most of the solar cell market today. However, modules made with n-type crystalline silicon wafers are actually the most efficient modules up to date. This is because the material properties offered by n-type crystalline silicon substrates are suitable for higher efficiencies. Properties such as the absence of boron-oxygen related defects and a greater tolerance to key metal impurities by n-type crystalline silicon substrates are major factors that underline the efficiency of n-type crystalline silicon wafer modules. The bi-facial design of n-type cells with good rear-side electronic and optical properties on an industrial scale can be shaped as well. Furthermore, the development in the industrialization of solar cell designs based on n-type crystalline silicon substrates also highlights its boost in the contributions to the photovoltaic industry. In this paper, a review of various solar cell structures that can be realized on n-type crystalline silicon substrates will be given. Moreover, the current standing of solar cell technology based on n-type substrates and its contribution in photovoltaic industry will also be discussed.

  11. Advancements in n-Type Base Crystalline Silicon Solar Cells and Their Emergence in the Photovoltaic Industry

    PubMed Central

    ur Rehman, Atteq; Lee, Soo Hong

    2013-01-01

    The p-type crystalline silicon wafers have occupied most of the solar cell market today. However, modules made with n-type crystalline silicon wafers are actually the most efficient modules up to date. This is because the material properties offered by n-type crystalline silicon substrates are suitable for higher efficiencies. Properties such as the absence of boron-oxygen related defects and a greater tolerance to key metal impurities by n-type crystalline silicon substrates are major factors that underline the efficiency of n-type crystalline silicon wafer modules. The bi-facial design of n-type cells with good rear-side electronic and optical properties on an industrial scale can be shaped as well. Furthermore, the development in the industrialization of solar cell designs based on n-type crystalline silicon substrates also highlights its boost in the contributions to the photovoltaic industry. In this paper, a review of various solar cell structures that can be realized on n-type crystalline silicon substrates will be given. Moreover, the current standing of solar cell technology based on n-type substrates and its contribution in photovoltaic industry will also be discussed. PMID:24459433

  12. Solar-powered air-conditioning

    NASA Technical Reports Server (NTRS)

    Clark, D. C.; Rousseau, J.

    1977-01-01

    Report focuses on recent study on development of solar-powered residential air conditioners and is based on selected literature through 1975. Its purposes are to characterize thermal and mechanical systems that might be useful in development of Rankine-cycle approach to solar cooling and assessment of a Lithium Bromide/Water absorption cycle system.

  13. User evaluation study of passive solar residences

    SciTech Connect

    Towle, S.

    1980-03-01

    Speculation exists regarding the readiness of various passive techniques for commercialization and the market potential for residential applications. This paper discusses the preliminary findings of a market assessment study designed to document user experiences with passive solar energy. Owners and builders of passive solar homes were interviewed and asked to comment on personal experiences with their homes.

  14. Solar Heating and Cooling: An Economic Assessment.

    ERIC Educational Resources Information Center

    McGarity, Arthur E.

    This study serves as an introduction to the important economic considerations that are necessary for an assessment of the potential for solar heating and cooling in the United States. The first chapter introduces the technology that is used to tap solar energy for residential and commercial applications and illustrates the potential significance…

  15. An energy used model of the residential sector

    NASA Astrophysics Data System (ADS)

    Oneal, D. L.; Hirst, E.

    1980-11-01

    An energy simulation model for residential energy uses and costs from 1970 through 2000 estimates annual consumption of four fuels, eight end uses, and three housing types. The model also evaluates annual equipment installation, ownership, and equipment costs including charges for improving thermal performance of new and existing housing. An example of the model application is given by estimating the energy and economic factors of alternate water heating conservation options; they show the advantages of heat pump water heaters over conventional and solar units.

