Science.gov

Sample records for advanced photovoltaic systems

  1. Advanced photovoltaic power system technology for lunar base applications

    NASA Technical Reports Server (NTRS)

    Brinker, David J.; Flood, Dennis J.

    1992-01-01

    The development of an advanced photovoltaic power system that would have application for a manned lunar base is currently planned under the Surface Power element of Pathfinder. Significant mass savings over state-of-the-art photovoltaic/battery systems are possible with the use of advanced lightweight solar arrays coupled with regenerative fuel cell storage. The solar blanket, using either ultrathin GaAs or amorphous silicon solar cells, would be integrated with a reduced-g structure. Regenerative fuel cells with high-pressure gas storage in filament-wound tanks are planned for energy storage. An advanced PV/RFC power system is a leading candidate for a manned lunar base as it offers a tremendous weight advantage over state-of-the-art photovoltaic/battery systems and is comparable in mass to other advanced power generation technologies.

  2. Development of an advanced photovoltaic concentrator system for space applications

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F., Jr.; Oneill, Mark J.

    1987-01-01

    Recent studies indicate that significant increases in system performance (increased efficiency and reduced system mass) are possible for high power space based systems by incorporating technological developments with photovoltaic power systems. The Advanced Photovoltaic Concentrator Program is an effort to take advantage of recent advancements in refractive optical elements. By using a domed Fresnel lens concentrator and a prismatic cell cover, to eliminate metallization losses, dramatic reductions in the required area and mass over current space photovoltaic systems are possible. The advanced concentrator concept also has significant advantages when compared to solar dynamic Organic Rankine Cycle power systems in Low Earth Orbit applications where energy storage is required. The program is currently involved in the selection of a material for the optical element that will survive the space environment and a demonstration of the system performance of the panel design.

  3. Advanced photovoltaic power system technology for lunar base applications

    NASA Technical Reports Server (NTRS)

    Brinker, David J.; Flood, Dennis J.

    1988-01-01

    Advanced photovoltaic/electrochemical (batteries or regenerative fuel cells for storage) power system options for a lunar base are discussed and compared. Estimated system masses are compared with those projected for the SP-100 nuclear system. The results of the comparison are quantified in terms of the mass saved in a scenario which assembles the initial base elements in Low Earth Orbit (LEO) and launches from there to the lunar surface. A brief summary is given of advances in photovoltaic/electrochemical power system technologies currently under development in the NASA/OAST program. A description of the planned focussed technology program for surface power in the new Pathfinder initiative is also provided.

  4. Solar photovoltaic systems

    NASA Technical Reports Server (NTRS)

    Forney, R. G.

    1978-01-01

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

  5. Advanced photovoltaic concentrator system low-cost prototype module

    SciTech Connect

    Kaminar, N.R.; McEntee, J.; Curchod, D. )

    1991-09-01

    This report describes the continued development of an extruded lens and the development of a PV receiver, both of which will be used in the Solar Engineering Applications Corporation (SEA) 10X concentrator. These efforts were pare of a pre-Concentrator Initiative Program. The 10X concentrator consists of an inexpensive, extruded linear Fresnel lens which focuses on one-sun cells which are adhesive-bonded to an anodized aluminum heat sink. Module sides are planned to be molded along with the lens and are internally reflective for improved on- and off-track performance. End caps with molded-in bearings complete the module. Ten modules are mounted in a stationary frame for simple, single-axis tracking in the east-west direction. This configuration an array, is shipped completely assembled and requires only setting on a reasonably flat surface, installing 4 fasteners, and hooking up the wires. Development of the 10-inch wide extruded lens involved one new extrusion die and a series of modifications to this die. Over 76% lens transmission was measured which surpassed the program goal of 75%. One-foot long receiver sections were assembled and subjected to evaluation tests at Sandia National Laboratories. A first group had some problem with cell delamination and voids but a second group performed very well, indicating that a full size receiver would pass the full qualification test. Cost information was updated and presented in the report. The cost study indicated that the Solar Engineering Applications Corporation concentrator system can exceed the DOE electricity cost goals of less than 6cents per KW-hr. 33 figs., 11 tabs.

  6. Benchmarking concentrating photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Duerr, Fabian; Muthirayan, Buvaneshwari; Meuret, Youri; Thienpont, Hugo

    2010-08-01

    Integral to photovoltaics is the need to provide improved economic viability. To achieve this goal, photovoltaic technology has to be able to harness more light at less cost. A large variety of concentrating photovoltaic concepts has provided cause for pursuit. To obtain a detailed profitability analysis, a flexible evaluation is crucial for benchmarking the cost-performance of this variety of concentrating photovoltaic concepts. To save time and capital, a way to estimate the cost-performance of a complete solar energy system is to use computer aided modeling. In this work a benchmark tool is introduced based on a modular programming concept. The overall implementation is done in MATLAB whereas Advanced Systems Analysis Program (ASAP) is used for ray tracing calculations. This allows for a flexible and extendable structuring of all important modules, namely an advanced source modeling including time and local dependence, and an advanced optical system analysis of various optical designs to obtain an evaluation of the figure of merit. An important figure of merit: the energy yield for a given photovoltaic system at a geographical position over a specific period, can be calculated.

  7. Advanced photovoltaic solar array development

    NASA Technical Reports Server (NTRS)

    Kurland, Richard M.; Stella, Paul

    1989-01-01

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

  8. Advanced Rainbow Solar Photovoltaic Arrays

    NASA Technical Reports Server (NTRS)

    Mardesich, Nick; Shields, Virgil

    2003-01-01

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

  9. 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.

  10. Photovoltaic systems perspective

    NASA Technical Reports Server (NTRS)

    Sutton, P. D.; Jones, G. J.

    1979-01-01

    This paper summarizes the elements of photovoltaic power system and clarifies the terminology currently used. The relationship of system efficiency and cost is described particularly for the Balance of Photovoltaic System (BOPS) area. The current status of the BOPS development activity is described. The photovoltaic systems terminology is found to be on the road to standardization. Power conditioning, energy storage, and support structure are found to be BOPS cost and/or efficiency drivers. Although the current BOPS activity has identified low-cost/high-efficiency components, further development work is necessary.

  11. Concentrating photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Dupas, A.

    1982-11-01

    Various configurations for concentrating photovoltaic systems are described and their operating principles are explained. The effects of temperature and series resistance on system efficiency are discussed. As an example, the french family of photovoltaic concentrating systems, SOPHOCLE, is described. The SOPHOCLE family of generators is characterized by the use of a heliostat with altazimuth mounting and by the choice of medium concentration (C=45) by fresnel lenses on silicon cells.

  12. Advanced Photovoltaic Inverter Functionality using 500 kW Power Hardware-in-Loop Complete System Laboratory Testing: Preprint

    SciTech Connect

    Mather, B. A.; Kromer, M. A.; Casey, L.

    2013-01-01

    With the increasing penetration of distribution connected photovoltaic (PV) systems, more and more PV developers and utilities are interested in easing future PV interconnection concerns by mitigating some of the impacts of PV integration using advanced PV inverter controls and functions. This paper describes the testing of a 500 kW PV inverter using Power Hardware-in-Loop (PHIL) testing techniques. The test setup is described and the results from testing the inverter in advanced functionality modes, not commonly used in currently interconnected PV systems, are presented. PV inverter operation under PHIL evaluation that emulated both the DC PV array connection and the AC distribution level grid connection are shown for constant power factor (PF) and constant reactive power (VAr) control modes. The evaluation of these modes was completed under varying degrees of modeled PV variability.

  13. Photovoltaic power systems workshop

    NASA Technical Reports Server (NTRS)

    Killian, H. J.; Given, R. W.

    1978-01-01

    Discussions are presented on apparent deficiencies in NASA planning and technology development relating to a standard power module (25-35 kW) and to future photovoltaic power systems in general. Topics of discussion consider the following: (1) adequate studies on power systems; (2) whether a standard power system module should be developed from a standard spacecraft; (3) identification of proper approaches to cost reduction; (4) energy storage avoidance; (5) attitude control; (6) thermal effects of heat rejection on solar array configuration stability; (7) assembly of large power systems in space; and (8) factoring terrestrial photovoltaic work into space power systems for possible payoff.

  14. 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.

  15. Terrestrial Photovoltaic System Analysis.

    DTIC Science & Technology

    1980-07-01

    tanks is cost Iv (P3 per Watt) bet’aulse ofanll-t distri bution svsteri and uise if exit ic heat. 01latgr 1 C 01:1 li:-iorn. ItIe r e1o0re iS t i a1t...install an array size ot at least 300i kW. The estimated initial instal led cost oi th., cmibiiid phit,)voltaic!tLier- mal system is $28 per watt. The use...conclusion, theretore, is that ;al electric - only photovoltaic system is more cost effective. The daily average power requirement of the

  16. Photovoltaics. [research and development of terrestrial electric power systems

    NASA Technical Reports Server (NTRS)

    Smith, J. L.

    1981-01-01

    The federal government has sponsored a program of research and development on terrestrial photovoltaic systems that is designed to reduce the costs of such systems through technological advances. There are many potential paths to lower system costs, and successful developments have led to increased private investment in photovoltaics. The prices for photovoltaic collectors and systems that appear to be achievable within this decade offer hope that the systems will soon be attractive in utility applications within the United States. Most of the advances achieved will also be directly applicable to the remote markets in which photovoltaic systems are now commercially successful

  17. 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.

  18. Photovoltaic module mounting system

    SciTech Connect

    Miros, Robert H. J.; Mittan, Margaret Birmingham; Seery, Martin N; Holland, Rodney H

    2012-04-17

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  19. Photovoltaic module mounting system

    SciTech Connect

    Miros, Robert H. J.; Mittan, Margaret Birmingham; Seery, Martin N; Holland, Rodney H

    2012-09-18

    A solar array mounting system having unique installation, load distribution, and grounding features, and which is adaptable for mounting solar panels having no external frame. The solar array mounting system includes flexible, pedestal-style feet and structural links connected in a grid formation on the mounting surface. The photovoltaic modules are secured in place via the use of attachment clamps that grip the edge of the typically glass substrate. The panel mounting clamps are then held in place by tilt brackets and/or mid-link brackets that provide fixation for the clamps and align the solar panels at a tilt to the horizontal mounting surface. The tilt brackets are held in place atop the flexible feet and connected link members thus creating a complete mounting structure.

  20. Photovoltaic Systems Modeling and Analysis

    NASA Astrophysics Data System (ADS)

    Ali, Mir Shahed

    2010-11-01

    This thesis deals with the implementation of generalized photovoltaic model and integration of the same with 7-bus electrical utility system to evaluate the impact that the photovoltaic generator have on the utility system. Among all the impacts that the photovoltaic generator have on the utility system, voltage rise of the power distribution line at the position where the Photovoltaic generator is connected due to reverse power flow from the photovoltaic model has been one of the major problem. Therefore, this thesis proposes the steady-state simulations to evaluate the effectiveness of battery-integrated PV system on avoiding the over voltage problem. Further, fault analysis is done to study the effect of the PV model on the utility network during faults and it is deduced that the impact of the PV model on the utility system voltage during faults is nominal. The photovoltaic model/generator and the 7-bus utility system is developed using Matlab/Simulink software package. The developed photovoltaic model can be represented as PV cell, module or an array. The model is developed with icons that are easy to understand. The developed model takes into consideration cell's working temperature, amount of sunlight (irradiance) available, voltage of the circuit when the circuit is open and current of the circuit when it is shorted. The developed Photovoltaic model is then integrated with a Li-ion battery, over here battery serves two purposes first it will store the excess power from the Photovoltaic generator if any, during the day time and in night the battery acts as an generator and deliver the power to the utility or connected load with the help of an invertors.

  1. A Photovoltaic System Payback Calculator

    SciTech Connect

    Riley, Daniel M.; Fleming, Jeffrey E.; Gallegos, Gerald R.

    2016-06-01

    The Roof Asset Management Program (RAMP) is a DOE NNSA initiative to manage roof repairs and replacement at NNSA facilities. In some cases, installation of a photovoltaic system on new roofs may be possible and desired for financial reasons and to meet federal renewable energy goals. One method to quantify the financial benefits of PV systems is the payback period, or the length of time required for a PV system to generate energy value equivalent to the system's cost. Sandia Laboratories created a simple spreadsheet-based solar energy valuation tool for use by RAMP personnel to quickly evaluate the estimated payback period of prospective or installed photovoltaic systems.

  2. Overview of NREL's Photovoltaic Advanced R D Project

    SciTech Connect

    Surek, T.

    1992-01-01

    The National Renewable Energy Laboratory's (NREL's) Photovoltaic Advanced Research and Development (PV AR D) Project supports the US Department of Energy's National Photovoltaics Program in assisting the development and commercialization of photovoltaics (PV) energy technology. The NREL program is implemented through in-house research and subcontracts, with over 50% of the annual budget awarded through competitive solicitations to universities, large and small businesses, and other research centers. These activities include cost-shared, multiyear, government/industry partnerships and technology initiatives. The research has resulted in a better fundamental understanding of materials, devices, and processes, the achievement of record efficiencies in nearly all PV technology areas, the identification of promising new approaches to low-cost photovoltaics, and the introduction of new PV technology products into system experiments and PV markets. This paper presents an overview of NREL's PV AR D Project in terms of project organization and budgets, near- and long-term project objectives, research participants, and current and future research directions. Recent progress in the in-house and subcontracted research activities is described. 4 refs.

  3. Advancing colloidal quantum dot photovoltaic technology

    NASA Astrophysics Data System (ADS)

    Cheng, Yan; Arinze, Ebuka S.; Palmquist, Nathan; Thon, Susanna M.

    2016-06-01

    Colloidal quantum dots (CQDs) are attractive materials for solar cells due to their low cost, ease of fabrication and spectral tunability. Progress in CQD photovoltaic technology over the past decade has resulted in power conversion efficiencies approaching 10%. In this review, we give an overview of this progress, and discuss limiting mechanisms and paths for future improvement in CQD solar cell technology.We briefly summarize nanoparticle synthesis and film processing methods and evaluate the optoelectronic properties of CQD films, including the crucial role that surface ligands play in materials performance. We give an overview of device architecture engineering in CQD solar cells. The compromise between carrier extraction and photon absorption in CQD photovoltaics is analyzed along with different strategies for overcoming this trade-off. We then focus on recent advances in absorption enhancement through innovative device design and the use of nanophotonics. Several light-trapping schemes, which have resulted in large increases in cell photocurrent, are described in detail. In particular, integrating plasmonic elements into CQD devices has emerged as a promising approach to enhance photon absorption through both near-field coupling and far-field scattering effects. We also discuss strategies for overcoming the single junction efficiency limits in CQD solar cells, including tandem architectures, multiple exciton generation and hybrid materials schemes. Finally, we offer a perspective on future directions for the field and the most promising paths for achieving higher device efficiencies.

  4. Voltage Regulators for Photovoltaic Systems

    NASA Technical Reports Server (NTRS)

    Delombard, R.

    1986-01-01

    Two simple circuits developed to provide voltage regulation for highvoltage (i.e., is greater than 75 volts) and low-voltage (i.e., is less than 36 volts) photovoltaic/battery power systems. Use of these circuits results in voltage regulator small, low-cost, and reliable, with very low power dissipation. Simple oscillator circuit controls photovoltaic-array current to regulate system voltage and control battery charging. Circuit senses battery (and system) voltage and adjusts array current to keep battery voltage from exceeding maximum voltage.

  5. Study on photovoltaic power system on ships

    SciTech Connect

    Katagi, Takeshi; Fujii, Yoshimi; Nishikawa, Eiichi; Hashimoto, Takeshi

    1995-11-01

    This paper presents the application of photovoltaic power systems to ships. Two types of leisure or fishing boats powered by photovoltaics are designed. The boats described are single hull and catamaran type with twin hulls. The design of a new electric power system using a photovoltaic power system in a harbor ship having 20 tons is also proposed. The results of this study show that the photovoltaic power system can apply to small ships.

  6. An Advanced Photovoltaic Array Regulator Module

    NASA Technical Reports Server (NTRS)

    Button, Robert M.

    1996-01-01

    Current trends in satellite design are focused on developing small, reliable, and inexpensive spacecraft. To that end, a modular power management and distribution system is proposed which will help transition the aerospace industry towards an assembly line approach to building spacecraft. The modular system is based on an innovative DC voltage boost converter called the Series Connected Boost Unit (SCBU). The SCBU uses any isolating DC-DC converter and adds a unique series connection. This simple modification provides the SCBU topology with many advantages over existing boost converters. Efficiencies of 94-98%, power densities above 1,000 W/kg, and inherent fault tolerance are just a few of the characteristics presented. Limitations of the SCBU technology are presented, and it is shown that the SCBU makes an ideal photovoltaic an-ay regulator. A set of photovoltaic power system requirements are presented that can be applied to almost any low Earth orbit satellite. Finally, a modular design based on the series connected boost unit is outlined and functional descriptions of the components are given.

  7. Intermediate photovoltaic system/utility interface experience

    NASA Astrophysics Data System (ADS)

    Biringer, K. L.; McDowell, J. F.; Rogers, C. B.; Haskins, D. E.

    A description is given of 11 intermediate photovoltaic application projects, including the Arizona Public Service Company project, the E-Systems 27 kW photovoltaic concentrator application experiment, a 110 kW photovoltaic application experiment in Orlando, Florida, the Lea County photovoltaic flat plate photovoltaic experiment in southeastern New Mexico, the Mt. Laguna photovoltaic flat plate installation in California, the San Bernardino 35 kW photovoltaic flat plate project in California, and the Solar Power flat plate photovoltaic experiment in Massachusetts. It is pointed out that the most significant point to be made relative to the interface of photovoltaic systems with the utility grid is that it can be done successfully.

  8. Evaluation of advanced R and D topics in photovoltaics

    NASA Technical Reports Server (NTRS)

    Surek, T.

