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Sample records for photovoltaic domestic field

  1. 48 CFR 225.7017 - Utilization of domestic photovoltaic devices.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Utilization of domestic photovoltaic devices. 225.7017 Section 225.7017 Federal Acquisition Regulations System DEFENSE ACQUISITION... photovoltaic devices....

  2. 48 CFR 225.7017 - Utilization of domestic photovoltaic devices.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Utilization of domestic photovoltaic devices. 225.7017 Section 225.7017 Federal Acquisition Regulations System DEFENSE ACQUISITION... photovoltaic devices....

  3. 48 CFR 225.7017 - Utilization of domestic photovoltaic devices.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 3 2014-10-01 2014-10-01 false Utilization of domestic photovoltaic devices. 225.7017 Section 225.7017 Federal Acquisition Regulations System DEFENSE ACQUISITION... photovoltaic devices....

  4. AC photovoltaic module magnetic fields

    SciTech Connect

    Jennings, C.; Chang, G.J.; Reyes, A.B.; Whitaker, C.M.

    1997-12-31

    Implementation of alternating current (AC) photovoltaic (PV) modules, particularly for distributed applications such as PV rooftops and facades, may be slowed by public concern about electric and magnetic fields (EMF). This paper documents magnetic field measurements on an AC PV module, complementing EMF research on direct-current PV modules conducted by PG and E in 1993. Although not comprehensive, the PV EMF data indicate that 60 Hz magnetic fields (the EMF type of greatest public concern) from PV modules are comparable to, or significantly less than, those from household appliances. Given the present EMF research knowledge, AC PV module EMF may not merit considerable concern.

  5. An investigation of photovoltaic powered pumps in direct solar domestic hot water systems

    SciTech Connect

    Al-Ibrahim, A.M.; Klein, S.A.; Mitchell, J.W.; Beckman, W.A.

    1996-09-01

    The performance of photovoltaic powered pumps in direct solar domestic hot water (PV-SDHW) systems has been studied. The direct PV- SDHW system employs a photovoltaic array, a separately excited DC- motor, a centrifugal pump, a thermal collector, and a storage tank. A search methodology for an optimum PV-SDHW system configuration has been proposed. A comparison is made between the long-term performance of a PV-SDHW system and a conventional SDHW system operating under three control schemes. The three schemes are: an ON-OFF flow controlled SDHW system operating at the manufacturer-recommended constant flow rate, and a linear proportional flow controlled SDHW system with the flow proportional to the solar radiation operating under an optimum proportionality. 13 refs., 6 figs.

  6. Optimized low-cost-array field designs for photovoltaic systems

    SciTech Connect

    Post, H.N.; Carmichael, D.C.; Castle, J.A.

    1982-01-01

    As manager of the US Department of Energy Photovoltaic Systems Definition Project, Sandia National Laboratories is engaged in a comprehensive program to define and develop array field subsystems which can achieve the lowest possible lifecycle costs. The major activity of this program is described, namely, the design and development of optimized, modular array fields for photovoltaic (PV) systems. As part of this activity, design criteria and performance requirements for specific array subsystems including support structures, foundations, intermodule connections, field wiring, lightning protection, system grounding, site preparation, and monitoring and control have been defined and evaluated. Similarly, fully integrated flat-panel array field designs, optimized for lowest lifecycle costs, have been developed for system sizes ranging from 20 to 500 kW/sub p/. Key features, subsystem requirements, and projected costs for these array field designs are presented and discussed.

  7. Conjugated ionomers for photovoltaic applications: electric field driven charge separation in organic photovoltaics. Final Technical report

    SciTech Connect

    Lonergan, Mark

    2015-05-29

    Final technical report for Conjugated ionomers for photovoltaic applications, electric field driven charge separation in organic photovoltaics. The central goal of the work we completed was been to understand the photochemical and photovoltaic properties of ionically functionalized conjugated polymers (conjugated ionomers or polyelectrolytes) and energy conversion systems based on them. We primarily studied two classes of conjugated polymer interfaces that we developed based either upon undoped conjugated polymers with an asymmetry in ionic composition (the ionic junction) or doped conjugated polymers with an asymmetry in doping type (the p-n junction). The materials used for these studies have primarily been the polyacetylene ionomers. We completed a detailed study of p-n junctions with systematically varying dopant density, photochemical creation of doped junctions, and experimental and theoretical work on charge transport and injection in polyacetylene ionomers. We have also completed related work on the use of conjugated ionomers as interlayers that improve the efficiency or organic photovoltaic systems and studied several important aspects of the chemistry of ionically functionalized semiconductors, including mechanisms of so-called "anion-doping", the formation of charge transfer complexes with oxygen, and the synthesis of new polyfluorene polyelectrolytes. We also worked worked with the Haley group at the University of Oregon on new indenofluorene-based organic acceptors.

  8. Field trial of rural solar photovoltaic system

    NASA Astrophysics Data System (ADS)

    Basu, P.; Mukhopadhyay, K.; Banerjee, T.; Das, S.; Saha, H.

    Experience, costs, and performance of photovoltaic (PV) systems set up in a remote Indian village to power an adult literacy center and an irrigation pump are described. The center was furnished with a 14-module, 200 W array to power a television and three fluorescent lamps. The pumping installation has 20 modules for a 300 W output directly coupled to a 300-W dc pump motor. Data were gathered on the open circuit voltage, short circuit current, specific gravity of the battery fluid, degradation of the cells, nominal operating temperature of the cells, load currents, Amp-hours, water flow rate (pump), and the static head and draw down rate (pump). Monitoring of the array performances in the dusty environment showed that once/week cleaning is necessary. Al-substrates cracked at the center installation and sealant evaporation caused condensation which degraded the light transmissivity and thereby the short-circuit current of the modules. The combination of low-efficiency (5 pct) cells and cheap labor demonstrated economic operation without high-efficiency cells.

  9. Magnetic field survey at PG&E photovoltaic sites

    SciTech Connect

    Chang, G.J.; Jennings, C.

    1994-08-01

    Public awareness has aroused concerns over the possible effects of magnetic fields on human health. While research continues to determine if magnetic fields do, in fact, affect human health, concerned individuals are requesting data on magnetic field sources in their environments to base personal decisions about limiting their exposure to these sources. Timely acceptance and implementation of photovoltaics (PV), particularly for distributed applications such as PV rooftops, windows, and vehicles, may be hampered by the lack of PV magnetic field data. To address this situation, magnetic flux density was measured around equipment at two PVUSA (Photovoltaics for Utility Scale Applications) project sites in Kerman and Davis, California. This report documents the data and compares the PV magnetic fields with published data on more prevalent magnetic field sources. Although not comprehensive, electric and magnetic field (EMF) data taken at PVUSA indicate that 60-Hz magnetic fields (the EMF type of greatest public concern) are significantly less for PV arrays than for household applications. Therefore, given the present EMF research knowledge, PV array EMF may not merit considerable concern. The PV system components exhibiting significant AC magnetic fields are the transformers and power conditioning units (PCUs). However, the AC magnetic fields associated with these components are localized and are not detected at PV system perimeters. Concern about transformer and PCU EMF would apply to several generation and storage technologies.

  10. Analysis techniques used on field degraded photovoltaic modules

    SciTech Connect

    Hund, T.D.; King, D.L.

    1995-09-01

    Sandia National Laboratory`s PV System Components Department performs comprehensive failure analysis of photovoltaic modules after extended field exposure at various sites around the world. A full spectrum of analytical techniques are used to help identify the causes of degradation. The techniques are used to make solder fatigue life predictions for PV concentrator modules, identify cell damage or current mismatch, and measure the adhesive strength of the module encapsulant.

  11. Photovoltaics

    SciTech Connect

    Deb, S.K.

    1985-01-01

    Photovoltaics, the direct conversion of sunlight into electrical energy, may be the best hope for a relatively clean, secure, and inexhaustible source of energy for the future. To stimulate the growth of this technology as a viable energy supply option, considerable research and development has been directed, in both the private and public sectors, to a variety of materials and devices. The technology has sufficiently matured in recent years to be seriously considered as an alternative to conventional energy sources. Despite phenomenal advances in energy conversion efficiencies, many problems still remain to be solved. It is timely, therefore, to review various technological options available. This review critically assesses the status and promise of this emerging technology by a group of experts, each of whom has presented an extended invited paper on his specific field of expertise. This collection of presentations is intended to be an authoritative review of the technology including its developments, current status, and projections for future direction. The content of this review was carefully chosen to represent most of the leading state-of-the-art technologies; these are divided into four areas: (i) a general overview and discussion of silicon technology; (ii) high efficiency multijunction solar cells; (iii) amorphous silicon solar cells; and (iv) thin film compound semiconductors.

  12. Photovoltaics

    NASA Astrophysics Data System (ADS)

    Seippel, R. G.

    This book attempts to provide the reader with a cursory look at solar energy from a quarry of quartz to a sophisticated solar system. The progression of the theories of light is discussed along with the progression of photoelectricity, light rays, the optical spectrum, light reception, photodetection, aspects of photometry and radiometry, preferred terms in radiometric measurement, semiconductor physics, and light energy availability. Other subjects explored are related to manufacturing processes, photovoltaic materials, crystal growing, slicing techniques, wafer finishing, solar cell fabrication, photovoltaic cell types, concentrators, module fabrication, problems of quality assurance, photovoltaic systems, and the photovoltaics hierarchy. Attention is given to the polycrystalline cell, insulator cells, cadmium sulfide cells, amorphous silicon cells, an electrochemical cell, and the low-cost solar array project.

  13. Low cost modular designs for photovoltaic array fields

    SciTech Connect

    Post, H.N.; Carmichael, D.C.; Castle, J.A.

    1982-01-01

    Described are the design and development of optimized, modular array fields for photovoltaic (PV) systems. Design criteria and performance requirements have been defined and evaluated for specific array subsystems. These subsystems include support structures, foundations, intermodule connection, field wiring, lightning protection, system grounding, site preparation, and monitoring and control. Fully integrated flat-panel array-field designs, optimized for lowest life-cycle costs, have been developed for systems ranging in size from 20 to 500 kW/sub p/. These designs are applicable for near-term implementation (1982 to 1983) and reduce the array-field balance-of-system (BOS) costs to a fraction of previous costs. Key features, subsystem requirements, and projected costs are presented and discussed.

  14. Photovoltaic-Powered Vaccine Refrigerator: Freezer Systems Field Test Results

    NASA Technical Reports Server (NTRS)

    Ratajczak, A. F.

    1985-01-01

    A project to develop and field test photovoltaic-powered refrigerator/freezers suitable for vaccine storage was undertaken. Three refrigerator/freezers were qualified; one by Solar Power Corp. and two by Solvolt. Follow-on contracts were awarded for 19 field test systems and for 10 field test systems. A total of 29 systems were installed in 24 countries between October 1981 and October 1984. The project, systems descriptions, installation experiences, performance data for the 22 systems for which field test data was reported, an operational reliability summary, and recommendations relative to system designs and future use of such systems are explained. Performance data indicate that the systems are highly reliable and are capable of maintaining proper vaccine storage temperatures in a wide range of climatological and user environments.

  15. 76 FR 78858 - Defense Federal Acquisition Regulation Supplement; Utilization of Domestic Photovoltaic Devices...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-20

    .... Photovoltaic devices produce direct current electricity from sunlight, which can be used to provide power to... of the ] power for the full economic life of the equipment equates to ownership and would then... the power generated from the device (could be under any of the scenarios identified in (1) or...

  16. Wind loads on flat plate photovoltaic array fields

    NASA Technical Reports Server (NTRS)

    Miller, R. D.; Zimmerman, D. K.

    1981-01-01

    The results of an experimental analysis (boundary layer wind tunnel test) of the aerodynamic forces resulting from winds acting on flat plate photovoltaic arrays are presented. Local pressure coefficient distributions and normal force coefficients on the arrays are shown and compared to theoretical results. Parameters that were varied when determining the aerodynamic forces included tilt angle, array separation, ground clearance, protective wind barriers, and the effect of the wind velocity profile. Recommended design wind forces and pressures are presented, which envelop the test results for winds perpendicular to the array's longitudinal axis. This wind direction produces the maximum wind loads on the arrays except at the array edge where oblique winds produce larger edge pressure loads. The arrays located at the outer boundary of an array field have a protective influence on the interior arrays of the field. A significant decrease of the array wind loads were recorded in the wind tunnel test on array panels located behind a fence and/or interior to the array field compared to the arrays on the boundary and unprotected from the wind. The magnitude of this decrease was the same whether caused by a fence or upwind arrays.

  17. From forest to field: Perennial fruit crop domestication

    Technology Transfer Automated Retrieval System (TEKTRAN)

    • Premise of the study. Understanding of plant domestication and evolution are enhanced by archaeological and genetic analyses of seed-propagated annual crops. Domestication of perennial plants may reveal how genes and genomes evolve in long-lived species and how perennial plants respond to selec...

  18. Magnetic field effects in a polymer/fullerene blend photovoltaic cell

    NASA Astrophysics Data System (ADS)

    Jang, Hyuk-Jae; Basham, James I.; Gundlach, David J.; Richter, Curt A.

    Organic photovoltaic (OPV) systems based on blends of conjugated polymers and fullerene derivatives have shown great promise for low-cost and efficient photovoltaic applications. Recent findings suggest that a weak external magnetic field can disturb the spin configuration of excited states and subsequently change properties of OPV cells such as photocurrent. These changes are referred to as magnetic field effects (MFEs). In order to have a better understanding of the underlying mechanisms responsible for the MFEs in polymer/fullerene blend photovoltaic systems, we fabricated poly-3-hexylthiophene (P3HT):phenyl-C61-butyric acid methyl ester (PC61BM) cells and carried out photovoltaic device performance and impedance spectroscopy measurements with and without an externally applied magnetic field. A significant reduction in short circuit current (JSC) as well as open circuit voltage (VOC) was observed with an applied magnetic field of a 0.1 tesla compared to those measured without a magnetic field under the same intensity of illumination. Impedance spectroscopy data gives insights into the influence of an external magnetic field on charge generation and recombination near normal photovoltaic operating conditions.

  19. Design and field performance of the KENETECH photovoltaic inverter system

    SciTech Connect

    Behnke, M.R.

    1995-11-01

    KENETECH Windpower has recently adapted the power conversion technology developed for the company`s variable speed wind turbine to grid-connected photovoltaic applications. KENETECH PV inverter systems are now in successful operation at the Sacramento Municipal Utility District`s (SMUD) Hedge Substation and the PVUSA-Davis site, with additional systems scheduled to be placed into service by the end of 1995 at SMUD, the New York Power Authority, Xerox Corporation`s Clean Air Now project, and the Georgia Tech Aquatic Center. The features of the inverter are described.

  20. Wind loads on flat plate photovoltaic array fields (nonsteady winds)

    NASA Technical Reports Server (NTRS)

    Miller, R. D.; Zimmerman, D. K.

    1981-01-01

    Techniques to predict the dynamic response and the structural dynamic loads of flat plate photovoltaic arrays due to wind turbulence were analyzed. Guidelines for use in predicting the turbulent portion of the wind loading on future similar arrays are presented. The dynamic response and the loads dynamic magnification factor of the two array configurations are similar. The magnification factors at a mid chord and outer chord location on the array illustrated and at four points on the chord are shown. The wind tunnel test experimental rms pressure coefficient on which magnification factors are based is shown. It is found that the largest response and dynamic magnification factor occur at a mid chord location on an array and near the trailing edge. A technique employing these magnification factors and the wind tunnel test rms fluctuating pressure coefficients to calculate design pressure loads due to wind turbulence is presented.

  1. Development of low-cost modular designs for photovoltaic array fields

    SciTech Connect

    Noel, G.T.; Carmichael, D.C.

    1985-05-01

    A low-cost modular photovoltaic array field design developed for commercial/industrial installations is discussed. Key features of the design include minimum site preparation requirements, circuit designs which result in low life-cycle maintenance costs, low cost easily installed support structures, and economical approaches to lightning protection, grounding and electromagnetic interference (EMI) suppression.

  2. Wind Loads on Flat Plate Photovoltaic Array Fields

    NASA Technical Reports Server (NTRS)

    Miller, R.; Zimmerman, D.

    1979-01-01

    The aerodynamic forces resulting from winds acting on flat plate photovoltaic arrays were investigated. Local pressure distributions and total aerodynamic forces on the arrays are shown. Design loads are presented to cover the conditions of array angles relative to the ground from 20 deg to 60 deg, variable array spacings, a ground clearance gap up to 1.2 m (4 ft) and array slant heights of 2.4 m (8 ft) and 4.8 m (16 ft). Several means of alleviating the wind loads on the arrays are detailed. The expected reduction of the steady state wind velocity with the use of fences as a load alleviation device are indicated to be in excess of a factor of three for some conditions. This yields steady state wind load reductions as much as a factor of ten compared to the load incurred if no fence is used to protect the arrays. This steady state wind load reduction is offset by the increase in turbulence due to the fence but still an overall load reduction of 2.5 can be realized. Other load alleviation devices suggested are the installation of air gaps in the arrays, blocking the flow under the arrays and rounding the edges of the array. A wind tunnel test plan to supplement the theoretical study and to evaluate the load alleviation devices is outlined.

  3. The enteritis complex in domestic rabbits: A field study

    PubMed Central

    Percy, Dean H.; Muckle, C. Anne; Hampson, Robert J.; Brash, Marina L.

    1993-01-01

    A study of the causative agents of enteritis in domestic rabbits from 44 different accessions is described. In descending order of frequency, the organisms most commonly demonstrated were intestinal and hepatic coccidia (Eimeria species), Escherichia coli, Clostridium spp., Salmonella, Bacillus piliformis, and rotavirus. The species of Eimeria identified included those moderately pathogenic and coccidia of low pathogenicity. Using seven antisera against known enterpathogenic strains of E. coli, only one strain, O15, was identified in three cases. Clostridium perfringens or C. spiroforme was demonstrated in the intestinal contents in 11 cases, and lesions compatible with clostridial enteropathy were identified on gross and histopathology. In a serological survey, over 50% of 200 fryer rabbits submitted to Ontario abattoirs and of animals from commercial rabbitries had detectable antibody to rotavirus, indicating the widespread distribution of rotaviral infections in this species. In the cases of enteritis studied, two or more potentially pathogenic organisms were frequently identified, emphasizing that several different organisms may be acting in concert to produce clinical disease. ImagesFigure 1. PMID:17424177

  4. Temperature-Dependent Polarization in Field-Effect Transport and Photovoltaic Measurements of Methylammonium Lead Iodide.

    PubMed

    Labram, John G; Fabini, Douglas H; Perry, Erin E; Lehner, Anna J; Wang, Hengbin; Glaudell, Anne M; Wu, Guang; Evans, Hayden; Buck, David; Cotta, Robert; Echegoyen, Luis; Wudl, Fred; Seshadri, Ram; Chabinyc, Michael L

    2015-09-17

    While recent improvements in the reported peak power conversion efficiency (PCE) of hybrid organic-inorganic perovskite solar cells have been truly astonishing, there are many fundamental questions about the electronic behavior of these materials. Here we have studied a set of electronic devices employing methylammonium lead iodide ((MA)PbI3) as the active material and conducted a series of temperature-dependent measurements. Field-effect transistor, capacitor, and photovoltaic cell measurements all reveal behavior consistent with substantial and strongly temperature-dependent polarization susceptibility in (MA)PbI3 at temporal and spatial scales that significantly impact functional behavior. The relative PCE of (MA)PbI3 photovoltaic cells is observed to reduce drastically with decreasing temperature, suggesting that such polarization effects could be a prerequisite for high-performance device operation. PMID:26722725

  5. Physical characterization of cadmium telluride/cadmium sulfide photovoltaics: Defects, fields, and micrononuniformities

    NASA Astrophysics Data System (ADS)

    Shvydka, Diana

    Recent advances in large area thin-film photovoltaic manufacturing have raised a number of problems related to the physical parameters and processes behind the device efficiency and stability. The characteristics of interest include the defect spectra and related optical absorption, the built-in electric field distribution, the degree of lateral uniformity of the device, and the device stability. Established in this thesis is a set of techniques appropriate for the physical characterization of the above features in CdTe/CdS solar cells, addressing the issues of device spectra vs. energy (as revealed in the optical absorption, photoluminescence (PL), and admittance spectroscopy); the electric field distribution analyzed by means of bias dependent PL, and, indirectly, by capacitance measurements; device lateral resistivity and uniformity, through the phenomenon of nonlocal optical response and PL mapping; local parameter fluctuations as appear in virtually all of the above cases. The most important physical conclusions made are: energy spectra of polycrystalline CdTe based photovoltaics combine the features of crystalline materials, such as identifiable point defects, and amorphous materials, which exhibit continuous spectra of localized states; the concept of a single-defect (elemental) capacitance is for the first time defined and applied to estimate the density of states in polycrystalline p-n junctions; a phenomenon of bias-dependent PL in CdTe based photovoltaics is for the first time observed and modeled; a new phenomenon of nonlocal photovoltaic response is observed and interpreted. The results suggest several practical applications, such as: absorption and PL measurements as a diagnostic tool for monitoring the CdCl2, quality of treatments; admittance spectroscopy techniques to diagnose the material quality and degradation through its defect spectra and concentration; bias-dependent PL as a sensitive nondestructive accelerated life testing tool; nonlocal PV

  6. Electric field measurement of organic photovoltaic cell model using electrooptic probe

    NASA Astrophysics Data System (ADS)

    Saito, Ryo; Yabe, Yoko; Suzuki, Akito; Shinagawa, Mitsuru; Sugino, Hiroyuki; Katsuyama, Jun; Matsumoto, Yoshinori

    2016-09-01

    In this paper, we describe the use of a transverse electrooptic probe to measure the electric field of an organic photovoltaic (OPV) cell model. It is necessary to measure the voltage of each OPV cell in order to diagnose failure of the OPV. An electric field is generated by the OPV cell voltage, so measuring the electric field is effective for obtaining a failure diagnosis of the OPV. We use a transverse electrooptic probe as an instrumentation tool for measuring the electric field over the OPV. We confirmed the principle of superposition for the electric field strength from each OPV cell model. These results show that the calibration of each OPV cell voltage can be accomplished by measuring the electric field strength over the OPV cells.

  7. Photovoltaic module performance and durability following long-term field exposure

    SciTech Connect

    Ellibee, D.E.; Hansen, B.R.; King, D.L.; Kratochvil, J.A.; Quintana, M.A.

    1998-09-08

    Our investigations of both new and field-aged photovoltaic modules have indicated that, in general, today's commercially available modules area highly reliable product. However, by using new test procedures, subtle failure mechanisms have also been identified that must be addressed in order to achieve 30-year module lifetimes. This paper summarizes diagnostic test procedures, results, and implications of in-depth investigations of the performance and durability characteristics of commercial modules after long-term field exposure. A collaborative effort with U.S. module manufacturers aimed at achieving 30-year module lifetimes is also described.

  8. Photovoltaic concentrator optical system design: Solar energy engineering from physics to field

    NASA Astrophysics Data System (ADS)

    Coughenour, Blake Michael

    This dissertation describes the design, development, and field validation of a concentrator photovoltaic (CPV) solar energy system. The challenges of creating a highly efficient yet low-cost system architecture come from many sources. The solid-state physics of photovoltaic devices present fundamental limits to photoelectron conversion efficiency, while the electrical and thermal characteristics of widely available materials limit the design arena. Furthermore, the need for high solar spectral throughput, evenly concentrated sunlight, and tolerance to off-axis pointing places strict illumination requirements on the optical design. To be commercially viable, the cost associated with all components must be minimized so that when taken together, the absolute installed cost of the system in kWh is lower than any other solar energy method, and competitive with fossil fuel power generation. The work detailed herein focuses specifically on unique optical design and illumination concepts discovered when developing a viable commercial CPV system. By designing from the ground up with the fundamental physics of photovoltaic devices and the required system tolerances in mind, a select range of optical designs are determined and modeled. Component cost analysis, assembly effort, and development time frame further influence design choices to arrive at a final optical system design. When coupled with the collecting mirror, the final optical hardware unit placed at the focus generates more than 800W, yet is small and lightweight enough to hold in your hand. After fabrication and installation, the completed system's illumination, spectral, and thermal performance is validated with on-sun operational testing.

  9. Optimization of Electric Power Systems for Off-Grid Domestic Applications: An Argument for Wind/Photovoltaic Hybrids

    SciTech Connect

    Jennings, W.; Green, J.