  16. Solar, Install, Mount, Production, Labor, Equipment Balance of Systems

    SciTech Connect

    Gentry, Russell; Al-Haddad, Tristan; Valdes, Francisco; Caravati, Kevin; Goodman, Joseph

    2015-08-27

    The GTRI led project team in partnership with the DOE, universities, and numerous industry leaders, have advanced the mission of the DOE EERE, the Solar Energy Technologies Program, and the SunShot Initiative by accelerating the research, development, and demonstration of solar PV technologies that provide Extreme Balance of Systems Cost Reductions (BOS-X). The research produced 132 design concepts, resulting in 19 invention disclosures, five patent applications, four 90% pre-commercial designs, and three licensed technologies. Technology practice rights were obtained by an industry partner, and a new solar commercial start-up company was launched in Atlanta as a result of this project. Innovations in residential, commercial, and utility scale balance of systems technologies were realized through an unprecedented multi-disciplinary university/industry partnership with over 50 students and 24 faculty members that produced 18 technical publications, a PhD thesis, and two commercially deployed operating prototypes. The technical effectiveness and economic feasibility of the multidisciplinary systems based approach executed by the project team was realized through 1) a comprehensive evaluation of industry, regulatory, and public stakeholder requirements; 2) numerous industry/student/faculty engagements in design studios, technical conferences, and at solar PV installation sites; 3) time and motion studies with domain experts that provided technical data and costs for each phase and component of the solar PV installation processes; 4) extensive wind tunnel and systems engineering modeling; and 5) design, construction, and demonstration of the selected technologies in the field at high profile sites in Atlanta. The SIMPLE BOS project has benefitted the public in the following ways: • Workforce development: The launch of a start-up company to commercialize the DOE funded SIMPLE BoS designs has directly created 9 new jobs in the State of Georgia. As of November 2014, the

  17. On the Path to SunShot - The Role of Advancements in Solar Photovoltaic Efficiency, Reliability, and Costs

    SciTech Connect

    Woodhouse, Michael; Jones-Albertus, Rebecca; Feldman, David; Fu, Ran; Horowitz, Kelsey; Chung, Donald; Jordan, Dirk; Kurtz, Sarah

    2016-05-01

    Although tremendous progress has been made in reducing the cost of PV systems, additional LCOE reductions of 40%–50% between 2015 and 2020 will be required to reach the SunShot Initiative’s targets (see Woodhouse et al. 2016). Understanding the tradeoffs between installed prices and other PV system characteristics—such as module efficiency, module degradation rate, and system lifetime—are vital. For example, with 29%-efficient modules and high reliability (a 50-year lifetime and a 0.2%/year module degradation rate), a residential PV system could achieve the SunShot LCOE goal with modules priced at almost $1.20/W. But change the lifetime to 10 years and the degradation rate to 2%/year, and the system would need those very high-efficiency modules at zero cost to achieve the same LCOE. Although these examples are extreme, they serve to illustrate the wide range of technological combinations that could help drive PV toward the LCOE goals. SunShot’s PV roadmaps illustrate specific potential pathways to the target cost reductions.

  18. SolarTile: A rooftop integrated photovoltaic system. Phase 1, final report

    SciTech Connect

    1998-03-26

    AstroPower, Royal Group Technologies, and Solar Design Associates are jointly developing an integrated photovoltaic roofing system for residential and light commercial building applications. This family of products will rely heavily on the technological development of a roofing tile made from recycled plastic and innovative module fabrication and encapsulation processes in conjunction with an advanced Silicon-Film{trademark} solar cell product. This solar power generating roofing product is presently being referred to as the SolarTile. A conceptual drawing of the solar roofing tile is shown. The SolarTile will be integrated with non-solar tiles in a single roof installation permitting ease of assembly and the ability to use conventional roofing techniques at ridges, valleys, and eaves. The Phase 1 effort included tasks aimed at the development of the proposed product concept; product manufacturing or fabrication, and installation cost estimates; business planning; and a market assessment of the proposed product, including target selling prices, target market sectors, size estimates for each market sector, and planned distribution mechanisms for market penetration. Technical goals as stated in the Phase 1 proposal and relevant progress are reported.

  19. Evaluation of High-Power Solar Electric Propulsion using Advanced Ion, Hall, MPD, and PIT Thrusters for Lunar and Mars Cargo Missions

    NASA Technical Reports Server (NTRS)

    Frisbee, Robert H.