    1982-01-01

    An evaluation of advanced research and development topics in photovoltaic that is summarized. The intent was to develop priorities in a list of advanced research and development activities. Thirty-five activities in 10 major categories were evaluated by their contributions to basic scientific advances, potential impact on further technology development by private industry, and priorities for federal advanced research and development funding.

  9. Photovoltaic Systems for Government Agencies

    DTIC Science & Technology

    1994-02-01

    i -- • • ;__ S• .... S,<, - Loca ted in the Adirondacks this photovoltaic system powers a facility offering visitors a clean, odorless, and...current depends on type of metal, composition of the soil, salinity of water, and surface area of metal to be protected. Historically, cathodic

  10. Photovoltaics for high capacity space power systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.

    1988-01-01

    The anticipated energy requirements of future space missions will grow by factors approaching 100 or more, particularly as a permanent manned presence is established in space. The advances that can be expected in solar array performance and lifetime, when coupled with advanced, high energy density storage batteries and/or fuel cells, will continue to make photovoltaic energy conversion a viable power generating option for the large systems of the future. The specific technologies required to satisfy any particular set of power requirements will vary from mission to mission. Nonetheless, in almost all cases the technology push will be toward lighter weight and higher efficiency, whether of solar arrays or storage devices. This paper will describe the content and direction of the current NASA program in space photovoltaic technology. The paper will also discuss projected system level capabilities of photovoltaic power systems in the context of some of the new mission opportunities under study by NASA, such as a manned lunar base, and a manned visit to Mars.

  11. Photovoltaics for high capacity space power systems

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.

    1988-01-01

    The anticipated energy requirements of future space missions will grow by factors approaching 100 or more, particularly as a permanent manned presence is established in space. The advances that can be expected in solar array performance and lifetime, when coupled with advanced, high energy density storage batteries and/or fuel cells, will continue to make photovoltaic energy conversion a viable power generating option for the large systems of the future. The specific technologies required to satisfy any particular set of power requirements will vary from mission to mission. Nonetheless, in almost all cases the technology push will be toward lighter weight and higher efficiency, whether of solar arrays of storage devices. This paper will describe the content and direction of the current NASA program in space photovoltaic technology. The paper will also discuss projected system level capabilities of photovoltaic power systems in the context of some of the new mission opportunities under study by NASA, such as a manned lunar base, and a manned visit to Mars.

  12. Photovoltaic Systems Test Facilities: Existing capabilities compilation

    NASA Technical Reports Server (NTRS)

    Volkmer, K.

    1982-01-01

    A general description of photovoltaic systems test facilities (PV-STFs) operated under the U.S. Department of Energy's photovoltaics program is given. Descriptions of a number of privately operated facilities having test capabilities appropriate to photovoltaic hardware development are given. A summary of specific, representative test capabilities at the system and subsystem level is presented for each listed facility. The range of system and subsystem test capabilities available to serve the needs of both the photovoltaics program and the private sector photovoltaics industry is given.

  13. Decentalized solar photovoltaic energy systems

    SciTech Connect

    Krupka, M. C.

    1980-09-01

    Environmental data for decentralized solar photovoltaic systems have been generated in support of the Technology Assessment of Solar Energy Systems program (TASE). Emphasis has been placed upon the selection and use of a model residential photovoltaic system to develop and quantify the necessary data. The model consists of a reference home located in Phoenix, AZ, utilizing a unique solar cell array-roof shingle combination. Silicon solar cells, rated at 13.5% efficiency at 28/sup 0/C and 100 mW/cm/sup 2/ (AMI) insolation are used to generate approx. 10 kW (peak). An all-electric home is considered with lead-acid battery storage, dc-ac inversion and utility backup. The reference home is compared to others in regions of different insolation. Major material requirements, scaled to quad levels of end-use energy include significant quantities of silicon, copper, lead, antimony, sulfuric acid and plastics. Operating residuals generated are negligible with the exception of those from the storage battery due to a short (10-year) lifetime. A brief general discussion of other environmental, health, and safety and resource availability impacts is presented. It is suggested that solar cell materials production and fabrication may have the major environmental impact when comparing all facets of photovoltaic system usage. Fabrication of the various types of solar cell systems involves the need, handling, and transportation of many toxic and hazardous chemicals with attendant health and safety impacts. Increases in production of such materials as lead, antimony, sulfuric acid, copper, plastics, cadmium and gallium will be required should large scale usage of photovoltaic systems be implemented.

  14. Progress in photovoltaic system and component improvements

    SciTech Connect

    Thomas, H.P.; Kroposki, B.; McNutt, P.; Witt, C.E.; Bower, W.; Bonn, R.; Hund, T.D.

    1998-07-01

    The Photovoltaic Manufacturing Technology (PVMaT) project is a partnership between the US government (through the US Department of Energy [DOE]) and the PV industry. Part of its purpose is to conduct manufacturing technology research and development to address the issues and opportunities identified by industry to advance photovoltaic (PV) systems and components. The project was initiated in 1990 and has been conducted in several phases to support the evolution of PV industrial manufacturing technology. Early phases of the project stressed PV module manufacturing. Starting with Phase 4A and continuing in Phase 5A, the goals were broadened to include improvement of component efficiency, energy storage and manufacturing and system or component integration to bring together all elements for a PV product. This paper summarizes PV manufacturers` accomplishments in components, system integration, and alternative manufacturing methods. Their approaches have resulted in improved hardware and PV system performance, better system compatibility, and new system capabilities. Results include new products such as Underwriters Laboratories (UL)-listed AC PV modules, modular inverters, and advanced inverter designs that use readily available and standard components. Work planned in Phase 5A1 includes integrated residential and commercial roof-top systems, PV systems with energy storage, and 300-Wac to 4-kWac inverters.

  15. Photovoltaic power system reliability considerations

    NASA Technical Reports Server (NTRS)

    Lalli, V. R.

    1980-01-01

    An example of how modern engineering and safety techniques can be used to assure the reliable and safe operation of photovoltaic power systems is presented. This particular application is for a solar cell power system demonstration project designed to provide electric power requirements for remote villages. The techniques utilized involve a definition of the power system natural and operating environment, use of design criteria and analysis techniques, an awareness of potential problems via the inherent reliability and FMEA methods, and use of fail-safe and planned spare parts engineering philosophy.

  16. Photovoltaic pump systems

    NASA Astrophysics Data System (ADS)

    Klockgether, J.; Kiessling, K. P.

    1983-09-01

    Solar pump systems for the irrigation of fields and for water supply in regions with much sunshine are discussed. For surface water and sources with a hoisting depth of 12 m, a system with immersion pumps is used. For deep sources with larger hoisting depths, an underwater motor pump was developed. Both types of pump system meet the requirements of simple installation and manipulation, safe operation, maintenance free, and high efficiency reducing the number of solar cells needed.

  17. Photovoltaic lighting system performance

    SciTech Connect

    Harrington, S.R.; Hund, T.D.

    1996-06-01

    The performance of 21 PV-powered low pressure sodium lighting systems on a multi-use has been documented in this paper. Specific areas for evaluation include the vandal resistant PV modules, constant voltage and on/off PV charge controllers, flooded deep-cycle lead-antimony and valve regulated lead-acid (VLRA) gel batteries, and low pressure sodium ballasts and lights. The PV lighting system maintenance intervals and lessons learned have been documented over the past 2.5 years. The above performance data has shown that with careful hardware selection, installation, and maintenance intervals the PV lighting systems will operate reliably.

  18. Dynamically reconfigurable photovoltaic system

    SciTech Connect

    Okandan, Murat; Nielson, Gregory N.

    2016-12-27

    A PV system composed of sub-arrays, each having a group of PV cells that are electrically connected to each other. A power management circuit for each sub-array has a communications interface and serves to connect or disconnect the sub-array to a programmable power grid. The power grid has bus rows and bus columns. A bus management circuit is positioned at a respective junction of a bus column and a bus row and is programmable through its communication interface to connect or disconnect a power path in the grid. As a result, selected sub-arrays are connected by selected power paths to be in parallel so as to produce a low system voltage, and, alternately in series so as to produce a high system voltage that is greater than the low voltage by at least a factor of ten.

  19. Dynamically reconfigurable photovoltaic system

    DOEpatents

    Okandan, Murat; Nielson, Gregory N.

    2016-05-31

    A PV system composed of sub-arrays, each having a group of PV cells that are electrically connected to each other. A power management circuit for each sub-array has a communications interface and serves to connect or disconnect the sub-array to a programmable power grid. The power grid has bus rows and bus columns. A bus management circuit is positioned at a respective junction of a bus column and a bus row and is programmable through its communication interface to connect or disconnect a power path in the grid. As a result, selected sub-arrays are connected by selected power paths to be in parallel so as to produce a low system voltage, and, alternately in series so as to produce a high system voltage that is greater than the low voltage by at least a factor of ten.

  20. Photovoltaic-electrolyzer system transient simulation results

    SciTech Connect

    Leigh, R.W.; Metz, P.D.; Michalek, K.

    1986-05-01

    Brookhaven National Laboratory has developed a Hydrogen Technology Evaluation Center to illustrate advanced hydrogen technology. The first phase of this effort investigated the use of solar energy to produce hydrogen from water via photovoltaic-powered electrolysis. A coordinated program of system testing, computer simulation, and economic analysis has been adopted to characterize and optimize the photovoltaic-electrolyzer system. This paper presents the initial transient simulation results. Innovative features of the modeling include the use of real weather data, detailed hourly modeling of thermal characteristics of the PV array and of system control strategies, and examination of systems over a wide range of power and voltage ratings. The transient simulation system TRNSYS was used, incorporating existing, modified or new component subroutines as required. For directly coupled systems, the authors found the PV array voltage which maximizes hydrogen production to be quite near the nominal electrolyzer voltage for a wide range of PV array powers. The array voltage which maximizes excess electricity production is slightly higher. The use of an ideal (100 percent efficient) maximum power tracking system provides only a six percent increase in annual hydrogen production. An examination of the effect of the PV array tilt indicates, as expected, that annual hydrogen production is insensitive to tilt angle within +-20 deg of latitude. Summer production greatly exceeds winter generation. Tilting the array, even to 90 deg, produces no significant increase in winter hydrogen production.

  1. Advanced tendencies in development of photovoltaic cells for power engineering

    NASA Astrophysics Data System (ADS)

    Strebkov, D. S.

    2015-01-01

    Development of solar power engineering must be based on original innovative Russian and world technologies. It is necessary to develop promising Russian technologies of manufacturing of photovoltaic cells and semiconductor materials: chlorine-free technology for obtaining solar silicon; matrix solar cell technology with an efficiency of 25-30% upon the conversion of concentrated solar, thermal, and laser radiation; encapsulation technology for high-voltage silicon solar modules with a voltage up to 1000 V and a service life up to 50 years; new methods of concentration of solar radiation with the balancing illumination of photovoltaic cells at 50-100-fold concentration; and solar power systems with round-the-clock production of electrical energy that do not require energy storage devices and reserve sources of energy. The advanced tendency in silicon power engineering is the use of high-temperature reactions in heterogeneous modular silicate solutions for long-term (over one year) production of heat and electricity in the autonomous mode.

  2. Recent progress in space photovoltaic systems

    NASA Technical Reports Server (NTRS)

    Brandhorst, Henry W., Jr.; Flood, Dennis J.; Weinberg, Irving

    1987-01-01

    Key issues and opportunities in space photovoltaic research and technology relative to future NASA mission requirements and drivers are addressed. Examples are given of space missions and/or operational capabilities on NASA's planning horizon presenting major technology challenges to the use of photovoltaic power generation in space. The status of cell R and D and the performance goals to be met by space photovoltaic power systems to remain competitive are described.

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

    SciTech Connect

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

    2015-09-01

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

  4. Cost and Performance Model for Photovoltaic Systems

    NASA Technical Reports Server (NTRS)

    Borden, C. S.; Smith, J. H.; Davisson, M. C.; Reiter, L. J.

    1986-01-01

    Lifetime cost and performance (LCP) model assists in assessment of design options for photovoltaic systems. LCP is simulation of performance, cost, and revenue streams associated with photovoltaic power systems connected to electric-utility grid. LCP provides user with substantial flexibility in specifying technical and economic environment of application.

  5. Recent Advances in Wide-Bandgap Photovoltaic Polymers.

    PubMed

    Cai, Yunhao; Huo, Lijun; Sun, Yanming

    2017-03-29

    The past decade has witnessed significant advances in the field of organic solar cells (OSCs). Ongoing improvements in the power conversion efficiency of OSCs have been achieved, which were mainly attributed to the design and synthesis of novel conjugated polymers with different architectures and functional moieties. Among various conjugated polymers, the development of wide-bandgap (WBG) polymers has received less attention than that of low-bandgap and medium-bandgap polymers. Here, we briefly summarize recent advances in WBG polymers and their applications in organic photovoltaic (PV) devices, such as tandem, ternary, and non-fullerene solar cells. Addtionally, we also dissuss the application of high open-circuit voltage tandem solar cells in PV-driven electrochemical water dissociation. We mainly focus on the molecular design strategies, the structure-property correlations, and the photovoltaic performance of these WBG polymers. Finally, we extract empirical regularities and provide invigorating perspectives on the future development of WBG photovoltaic materials.

  6. A challenging future for improved photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Allen, Douglas M.

    The expansion of space requirements creates opportunities and priorities for power production, thus driving the development of innovative technologies. Key requirements for improving photovoltaics are outlined including cell efficiency, specific power, packaging, reliability, and affordability issues. The competition faced by photovoltaic cells is discussed with specific reference to solar dynamics and nuclear radioisotope thermal generator systems.

  7. Photovoltaic power generation system free of bypass diodes

    SciTech Connect

    Lentine, Anthony L.; Okandan, Murat; Nielson, Gregory N.

    2015-07-28

    A photovoltaic power generation system that includes a solar panel that is free of bypass diodes is described herein. The solar panel includes a plurality of photovoltaic sub-modules, wherein at least two of photovoltaic sub-modules in the plurality of photovoltaic sub-modules are electrically connected in parallel. A photovoltaic sub-module includes a plurality of groups of electrically connected photovoltaic cells, wherein at least two of the groups are electrically connected in series. A photovoltaic group includes a plurality of strings of photovoltaic cells, wherein a string of photovoltaic cells comprises a plurality of photovoltaic cells electrically connected in series. The strings of photovoltaic cells are electrically connected in parallel, and the photovoltaic cells are microsystem-enabled photovoltaic cells.

  8. Advanced Photovoltaic Solar Array program status

    NASA Technical Reports Server (NTRS)

    Kurland, Richard M.; Stella, Paul M.

    1989-01-01

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

  9. Photovoltaics: Solar electric power systems

    NASA Astrophysics Data System (ADS)

    1980-02-01

    The operation and uses of solar cells and the National Photovoltaic Program are briefly described. Eleven DOE photovoltaic application projects are described including forest lookout towers; Wilcox Memorial Hospital in Hawaii; WBNO daytime AM radio station; Schuchuli Indian Village; Meade, Nebraska, agricultural experiment; Mt. Laguna Air Force Station; public schools and colleges; residential applications; and Sea World of Florida.

  10. 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)

  11. Advanced photovoltaic solar array - Design and performance

    NASA Technical Reports Server (NTRS)

    Kurland, Richard; Stella, Paul

    1992-01-01

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

  12. Switching model photovoltaic pumping system

    NASA Astrophysics Data System (ADS)

    Anis, Wagdy R.; Abdul-Sadek Nour, M.

    Photovoltaic (PV) pumping systems are widely used due to their simplicity, high reliability and low cost. A directly-coupled PV pumping system is the most reliable and least-cost PV system. The d.c. motor-pump group is not, however, working at its optimum operating point. A battery buffered PV pumping system introduces a battery between the PV array and the d.c. motor-pump group to ensure that the motor-pump group is operating at its optimum point. The size of the battery storage depends on system economics. If the battery is fully charged while solar radiation is available, the battery will discharge through the load while the PV array is disconnected. Hence, a power loss takes place. To overcome the above mentioned difficulty, a switched mode PV pumping is proposed. When solar radiation is available and the battery is fully charged, the battery is disconnected and the d.c. motor-pump group is directly coupled to the PV array. To avoid excessive operating voltage for the motor, a part of the PV array is switched off to reduce the voltage. As a result, the energy loss is significantly eliminated. Detailed analysis of the proposed system shows that the discharged water increases by about 10% when compared with a conventional battery-buffered system. The system transient performance just after the switching moment shows that the system returns to a steady state in short period. The variations in the system parameters lie within 1% of the rated values.

  13. Photovoltaic system criteria documents. Volume 5: Safety criteria for photovoltaic applications

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    Methodology is described for determining potential safety hazards involved in the construction and operation of photovoltaic power systems and provides guidelines for the implementation of safety considerations in the specification, design and operation of photovoltaic systems. Safety verification procedures for use in solar photovoltaic systems are established.

  14. Energy losses in photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Anis, Wagdy R.; Nour, M. Abdulsadek

    1994-10-01

    The maximum power generated by photovoltaic (PV) arrays is not fully used. During summer, the main cause for the energy loss is the system design that necessitates an oversizing of the PV array to supply the load during the winter season when the solar energy is limited. Other reasons that cause energy loss are: the mismatch between the array and the load or battery, the loss in the batteries, and the loss due to the PV array disconnect. The array disconnect loss takes place during summer season when the battery is fully charged. To avoid the disconnect loss, a novel battery voltage regulator (BVR) is used. This supplies the load directly from the array when the battery is fully charged. Energy losses have been analyzed and divided into fundamental (unavoidable) and non-fundamental losses. Both conventional (using a conventional BVR) and new (using a novel BVR) PV systems are studied. A load that consumes constant power for 24 h a day through the year is considered. The climatic condition of Cairo city is taken as the test case.