    2001-01-01

    The purpose of this research was to determine the optimal configuration of home power systems relevant to different regions in the United States. The hypothesis was that, regardless of region, the optimal system would be a hybrid incorporating wind technology, versus a photovoltaic hybrid system without the use of wind technology. The method used in this research was HOMER, the Hybrid Optimization Model for Electric Renewables. HOMER is a computer program that optimizes electrical configurations under user-defined circumstances. According to HOMER, the optimal system for the four regions studied (Kansas, Massachusetts, Oregon, and Arizona) was a hybrid incorporating wind technology. The cost differences between these regions, however, were dependent upon regional renewable resources. Future studies will be necessary, as it is difficult to estimate meteorological impacts for other regions.

  10. Some tests of flat plate photovoltaic module cell temperatures in simulated field conditions

    NASA Technical Reports Server (NTRS)

    Griffith, J. S.; Rathod, M. S.; Paslaski, J.

    1981-01-01

    The nominal operating cell temperature (NOCT) of solar photovoltaic (PV) modules is an important characteristic. Typically, the power output of a PV module decreases 0.5% per deg C rise in cell temperature. Several tests were run with artificial sun and wind to study the parametric dependencies of cell temperature on wind speed and direction and ambient temperature. It was found that the cell temperature is extremely sensitive to wind speed, moderately so to wind direction and rather insensitive to ambient temperature. Several suggestions are made to obtain data more typical of field conditions.

  11. Photovoltaics industry profile

    SciTech Connect

    1980-10-01

    A description of the status of the US photovoltaics industry is given. Principal end-user industries are identified, domestic and foreign market trends are discussed, and industry-organized and US government-organized trade promotion events are listed. Trade associations and trade journals are listed, and a photovoltaic product manufacturers list is included. (WHK)

  12. Development of a building block design of modular photovoltaic concentrator array fields

    SciTech Connect

    Carmichael, D.C.; Alexander, G.; Noel, G.T.; Scurlock, L.D.; Huss, W.R.; Stickford, G.H.

    1983-08-01

    To reduce the balance-of-system (BOS) costs and site-specific design costs for photovoltaic concentrator array fields, a modular Building Block design has been developed for installing array fields of each of two available concentrator collectors. The array-field subsystems and requirements incorporated in the design analyses include site preparation, foundations, electrical wiring, grounding, lightning protection, electromagnetic interference provisions, and tracking and controls. The Building Block designs developed minimize these array-field BOS costs and serve as standardized units to be used in multiples to construct array fields of various sizes. The detailed drawings and construction specifications prepared for the designs require only minimal design modification and cost for adaption to a specific site and application. The two concentrator collectors for which the modular array-field designs were developed are the linear-focus Fresnel-lens array manufactured by E-Systems, Inc., and the point-focus Fresnel-lens array manufactured by Martin Marietta Aerospace Corporation. Both designs are two-axis tracking and passively cooled. The developed Building Block designs are immediately applicable and reduce the array-field BOS costs and site-specific design costs to a fraction of those experienced in previous installations. The estimated array-field BOS costs (in 1982 dollars) using these modular designs are $0.78/W for the modular field based on the E-Systems array and $1.18/W for the modular field based on the Martin-Marietta array.

  13. Graphene-based photovoltaic cells for near-field thermal energy conversion.

    PubMed

    Messina, Riccardo; Ben-Abdallah, Philippe

    2013-01-01

    Thermophotovoltaic devices are energy-conversion systems generating an electric current from the thermal photons radiated by a hot body. While their efficiency is limited in far field by the Schockley-Queisser limit, in near field the heat flux transferred to a photovoltaic cell can be largely enhanced because of the contribution of evanescent photons, in particular for a source supporting a surface mode. Unfortunately, in the infrared where these systems operate, the mismatch between the surface-mode frequency and the semiconductor gap reduces drastically the potential of this technology. In this paper we propose a modified thermophotovoltaic device in which the cell is covered by a graphene sheet. By discussing the transmission coefficient and the spectral properties of the flux, we show that both the cell efficiency and the produced current can be enhanced, paving the way to promising developments for the production of electricity from waste heat. PMID:23474891

  14. Multi angle laser light scattering evaluation of field exposed thermoplastic photovoltaic encapsulant materials

    DOE PAGESBeta

    Kempe, Michael D.; Miller, David C.; Wohlgemuth, John H.; Kurtz, Sarah R.; Moseley, John M.; Nobles, Dylan L.; Stika, Katherine M.; Brun, Yefim; Samuels, Sam L.; Shah, Qurat Annie; et al

    2016-01-08

    As creep of polymeric materials is potentially a safety concern for photovoltaic modules, the potential for module creep has become a significant topic of discussion in the development of IEC 61730 and IEC 61215. To investigate the possibility of creep, modules were constructed, using several thermoplastic encapsulant materials, into thin-film mock modules and deployed in Mesa, Arizona. The materials examined included poly(ethylene)-co-vinyl acetate (EVA, including formulations both cross-linked and with no curing agent), polyethylene/polyoctene copolymer (PO), poly(dimethylsiloxane) (PDMS), polyvinyl butyral (PVB), and thermoplastic polyurethane (TPU). The absence of creep in this experiment is attributable to several factors of which themore » most notable one was the unexpected cross-linking of an EVA formulation without a cross-linking agent. It was also found that some materials experienced both chain scission and cross-linking reactions, sometimes with a significant dependence on location within a module. The TPU and EVA samples were found to degrade with cross-linking reactions dominating over chain scission. In contrast, the PO materials degraded with chain scission dominating over cross-linking reactions. Furthermore, we found no significant indications that viscous creep is likely to occur in fielded modules capable of passing the qualification tests, we note that one should consider how a polymer degrades, chain scission or cross-linking, in assessing the suitability of a thermoplastic polymer in terrestrial photovoltaic applications.« less

  15. Electromagnetic Fields Associated with Commercial Solar Photovoltaic Electric Power Generating Facilities.

    PubMed

    Tell, R A; Hooper, H C; Sias, G G; Mezei, G; Hung, P; Kavet, R

    2015-01-01

    The southwest region of the United States is expected to experience an expansion of commercial solar photovoltaic generation facilities over the next 25 years. A solar facility converts direct current generated by the solar panels to three-phase 60-Hz power that is fed to the grid. This conversion involves sequential processing of the direct current through an inverter that produces low-voltage three-phase power, which is stepped up to distribution voltage (∼12 kV) through a transformer. This study characterized magnetic and electric fields between the frequencies of 0 Hz and 3 GHz at two facilities operated by the Southern California Edison Company in Porterville, CA and San Bernardino, CA. Static magnetic fields were very small compared to exposure limits established by IEEE and ICNIRP. The highest 60-Hz magnetic fields were measured adjacent to transformers and inverters, and radiofrequency fields from 5-100 kHz were associated with the inverters. The fields measured complied in every case with IEEE controlled and ICNIRP occupational exposure limits. In all cases, electric fields were negligible compared to IEEE and ICNIRP limits across the spectrum measured and when compared to the FCC limits (≥0.3 MHz). PMID:26023811

  16. Electroabsorption and oppositely directed built-in fields in a photovoltaic organic heterostructure

    SciTech Connect

    Blinov, L. M. Lazarev, V. V.; Yudin, S. G.

    2013-11-15

    The directions and intensities of local electric fields spontaneously built into organic nanoscale structures of Schottky-diode type, indium tin oxide (ITO)-CuPc-Al and ITO-C{sub 60}-Al, with donor and acceptor layers of copper phthalocyanine (CuPc) and fullerene (C{sub 60}) have been investigated using an improved spectral electroabsorption technique. It is established that, in the absence of external field and illumination, the built-in fields in the bulk of these structures are directed differently: from Al to ITO in the case of CuPc and from ITO to Al in the case of C{sub 6}0. The best studied photovoltaic heterostructure ITO-CuPc-C{sub 6}0-Al contains simultaneously strong built-in fields in CuPc and C{sub 60} layers, with strengths of about 15 and -22 V/{mu}m, respectively. A high (on the order of 10{sup -3} C/m{sup 2}) positive space charge arises at the donor-acceptor interface, and the oppositely directed fields may either increase or reduce the efficiency of light-energy converters, depending on the heterostructure parameters.

  17. Magnetophotocurrent in Organic Bulk Heterojunction Photovoltaic Cells at Low Temperatures and High Magnetic Fields

    NASA Astrophysics Data System (ADS)

    Khachatryan, B.; Devir-Wolfman, A. H.; Tzabari, L.; Tessler, N.; Vardeny, Z. V.; Ehrenfreund, E.

    2016-04-01

    We study high-field (up to B ˜8.5 T ) magnetophotocurrent (MPC) related to photogenerated polaron pairs (PPs) in the temperature range T =10 - 320 K in organic bulk heterojunction photovoltaic cells. We find that in the high-field regime (B >1 T ), MPC (B ) response increases with B for temperature T >200 K but decreases with B at T <200 K . MPC (B ) response does not saturate even at the highest field studied, at all T . We attribute the observed high-field MPC (B ) response to two competing mechanisms within the PP spin states: (a) a spin-mixing mechanism caused by the difference in the donor-acceptor (or positive-negative polarons) g factors (the so-called "Δ g mechanism"), and (b) the spin polarization induced by thermal population of the PP Zeeman split levels. The nonsaturating MPC (B ) response at high fields and high temperatures indicates that there exist charge-transfer excitons (CTEs) with decay time in the subnanosecond time domain. With decreasing temperature, the CTE decay time sharply increases, thereby promoting an increase of the thermal spin-polarization contribution to the MPC (B ) response.

  18. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards

    SciTech Connect

    Brooks, William; Basso, Thomas; Coddington, Michael

    2015-10-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  19. Exploring Near-Field Radiative Heat Transfer for Thermo-photovoltaic Applications

    NASA Astrophysics Data System (ADS)

    Ganjeh, Yashar; Song, Bai; Sadat, Seid; Thompson, Dakotah; Fiorino, Anthony; Reddy, Pramod; Meyhofer, Edgar

    2014-03-01

    Understanding near-field radiative heat transfer (NFRHT) is critical for developing efficient thermo-photovoltaic devices. Theoretical predictions suggest that when the spatial separation of two parallel planes at different temperatures is less than their Wien's thermal wavelength, thermal transport via radiation can be greatly enhanced. The radiative heat flow across nanoscale gaps is predicted to be orders-of-magnitude higher than that given by Stefan-Boltzmann law, due to contribution of evanescent waves. In order to test these predictions, a novel experimental platform was designed and built enabling parallelization of two planar surfaces (50 μm by 50 μm) with 500 microradian resolution in their relative orientation. This platform was used to probe NFRHT between two planes and also between a plane and a sphere. It was found that, when a 50 μm diameter silica sphere was approximately 20 nm away from a 50 by 50 μm2 silica plane, a significant increase in radiative heat transfer coefficient was observed. This increase is 3 orders of magnitude higher than the value predicted by the blackbody limit. Other setups, including Au spheres and planes, and the plane-plane geometries are currently being investigated. 1) Army Research office (W911NF-12-1-0612), 2) NSF Thermal Transport Prcesses (CBET 1235691), 3) Center for Solar and Thermal Energy conversion, funded by the US Department of Energy, Office of Science, Basic Energy Sciences under award no. DE-SC0000957.

  20. Optical, electrical, and magnetic field studies of organic materials for light emitting diodes and photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Basel, Tek Prasad

    We studied optical, electrical, and magnetic field responses of films and devices based on organic semiconductors that are used for organic light emitting diodes (OLEDs) and photovoltaic (OPV) solar cell applications. Our studies show that the hyperfine interaction (HFI)-mediated spin mixing is the key process underlying various magnetic field effects (MFE) and spin transport in aluminum tris(8-hydroxyquinoline)[Alq3]-based OLEDs and organic spin-valve (OSV). Conductivity-detected magnetic resonance in OLEDs and magneto-resistance (MR) in OSVs show substantial isotope dependence. In contrast, isotope-insensitive behavior in the magneto-conductance (MC) of same devices is explained by the collision of spin ½ carriers with triplet polaron pairs. We used steady state optical spectroscopy for studying the energy transfer dynamics in films and OLEDs based on host-guest blends of the fluorescent polymer and phosphorescent molecule. We have also studied the magnetic-field controlled color manipulation in these devices, which provide a strong proof for the `polaron-pair' mechanism underlying the MFE in organic devices. The critical issue that hampers organic spintronics device applications is significant magneto-electroluminescence (MEL) at room temperature (RT). Whereas inorganic spin valves (ISVs) show RT magneto-resistance, MR>80%, however, the devices do not exhibit electroluminescence (EL). In contrast, OLEDs show substantive EL emission, and are particularly attractive because of their flexibility, low cost, and potential for multicolor display. We report a conceptual novel hybrid organic/inorganic spintronics device (h-OLED), where we employ both ISV with large MR at RT, and OLED that has efficient EL emission. We investigated the charge transfer process in an OPV solar cell through optical, electrical, and magnetic field measurements of thin films and devices based on a low bandgap polymer, PTB7 (fluorinated poly-thienothiophene-benzodithiophene). We found that

  1. Photovoltaics - The endless spring

    NASA Technical Reports Server (NTRS)

    Brandhorst, H. W., Jr.

    1984-01-01

    An overview of the developments in the photovoltaic field over the past decade or two is presened. Accomplishments in the terrestrial field are reviewed along with projections and challenges toward meeting cost goals. The contrasts and commonality of space and terrestrial photovoltaics are presented. Finally, a strategic philosophy of photovoltaics research highlighting critical factors, appropriate directions, emerging opportunities, and challenges of the future is given.

  2. Photovoltaics: The endless spring

    NASA Technical Reports Server (NTRS)

    Brandhorst, H. W., Jr.

    1984-01-01

    An overview of the developments in the photovoltaic field over the past decade or two is presented. Accomplishments in the terrestrial field are reviewed along with projections and challenges toward meeting cost goals. The contrasts and commonality of space and terrestrial photovoltaics are presented. Finally, a strategic philosophy of photovoltaics research highlighting critical factors, appropriate directions, emerging opportunities, and challenges of the future is given.

  3. Domestic Violence during Pregnancy in an Eastern City of Turkey: A Field Study

    ERIC Educational Resources Information Center

    Arslantas, Hulya; Adana, Filiz; Ergin, Filiz; Gey, Neriman; Bicer, Nejla; Kiransal, Nilufer

    2012-01-01

    Violence is an increasing and important community health problem that can be seen in any area of human life. Limited studies were found about domestic violence among pregnant women and its relation with social status of women. The aim of this study was to determine the prevalence and types of domestic violence during pregnancy, factors affecting…

  4. Design of a Glenn Research Center Solar Field Grid-Tied Photovoltaic Power System

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2009-01-01

    The NASA Glenn Research Center (GRC) designed, developed, and installed, a 37.5 kW DC photovoltaic (PV) Solar Field in the GRC West Area in the 1970s for the purpose of testing PV panels for various space and terrestrial applications. The PV panels are arranged to provide a nominal 120 VDC. The GRC Solar Field has been extremely successful in meeting its mission. The PV panels and the supporting electrical systems are all near their end of life. GRC has designed a 72 kW DC grid-tied PV power system to replace the existing GRC West Area Solar Field. The 72 kW DC grid-tied PV power system will provide DC solar power for GRC PV testing applications, and provide AC facility power for all times that research power is not required. A grid-tied system is connected directly to the utility distribution grid. Facility power can be obtained from the utility system as normal. The PV system is synchronized with the utility system to provide power for the facility, and excess power is provided to the utility for use by all. The project transfers space technology to terrestrial use via nontraditional partners. GRC personnel glean valuable experience with PV power systems that are directly applicable to various space power systems, and provide valuable space program test data. PV power systems help to reduce harmful emissions and reduce the Nation s dependence on fossil fuels. Power generated by the PV system reduces the GRC utility demand, and the surplus power aids the community. Present global energy concerns reinforce the need for the development of alternative energy systems. Modern PV panels are readily available, reliable, efficient, and economical with a life expectancy of at least 25 years. Modern electronics has been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy of at least 25 years. The report concludes that the GRC West Area grid-tied PV power system design is viable for a reliable

  5. Optically Induced PN Junction Diode and Photovoltaic Response on Ambipolar MoSe2 Field-effect Transistor

    NASA Astrophysics Data System (ADS)

    Pradhan, Nihar; Lu, Zhengguang; Rhodes, Daniel; Terrones, Mauricio; Smirnov, Dmitry; Balicas, Luis

    2015-03-01

    Transition metal dichalcogenides (TMDs) have emerged as an attractive material for electronic and optoelectronic devices due to their sizable band gap, flexibility and reduced dimensionality, which makes them promising candidates for applications in translucent optoelectronics components, such as solar cells and light emitting diodes. Here, we present an optically induced diode like response and concomitant photovoltaic effect in few-atomic layers molybdenum diselenide (MoSe2) field-effect transistors. Compared to recently reported PN junctions based on TMDs, ambipolar MoSe2 shows nearly ideal diode rectification under illumination, with a sizable photovoltaic efficiency. The observed light induced diode response under fixed gate voltage, yields a maximum open circuit voltage 0.28V and short circuit current 230nA at 30uW incident laser power. The sense of current rectification can be altered by changing the polarity of the applied gate voltage (Vbg) . At Vbg = 0V the highest electrical power obtained is 175pW corresponding to a maximum photovoltaic efficiency of 0.01%. These values increased to 11nW and 0.05% under a Vbg = -7.5V. At an excitation voltage 1V we observed maximum photocurrent responsivity surpassing 100mA/W with corresponding external quantum efficiency ~ 30%.

  6. Photovoltaics (Fact Sheet)

    SciTech Connect

    Not Available

    2012-11-01

    The U.S. Department of Energy (DOE) works with industry, academia, national laboratories, and other government agencies to advance solar photovoltaics (PV) domestically. The SunShot Initiative aims to achieve widespread, unsubsidized cost-competitiveness through an applied research and development (R&D) portfolio spanning PV materials, devices, and manufacturing technologies.

  7. Photovoltaics (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    DOE works with national labs, academia, and industry to support the domestic photovoltaics (PV) industry and research enterprise. SunShot aims to achieve widespread, unsubsidized cost-competitiveness through an applied research and development (R&D) portfolio spanning PV materials, devices, and manufacturing technologies.

  8. Photovoltaics (Fact Sheet)

    SciTech Connect

    DOE Solar Energy Technologies Program

    2011-10-13

    DOE works with national labs, academia, and industry to support the domestic photovoltaics (PV) industry and research enterprise. SunShot aims to achieve widespread, unsubsidized cost-competitiveness through an applied research and development (R&D) portfolio spanning PV materials, devices, and manufacturing technologies.

  9. Characterization of Photovoltaic Generators

    ERIC Educational Resources Information Center

    Boitier, V.; Cressault, Y.

    2011-01-01

    This paper discusses photovoltaic panel systems and reviews their electrical properties and use in several industrial fields. We explain how different photovoltaic panels may be characterized by undergraduate students at university using simple methods to retrieve their electrical properties (power, current and voltage) and compare these values…

  10. Potential for Photovoltaic Solar Installation in Non-Irrigated Corners of Center Pivot Irrigation Fields in the State of Colorado

    SciTech Connect

    Roberts, B.

    2011-07-01

    The State of Colorado expressed an interest in assessing the potential for photovoltaic (PV) solar installations on non-irrigated corners of center-pivot irrigation (CPI) fields throughout the state. Using aerial imagery and irrigated land data available from the Colorado Water Conservation Board, an assessment of potentially suitable sites was produced. Productivity estimates were calculated from that assessment. The total area of non-irrigated corners of CPI fields in Colorado was estimated to be 314,674 acres, which could yield 223,418 acres of installed PV panels assuming 71% coverage in triangular plots. The total potential annual electricity production for the state was estimated to be 56,821 gigawatt hours (GWH), with an average of 1.3 GWH per available plot.

  11. The worldwide market for photovoltaics in the rural sector

    NASA Technical Reports Server (NTRS)

    Brainard, W. A.

    1982-01-01

    The worldwide market for stand-alone photovoltaic power systems in three specific segments of the rural sector were determined. The worldwide market for photovoltaic power systems for village power, cottage industry, and agricultural applications were addressed. The objectives of these studies were to: The market potential for small stand-alone photovoltaic power system in specific application areas was assessed. Technical, social and institutional barriers to PV utilization were identified. Funding sources available to potential users was also identified and marketing strategies appropriate for each sector were recommended to PV product manufacturers. The studies were prepared on the basis of data gathered from domestic sources and from field trips to representative countries. Both country-specific and sector-specific results are discussed, and broadly applicable barriers pertinent to international marketing of PV products are presented.

  12. Wind loads on flat plate photovoltaic array fields. Phase III, final report

    SciTech Connect

    Miller, R.D.; Zimmerman, D.K.

    1981-04-01

    The results of an experimental analysis (boundary layer wind tunnel test) of the aerodynamic forces resulting from winds acting on flat plate photovoltaic arrays are presented. Local pressure coefficient distributions and normal force coefficients on the arrays are shown and compared to theoretical results. Parameters that were varied when determining the aerodynamic forces included tilt angle, array separation, ground clearance, protective wind barriers, and the effect of the wind velocity profile. Recommended design wind forces and pressures are presented, which envelop the test results for winds perpendicular to the array's longitudinal axis. This wind direction produces the maximum wind loads on the arrays except at the array edge where oblique winds produce larger edge pressure loads.

  13. Status of DOE and AID stand-alone photovoltaic system field tests

    NASA Technical Reports Server (NTRS)

    Bifano, W. J.; Delombard, R.; Ratajczak, A. F.; Scudder, L. R.

    1984-01-01

    The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system projects sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, and PV-powered vaccine refrigerator systems in six countries. The AID project includes a large village power system, a farmhouse system and two water pumping-irrigation systems in Tunisia, a water pumping/grain grinding system in Upper Volta, five medical clinic systems in four countries, PV-powered vaccine refrigerator systems in 18 countries and a PV-powered remote earth station in Indonesia. This paper reviews these PV projects and summarizes significant findings to date.

  14. Status of DOE and AID stand-alone photovoltaic system field tests

    SciTech Connect

    Bifano, W.J.; DeLombard, R.; Ratajczak, A.F.; Scudder, L.R.

    1984-05-01

    The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system projects sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, and PV-powered vaccine refrigerator systems in six countries. The AID project includes a large village power system, a farmhouse system and two water pumping-irrigation systems in Tunisia, a water pumping/grain grinding system in Upper Volta, five medical clinic systems in four countries, PV-powered vaccine refrigerator systems in 18 countries and a PVpowered remote earth station in Indonesia. This paper reviews these PV projects and summarizes significant findings to date.

  15. Status of DOE and AID stand-alone photovoltaic system field tests

    NASA Astrophysics Data System (ADS)

    Bifano, W. J.; Delombard, R.; Ratajczak, A. F.; Scudder, L. R.

    The NASA Lewis Research Center (LeRC) is managing stand-alone photovoltaic (PV) system projects sponsored by the U.S. Department of Energy (DOE) and the U.S. Agency for International Development (AID). The DOE project includes village PV power demonstration projects in Gabon (four sites) and the Marshall Islands, and PV-powered vaccine refrigerator systems in six countries. The AID project includes a large village power system, a farmhouse system and two water pumping-irrigation systems in Tunisia, a water pumping/grain grinding system in Upper Volta, five medical clinic systems in four countries, PV-powered vaccine refrigerator systems in 18 countries and a PV-powered remote earth station in Indonesia. This paper reviews these PV projects and summarizes significant findings to date.

  16. Field test analysis of concentrator photovoltaic system focusing on average photon energy and temperature

    NASA Astrophysics Data System (ADS)

    Husna, Husyira Al; Ota, Yasuyuki; Minemoto, Takashi; Nishioka, Kensuke

    2015-08-01

    The concentrator photovoltaic (CPV) system is unique and different from the common flat-plate PV system. It uses a multi-junction solar cell and a Fresnel lens to concentrate direct solar radiation onto the cell while tracking the sun throughout the day. The cell efficiency could reach over 40% under high concentration ratio. In this study, we analyzed a one year set of environmental condition data of the University of Miyazaki, Japan, where the CPV system was installed. Performance ratio (PR) was discussed to describe the system’s performance. Meanwhile, the average photon energy (APE) was used to describe the spectrum distribution at the site where the CPV system was installed. A circuit simulator network was used to simulate the CPV system electrical characteristics under various environmental conditions. As for the result, we found that the PR of the CPV systems depends on the APE level rather than the cell temperature.