    2006-01-01

    This paper presents the results of mission analyses that expose the advantages and disadvantages of high-power (MWe-class) Solar Electric Propulsion (SEP) for Lunar and Mars Cargo missions that would support human exploration of the Moon and Mars. In these analyses, we consider SEP systems using advanced Ion thrusters (the Xenon [Xe] propellant Herakles), Hall thrusters (the Bismuth [Bi] propellant Very High Isp Thruster with Anode Layer [VHITAL], magnetoplasmadynamic (MPD) thrusters (the Lithium [Li] propellant Advanced Lithium-Fed, Applied-field Lorentz Force Accelerator (ALFA2), and pulsed inductive thruster (PIT) (the Ammonia [NH3] propellant Nuclear-PIT [NuPIT]). The analyses include comparison of the advanced-technology propulsion systems (VHITAL, ALFA2, and NuPIT) relative to state-of-theart Ion (Herakles) propulsion systems and quantify the unique benefits of the various technology options such as high power-per-thruster (and/or high power-per-thruster packaging volume), high specific impulse (Isp), high-efficiency, and tankage mass (e.g., low tankage mass due to the high density of bismuth propellant). This work is based on similar analyses for Nuclear Electric Propulsion (NEP) systems.

  20. Framework for the mapping of the monthly average daily solar radiation using an advanced case-based reasoning and a geostatistical technique.

    PubMed

    Lee, Minhyun; Koo, Choongwan; Hong, Taehoon; Park, Hyo Seon

    2014-04-15

    For the effective photovoltaic (PV) system, it is necessary to accurately determine the monthly average daily solar radiation (MADSR) and to develop an accurate MADSR map, which can simplify the decision-making process for selecting the suitable location of the PV system installation. Therefore, this study aimed to develop a framework for the mapping of the MADSR using an advanced case-based reasoning (CBR) and a geostatistical technique. The proposed framework consists of the following procedures: (i) the geographic scope for the mapping of the MADSR is set, and the measured MADSR and meteorological data in the geographic scope are collected; (ii) using the collected data, the advanced CBR model is developed; (iii) using the advanced CBR model, the MADSR at unmeasured locations is estimated; and (iv) by applying the measured and estimated MADSR data to the geographic information system, the MADSR map is developed. A practical validation was conducted by applying the proposed framework to South Korea. It was determined that the MADSR map developed through the proposed framework has been improved in terms of accuracy. The developed MADSR map can be used for estimating the MADSR at unmeasured locations and for determining the optimal location for the PV system installation.

  1. Photovoltaics, the solar electric solution

    NASA Astrophysics Data System (ADS)

    Beach, C. D.; Litka, A. H.

    Direct conversion of solar energy to electricity by photovoltaic devices (solar cells) may be the most promising solution to the current energy problem. Photovoltaic energy systems provide a clean, simple method of energy conversion, and are reliable, safe, and flexible with respect to size (modular). The federal government is trying to commercialize photovoltaics by funding research on new materials and manufacturing processes. Earliest commercialization will be in residential systems, where the power grid back-up provides for a reliable electrical system without storage costs. The Florida Solar Energy Center has been operating a 5 kW experimental residential facility since 1980. The facility showed an average solar irradiance in the 62.5 sq m panels of 264 kw-hours/day from December 1980 through February 1981. The overall system efficiency was 7%, and the inverter operated with an ac output/dc input efficiency of 85-90%, depending on input levels.

  2. Analysis of code related responses from the solar demonstration program

    NASA Astrophysics Data System (ADS)

    1980-01-01

    The building regulatory information gathered during the course of the Residential Solar Demonstration Program from inception of the program through September 30, 1978 is documented. It is concluded that existing codes do not present a barrier to the installation and acceptance of solar systems; however, code officials need additional training and better back-up material to properly evaluate solar systems.

  3. Interior design for passive solar homes

    SciTech Connect

    Breen, J. C.

    1981-07-01

    The increasing emphasis on refinement of passive solar systems has brought recognition to interior design as an integral part of passive solar architecture. Interior design can be used as a finetuning tool minimizing many of the problems associated with passive solar energy use in residential buildings. In addition, treatment of interior space in solar model homes may be a prime factor in determining sales success. A new style of interior design is evolving in response to changes in building form incorporating passive solar design features. The psychology behind passive solar architecture is reflected in interiors, and selection of interior components increasingly depends on the functional suitability of various interior elements.