  15. Plasma chamber testing of advanced photovoltaic solar array coupons

    NASA Astrophysics Data System (ADS)

    Hillard, G. Barry

    1994-05-01

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

  16. Photovoltaic power system for a lunar base

    NASA Astrophysics Data System (ADS)

    Karia, Kris

    An assessment is provided of the viability of using photovoltaic power technology for lunar base application during the initial phase of the mission. The initial user power demands were assumed to be 25 kW (daytime) and 12.5 kW (night time). The effect of lunar adverse environmental conditions were also considered in deriving the photovoltaic power system concept. The solar cell array was found to impose no more design constraints than those solar arrays currently being designed for spacecraft and the Space Station Freedom. The long lunar night and the need to store sufficient energy to sustain a lunar facility during this period was found to be a major design driver. A photovoltaic power system concept was derived using high efficiency thin GaAs solar cells on a deployable flexible Kapton blanket. The solar array design was sized to generate sufficient power for daytime use and for a regenerative fuel cell (RFC) energy storage system to provide power during the night. Solar array sun-tracking is also proposed to maximize the array power output capability. The system launch mass was estimated to be approximately 10 metric tons. For mission application of photovoltaic technology other issues have to be addressed including the constraints imposed by launch vehicle, safety, and cost. For the initial phase of the mission a photovoltaic power system offers a safe option.

  17. A novel photovoltaic power system which uses a large area concentrator mirror

    NASA Technical Reports Server (NTRS)

    Arrison, Anne; Fatemi, Navid

    1987-01-01

    A preliminary analysis has been made of a novel photovoltaic power system concept. The system is composed of a small area, dense photovoltaic array, a large area solar concentrator, and a battery system for energy storage. The feasibility of such a system is assessed for space power applications. The orbital efficiency, specific power, mass, and area of the system are calculated under various conditions and compared with those for the organic Rankine cycle solar dynamic system proposed for Space Station. Near term and advanced large area concentrator photovoltaic systems not only compare favorably to solar dynamic systems in terms of performance but offer other benefits as well.

  18. Photovoltaic power systems for rural areas of developing countries

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.; Bifano, W. J.; Hein, G. F.; Ratajczak, A. F.

    1979-01-01

    Systems technology, reliability, and present and projected costs of photovoltaic systems are discussed using data derived from NASA, Lewis Research Center experience with photovoltaic systems deployed with a variety of users. Operating systems in two villages, one in Upper Volta and the other in southwestern Arizona are described. Energy cost comparisons are presented for photovoltaic systems versus alternative energy sources. Based on present system technology, reliability, and costs, photovoltaics provides a realistic energy option for developing nations.

  19. Photovoltaic systems for export application. Informal report

    SciTech Connect

    Duffy, J.; Campbell, H.; Sajo, A.; Sanz, E.

    1988-01-31

    One approach to improving the competitiveness of photovoltaic systems is the development of designs specifically for export applications. In other words, where is it appropriate in a system design to incorporate components manufactured and/or assembled in the receiving country in order to improve the photovoltaic exports from the US? What appears to be needed is a systematic method of evaluating the potential for export from the US of PV systems for various application in different countries. Development of such a method was the goal of this project.

  20. Design considerations for Mars photovoltaic power systems

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Appelbaum, Joseph

    1990-01-01

    Considerations for operation of a photovoltaic power system on Mars are discussed with reference to Viking Lander data. The average solar insolation at Mars is 590 W/sq m, which is reduced yet further by atmospheric dust. Of major concern are dust storms, which have been observed to occur on local as well as on global scales, and their effect on solar array output. While atmospheric opacity may rise to values ranging from 3 to 9, depending on storm severity, there is still an appreciable large diffuse illumination, even at high opacities, so that photovoltaic operation is still possible. If the power system is to continue to generate power even on high-optical-opacity (i.e., dusty atmosphere) days, it is important that the photovoltaic system be designed to collect diffuse irradiance as well as direct. Energy storage will be required for operation during the night. Temperature and wind provide additional considerations for array design.

  1. Performance of photovoltaic electrolysis system

    NASA Astrophysics Data System (ADS)

    Esteve, D.; Ganibal, C.; Steinmetz, D.; Vialaron, A.

    A photovoltaic generator with concentrated light is combined with a water electrolysis cell in an effort to further the development of solar energy utilization. SOPHOCLE, a photovoltaic generator with limited concentration of energy, is a heliostat of the altazimuth type, consisting of an optical device to focus the sunlight on the photocells, a tracking device to follow the position of the sun, and a cooling device to allow dissipation of thermal energy. The combined cost and performance of SOPHOCLE gives an overall efficiency of 9 percent (for direct solar radiation). A power conditioning device matches the generator photocell characteristics with the electrolysis cell to give maximum hydrogen production. Hydrogen can be produced by this method with an overall efficiency of 7 percent.

  2. Review of hydrogen production with photovoltaic electrolysis systems

    NASA Astrophysics Data System (ADS)

    Fischer, M.

    Characteristics and performance of H2 production by means of photovoltaic solar energy conversion and water electrolysis are studied and discussed. Experimental results of a small system consisting of a polycrystalline solar cell generator, water electrolysis and power conditioning are compared with calculated results of a system simulation model. The stationary and dynamic behavior of the system and components, and the efficiency and performance of power conditioning are investigated. For an optimized and reliable operation of photovoltaic electrolyzer systems, the behavior of electrolysis at part-load and overload, the start-up and shut-down behavior, and the corrosion and degradation effects are important aspects. The status and further improvements of advanced electrolysis are discussed, as well as results of system analysis studies for future large-scale solar H2 production.

  3. Photovoltaic system testing techniques and results

    SciTech Connect

    Lashway, C. )

    1988-09-01

    For the past three years, the New Mexico Solar Energy Institute (NMSEI) has been testing and collecting data on eight intermediate size flat-plate PV systems. These data now provide a valuable data base for determining component reliability and system degradation trends. This paper discusses: the specific test techniques used by NMSEI and the reliability of photovoltaic modules revealed by this testing.

  4. Energy Systems Integration: NREL + Advanced Energy (Fact Sheet)

    SciTech Connect

    Not Available

    2015-02-01

    This fact sheet describes the collaboration between NREL and Advanced Energy Industries at the ESIF to test its advanced photovoltaic inverter technology with the ESIF's power hardware-in-the-loop system and megawatt-scale grid simulators.

  5. LDEF (Postflight), S0014 : Advanced Photovoltaic Experiment, Tray E09

    NASA Technical Reports Server (NTRS)

    1990-01-01

    LDEF (Postflight), S0014 : Advanced Photovoltaic Experiment, Tray E09 The postflight photograph was taken in the SAEF II at KSC after the experiment was removed from the LDEF. The Advanced Photovoltiac Experiment (APEX) is an active experiment completely self contained in a 12 inch deep LDEF peripheral tray. The APEX includes 155 solar cells permanently mounted on 127 removable aluminum plates of 12 different sizes, an Eppley Type HF cavity radiometer, a Digital Solar Angle Sensor, a dichroic mirror assembly, a night or dark sensor, a row of 16 bandpass filters clamped over silicon solar cell sensors, two ultraviolet exposure monitors and two solar concentrator cells with deposited aluminum (on Kapton and Mylar foil) mirrors. An aluminum sub-structure provides a mounting surface for experiment components and controls the field of view of solar cells. Two separate electronic systems and power sources were included, one for the experiment and data acquisition and one, the Experiment Power and Data System (EPDS), for data processing and storage. The experiment structure was painted with Chemglaze Z-306 flat black paint over a Chemglaze 9924 wash primer and assembled with non-magnetic stainless steel fasteners. The tray flanges and tray clamp blocks appear as prelaunch but white paint dots on tray clamp blocks have a slight variation in color. The paint color on the upper-left clamp block is white, but paint on the right-center and lower-center clamp blocks is lightly discolored. The APEX has a number of physical changes that were observed in the flight photograph. The extent of degradation to the Chemglaze Z-306 black paint on exposed surfaces is clearer as evidenced by the amount of Chemglaze 9924 primer , a redish-brown color, visible. The difference in the amount of paint remaining may be a function of initial paint thickness, as the plate covering the tray's center section was painted at a different time than the other two plates. The small gold colored

  6. Application and design of solar photovoltaic system

    NASA Astrophysics Data System (ADS)

    Tianze, Li; Hengwei, Lu; Chuan, Jiang; Luan, Hou; Xia, Zhang

    2011-02-01

    Solar modules, power electronic equipments which include the charge-discharge controller, the inverter, the test instrumentation and the computer monitoring, and the storage battery or the other energy storage and auxiliary generating plant make up of the photovoltaic system which is shown in the thesis. PV system design should follow to meet the load supply requirements, make system low cost, seriously consider the design of software and hardware, and make general software design prior to hardware design in the paper. To take the design of PV system for an example, the paper gives the analysis of the design of system software and system hardware, economic benefit, and basic ideas and steps of the installation and the connection of the system. It elaborates on the information acquisition, the software and hardware design of the system, the evaluation and optimization of the system. Finally, it shows the analysis and prospect of the application of photovoltaic technology in outer space, solar lamps, freeways and communications.

  7. Monitoring the battery status for photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Kim, Myungsoo; Hwang, Euijin

    Photovoltaic power systems in Korea have been installed in remote islands where it is difficult to connect the utilities. Lead/acid batteries are used as an energy storage device for the stand-alone photovoltaic system. Hence, monitoring the battery status of photovoltaic systems is quite important to extend the total system service life. To monitor the state-of-charge of batteries, we adopted a current interrupt technique to measure the internal resistance of the battery. The internal resistance increases at the end of charge/discharge steps and also with cycles. The specific gravity of the electrolyte was measured in relation to the state-of-charge. A home-made optical hydrometer was utilized for automatic monitoring of the specific gravity. It is shown that the specific gravity and stratification increase with cycle number. One of the photovoltaic systems in a remote island, Ho-do, which has 90 kW peak power was checked for actual operational conditions such as solar generation, load, and battery status.

  8. Space Environment Testing of Photovoltaic Array Systems

    NASA Technical Reports Server (NTRS)

    Phillips, Brandon; Schneider, Todd A.; Vaughn, Jason A.; Wright, Kenneth H.

    2015-01-01

    To successfully operate a photovoltaic (PV) array system in space requires planning and testing to account for the effects of the space environment. It is critical to understand space environment interactions not only on the PV components, but also the array substrate materials, wiring harnesses, connectors, and protection circuitry.

  9. The World's Largest Photovoltaic Concentrator System.

    ERIC Educational Resources Information Center

    Smith, Harry V.

    1982-01-01

    The Mississippi County Community College large-scale energy experiment, featuring the emerging high technology of solar electricity, is described. The project includes a building designed for solar electricity and a power plant consisting of a total energy photovoltaic system, and features two experimental developments. (MLW)

  10. Technology advances needed for photovoltaics to achieve widespread grid price parity: Widespread grid price parity for photovoltaics

    SciTech Connect

    Jones-Albertus, Rebecca; Feldman, David; Fu, Ran; Horowitz, Kelsey; Woodhouse, Michael

    2016-04-20

    To quantify the potential value of technological advances to the photovoltaics (PV) sector, this paper examines the impact of changes to key PV module and system parameters on the levelized cost of energy (LCOE). The parameters selected include module manufacturing cost, efficiency, degradation rate, and service lifetime. NREL's System Advisor Model (SAM) is used to calculate the lifecycle cost per kilowatt-hour (kWh) for residential, commercial, and utility scale PV systems within the contiguous United States, with a focus on utility scale. Different technological pathways are illustrated that may achieve the Department of Energy's SunShot goal of PV electricity that is at grid price parity with conventional electricity sources. In addition, the impacts on the 2015 baseline LCOE due to changes to each parameter are shown. These results may be used to identify research directions with the greatest potential to impact the cost of PV electricity.

  11. Hybrid Photovoltaic-Hydrogen Power Conditioning System

    NASA Astrophysics Data System (ADS)

    Garrigos, A.; Blanes, J. M.; Carrasco, J. A.; Maset, E.; Ejea, J. B.; Ferreres, A.; Sanchis, E.

    2011-10-01

    This paper explores a power conditioning unit for photovoltaic/hydrogen based energy systems. Similar power conversion techniques, compared to traditional space power systems, are applied. An S4R regulator is devised with an unregulated battery bus as primary output and a secondary path to feed and electrolyser. A modular fuel cell converter completes the system and it operates when photovoltaic energy is not available or load demand exceeds solar power, i. e. like a traditional BDR. An ancillary battery keeps the unregulated bus voltage distributed in the system and it also aids the fuel cell during transients or start-up due to its limited speed. A 1kW breadboard has been designed and implemented to corroborate the proposed system.

  12. Overview of NREL`s Photovoltaic Advanced R&D Project

    SciTech Connect

    Surek, T

    1992-01-01

    The National Renewable Energy Laboratory`s (NREL`s) Photovoltaic Advanced Research and Development (PV AR & D) Project supports the US Department of Energy`s National Photovoltaics Program in assisting the development and commercialization of photovoltaics (PV) energy technology. The NREL program is implemented through in-house research and subcontracts, with over 50% of the annual budget awarded through competitive solicitations to universities, large and small businesses, and other research centers. These activities include cost-shared, multiyear, government/industry partnerships and technology initiatives. The research has resulted in a better fundamental understanding of materials, devices, and processes, the achievement of record efficiencies in nearly all PV technology areas, the identification of promising new approaches to low-cost photovoltaics, and the introduction of new PV technology products into system experiments and PV markets. This paper presents an overview of NREL`s PV AR & D Project in terms of project organization and budgets, near- and long-term project objectives, research participants, and current and future research directions. Recent progress in the in-house and subcontracted research activities is described. 4 refs.

  13. New Markets for Solar Photovoltaic Power Systems

    NASA Astrophysics Data System (ADS)

    Thomas, Chacko; Jennings, Philip; Singh, Dilawar

    2007-10-01

    Over the past five years solar photovoltaic (PV) power supply systems have matured and are now being deployed on a much larger scale. The traditional small-scale remote area power supply systems are still important and village electrification is also a large and growing market but large scale, grid-connected systems and building integrated systems are now being deployed in many countries. This growth has been aided by imaginative government policies in several countries and the overall result is a growth rate of over 40% per annum in the sales of PV systems. Optimistic forecasts are being made about the future of PV power as a major source of sustainable energy. Plans are now being formulated by the IEA for very large-scale PV installations of more than 100 MW peak output. The Australian Government has announced a subsidy for a large solar photovoltaic power station of 154 MW in Victoria, based on the concentrator technology developed in Australia. In Western Australia a proposal has been submitted to the State Government for a 2 MW photovoltaic power system to provide fringe of grid support at Perenjori. This paper outlines the technologies, designs, management and policies that underpin these exciting developments in solar PV power.

  14. Results of testing a development module of the second-generation E-Systems concentrating photovoltaic-thermal module

    SciTech Connect

    Harrison, T D

    1982-04-01

    An actively-cooled linear Fresnel lens concentrating photovoltaic and thermal module, designed and built by E-Systems, was tested in the Photovoltaic Advanced Systems Test Facility. Physical, electrical, and thermal characteristics of the module are presented. Module performance is characterized through the use of multiple linear regression techniques.

  15. Flate-plate photovoltaic power systems handbook for Federal agencies

    NASA Technical Reports Server (NTRS)

    Cochrane, E. H.; Lawson, A. C.; Savage, C. H.

    1984-01-01

    The primary purpose is to provide a tool for personnel in Federal agencies to evaluate the viability of potential photovoltaic applications. A second objective is to provide descriptions of various photovoltaic systems installed by different Federal agencies under the Federal Photovoltaic Utilization Program so that other agencies may consider similar applications. A third objective is to share lessons learned to enable more effective procurement, design, installation, and operation of future photovoltaic systems. The intent is not to provide a complete handbook, but rather to provide a guide for Federal agency personnel with additional information incorporated by references. The steps to be followed in selecting, procuring, and installing a photovoltaic application are given.

  16. Automatic outdoor monitoring system for photovoltaic panels.

    PubMed

    Stefancich, Marco; Simpson, Lin; Chiesa, Matteo

    2016-05-01

    Long-term acquisition of solar panel performance parameters, for panels operated at maximum power point in their real environment, is of critical importance in the photovoltaic research sector. However, few options exist for the characterization of non-standard panels such as concentrated photovoltaic systems, heavily soiled or shaded panels or those operating under non-standard spectral illumination; certainly, it is difficult to find such a measurement system that is flexible and affordable enough to be adopted by the smaller research institutes or universities. We present here an instrument aiming to fill this gap, autonomously tracking and maintaining any solar panel at maximum power point while continuously monitoring its operational parameters and dissipating the produced energy without connection to the power grid. The instrument allows periodic acquisition of current-voltage curves to verify the employed maximum power point tracking approach. At the same time, with hardware schematics and software code being provided, it provides a flexible open development environment for the monitoring of non-standard generators like concentrator photovoltaic systems and to test novel power tracking approaches. The key issues, and the corresponding solutions, encountered in the design are analyzed in detail and the relevant schematics presented.

  17. Automatic outdoor monitoring system for photovoltaic panels

    NASA Astrophysics Data System (ADS)

    Stefancich, Marco; Simpson, Lin; Chiesa, Matteo

    2016-05-01

    Long-term acquisition of solar panel performance parameters, for panels operated at maximum power point in their real environment, is of critical importance in the photovoltaic research sector. However, few options exist for the characterization of non-standard panels such as concentrated photovoltaic systems, heavily soiled or shaded panels or those operating under non-standard spectral illumination; certainly, it is difficult to find such a measurement system that is flexible and affordable enough to be adopted by the smaller research institutes or universities. We present here an instrument aiming to fill this gap, autonomously tracking and maintaining any solar panel at maximum power point while continuously monitoring its operational parameters and dissipating the produced energy without connection to the power grid. The instrument allows periodic acquisition of current-voltage curves to verify the employed maximum power point tracking approach. At the same time, with hardware schematics and software code being provided, it provides a flexible open development environment for the monitoring of non-standard generators like concentrator photovoltaic systems and to test novel power tracking approaches. The key issues, and the corresponding solutions, encountered in the design are analyzed in detail and the relevant schematics presented.