  17. Field Guide for Testing Existing Photovoltaic Systems for Ground Faults and Installing Equipment to Mitigate Fire Hazards: November 2012 - October 2013

    SciTech Connect

    Brooks, William

    2015-02-01

    Ground faults and arc faults are the two most common reasons for fires in photovoltaic (PV) arrays and methods exist that can mitigate the hazards. This report provides field procedures for testing PV arrays for ground faults, and for implementing high resolution ground fault and arc fault detectors in existing and new PV system designs.

  18. Nanostructured photovoltaics

    NASA Astrophysics Data System (ADS)

    Fu, Lan; Tan, H. Hoe; Jagadish, Chennupati

    2013-01-01

    Energy and the environment are two of the most important global issues that we currently face. The development of clean and sustainable energy resources is essential to reduce greenhouse gas emission and meet our ever-increasing demand for energy. Over the last decade photovoltaics, as one of the leading technologies to meet these challenges, has seen a continuous increase in research, development and investment. Meanwhile, nanotechnology, which is considered to be the technology of the future, is gradually revolutionizing our everyday life through adaptation and incorporation into many traditional technologies, particularly energy-related technologies, such as photovoltaics. While the record for the highest efficiency is firmly held by multijunction III-V solar cells, there has never been a shortage of new research effort put into improving the efficiencies of all types of solar cells and making them more cost effective. In particular, there have been extensive and exciting developments in employing nanostructures; features with different low dimensionalities, such as quantum wells, nanowires, nanotubes, nanoparticles and quantum dots, have been incorporated into existing photovoltaic technologies to enhance their performance and/or reduce their cost. Investigations into light trapping using plasmonic nanostructures to effectively increase light absorption in various solar cells are also being rigorously pursued. In addition, nanotechnology provides researchers with great opportunities to explore the new ideas and physics offered by nanostructures to implement advanced solar cell concepts such as hot carrier, multi-exciton and intermediate band solar cells. This special issue of Journal of Physics D: Applied Physics contains selected papers on nanostructured photovoltaics written by researchers in their respective fields of expertise. These papers capture the current excitement, as well as addressing some open questions in the field, covering topics including the

  19. Organic photovoltaics

    NASA Astrophysics Data System (ADS)

    Leo, Karl

    2016-08-01

    Organic photovoltaics are on the verge of revolutionizing building-integrated photovoltaics. For other applications, however, several basic open scientific questions need answering to, in particular, further improve energy-conversion efficiency and lifetime.

  20. Degradation of Photovoltaic Modules Under High Voltage Stress in the Field: Preprint

    SciTech Connect

    del Cueto, J. A.; Rummel, S. R.

    2010-08-01

    The degradation in performance for eight photovoltaic (PV) modules stressed at high voltage (HV) is presented. Four types of modules--tandem-junction and triple-junction amorphous thin-film silicon, plus crystalline and polycrystalline silicon modules--were tested, with a pair of each biased at opposite polarities. They were deployed outdoors between 2001 and 2009 with their respective HV leakage currents through the module encapsulation continuously monitored with a data acquisition system, along with air temperature and relative humidity. For the first 5 years, all modules were biased continuously at fixed 600 VDC, day and night. In the last 2 years, the modules were step-bias stressed cyclically up and down in voltage between 10 and 600 VDC, in steps of tens to hundreds of volts. This allowed characterization of leakage current versus voltage under a large range of temperature and moisture conditions, facilitating determination of leakage paths. An analysis of the degradation is presented, along with integrated leakage charge. In HV operation: the bulk silicon modules degraded either insignificantly or at rates of 0.1%/yr higher than modules not biased at HV; for the thin-film silicon modules, the added loss rates are insignificant for one type, or 0.2%/yr-0.6%/yr larger for the other type.

  1. Modular array field designs for tracking flat-plate photovoltaic systems, volume 1

    NASA Astrophysics Data System (ADS)

    Castle, J. A.

    1987-06-01

    This report addresses the optimization of utility-sized, tracking flat-plate photovoltaic power systems. Structures optimized were one single-axis and one dual-axis tracking system using currently available system designs as baseline engineering reference points. Passive thermal-hydraulic tracking drive systems were evaluated and Freon-hydraulic units were found to be cost-effective in single-axis tracking. Building block configurations ranging in size from 35 kW to 5 MW were established using the optimized single- and dual-axis tracking structures, and their reliability and availability were analyzed. A 1-MW single-axis building block design was selected to develop engineering plans for a 100-MW PV power plant designed to operate unattended. Eleven-percent efficient PV panels at $220/sq m were used in the study, and single-axis, flat-plate tracking systems were found to be significantly more cost-effective than dual-axis systems. A prototype tracking array was built and tested at Sandia, where cost and performance data supported lower economic projections for large PV tracking arrays.

  2. Photovoltaic device

    DOEpatents

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-06-02

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device with a multilayered photovoltaic cell assembly and a body portion joined at an interface region and including an intermediate layer, at least one interconnecting structural member, relieving feature, unique component geometry, or any combination thereof.

  3. Photovoltaic device

    SciTech Connect

    Reese, Jason A.; Keenihan, James R.; Gaston, Ryan S.; Kauffmann, Keith L.; Langmaid, Joseph A.; Lopez, Leonardo C.; Maak, Kevin D.; Mills, Michael E.; Ramesh, Narayan; Teli, Samar R.

    2015-09-01

    The present invention is premised upon an improved photovoltaic device ("PV device"), more particularly to an improved photovoltaic device (10) with a multilayered photovoltaic cell assembly (100) and a body portion (200) joined at an interface region (410) and including an intermediate layer (500), at least one interconnecting structural member (1500), relieving feature (2500), unique component geometry, or any combination thereof.

  4. A strain or electric field induced direct bandgap in ultrathin silicon film and its application in photovoltaics or photocatalysis.

    PubMed

    Cao, Tengfei; Wang, Da; Geng, Dong-Sheng; Liu, Li-Min; Zhao, Jijun

    2016-03-01

    The indirect bandgap character of silicon greatly limits its applications in electronic or optoelectronic devices, and direct bandgaps are highly desirable in all silicon allotropes. The successful synthesis of ultrathin or even monolayer silicon films experimentally has opened new opportunities to further modulate the electronic structure of silicon through external modulation. In this work, strain or electric field effects on the electronic structure of ultrathin silicon film (USF) are systematically explored. The results demonstrate that all USFs are indirect band-gap semiconductors; interestingly, tensile strain or electric field efficiently tunes the USFs into direct band gap semiconductors. The indirect to direct band gap transition in the USFs not only extends their light adsorption spectra into the visible light region but also greatly enhances the adsorption intensity. Because of this, strained USFs have great potential to be used as a high-performance photovoltaic material. Furthermore, the high stability, moderate band-gap and proper band edge positions demonstrate that monolayer and bilayer USFs can also be used as photocatalysts for water splitting. PMID:26888664

  5. Characterization of photovoltaic generators

    NASA Astrophysics Data System (ADS)

    Boitier, V.; Cressault, Y.

    2011-05-01

    This paper discusses photovoltaic panel systems and reviews their electrical properties and use in several industrial fields. We explain how different photovoltaic panels may be characterized by undergraduate students at university using simple methods to retrieve their electrical properties (power, current and voltage) and compare these values with those stated by the manufacturer. We also discuss how the efficiency of solar panels depends upon their construction, temperature, net irradiation and geographic location.

  6. Tuning the photovoltaic effect of multiferroic CoFe2O4/Pb(Zr, Ti)O3 composite films by magnetic fields

    NASA Astrophysics Data System (ADS)

    Pan, Dan-Feng; Chen, Guang-Yi; Bi, Gui-Feng; Zhang, Hao; Liu, Jun-Ming; Wang, Guang-Hou; Wan, Jian-Guo

    2016-05-01

    The 0-3 type CoFe2O4-Pb(Zr,Ti)O3 (CFO-PZT) multiferroic composite films have been prepared by a sol-gel process and spin-coating technique. A confirmable photovoltaic effect is observed under ultraviolet light irradiation. Moreover, this photovoltaic effect can be tuned by external magnetic fields. The maximum magnetic modulation ratios of short-circuit current density and open-circuit voltage can reach as high as 13.7% and 12.8% upon the application of 6 kOe DC magnetic field. Through remnant polarization measurements under various magnetic fields and detailed analysis of the energy band structures, we elucidate the mechanism of tuning photovoltaic effect by magnetic fields and attribute it to the combination of two factors. One is the decreased ferroelectric-polarization-induced depolarization electric field and another is the band structure reconstruction at CFO-PZT interfaces, both of which are dominated by the magnetoelectric coupling via interfacial stress transferring at nanoscale. This work makes some attempts of coupling photo-induced effects with magnetoelectric effect in multiferroic materials and will widen the practical ranges of multiferroic-based applications.

  7. Survey of Facilities for Testing Photovoltaics

    NASA Technical Reports Server (NTRS)

    Weaver, R. W.

    1982-01-01

    42-page report describes facilities capable of testing complete photovoltaic systems, subsystems, or components. Compilation includes facilities and capabilities of five field centers of national photovoltaics program, two state-operated agencies, and five private testing laboratories.

  8. Domestic Violence

    MedlinePlus

    ... AQ FREQUENTLY ASKED QUESTIONS FAQ083 WOMEN’S HEALTH Domestic Violence • What is domestic violence? • What are the types of abuse? • How can ... available to help abused women? What is domestic violence? Domestic violence is a pattern of threatening or ...

  9. International photovoltaic program. Volume 2: Appendices

    NASA Technical Reports Server (NTRS)

    Costello, D.; Koontz, R.; Posner, D.; Heiferling, P.; Carpenter, P.; Forman, S.; Perelman, L.

    1979-01-01

    The results of analyses conducted in preparation of an international photovoltaic marketing plan are summarized. Included are compilations of relevant statutes and existing Federal programs; strategies designed to expand the use of photovoltaics abroad; information on the domestic photovoltaic plan and its impact on the proposed international plan; perspectives on foreign competition; industry views on the international photovoltaic market and ideas about the how US government actions could affect this market;international financing issues; and information on issues affecting foreign policy and developing countries.

  10. Development of a standard modular design for low-cost flat-panel photovoltaic array fields

    SciTech Connect

    Carmichael, D.C.; Alexander, G.; Noel, G.T.; Smith, R.W.; Huss, W.R.

    1982-11-01

    Array-field balance-of-system (BOS) and engineering costs must be reduced for PV power systems to be cost effective for grid-connected applications. Therefore, a study was conducted to develop an innovative and integrated structural and electrical array-field design optimized for minimum life-cycle energy cost, to identify a modular Building Block from this design to be used to construct various sizes of PV array fields at minimum cost, and to standardize the design and prepare complete construction specifications and engineering drawings for reduction of costs of site-specific engineering design and installation. The subsystem area investigated include the support structure, foundation, site preparation, PV module wiring, grounding, ligntning protection, and electromagnetic-interference (EMI) suppression. Maximum use of information from other PV system designs and installation methods were incorporated. Over 50 designs were prepared and evaluated for cost and the final array field selected, developed, and incorporated into a standard Building Block design. Results indicated that the new design greatly reduced BOS costs compared to those of previous installations, provided a high degree of reliability and minimum maintenance, required no major capital investment or long-lead time for an automated plant or equipment, and could be used immediately. The low cost of the array field BOS was determined to be realistic and economically viable.

  11. Field-enhanced recombination at low temperatures in an organic photovoltaic blend

    NASA Astrophysics Data System (ADS)

    Athanasopoulos, S.; Greenham, N. C.; Friend, R. H.; Chepelianskii, A. D.

    2015-09-01

    We report on the nontrivial field dependence of charge-carrier recombination in an organic blend at low temperatures. A new microwave resonance technique for monitoring charge recombination in organic semiconductors at low temperatures is applied in bulk heterojunction poly(3-hexylthiophene):[6,6]-phenyl-C61-butyric acid methyl ester blends with results showing that an external electric field can in fact increase recombination. Monte Carlo simulations suggest that this contradiction to conventional wisdom relates to electron-hole pairs that are separated at donor-acceptor interfaces where the electric field acts in synergy with their Coulomb attraction. For this behavior to occur a critical initial separation of ˜5 nm between the carriers is required.

  12. Domestic Violence

    MedlinePlus

    Domestic violence is a type of abuse. It usually involves a spouse or partner, but it can also ... a child, elderly relative, or other family member. Domestic violence may include Physical violence that can lead to ...

  13. Domestic violence

    MedlinePlus

    Domestic violence is when a person uses abusive behavior to control a partner or other family member. The ... of any age, sex, culture, or class. When domestic violence is aimed at a child, it is called ...

  14. Domestic Violence

    MedlinePlus

    Domestic violence is a type of abuse. It usually involves a spouse or partner, but it can also be ... child, elderly relative, or other family member. Domestic violence may include Physical violence that can lead to ...

  15. Photovoltaic cell

    DOEpatents

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  16. A draft genome of field pennycress (Thlaspi arvense) provides tools for the domestication of a new winter biofuel crop.

    PubMed

    Dorn, Kevin M; Fankhauser, Johnathon D; Wyse, Donald L; Marks, M David

    2015-04-01

    Field pennycress (Thlaspi arvense L.) is being domesticated as a new winter cover crop and biofuel species for the Midwestern United States that can be double-cropped between corn and soybeans. A genome sequence will enable the use of new technologies to make improvements in pennycress. To generate a draft genome, a hybrid sequencing approach was used to generate 47 Gb of DNA sequencing reads from both the Illumina and PacBio platforms. These reads were used to assemble 6,768 genomic scaffolds. The draft genome was annotated using the MAKER pipeline, which identified 27,390 predicted protein-coding genes, with almost all of these predicted peptides having significant sequence similarity to Arabidopsis proteins. A comprehensive analysis of pennycress gene homologues involved in glucosinolate biosynthesis, metabolism, and transport pathways revealed high sequence conservation compared with other Brassicaceae species, and helps validate the assembly of the pennycress gene space in this draft genome. Additional comparative genomic analyses indicate that the knowledge gained from years of basic Brassicaceae research will serve as a powerful tool for identifying gene targets whose manipulation can be predicted to result in improvements for pennycress. PMID:25632110

  17. A draft genome of field pennycress (Thlaspi arvense) provides tools for the domestication of a new winter biofuel crop

    PubMed Central

    Dorn, Kevin M.; Fankhauser, Johnathon D.; Wyse, Donald L.; Marks, M. David

    2015-01-01

    Field pennycress (Thlaspi arvense L.) is being domesticated as a new winter cover crop and biofuel species for the Midwestern United States that can be double-cropped between corn and soybeans. A genome sequence will enable the use of new technologies to make improvements in pennycress. To generate a draft genome, a hybrid sequencing approach was used to generate 47 Gb of DNA sequencing reads from both the Illumina and PacBio platforms. These reads were used to assemble 6,768 genomic scaffolds. The draft genome was annotated using the MAKER pipeline, which identified 27,390 predicted protein-coding genes, with almost all of these predicted peptides having significant sequence similarity to Arabidopsis proteins. A comprehensive analysis of pennycress gene homologues involved in glucosinolate biosynthesis, metabolism, and transport pathways revealed high sequence conservation compared with other Brassicaceae species, and helps validate the assembly of the pennycress gene space in this draft genome. Additional comparative genomic analyses indicate that the knowledge gained from years of basic Brassicaceae research will serve as a powerful tool for identifying gene targets whose manipulation can be predicted to result in improvements for pennycress. PMID:25632110

  18. Photovoltaic product directory and buyers guide

    SciTech Connect

    Watts, R.L.; Smith, S.A.; Mazzucchi, R.P.

    1981-06-01

    Basic information on photovoltaic conversion technology is provided for those unfamiliar with the field. Various types of photovoltaic products and systems currently available off-the-shelf are described. These include products without batteries, battery chargers, power packages, home electric systems, and partial systems. Procedures are given for designing a photovoltaic system from scratch. A few custom photovoltaic systems are described, and a list is compiled of photovoltaic firms which can provide custom systems. Guidance is offered for deciding whether or not to use photovoltaic products. A variety of installations are described and their performance is appraised by the owners. Information is given on various financial incentives available from state and federal governments. Sources of additional information on photovoltaics are listed. A matrix is provided indicating the sources of various types of photovoltaic products. The addresses of suppliers are listed. (LEW)

  19. Photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Groth, H.

    1982-11-01

    The utilization of photovoltaic generators in measuring and signalling installations, communication systems, water pumping, and electric power plants is discussed. The advantages of solar generators over conventional power supply equipment are outlined.

  20. Photovoltaic module reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986 to 1990. The reliability photovoltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warrantees available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the U.S., PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  1. Photovoltaic array performance model.

    SciTech Connect

    Kratochvil, Jay A.; Boyson, William Earl; King, David L.

    2004-08-01

    This document summarizes the equations and applications associated with the photovoltaic array performance model developed at Sandia National Laboratories over the last twelve years. Electrical, thermal, and optical characteristics for photovoltaic modules are included in the model, and the model is designed to use hourly solar resource and meteorological data. The versatility and accuracy of the model has been validated for flat-plate modules (all technologies) and for concentrator modules, as well as for large arrays of modules. Applications include system design and sizing, 'translation' of field performance measurements to standard reporting conditions, system performance optimization, and real-time comparison of measured versus expected system performance.

  2. Vacuum lamination of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Burger, D. R.

    1982-01-01

    Vacuum lamination of terrestrial photovoltaic modules is a new high volume process requiring new equipment and newly develop materials. Equipment development, materials research, and some research in related fields and testing methods are discussed.

  3. Photovoltaic Engineering

    NASA Technical Reports Server (NTRS)

    2005-01-01

    The Ohio Aerospace Institute through David Scheiman and Phillip Jenkins provided the Photovoltaics Branch at the NASA Glenn Research Center (GRC) with expertise in photovoltaic (PV) research, flight experiments and solar cell calibration. NASA GRC maintains the only world-class solar cell calibration and measurement facility within NASA. GRC also has a leadership role within the solar cell calibration community, and is leading the effort to develop ISO standards for solar cell calibration. OAI scientists working under this grant provided much of the expertise and leadership in this area.

  4. Environmental aging in polycrystalline-Si photovoltaic modules: comparison of chamber-based accelerated degradation studies with field-test data

    NASA Astrophysics Data System (ADS)

    Lai, T.; Biggie, R.; Brooks, A.; Potter, B. G.; Simmons-Potter, K.

    2015-09-01

    Lifecycle degradation testing of photovoltaic (PV) modules in accelerated-degradation chambers can enable the prediction both of PV performance lifetimes and of return-on-investment for installations of PV systems. With degradation results strongly dependent on chamber test parameters, the validity of such studies relative to fielded, installed PV systems must be determined. In the present work, accelerated aging of a 250 W polycrystalline silicon module is compared to real-time performance degradation in a similar polycrystalline-silicon, fielded, PV technology that has been operating since October 2013. Investigation of environmental aging effects are performed in a full-scale, industrial-standard environmental chamber equipped with single-sun irradiance capability providing illumination uniformity of 98% over a 2 x 1.6 m area. Time-dependent, photovoltaic performance (J-V) is evaluated over a recurring, compressed night-day cycle providing representative local daily solar insolation for the southwestern United States, followed by dark (night) cycling. This cycle is synchronized with thermal and humidity environmental variations that are designed to mimic, as closely as possible, test-yard conditions specific to a 12 month weather profile for a fielded system in Tucson, AZ. Results confirm the impact of environmental conditions on the module long-term performance. While the effects of temperature de-rating can be clearly seen in the data, removal of these effects enables the clear interpretation of module efficiency degradation with time and environmental exposure. With the temperature-dependent effect removed, the normalized efficiency is computed and compared to performance results from another panel of similar technology that has previously experienced identical climate changes in the test yard. Analysis of relative PV module efficiency degradation for the chamber-tested system shows good comparison to the field-tested system with ~2.5% degradation following

  5. Domestic Violence

    MedlinePlus

    ... to anyone regardless of race, age, sexual orientation, religion, or gender. Domestic violence affects people of all ... ABOUT The Attorney General Budget & Performance Strategic Plans History AGENCIES BUSINESS Business Opportunities Small & Disadvantaged Business Grants ...

  6. Photovoltaic cell

    SciTech Connect

    Bronstein-Bonte, I.Y.; Fischer, A.B.

    1986-12-16

    This patent describes a product comprising a photovoltaic cell including a luminescent dye which will absorb radiation at a wavelength to which the cell is not significantly responsive and emit radiation at a higher wavelength at which it is responsive. The improvement described here is wherein the dye comprises a lepidopterene.

  7. Photovoltaic energy

    NASA Astrophysics Data System (ADS)

    1990-01-01

    In 1989, the U.S. photovoltaic industry enjoyed a growth rate of 30 percent in sales for the second year in a row. This sends a message that the way we think about electricity is changing. Instead of big energy projects that perpetuate environmental and economic damage, there is a growing trend toward small renewable technologies that are well matched to end-user needs and operating conditions. As demand grows and markets expand, investment capital will be drawn to the industry and new growth trends will emerge. The photovoltaic industry around the world achieved record shipments also. Worldwide shipments of photovoltaic (PV) modules for 1989 totaled more than 40 megawatts (MW), nearly a 20 percent increase over last year's shipments. The previous two years showed increases in worldwide shipments of 23 and 25 percent, respectively. If this growth rate continues through the 1990s, as industry back orders would indicate, 300 to 1000 MW of PV-supplied power could be on line by 2000. Photovoltaic systems have low environmental impact and they are inexpensive to operate and maintain. Using solid-state technology, PV systems directly convert sunlight to electricity without high-temperature fluids or moving parts that could cause mechanical failure. This makes the technology very reliable.

  8. Photovoltaic module reliability workshop

    SciTech Connect

    Mrig, L.

    1990-01-01

    The paper and presentations compiled in this volume form the Proceedings of the fourth in a series of Workshops sponsored by Solar Energy Research Institute (SERI/DOE) under the general theme of photovoltaic module reliability during the period 1986--1990. The reliability Photo Voltaic (PV) modules/systems is exceedingly important along with the initial cost and efficiency of modules if the PV technology has to make a major impact in the power generation market, and for it to compete with the conventional electricity producing technologies. The reliability of photovoltaic modules has progressed significantly in the last few years as evidenced by warranties available on commercial modules of as long as 12 years. However, there is still need for substantial research and testing required to improve module field reliability to levels of 30 years or more. Several small groups of researchers are involved in this research, development, and monitoring activity around the world. In the US, PV manufacturers, DOE laboratories, electric utilities and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in this field were brought together under SERI/DOE sponsorship to exchange the technical knowledge and field experience as related to current information in this important field. The papers presented here reflect this effort.

  9. Photovoltaic fibers

    NASA Astrophysics Data System (ADS)

    Gaudiana, Russell; Eckert, Robert; Cardone, John; Ryan, James; Montello, Alan

    2006-08-01

    It was realized early in the history of Konarka that the ability to produce fibers that generate power from solar energy could be applied to a wide variety of applications where fabrics are utilized currently. These applications include personal items such as jackets, shirts and hats, to architectural uses such as awnings, tents, large covers for cars, trucks and even doomed stadiums, to indoor furnishings such as window blinds, shades and drapes. They may also be used as small fabric patches or fiber bundles for powering or recharging batteries in small sensors. Power generating fabrics for clothing is of particular interest to the military where they would be used in uniforms and body armor where portable power is vital to field operations. In strong sunlight these power generating fabrics could be used as a primary source of energy, or they can be used in either direct sunlight or low light conditions to recharge batteries. Early in 2002, Konarka performed a series of proof-of-concept experiments to demonstrate the feasibility of building a photovoltaic cell using dye-sensitized titania and electrolyte on a metal wire core. The approach taken was based on the sequential coating processes used in making fiber optics, namely, a fiber core, e.g., a metal wire serving as the primary electrode, is passed through a series of vertically aligned coating cups. Each of the cups contains a coating fluid that has a specific function in the photocell. A second wire, used as the counter electrode, is brought into the process prior to entering the final coating cup. The latter contains a photopolymerizable, transparent cladding which hardens when passed through a UV chamber. Upon exiting the UV chamber, the finished PV fiber is spooled. Two hundred of foot lengths of PV fiber have been made using this process. When the fiber is exposed to visible radiation, it generates electrical power. The best efficiency exhibited by these fibers is 6% with an average value in the 4

  10. Photovoltaic Materials

    SciTech Connect

    Duty, C.; Angelini, J.; Armstrong, B.; Bennett, C.; Evans, B.; Jellison, G. E.; Joshi, P.; List, F.; Paranthaman, P.; Parish, C.; Wereszczak, A.