  4. Advanced Stirling conversion systems for terrestrial applications

    NASA Technical Reports Server (NTRS)

    Shaltens, R. K.

    1987-01-01

    Under the Department of Energy's (DOE) Solar Thermal Technology Program, Sandia National Laboratories (SNLA) is developing heat engines for terrestrial Solar Distributed Heat Receivers. SNLA has identified the Stirling to be one of the most promising candidates for the terrestrial applications. The free-piston Stirling engine (FPSE) has the potential to meet the DOE goals for both performance and cost. The National Aeronautics and Space Administration (NASA) Lewis Research Center (LeRC) is conducting free-piston Stirling activities which are directed toward a dynamic power source for space applications. Space power system requirements include high efficiency, very long life, high reliability and low vibration. The FPSE has the potential for future high power space conversion systems, either solar or nuclear. Generic free-piston technology is currently being developed by LeRC for DOE/ORNL for use with a residential heat pump under an Interagency Agreement. Since 1983, the SP-100 Program (DOD/NASA/DOE) is developing dynamic power sources for space. Although both applications (heat pump and space power) appear to be quite different, their requirements complement each other. A cooperative Interagency Agreement (IAA) was signed in 1985 with NASA Lewis to provide technical management for an Advanced Stirling Conversion System (ASCS) for SNLA. Conceptual design(s) using a free-piston Stirling (FPSE), and a heat pipe will be discussed. The ASCS will be designed using technology which can reasonably be expected to be available in the 1980's.

  5. Integrated residential photovoltaic array development

    NASA Technical Reports Server (NTRS)

    Shepard, N. F., Jr.

    1981-01-01

    An optimum integrated residential photovoltaic array/module is addressed. Nineteen existing or proposed systems intended for residential applications are described. Each of these systems is rated against a comprehensive set of evaluation criteria in an effort to formulate three module design concepts for further study and analysis. This evaluation led to a number of observations which are enumerated and should be considered in future module and array designs. Three module concepts are presented as baseline design approaches to be further analyzed and optimized. These options include: (1) a rectangular, direct mounted, shingle type module; (2) an integrally mounted module with nonconductive exposed elements; and (3) an aluminum framed, stand off module. Preliminary design drawings are presented for each of these module configurations.

  6. Evaluation of two fiber optic-based solar collection and distribution systems for advanced space life support

    NASA Technical Reports Server (NTRS)

    Jack, D. A.; Nakamura, T.; Sadler, P.; Cuello, J. L.

    2002-01-01

    Growing plants in an enclosed controlled environment is crucial in developing bioregenerative life-support systems (BLSS) for space applications. The major challenge currently facing a BLSS is the extensive use of highly energy-intensive electric light sources, which leads to substantial energy wastes through heat dissipations by these lamps. An alternative lighting strategy is the use of a solar irradiance collection, transmission, and distribution system (SICTDS). Two types of fiber optic-based SICTDS, a Fresnel-lens Himawari and a parabolic-mirror optical waveguide (OW) lighting system, were evaluated. The overall efficiency for the OW SICTDS of 40.5% exceeded by 75% that for the Himawari of 23.2%. The spectral distributions of the light delivered by the Himawari and the OW SICTDS were almost identical and had practically no difference from that of terrestrial solar radiation. The ratios of photosynthetically active radiation (PAR) to total emitted radiation (k) of 0.39 +/- 0.02 for the Himawari and 0.41 +/- 0.04 for the OW SICTDS were statistically indistinguishable, were not significantly different from that of 0.042 +/- 0.01 for terrestrial solar radiation, and were comparable to that of 0.35 for a high-pressure sodium (HPS) lamp. The coefficients of variation (CV) of 0.34 and 0.39 for PPF distributions, both at 50 mm X 50 mm square grid arrays, corresponding to the Himawari and the OW SICTDS, respectively, were comparable with each other but were both significantly greater than the CV of 0.08 corresponding to the HPS lamp. The average fresh weight or dry weight of lettuce grown in the solar chamber with either the Himawari or the OW SICTDS showed no statistical difference from the average fresh weight or dry weight of lettuce grown in the reference chamber with the HPS lamp. The results of this study suggest that an SICTDS could help reduce the electric power demand in a BLSS.