  18. Reliability of photovoltaic systems: A field report

    NASA Astrophysics Data System (ADS)

    Thomas, M. G.; Fuentes, M. K.; Lashway, C.; Black, B. D.

    Performance studies and field measurements of photovoltaic systems indicate a 1 to 2% per year degradation in array energy production. The cause for much of the degradation has been identified as soiling, failed modules, and failures in interconnections. System performance evaluation continues to be complicated by the poor reliability of some power conditioning hardware that has greatly diminished the system availability and by inconsistent field ratings. Nevertheless, the current system reliability is consistent with degradation of less than 10% in 5 years and with estimates of less than 10% per year of the energy value for O and M.

  19. Reliability of photovoltaic systems - A field report

    NASA Astrophysics Data System (ADS)

    Thomas, M. G.; Fuentes, M. K.; Lashway, C.; Black, B. D.

    Performance studies and field measurements of photovoltaic systems indicate a 1-2-percent/yr degradation in array energy production. The cause for much of the degradation has been identified as soiling, failed modules, and failures in interconnections. System performance evaluation continues to be complicated by the poor reliability of some power conditioning hardware (which greatly diminished system availability) and by inconsistent field ratings. Nevertheless, the current system reliability is consistent with degradation of less than 10 percent in 5 years and with estimates of less than 10 percent/yr of the energy value for O&M.

  20. Summary of photovoltaic system performance models

    SciTech Connect

    Smith, J. H.; Reiter, L. J.

    1984-01-15

    The purpose of this study is to provide a detailed overview of photovoltaics (PV) performance modeling capabilities that have been developed during recent years for analyzing PV system and component design and policy issues. A set of 10 performance models have been selected which span a representative range of capabilities from generalized first-order calculations to highly specialized electrical network simulations. A set of performance modeling topics and characteristics is defined and used to examine some of the major issues associated with photovoltaic performance modeling. Next, each of the models is described in the context of these topics and characteristics to assess its purpose, approach, and level of detail. Then each of the issues is discussed in terms of the range of model capabilities available and summarized in tabular form for quick reference. Finally, the models are grouped into categories to illustrate their purposes and perspectives.

  1. Summary of photovoltaic system performance models

    NASA Technical Reports Server (NTRS)

    Smith, J. H.; Reiter, L. J.

    1984-01-01

    A detailed overview of photovoltaics (PV) performance modeling capabilities developed for analyzing PV system and component design and policy issues is provided. A set of 10 performance models are selected which span a representative range of capabilities from generalized first order calculations to highly specialized electrical network simulations. A set of performance modeling topics and characteristics is defined and used to examine some of the major issues associated with photovoltaic performance modeling. Each of the models is described in the context of these topics and characteristics to assess its purpose, approach, and level of detail. The issues are discussed in terms of the range of model capabilities available and summarized in tabular form for quick reference. The models are grouped into categories to illustrate their purposes and perspectives.

  2. Solar simulator for concentrator photovoltaic systems.

    PubMed

    Domínguez, César; Antón, Ignacio; Sala, Gabriel

    2008-09-15

    A solar simulator for measuring performance of large area concentrator photovoltaic (CPV) modules is presented. Its illumination system is based on a Xenon flash light and a large area collimator mirror, which simulates natural sun light. Quality requirements imposed by the CPV systems have been characterized: irradiance level and uniformity at the receiver, light collimation and spectral distribution. The simulator allows indoor fast and cost-effective performance characterization and classification of CPV systems at the production line as well as module rating carried out by laboratories.

  3. Studies of solar photovoltaic/electrolytic hydrogen systems

    NASA Astrophysics Data System (ADS)

    Ogden, Joan M.

    1992-12-01

    Hydrogen is a high quality, low polluting fuel, which could replace oil and natural gas for transportation, heating, and power generation. If hydrogen is generated via solar photovoltaic (PV) powered water electrolysis, it would be possible to produce and use energy on a large scale with essentially no greenhouse gas emission and very little local pollution. In previous studies, we investigated some of the implications of projected advances in thin film PV technologies for PV hydrogen production. Here we summarize our findings on the design and economics of PV hydrogen systems, and discuss potential long term applications of PV hydrogen as a transportation fuel for ``zero emissions'' fuel cell vehicles.

  4. Design considerations for lunar base photovoltaic power systems

    NASA Technical Reports Server (NTRS)

    Hickman, J. M.; Curtis, Henry B.; Landis, Geoffrey A.

    1990-01-01

    A survey was made of factors that may affect the design of photovoltaic arrays for a lunar base. These factors, which include the lunar environment and system design criteria, are examined. A photovoltaic power system design with a triangular array geometry is discussed and compared to a nuclear reactor power system and a power system utilizing both nuclear and solar power sources.

  5. Design considerations for lunar base photovoltaic power systems

    NASA Technical Reports Server (NTRS)

    Hickman, J. Mark; Curtis, Henry B.; Landis, Geoffrey A.

    1990-01-01

    A survey was made of factors that may affect the design of photovoltaic arrays for a lunar base. These factors, which include the lunar environment and system design criteria, are examined. A photovoltaic power system design with a triangular array geometry is discussed and compared to a nuclear reactor power systems and a power system utilizing both nuclear and solar power sources.

  6. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1983-01-01

    The analytical methodology for advanced encapsulation designs for the development of photovoltaic modules is presented. Analytical models are developed to test optical, thermal, electrical and structural properties of the various encapsulation systems. Model data is compared to relevant test data to improve model accuracy and develop general principles for the design of photovoltaic modules.

  7. Photovoltaic array mounting apparatus, systems, and methods

    DOEpatents

    West, Jack Raymond; Atchley, Brian; Hudson, Tyrus Hawkes; Johansen, Emil

    2016-01-05

    A photovoltaic array, including: (a) supports laid out on a surface in rows and columns; (b) photovoltaic modules positioned on top of the supports; and (c) fasteners connecting the photovoltaic modules to the supports, wherein the supports have an upper pedestal surface and a lower pedestal surface such that the photovoltaic modules are positioned at a non-horizontal angle when edges of the photovoltaic modules are positioned on top of the upper and lower pedestal surfaces, and wherein a portion of the fasteners rotate to lock the photovoltaic modules onto the supports.

  8. Photovoltaic array mounting apparatus, systems, and methods

    DOEpatents

    West, Jack Raymond; Atchley, Brian; Hudson, Tyrus Hawkes; Johansen, Emil

    2015-04-14

    A photovoltaic array, including: (a) supports laid out on a surface in rows and columns; (b) photovoltaic modules positioned on top of the supports; and (c) fasteners connecting the photovoltaic modules to the supports, wherein the supports have an upper pedestal surface and a lower pedestal surface such that the photovoltaic modules are positioned at a non-horizontal angle when edges of the photovoltaic modules are positioned on top of the upper and lower pedestal surfaces, and wherein a portion of the fasteners rotate to lock the photovoltaic modules onto the supports.

  9. Definition study for photovoltaic residential prototype system

    NASA Technical Reports Server (NTRS)

    Shepard, N. F.; Landes, R.; Kornrumpf, W. P.

    1976-01-01

    A site evaluation was performed to assess the relative merits of different regions of the country in terms of the suitability for experimental photovoltaic powered residences. Eight sites were selected based on evaluation criteria which included population, photovoltaic systems performance and the cost of electrical energy. A parametric sensitivity analysis was performed for four selected site locations. Analytical models were developed for four different power system implementation approaches. Using the model which represents a direct (or float) charge system implementation the performance sensitivity to the following parameter variations is reported: (1) solar roof slope angle; (2) ratio of the number of series cells in the solar array to the number of series cells in the lead-acid battery; and (3) battery size. For a Cleveland site location, a system with no on site energy storage and with a maximum power tracking inverter which feeds back excess power to the utility was shown to have 19 percent greater net system output than the second place system. The experiment test plan is described. The load control and data acquisition system and the data display panel for the residence are discussed.

  10. Characterization and Application of Colloidal Nanocrystalline Materials for Advanced Photovoltaics

    NASA Astrophysics Data System (ADS)

    Bhandari, Khagendra P.

    Solar energy is Earth's primary source of renewable energy and photovoltaic solar cells enable the direct conversion of sunlight into electricity. Crystalline silicon solar cells and modules have dominated photovoltaic technology from the beginning and they now constitute more than 90% of the PV market. Thin film (CdTe and CIGS) solar cells and modules come in second position in market share. Some organic, dye-sensitized and perovskite solar cells are emerging in the market but are not yet in full commercial scale. Solar cells made from colloidal nanocrystalline materials may eventually provide both low cost and high efficiency because of their promising properties such as high absorption coefficient, size tunable band gap, and quantum confinement effect. It is also expected that the greenhouse gas emission and energy payback time from nanocrystalline solar PV systems will also be least compared to all other types of PV systems mainly due to the least embodied energy throughout their life time. The two well-known junction architectures for the fabrication of quantum dot based photovoltaic devices are the Schottky junction and heterojunction. In Schottky junction cells, a heteropartner semiconducting material is not required. A low work function metal is used as the back contact, a transparent conducting layer is used as the front contact, and the layer of electronically-coupled quantum dots is placed between these two materials. Schottky junction solar cells explain the usefulness of nanocrystalline materials for high efficiency heterojunction solar cells. For heterojunction devices, n-type semiconducting materials such as ZnO , CdS or TiO2 have been used as suitable heteropartners. Here, PbS quantum dot solar cells were fabricated using ZnO and CdS semiconductor films as window layers. Both of the heteropartners are sputter-deposited onto TCO coated glass substrates; ZnO was deposited with the substrate held at room temperature and for CdS the substrate was at 250

  11. SUNRAYCE 93: Working safely with lead-acid batteries and photovoltaic power systems

    SciTech Connect

    DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M.

    1992-11-03

    The US Department of Energy (DOE) is sponsoring SUNRAYCE 93 to advance tile technology and use of photovoltaics and electric vehicles. Participants will use cars powered by photovoltaic modules and lead-acid storage batteries. This brochure, prepared for students and faculty participating in this race, outlines the health hazards presented by these electrical systems, and gives guidance on strategies for their safe usage. At the outset, it should be noted that working with photovoltaic systems and batteries requires electric vehicle drivers and technicians to have {open_quotes}hands-on{close_quotes} contact with the car on a daily basis. It is important that no one work near a photovoltaic energy system or battery, either in a vehicle or on the bench, unless they familiarize themselves with the components in use, and know and observe safe work practices including the safety precautions described in the manuals provided by the various equipment vendors and this document.

  12. SUNRAYCE 1993: Working safely with lead-acid batteries and photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Dephillips, M. P.; Moskowitz, P. D.; Fthenakis, V. M.

    1992-11-01

    The US Department of Energy (DOE) is sponsoring SUNRAYCE 93 to advance tile technology and use of photovoltaics and electric vehicles. Participants will use cars powered by photovoltaic modules and lead-acid storage batteries. This brochure, prepared for students and faculty participating in this race, outlines the health hazards presented by these electrical systems and gives guidance on strategies for their safe usage. At the outset, it should be noted that working with photovoltaic systems and batteries requires electric vehicle drivers and technicians to have 'hands-on' contact with the car on a daily basis. It is important that no one work near a photovoltaic energy system or battery, either in a vehicle or on the bench, unless they familiarize themselves with the components in use and know and observe safe work practices including the safety precautions described in the manuals provided by the various equipment vendors and this document.

  13. Advanced Technology Display House. Volume 2: Energy system design concepts

    NASA Technical Reports Server (NTRS)

    Maund, D. H.

    1981-01-01

    The preliminary design concept for the energy systems in the Advanced Technology Display House is analyzed. Residential energy demand, energy conservation, and energy concepts are included. Photovoltaic arrays and REDOX (reduction oxidation) sizes are discussed.

  14. Basics of the dimensioning and operations of photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Karl, H.

    1984-06-01

    Experiments and results in solar energy research are discussed. The characteristics of solar cells and photovoltaic generators are examined, and long-term experimental results on solar generators and hybrid collectors are reported. Photovoltaic systems are discussed, including battery systems, water pump systems, and hydrogen production by electrolysis.

  15. Microsystems Enabled Photovoltaics

    ScienceCinema

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

    2016-07-12

    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. Outreach and Education on Photovoltaic Systems

    NASA Astrophysics Data System (ADS)

    Lewis, Deanna; Brooks, Adria; Lonij, Vincent; Cronin, Alex

    2011-10-01

    Our photovoltaic (PV) outreach and education project is designed to promote understanding of PV technology through tours of PV facilities, experiential education, public lectures, and volunteer opportunities. In collaboration with Tucson Electric Power we give tours of an outdoor solar test yard. We organized Girl Scout camps thematic to solar power education, taught grade-school teachers about solar power curricula, started a non-profit organization for volunteer PV system installers, and served as mentors for the Tucson public schools' solar go-cart program. Examples of these outreach activities will be described.

  17. Data acquisition at a residential photovoltaic system

    NASA Astrophysics Data System (ADS)

    McIntyre, J. M.; Miller, G. N.

    A description is presented of the techniques employed for data collection and analysis in the study of a small residential photovoltaic (PV) system. A model home of approximately 139 sq m incorporated a PV array on the south-facing roof. The PV system was designed to interface directly to the local utility system through an inverter which converted the direct current output of the array to 60 Hz alternating current. Electric power could flow either from the utility lines into the house or vice versa. The solar panel consisted of 120 modules installed in a 5 x 24 array. Attention is given to initial problems, the conduction of a systems analysis, the data collection method, the equipment used in the data acquisition system, aspects of data collection, the encountered problems, and the results of the data acquisition project. It was found that the data acquisition system employed was effective for computer-compatible data collection.

  18. Tracking-integrated systems for concentrating photovoltaics

    NASA Astrophysics Data System (ADS)

    Apostoleris, Harry; Stefancich, Marco; Chiesa, Matteo

    2016-04-01

    Concentrating photovoltaic (CPV) systems, which use optical elements to focus light onto small-area solar cells, have the potential to minimize the costs, while improving efficiency, of photovoltaic technology. However, CPV is limited by the need to track the apparent motion of the Sun. This is typically accomplished using high-precision mechanical trackers that rotate the entire module to maintain normal light incidence. These machines are large, heavy and expensive to build and maintain, deterring commercial interest and excluding CPV from the residential market. To avoid this issue, some attention has recently been devoted to the development of tracking-integrated systems, in which tracking is performed inside the CPV module itself. This creates a compact system geometry that could be less expensive and more suitable for rooftop installation than existing CPV trackers. We review the basic tracking principles and concepts exploited in these systems, describe and categorize the existing designs, and discuss the potential impact of tracking integration on CPV cost models and commercial potential.

  19. Space Station Freedom advanced photovoltaics and battery technology development planning

    NASA Technical Reports Server (NTRS)

    Brender, Karen D.; Cox, Spruce M.; Gates, Mark T.; Verzwyvelt, Scott A.

    1993-01-01

    Space Station Freedom (SSF) usable electrical power is planned to be built up incrementally during assembly phase to a peak of 75 kW end-of-life (EOL) shortly after Permanently Manned Capability (PMC) is achieved in 1999. This power will be provided by planar silicon (Si) arrays and nickel-hydrogen (NiH2) batteries. The need for power is expected to grow from 75 kW to as much as 150 kW EOL during the evolutionary phase of SSF, with initial increases beginning as early as 2002. Providing this additional power with current technology may not be as cost effective as using advanced technology arrays and batteries expected to develop prior to this evolutionary phase. A six-month study sponsored by NASA Langley Research Center and conducted by Boeing Defense and Space Group was initiated in Aug. 1991. The purpose of the study was to prepare technology development plans for cost effective advanced photovoltaic (PV) and battery technologies with application to SSF growth, SSF upgrade after its arrays and batteries reach the end of their design lives, and other low Earth orbit (LEO) platforms. Study scope was limited to information available in the literature, informal industry contacts, and key representatives from NASA and Boeing involved in PV and battery research and development. Ten battery and 32 PV technologies were examined and their performance estimated for SSF application. Promising technologies were identified based on performance and development risk. Rough order of magnitude cost estimates were prepared for development, fabrication, launch, and operation. Roadmaps were generated describing key issues and development paths for maturing these technologies with focus on SSF application.

  20. Advanced power systems for EOS

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Weinberg, Irving; Flood, Dennis J.

    1991-01-01

    The Earth Observing System, which is part of the International Mission to Planet Earth, is NASA's main contribution to the Global Change Research Program. Five large platforms are to be launched into polar orbit: two by NASA, two by the European Space Agency, and one by the Japanese. In such an orbit the radiation resistance of indium phosphide solar cells combined with the potential of utilizing 5 micron cell structures yields an increase of 10 percent in the payload capability. If further combined with the Advanced Photovoltaic Solar Array, the total additional payload capability approaches 12 percent.

  1. Proceedings of the Flat-Plate Solar Array Project Research Forum on Photovoltaic Metallization Systems

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A photovoltaic Metallization Research forum, under the sponsorship of the Flat-Plate Solar Array Project consisted of five sessions, covering: (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques, and (5) future metallization challenges.

  2. A ten year review of performance of photovoltaic systems

    SciTech Connect

    Rosenthal, A.L.; Durand, S.J.; Thomas, M.G.

    1993-06-01

    This paper presents data compiled by the Photovoltaic Design Assistance Center at Sandia National Laboratories from more than eighty field tests performed at over thirty-five photovoltaic systems in the United States during the last ten years. The recorded performance histories, failure rates, and degradation of post-Block IV modules and balance-of-system (BOS) components are described in detail.

  3. Technical analysis of prospective photovoltaic systems in Utah.

    SciTech Connect

    Quiroz, Jimmy Edward; Cameron, Christopher P.