    2012-10-15

    modules in the field for 25 years. Under this project, Ferro leveraged world leading analytical capabilities at ORNL to characterize the paste-to-silicon interface microstructure and develop high efficiency next generation contact pastes. Ampulse Corporation is developing a revolutionary crystalline-silicon (c-Si) thin-film solar photovoltaic (PV) technology. Utilizing uniquely-textured substrates and buffer materials from the Oak Ridge National Laboratory (ORNL), and breakthroughs in Hot-Wire Chemical Vapor Deposition (HW-CVD) techniques in epitaxial silicon developed at the National Renewable Energy Laboratory (NREL), Ampulse is creating a solar technology that is tunable in silicon thickness, and hence in efficiency and economics, to meet the specific requirements of multiple solar PV applications. This project focused on the development of a high rate deposition process to deposit Si, Ge, and Si1-xGex films as an alternate to hot-wire CVD. Mossey Creek Solar is a start-up company with great expertise in the solar field. The primary interest is to create and preserve jobs in the solar sector by developing high-yield, low-cost, high-efficiency solar cells using MSC-patented and -proprietary technologies. The specific goal of this project was to produce large grain formation in thin, net-shape-thickness mc-Si wafers processed with high-purity silicon powder and ORNL's plasma arc lamp melting without introducing impurities that compromise absorption coefficient and carrier lifetime. As part of this project, ORNL also added specific pieces of equipment to enhance our ability to provide unique insight for the solar industry. These capabilities include a moisture barrier measurement system, a combined physical vapor deposition and sputtering system dedicated to cadmium-containing deposits, adeep level transient spectroscopy system useful for identifying defects, an integrating sphere photoluminescence system, and a high-speed ink jet printing system. These tools were

  11. Photovoltaic Roofs

    NASA Technical Reports Server (NTRS)

    Drummond, R. W., Jr.; Shepard, N. F., Jr.

    1984-01-01

    Solar cells perform two functions: waterproofing roof and generating electricity. Sections through horizontal and slanting joints show overlapping modules sealed by L-section rubber strips and side-by-side modules sealed by P-section strips. Water seeping through seals of slanting joints drains along channels. Rooftop photovoltaic array used watertight south facing roof, replacing shingles, tar, and gravel. Concept reduces cost of residential solar-cell array.

  12. Domestic violence.

    PubMed

    2016-03-30

    Essential facts Domestic violence and abuse includes any incident or repeated incidents of controlling, coercive or threatening behaviour, violence or abuse between family members or intimate partners (including former partners). It can involve psychological, physical, sexual, financial and emotional abuse, as well as 'honour'-based violence and forced marriage. According to the Office for National Statistics, at least 1.4 million women and 700,000 men aged between 16 and 59 experienced domestic abuse in England and Wales in 2013/14 - equivalent to 8.5% of women and 4.5% of men. PMID:27027171

  13. A water-budget approach to estimating potential groundwater recharge from two domestic sewage disposal fields in eastern Bernalillo County, New Mexico, 2011-12

    USGS Publications Warehouse

    Crilley, Dianna M.; Collison, Jake W.

    2015-01-01

    During this study, the disposal fields at sites A and B received a measured volume of effluent from two-person domestic residences equipped with an onsite low-pressure dosing system. A combined evapotranspiration measurement and modeling technique was used to estimate the amount of evapotranspirative loss from the disposal field and from the surrounding terrain. A portable hemispherical flux chamber was used to measure evapotranspiration at fixed locations on the disposal fields and on the surrounding terrain at sites A and B. Data from hemispherical flux chamber measurements were used to calibrate a Penman-Monteith modeled evapotranspiration rate on the disposal field and on the surrounding terrain at site A from January 1, 2011, to December 31, 2011, and from January 1, 2012, to December 31, 2012, and at site B from January 1, 2011, to December 31, 2011. Micrometeorological and soil data from instrumentation on the disposal fields and on the surrounding terrain at sites A and B were used as input data into the Penman-Monteith equation. The mean potential recharge from disposal field effluent during 2011–12 at sites A and B was 63 percent of the volume of effluent dosed to the disposal field.

  14. Impact to Underground Sources of Drinking Water and Domestic Wells from Production Well Stimulation and Completion Practices in the Pavillion, Wyoming, Field.

    PubMed

    DiGiulio, Dominic C; Jackson, Robert B

    2016-04-19

    A comprehensive analysis of all publicly available data and reports was conducted to evaluate impact to Underground Sources of Drinking Water (USDWs) as a result of acid stimulation and hydraulic fracturing in the Pavillion, WY, Field. Although injection of stimulation fluids into USDWs in the Pavillion Field was documented by EPA, potential impact to USDWs at the depths of stimulation as a result of this activity was not previously evaluated. Concentrations of major ions in produced water samples outside expected levels in the Wind River Formation, leakoff of stimulation fluids into formation media, and likely loss of zonal isolation during stimulation at several production wells, indicates that impact to USDWs has occurred. Detection of organic compounds used for well stimulation in samples from two monitoring wells installed by EPA, plus anomalies in major ion concentrations in water from one of these monitoring wells, provide additional evidence of impact to USDWs and indicate upward solute migration to depths of current groundwater use. Detections of diesel range organics and other organic compounds in domestic wells <600 m from unlined pits used prior to the mid-1990s to dispose diesel-fuel based drilling mud and production fluids suggest impact to domestic wells as a result of legacy pit disposal practices. PMID:27022977

  15. Organic photovoltaics

    NASA Astrophysics Data System (ADS)

    Demming, Anna; Krebs, Frederik C.; Chen, Hongzheng

    2013-12-01

    Energy inflation, the constant encouragement to economize on energy consumption and the huge investments in developing alternative energy resources might seem to suggest that there is a global shortage of energy. Far from it, the energy the Sun beams on the Earth each hour is equivalent to a year's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating effectively across the electromagnetic spectrum remains a challenge. 'The trend is towards engineering low bandgap polymers with a wide optical absorption range and efficient hole/electron transport materials, so that light harvesting in the red and infrared region is enhanced and as much light of the solar spectrum as possible can be converted into an electrical current', explains Mukundan Thelakkat and colleagues in Germany, the US and UK. In this special issue they report on how charge carrier mobility and morphology of the active blend layer in thin film organic solar cells correlate with device parameters [2]. The work contributes to a better understanding of the solar-cell characteristics of polymer:fullerene blends, which form the material basis for some of the most

  16. Helium and methane anomalies in domestic well waters in southwestern Saskatchewan, Canada, and their relationship to other dissolved constituents, oil and gas fields, and tectonic patterns

    NASA Astrophysics Data System (ADS)

    Dyck, Willy; Dunn, Colin E.

    1986-11-01

    During the summer of 1976 a regional groundwater survey was undertaken in an area of 18,000 km2 in southwestern Saskatchewan. Approximately 940 domestic wells and springs were sampled at a density of 1 per 13 km2, where possible. The samples were analyzed for up to 30 variables, including He, CH4, and many trace and minor elements. The results of the survey are related to regional topographic, geological, and hydrological features. Of particular interest are CH4 and He anomalies associated with known gas and oil reservoirs in the region. Several anomalies of similar magnitude occur away from known reservoirs and hence may point to new ones. The close association of CH4 with He, sample depth and deeper "softer" waters, as indicated by the positive correlations of CH4 with He, Na, CO2-3, HCO-3 and sample depth is postulated to be a good criterion for distinguishing between reservoir CH4 and marsh gas. The coincidence of CH4 and He anomalies with known tectonic features also indicates fracture leakage from depth and the possible existence of oil and gas fields. Regional surveys of domestic well waters can be of use in delineating areas with proven and potential oil and gas reservoirs at depth.

  17. Classical swine fever virus: clinical, virological, serological and hematological findings after infection of domestic pigs and wild boars with the field isolate "Spante" originating from wild boar.

    PubMed

    Kaden, V; Ziegler, U; Lange, E; Dedek, J

    2000-01-01

    A classical swine fever virus (CSFV) field isolate originating from wild boar was investigated on its virulence in domestic pigs and wild boar. Three weaner pigs and two wild boars (yearlings) were intranasally inoculated with the isolate "Spante" and tested for clinical, virological, hematological and serological findings until day 31 after infection (p. i.). One day p. i. the piglets were put in contact to three sentinel pigs. During a period of 31 d neither the domestic pigs nor the wild boars showed clinical signs specific for CSF. Two infected weaner pigs became transiently viraemic, transmitted CSFV in nasal secretions, showed a slight leukopenia and reacted serologically positive. The contact infection resulted in a viraemia in two sentinel piglets on day 30. Only one contact animal developed antibodies. None of the wild boars became viraemic, excreted CSFV in nasal secretions or developed antibodies. The CSFV isolate "Spante" represents a low virulent virus. Referring to a significant higher percentage of virologically positive tissue samples after nested PCR compared with the virus isolation, persistence of CSFV is discussed. PMID:11153219

  18. Organic photovoltaics

    NASA Astrophysics Data System (ADS)

    Demming, Anna; Krebs, Frederik C.; Chen, Hongzheng

    2013-12-01

    Energy inflation, the constant encouragement to economize on energy consumption and the huge investments in developing alternative energy resources might seem to suggest that there is a global shortage of energy. Far from it, the energy the Sun beams on the Earth each hour is equivalent to a year's supply, even at our increasingly ravenous rate of global energy consumption [1]. But it's not what you have got it's what you do with it. Hence the intense focus on photovoltaic research to find more efficient ways to harness energy from the Sun. Recently much of this research has centred on organic solar cells since they offer simple, low-cost, light-weight and large-area flexible photovoltaic structures. This issue with guest editors Frederik C Krebs and Hongzheng Chen focuses on some of the developments at the frontier of organic photovoltaic technology. Improving the power conversion efficiency of organic photovoltaic systems, while maintaining the inherent material, economic and fabrication benefits, has absorbed a great deal of research attention in recent years. Here significant progress has been made with reports now of organic photovoltaic devices with efficiencies of around 10%. Yet operating effectively across the electromagnetic spectrum remains a challenge. 'The trend is towards engineering low bandgap polymers with a wide optical absorption range and efficient hole/electron transport materials, so that light harvesting in the red and infrared region is enhanced and as much light of the solar spectrum as possible can be converted into an electrical current', explains Mukundan Thelakkat and colleagues in Germany, the US and UK. In this special issue they report on how charge carrier mobility and morphology of the active blend layer in thin film organic solar cells correlate with device parameters [2]. The work contributes to a better understanding of the solar-cell characteristics of polymer:fullerene blends, which form the material basis for some of the most

  19. Experimental and field investigations on the role of birds as hosts of Leishmania infantum, with emphasis on the domestic chicken.

    PubMed

    Otranto, Domenico; Testini, Gabriella; Buonavoglia, Canio; Parisi, Antonio; Brandonisio, Olga; Circella, Elena; Dantas-Torres, Filipe; Camarda, Antonio

    2010-01-01

    In this study, 19 chickens were experimentally infected by Leishmania infantum and tissue samples, collected at different times, were cultured and subjected to conventional PCR and/or real time PCR (qPCR) to assess their susceptibility to infection. In addition, 121 serum samples from rural chickens (n=73) and backyard birds (n=48) were tested for anti-L. infantum antibodies by indirect immunofluorescence test. All the 19 animals showed to be molecularly positive at least at one tissue sample. In particular, 26 tissue samples from the experimentally infected chickens were positive on conventional PCR and/or qPCR but no clinical signs or seroconversion were detected and all tissue cultures were negative. Accordingly, all serum samples from rural chickens were negative whereas four (8.4%) from game birds (three Anser anser and one Phasianus colchicus) were positive. These results indicate that chickens are not suitable hosts for L. infantum under experimental condition. The occurrence of anti-L. infantum antibodies in domestic gooses (A. anser) and in a pheasant (P. colchicus) points out their possible role in the epidemiology of visceral leishmaniasis. PMID:19818726

  20. Photovoltaic solar concentrator

    SciTech Connect

    Nielson, Gregory N.; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J.; Sanchez, Carlos Anthony; Clews, Peggy J.; Gupta, Vipin P.

    2015-09-08

    A process including forming a photovoltaic solar cell on a substrate, the photovoltaic solar cell comprising an anchor positioned between the photovoltaic solar cell and the substrate to suspend the photovoltaic solar cell from the substrate. A surface of the photovoltaic solar cell opposite the substrate is attached to a receiving substrate. The receiving substrate may be bonded to the photovoltaic solar cell using an adhesive force or a metal connecting member. The photovoltaic solar cell is then detached from the substrate by lifting the receiving substrate having the photovoltaic solar cell attached thereto and severing the anchor connecting the photovoltaic solar cell to the substrate. Depending upon the type of receiving substrate used, the photovoltaic solar cell may be removed from the receiving substrate or remain on the receiving substrate for use in the final product.

  1. Photovoltaics: New opportunities for utilities

    SciTech Connect

    Not Available

    1991-07-01

    This publication presents information on photovoltaics. The following topics are discussed: Residential Photovoltaics: The New England Experience Builds Confidence in PV; Austin's 300-kW Photovoltaic Power Station: Evaluating the Breakeven Costs; Residential Photovoltaics: The Lessons Learned; Photovoltaics for Electric Utility Use; Least-Cost Planning: The Environmental Link; Photovoltaics in the Distribution System; Photovoltaic Systems for the Rural Consumer; The Issues of Utility-Intertied Photovoltaics; and Photovoltaics for Large-Scale Use: Costs Ready to Drop Again.

  2. The new alchemy of photovoltaics

    SciTech Connect

    Jeffries, J.P.

    1983-01-01

    The work is a review. The expanding field of use of photovoltaic electric power plants includes single family homes. Solar batteries with a surface area of less than 90 square meters mounted on a roof totally or partially satisfy their daily requirement for electric power. The cost of a single family, approximately 220 square meter home built near Sante Fe and equipped with a passive solar system with a photovoltaic power plant with a power production of 6,500 kilovolthours per year is 190,000 dollars. The cost of a solar battery has been reduced to 7 to 15 dollars per watt of peak power, which is totally insufficient for buy back even over forth years. The threshold of cost, when the solar battery is competitive is 3 dollars per watt. Nevertheless, approximately 6,000 single family dwelling passive solar systems with a photovoltaic power plant are in operation in the United States. The previous opponents of the photovoltaic method, the oil companies, have become suporters of the development and production of solar energy. After the decline in 1982 as a result of the five fold reduction of government financing in works in the field of renewable energy sources, the photovoltaic industry enjoyed a new rise in popularity.

  3. Photovoltaic cell

    SciTech Connect

    Jordan, J.F.; Lampkin, C.M.

    1981-12-08

    A photovoltaic cell has: an electrically conductive substrate, which may be glass having a film of conductive tin oxide; a first layer containing a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure; a second layer forming a heterojunction with the first layer; and suitable electrodes where the heterojunction is formed from a solution containing copper, the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amporphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  4. Photovoltaic concentrator module technology

    NASA Astrophysics Data System (ADS)

    Richards, Elizabeth H.; Chamberlin, Jay L.; Boes, Eldon C.

    Significant developments in the development of photovoltaic (PV) concentrator technology are described. Concentrator cell research, advances in PV concentrator cell technology, and PV concentrator module development are described. Reliability issues currently of concern, including the applicability of wet insulation resistance tests to concentrator modules, correlation of accelerated thermal cycling tests with life expectancy in the field, and the importance of quality assurance during manufacture, are discussed. Two PV concentrator power systems installed in 1989 are discussed. A PV concentrator initiative program established by the DOE is given, and the results of the latest cost study are presented.

  5. Photovoltaic cell and production thereof

    DOEpatents

    Narayanan, Srinivasamohan; Kumar, Bikash

    2008-07-22

    An efficient photovoltaic cell, and its process of manufacture, is disclosed wherein the back surface p-n junction is removed from a doped substrate having an oppositely doped emitter layer. A front surface and edges and optionally the back surface periphery are masked and a back surface etch is performed. The mask is not removed and acts as an anti-reflective coating, a passivating agent, or both. The photovoltaic cell retains an untextured back surface whether or not the front is textured and the dopant layer on the back surface is removed to enhance the cell efficiency. Optionally, a back surface field is formed.

  6. Battery testing for photovoltaic applications

    SciTech Connect

    Hund, T.

    1996-11-01

    Battery testing for photovoltaic (PV) applications is funded at Sandia under the Department of Energy`s (DOE) Photovoltaic Balance of Systems (BOS) Program. The goal of the PV BOS program is to improve PV system component design, operation, reliability, and to reduce overall life-cycle costs. The Sandia battery testing program consists of: (1) PV battery and charge controller market survey, (2) battery performance and life-cycle testing, (3) PV charge controller development, and (4) system field testing. Test results from this work have identified market size and trends, PV battery test procedures, application guidelines, and needed hardware improvements.

  7. Use of plays and field size distributions in minerals management service's assessment of undiscovered domestic petroleum resources

    SciTech Connect

    Lore, G.L.; Pecora, W.C.

    1988-02-01

    The Minerals Management Service (MMS) and the US Geological Survey (USGS) are preparing to publish a joint assessment of the nation's petroleum resources. The MMS is responsible for the assessment of offshore resources of the outer continental shelf (OCS) and exclusive economic zone (EEZ) as part of the MMS leasing mission. A study of the resource assessment methodology of the MMS by the National Academy of Sciences recommended that the size of the smallest field assessed by specified when resource estimates are reported. For the joint MMS/USGS assessment, MMS will estimate an undiscovered resource base above a minimum field size of 1 million BOE for all OCS/EEZ areas. Estimates are also being prepared for undiscovered, economically recoverable resources which employ various minimum field size cutoffs as a function of price/cost relationships, economic projections, and other factors. Both types of estimates use the updated PRESTO III computer-based model to simulate repeated drilling programs of prospect distributions (plays) mapped using proprietary seismic data. Hypothetical, speculative, and stratigraphic-type plays are also modeled using input prospect or field size distributions.

  8. Photovoltaic evaluation study

    NASA Astrophysics Data System (ADS)

    Johnson, G.; Heikkilae, M.; Melasuo, T.; Spanner, S.

    Realizing the value and potential of PV-power as well as the growing need for increased cooperation and sharing of knowledge in the field of photovoltaics, FINNIDA and UNICEF decided to undertake a study of selected PV-projects. There were two main objectives for the study: To gather, compile, evaluate and share information on the photovoltaic technology appropriate to developing countries, and to promote the interest and competence of Finnish research institutes, consultants and manufacturers in photovoltaic development. For this purpose a joint evaluation of significant, primarily UN-supported projects providing for the basic needs of rural communities was undertaken. The Gambia and Kenya offered a variety of such projects, and were chosen as target countries for the study. The projects were chosen to be both comparable and complimentary. In the Gambia, the main subject was a partially integrated health and telecommunications project, but a long-operating drinking water pumping system was also studied. In Kenya, a health project in the Turkana area was examined, and also a large scale water pumping installation for fish farming. Field visits were made in order to verify and supplement the data gathered through document research and earlier investigations. Individual data gathering sheets for the project form the core of this study and are intended to give the necessary information in an organized and accessible format. The findings could practically be condensed into one sentence: PV-systems work very well, if properly designed and installed, but the resources and requirements of the recipients must be considered to a higher degree.

  9. Photovoltaic cell

    SciTech Connect

    Jordan, J. F.; Lampkin, C. M.

    1981-02-03

    A photovoltaic cell is disclosed having an electrically conductive substrate, which may be glass having a film of conductive tin oxide. A first layer contains a suitable semiconductor, which layer has a first component film with an amorphous structure and a second component film with a polycrystalline structure a second layer forms a heterojunction with the first layer suitable electrodes are provided where the heterojunction is formed from a solution containing copper, and the amorphous film component is superposed above an electrically conductive substrate to resist permeation of the copper-containing material to shorting electrical contact with the substrate. The penetration resistant amorphous layer permits a variety of processes to be used in forming the heterojunction with even very thin layers (1-6 mu thick) of underlying polycrystalline semi-conductor materials. In some embodiments, the amorphous-like structure may be formed by the addition of aluminum or zirconium compounds to a solution of cadmium salts sprayed over a heated substrate.

  10. Photovoltaic performance and reliability workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986-1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the U.S., PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  11. Photovoltaic performance and reliability workshop

    SciTech Connect

    Mrig, L.

    1993-12-01

    This workshop was the sixth in a series of workshops sponsored by NREL/DOE under the general subject of photovoltaic testing and reliability during the period 1986--1993. PV performance and PV reliability are at least as important as PV cost, if not more. In the US, PV manufacturers, DOE laboratories, electric utilities, and others are engaged in the photovoltaic reliability research and testing. This group of researchers and others interested in the field were brought together to exchange the technical knowledge and field experience as related to current information in this evolving field of PV reliability. The papers presented here reflect this effort since the last workshop held in September, 1992. The topics covered include: cell and module characterization, module and system testing, durability and reliability, system field experience, and standards and codes.

  12. Photovoltaic Incentive Design Handbook

    SciTech Connect

    Hoff, T. E.

    2006-12-01

    Investments in customer-owned grid-connected photovoltaic (PV) energy systems are growing at a steady pace. This is due, in part, to the availability of attractive economic incentives offered by public state agencies and utilities. In the United States, these incentives have largely been upfront lump payments tied to the system capacity rating. While capacity-based ''buydowns'' have stimulated the domestic PV market, they have been criticized for subsidizing systems with potentially poor energy performance. As a result, the industry has been forced to consider alternative incentive structures, particularly ones that pay based on long-term measured performance. The industry, however, lacks consensus in the debate over the tradeoffs between upfront incentive payments versus longer-term payments for energy delivery. This handbook is designed for agencies and utilities that offer or intend to offer incentive programs for customer-owned PV systems. Its purpose is to help select, design, and implement incentive programs that best meet programmatic goals. The handbook begins with a discussion of the various available incentive structures and then provides qualitative and quantitative tools necessary to design the most appropriate incentive structure. It concludes with program administration considerations.

  13. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell.

    PubMed

    Petterson, Maureen K; Lemaitre, Maxime G; Shen, Yu; Wadhwa, Pooja; Hou, Jie; Vasilyeva, Svetlana V; Kravchenko, Ivan I; Rinzler, Andrew G

    2015-09-30

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separated there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm(2) AM1.5G illumination, results in a short-circuit current density of 35 mA/cm(2) and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. A deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented. PMID:26352052

  14. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell

    DOE PAGESBeta

    Petterson, Maureen K.; Lemaitre, Maxime G.; Shen, Yu; Wadhwa, Pooja; Hou, Jie; Vasilyeva, Svetlana V.; Kravchenko, Ivan I.; Rinzler, Andrew G.

    2015-09-09

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separatedmore » there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm2 AM1.5G illumination, results in a short-circuit current density of 35 mA/cm2 and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. Finally, a deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented.« less

  15. On Field-Effect Photovoltaics: Gate Enhancement of the Power Conversion Efficiency in a Nanotube/Silicon-Nanowire Solar Cell

    SciTech Connect

    Petterson, Maureen K.; Lemaitre, Maxime G.; Shen, Yu; Wadhwa, Pooja; Hou, Jie; Vasilyeva, Svetlana V.; Kravchenko, Ivan I.; Rinzler, Andrew G.

    2015-09-09

    Recent years have seen a resurgence of interest in crystalline silicon Schottky junction solar cells distinguished by the use of low density of electronic states (DOS) nanocarbons (nanotubes, graphene) as the metal contacting the Si. Recently, unprecedented modulation of the power conversion efficiency in a single material system has been demonstrated in such cells by the use of electronic gating. The gate field induced Fermi level shift in the low-DOS carbon serves to enhance the junction built-in potential, while a gate field induced inversion layer at the Si surface, in regions remote from the junction, keeps the photocarriers well separated there, avoiding recombination at surface traps and defects (a key loss mechanism). Here, we extend these results into the third dimension of a vertical Si nanowire array solar cell. A single wall carbon nanotube layer engineered to contact virtually each n-Si nanowire tip extracts the minority carriers, while an ionic liquid electrolytic gate drives the nanowire body into inversion. The enhanced light absorption of the vertical forest cell, at 100 mW/cm2 AM1.5G illumination, results in a short-circuit current density of 35 mA/cm2 and associated power conversion efficiency of 15%. These results highlight the use of local fields as opposed to surface passivation as a means of avoiding front surface recombination. Finally, a deleterious electrochemical reaction of the silicon due to the electrolyte gating is shown to be caused by oxygen/water entrained in the ionic liquid electrolyte. While encapsulation can avoid the issue, a nonencapsulation-based approach is also implemented.