  7. Evaluation of two fiber optic-based solar collection and distribution systems for advanced space life support.

    PubMed

    Jack, D A; Nakamura, T; Sadler, P; Cuello, J L

    2002-01-01

    Growing plants in an enclosed controlled environment is crucial in developing bioregenerative life-support systems (BLSS) for space applications. The major challenge currently facing a BLSS is the extensive use of highly energy-intensive electric light sources, which leads to substantial energy wastes through heat dissipations by these lamps. An alternative lighting strategy is the use of a solar irradiance collection, transmission, and distribution system (SICTDS). Two types of fiber optic-based SICTDS, a Fresnel-lens Himawari and a parabolic-mirror optical waveguide (OW) lighting system, were evaluated. The overall efficiency for the OW SICTDS of 40.5% exceeded by 75% that for the Himawari of 23.2%. The spectral distributions of the light delivered by the Himawari and the OW SICTDS were almost identical and had practically no difference from that of terrestrial solar radiation. The ratios of photosynthetically active radiation (PAR) to total emitted radiation (k) of 0.39 +/- 0.02 for the Himawari and 0.41 +/- 0.04 for the OW SICTDS were statistically indistinguishable, were not significantly different from that of 0.042 +/- 0.01 for terrestrial solar radiation, and were comparable to that of 0.35 for a high-pressure sodium (HPS) lamp. The coefficients of variation (CV) of 0.34 and 0.39 for PPF distributions, both at 50 mm X 50 mm square grid arrays, corresponding to the Himawari and the OW SICTDS, respectively, were comparable with each other but were both significantly greater than the CV of 0.08 corresponding to the HPS lamp. The average fresh weight or dry weight of lettuce grown in the solar chamber with either the Himawari or the OW SICTDS showed no statistical difference from the average fresh weight or dry weight of lettuce grown in the reference chamber with the HPS lamp. The results of this study suggest that an SICTDS could help reduce the electric power demand in a BLSS.

  8. Fluidized-bed technology enabling the integration of high temperature solar receiver CSP systems with steam and advanced power cycles

    SciTech Connect

    Sakadjian, B.; Hu, S.; Maryamchik, M.; Flynn, T.; Santelmann, K.; Ma, Z.

    2015-06-05

    Solar Particle Receivers (SPR) are under development to drive concentrating solar plants (CSP) towards higher operating temperatures to support higher efficiency power conversion cycles. The novel high temperature SPR-based CSP system uses solid particles as the heat transfer medium (HTM) in place of the more conventional fluids such as molten salt or steam used in current state-of-the-art CSP plants. The solar particle receiver (SPR) is designed to heat the HTM to temperatures of 800 °C or higher which is well above the operating temperatures of nitrate-based molten salt thermal energy storage (TES) systems. The solid particles also help overcome some of the other challenges associated with molten salt-based systems such as freezing, instability and degradation. The higher operating temperatures and use of low cost HTM and higher efficiency power cycles are geared towards reducing costs associated with CSP systems. This paper describes the SPR-based CSP system with a focus on the fluidized-bed (FB) heat exchanger and its integration with various power cycles. Furthermore, the SPR technology provides a potential pathway to achieving the levelized cost of electricity (LCOE) target of $0.06/kWh that has been set by the U.S. Department of Energy's SunShot initiative.

  9. Demonstration of an advanced solar garden with a water ceiling. Final technical report, July 1, 1979-June 30, 1980

    SciTech Connect

    Maes, R.; Riseng, C.; Thomas, G.; Mandeville, M.

    1980-09-01

    A history of the solar garden with the addition of the transparent water ceiling is presented, and a statement of the overall goals of the program is given. The objectives of the water ceiling grant are detailed. The rationale of the transparent water ceiling is developed and its implementation in the solar garden is described. The experimental procedures for evaluating the water ceiling as an integral part of an ongoing garden agricultural experiment are discussed and the results presented. The water ceiling has proven useful in providing extra thermal capacity to the solar garden. It provides heat at night after the water has been warmed during the day and retards overheating in the daytime by absorbing infrared energy into the water. In growing non-flowering plants, such as lettuce and Chinese cabbage, the water ceiling showed no noticeable degradation in yield or maturation rate. In flowering plants, such as tomatoes, the reduced light levels delayed yields by a couple of weeks but the total yield was only slightly diminished. In geographic areas where there is less cloud cover than in Michigan the water ceiling could be much more effective.