    2012-02-01

    This report explores the technical feasibility of prospective utility-scale photovoltaic system (PV) deployments in Utah. Sandia National Laboratories worked with Rocky Mountain Power (RMP), a division of PacifiCorp operating in Utah, to evaluate prospective 2-megawatt (MW) PV plants in different locations with respect to energy production and possible impact on the RMP system and customers. The study focused on 2-MW{sub AC} nameplate PV systems of different PV technologies and different tracking configurations. Technical feasibility was evaluated at three different potential locations in the RMP distribution system. An advanced distribution simulation tool was used to conduct detailed time-series analysis on each feeder and provide results on the impacts on voltage, demand, voltage regulation equipment operations, and flicker. Annual energy performance was estimated.

  4. Photovoltaic systems in remote locations: An experience summary

    NASA Astrophysics Data System (ADS)

    Ratajczak, A. F.

    1985-05-01

    Since 1979, the NASA Lewis Research Center has been responsible for the design, installation and operational support of 58 photovoltaic systems located in 27 countries. Together these systems contain 77.1 kW of photovoltaic modules and provide power for a variety of loads ranging from single low-power street light systems to a utility type power system for a village of over 150 people. Systems installation, reliability, operation, maintenance and repair experience is given and major problem areas are listed. Experience indicates that photovoltaic system technology is a proven technology, but that developing countries need to better posture themselves to acquire and utilize the technology. Recommendations are given.

  5. Laser and solar-photovoltaic space power systems comparison. II.

    NASA Technical Reports Server (NTRS)

    De Young, R. J.; Stripling, J.; Enderson, T. M.; Humes, D. H.; Davis, W. T.

    1984-01-01

    A comparison of total system cost is made between solar photovoltaic and laser/receiver systems. The laser systems assume either a solar-pumped CO2 blackbody transfer laser with MHD receiver or a solar pumped liquid neodymium laser with a photovoltaic receiver. Total system costs are less for the laser systems below 300 km where drag is significant. System costs are highly dependent on altitude.

  6. Photovoltaic energy systems: Design and installation

    NASA Astrophysics Data System (ADS)

    Buresch, M.

    The characteristics of solar radiation, the design of solar cells, and the installation of Si solar cell arrays for various applications are described. The discussion is limited to medium-scale photovoltaic systems, from 0.1-100 kW peak output, mounted in fixed flat plate modules, the simplest, most maintenance-free concept. Solar cell functioning principles are outlined, including the parasitic mechanisms which reduce cell efficiency. The magnitude, variations, and distribution of the global solar energy input are quantified. Consideration is given to series and parallel connected solar arrays, and to performance under a variable load. Array protection and failure detection are explored, as are integrated array power conditioning equipment comprising energy storage, voltage regulation, and ac to dc converters. Attention is also devoted to array mounting and matching solar cell systems to load.

  7. 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)

  8. Photovoltaic systems for Canadian prairie regions

    SciTech Connect

    Nigrin, J.

    1983-10-01

    The communications industry has a need for economic low power generators for their remote sites, with minimized power consumption. Photovoltaic generators (PV) promising hardware simplicity, low cost and low maintenance have the potential to fill this need. The operational record of PV generators is rather poor in harsh environment of the Canadian prairies. The authors' analysis of long term radiation data, field and laboratory tests show that often ignored cyclic winter radiation extremes and poor selection, operation and maintenance of batteries are the most frequent causes of PV system failures. They derive a reliable PV sizing curve for Edmonton (53/sup 0/N, 114/sup 0/W) and study various PV designs. At a cost of $20,000 per 100W a hybrid PV-TEG generator is shown to promise reliable operation which is not affected by extreme weather fluctuations of the Canadian prairies.

  9. Market valuation perspectives for photovoltaic systems

    SciTech Connect

    Klise, Geoffrey Taylor

    2014-08-01

    Sandia National Laboratories, working with Energy Sense Finance developed the proof-ofconcept PV Valueª tool in 2011 to provide real estate appraisers a tool that can be used to develop the market value and fair market value of a solar photovoltaic system. PV Valueª moved from a proof-of-concept spreadsheet to a commercial web-based tool developed and operated exclusively by Energy Sense Finance in June 2014. This paper presents the results of a survey aimed at different user categories in order to measure how the tool is being used in the marketplace as well as elicit information that can be used to improve the tools effectiveness.

  10. Photovoltaic system criteria documents. Volume 6: Criteria for auditing photovoltaic system applications and experiments. Revision A

    NASA Technical Reports Server (NTRS)

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

    1980-01-01

    The criteria is defined for auditing photovoltaic system applications and experiments. The purpose of the audit is twofold: to see if the application is meeting its stated objectives and to measure the application's progress in terms of the National Photovoltaic Program's goals of performance, cost, reliability, safety, and socio-environmental acceptance. The information obtained from an audit will be used to assess the status of an application and to provide the Department of Energy with recommendations on the future conduct of the application. Those aspects are covered of a site audit necessary to produce a systematic method for the gathering of qualitative and quantitative data to measure the success of an application. A sequence of audit events and guidelines for obtaining the required information is presented.

  11. Low Earth orbit durability evaluation of protected silicone for advanced refractive photovoltaic concentrator arrays

    NASA Technical Reports Server (NTRS)

    Degroh, Kim K.; Mccollum, Timothy A.

    1994-01-01

    The need for efficient, cost effective sources of electrical power in space has led to the development of photovoltaic power systems which make use of novel refractive solar concentrators. These concentrators have been conceived in both point-focus and linear-focus designs. Current concentrator lenses are fabricated from flexible silicones with Fresnel facets along their inside surface. To insure the efficient operation of these power systems, the concentrator lenses must be durable and the silicone material must remain specularly transmitting over a reasonable lifetime in low Earth orbit (LEO) and other space environments. Because of the vulnerability of silicones to atomic oxygen and ultraviolet radiation in LEO these lenses have been coated with a multi-layer metal oxide protective coating. The objective of this research was to evaluate the LEO durability of the multilayer coated silicone for advanced refractive photovoltaic concentrator arrays with respect to optical properties and microstructure. Flat metal oxide coated silicone samples were exposed to ground-laboratory and in-space atomic oxyqen for durability evaluation.

  12. Photovoltaic power systems and the National Electrical Code: Suggested practices

    SciTech Connect

    Wiles, J.

    1996-12-01

    This guide provides information on how the National Electrical Code (NEC) applies to photovoltaic systems. The guide is not intended to supplant or replace the NEC; it paraphrases the NEC where it pertains to photovoltaic systems and should be used with the full text of the NEC. Users of this guide should be thoroughly familiar with the NEC and know the engineering principles and hazards associated with electrical and photovoltaic power systems. The information in this guide is the best available at the time of publication and is believed to be technically accurate; it will be updated frequently. Application of this information and results obtained are the responsibility of the user.

  13. A sensitivity analysis of central flat-plate photovoltaic systems and implications for national photovoltaics program planning

    NASA Technical Reports Server (NTRS)

    Crosetti, M. R.

    1985-01-01

    The sensitivity of the National Photovoltaic Research Program goals to changes in individual photovoltaic system parameters is explored. Using the relationship between lifetime cost and system performance parameters, tests were made to see how overall photovoltaic system energy costs are affected by changes in the goals set for module cost and efficiency, system component costs and efficiencies, operation and maintenance costs, and indirect costs. The results are presented in tables and figures for easy reference.

  14. Investigation of the photovoltaic cell/ thermoelectric element hybrid system performance

    NASA Astrophysics Data System (ADS)

    Cotfas, D. T.; Cotfas, P. A.; Machidon, O. M.; Ciobanu, D.

    2016-06-01

    The PV/TEG hybrid system, consisting of the photovoltaic cells and thermoelectric element, is presented in the paper. The dependence of the PV/TEG hybrid system parameters on the illumination levels and the temperature is analysed. The maxim power values of the photovoltaic cell, of the thermoelectric element and of the PV/TEG system are calculated and a comparison between them is presented and analysed. An economic analysis is also presented.

  15. Photovoltaic (PV) Power Systems for Enhancing Energy Security

    DTIC Science & Technology

    2012-05-24

    Energy and Environment Technology Transition – Supporting DoD Readiness, Sustainability, and the Warfighter Photovoltaic (PV) Power Systems for...to 00-00-2012 4. TITLE AND SUBTITLE Photovoltaic (PV) Power Systems for Enhancing Energy Security 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c...use of 235W solar panels Note [2] System AC Rating based upon typical .77 conversion factor from DC power to AC power ConsiderationNo. PV LAYOUT OPTION

  16. Micro-concentrators for a microsystems-enabled photovoltaic system.

    PubMed

    Jared, Bradley H; Saavedra, Michael P; Anderson, Ben J; Goeke, Ron S; Sweatt, William C; Nielson, Gregory N; Okandan, Murat; Elisberg, Brenton; Snively, Dave; Duncan, John; Gu, Tian; Agrawal, Gautam; Haney, Michael W

    2014-03-10

    A 100X magnification, ± 2.5° field of view micro-concentrating optical system has been developed for a microsystems-enabled photovoltaic (MEPV) prototype module using 250 µm diameter multi-junction "stacked" PV cells.

  17. Photovoltaic Power Systems: A Tour Through the Alternatives

    ERIC Educational Resources Information Center

    Kelly, Henry

    1978-01-01

    Photovoltaic systems are examined as potentially major energy sources, along with the economic factors that will affect their future use. Cell design, power efficiency, and manufacturing problems are also considered. (MA)

  18. Photovoltaic system grounding and fault protection

    NASA Technical Reports Server (NTRS)

    Stolte, W. J.

    1983-01-01

    The grounding and fault protection aspects of large photovoltaic power systems are studied. Broadly, the overlapping functions of these two plant subsystems include providing for the safety of personnel and equipment. Grounding subsystem design is generaly governed by considerations of personnel safety and the limiting of hazardous voltages to which they are exposed during the occurrence of a fault or other misoperation of equipment. A ground system is designed to provide a safe path for fault currents. Metal portions of the modules, array structures, and array foundations are used as a part of the ground system, provided that they and their interconnection are designed to be suitably reliable over the life of the plant. Several alternative types of fault protection and detection equipment are designed into the source circuits and dc buses feeding the input terminals of the subfield power conditioner. This design process requires evaluation of plausible faults, equipment, and remedial actions planned to correct faults. The evaluation should also consider life cycle cost impacts.

  19. Advanced Power Electronic Interfaces for Distributed Energy Systems Part 1: Systems and Topologies

    SciTech Connect

    Kramer, W.; Chakraborty, S.; Kroposki, B.; Thomas, H.

    2008-03-01

    This report summarizes power electronic interfaces for DE applications and the topologies needed for advanced power electronic interfaces. It focuses on photovoltaic, wind, microturbine, fuel cell, internal combustion engine, battery storage, and flywheel storage systems.

  20. Mains-connected photovoltaic system for a house

    NASA Astrophysics Data System (ADS)

    Schmid, J.; Goetzberger, A.

    1983-09-01

    Tests were conducted on a residence equipped with mains photovoltaic electric energy supply system to assess components under realistic conditions, to determine installation effort, and to find solutions for integration of solar cells in house roofs. The technical design of the photovoltaic system is described. When solar radiation is high the solar cells cover a considerable part of the energy consumption and deliver superfluous energy to the mains. The mains supplies energy in case of low radiation.

  1. Maintenance of Photovoltaic Power Systems. Revision 1.

    DTIC Science & Technology

    1985-06-01

    superstrate (usually tempered glass), an encapsulant, photovoltaic cells, and a substrate laminated together under pressure and temperature. The lamination...STRUCTURAL SURSTRATE METAL SEALING GASKET INTrRCONNECTS CELL FRAME TAPE T A P ET R A N P A R E N T S T R U C T U R A L SUPERSTRATE _,, TRANSPARENT...ENCAPSULANT SUPERSTRATE X - MODULE - OPAQUE ENCAPSULANT 1 17- B SACK COVER FIGURE 2-7. Typical Photovoltaic Module Construction. 2.4.3 Electrical

  2. Definition study for photovoltaic residential prototype system

    NASA Technical Reports Server (NTRS)

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

    1976-01-01

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

  3. 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.

  4. Grid-Tied Photovoltaic Power System

    NASA Technical Reports Server (NTRS)

    Eichenberg, Dennis J.

    2011-01-01

    A grid-tied photovoltaic (PV) power 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. Operating costs of a PV power system are low compared to conventional power technologies. This method can displace the highest-cost electricity during times of peak demand in most climatic regions, and thus reduce grid loading. Net metering is often used, in which independent power producers such as PV power systems are connected to the utility grid via the customers main service panels and meters. When the PV power system is generating more power than required at that location, the excess power is provided to the utility grid. The customer pays the net of the power purchased when the on-site power demand is greater than the onsite power production, and the excess power is returned to the utility grid. Power generated by the PV system reduces utility demand, and the surplus power aids the community. Modern PV panels are readily available, reliable, efficient, and economical, with a life expectancy of at least 25 years. Modern electronics have been the enabling technology behind grid-tied power systems, making them safe, reliable, efficient, and economical with a life expectancy equal to the modern PV panels. The grid-tied PV power system was successfully designed and developed, and this served to validate the basic principles developed, and the theoretical work that was performed. Grid-tied PV power systems are reliable, maintenance- free, long-life power systems, and are of significant value to NASA and the community. Of particular value are the analytical tools and capabilities that have been successfully developed. Performance predictions can be made confidently for grid-tied PV systems of various scales. The work was done under the NASA Hybrid Power Management (HPM

  5. The 1987 Photovoltaics Annual Systems Symposium: Agenda and abstracts

    NASA Astrophysics Data System (ADS)

    Chapman, R. N.

    1987-02-01

    The 1987 Photovoltaic Annual Systems Symposium (PASS'87) is being held at La Mansion Hotel, February 18, 19, and 20, 1987, in Austin, Texas. The meeting is sponsored by Sandia National Laboratories, the US Department of Energy, and the City of Austin Electric Utility Department. This document contains a summary of the findings from PASS'86, the agenda for PASS'87, and extended abstracts describing the PASS'87 presentations. The technical program is divided into five sessions: Department of Energy Program Directions, National and State Photovoltaic Activities, Subsystem Technology, Utility Interface Issues, and Stand-Alone Systems. A panel discussion scheduled for the afternoon of the 19th will focus on the utilities' perception of photovoltaics. A tour of Austin's 300 kW Solar Photovoltaic Test Facility is available to those attending the symposium.

  6. 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.

  7. Installation of a Roof Mounted Photovoltaic System

    NASA Astrophysics Data System (ADS)

    Lam, M.

    2015-12-01

    In order to create a safe and comfortable environment for students to learn, a lot of electricity, which is generated from coal fired power plants, is used. Therefore, ISF Academy, a school in Hong Kong with approximately 1,500 students, will be installing a rooftop photovoltaic (PV) system with 302 solar panels. Not only will these panels be used to power a classroom, they will also serve as an educational opportunity for students to learn about the importance of renewable energy technology and its uses. There were four different options for the installation of the solar panels, and the final choice was made based on the loading capacity of the roof, considering the fact that overstressing the roof could prove to be a safety hazard. Moreover, due to consideration of the risk of typhoons in Hong Kong, the solar panel PV system will include concrete plinths as counterweights - but not so much that the roof would be severely overstressed. During and after the installation of the PV system, students involved would be able to do multiple calculations, such as determining the reduction of the school's carbon footprint. This can allow students to learn about the impact renewable energy can have on the environment. Another project students can participate in includes measuring the efficiency of the solar panels and how much power can be produced per year, which in turn can help with calculate the amount of money saved per year and when we will achieve economic parity. In short, the installation of the roof mounted PV system will not only be able to help save money for the school but also provide learning opportunities for students studying at the ISF Academy.

  8. Photovoltaic system criteria documents. Volume 3: Environmental issues and evaluation criteria for photovoltaic applications

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    The environmental issues and evaluation criteria relating to the suitability of sites proposed for photovoltaic (PV) system deployment are identified. The important issues are defined, briefly discussed and then developed into evaluation criteria. System designers are provided with information on the environmental sensitivity of PV systems in realistic applications, background material which indicates the applicability of the siting issues identified, and evaluation criteria are defined to facilitate the selection of sites that maximize PV system operation.

  9. Market and economic analysis of residential photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Tabors, R. D.

    1982-06-01

    The overall structure of a project to evaluate the U.S. residential photovoltaic market or markets is reviewed and experience obtained before cuts in federal funding for the project were reduced is summarized. Topics covered include residential worth analysis, (including retrofit applications); evaluation of presently available regional, econometric models which could be used to project housing stocks; and the analysis of retrofit potential for residential photovoltaic power systems given available roof area.

  10. Energy and environmental analysis of a linear concentrating photovoltaic system

    NASA Astrophysics Data System (ADS)

    Kerzmann, Tony

    The world is facing an imminent energy supply crisis. In order to sustain and increase our energy supply in an environmentally-conscious manner, it is necessary to advance renewable technologies. Despite this urgency, however, it is paramount to consider the larger environmental effects associated with using renewable energy resources. This research is meant to better understand linear concentrating photovoltaics (LCPVs) from an engineering and environmental standpoint. In order to analyze the LCPV system, a simulation and life cycle assessment (LCA) were developed. The LCPV system serves two major purposes: it produces electricity, and waste heat is collected for heating use. There are three parts to the LCPV simulation. The first part simulates the multijunction cell output so as to calculate the temperature-dependent electricity generation. The second part simulates the cell cooling and waste heat recovery system using a model consisting of heat transfer and fluid flow equations. The waste heat recovery in the LCPV system was linked to a hot water storage system, which was also modeled. Coupling the waste heat recovery simulation and the hot water storage system gives an overall integrated system that is useful for system design, optimization, and acts as a stepping stone for future multijunction cell Photovoltaic/Thermal (PV/T) systems. Finally, all of the LCPV system components were coded in Engineering Equation Solver (EES) and were used in an energy analysis under actual weather and solar conditions for the Phoenix, AZ, region. The life cycle assessment for the LCPV system allowed for an environmental analysis of the system where areas of the highest environmental impact were pinpointed. While conducting the LCA research, each component of the system was analyzed from a resource extraction, production, and use standpoint. The collective production processes of each LCPV system component were gathered into a single inventory of materials and energy flows

  11. Photovoltaic/diesel hybrid systems: The design process

    NASA Astrophysics Data System (ADS)

    Jones, G. J.; Chapman, R. N.