  16. Enhanced performance of photodetector and photovoltaic based on carrier reflector and back surface field generated by doped graphene

    NASA Astrophysics Data System (ADS)

    Chang, Che-Wei; Wang, Di-Yan; Tan, Wei-Chun; Huang, I.-Sheng; Wang, I.-Sheng; Chen, Chia-Chun; Yang, Ying-Jay; Chen, Yang-Fang

    2012-08-01

    We report the influence of carrier reflector and back surface field generated by doped graphene on n-ZnO nanoridges/p-silicon photodetectors and silicon solar cells. It is found that the p-type graphene not only acts as an electron blocking layer, but also helps the collection of photogenerated holes. Quite surprisingly, the on/off ratio of the photodetector with the insertion of doped graphene can be increased by up to 40 times. Moreover, we demonstrate that typical silicon solar cells with the doped graphene, the cell efficiency can be enhanced by about 20%. Our approach would expand numerous applications for graphene-based optoelectronic devices.

  17. Photovoltaic roof construction

    SciTech Connect

    Hawley, W.W.

    1980-02-26

    In a batten-seam roof construction employing at least one photovoltaic cell module, the electrical conduits employed with the at least one photovoltaic cell module are disposed primarily under the battens of the roof.

  18. Thermionic photovoltaic energy converter

    NASA Technical Reports Server (NTRS)

    Chubb, D. L. (Inventor)

    1985-01-01

    A thermionic photovoltaic energy conversion device comprises a thermionic diode mounted within a hollow tubular photovoltaic converter. The thermionic diode maintains a cesium discharge for producing excited atoms that emit line radiation in the wavelength region of 850 nm to 890 nm. The photovoltaic converter is a silicon or gallium arsenide photovoltaic cell having bandgap energies in this same wavelength region for optimum cell efficiency.

  19. Photovoltaic device and method

    DOEpatents

    Cleereman, Robert J; Lesniak, Michael J; Keenihan, James R; Langmaid, Joe A; Gaston, Ryan; Eurich, Gerald K; Boven, Michelle L

    2015-01-27

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  20. Amorphous silicon photovoltaic devices

    SciTech Connect

    Carlson, David E.; Lin, Guang H.; Ganguly, Gautam

    2004-08-31

    This invention is a photovoltaic device comprising an intrinsic or i-layer of amorphous silicon and where the photovoltaic device is more efficient at converting light energy to electric energy at high operating temperatures than at low operating temperatures. The photovoltaic devices of this invention are suitable for use in high temperature operating environments.

  1. Photovoltaic device and method

    SciTech Connect

    Cleereman, Robert; Lesniak, Michael J.; Keenihan, James R.; Langmaid, Joe A.; Gaston, Ryan; Eurich, Gerald K.; Boven, Michelle L.

    2015-11-24

    The present invention is premised upon an improved photovoltaic device ("PVD") and method of use, more particularly to an improved photovoltaic device with an integral locator and electrical terminal mechanism for transferring current to or from the improved photovoltaic device and the use as a system.

  2. Influence of Magnetic Field on the Mesoporous Structure of Fe-Cu Compounds in Dye-Sensitized Photovoltaic Cells

    NASA Astrophysics Data System (ADS)

    Alami, Abdul Hai; Zhang, Di; Aokal, Camilia; Abed, Jehad; Abdoun, Ideisan Abu; Alawadhi, Hussain

    2016-03-01

    This paper investigates the effect of applying static and dynamic magnetic fields on the deposition of Fe-Cu compound on the working electrode of a dye-sensitized solar cell. The deposition of this compound on glass is complicated due to the fact that it cannot be evaporated or sintered beyond the dissociation temperature of 973 K (700 °C), and the doctor blade technique causes detrimental layer inconsistencies. The Fe-Cu compound is relatively easy to produce and is significantly cheaper and more absorptive (>81 pct) in the Vis-NIR than the standard TiO2 mesoporous material used for solar cells. It also behaves as a semiconductor due to the high diffusion of the Fe into the Cu lattice that a bandgap of 1.8 eV is obtained. The use of a Schiff base dye with a compatible bandgap of 1.68 eV is used as a sensitizer for the production of a test cell that generated more photocurrent than its TiO2 counterpart, which is a promising result for an alternative mesoporous layer in solar cells.

  3. Transparent ultraviolet photovoltaic cells.

    PubMed

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future. PMID:26872163

  4. NREL Photovoltaic Program FY 1993

    SciTech Connect

    Not Available

    1994-08-01

    This report reviews the in-house and subcontracted research and development (R&D) activities under the National Renewable Energy Laboratory (NREL) Photovoltaic (PV) Program from October 1, 1992, through September 30, 1993 (fiscal year [FY] 1993). The NREL PV Program is part of the U.S. Department of Energy`s (DOE`s) National Photovoltaics Program, as described in the DOE Photovoltaics Program Plan, FY 1991 - FY 1995. The FY 1993 budget authority (BA) for carrying out the NREL PV Program was $40.1 million in operating funds and $0.9 million in capital equipment funds. An additional $4.8 million in capital equipment funds were made available for the new Solar Energy Research Facility (SERF) that will house the in-house PV laboratories beginning in FY 1994. Subcontract activities represent a major part of the NREL PV Program, with more than $23.7 million (nearly 59%) of the FY 1993 operating funds going to 70 subcontractors. In FY 1993, DOE assigned certain other PV subcontracting efforts to the DOE Golden Field Office (DOE/GO), and assigned responsibility for their technical support to the NREL PV Program. An example is the PV:BONUS (Building Opportunities in the U.S. for Photovoltaics) Project. These DOE/GO efforts are also reported in this document.

  5. Photovoltaics Performance and Reliability Workshop

    NASA Astrophysics Data System (ADS)

    Mrig, L.

    This document consists of papers and viewgraphs compiled from the proceedings of a workshop held in September 1992. This workshop was the fifth in a series sponsored by NREL/DOE under the general subject areas of photovoltaic module testing and reliability. PV manufacturers, DOE laboratories, electric utilities, and others exchanged technical knowledge and field experience. The topics of cell and module characterization, module and system performance, materials and module durability/reliability research, solar radiation, and applications are discussed.

  6. Photovoltaic refrigeration application: Assessment of the near-term market

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.; Bifano, W. J.; Poley, W. A.; Scudder, L. R.

    1977-01-01

    This foreign and domestic market assessment was performed as part of the Tests and Applications Project being conducted by NASA-LeRC as part of the Department of Energy's (DOE) National Photovoltaic Program. One of the objectives of that program was to stimulate the demand for photovoltaic power systems so that appropriate markets would be developed in concert with the increasing photovoltaic production capacity. The refrigeration application represented a possible market for photovoltaics; hence, a brief survey of potential applications was conducted. Both refrigerators and refrigeration systems were considered in the assessment although the primary emphasis is on refrigerators of 9 cu ft of less. Three user sectors were examined: (1) government, (2) commercial/institutional, and (3) general public.

  7. Residential photovoltaic system designs

    SciTech Connect

    Russell, M. C.

    1981-01-01

    A project to develop Residential Photovoltaic Systems has begun at Massachusetts Institute of Technology Lincoln Laboratory with the construction and testing of five Prototype Systems. All of these systems utilize a roof-mounted photovoltaic array and allow excess solar-generated electric energy to be fed back to the local utility grid, eliminating the need for on-site storage. Residential photovoltaic system design issues are discussed and specific features of the five Prototype Systems now under test are presented.

  8. Photovoltaic technology assessment

    SciTech Connect

    Backus, C.E.

    1981-01-01

    After a brief review of the history of photovoltaic devices and a discussion of the cost goals set for photovoltaic modules, the status of photovoltaic technology is assessed. Included are discussions of: current applications, present industrial production, low-cost silicon production techniques, energy payback periods for solar cells, advanced materials research and development, concentrator systems, balance-of-system components. Also discussed are some nontechnical aspects, including foreign markets, US government program approach, and industry attitudes and approaches. (LEW)

  9. Photovoltaic research and development in Japan

    NASA Astrophysics Data System (ADS)

    Shimada, K.

    1983-02-01

    The status of the Japanese photovoltaic (PV) R&D activities was surveyed through literature searches, private communications, and site visits in 1982. The results show that the Japanese photovoltaic technology is maturing rapidly, consistent with the steady government funding under the Sunshine Project. Two main thrusts of the Project are: (1) completion of the solar panel production pilot plants using cast ingot and sheet silicon materials, and (2) development of large area amorphous silicon solar cells with acceptable efficiency (10 to 12%). An experimental automated solar panel production plant rated at 500 kW/yr is currently under construction for the Sunshine Project for completion in March 1983. Efficiencies demonstrated by experimental large are amorphous silicon solar cells are approaching 8%. Small area amorphous silicon solar cells are, however, currently being mass produced and marketed by several companies at an equivalent annual rate of 2 MW/yr for consumer electronic applications. There is no evidence of an immediate move by the Japanese PV industry to enter extensively into the photovoltaic power market, domestic or otherwise. However, the photovoltaic technology itself could become ready for such an entry in the very near future, especially by making use of advanced process automation technologies.

  10. Photovoltaic research and development in Japan

    NASA Technical Reports Server (NTRS)

    Shimada, K.

    1983-01-01

    The status of the Japanese photovoltaic (PV) R&D activities was surveyed through literature searches, private communications, and site visits in 1982. The results show that the Japanese photovoltaic technology is maturing rapidly, consistent with the steady government funding under the Sunshine Project. Two main thrusts of the Project are: (1) completion of the solar panel production pilot plants using cast ingot and sheet silicon materials, and (2) development of large area amorphous silicon solar cells with acceptable efficiency (10 to 12%). An experimental automated solar panel production plant rated at 500 kW/yr is currently under construction for the Sunshine Project for completion in March 1983. Efficiencies demonstrated by experimental large are amorphous silicon solar cells are approaching 8%. Small area amorphous silicon solar cells are, however, currently being mass produced and marketed by several companies at an equivalent annual rate of 2 MW/yr for consumer electronic applications. There is no evidence of an immediate move by the Japanese PV industry to enter extensively into the photovoltaic power market, domestic or otherwise. However, the photovoltaic technology itself could become ready for such an entry in the very near future, especially by making use of advanced process automation technologies.

  11. On the plasmonic photovoltaic.

    PubMed

    Mubeen, Syed; Lee, Joun; Lee, Woo-Ram; Singh, Nirala; Stucky, Galen D; Moskovits, Martin

    2014-06-24

    The conversion of sunlight into electricity by photovoltaics is currently a mature science and the foundation of a lucrative industry. In conventional excitonic solar cells, electron-hole pairs are generated by light absorption in a semiconductor and separated by the "built in" potential resulting from charge transfer accompanying Fermi-level equalization either at a p-n or a Schottky junction, followed by carrier collection at appropriate electrodes. Here we report a stable, wholly plasmonic photovoltaic device in which photon absorption and carrier generation take place exclusively in the plasmonic metal. The field established at a metal-semiconductor Schottky junction separates charges. The negative carriers are high-energy (hot) electrons produced immediately following the plasmon's dephasing. Some of the carriers are energetic enough to clear the Schottky barrier or quantum mechanically tunnel through it, thereby producing the output photocurrent. Short circuit photocurrent densities in the range 70-120 μA cm(-2) were obtained for simulated one-sun AM1.5 illumination with devices based on arrays of parallel gold nanorods, conformally coated with 10 nm TiO2 films and fashioned with a Ti metal collector. For the device with short circuit currents of 120 μA cm(-2), the internal quantum efficiency is ∼2.75%, and its wavelength response tracks the absorption spectrum of the transverse plasmon of the gold nanorods indicating that the absorbed photon-to-electron conversion process resulted exclusively in the Au, with the TiO2 playing a negligible role in charge carrier production. Devices fabricated with 50 nm TiO2 layers had open-circuit voltages as high as 210 mV, short circuit current densities of 26 μA cm(-2), and a fill factor of 0.3. For these devices, the TiO2 contributed a very small but measurable fraction of the charge carriers. PMID:24861280

  12. Photovoltaic research opportunities. Final report

    SciTech Connect

    Macaleer, B.; Bowers, J.; Hurlburt, B.

    1985-11-19

    The purpose of this study is to identify opportunities for photovoltaic (PV) research projects to capitalize on related but non-PV research. The study is performed under the assumption that a considerable body of ongoing semiconductor research in non-PV areas could be of value to its PV Program and the PV community in general. Research related to III-V compounds, thin films, and crystalline silicon materials is included. Research that is known to be PV-related or sponsored by DOE was excluded from consideration. The study resulted in 11 recommendations (research areas) and a subset of 58 specific research projects. In addition, over 75 non-PV research managers in the semiconductor field are identified as potential sources of ideas which could benefit photovoltaics.

  13. Orthogonal Thin Film Photovoltaics on Vertical Nanostructures.

    PubMed

    Ahnood, Arman; Zhou, H; Suzuki, Y; Sliz, R; Fabritius, T; Nathan, Arokia; Amaratunga, G A J

    2015-12-01

    Decoupling paths of carrier collection and illumination within photovoltaic devices is one promising approach for improving their efficiency by simultaneously increasing light absorption and carrier collection efficiency. Orthogonal photovoltaic devices are core-shell type structures consisting of thin film photovoltaic stack on vertical nanopillar scaffolds. These types of devices allow charge collection to take place in the radial direction, perpendicular to the path of light in the vertical direction. This approach addresses the inherently high recombination rate of disordered thin films, by allowing semiconductor films with minimal thicknesses to be used in photovoltaic devices, without performance degradation associated with incomplete light absorption. This work considers effects which influence the performance of orthogonal photovoltaic devices. Illumination non-uniformity as light travels across the depth of the pillars, electric field enhancement due to the nanoscale size and shape of the pillars, and series resistance due to the additional surface structure created through the use of pillars are considered. All of these effects influence the operation of orthogonal solar cells and should be considered in the design of vertically nanostructured orthogonal photovoltaics. PMID:26676997

  14. Orthogonal Thin Film Photovoltaics on Vertical Nanostructures

    NASA Astrophysics Data System (ADS)

    Ahnood, Arman; Zhou, H.; Suzuki, Y.; Sliz, R.; Fabritius, T.; Nathan, Arokia; Amaratunga, G. A. J.

    2015-12-01

    Decoupling paths of carrier collection and illumination within photovoltaic devices is one promising approach for improving their efficiency by simultaneously increasing light absorption and carrier collection efficiency. Orthogonal photovoltaic devices are core-shell type structures consisting of thin film photovoltaic stack on vertical nanopillar scaffolds. These types of devices allow charge collection to take place in the radial direction, perpendicular to the path of light in the vertical direction. This approach addresses the inherently high recombination rate of disordered thin films, by allowing semiconductor films with minimal thicknesses to be used in photovoltaic devices, without performance degradation associated with incomplete light absorption. This work considers effects which influence the performance of orthogonal photovoltaic devices. Illumination non-uniformity as light travels across the depth of the pillars, electric field enhancement due to the nanoscale size and shape of the pillars, and series resistance due to the additional surface structure created through the use of pillars are considered. All of these effects influence the operation of orthogonal solar cells and should be considered in the design of vertically nanostructured orthogonal photovoltaics.

  15. Microsystems Enabled Photovoltaics

    ScienceCinema

    Gupta, Vipin; Nielson, Greg; Okandan, Murat, Granata, Jennifer; Nelson, Jeff; Haney, Mike; Cruz-Campa, Jose Luiz

    2014-06-23

    Sandia's microsystems enabled photovoltaic advances combine mature technology and tools currently used in microsystem production with groundbreaking advances in photovoltaics cell design, decreasing production and system costs while improving energy conversion efficiency. The technology has potential applications in buildings, houses, clothing, portable electronics, vehicles, and other contoured structures.

  16. Handbook for photovoltaic cabling

    SciTech Connect

    Klein, D. N.

    1980-08-01

    This volume, originally written as part of the Interim Performance Criteria Document Development Implementation Plan and Procedures for Photovoltaic Energy Systems, is an analysis of the several factors to be considered in selecting cabling for photovoltaic purposes. These factors, correspoonding to chapter titles, are electrical, structural, safety, durability/reliability, and installation. A glossary of terms used within the volume is included for reference.

  17. Solar Photovoltaic Energy.

    ERIC Educational Resources Information Center

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

    The goals of solar photovoltaic technology in contributing to America's future energy needs are presented in this study conducted by the American Physical Society. Although the time needed for photovoltaics to become popular is several decades away, according to the author, short-range applications are given. (Author/SA)

  18. Solar Photovoltaic Cells.

    ERIC Educational Resources Information Center

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  19. Microsystems Enabled Photovoltaics

    SciTech Connect

    Gupta, Vipin; Nielson, Greg; Okandan, Murat, Granata, Jennifer; Nelson, Jeff; Haney, Mike; Cruz-Campa, Jose Luiz

    2012-07-02

    Sandia's microsystems enabled photovoltaic advances combine mature technology and tools currently used in microsystem production with groundbreaking advances in photovoltaics cell design, decreasing production and system costs while improving energy conversion efficiency. The technology has potential applications in buildings, houses, clothing, portable electronics, vehicles, and other contoured structures.

  20. Endurance Tests Of Amorphous-Silicon Photovoltaic Modules

    NASA Technical Reports Server (NTRS)

    Ross, Ronald G., Jr.; Sugimura, Russell S.

    1989-01-01

    Failure mechanisms in high-power service studied. Report discusses factors affecting endurance of amorphous-silicon solar cells. Based on field tests and accelerated aging of photovoltaic modules. Concludes that aggressive research needed if amorphous-silicon modules to attain 10-year life - value U.S. Department of Energy established as goal for photovoltaic modules in commercial energy-generating plants.

  1. Molecular Photovoltaics in Nanoscale Dimension

    PubMed Central

    Burtman, Vladimir; Zelichonok, Alexander; Pakoulev, Andrei V.

    2011-01-01

    This review focuses on the intrinsic charge transport in organic photovoltaic (PVC) devices and field-effect transistors (SAM-OFETs) fabricated by vapor phase molecular self-assembly (VP-SAM) method. The dynamics of charge transport are determined and used to clarify a transport mechanism. The 1,4,5,8-naphthalene-tetracarboxylic diphenylimide (NTCDI) SAM devices provide a useful tool to study the fundamentals of polaronic transport at organic surfaces and to discuss the performance of organic photovoltaic devices in nanoscale. Time-resolved photovoltaic studies allow us to separate the charge annihilation kinetics in the conductive NTCDI channel from the overall charge kinetic in a SAM-OFET device. It has been demonstrated that tuning of the type of conductivity in NTCDI SAM-OFET devices is possible by changing Si substrate doping. Our study of the polaron charge transfer in organic materials proposes that a cation-radical exchange (redox) mechanism is the major transport mechanism in the studied SAM-PVC devices. The role and contribution of the transport through delocalized states of redox active surface molecular aggregates of NTCDI are exposed and investigated. This example of technological development is used to highlight the significance of future technological development of nanotechnologies and to appreciate a structure-property paradigm in organic nanostructures. PMID:21339983

  2. Giant photovoltaic effects driven by residual polar field within unit-cell-scale LaAlO3 films on SrTiO3

    PubMed Central

    Liang, Haixing; Cheng, Long; Zhai, Xiaofang; Pan, Nan; Guo, Hongli; Zhao, Jin; Zhang, Hui; Li, Lin; Zhang, Xiaoqiang; Wang, Xiaoping; Zeng, Changgan; Zhang, Zhenyu; Hou, J. G.

    2013-01-01

    For polar/nonpolar heterostructures, Maxwell's theory dictates that the electric potential in the polar components will increase divergently with the film thickness. For LaAlO3/SrTiO3, a conceptually intriguing route, termed charge reconstruction, has been proposed to avert such “polar catastrophe”. The existence of a polar potential in LaAlO3 is a prerequisite for the validity of the charge reconstruction picture, yet to date, its direct measurement remains a major challenge. Here we establish unambiguously the existence of the residual polar potential in ultrathin LaAlO3 films on SrTiO3, using a novel photovoltaic device design as an effective probe. The measured lower bound of the residual polar potential is 1.0 V. Such a direct observation of the giant residual polar potential within the unit-cell-scale LaAlO3 films amounts to a definitive experimental evidence for the charge reconstruction picture, and also points to new technological significance of oxide heterostructures in photovoltaic and sensing devices with atomic-scale control. PMID:23756918

  3. PV Standards Work: Photovoltaic System and Component Certification, Test Facility Accreditation, and Solar Photovoltaic Energy Systems International Standards

    SciTech Connect

    Basso, T. S.; Chalmers, S.; Barikmo, H. O.

    2005-11-01

    This paper discusses efforts led by two companies (PowerMark Corporation and Sunset Technologies Inc.) to support both U.S. domestic and international photovoltaic (PV) system and component certification and test facility accreditation programs and the operation of the International Electrotechnical Commission (IEC) Technical Committee 82 (TC-82) Photovoltaic Energy Systems. International and national PV certification/accreditation programs are successfully facilitating entry of only the highest quality PV products into the marketplace. Standards also continue to be a cornerstone for assuring global PV product conformity assessment, reducing non-tariff trade barriers, and ultimately improving PV products while lowering cost.

  4. Photovoltaic panel-generator based autonomous power source for small refrigeration units

    SciTech Connect

    Kattakayam, T.A.; Srinivasan, K.

    1996-06-01

    This article describes an autonomous power source for a domestic refrigeration unit which is powered by a field of photovoltaic panels backed-up by a generator set. Salient design features and results from some of the tests on the unit are presented. methodologies for reliable and efficient operation of the refrigerator have been evolved. A finite time delay between cut-out and cut-in of the compressor, changes in invertor design to meet the demands at start and at run of the motor, choice of battery capacity so as to eliminate the need for a power conditioner are found to result in energy conservation. The entire unit has been made from indigenously available components and uses minimal electronic controls. Such units have applications for the storage of vaccines and life saving medicines which require uninterrupted refrigeration, in medical shops, rural health centres, veterinary laboratories, etc. 12 refs., 13 figs.

  5. Photovoltaic systems and applications perspective

    SciTech Connect

    Jones, G.J.

    1980-01-01

    The National Photovoltaic Program is currently in the process of increasing emphasis on full-scale system experiments in the potential user environment, a natural coccurrence in the evolution of system design and development. At this point large amounts of design information are available and need to be brought together in usable form to support this effort. The state of understanding in the system definition area for the major applications is reviewed, and the remaining issues, especially as they impact the field test activities, are indicated.

  6. Singlet exciton fission photovoltaics.

    PubMed

    Lee, Jiye; Jadhav, Priya; Reusswig, Philip D; Yost, Shane R; Thompson, Nicholas J; Congreve, Daniel N; Hontz, Eric; Van Voorhis, Troy; Baldo, Marc A

    2013-06-18

    Singlet exciton fission, a process that generates two excitons from a single photon, is perhaps the most efficient of the various multiexciton-generation processes studied to date, offering the potential to increase the efficiency of solar devices. But its unique characteristic, splitting a photogenerated singlet exciton into two dark triplet states, means that the empty absorption region between the singlet and triplet excitons must be filled by adding another material that captures low-energy photons. This has required the development of specialized device architectures. In this Account, we review work to develop devices that harness the theoretical benefits of singlet exciton fission. First, we discuss singlet fission in the archetypal material, pentacene. Pentacene-based photovoltaic devices typically show high external and internal quantum efficiencies. They have enabled researchers to characterize fission, including yield and the impact of competing loss processes, within functional devices. We review in situ probes of singlet fission that modulate the photocurrent using a magnetic field. We also summarize studies of the dissociation of triplet excitons into charge at the pentacene-buckyball (C60) donor-acceptor interface. Multiple independent measurements confirm that pentacene triplet excitons can dissociate at the C60 interface despite their relatively low energy. Because triplet excitons produced by singlet fission each have no more than half the energy of the original photoexcitation, they limit the potential open circuit voltage within a solar cell. Thus, if singlet fission is to increase the overall efficiency of a solar cell and not just double the photocurrent at the cost of halving the voltage, it is necessary to also harvest photons in the absorption gap between the singlet and triplet energies of the singlet fission material. We review two device architectures that attempt this using long-wavelength materials: a three-layer structure that uses

  7. Photonic Design for Photovoltaics

    SciTech Connect

    Kosten, E.; Callahan, D.; Horowitz, K.; Pala, R.; Atwater, H.