  10. Fluidized-bed technology enabling the integration of high temperature solar receiver CSP systems with steam and advanced power cycles

    DOE PAGES

    Sakadjian, B.; Hu, S.; Maryamchik, M.; ...

    2015-06-05

    Solar Particle Receivers (SPR) are under development to drive concentrating solar plants (CSP) towards higher operating temperatures to support higher efficiency power conversion cycles. The novel high temperature SPR-based CSP system uses solid particles as the heat transfer medium (HTM) in place of the more conventional fluids such as molten salt or steam used in current state-of-the-art CSP plants. The solar particle receiver (SPR) is designed to heat the HTM to temperatures of 800 °C or higher which is well above the operating temperatures of nitrate-based molten salt thermal energy storage (TES) systems. The solid particles also help overcome somemore » of the other challenges associated with molten salt-based systems such as freezing, instability and degradation. The higher operating temperatures and use of low cost HTM and higher efficiency power cycles are geared towards reducing costs associated with CSP systems. This paper describes the SPR-based CSP system with a focus on the fluidized-bed (FB) heat exchanger and its integration with various power cycles. Furthermore, the SPR technology provides a potential pathway to achieving the levelized cost of electricity (LCOE) target of $0.06/kWh that has been set by the U.S. Department of Energy's SunShot initiative.« less

  11. Impact of SolarSmart Subdivisions on SMUD's Distribution System

    SciTech Connect

    McNutt, P.; Hambrick, J.; Keesee, M.; Brown, D.

    2009-07-01

    This study analyzes the distribution impacts of high penetrations of grid-integrated renewable energy systems, specifically photovoltaic (PV) equipped SolarSmart Homes found in the Anatolia III Residential Community.

  12. Solar Successes: The Best of Today's Energy Efficient Homes

    SciTech Connect

    2008-01-01

    This is a brochure developed specifically for residential home builders. It provides information on basic financial factors and additional resources to consider when incorporating solar technologies into building plans.

  13. Property Tax Assessments as a Finance Vehicle for Residential PV Installations: Opportunities and Potential Limitations

    SciTech Connect

    Bolinger, Mark A; Bolinger, Mark

    2008-02-01

    than a more-traditional credit vehicle, to recover both system and administrative costs. As discussed in more detail later, this seemingly innovative approach has a number of features that should appeal to PV owners, including: long-term, fixed-cost, attractive financing; loans that are tied to the tax capacity of the property rather than to the owner's credit standing; a repayment obligation that transfers along with the sale of the property; and a potential ability to deduct the repayment obligation from Federal taxable income, as part of the local property tax deduction. For these reasons, Berkeley's program--which was first announced on October 23, 2007--has received considerable nationwide attention in both the trade and general press. Since the announcement, cities from throughout California and the broader U.S. have expressed keen interest in the possibility of replicating this type of program. In California alone, the cities of Santa Cruz, Santa Monica, and Palm Desert are all reportedly considering similar programs, while the city of San Francisco has recently announced its own program, portions of which closely parallel Berkeley's approach. Berkeley's Proposed PV Program In addition, a bill (AB 811) that would authorize all cities (not just 'charter cities' like Berkeley) in California to create this type of program was approved by the California General Assembly on January 29, 2008 and passed on to the State Senate for consideration. That local governments from across California and the broader US are so genuinely excited about the prospect of supporting the installation of residential PV in their communities through this type of program is no doubt an interesting development. Given, however, the potential for such programs to negatively interact with the residential solar ITC, it is important to evaluate the financial attractiveness of this specific type of loan program, particularly in advance of any broader state- or nation-wide 'rollout'. This case study

  14. Photovoltaics: Solar electric power systems

    NASA Astrophysics Data System (ADS)

    1980-02-01

    The operation and uses of solar cells and the National Photovoltaic Program are briefly described. Eleven DOE photovoltaic application projects are described including forest lookout towers; Wilcox Memorial Hospital in Hawaii; WBNO daytime AM radio station; Schuchuli Indian Village; Meade, Nebraska, agricultural experiment; Mt. Laguna Air Force Station; public schools and colleges; residential applications; and Sea World of Florida.