    A photovoltaic/storage system by itself may be uneconomical for stand-alone applications with large energy demands. However, by combining the PV system with a back-up energy source, such as a diesel, gasoline, or propane/thermoelectric generator, system economics can be improved. Such PV/fossil hybrid systems are being used, but their design has required detailed modeling to determine the optimal mix of photovoltaics and back-up energy. Recent data on diesel field reliability and a new design technique for stand-alone systems have overcome this problem. The approach provides the means for sizing the photovoltaic system to obtain a near optimal hybrid system, with about a 90% savings in back-up fuel costs. System economics are determined by comparing PV capital cost to the present value of the displaced diesel operation and maintenance costs.

  12. Simulation and simplified design studies of photovoltaic systems

    SciTech Connect

    Evans, D.L.; Facinelli, W.A.; Koehler, L.P.

    1980-09-01

    Results of TRNSYS simulations of photovoltaic systems with electrical storage are described. Studies of the sensitivity of system performance, in terms of the fraction of the electrical load supplied by the solar energy system, to variables such as array size, battery size, location, time of year, and load shape are reported. An accurate simplified method for predicting array output of max-power photovoltaic systems is presented. A second simplified method, which estimates the overall performance of max-power systems, is developed. Finally, a preliminary technique for predicting clamped-voltage system performance is discussed.

  13. Proceedings of the flat-plate solar array project research forum on photovoltaic metallization systems

    SciTech Connect

    1983-11-15

    A Photovoltaic Metallization Research Forum, under the sponsorship of the Jet Propulsion Laboratory's Flat-Plate Solar Array Project and the US Department of Energy, was held March 16-18, 1983 at Pine Mountain, Georgia. The Forum consisted of five sessions, covering (1) the current status of metallization systems, (2) system design, (3) thick-film metallization, (4) advanced techniques and (5) future metallization challenges. Twenty-three papers were presented.

  14. Photovoltaic power systems for rural areas of developing countries

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.; Bifano, W. J.; Hein, G. F.; Ratajczak, A. F.

    1979-01-01

    Photovoltaic (PV) applications for rural areas of underdeveloped countries are discussed in relation to PV system technology, reliability, and present and projected cost. The information presented is derived mainly from NASA, Lewis Research Center experience with PV systems deployed with a variety of users for applications relevant to LDCs. A detailed description of two village power systems is included. Energy cost comparisons are presented for PV systems versus alternative energy sources. It is concluded, based on present PV system technology, reliability and cost that photovoltaics provides a realistic energy option for LDCs in both the near- and far-term.

  15. Sliding mode controller for a photovoltaic pumping system

    NASA Astrophysics Data System (ADS)

    ElOugli, A.; Miqoi, S.; Boutouba, M.; Tidhaf, B.

    2017-03-01

    In this paper, a sliding mode control scheme (SMC) for maximum power point tracking controller for a photovoltaic pumping system, is proposed. The main goal is to maximize the flow rate for a water pump, by forcing the photovoltaic system to operate in its MPP, to obtain the maximum power that a PV system can deliver.And this, through the intermediary of a sliding mode controller to track and control the MPP by overcoming the power oscillation around the operating point, which appears in most implemented MPPT techniques. The sliding mode control approach is recognized as one of the efficient and powerful tools for nonlinear systems under uncertainty conditions.The proposed controller with photovoltaic pumping system is designed and simulated using MATLAB/SIMULINK environment. In addition, to evaluate its performances, a classical MPPT algorithm using perturb and observe (P&O) has been used for the same system to compare to our controller. Simulation results are shown.

  16. Performance model assessment for multi-junction concentrating photovoltaic systems.

    SciTech Connect

    Stein, Joshua S.; Riley, Daniel M.; McConnell, Robert.; Sahm, Aaron; Crawford, Clark; King, David L.; Cameron, Christopher P.; Foresi, James S.

    2010-03-01

    Four approaches to modeling multi-junction concentrating photovoltaic system performance are assessed by comparing modeled performance to measured performance. Measured weather, irradiance, and system performance data were collected on two systems over a one month period. Residual analysis is used to assess the models and to identify opportunities for model improvement. Large photovoltaic systems are typically developed as projects which supply electricity to a utility and are owned by independent power producers. Obtaining financing at favorable rates and attracting investors requires confidence in the projected energy yield from the plant. In this paper, various performance models for projecting annual energy yield from Concentrating Photovoltaic (CPV) systems are assessed by comparing measured system output to model predictions based on measured weather and irradiance data. The results are statistically analyzed to identify systematic error sources.

  17. High-resolution global irradiance monitoring from photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Buchmann, Tina; Pfeilsticker, Klaus; Siegmund, Alexander; Meilinger, Stefanie; Mayer, Bernhard; Pinitz, Sven; Steinbrecht, Wolfgang

    2016-04-01

    Reliable and regional differentiated power forecasts are required to guarantee an efficient and economic energy transition towards renewable energies. Amongst other renewable energy technologies, e.g. wind mills, photovoltaic systems are an essential component of this transition being cost-efficient and simply to install. Reliable power forecasts are however required for a grid integration of photovoltaic systems, which among other data requires high-resolution spatio-temporal global irradiance data. Hence the generation of robust reviewed global irradiance data is an essential contribution for the energy transition. To achieve this goal our studies introduce a novel method which makes use of photovoltaic power generation in order to infer global irradiance. The method allows to determine high-resolution temporal global irradiance data (one data point every 15 minutes at each location) from power data of operated photovoltaic systems. Due to the multitude of installed photovoltaic systems (in Germany) the detailed spatial coverage is much better than for example only using global irradiance data from conventional pyranometer networks (e.g. from the German Weather Service). Our designated method is composed of two components: a forward component, i.e. to conclude from predicted global irradiance to photovoltaic (PV) power, and a backward component, i.e. from PV power with suitable calibration to global irradiance. The forward process is modelled by using the radiation transport model libRadtran (B. Mayer and A. Kylling (1)) for clear skies to obtain the characteristics (orientation, size, temperature dependence, …) of individual PV systems. For PV systems in the vicinity of a meteorological station, these data are validated against calibrated pyranometer readings. The forward-modelled global irradiance is used to determine the power efficiency for each photovoltaic system using non-linear optimisation techniques. The backward component uses the power efficiency

  18. Detailed Performance Model for Photovoltaic Systems: Preprint

    SciTech Connect

    Tian, H.; Mancilla-David, F.; Ellis, K.; Muljadi, E.; Jenkins, P.

    2012-07-01

    This paper presents a modified current-voltage relationship for the single diode model. The single-diode model has been derived from the well-known equivalent circuit for a single photovoltaic cell. The modification presented in this paper accounts for both parallel and series connections in an array.

  19. Self-deploying photovoltaic power system

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J. (Inventor)

    1993-01-01

    A lightweight flexible photovoltaic (PV) blanket is attached to a support structure of initially stowed telescoping members. The deployment mechanism comprises a series of extendable and rotatable columns. As these columns are extended the PV blanket is deployed to its proper configuration.

  20. Solar photovoltaic power system for a radio station

    SciTech Connect

    Nichols, B. E.

    1980-12-01

    Under sponsorship of the US Department of Energy, Massachusetts Institute of Technology Lincoln Laboratory has developed a concept for a small photovoltaic power system. Of simple construction, the system uses low-cost, prefabricated, transportable units for easy, fast installation and requires minimal site preparation. The first application of this experimental system began operation in August 1979 at daytime AM radio station WNBO in Bryan, Ohio. The project was jointly undertaken by the Laboratory and the radio station. The photovoltaic system described holds promise for a wide range of applications and economic feasibility by the mid- to late-1980s.

  1. Development and testing of advanced fire-resistant photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Sugimura, R. S.; Otth, D. H.; Ross, R. G., Jr.

    The evaluation of back-surface materials flammability in order to identify fire resistant module designs is examined. The fire test apparatus, burning-brand test sequence, and spread-of-flame test sequence are described. Video recordings and time-temperature profiles of module back surfaces are utilized to study the flammability failure mechanism and identify high-temperature materials. A table of flammability test results for various module designs is provided. The data reveals that 2-mil kapton, fiberglass cloth coated or impregnated with a material to plug pores, and metal foil back-surface materials achieve class A and B fire-resistance levels, and are applicable for photovoltaic module designs.

  2. ERDA/Lewis research center photovoltaic systems test facility

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Johnson, J. A.; Knapp, W. D.; Rigo, H.; Stover, J.; Suhay, R.

    1977-01-01

    A national photovoltaic power systems test facility (of initial 10-kW peak power rating) is described. It consists of a solar array to generate electrical power, test-hardware for several alternate methods of power conversion, electrical energy storage systems, and an instrumentation and data acquisition system.

  3. Simulation of thermal aspects of residential photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Hart, G. W.; Raghuraman, P.

    1982-06-01

    A program was developed to simulate the performance of utility interactive residential photovoltaic (PV) energy systems. The PV system is divided into its major functional components, which are individually described with computer models. These models are described in detail. The results of simulation and actual measured data are compared. The thermal influences on the design of such PV energy systems are given particular attention.

  4. Performance of a photovoltaically powered air-conditioning system

    SciTech Connect

    Kern, Jr, E. C.; Millner, A. R.

    1980-01-01

    A vapor-compression air conditioner coupled directly to a photovoltaic array is discussed. Previous analyses of such a system are reviewed, and a development system designed to test the concept is described. Preliminary experiments indicate that the performance of this initial system falls considerably short of analytic expectations.

  5. Performance model assessment for multi-junction concentrating photovoltaic systems.

    SciTech Connect

    Riley, Daniel M.; McConnell, Robert.; Sahm, Aaron; Crawford, Clark; King, David L.; Cameron, Christopher P.; Foresi, James S.

    2010-03-01

    Four approaches to modeling multi-junction concentrating photovoltaic system performance are assessed by comparing modeled performance to measured performance. Measured weather, irradiance, and system performance data were collected on two systems over a one month period. Residual analysis is used to assess the models and to identify opportunities for model improvement.

  6. 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.

  7. Analysis of batteries for use in photovoltaic systems. Final report

    SciTech Connect

    Podder, A; Kapner, M

    1981-02-01

    An evaluation of 11 types of secondary batteries for energy storage in photovoltaic electric power systems is given. The evaluation was based on six specific application scenarios which were selected to represent the diverse requirements of various photovoltaic systems. Electrical load characteristics and solar insulation data were first obtained for each application scenario. A computer-based simulation program, SOLSIM, was then developed to determine optimal sizes for battery, solar array, and power conditioning systems. Projected service lives and battery costs were used to estimate life-cycle costs for each candidate battery type. The evaluation considered battery life-cycle cost, safety and health effects associated with battery operation, and reliability/maintainability. The 11 battery types were: lead-acid, nickel-zinc, nickel-iron, nickel-hydrogen, lithium-iron sulfide, calcium-iron sulfide, sodium-sulfur, zinc-chlorine, zinc-bromine, Redox, and zinc-ferricyanide. The six application scenarios were: (1) a single-family house in Denver, Colorado (photovoltaic system connected to the utility line); (2) a remote village in equatorial Africa (stand-alone power system); (3) a dairy farm in Howard County, Maryland (onsite generator for backup power); (4) a 50,000 square foot office building in Washington, DC (onsite generator backup); (5) a community in central Arizona with a population of 10,000 (battery to be used for dedicated energy storage for a utility grid-connected photovoltaic power plant); and (6) a military field telephone office with a constant 300 W load (trailer-mounted auxiliary generator backup). Recommendations for a research and development program on battery energy storage for photovoltaic applications are given, and a discussion of electrical interfacing problems for utility line-connected photovoltaic power systems is included. (WHK)

  8. 75 FR 53277 - Notice of Workshop on Polymers for Photovoltaic Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... National Institute of Standards and Technology Notice of Workshop on Polymers for Photovoltaic Systems.... SUMMARY: The National Institute of Standards and Technology announces a ] Workshop on Polymers for... polymeric materials used in photovoltaic systems; testing, performance, and reliability of polymers...

  9. Task V of the IEA Photovoltaic Power Systems Program: Implementing Accomplishments and Activities

    SciTech Connect

    Bower, Ward

    1999-06-10

    The International Energy Agency (IEA) is an energy forum for 24 industrialized countries and was established in 1974 as an autonomous body within the Organization for Economic Cooperation and Development (OECD). The IEA Photovoltaic Power Systems (PVPS) program implementing agreement was signed in 1993, and renewed for another five years in 1998. Twenty-two countries are collaborating under the auspices of the IEA in the PVPS to address common technical and informational barriers that often limit the rate at which photovoltaic technologies advance into the markets. Task V of the IEA PVPS is entitled "Grid Interconnection of Building-Integrated and Other Dispersed Photovoltaic Power Systems." The task sponsored a workshop in September 1997 on grid-interconnection of photovoltaic systems and is planning a second workshop to address impacts of more penetration of dispersed systems into the utility grid. This paper will summarize the accomplishments of Task V over the last five years and will detail the planned work for the next three years.

  10. Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Presentation)

    SciTech Connect

    Miller, D. C.; Muller, M.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

    2011-04-01

    Presented at the 7th International Conference on Concentrating Photovoltaic Systems (CPV-7), 4-6 April 2011, Las Vegas, Nevada. Many concentrating photovoltaic (CPV) systems use a polymeric encapsulant to couple an optical component and/or coverglass to the cell. In that location, the encapsulation improves the transmission of concentrated optical flux through interfaces(s) while protecting the cell from the environment. The durability of encapsulation materials, however, is not well established relative to the desired service life of 30 years. Therefore, we have initiated a screen test to identify the field-induced failure modes for a variety of popular PV encapsulation materials.

  11. Systems and applications analysis for concentrating photovoltaic-thermal systems

    NASA Astrophysics Data System (ADS)

    Schwinkendorf, W. E.

    Numerical simulations were carried out of the performance, costs, and land use requirements of five commercial and six residential applications of combined photovoltaic-thermal (PVT) power plants. Line focus Fresnel concentrators (LFF) systems were selected after a simulated comparison of different PVT systems. Load profiles were configured from industrial data and ASHRAE and building codes. Assumptions included costs of $1/Wp, 0.15 efficiency, and a cost of $275/sq m, as well as a 25 percent solar tax credit. The calculations showed that a significant low temperature thermal load must be available, but no heat recovery system. Industrial situations were identified which favor solar thermal energy alone rather than a combined system. The thermal energy displacement was determined to be the critical factor in assessing the economics of the PVT systems.

  12. Controlling of grid connected photovoltaic lighting system with fuzzy logic

    SciTech Connect

    Saglam, Safak; Ekren, Nazmi; Erdal, Hasan

    2010-02-15

    In this study, DC electrical energy produced by photovoltaic panels is converted to AC electrical energy and an indoor area is illuminated using this energy. System is controlled by fuzzy logic algorithm controller designed with 16 rules. Energy is supplied from accumulator which is charged by photovoltaic panels if its energy would be sufficient otherwise it is supplied from grid. During the 1-week usage period at the semester time, 1.968 kWh energy is used from grid but designed system used 0.542 kWh energy from photovoltaic panels at the experiments. Energy saving is determined by calculations and measurements for one education year period (9 months) 70.848 kWh. (author)

  13. Advancing the Deployment of Utility-Scale Photovoltaic Plants in the Northeast

    SciTech Connect

    Lofaro R.; Villaran, M; Colli, A.

    2012-06-03

    As one of the premier research laboratories operated by the Department of Energy, Brookhaven National Laboratory (BNL) is pursuing an energy research agenda that focuses on renewable energy systems and will help to secure the nation's energy security. A key element of the BNL research is the advancement of grid-connected utility-scale solar photovoltaic (PV) plants, particularly in the northeastern part of the country where BNL is located. While a great deal of information has been generated regarding solar PV systems located in mostly sunny, hot, arid climates of the southwest US, very little data is available to characterize the performance of these systems in the cool, humid, frequently overcast climates experienced in the northeastern portion of the country. Recognizing that there is both a need and a market for solar PV generation in the northeast, BNL is pursuing research that will advance the deployment of this important renewable energy resource. BNL's research will leverage access to unique time-resolved data sets from the 37MWp solar array recently developed on its campus. In addition, BNL is developing a separate 1MWp solar research array on its campus that will allow field testing of new PV system technologies, including solar modules and balance of plant equipment, such as inverters, energy storage devices, and control platforms. These research capabilities will form the cornerstone of the new Northeast Solar Energy Research Center (NSERC) being developed at BNL. In this paper, an overview of BNL's energy research agenda is given, along with a description of the 37MWp solar array and the NSERC.

  14. 75 FR 61509 - Notice of Issuance of Final Determination Concerning Solar Photovoltaic Panel Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-05

    ... country of origin of the solar photovoltaic systems for purposes of U.S. Government procurement. DATES... of origin of certain solar photovoltaic systems which may be offered to the United States Government..., Trade Agreements Act of 1979; Country of Origin of solar photovoltaic panel system;...

  15. Advances in polycrystalline thin-film photovoltaics for space applications

    SciTech Connect

    Lanning, B.R.; Armstrong, J.H.; Misra, M.S.

    1994-09-01

    Polycrystalline, thin-film photovoltaics represent one of the few (if not the only) renewable power sources which has the potential to satisfy the demanding technical requirements for future space applications. The demand in space is for deployable, flexible arrays with high power-to-weight ratios and long-term stability (15-20 years). In addition, there is also the demand that these arrays be produced by scalable, low-cost, high yield, processes. An approach to significantly reduce costs and increase reliability is to interconnect individual cells series via monolithic integration. Both CIS and CdTe semiconductor films are optimum absorber materials for thin-film n-p heterojunction solar cells, having band gaps between 0.9-1.5 eV and demonstrated small area efficiencies, with cadmium sulfide window layers, above 16.5 percent. Both CIS and CdTe polycrystalline thin-film cells have been produced on a laboratory scale by a variety of physical and chemical deposition methods, including evaporation, sputtering, and electrodeposition. Translating laboratory processes which yield these high efficiency, small area cells into the design of a manufacturing process capable of producing 1-sq ft modules, however, requires a quantitative understanding of each individual step in the process and its effect on overall module performance. With a proper quantification and understanding of material transport and reactivity for each individual step, manufacturing process can be designed that is not `reactor-specific` and can be controlled intelligently with the design parameters of the process. The objective of this paper is to present an overview of the current efforts at MMC to develop large-scale manufacturing processes for both CIS and CdTe thin-film polycrystalline modules. CIS cells/modules are fabricated in a `substrate configuration` by physical vapor deposition techniques and CdTe cells/modules are fabricated in a `superstrate configuration` by wet chemical methods.