    2014-08-28

    We describe photonic design approaches for silicon photovoltaics including i) trapezoidal broadband light trapping structures ii) broadband light trapping with photonic crystal superlattices iii) III-V/Si nanowire arrays designed for broadband light trapping.

  8. Photovoltaic solar cell

    DOEpatents

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  9. Photovoltaic solar cell

    DOEpatents

    Nielson, Gregory N; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J

    2014-05-20

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electricity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  10. Photovoltaic systems test facility

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Facility provides broad and flexible capability for evaluating photovoltaic systems and design concepts. As 'breadboard' system, it can be used to check out complete systems, subsystems, and components before installation in actual service.

  11. Photovoltaic systems and applications

    SciTech Connect

    Not Available

    1982-01-01

    Abstracts are given of presentations given at a project review meeting held at Albuquerque, NM. The proceedings cover the past accomplishments and current activities of the Photovoltaic Systems Research, Balance-of-System Technology Development and System Application Experiments Projects at Sandia National Laboratories. The status of intermediate system application experiments and residential system analysis is emphasized. Some discussion of the future of the Photovoltaic Program in general, and the Sandia projects in particular is also presented.

  12. Lightweight Solar Photovoltaic Blankets

    NASA Technical Reports Server (NTRS)

    Ceragioli, R.; Himmler, R.; Nath, P.; Vogeli, C.; Guha, S.

    1995-01-01

    Lightweight, flexible sheets containing arrays of stacked solar photovoltaic cells developed to supply electric power aboard spacecraft. Solar batteries satisfying stringent requirements for operation in outer space also adaptable to terrestrial environment. Attractive for use as long-lived, portable photovoltaic power sources. Cells based on amorphous silicon which offers potential for order-of-magnitude increases in power per unit weight, power per unit volume, and endurance in presence of ionizing radiation.

  13. Tandem junction amorphous semiconductor photovoltaic cell

    DOEpatents

    Dalal, Vikram L.

    1983-01-01

    A photovoltaic stack comprising at least two p.sup.+ i n.sup.+ cells in optical series, said cells separated by a transparent ohmic contact layer(s), provides a long optical path for the absorption of photons while preserving the advantageous field-enhanced minority carrier collection arrangement characteristic of p.sup.+ i n.sup.+ cells.

  14. Tandem junction amorphous semiconductor photovoltaic cell

    DOEpatents

    Dalal, V.L.

    1983-06-07

    A photovoltaic stack comprising at least two p[sup +]i n[sup +] cells in optical series, said cells separated by a transparent ohmic contact layer(s), provides a long optical path for the absorption of photons while preserving the advantageous field-enhanced minority carrier collection arrangement characteristic of p[sup +]i n[sup +] cells. 3 figs.

  15. Photovoltaic module and interlocked stack of photovoltaic modules

    DOEpatents

    Wares, Brian S.

    2014-09-02

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame. A plurality of individual male alignment features and a plurality of individual female alignment features are included on each frame. Adjacent photovoltaic modules are interlocked by multiple individual male alignment features on a first module of the adjacent photovoltaic modules fitting into and being surrounded by corresponding individual female alignment features on a second module of the adjacent photovoltaic modules. Other embodiments, features and aspects are also disclosed.

  16. Subsystem engineering and development of grid-connected photovoltaic systems

    SciTech Connect

    Burgess, E.L.; Post, H.N.; Key, T.S.

    1982-01-01

    The experience gained in fielding residential and intermediate sized photovoltaic application experiments is summarized. This experience is used to guide the engineering and development of array and power conditioning subsystems for grid-connected photovoltaic systems. A major consideration in this development effort is cost. Through innovative engineering, using a modular building block approach for the array subsystem, it is now possible to construct array fields, in moderate quantities, for about $52/m/sup 2/ excluding the photovoltaic modules. Similarly, results of power conditioning subsystem development indicate a projected cost of about $0.25/W/sub p/ for advanced units with conversion efficiencies in excess of 90%.

  17. Standards for photovoltaic energy conversion systems. Final report

    SciTech Connect

    Schafft, H. A.

    1980-04-01

    This report provides the results of a search for existing domestic standards and related documents for possible application in the development of a standards base for photovoltaic energy conversion systems. The search resulted in locating about 150 test methods, recommended practices, standards, solar-thermal performance criteria, and other standards-related documents. They are listed by topic areas in the appendix. The listing was prepared to assist those involved in developing performance criteria for photovoltaic systems and in identifying methods to test system performance against these criteria. It is clear from the results of the search that few standards are directly applicable to terrestrial solar photovoltaic systems and that much standards development is required to support the commercialization of such systems.

  18. Photovoltaic water pumping applications: Assessment of the near-term market

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.; Bifano, W. J.; Scudder, L. R.; Poley, W. A.; Cusick, J. P.

    1978-01-01

    Water pumping applications represent a potential market for photovoltaics. The price of energy for photovoltaic systems was compared to that of utility line extensions and diesel generators. The potential domestic demand was defined in the government, commercial/institutional and public sectors. The foreign demand and sources of funding for water pumping systems in the developing countries were also discussed briefly. It was concluded that a near term domestic market of at least 240 megawatts and a foreign market of about 6 gigawatts exist.

  19. Photovoltaic village power application: Assessment of the near-term market

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.; Bifano, W. J.; Poley, W. A.; Scudder, L. R.

    1978-01-01

    The village power application represents a potential market for photovoltaics. The price of energy for photovoltaic systems was compared to that of utility line extensions and diesel generators. The potential domestic demand was defined in both the government and commercial sectors. The foreign demand and sources of funding for village power systems in the developing countries were also discussed briefly. It was concluded that a near term domestic market of at least 12 MW min and a foreign market of about 10 GW exists.

  20. Research Opportunities in Reliability of Photovoltaic Modules (Presentation)

    SciTech Connect

    Hacke, P.

    2010-05-01

    The motivation for an increased scope and a more proactive effort in reliability research of photovoltaic modules and systems includes reducing the levelized cost of energy and gaining better confidence in the energy and financial payback for photovoltaic systems. This increased reliability and confidence will lead to greater penetration of photovoltaics in the energy portfolio and greater employment in photovoltaics and related industries. Present research needs include the fundamental degradation mechanisms of polymers, connectors and other module components, mapping of failure mechanisms observed in the field to those in accelerated lifetime tests, determining the acceleration factors, and improving standards for modules such that tests can appropriately be assigned to evaluate their long term durability. Specific mechanisms discussed are corrosion in module components, metastability in thin-film active layers, delamination and loss of elastic properties in module polymeric materials, and inverter failure. Presently, there is hiring of reliability scientists and engineers at many levels of the value chain for photovoltaics.

  1. Photovoltaic roof system

    SciTech Connect

    Nath, P.; Laarman, T.; Singh, A.

    1993-08-03

    A modular batten and seam type photovoltaic roofing system is described comprising: (1) a plurality of photovoltaic panels, each panel including: a base member having a generally planar central portion at least partially bounded by two upturned flanges; a photovoltaic device disposed on the central portion, the device including a positive terminal and a negative terminal; a positive terminal region associated with the base member and including a first electrical conductor in electrical communication with the positive terminal of the photovoltaic device; a negative terminal region associated with the base member and including a second electrical conductor in electrical communication with the negative terminal of the photovoltaic device; a first electrical connector affixed to the positive terminal region, in electrical communication with the first electrical conductor; a second electrical conductor affixed to the negative terminal region, in electrical communication with the second electrical conductor; the roofing system further including: (2) a coupling member having a first end reversibly attachable to one of the electrical connectors on a first one of the plurality of panels and a second end reversibly attachable to one of the electrical connectors on a second one of the panels, the coupling member being operable to establish electrical communication between the first and second panels; (3) a plurality of batten members, each configured to cover one upturned flange of each of two of the plurality of panels, when the two panels are adjacently disposed on a roof.

  2. Nanowires enabling strained photovoltaics

    SciTech Connect

    Greil, J.; Bertagnolli, E.; Lugstein, A.; Birner, S.

    2014-04-21

    Photovoltaic nano-devices have largely been relying on charge separation in conventional p-n junctions. Junction formation via doping, however, imposes major challenges in process control. Here, we report on a concept for photovoltaic energy conversion at the nano scale without the need for intentional doping. Our approach relies on charge carrier separation in inhomogeneously strained germanium nanowires (Ge NWs). This concept utilizes the strain-induced gradient in bandgap along tapered NWs. Experimental data confirms the feasibility of strain-induced charge separation in individual vapor-liquid-solid grown Ge NW devices with an internal quantum efficiency of ∼5%. The charge separation mechanism, though, is not inherently limited to a distinct material. Our work establishes a class of photovoltaic nano-devices with its opto-electronic properties engineered by size, shape, and applied strain.

  3. Photovoltaic Subcontract Program

    SciTech Connect

    Surek, Thomas; Catalano, Anthony

    1993-03-01

    This report summarizes the fiscal year (FY) 1992 progress of the subcontracted photovoltaic (PV) research and development (R D) performed under the Photovoltaic Advanced Research and Development Project at the National Renewable Energy Laboratory (NREL)-formerly the Solar Energy Research Institute (SERI). The mission of the national PV program is to develop PV technology for large-scale generation of economically competitive electric power in the United States. The technical sections of the report cover the main areas of the subcontract program: the Crystalline Materials and Advanced Concepts project, the Polycrystalline Thin Films project, Amorphous Silicon Research project, the Photovoltaic Manufacturing Technology (PVMaT) project, PV Module and System Performance and Engineering project, and the PV Analysis and Applications Development project. Technical summaries of each of the subcontracted programs provide a discussion of approaches, major accomplishments in FY 1992, and future research directions.

  4. Photovoltaic concentrator research progress

    SciTech Connect

    Arvizu, D.E.

    1985-01-01

    This paper provides a review of progress in the DOE sponsored, Sandia managed Photovoltaic Concentrator Research Project. Research status, project goals and a discussion of concentrator economics is presented. Recent research accomplishments that will be discussed include 21% efficient baseline silicon cells by Applied Solar Energy Corporation and Sandia, 26% efficient GaAs cells by Varian Associates, and near 25% mechanically stacked multijunction GaAs/Si cells by Hughes Research, Applied Solar, and Sandia. In addition, improvements in breadboard module units (i.e. single lens/cell combination) such as a 19% GaAs unit by Varian and a near 17% silicon unit by ENTECH will be reviewed. This paper concludes that the photovoltaic concentrator option is making excellent progress toward competitive cost-effectiveness and provides a strong photovoltaic alternative.

  5. Designing future photovoltaic systems

    SciTech Connect

    Jones, G.J.

    1984-01-01

    The large scale use of photovoltaic systems to generate our electricity is a dream for the future; but if this dream is to be realized, we must understand these systems today. As a result, there has been extensive research into the design and economic tradeoffs of utility interconnected photovoltaic applications. The understanding gained in this process has shown that photovoltaic system design can be a very simple and straight-forward endeavor. This paper reviews those past studies and shows how we have reached the present state of system design evolution. The concept of the utility interactive PV system with energy value determined by the utility's avoided cost will be explored. This concept simplifies the screening of potential applications for economic viability, and we will present several rules-of-thumb for this purpose.

  6. Asphaltene based photovoltaic devices

    DOEpatents

    Chianelli, Russell R.; Castillo, Karina; Gupta, Vipin; Qudah, Ali M.; Torres, Brenda; Abujnah, Rajib E.

    2016-03-22

    Photovoltaic devices and methods of making the same, are disclosed herein. The cell comprises a photovoltaic device that comprises a first electrically conductive layer comprising a photo-sensitized electrode; at least one photoelectrochemical layer comprising metal-oxide particles, an electrolyte solution comprising at least one asphaltene fraction, wherein the metal-oxide particles are optionally dispersed in a surfactant; and a second electrically conductive layer comprising a counter-electrode, wherein the second electrically conductive layer comprises one or more conductive elements comprising carbon, graphite, soot, carbon allotropes or any combinations thereof.

  7. High efficiency photovoltaic device

    DOEpatents

    Guha, Subhendu; Yang, Chi C.; Xu, Xi Xiang

    1999-11-02

    An N-I-P type photovoltaic device includes a multi-layered body of N-doped semiconductor material which has an amorphous, N doped layer in contact with the amorphous body of intrinsic semiconductor material, and a microcrystalline, N doped layer overlying the amorphous, N doped material. A tandem device comprising stacked N-I-P cells may further include a second amorphous, N doped layer interposed between the microcrystalline, N doped layer and a microcrystalline P doped layer. Photovoltaic devices thus configured manifest improved performance, particularly when configured as tandem devices.

  8. The DOE photovoltaics program

    NASA Technical Reports Server (NTRS)

    Ferber, R. R.

    1983-01-01

    The considered program of the U.S. Department of Energy (DOE) has the objective to provide federal support for research and development work related to photovoltaics. According to definitions of policy in 1981, a strong emphasis is to be placed on long-term, high-risk research and development that industry could not reasonably be expected to perform using their own funds. Attention is given to the program structure, the photovoltaics program management organization, the advanced research and development subprogram, the collector research and development subprogram, flat-plate collectors, concentrator collectors, and the systems research and technology subprogram.

  9. Photovoltaic device and method

    SciTech Connect

    Nath, P.; Barnard, T.J.; Crea, D.

    1986-05-20

    A photovoltaic device is described comprising: an electrically conductive substrate layer; a semiconductor body deposited upon the substrate layer; a transparent conductive layer over at least a portion of the semiconductor body for facilitating collection of electrical current produced by the photovoltaic device; and a bus-grid structure, in contact with the conductive layer, the bus-grid structure comprising a current collecting portion comprising grid fingers and a current carrying portion comprising a busbar structure for carrying current collected by the current collecting portion, the entirety of the current carrying portion which overlies the semiconductor body being electrically insulated from the semiconductor body by a layer of solid material.

  10. Concentrating photovoltaic solar panel

    SciTech Connect

    Cashion, Steven A; Bowser, Michael R; Farrelly, Mark B; Hines, Braden E; Holmes, Howard C; Johnson, Jr., Richard L; Russell, Richard J; Turk, Michael F

    2014-04-15

    The present invention relates to photovoltaic power systems, photovoltaic concentrator modules, and related methods. In particular, the present invention features concentrator modules having interior points of attachment for an articulating mechanism and/or an articulating mechanism that has a unique arrangement of chassis members so as to isolate bending, etc. from being transferred among the chassis members. The present invention also features adjustable solar panel mounting features and/or mounting features with two or more degrees of freedom. The present invention also features a mechanical fastener for secondary optics in a concentrator module.

  11. Photovoltaic effect in Bi{sub 2}TeO{sub 5} photorefractive crystal

    SciTech Connect

    Oliveira, Ivan de Capovilla, Danilo Augusto

    2015-10-12

    We report on the presence of a strong photovoltaic effect on nominally undoped photorefractive Bi{sub 2}TeO{sub 5} crystals and estimated their Glass photovoltaic constant and photovoltaic field for λ = 532 nm illumination. We directly measured the photovoltaic-based photocurrent in this material under λ = 532 nm wavelength laser light illumination and compared its behavior with that of a well known photovoltaic Fe-doped Lithium Niobate crystal. We also show the photovoltaic current to strongly depend on the polarization direction of light. Holographic diffraction efficiency oscillation during recording and the behavior of fringe-locked running holograms in self-stabilized experiments are also demonstrated here as additional indirect proofs of the photovoltaic nature of this material.

  12. Domestic Communication Satellites

    ERIC Educational Resources Information Center

    Horowitz, Andrew

    1974-01-01

    A discussion of the Federal Communications Commission's new policy on domestic satellites in light of our 1) military and economic history; 2) corporate interests; 3) citizen surveillance; and 4) media control. (HB)

  13. Flexible, rollable photovoltaic cell module

    SciTech Connect

    Cull, C.R.; Hartman, R.A.; Koch, P.E.

    1986-03-04

    A photovoltaic module is described consisting of: busbar means; individual photovoltaic cell strips, each cell strip having an electrically conductive substrate layer, a semiconductor body deposited on the substrate layer, and a transparent electrically conductive layer deposited on the semiconductor body, the transparent electrically conductive layer being selectively sectioned to define electrically distinct photovoltaic cells carried by the cell strip; grid means deposited on the transparent electrically conductive layer of each of the photovoltaic cell; continuous electrically conductive filament means alternately and repetitively connected, at contact points, to the electrically conductive substrate layer of one photovoltaic cell strip and to the grid means of another photovoltaic cell strip; wherein the filament means is connected medially of the lateral edges of the respective cell strips; and means for connecting the transparent electrically conductive layer of one photovoltaic cell strip to the busbar means.

  14. Multiple gap photovoltaic device

    DOEpatents

    Dalal, Vikram L.

    1981-01-01

    A multiple gap photovoltaic device having a transparent electrical contact adjacent a first cell which in turn is adjacent a second cell on an opaque electrical contact, includes utilizing an amorphous semiconductor as the first cell and a crystalline semiconductor as the second cell.

  15. Photovoltaics in Japan

    NASA Technical Reports Server (NTRS)

    Shimada, K.

    1985-01-01

    Report surveys status of research and development on photovoltaics in Japan. Report based on literature searches, private communications, and visits by author to Japanese facilities. Included in survey are Sunshine Project, national program to develop energy sources; industrial development at private firms; and work at academic institutions.

  16. BMDO photovoltaics program overview

    NASA Technical Reports Server (NTRS)

    Caveny, Leonard H.; Allen, Douglas M.

    1994-01-01

    This is an overview of the Ballistic Missile Defense Organization (BMDO) Photovoltaic Program. Areas discussed are: (1) BMDO advanced Solar Array program; (2) Brilliant Eyes type satellites; (3) Electric propulsion; (4) Contractor Solar arrays; (5) Iofee Concentrator and Cell development; (6) Entech linear mini-dome concentrator; and (7) Flight test update/plans.

  17. Photovoltaic radiation detector element

    DOEpatents

    Agouridis, Dimitrios C.

    1983-01-01

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein the edge of which closely approaches but is spaced from the current collector strips.

  18. Photovoltaics reading list

    SciTech Connect

    Not Available

    1984-01-01

    The articles, conference papers, monographs and technical reports cited here are meant to provide a basic introduction to photovoltaics, its research, economics, and technology development. In addition to specific articles and books, several directories, bibliographies, journals, and magazines are suggested as additional sources of information.

  19. Photovoltaic radiation detector element

    DOEpatents

    Agouridis, D.C.

    1980-12-17

    A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein in the edge of which closely approaches but is spaced from the current collector strips.

  20. Formed photovoltaic module busbars

    DOEpatents

    Rose, Douglas; Daroczi, Shan; Phu, Thomas

    2015-11-10

    A cell connection piece for a photovoltaic module is disclosed herein. The cell connection piece includes an interconnect bus, a plurality of bus tabs unitarily formed with the interconnect bus, and a terminal bus coupled with the interconnect bus. The plurality of bus tabs extend from the interconnect bus. The terminal bus includes a non-linear portion.

  1. Flexible photovoltaic device

    SciTech Connect

    Berman, E.

    1989-03-28

    A photovoltaic device is described comprising a transparent substrate, a transparent conductive layer adjacent to the transparent substrate, a TFS layer adjacent to the transparent conductive layer, and a conductive layer adjacent to the TFS layer, the transparent substrate being a tetrafluoroethyleneperfluoroalkooxy resin in the form of a flexible film.

  2. Thin film photovoltaic cell

    DOEpatents

    Meakin, John D.; Bragagnolo, Julio

    1982-01-01

    A thin film photovoltaic cell having a transparent electrical contact and an opaque electrical contact with a pair of semiconductors therebetween includes utilizing one of the electrical contacts as a substrate and wherein the inner surface thereof is modified by microroughening while being macro-planar.

  3. Photovoltaic system criteria documents. Volume 2: Quality assurance criteria for photovoltaic applications

    NASA Technical Reports Server (NTRS)

    Koenig, John C.; Billitti, Joseph W.; Tallon, John M.

    1979-01-01

    Quality assurance criteria are described for manufacturers and installers of solar photovoltaic tests and applications. Quality oriented activities are outlined to be pursued by the contractor/subcontractor to assure the physical and operational quality of equipment produced is included. In the broad sense, guidelines are provided for establishing a QA organization if none exists. Mainly, criteria is provided to be considered in any PV quality assurance plan selected as appropriate by the responsible Field Center. A framework is established for a systematic approach to ensure that photovoltaic tests and applications are constructed in a timely and cost effective manner.

  4. Qualification testing of flat-plate photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Hoffman, A. R.; Griffith, J. S.; Ross, R. G., Jr.

    1982-01-01

    The placement of photovoltaic modules in various applications, in climates and locations throughout the world, results in different degrees and combinations of environmental and electrical stress. Early detection of module reliability deficiencies via laboratory testing is necessary for achieving long, satisfactory field service. This overview paper describes qualification testing techniques being used in the US Department of Energy's flat-plate terrestrial photovoltaic development program in terms of their significance, rationale for specified levels and durations, and test results.

  5. Environmental and Economic Performance of Commercial-scale Solar Photovoltaic Systems: A Field Study of Complex Energy Systems at the Desert Research Institute (DRI)

    NASA Astrophysics Data System (ADS)

    Liu, X.

    2014-12-01

    Solar photovoltaic (PV) systems are being aggressively deployed at residential, commercial, and utility scales to complement power generation from conventional sources. This is motivated both by the desire to reduce carbon footprints and by policy-driven financial incentives. Although several life cycle analyses (LCA) have investigated environmental impacts and energy payback times of solar PV systems, most results are based on hypothetical systems rather than actual, deployed systems that can provide measured performance data. Over the past five years, Desert Research Institute (DRI) in Nevada has installed eight solar PV systems of scales from 3 to 1000 kW, the sum of which supply approximately 40% of the total power use at DRI's Reno and Las Vegas campuses. The goal of this work is to explore greenhouse gas (GHG) impacts and examine the economic performance of DRI's PV systems by developing and applying a comprehensive LCA and techno-economic (TEA) model. This model is built using data appropriate for each type of panel used in the DRI systems. Power output is modeled using the National Renewable Energy Laboratory (NREL) model PVWatts. The performance of PVWatts is verified by the actual measurements from DRI's PV systems. Several environmental and economic metrics are quantified for the DRI systems, including life cycle GHG emissions and energy return. GHG results are compared with Nevada grid-based electricity. Initial results indicate that DRI's solar-derived electricity offers clear GHG benefits compared to conventional grid electricity. DRI's eight systems have GHG intensity values of 29-56 gCO2e/kWh, as compared to the GHG intensity of 212 gCO2e/kWh of national average grid power. The major source of impacts (82-92% of the total) is the upstream life cycle burden of manufacturing PV panels, which are made of either mono-crystalline or multi-crystalline silicon. Given the same type of PV panel, GHG intensity decreases as the scale of the system increases

  6. High voltage with Si series photovoltaics.

    SciTech Connect

    Hsia, Alex; Bennett, Reid Stuart; Patel, Rupal K.; Nasby, Robert D.; Stein, David J.

    2006-02-01

    A monolithic crystalline Si photovoltaic device, developing a potential of 2,120 Volts, has been demonstrated. The monolithic device consists of 3600 small photovoltaic cells connected in series and fabricated using standard CMOS processing on SOI wafers. The SOI wafers with trenches etched to the buried oxide (BOX) depth are used for cell isolation. The photovoltaic cell is a Si pn junction device with the n surface region forming the front surface diffused region upon which light impinges. Contact is formed to the deeper diffused region at the cell edge. The p+ deep-diffused region forms the contact to the p-type base region. Base regions were 5 or 10 {micro}m thick. Series connection of individual cells is accomplished using standard CMOS interconnects. This allows for the voltage to range from approximately 0.5 Volts for a single cell to above a thousand volts for strings of thousands of cells. The current is determined by cell area. The voltage is limited by dielectric breakdown. Each cell is isolated from the adjacent cells through dielectric-filled trench isolation, the substrate through the SOI buried oxide, and the metal wiring by the deposited pre-metal dielectric. If any of these dielectrics fail (whether due to high electric fields or inherent defects), the photovoltaic device will not produce the desired potential. We have used ultra-thick buried oxide SOI and several novel processes, including an oxynitride trench fill process, to avoid dielectric breakdown.