  15. Photovoltaics: solar electric power systems

    SciTech Connect

    1980-02-01

    The operation and uses of solar cells and the National Photovoltaic Program are briefly described. Eleven DOE photovoltaic application projects are described including forest lookout towers; Wilcox Memorial Hospital in Hawaii; WBNO daytime AM radio station; Schuchuli Indian Village; Meade, Nebraska, agricultural experiment; Mt. Laguna Air Force Station; public schools and colleges; residential applications; and Sea World of Florida. (WHK)

  16. Solar energy storage and utilization

    NASA Technical Reports Server (NTRS)

    Yuan, S. W.; Bloom, A. M.

    1976-01-01

    A method of storing solar energy in the ground for heating residential buildings is described. The method would utilize heat exchanger pipes with a circulating fluid to transfer the energy beneath the surface as well as to extract the stored energy.

  17. Solar Job Related Training.

    ERIC Educational Resources Information Center

    Lennox Industries, Inc., Dallas, TX.

    This book contains comprehensive instruction in design, installation, and service procedures for typical solar space heat and domestic hot water systems. The book is comprised of five major sections. Solar Systems: Past and Present presents a brief look at how far solar technology has advanced. Included in this section are descriptions of over…

  18. Summary of flat-plate solar array project documentation: Abstracts of published documents, 1975-1986, revision 1

    NASA Technical Reports Server (NTRS)

    Phillips, M. J.

    1986-01-01

    Abstracts of final reports, or the latest quarterly or annual, of the Flat-Plate Solar Array (FSA) Project Contractor of Jet Propulsion Laboratory (JPL) in-house activities are presented. Also presented is a list of proceedings and publications, by author, of work connected with the project. The aim of the program has been to stimulate the development of technology that will enable the private sector to manufacture and widely use photovoltaic systems for the generation of electricity in residential, commercial, industrial, and Government applications at a cost per watt that is competitive with utility generated power. FSA Project activities have included the sponsoring of research and development efforts in silicon refinement processes, advanced silicon sheet growth techniques, higher efficiency solar cells, solar cell/module fabrication processes, encapsulation, module/array engineering and reliability, and economic analyses.

  19. Feasibility study: management of selected aspects of the advanced Solar Thermal Technology Program by a University consortium. Final report, June 1, 1980-February 28, 1981

    SciTech Connect

    Hildebrandt, A.F.; Brown, J.H.U.

    1981-02-01

    To increase the involvement of universities and advanced technology industries in task-oriented supporting research for the Solar Thermal Energy System (STES) program, organizational issues are considered. A generic and discipline focused program is considered which could provide applied research capabilities for all elements in the STES program. A management structure is presented which is organized around the management and research capabilities of universities. The proposed organization structure is designed to effectively plan, implement, and manage an applied research program dedicated to providing research support for and in coordination with the STES program. The chief aim is to enhance and expand the involvement of universities in the STES program through one or two university management and through the active participation by other universities and industries in an executive advisory board. A large number of consortia development studies were considered and university and industry views were consolidated. A two university team management approach is believed to have distinct advantages.

  20. Residential mobility, well-being, and mortality.

    PubMed

    Oishi, Shigehiro; Schimmack, Ulrich

    2010-06-01

    We tested the relation between residential mobility and well-being in a sample of 7,108 American adults who were followed for 10 years. The more residential moves participants had experienced as children, the lower the levels of well-being as adults. As predicted, however, the negative association between the number of residential moves and well-being was observed among introverts but not among extraverts. We further demonstrated that the negative association between residential mobility and well-being among introverts was explained by the relative lack of close social relationships. Finally, we found that introverts who had moved frequently as children were more likely to have died during the 10-year follow-up. Among extraverts, childhood residential mobility was unrelated to their mortality risk as adults. These findings indicate that residential moves can be a risk factor for introverts and that extraversion can be an interpersonal resource for social relationships and well-being in mobile societies.