  16. 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.

  17. Laser photovoltaic power system synergy for SEI applications

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey A.; Hickman, J. M.

    1991-01-01

    Solar arrays can provide reliable space power, but do not operate when there is no solar energy. Photovoltaic arrays can also convert laser energy with high efficiency. One proposal to reduce the required mass of energy storage required is to illuminate the photovoltaic arrays by a ground laser system. It is proposed to locate large lasers on cloud-free sites at one or more ground locations, and use large lenses or mirrors with adaptive optical correction to reduce the beam spread due to diffraction or atmospheric turbulence. During the eclipse periods or lunar night, the lasers illuminate the solar arrays to a level sufficient to provide operating power.

  18. Decentralized Optimal Dispatch of Photovoltaic Inverters in Residential Distribution Systems

    SciTech Connect

    Dall'Anese, Emiliano; Dhople, Sairaj V.; Johnson, Brian B.; Giannakis, Georgios B.

    2015-10-05

    Summary form only given. Decentralized methods for computing optimal real and reactive power setpoints for residential photovoltaic (PV) inverters are developed in this paper. It is known that conventional PV inverter controllers, which are designed to extract maximum power at unity power factor, cannot address secondary performance objectives such as voltage regulation and network loss minimization. Optimal power flow techniques can be utilized to select which inverters will provide ancillary services, and to compute their optimal real and reactive power setpoints according to well-defined performance criteria and economic objectives. Leveraging advances in sparsity-promoting regularization techniques and semidefinite relaxation, this paper shows how such problems can be solved with reduced computational burden and optimality guarantees. To enable large-scale implementation, a novel algorithmic framework is introduced - based on the so-called alternating direction method of multipliers - by which optimal power flow-type problems in this setting can be systematically decomposed into sub-problems that can be solved in a decentralized fashion by the utility and customer-owned PV systems with limited exchanges of information. Since the computational burden is shared among multiple devices and the requirement of all-to-all communication can be circumvented, the proposed optimization approach scales favorably to large distribution networks.

  19. Advances in polycrystalline thin-film photovoltaics for space applications

    NASA Astrophysics Data System (ADS)

    Lanning, Bruce R.; Armstrong, Joseph H.; Misra, Mohan S.

    1994-09-01

    Polycrystalline, thin-film photovoltaics represent one of the few (if not the only) renewable power sources which has the potential to satisfy the demanding technical requirements for future space applications. The demand in space is for deployable, flexible arrays with high power-to-weight ratios and long-term stability (15-20 years). In addition, there is also the demand that these arrays be produced by scalable, low-cost, high yield, processes. An approach to significantly reduce costs and increase reliability is to interconnect individual cells series via monolithic integration. Both CIS and CdTe semiconductor films are optimum absorber materials for thin-film n-p heterojunction solar cells, having band gaps between 0.9-1.5 ev and demonstrated small area efficiencies, with cadmium sulfide window layers, above 16.5 percent. Both CIS and CdTe polycrystalline thin-film cells have been produced on a laboratory scale by a variety of physical and chemical deposition methods, including evaporation, sputtering, and electrodeposition. Translating laboratory processes which yield these high efficiency, small area cells into the design of a manufacturing process capable of producing 1-sq ft modules, however, requires a quantitative understanding of each individual step in the process and its (each step) effect on overall module performance. With a proper quantification and understanding of material transport and reactivity for each individual step, manufacturing process can be designed that is not 'reactor-specific' and can be controlled intelligently with the design parameters of the process. The objective of this paper is to present an overview of the current efforts at MMC to develop large-scale manufacturing processes for both CIS and CdTe thin-film polycrystalline modules. CIS cells/modules are fabricated in a 'substrate configuration' by physical vapor deposition techniques and CdTe cells/modules are fabricated in a 'superstrate configuration' by wet chemical

  20. Advances in polycrystalline thin-film photovoltaics for space applications

    NASA Technical Reports Server (NTRS)

    Lanning, Bruce R.; Armstrong, Joseph H.; Misra, Mohan S.

    1994-01-01

    Polycrystalline, thin-film photovoltaics represent one of the few (if not the only) renewable power sources which has the potential to satisfy the demanding technical requirements for future space applications. The demand in space is for deployable, flexible arrays with high power-to-weight ratios and long-term stability (15-20 years). In addition, there is also the demand that these arrays be produced by scalable, low-cost, high yield, processes. An approach to significantly reduce costs and increase reliability is to interconnect individual cells series via monolithic integration. Both CIS and CdTe semiconductor films are optimum absorber materials for thin-film n-p heterojunction solar cells, having band gaps between 0.9-1.5 ev and demonstrated small area efficiencies, with cadmium sulfide window layers, above 16.5 percent. Both CIS and CdTe polycrystalline thin-film cells have been produced on a laboratory scale by a variety of physical and chemical deposition methods, including evaporation, sputtering, and electrodeposition. Translating laboratory processes which yield these high efficiency, small area cells into the design of a manufacturing process capable of producing 1-sq ft modules, however, requires a quantitative understanding of each individual step in the process and its (each step) effect on overall module performance. With a proper quantification and understanding of material transport and reactivity for each individual step, manufacturing process can be designed that is not 'reactor-specific' and can be controlled intelligently with the design parameters of the process. The objective of this paper is to present an overview of the current efforts at MMC to develop large-scale manufacturing processes for both CIS and CdTe thin-film polycrystalline modules. CIS cells/modules are fabricated in a 'substrate configuration' by physical vapor deposition techniques and CdTe cells/modules are fabricated in a 'superstrate configuration' by wet chemical

  1. Solar photovoltaic applications seminar: design, installation and operation of small, stand-alone photovoltaic power systems

    SciTech Connect

    Not Available

    1980-07-01

    This seminar material was developed primarily to provide solar photovoltaic (PV) applied engineering technology to the Federal community. An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. The seminar details general systems design and incorporates most known information from industry, academia, and Government concerning small solar cell power system design engineering, presented in a practical and applied manner. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping, domestic uses, navigational and aircraft aids, and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand-alone systems to be used in remote locations. Also presented are practical lessons gained from currently installed and operating systems, problems at sites and their resolution, a logical progression through each major phase of system acquisition, as well as thorough design reviews for each application.

  2. EMISSIONS REDUCTION DATA FOR GRID-CONNECTED PHOTOVOLTAIC POWER SYSTEMS

    EPA Science Inventory

    This study measured the pollutant emission reduction potential of 29 photovoltaic (PV) systems installed on residential and commercial building rooftops across the U.S. from 1993 through 1997. The U.S. Environmental Protection Agency (EPA) and 21 electric power companies sponsor...

  3. Photovoltaic power system considerations for future lunar bases

    NASA Technical Reports Server (NTRS)

    Flood, Dennis J.; Appelbaum, Joseph

    1989-01-01

    The cost of transportation to the lunar surface places a premium on developing ultralightweight power system technology to support the eventual establishment of a lunar base. The photovoltaic technology issues to be addressed by the Surface Power program element of NASA's Project Pathfinder are described.

  4. Low-frequency switching voltage regulators for terrestrial photovoltaic systems

    NASA Technical Reports Server (NTRS)

    Delombard, R.

    1984-01-01

    The photovoltaic technology project and the stand alone applications project are discussed. Two types of low frequency switching type regulators were investigated. The design, operating characteristics and field application of these regulators is described. The regulators are small in size, low in cost, very low in power dissipation, reliable and allow considerable flexibility in system design.

  5. Design, construction and evaluation of two large photovoltaic power systems

    SciTech Connect

    Solman, F. J.; Nichols, B. E.

    1980-01-01

    A description and comparison of two large photovoltaic electric power systems is presented. The smaller system is designed for economic viability in the near future and provides 70 to 90 percent of the electric requirements for its prime load, a daytime AM radio station. The second system is a stand-alone power system suitable for a remote residential and light industrial community. No electric utility grid is present at this location so the management of a backup Diesel generator is also required.

  6. Federal policies to promote the widespread utilization of photovoltaic systems. Supplement: Review and critique

    NASA Technical Reports Server (NTRS)

    Smith, J. L.

    1980-01-01

    Review comments of the Congressional report entitled 'Federal Policies to Promote the Widespread Utilization of Photovoltaic Systems' are presented. Responses to the review comments by the Jet Propulsion Laboratory, preparer of the Congressional report, are also presented. The Congressional report discussed various issues related to promoting the deployment of photovoltaic systems through the Federal Photovoltaic Program. Various program strategies and funding levels were examined.

  7. Photovoltaic array mounting apparatus, systems, and methods

    DOEpatents

    West, John Raymond; Atchley, Brian; Hudson, Tyrus Hawkes; Johansen, Emil

    2014-12-02

    An apparatus for mounting a photovoltaic (PV) module on a surface, including a support with an upper surface, a lower surface, tabs, one or more openings, and a clip comprising an arm and a notch, where the apparatus resists wind forces and seismic forces and creates a grounding electrical bond between the PV module, support, and clip. The invention further includes a method for installing PV modules on a surface that includes arranging supports in rows along an X axis and in columns along a Y axis on a surface such that in each row the distance between two neighboring supports does not exceed the length of the longest side of a PV module and in each column the distance between two neighboring supports does not exceed the length of the shortest side of a PV module.

  8. Induction soldering of photovoltaic system components

    SciTech Connect

    Kumaria, Shashwat; de Leon, Briccio

    2015-11-17

    A method comprises positioning a pair of photovoltaic wafers in a side-by-side arrangement. An interconnect is placed on the pair of wafers such that the interconnect overlaps both wafers of the pair, solder material being provided between the interconnect and the respective wafers. A solder head is then located adjacent the interconnect, and the coil is energized to effect inductive heating of the solder material. The solder head comprises an induction coil shaped to define an eye, and a magnetic field concentrator located at least partially in the eye of the coil. The magnetic field concentrator defines a passage extending axially through the eye of the coil, and may be of a material with a high magnetic permeability.

  9. Sandia photovoltaic systems definition and application experiment projects

    SciTech Connect

    Jones, G.

    1983-04-01

    A compilation is given of the abstracts and visual material used in presentation at the Fourth Photovoltaic Systems Definition and Applications Projects Integration Meeting held at the Marriott Hotel, April 12-14, 1983, in Albuquerque, New Mexico. The meeting provided a forum for detailed analyses on recently completed and current activities. These activities include systems research, balance-of-system technology development, residential experimentation, and evaluation of intermediate-sized applications.

  10. A simulation approach to sizing hybrid photovoltaic and wind systems

    NASA Astrophysics Data System (ADS)

    Anderson, L. A.

    1983-12-01

    A simulation approach to sizing hybrid photovoltaic and wind systems provides a combination of components to realize zero downtime and minimum initial or life-cycle cost. Using Dayton, OH as a test site for weather data, cost advantages in the neighborhood of four are predicted for a hybrid system with battery storage when compared to a wind-energy-only system for the same electrical load.

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

    SciTech Connect

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

    1989-01-01

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

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

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

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

  13. Industrialization study, phase 2. [assessment of advanced photovoltaic technologies for commerical development

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The potentials and requirements of advanced photovoltaic technologies still in their early developmental stages were evaluated and compared to the present day single crystal silicon wafer technology and to each other. The major areas of consideration include polycrystalline and amorphous silicon, single crystal and polycrystalline gallium arsenide, and single crystal and polycrystalline cadmium sulfide. A rank ordering of the advanced technologies is provided. The various ranking schemes were based upon present-day efficiency levels, their stability and long-term reliability prospects, material availability, capital investments both at the laboratory and production level, and associated variable costs. An estimate of the timing of the possible readiness of these advanced technologies for technology development programs and industrialization is presented along with a set of recommended government actions concerning the various advanced technologies.

  14. Conceptual design and system analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 3: Appendices

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Hybrid photovoltaic/solar thermal electric conversion systems were analyzed. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems in terms of performance and cost were compared. The computer code used in the analyses and background information on heat engines, thermal efficiencies of photovoltaic thermal collectors, and optical considerations for central receiver plants is also described.

  15. Simulation of an active cooling system for photovoltaic modules

    NASA Astrophysics Data System (ADS)

    Abdelhakim, Lotfi

    2016-06-01

    Photovoltaic cells are devices that convert solar radiation directly into electricity. However, solar radiation increases the photovoltaic cells temperature [1] [2]. The temperature has an influence on the degradation of the cell efficiency and the lifetime of a PV cell. This work reports on a water cooling technique for photovoltaic panel, whereby the cooling system was placed at the front surface of the cells to dissipate excess heat away and to block unwanted radiation. By using water as a cooling medium for the photovoltaic solar cells, the overheating of closed panel is greatly reduced without prejudicing luminosity. The water also acts as a filter to remove a portion of solar spectrum in the infrared band but allows transmission of the visible spectrum most useful for the PV operation. To improve the cooling system efficiency and electrical efficiency, uniform flow rate among the cooling system is required to ensure uniform distribution of the operating temperature of the PV cells. The aims of this study are to develop a 3D thermal model to simulate the cooling and heat transfer in Photovoltaic panel and to recommend a cooling technique for the PV panel. The velocity, pressure and temperature distribution of the three-dimensional flow across the cooling block were determined using the commercial package, Fluent. The second objective of this work is to study the influence of the geometrical dimensions of the panel, water mass flow rate and water inlet temperature on the flow distribution and the solar panel temperature. The results obtained by the model are compared with experimental results from testing the prototype of the cooling device.

  16. DOE LeRC photovoltaic systems test facility

    NASA Technical Reports Server (NTRS)

    Cull, R. C.; Forestieri, A. F.

    1978-01-01

    The facility was designed and built and is being operated as a national facility to serve the needs of the entire DOE National Photovoltaic Program. The object of the facility is to provide a place where photovoltaic systems may be assembled and electrically configured, without specific physical configuration, for operation and testing to evaluate their performance and characteristics. The facility as a breadboard system allows investigation of operational characteristics and checkout of components, subsystems and systems before they are mounted in field experiments or demonstrations. The facility as currently configured consist of 10 kW of solar arrays built from modules, two inverter test stations, a battery storage system, interface with local load and the utility grid, and instrumentation and control necessary to make a flexible operating facility. Expansion to 30 kW is planned for 1978. Test results and operating experience are summaried to show the variety of work that can be done with this facility.

  17. Advanced Monitoring systems initiative

    SciTech Connect

    R.J. Venedam; E.O. Hohman; C.F. Lohrstorfer; S.J. Weeks; J.B. Jones; W.J. Haas

    2004-09-30

    The Advanced Monitoring Systems Initiative (AMSI) actively searches for promising technologies and aggressively moves them from the research bench into DOE/NNSA end-user applications. There is a large unfulfilled need for an active element that reaches out to identify and recruit emerging sensor technologies into the test and evaluation function. Sensor research is ubiquitous, with the seeds of many novel concepts originating in the university systems, but at present these novel concepts do not move quickly and efficiently into real test environments. AMSI is a widely recognized, self-sustaining ''business'' accelerating the selection, development, testing, evaluation, and deployment of advanced monitoring systems and components.

  18. Advanced, Cost-Based Indices for Forecasting the Generation of Photovoltaic Power

    NASA Astrophysics Data System (ADS)

    Bracale, Antonio; Carpinelli, Guido; Di Fazio, Annarita; Khormali, Shahab

    2014-01-01

    Distribution systems are undergoing significant changes as they evolve toward the grids of the future, which are known as smart grids (SGs). The perspective of SGs is to facilitate large-scale penetration of distributed generation using renewable energy sources (RESs), encourage the efficient use of energy, reduce systems' losses, and improve the quality of power. Photovoltaic (PV) systems have become one of the most promising RESs due to the expected cost reduction and the increased efficiency of PV panels and interfacing converters. The ability to forecast power-production information accurately and reliably is of primary importance for the appropriate management of an SG and for making decisions relative to the energy market. Several forecasting methods have been proposed, and many indices have been used to quantify the accuracy of the forecasts of PV power production. Unfortunately, the indices that have been used have deficiencies and usually do not directly account for the economic consequences of forecasting errors in the framework of liberalized electricity markets. In this paper, advanced, more accurate indices are proposed that account directly for the economic consequences of forecasting errors. The proposed indices also were compared to the most frequently used indices in order to demonstrate their different, improved capability. The comparisons were based on the results obtained using a forecasting method based on an artificial neural network. This method was chosen because it was deemed to be one of the most promising methods available due to its capability for forecasting PV power. Numerical applications also are presented that considered an actual PV plant to provide evidence of the forecasting performances of all of the indices that were considered.

  19. Power conditioning subsystems for photovoltaic central-station power plants - State-of-the-art and advanced technology

    NASA Technical Reports Server (NTRS)

    Bulawka, A.; Krauthamer, S.; Das, R.

    1986-01-01

    An overview is given of the technical and near-term cost requirements that must be met to develop economically viable power conditioning subsystems (PCS) for large-scale, central photovoltaic power stations. Various commercially available PCS hardware suitable for use in today's central photovoltaic power stations are also surveyed. Federal and industrial activities in the research and development of advanced PCSs that will contribute to the attainment of fully competitive, large-scale photovoltaic power stations are reviewed. The status of the DOE central station PCS program is discussed.