  7. Do experiments with captive non-domesticated animals make sense without population field studies? A case study with blue tits' breeding time

    PubMed Central

    Lambrechts, M. M.; Perret, P.; Maistre, M.; Blondel, J.

    1999-01-01

    A complete understanding of the spatio-temporal variation in phenotypic traits in natural populations requires a combination long-term field studies with experiments using captive animals. Field studies allow the formulation of realistic hypotheses, but have the disadvantage that they do not allow the complete control of many potential confounding variables. Studies with captive animals allow tests of hypotheses that cannot be examined in the field, but have the disadvantage that artificial environments may provoke abnormal behaviour. Long-term studies that follow simultaneously captive and wild bird populations are rare. In a study lasting several years, we show here the unexpected patterns that two populations with a similar breeding time in the wild have non-overlapping breeding times in outdoor aviaries, and that two wild populations separated by a short geographical distance show differences in the expression of natural behaviour in captivity. The experimental design used is exceptional in the sense that the captive populations were held at similar latitudes and altitudes as the wild populations. Our case study shows that studies with captive animals can lead to wrong conclusions if they are carried out without population field studies, and without knowledge of the natural habits and habitats of the species involved. To examine the reliability of experiments with captive animals, comparisons with findings from population field studies are essential.

  8. Design and fabrication of a photovoltaic power system for the Papago Indian village of Schuchuli (Gunsight), Arizona

    NASA Technical Reports Server (NTRS)

    Bifano, W. J.; Ratajczak, A. F.; Ice, W. J.

    1978-01-01

    A stand alone photovoltaic power system for installation in the Papago Indian village of Schuchuli is being designed and fabricated to provide electricity for village water pumping and basic domestic needs. The system will consist of a 3.5 kW (peak) photovoltaic array; controls, instrumentations, and storage batteries located in an electrical equipment building and a 120 volt dc village distribution network. The system will power a 2 HP dc electric motor.

  9. Tests Of Amorphous-Silicon Photovoltaic Modules

    NASA Technical Reports Server (NTRS)

    Ross, Ronald G., Jr.

    1988-01-01

    Progress in identification of strengths and weaknesses of amorphous-silicon technology detailed. Report describes achievements in testing reliability of solar-power modules made of amorphous-silicon photovoltaic cells. Based on investigation of modules made by U.S. manufacturers. Modules subjected to field tests, to accelerated-aging tests in laboratory, and to standard sequence of qualification tests developed for modules of crystalline-silicon cells.

  10. Cost-effective applications of photovoltaics

    SciTech Connect

    Thornton, J.P.

    1996-05-01

    When photovoltaic (PV) cells were first developed at Bell Laboratories in the mid-1950s, their inventors envisioned widespread terrestrial use. However, PV cells were rapidly adopted for space applications, not only because of their reliability, but because they were generally the most cost- effective power sources for satellites in spite of their high cost. Concern over oil supply and price during the 1970s once again turned people`s thoughts toward the use of PV cells and other renewable energy technologies to help meet the nation`s energy demands. A partnership was developed between the federal government and private industry to drive the cost of PV technologies down to where they could compete in commercial markets. This partnership, which continues today, has been highly successful in achieving its goal. Today`s photovoltaic modules-more efficient and reliable than ever-have dropped to about 1/100th of their 1972 prices. From $500 or more per peak watt in those early days, module prices have dropped to about $5 per peak watt. Figure 1 illustrates the expansion of PV into commercial 2 effective markets as cost (and price) decreases. Once cost only in space, military, or consumer (primarily calculators and watches) applications, PV has now penetrated into both international and domestic markets. Currently cost-effective domestic uses, which are the primary subject of this paper, include applications in the residential, municipal, remote, and utility market sectors. The price of an installed PV system now ranges from $7 per watt to as high as $15 or $20 per watt, depending on factors such as the quantity purchased, size of the unit, amount of storage, and whether output is a.c. or d.c. This translates to a life-cycle energy cost of about 25 cents to 40 cents per kilowatt hour (kWh). Even at these seemingly high prices, PV technologies are gaining significant penetration into many U.S. markets.

  11. Liquid Crystal Cells Based on Photovoltaic Substrates

    NASA Astrophysics Data System (ADS)

    Lucchetti, L.; Kushnir, K.; Zaltron, A.; Simoni, F.

    2016-02-01

    Liquid crystal cells with LiNbO3:Fe crystals as substrates, are described. The photovoltaic field generated by the substrates is able to reorient the liquid crystal director thus giving rise to a phase shift on the light propagating through the cell, as in liquid crystal light valves. The process does not require the application of an external electric field, thus being potentially useful for applications requiring a high degree of compactness. An efficient optical switch with a high transmission contrast, based on the described optically-induced electric field, is also proposed.

  12. Photovoltaic module and interlocked stack of photovoltaic modules

    DOEpatents

    Wares, Brian S.

    2012-09-04

    One embodiment relates to an arrangement of photovoltaic modules configured for transportation. The arrangement includes a plurality of photovoltaic modules, each photovoltaic module including a frame having at least a top member and a bottom member. A plurality of alignment features are included on the top member of each frame, and a plurality of alignment features are included on the bottom member of each frame. Adjacent photovoltaic modules are interlocked by the alignment features on the top member of a lower module fitting together with the alignment features on the bottom member of an upper module. Other embodiments, features and aspects are also disclosed.

  13. Superstructure high efficiency photovoltaics

    NASA Technical Reports Server (NTRS)

    Wagner, M.; So, L. C.; Leburton, J. P.

    1987-01-01

    A novel class of photovoltaic cascade structures is introduced which features multijunction upper subcells. These superstructure high efficiency photovoltaics (SHEP's) exhibit enhanced upper subcell spectral response because of the additional junctions which serve to reduce bulk recombination losses by decreasing the mean collection distance for photogenerated minority carriers. Two possible electrical configurations were studied and compared: a three-terminal scheme that allows both subcells to be operated at their individual maximum power points and a two-terminal configuration with an intercell ohmic contact for series interconnection. The three-terminal devices were found to be superior both in terms of beginning-of-life expectancy and radiation tolerance. Realistic simulations of three-terminal AlGaAs/GaAs SHEP's show that one sun AMO efficiencies in excess of 26 percent are possible.

  14. Temperature compensated photovoltaic array

    DOEpatents

    Mosher, Dan Michael

    1997-11-18

    A temperature compensated photovoltaic module (20) comprised of a series of solar cells (22) having a thermally activated switch (24) connected in parallel with several of the cells (22). The photovoltaic module (20) is adapted to charge conventional batteries having a temperature coefficient (TC) differing from the temperature coefficient (TC) of the module (20). The calibration temperatures of the switches (24) are chosen whereby the colder the ambient temperature for the module (20), the more switches that are on and form a closed circuit to short the associated solar cells (22). By shorting some of the solar cells (22) as the ambient temperature decreases, the battery being charged by the module (20) is not excessively overcharged at lower temperatures. PV module (20) is an integrated solution that is reliable and inexpensive.

  15. Temperature compensated photovoltaic array

    DOEpatents

    Mosher, D.M.

    1997-11-18

    A temperature compensated photovoltaic module comprises a series of solar cells having a thermally activated switch connected in parallel with several of the cells. The photovoltaic module is adapted to charge conventional batteries having a temperature coefficient differing from the temperature coefficient of the module. The calibration temperatures of the switches are chosen whereby the colder the ambient temperature for the module, the more switches that are on and form a closed circuit to short the associated solar cells. By shorting some of the solar cells as the ambient temperature decreases, the battery being charged by the module is not excessively overcharged at lower temperatures. PV module is an integrated solution that is reliable and inexpensive. 2 figs.

  16. Photovoltaic power generation

    NASA Astrophysics Data System (ADS)

    Schwartz, Richard J.

    1993-03-01

    The wide acceptance and utilization of the photovoltaic generation of electrical power depends on our ability to reduce the cost of photovoltaic systems. This, in turn, largely hinges on our ability to decrease the cost of production of solar cells and panels while at the same time increasing their conversion efficiency. A short tutorial on solar cells is followed by a discussion of the types of solar cells that are presently being investigated for cost reduction and efficiency improvement. Many types of cells are under investigation as are a wide range of materials. Impressive efficiency improvements have been achieved for many types of cells that are potentially low cost in large-volume production.

  17. Inverted organic photovoltaic cells.

    PubMed

    Wang, Kai; Liu, Chang; Meng, Tianyu; Yi, Chao; Gong, Xiong

    2016-05-21

    The advance in lifestyle, modern industrialization and future technological revolution are always at high expense of energy consumption. Unfortunately, there exist serious issues such as limited storage, high cost and toxic contamination in conventional fossil fuel energy sources. Instead, solar energy represents a renewable, economic and green alternative in the future energy market. Among the photovoltaic technologies, organic photovoltaics (OPVs) demonstrate a cheap, flexible, clean and easy-processing way to convert solar energy into electricity. However, OPVs with a conventional device structure are still far away from industrialization mainly because of their short lifetime and the energy-intensive deposition of top metal electrode. To address the stability and cost issue simultaneously, an inverted device structure has been introduced into OPVs, bridging laboratory research with practical application. In this review, recent progress in device structures, working mechanisms, functions and advances of each component layer as well their correlations with the efficiency and stability of inverted OPVs are reviewed and illustrated. PMID:27087582

  18. Development of photovoltaic array and module safety requirements

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Safety requirements for photovoltaic module and panel designs and configurations likely to be used in residential, intermediate, and large-scale applications were identified and developed. The National Electrical Code and Building Codes were reviewed with respect to present provisions which may be considered to affect the design of photovoltaic modules. Limited testing, primarily in the roof fire resistance field was conducted. Additional studies and further investigations led to the development of a proposed standard for safety for flat-plate photovoltaic modules and panels. Additional work covered the initial investigation of conceptual approaches and temporary deployment, for concept verification purposes, of a differential dc ground-fault detection circuit suitable as a part of a photovoltaic array safety system.

  19. Iron Chalcogenide Photovoltaic Absorbers

    SciTech Connect

    Yu, Liping; Lany, Stephan; Kykyneshi, Robert; Jieratum, Vorranutch; Ravichandran, Ram; Pelatt, Brian; Altschul, Emmeline; Platt, Heather A. S.; Wager, John F.; Keszler, Douglas A.; Zunger, Alex

    2011-08-10

    An integrated computational and experimental study of FeS₂ pyrite reveals that phase coexistence is an important factor limiting performance as a thin-film solar absorber. This phase coexistence is suppressed with the ternary materials Fe₂SiS₄ and Fe₂GeS₄, which also exhibit higher band gaps than FeS₂. Thus, the ternaries provide a new entry point for development of thin-film absorbers and high-efficiency photovoltaics.

  20. Photovoltaic cell array

    NASA Technical Reports Server (NTRS)

    Eliason, J. T. (Inventor)

    1976-01-01

    A photovoltaic cell array consisting of parallel columns of silicon filaments is described. Each fiber is doped to produce an inner region of one polarity type and an outer region of an opposite polarity type to thereby form a continuous radial semi conductor junction. Spaced rows of electrical contacts alternately connect to the inner and outer regions to provide a plurality of electrical outputs which may be combined in parallel or in series.

  1. Increased voltage photovoltaic cell

    NASA Technical Reports Server (NTRS)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  2. Photovoltaic panel support assembly

    SciTech Connect

    Barker, J.M.; Underwood, J.C.; Shingleton, J.

    1993-07-20

    A solar energy electrical power source is described comprising in combination at least two flat photovoltaic panels disposed side-by-side in co-planar relation with one another, a pivot shaft extending transversely across the panels, at least two supports spaced apart lengthwise of the pivot shaft, means for connecting the pivot shaft to the at least two supports, attachment means for connecting the at least two panels to the pivot shaft so that the panels can pivot about the longitudinal axis of the shaft, coupling means mechanically coupling all of the panels together so as to form a unified flat array, and selectively operable drive means for mechanically pivoting the unified flat array about the axis; wherein each of the flat photovoltaic panels comprises at least two modules each comprising a plurality of electrically interconnected photovoltaic cells, the at least two modules being aligned along a line extending at a right angle to the pivot shaft, and the coupling means comprises (a) an elongate member extending parallel to and spaced from the pivot shaft and (b) means for attaching the elongate member to the panels; and further wherein each flat photovoltaic panel comprises a unitary frame consisting of a pair of end frame members extending parallel to the pivot shaft, a pair of side frame members extending between and connected to the end frame members, and a pair of spaced apart cross frame members, with one of the two modules being embraced by and secured to the side frame members and a first one of each of the end and cross frame members, and the other of the two modules being embraced by and secured to the side frame members and the second one of each of the end and cross frame members, whereby the gap created by the spaced apart cross frame members allow air to pass between them in order to reduce the sail effect when the solar array is subjected to buffeting winds.

  3. Photovoltaic-thermal collectors

    DOEpatents

    Cox, III, Charles H.

    1984-04-24

    A photovoltaic-thermal solar cell including a semiconductor body having antireflective top and bottom surfaces and coated on each said surface with a patterned electrode covering less than 10% of the surface area. A thermal-absorbing surface is spaced apart from the bottom surface of the semiconductor and a heat-exchange fluid is passed between the bottom surface and the heat-absorbing surface.

  4. Advances in photovoltaic technology

    NASA Technical Reports Server (NTRS)

    Landis, G. A.; Bailey, S. G.

    1992-01-01

    The advances in solar cell efficiency, radiation tolerance, and cost in the last 10 years are presented. The potential performance of thin-film solar cells in space is examined, and the cost and the historical trends in production capability of the photovoltaics industry are considered with respect to the needs of satellite solar power systems. Attention is given to single-crystal cells, concentrator and cascade cells, and thin-film solar cells.

  5. Photovoltaics and the Environment

    SciTech Connect

    Fthenakis, Vasilis

    2005-09-21

    Over the past five years, solar energy usage has grown by about 43 percent a year, giving rise to a billion-dollar industry in photovoltaics (PV) or getting electricity from light. The word photovoltaics combines the Greek phos, or light, with the “volt” of electricity. PV technologies have distinct environmental advantages over conventional power technologies, such as: no noise, no emissions, no need for fuel and power lines. Compared to burning coal, a gigawatt-hour of PV-generated electricity would prevent the release of about 1,000 tons of carbon dioxide, eight of sulfur dioxide, four of nitrogen oxides, and 0.4 tons of particulates. However, manufacturing the solar cells that transform light to electricity requires the use of some toxic and flammable substances. Addressing the environmental, health, and safety concerns of the PV industry to minimize risk while ensuring economic viability and public support is the work of the National Photovoltaic Environmental Health, & Safety Assistance Center at BNL.

  6. Photovoltaic self-assembly.

    SciTech Connect

    Lavin, Judith; Kemp, Richard Alan; Stewart, Constantine A.

    2010-10-01

    This late-start LDRD was focused on the application of chemical principles of self-assembly on the ordering and placement of photovoltaic cells in a module. The drive for this chemical-based self-assembly stems from the escalating prices in the 'pick-and-place' technology currently used in the MEMS industries as the size of chips decreases. The chemical self-assembly principles are well-known on a molecular scale in other material science systems but to date had not been applied to the assembly of cells in a photovoltaic array or module. We explored several types of chemical-based self-assembly techniques, including gold-thiol interactions, liquid polymer binding, and hydrophobic-hydrophilic interactions designed to array both Si and GaAs PV chips onto a substrate. Additional research was focused on the modification of PV cells in an effort to gain control over the facial directionality of the cells in a solvent-based environment. Despite being a small footprint research project worked on for only a short time, the technical results and scientific accomplishments were significant and could prove to be enabling technology in the disruptive advancement of the microelectronic photovoltaics industry.

  7. Quo Vadis photovoltaics 2011

    NASA Astrophysics Data System (ADS)

    Jäger-Waldau, A.

    2011-10-01

    Since more than 10 years photovoltaics is one of the most dynamic industries with growth rates well beyond 40% per annum. This growth is driven not only by the progress in materials knowledge and processing technology, but also by market introduction programmes in many countries around the world. Despite the negative impacts on the economy by the financial crisis since 2009, photovoltaics is still growing at an extraordinary pace and had in 2010 an extraordinary success, as both production and markets doubled. The open question is what will happen in 2011 and the years after as the situation is dominated by huge manufacturing overcapacities and an increasing unpredictability of policy support. How can the PV industry continue their cost reduction to ensure another 10 to 20 years of sustained and strong growth necessary to make PV to one of the main pillars of a sustainable energy supply in 2030. Despite the fact, that globally the share of electricity from photovoltaic systems is still small, at local level it can be already now above 30% of the demand at certain times of the year. Future research in PV has to provide intelligent solutions not only on the solar cell alone, but also on the module and the system integration level in order to permit a 5 to 10% share of electricity in 2020.

  8. Photovoltaics and the automobile

    SciTech Connect

    Young, W.R. Jr.

    1994-12-31

    For years people have been in love with the automobile. Some people just enjoy using the automobile as transportation while others also enjoy the workings and operation of this fascinating machine. The automobile is not without problems of pollution and energy consumption. These problems are changing its design and construction. New clean energy sources are being analyzed and applied to power the modern automobile. A space age energy source now being considered by some and used by others to power the automobile is photovoltaics. Photovoltaics (PV) is the direct conversion of sunlight to electricity. There are a number of devices in the modern car that are electrically powered. PV could provide a clean endless supply of electricity for air conditioning, radios and other electrical components of a car. Most people have never heard of photovoltaics (PV). There has been a great deal of research in PV among energy experts. The automobile is known the world over in both use and operation. The author describes how the merging of these two technologies will benefit mankind and without damaging the environment. 12 refs.

  9. Photocurrent of Photovoltaic Cells

    NASA Astrophysics Data System (ADS)

    Peeler, Seth; McIntyre, Max; Cossel, Raquel; Bowser, Chris; Tzolov, Marian

    Photovoltaic cells can be used to harness clean, renewable energy from light. Examined in this project were photovoltaic cells based on a bulk heterojunction between PCPDTBT and PCBM sandwiched between an ITO anode and an Al cathode. Current-voltage characteristics and impedance spectra for multiple photovoltaic devices were taken under varying DC electrical bias and different level of illumination. This data was interpreted in terms of an equivalent circuit with linear elements, e.g. capacitance, series resistance, and parallel resistance. A physical interpretation of each circuit element will be presented. The spectral response of the devices was characterized by optical transmission and photocurrent spectroscopy using a spectrometer in the spectral range from 300 to 900 nm. The DC measurements confirmed that the devices are electrically rectifying. The AC measurements allowed modeling of the devices as a dielectric between two electrodes with injection current passing through it. The characteristic peaks for both PCBDTBT and PCBM are clearly visible in both the photocurrent and transmission data. The good correlation between the photocurrent and transmission data indicates photocurrent generation due to absorption in both materials constituting the heterojunction.

  10. Analysis methods for photovoltaic applications

    SciTech Connect

    1980-01-01

    Because photovoltaic power systems are being considered for an ever-widening range of applications, it is appropriate for system designers to have knowledge of and access to photovoltaic power systems simulation models and design tools. This brochure gives brief descriptions of a variety of such aids and was compiled after surveying both manufacturers and researchers. Services available through photovoltaic module manufacturers are outlined, and computer codes for systems analysis are briefly described. (WHK)

  11. Utility-scale photovoltaic concentrators

    SciTech Connect

    None, None

    2009-01-18

    The photovoltaics concentrators section of the Renewable Energy Technology Characterizations describes the technical and economic status of this emerging renewable energy option for electricity supply.

  12. Solar photovoltaics for development applications

    SciTech Connect

    Shepperd, L.W.; Richards, E.H.

    1993-08-01

    This document introduces photovoltaic technology to individuals and groups specializing in development activities. Examples of actual installations illustrate the many services supplied by photovoltaic systems in development applications, including water pumping, lighting, health care, refrigeration, communications, and a variety of productive uses. The various aspects of the technology are explored to help potential users evaluate whether photovoltaics can assist them in achieving their organizational goals. Basic system design, financing techniques, and the importance of infrastructure are included, along with additional sources of information and major US photovoltaic system suppliers.

  13. Do photovoltaics have a future

    NASA Technical Reports Server (NTRS)

    Williams, B. F.

    1979-01-01

    There is major concern as to the economic practicality of widespread terrestrial use because of the high cost of the photovoltaic arrays themselves. Based on their high efficiency, photovoltaic collectors should be one of the cheapest forms of energy generators known. Present photovoltaic panels are violating the trend of lower costs with increasing efficiency due to their reliance on expensive materials. A medium technology solution should provide electricity competitive with the existing medium to high technology energy generators such as oil, coal, gas, and nuclear fission thermal plants. Programs to reduce the cost of silicon and develop reliable thin film materials have a realistic chance of producing cost effective photovoltaic panels.

  14. Solid domestic wastes as a renewable resource: European experience

    NASA Astrophysics Data System (ADS)

    Fridland, V. S.; Livshits, I. M.

    2011-01-01

    Ways in which different types of solid domestic wastes, such as wastepaper, crushed glass, plastics and worn-out tires, can be efficiently included into the production, raw-material, and energy balances of the national economy are shown taking Germany and other European countries an example. Methods for recycling these solid domestic wastes and application fields of the obtained products are discussed.

  15. Working with a domestic assessment system to estimate the need of support and care of elderly and disabled persons: results from field studies.

    PubMed

    Hein, Andreas; Steen, Enno-Edzard; Thiel, Andreas; Hülsken-Giesler, Manfred; Wist, Thorben; Helmer, Axel; Frenken, Thomas; Isken, Melvin; Schulze, Gisela C; Remmers, Hartmut

    2014-01-01

    This article describes the results of field studies performed over a period between five months and 24 months. The objectives of these studies were to collect long-term real-life data to evaluate how these data can be mapped to items on standardized assessment tests and which presentation method is most suitable to inform caregivers about critical situations and changes in health or care needs. A Home-monitoring system which uses modern sensor technologies was developed for and used in these field studies. It was installed in living environments of seven people (three who were not in need of care, two in need of care, and two with mental disabilities). The data were generated by sensor data acquisition and questionnaire reporting. Four types of data analysis and representation were evaluated to support caregivers. Results show that sensor data can be used to determine information directly or indirectly, which can be mapped to relevant assessment items and presented with different degrees of granularity. It is also feasible to determine and present additional information of potential interest which cannot be directly mapped to any assessment item. Sensor data can also be displayed in a live view. This live data representation led to a decrease in the caregivers' workload when assessed according to the German version of the Perceived Stress Questionnaire. PMID:25148558

  16. Photovoltaics with Ferroelectrics: Current Status and Beyond.

    PubMed

    Paillard, Charles; Bai, Xiaofei; Infante, Ingrid C; Guennou, Maël; Geneste, Grégory; Alexe, Marin; Kreisel, Jens; Dkhil, Brahim

    2016-07-01

    Ferroelectrics carry a switchable spontaneous electric polarization. This polarization is usually coupled to strain, making ferroelectrics good piezoelectrics. When coupled to magnetism, they become so-called multiferroic systems, a field that has been widely investigated since 2003. While ferroelectrics are birefringent and non-linear optically transparent materials, the coupling of polarization with optical properties has received, since 2009, renewed attention, triggered notably by low-bandgap ferroelectrics suitable for sunlight spectrum absorption and original photovoltaic effects. Consequently, power conversion efficiencies up to 8.1% were recently achieved and values of 19.5% were predicted, making photoferroelectrics promising photovoltaic alternatives. This article aims at providing an up-to-date review on this emerging and rapidly progressing field by highlighting several important issues and parameters, such as the role of domain walls, ways to tune the bandgap, consequences arising from the polarization switchability, and the role of defects and contact electrodes, as well as the downscaling effects. Beyond photovoltaicity, other polarization-related processes are also described, like light-induced deformation (photostriction) or light-assisted chemical reaction (photostriction). It is hoped that this overview will encourage further avenues to be explored and challenged and, as a byproduct, will inspire other research communities in material science, e.g., so-called hybrid halide perovskites. PMID:27135419

  17. Measurement of Global Radiation using Photovoltaic Panels

    NASA Astrophysics Data System (ADS)

    Veroustraete, Frank; Bronders, Jan; Lefevre, Filip; Mensink, Clemens

    2014-05-01

    The Vito Unit - Environmental and Spatial Aspects (RMA) - for many of its models makes use of global solar radiation. From this viewpoint and also from the notion that this variable is seldom measured or available at the local scale and at high multi-temporal frequencies, it can be stated that many models are fed with low quality estimates of global solar radiation at the local to regional scales. A project was initiated called SUNSPIDER with the following objective. To make use of photovoltaic solar panels to measure solar radiation at the highest spatio-temporal resolution, from the local to the regional scales and from minutes to years. To integrate the measured solar fields in different application fields like, plant systems and agriculture, agro-meteorology and hydrology and last but not least solar energy applications. In Belgium about 250.000 PV installations have been built leading to about 6% electric power supply from photovoltaics on a yearly basis. Last year in June, the supply reached a peak of more than 20% of the total power input on the Belgian grid. A database of Belgian residential solar panel sites will be compiled. The database will serve as an input to an inverted PV model to be able to perform radiation calculations specifically for each of the validated panel sites based on minutely logged power data. Data acquisition for these sites will start each time a site is validated and hence imported in the database. Keywords: Photovoltaic Panels; PV modelling; Global Radiation.

  18. Challenging Domestic Violence.

    ERIC Educational Resources Information Center

    Scarlett, Chris

    2002-01-01

    In Britain, a Women's Aid program offers practical support and assistance to abused women. Survivors of domestic abuse can benefit from the opportunity afforded by an objective appraisal of the social context of their personal experiences, facilitated by trained volunteers. (JOW)

  19. Domestic Research at Rand.

    ERIC Educational Resources Information Center

    Rand Corp., Santa Monica, CA.

    This third descriptive inventory of the Rand Corporation's domestic non-military research covers all projects since 1972, as well as its special 1969-1975 program for New York City. For each of over 300 research projects in nine program areas, brief summaries identify the project title and sponsor, beginning and ending dates, person-years of work…

  20. Cogasification of domestic fuels

    SciTech Connect

    Green, A.; Peres, S.; Mullin, J.; Xue, H.

    1995-12-31

    Advanced developments in military aircraft turbine technology have been applied to aeroderivative and large frame combustion turbines. When these advanced turbines are applied to combined cycle systems they result in the highest efficiency electrical generation systems now available. Integrating such a system with a front end coal gasifier is now considered one of the most promising near term Clean Coal Technologies. Gasification of other domestic solid fuels: biomass, MSW and tires could also provide the fuel input to combustion turbines. However, with low oil prices natural gas energy prices are too close to the energy prices of solid fuels to overcome the capital and operating costs of a conventional gasifier. The authors here consider on-site cogasification of domestic fuels to identify feedstock combinations that could be cogasified profitably even when oil prices are low. Coal-natural gas, coal-biomass, biomass-natural gas, coal-MSW are among the promising, domestic combinations. They conclude that cogasification of domestic fuels could serve as a near term clean combustion technology helpful towards trade deficit reduction and achieving global environmental goals.

  1. Domestic Communications Satellites.

    ERIC Educational Resources Information Center

    Network Project Notebook, 1972

    1972-01-01

    The June, 1972 Federal Communications Commission's (FCC) decision allowed an "open skies" policy in regard to domestic communication satellites and raised Liberal opposition to a situation where exclusive and unchecked communications power is now in the hands of private entrepreneurs, primarily the big Defense Department oriented aerospace…

  2. Lithium-doping inverts the nanoscale electric field at the grain boundaries in Cu2ZnSn(S,Se)4 and increases photovoltaic efficiency.

    PubMed

    Xin, H; Vorpahl, S M; Collord, A D; Braly, I L; Uhl, A R; Krueger, B W; Ginger, D S; Hillhouse, H W

    2015-10-01

    Passive grain boundaries (GBs) are essential for polycrystalline solar cells to reach high efficiency. However, the GBs in Cu2ZnSn(S,Se)4 have less favorable defect chemistry compared to CuInGaSe2. Here, using scanning probe microscopy we show that lithium doping of Cu2ZnSn(S,Se)4 changes the polarity of the electric field at the GB such that minority carrier electrons are repelled from the GB. Solar cells with lithium-doping show improved performance and yield a new efficiency record of 11.8% for hydrazine-free solution-processed Cu2ZnSn(S,Se)4. We propose that lithium competes for copper vacancies (forming benign isoelectronic LiCu defects) decreasing the concentration of ZnCu donors and competes for zinc vacancies (forming a LiZn acceptor that is likely shallower than CuZn). Both phenomena may explain the order of magnitude increase in conductivity. Further, the effects of lithium doping reported here establish that extrinsic species are able to alter the nanoscale electric fields near the GBs in Cu2ZnSn(S,Se)4. This will be essential for this low-cost Earth abundant element semiconductor to achieve efficiencies that compete with CuInGaSe2 and CdTe. PMID:26302694

  3. Photovoltaic Performance and Reliability Workshop summary

    NASA Astrophysics Data System (ADS)

    Kroposki, Benjamin

    1997-02-01

    The objective of the Photovoltaic Performance and Reliability Workshop was to provide a forum where the entire photovoltaic (PV) community (manufacturers, researchers, system designers, and customers) could get together and discuss technical issues relating to PV. The workshop included presentations from twenty-five speakers and had more than one hundred attendees. This workshop also included several open sessions in which the audience and speakers could discuss technical subjects in depth. Several major topics were discussed including: PV characterization and measurements, service lifetimes for PV devices, degradation and failure mechanisms for PV devices, standardization of testing procedures, AC module performance and reliability testing, inverter performance and reliability testing, standardization of utility interconnect requirements, experience from field deployed systems, and system certification.

  4. Microsystem enabled photovoltaic modules and systems

    DOEpatents

    Nielson, Gregory N; Sweatt, William C; Okandan, Murat

    2015-05-12

    A microsystem enabled photovoltaic (MEPV) module including: an absorber layer; a fixed optic layer coupled to the absorber layer; a translatable optic layer; a translation stage coupled between the fixed and translatable optic layers; and a motion processor electrically coupled to the translation stage to controls motion of the translatable optic layer relative to the fixed optic layer. The absorber layer includes an array of photovoltaic (PV) elements. The fixed optic layer includes an array of quasi-collimating (QC) micro-optical elements designed and arranged to couple incident radiation from an intermediate image formed by the translatable optic layer into one of the PV elements such that it is quasi-collimated. The translatable optic layer includes an array of focusing micro-optical elements corresponding to the QC micro-optical element array. Each focusing micro-optical element is designed to produce a quasi-telecentric intermediate image from substantially collimated radiation incident within a predetermined field of view.

  5. Natural sunlight accelerated weathering of photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Zerlaut, G. A.; Anderson, T. B.; Arnett, J. C.

    Photovoltaic modules are exposed to the equivalent of ten years of sunlight aging in an accelerated exposure testing and evaluation program, the objective being to determine the long-term durability characteristics of flat plate modules in comparatively short periods of time. The modules are illuminated with concentrated sunlight in a large, sun-tracking, Fresnel-reflecting solar concentrator. The effects of the accelerated exposure are assessed by performing periodic visual inspections and electrical measurements. It is found that field-experienced failure modes are duplicated, that acceleration factors of 6x to 8x are readily attainable, and that the test method is feasible as a predictive tool for photovoltaic module lifetime durability.

  6. Natural sunlight accelerated weathering of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Zerlaut, G. A.; Anderson, T. B.; Arnett, J. C.

    1981-01-01

    Photovoltaic modules are exposed to the equivalent of ten years of sunlight aging in an accelerated exposure testing and evaluation program, the objective being to determine the long-term durability characteristics of flat plate modules in comparatively short periods of time. The modules are illuminated with concentrated sunlight in a large, sun-tracking, Fresnel-reflecting solar concentrator. The effects of the accelerated exposure are assessed by performing periodic visual inspections and electrical measurements. It is found that field-experienced failure modes are duplicated, that acceleration factors of 6x to 8x are readily attainable, and that the test method is feasible as a predictive tool for photovoltaic module lifetime durability.

  7. Modeling of Hydrogenated Amorphous Silicon (a-Si:H) Thin Films Prepared by the Saddle Field Glow Discharge Method for Photovoltaic Applications

    NASA Astrophysics Data System (ADS)

    Sachenko, A. V.; Shkrebtii, A. I.; Gaspari, F.; Kherani, N.; Kazakevitch, A.

    2008-01-01

    We present results of combined theoretical and experimental study of the thin hydrogenated amorphous silicon (a-Si:H) films based solar cells. The films for efficient and inexpensive solar cells were grown by the Saddle Field Glow Discharge Method. An analytical model to optimize photo-conversion efficiency a-Si:H based solar cells with contact grid has been developed. This two-dimensional model allows an optimization of the p+-i-n sandwich in terms of carrier mobilities, layers thickness, doping levels and others. The geometry of the grid fingers that conduct the photo-current to the bus bars and ITO/SiO2 layers has been optimizes as well as the effect of non-zero sun incidence angles. We demonstrate the optimization method to the typical a-Si:H solar cells.

  8. Interim performance criteria for photovoltaic energy systems. [Glossary included

    SciTech Connect

    DeBlasio, R.; Forman, S.; Hogan, S.; Nuss, G.; Post, H.; Ross, R.; Schafft, H.

    1980-12-01

    This document is a response to the Photovoltaic Research, Development, and Demonstration Act of 1978 (P.L. 95-590) which required the generation of performance criteria for photovoltaic energy systems. Since the document is evolutionary and will be updated, the term interim is used. More than 50 experts in the photovoltaic field have contributed in the writing and review of the 179 performance criteria listed in this document. The performance criteria address characteristics of present-day photovoltaic systems that are of interest to manufacturers, government agencies, purchasers, and all others interested in various aspects of photovoltaic system performance and safety. The performance criteria apply to the system as a whole and to its possible subsystems: array, power conditioning, monitor and control, storage, cabling, and power distribution. They are further categorized according to the following performance attributes: electrical, thermal, mechanical/structural, safety, durability/reliability, installation/operation/maintenance, and building/site. Each criterion contains a statement of expected performance (nonprescriptive), a method of evaluation, and a commentary with further information or justification. Over 50 references for background information are also given. A glossary with definitions relevant to photovoltaic systems and a section on test methods are presented in the appendices. Twenty test methods are included to measure performance characteristics of the subsystem elements. These test methods and other parts of the document will be expanded or revised as future experience and needs dictate.

  9. Graphite-based photovoltaic cells

    DOEpatents

    Lagally, Max; Liu, Feng

    2010-12-28

    The present invention uses lithographically patterned graphite stacks as the basic building elements of an efficient and economical photovoltaic cell. The basic design of the graphite-based photovoltaic cells includes a plurality of spatially separated graphite stacks, each comprising a plurality of vertically stacked, semiconducting graphene sheets (carbon nanoribbons) bridging electrically conductive contacts.

  10. Maintenance of photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Hall, M. R.

    1984-08-01

    This publication establishes standard practices for inspection, testing, and maintenance of photovoltaic power systems at Dept. of the Navy installations. The practices and procedures are recommended to ensure reliable operation of the power systems. The manual covers photovoltaic-array, battery, voltage-regulator, inverter, and wiring subsystems. In addition, this manual provides a troubleshooting guide and self-study questions and answers.

  11. Maintenance of photovoltaic power systems

    SciTech Connect

    Hall, M.R.

    1984-08-01

    This publication establishes standard practices for inspection, testing, and maintenance of photovoltaic power systems at Department of the Navy installations. The practices and procedures are recommended to ensure reliable operation of the power systems. The manual covers photovoltaic-array, battery, voltage-regulator, inverter, and wiring subsystems. In addition, this manual provides a troubleshooting guide and self-study questions and answers.

  12. Photovoltaic conversion of laser energy

    NASA Technical Reports Server (NTRS)

    Stirn, R. J.

    1976-01-01

    The Schottky barrier photovoltaic converter is suggested as an alternative to the p/n junction photovoltaic devices for the conversion of laser energy to electrical energy. The structure, current, output, and voltage output of the Schottky device are summarized. The more advanced concepts of the multilayer Schottky barrier cell and the AMOS solar cell are briefly considered.

  13. 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)

  14. Design and development of sustainable remediation process for mitigation of fluoride contamination in ground water and field application for domestic use.

    PubMed

    Gwala, Poonam; Andey, Subhash; Nagarnaik, Pranav; Ghosh, Sarika Pimpalkar; Pal, Prashant; Deshmukh, Prashant; Labhasetwar, Pawan

    2014-08-01

    Decentralised household chemo defluoridation unit (CDU) was developed and designed based on a combination of coagulation and sorption processes. Chemo-defluoridation process was optimised to reduce use of chemicals and increase acceptability among beneficiaries without affecting palatability of water. Chemical dose optimization undertaken in the laboratory using jar test revealed the optimum calcium salt to initial fluoride ratio of 60 for fluoride removal. Performance of CDU was evaluated in the laboratory for removal efficiency, water quality parameters, filter bed cleaning cycle and desorption of fluoride. CDU evaluation in the laboratory with spiked water (5 mg/L) and field water (~4.2 mg/L) revealed treated water fluoride concentration of less than 1mg/L. Seventy five CDUs were installed in households at Sakhara Village, Yavatmal District in Maharashtra State of India. Monthly monitoring of CDUs for one year indicated reduction of the raw water fluoride concentration from around 4 mg/L to less than 1mg/L. Post implementation survey after regular consumption of treated drinking water by the users for one year indicated user satisfaction and technological sustainability. PMID:24560102

  15. Genetic testing in domestic cats

    PubMed Central

    Lyons, Leslie A.

    2012-01-01

    Varieties of genetic tests are currently available for the domestic cat that support veterinary health care, breed management, species identification, and forensic investigations. Approximately thirty-five genes contain over fifty mutations that cause feline health problems or alterations in the cat’s appearance. Specific genes, such as sweet and drug receptors, have been knocked-out of Felidae during evolution and can be used along with mtDNA markers for species identification. Both STR and SNP panels differentiate cat race, breed, and individual identity, as well as gender-specific markers to determine sex of an individual. Cat genetic tests are common offerings for commercial laboratories, allowing both the veterinary clinician and the private owner to obtain DNA test results. This article will review the genetic tests for the domestic cat, and their various applications in different fields of science. Highlighted are genetic tests specific to the individual cat, which are a part of the cat’s genome. PMID:22546621

  16. Photovoltaic panel clamp

    DOEpatents

    Mittan, Margaret Birmingham; Miros, Robert H. J.; Brown, Malcolm P.; Stancel, Robert

    2012-06-05

    A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

  17. Photovoltaic panel clamp

    DOEpatents

    Brown, Malcolm P.; Mittan, Margaret Birmingham; Miros, Robert H. J.; Stancel, Robert

    2013-03-19

    A photovoltaic panel clamp includes an upper and lower section. The interface between the assembled clamp halves and the module edge is filled by a flexible gasket material, such as EPDM rubber. The gasket preferably has small, finger like protrusions that allow for easy insertion onto the module edge while being reversed makes it more difficult to remove them from the module once installed. The clamp includes mounting posts or an integral axle to engage a bracket. The clamp also may include a locking tongue to secure the clamp to a bracket.

  18. Thin film photovoltaic device

    DOEpatents

    Catalano, A.W.; Bhushan, M.

    1982-08-03

    A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids. 5 figs.

  19. Characterization of Photovoltaic Concentrators

    SciTech Connect

    Kiehl, J.; Emery, E.

    2005-01-01

    This paper will describe the resources at the National Renewable Energy Laboratory (NREL) for performing characterization of photovoltaic (PV) materials designed for operation under concentrated light. NREL has the capability to measure devices ranging from very small, unencapsulated research cells to reasonably sized, environmentally protected modules. Data gathering and interpretation are also ongoing areas of revision and improvement. The main goal of the current research is to reduce the measurement uncertainty to the lowest practical value. At present, the state of the art is limited at a ?5% level in measuring efficiency accurately.

  20. Europe's space photovoltaics programme

    NASA Technical Reports Server (NTRS)

    Bogus, Klaus P.

    1994-01-01

    The current space PV (photovoltaic) technology development program of ESA is described. The program is closely coupled to the European space mission scenario for the next 10 year period and has as its main objective to make the most effective use of the limited resources available for technology in the present economical climate. This requires a well-balanced approach between concentration on very few options and keeping the competition alive if more than one promising technology exists. The paper describes ESA's main activities in the areas of solar array technology, solar cell technology, solar cell assembly technology, and special test and verification activities including the in-orbit demonstration of new technologies.

  1. Photovoltaic system reliability

    SciTech Connect

    Maish, A.B.; Atcitty, C.; Greenberg, D.

    1997-10-01

    This paper discusses the reliability of several photovoltaic projects including SMUD`s PV Pioneer project, various projects monitored by Ascension Technology, and the Colorado Parks project. System times-to-failure range from 1 to 16 years, and maintenance costs range from 1 to 16 cents per kilowatt-hour. Factors contributing to the reliability of these systems are discussed, and practices are recommended that can be applied to future projects. This paper also discusses the methodology used to collect and analyze PV system reliability data.

  2. Photovoltaic Degradation Risk: Preprint

    SciTech Connect

    Jordan, D. C.; Kurtz, S. R.

    2012-04-01

    The ability to accurately predict power delivery over the course of time is of vital importance to the growth of the photovoltaic (PV) industry. Important cost drivers include the efficiency with which sunlight is converted into power, how this relationship changes over time, and the uncertainty in this prediction. An accurate quantification of power decline over time, also known as degradation rate, is essential to all stakeholders - utility companies, integrators, investors, and researchers alike. In this paper we use a statistical approach based on historical data to quantify degradation rates, discern trends and quantify risks related to measurement uncertainties, number of measurements and methodologies.

  3. Thin film photovoltaic device

    DOEpatents

    Catalano, Anthony W.; Bhushan, Manjul

    1982-01-01

    A thin film photovoltaic solar cell which utilizes a zinc phosphide semiconductor is of the homojunction type comprising an n-type conductivity region forming an electrical junction with a p-type region, both regions consisting essentially of the same semiconductor material. The n-type region is formed by treating zinc phosphide with an extrinsic dopant such as magnesium. The semiconductor is formed on a multilayer substrate which acts as an opaque contact. Various transparent contacts may be used, including a thin metal film of the same chemical composition as the n-type dopant or conductive oxides or metal grids.

  4. Photovoltaic energy systems

    NASA Astrophysics Data System (ADS)

    1988-02-01

    An overview is provided of the activities within the National Photovoltaics Program. Tasks conducted by the participating national laboratories or under contract by industrial, academic and other research institutions are highlighted. Activities initiated, renewed, or completed during Fiscal Year 1987 are covered. The listing for each activity provides the task title, objectives, approach, status and accomplishments, milestones, major project reports, the name of the contractor and principal investigator, the directing organization, and the contract funding information. Publications for FY86-87 are also listed.

  5. Bracket for photovoltaic modules

    DOEpatents

    Ciasulli, John; Jones, Jason

    2014-06-24

    Brackets for photovoltaic ("PV") modules are described. In one embodiment, a saddle bracket has a mounting surface to support one or more PV modules over a tube, a gusset coupled to the mounting surface, and a mounting feature coupled to the gusset to couple to the tube. The gusset can have a first leg and a second leg extending at an angle relative to the mounting surface. Saddle brackets can be coupled to a torque tube at predetermined locations. PV modules can be coupled to the saddle brackets. The mounting feature can be coupled to the first gusset and configured to stand the one or more PV modules off the tube.

  6. Photovoltaic manufacturing technology

    SciTech Connect

    Wohlgemuth, J.H.; Whitehouse, D.; Wiedeman, S.; Catalano, A.W.; Oswald, R. )

    1991-12-01

    This report identifies steps leading to manufacturing large volumes of low-cost, large-area photovoltaic (PV) modules. Both crystalline silicon and amorphous silicon technologies were studied. Cost reductions for each step were estimated and compared to Solarex Corporation's manufacturing costs. A cost model, a simple version of the SAMICS methodology developed by the Jet Propulsion Laboratory (JPL), projected PV selling prices. Actual costs of materials, labor, product yield, etc., were used in the cost model. The JPL cost model compared potential ways of lowering costs. Solarex identified the most difficult technical challenges that, if overcome, would reduce costs. Preliminary research plans were developed to solve the technical problems. 13 refs.

  7. Photovoltaic Manufacturing Technology

    NASA Astrophysics Data System (ADS)

    Easoz, J. R.; Herlocher, R. H.

    1991-12-01

    This report examines the cost-effective manufacture of dendritic-web-based photovoltaic modules. It explains how process changes can increase production and reduce manufacturing costs. Long-range benefits of these improved processes are also discussed. Problems are identified that could impede increasing production and reducing costs; approaches to solve these problems are presented. These approaches involve web growth throughput, cell efficiency, process yield, silicon use, process control, automation, and module efficiency. Also discussed are the benefits of bifacial module design, unique to the dendritic web process.

  8. Photovoltaic tests and applications project

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The activities and accomplishments of the Photovoltaic Tests and Applications Project during the period April 1976 through June 1977 are summarized. Results of efforts to identify potential near-term photovoltaic applications and users are discussed, including the outcome of an extensive survey of Federal government agencies. The status of application experiments is presented. Various general engineering efforts are reported, including the design and construction of a photovoltaic Systems Test Facility. Efforts to develop a high efficiency 10 kVA self-commutated inverter and controller specifically designed for photovoltaic systems are also discussed. The results of a wide variety of activities in the area of photovoltaic measurements and standards are related. Documents generated by the Project during the reporting period are listed in an Appendix.

  9. Photovoltaic-cell-research priorities

    SciTech Connect

    Bornstein, J.G.; Hien, L.K.; Silberglitt, R.

    1983-09-30

    The current state of research and development on photovoltaic materials and advanced concepts are reviewed, and priority research activities for improved photovoltaic cells in the major individual research areas (i.e., silicon, III-V materials, II-VI materials) are identified. Also noted is the importance of reserving a small but finite portion of photovoltaic research funding for out-of-the-mainstream research. The major features of a research management philosophy aimed at attracting the best available scientific resources and research capabilities to photovoltaic research and development are outlined. The priority research activities in the principal areas of photovoltaic research are then summarized and compared, and the overall conclusions of the assessment are presented. (LEW)

  10. Detection of beta2 and major toxin genes by PCR in Clostridium perfringens field isolates of domestic animals suffering from enteritis or enterotoxaemia.

    PubMed

    Sting, Reinhard

    2009-01-01

    The production of Clostridium (C.) perfringens toxins in the intestine is an important cause of enteritis and enterotoxaemia in livestock. In the present study, the alpha toxin and the genes encoding beta2 and epsilon toxin could be frequently detected by means of phenotypical and PCR examinations in these bacteria. The C. perfringens isolates originated from 1213 field samples taken from diseased or perished livestock located in the north-eastern administrative districts of Baden-Württemberg (Germany) from 2005 to 2008. The beta2 toxin gene of C perfringens was detected in all animal species examined, comprising pigs, the small ruminants sheep and goats, cattle, horses, rabbits, alpacas and lamas, and fallow deer. Among all the animal species included in this study, pigs attracted attention by a high quota of 74.2% (610 of 822) cpb2-positive C. perfringens isolates in comparison to the other animal species tested, revealing a quota of 20.8% (72 of 346). Beta2 toxigenic isolates could be predominantly cultivated from the faeces of young piglets. The beta toxin gene was detected in isolates from piglets and small ruminants only, amounting to 82.5% (33 of 40) in piglets in combination with the cpb2 gene. In this context, cpb2/cpb-positive C. perfringens isolates of piglets could be clearly detected more often in the intestine of perished animals (18 of 158) than in faeces (15 of 629). Furthermore, cpb2-bearing C. perfringens isolates were detected in cattle, horses, rabbits, alpacas and lamas, and fallow deer to a notable degree. The detection of C. perfringens isolates carrying the epsilon toxin gene was restricted to sheep and goats. Of a total of 242 small ruminants that succumbed to sudden death, 71 (29.3%) harboured epsilon toxin-positive C. perfringens isolates in their intestines. These cases clustered seasonally in the second quarter (April, May, and June) of the year. Neither the isolates bearing the beta2 nor beta toxin gene nor those carrying the epsilon