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  1. Design, analysis and test verification of advanced encapsulation systems

    NASA Technical Reports Server (NTRS)

    Garcia, A., III

    1982-01-01

    An analytical methodology for advanced encapsulation designs was developed. From these methods design sensitivities are established for the development of photovoltaic module criteria and the definition of needed research tasks. Analytical models were developed to perform optical, thermal, electrical and analyses on candidate encapsulation systems. From these analyses several candidate systems were selected for qualification testing. Additionally, test specimens of various types are constructed and tested to determine the validity of the analysis methodology developed. Identified deficiencies and/or discrepancies between analytical models and relevant test data are corrected. Prediction capability of analytical models is improved. Encapsulation engineering generalities, principles, and design aids for photovoltaic module designers is generated.

  2. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-12-31

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  3. Advanced turbine systems program

    SciTech Connect

    Wilkes, C.; Mukavetz, D.W.; Knickerbocker, T.K.; Ali, S.A.

    1992-01-01

    In accordance with the goals of the DOE program, improvements in the gas turbine are the primary focus of Allison activity during Phase I. To this end Allison conducted a survey of potentially applicable gas turbine cycles and selected the advanced combined cycle as reference system. Extensive analysis of two versions of the advanced combined cycle was performed against the requirement for a 60% thermal efficiency (LHV) utility-sized, natural gas fired system. This analysis resulted in technology requirements for this system. Additional analysis determined emissions potential for the system, established a coal-fueled derivative system and a commercialization plan. This report deals with the technical requirements for a system that meets the thermal efficiency goal. Allison initially investigated four basic thermodynamic cycles: Humid air turbine, intercalate-recuperated systems, advanced combined cycle, chemically recuperated cycle. Our survey and cycle analysis indicated that au had the potential of reaching 60% thermal efficiency. We also concluded that engine hot section technology would be a critical technology regardless of which cycle was chosen. Based on this result Allison chose to concentrate on the advanced combined cycle. This cycle is well known and understood by the utility turbine user community and is therefore likely to be acceptable to users.

  4. Photovoltaic power system operation in the Mars environment

    NASA Technical Reports Server (NTRS)

    Appelbaum, Joseph; Flood, Dennis J.

    1989-01-01

    Detailed information on the environmental conditions on Mars are very desirable for the design of photovoltaic systems for establishing outposts on the Martian surface. The variation of solar insolation (global, direct, and diffuse) at the Viking lander's locations is addressed. It can be used, to a first approximation, for other latitudes. The radiation data is based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation. The data are used to make estimates of photovoltaic system power, area and mass for a surface power system using regenerative fuel cells for storage and nighttime operation.

  5. Advanced Solar Power Systems

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

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

  6. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2005-02-08

    An advanced containment system for containing buried waste and associated leachate. The advanced containment system comprises a plurality of casing sections with each casing section interlocked to an adjacent casing section. Each casing section includes a complementary interlocking structure that interlocks with the complementary interlocking structure on an adjacent casing section. A barrier filler substantially fills the casing sections and may substantially fill the spaces of the complementary interlocking structure to form a substantially impermeable barrier. Some of the casing sections may include sensors so that the casing sections and the zone of interest may be remotely monitored after the casing sections are emplaced in the ground.

  7. Residential photovoltaic flywheel storage system performance and cost

    SciTech Connect

    Hay, R.D.; Millner, A.R.; Jarvinen, P.O.

    1980-01-01

    A subscale prototype of a flywheel energy storage and conversion system for use with photovoltaic power systems of residential and intermediate load-center size has been designed, built and tested by MIT Lincoln Laboratory. System design, including details of such key components as magnetic bearings, motor generator, and power-conditioning electronics, are described. Performance results of prototype testing are given and indicate that this system is the equal of or superior to battery and inverter systems for the same application. Results of cost and user-worth analysis show that residential systems are economically feasible in stand-alone and in utility-interactive applications.

  8. Evaluation of critical materials in five additional advance design photovoltaic cells

    SciTech Connect

    Smith, S.A.; Watts, R.L.; Martin, P.; Gurwell, W.E.

    1981-02-01

    The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. The Critical Materials Assessment Program (CMAP) screens the designs and their supply chains and identifies potential shortages which might preclude large-scale use of the technologies. The results of the screening of five advanced PV cell designs are presented: (1) indium phosphide/cadmium sulfide, (2) zinc phosphide, (3) cadmium telluride/cadmium sulfide, (4) copper indium selenium, and (5) cadmium selenide photoelectrochemical. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 Gwe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has a 5 GWe of peak capacity by the year 2000, so that the total online capacity for the five cells is 25 GWe. Based on a review of the preliminary baseline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. The CMAP methodology used to identify critical materials is described; and detailed characterizations of the advanced photovoltaic cell designs under investigation, descriptions of additional cell production processes, and the results are presented. (WHK)

  9. Manufacturing technology development of the Powergrid{trademark} linear focus photovoltaic concentrator system

    SciTech Connect

    Kaminar, N.; Alexander, T.; Amaya, J.; Bottenberg, W.; Carrie, P.; Chen, K.; Gilbert, D.; Guzman, P.; Hobden, P.; Ross, J.; Sahagian, J.; Rodrigues, D.; Zimmermann, J.

    1999-03-01

    This article reports manufacturing technology improvements developed for the production of the PVI Powergrid{trademark} linear focus photovoltaic concentrator as part of a PVMaT project. The improvements include the development of an advanced, acrylic plastic extrusion system for Fresnel lenses, an automated receiver station, an EVA encapsulation process, an improved collector fabrication method and a lower cost panel frame. These project improvements have prepared PVI for entrance into large-scale production of PV power generation systems. {copyright} {ital 1999 American Institute of Physics.}

  10. Photovoltaic stand-alone modular systems, phase 2

    NASA Technical Reports Server (NTRS)

    Naff, G. J.; Marshall, N. A.

    1983-01-01

    The final hardware and system qualification phase of a two part stand-alone photovoltaic (PV) system development is covered. The final design incorporated modular, power blocks capable of expanding incrementally from 320 watts to twenty kilowatts (PK). The basic power unit (PU) was nominally rated 1.28 kWp. The controls units, power collection buses and main lugs, electrical protection subsystems, power switching, and load management circuits are housed in a common control enclosure. Photo-voltaic modules are electrically connected in a horizontal daisy-chain method via Amp Solarlok plugs mating with compatible connectors installed on the back side of each photovoltaic module. A pair of channel rails accommodate the mounting of the modules into a frameless panel support structure. Foundations are of a unique planter (tub-like) configuration to allow for world-wide deployment without restriction as to types of soil. One battery string capable of supplying approximately 240 ampere hours nominal of carryover power is specified for each basic power unit. Load prioritization and shedding circuits are included to protect critical loads and selectively shed and defer lower priority or noncritical power demands. The baseline system, operating at approximately 2 1/2 PUs (3.2 kW pk.) was installed and deployed. Qualification was successfully complete in March 1983; since that time, the demonstration system has logged approximately 3000 hours of continuous operation under load without major incident.

  11. Distributed photovoltaic systems - Addressing the utility interface issues

    NASA Astrophysics Data System (ADS)

    Firstman, S. I.; Vachtsevanos, G. J.

    This paper reviews work conducted in the United States on the impact of dispersed photovoltaic sources upon utility operations. The photovoltaic (PV) arrays are roof-mounted on residential houses and connected, via appropriate power conditioning equipment, to the utility grid. The presence of such small (4-6 Kw) dispersed generators on the distribution network raises questions of a technical, economic and institutional nature. After a brief identification of utility interface issues, the paper addresses such technical concerns as protection of equipment and personnel safety, power quality and utility operational stability. A combination of experimental and analytical approaches has been adopted to arrive at solutions to these problems. Problem areas, under various PV system penetration scenarios, are identified and conceptual designs of protection and control equipment and operating policies are developed so that system reliability is maintained while minimizing capital costs. It is hoped that the resolution of balance-of-system and grid interface questions will ascertain the economic viability of photovoltaic systems and assist in their widespread utilization in the future.

  12. Interconnection of a photovoltaic power generation system with the grid

    NASA Astrophysics Data System (ADS)

    Corbefin, R.; Vacelet, G.

    Converting photovoltaic system-generated power into a form compatible with grid-furnished power and simultaneously ensuring that maximal power is drawn from the solar system is discussed. A converter is interposed between the solar-derived electricity and the grid lines, allowing the user to apply the power to a load, feed excess power to the grid, and receive power from the grid when the photovoltaic output is too low to fill demand. A dc-ac converter is described, with microprocessor controlled transistorized switching to adapt the solar output to the load amplitude on demand, while maintaining constant voltage. An adaptor allows the converter to take its amplitude, phase, and frequency regulation from the grid, and also assures that power will flow only toward the grid.

  13. A quantitative method for photovoltaic encapsulation system optimization

    NASA Technical Reports Server (NTRS)

    Garcia, A., III; Minning, C. P.; Cuddihy, E. F.

    1981-01-01

    It is pointed out that the design of encapsulation systems for flat plate photovoltaic modules requires the fulfillment of conflicting design requirements. An investigation was conducted with the objective to find an approach which will make it possible to determine a system with optimum characteristics. The results of the thermal, optical, structural, and electrical isolation analyses performed in the investigation indicate the major factors in the design of terrestrial photovoltaic modules. For defect-free materials, minimum encapsulation thicknesses are determined primarily by structural considerations. Cell temperature is not strongly affected by encapsulant thickness or thermal conductivity. The emissivity of module surfaces exerts a significant influence on cell temperature. Encapsulants should be elastomeric, and ribs are required on substrate modules. Aluminum is unsuitable as a substrate material. Antireflection coating is required on cell surfaces.

  14. Photovoltaic system criteria documents. Volume 1: Guidelines for evaluating the management and operations planning of photovoltaic applications

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    Guidelines are provided to the Field Centers for organization, scheduling, project and cost control, and performance in the areas of project management and operations planning for Photovoltaics Test and Applications. These guidelines may be used in organizing a T and A Project Team for system design/test, site construction and operation, and as the basis for evaluating T and A proposals. The attributes are described for project management and operations planning to be used by the Field Centers. Specifically, all project management and operational issues affecting costs, schedules and performance of photovoltaic systems are addressed. Photovoltaic tests and applications include residential, intermediate load center, central station, and stand-alone systems. The sub-categories of system maturity considered are: Initial System Evaluation Experiments (ISEE); System Readiness Experiments (SRE); and Commercial Readiness Demonstration Projects (CRDP).

  15. Cost Analysis of a Concentrator Photovoltaic Hydrogen Production System

    SciTech Connect

    Thompson, J. R.; McConnell, R. D.; Mosleh, M.

    2005-08-01

    The development of efficient, renewable methods of producing hydrogen are essential for the success of the hydrogen economy. Since the feedstock for electrolysis is water, there are no harmful pollutants emitted during the use of the fuel. Furthermore, it has become evident that concentrator photovoltaic (CPV) systems have a number of unique attributes that could shortcut the development process, and increase the efficiency of hydrogen production to a point where economics will then drive the commercial development to mass scale.

  16. Advanced Distribution Management System

    NASA Astrophysics Data System (ADS)

    Avazov, Artur R.; Sobinova, Liubov A.

    2016-02-01

    This article describes the advisability of using advanced distribution management systems in the electricity distribution networks area and considers premises of implementing ADMS within the Smart Grid era. Also, it gives the big picture of ADMS and discusses the ADMS advantages and functionalities.

  17. Thermal control system for Space Station Freedom photovoltaic power module

    NASA Technical Reports Server (NTRS)

    Hacha, Thomas H.; Howard, Laura

    1994-01-01

    The electric power for Space Station Freedom (SSF) is generated by the solar arrays of the photovoltaic power modules (PVM's) and conditioned, controlled, and distributed by a power management and distribution system. The PVM's are located outboard of the alpha gimbals of SSF. A single-phase thermal control system is being developed to provide thermal control of PVM electrical equipment and energy storage batteries. This system uses ammonia as the coolant and a direct-flow deployable radiator. The description and development status of the PVM thermal control system is presented.

  18. Thermal control system for Space Station Freedom photovoltaic power module

    NASA Technical Reports Server (NTRS)

    Hacha, Thomas H.; Howard, Laura S.

    1992-01-01

    The electric power for Space Station Freedom (SSF) is generated by the solar arrays of the photovoltaic power modules (PVM's) and conditioned, controlled, and distributed by a power management and distribution system. The PVM's are located outboard of the alpha gimbals of SSF. A single-phase thermal control system is being developed to provide thermal control of PVM electrical equipment and energy storage batteries. This system uses ammonia as the coolant and a direct-flow deployable radiator. This paper presents the description and development status of the PVM thermal control system.

  19. A novel hybrid (wind-photovoltaic) system sizing procedure

    SciTech Connect

    Hocaoglu, Fatih O.; Gerek, Oemer N.; Kurban, Mehmet

    2009-11-15

    Wind-photovoltaic hybrid system (WPHS) utilization is becoming popular due to increasing energy costs and decreasing prices of turbines and photovoltaic (PV) panels. However, prior to construction of a renewable generation station, it is necessary to determine the optimum number of PV panels and wind turbines for minimal cost during continuity of generated energy to meet the desired consumption. In fact, the traditional sizing procedures find optimum number of the PV modules and wind turbines subject to minimum cost. However, the optimum battery capacity is either not taken into account, or it is found by a full search between all probable solution spaces which requires extensive computation. In this study, a novel description of the production/consumption phenomenon is proposed, and a new sizing procedure is developed. Using this procedure, optimum battery capacity, together with optimum number of PV modules and wind turbines subject to minimum cost can be obtained with good accuracy. (author)

  20. Advanced dive monitoring system.

    PubMed

    Sternberger, W I; Goemmer, S A

    1999-01-01

    The US Navy supports deep diving operations with a variety of mixed-gas life support systems. A systems engineering study was conducted for the Naval Experimental Dive Unit (Panama City, FL) to develop a concept design for an advanced dive monitoring system. The monitoring system is intended primarily to enhance diver safety and secondarily to support diving medicine research. Distinct monitoring categories of diver physiology, life support system, and environment are integrated in the monitoring system. A system concept is proposed that accommodates real-time and quantitative measurements, noninvasive physiological monitoring, and a flexible and expandable implementation architecture. Human factors and ergonomic design considerations have been emphasized to assure that there is no impact on the diver's primary mission. The Navy has accepted the resultant system requirements and the basic design concept. A number of monitoring components have been implemented and successfully support deep diving operations.

  1. Space Station Power System Advanced Development

    NASA Technical Reports Server (NTRS)

    Forestieri, A. F.; Baraona, C. R.; Valgora, M. E.

    1985-01-01

    The objectives of the Space Station Advanced Development Program are related to the development of a set of design options and/or new capabilities to support Space Station development and operation, taking into account also a quantification of the performance and risk of key state-of-the-art technologies, and a reduction of the cost and schedule risk in Space Station development. Attention is given to the photovoltaic power system, a solar dynamic system, and aspects of power management and distribution. A major issue will be the selection of the power generation system. In view of the advantages of the solar dynamic system, it is attempted to resolve issues associated with this system.

  2. Models used to assess the performance of photovoltaic systems.

    SciTech Connect

    Stein, Joshua S.; Klise, Geoffrey T.

    2009-12-01

    This report documents the various photovoltaic (PV) performance models and software developed and utilized by researchers at Sandia National Laboratories (SNL) in support of the Photovoltaics and Grid Integration Department. In addition to PV performance models, hybrid system and battery storage models are discussed. A hybrid system using other distributed sources and energy storage can help reduce the variability inherent in PV generation, and due to the complexity of combining multiple generation sources and system loads, these models are invaluable for system design and optimization. Energy storage plays an important role in reducing PV intermittency and battery storage models are used to understand the best configurations and technologies to store PV generated electricity. Other researcher's models used by SNL are discussed including some widely known models that incorporate algorithms developed at SNL. There are other models included in the discussion that are not used by or were not adopted from SNL research but may provide some benefit to researchers working on PV array performance, hybrid system models and energy storage. The paper is organized into three sections to describe the different software models as applied to photovoltaic performance, hybrid systems, and battery storage. For each model, there is a description which includes where to find the model, whether it is currently maintained and any references that may be available. Modeling improvements underway at SNL include quantifying the uncertainty of individual system components, the overall uncertainty in modeled vs. measured results and modeling large PV systems. SNL is also conducting research into the overall reliability of PV systems.

  3. Enhanced EOS photovoltaic power system capability with InP solar cells

    NASA Technical Reports Server (NTRS)

    Bailey, Sheila G.; Weinberg, Irving; Flood, Dennis J.

    1991-01-01

    The Earth Observing System (EOS), which is part of the International Mission to Planet Earth, is NASA's main contribution to the Global Change Research Program which opens a new era in international cooperation to study the Earth's environment. Five large platforms are to be launched into polar orbit, two by NASA, two by ESA, and one by the Japanese. In such an orbit the radiation resistance of indium phosphide solar cells combined with the potential of utilizing five micron cell structures yields an increase of 10 percent in the payload capability. If further combined with the advanced photovoltaic solar array the payload savings approaches 12 percent.

  4. Advanced imaging system

    NASA Technical Reports Server (NTRS)

    1992-01-01

    This document describes the Advanced Imaging System CCD based camera. The AIS1 camera system was developed at Photometric Ltd. in Tucson, Arizona as part of a Phase 2 SBIR contract No. NAS5-30171 from the NASA/Goddard Space Flight Center in Greenbelt, Maryland. The camera project was undertaken as a part of the Space Telescope Imaging Spectrograph (STIS) project. This document is intended to serve as a complete manual for the use and maintenance of the camera system. All the different parts of the camera hardware and software are discussed and complete schematics and source code listings are provided.

  5. Advanced Life Support Systems

    NASA Technical Reports Server (NTRS)

    Barta, Daniel J.

    2004-01-01

    This presentation is planned to be a 10-15 minute "catalytic" focused presentation to be scheduled during one of the working sessions at the TIM. This presentation will focus on Advanced Life Support technologies key to future human Space Exploration as outlined in the Vision, and will include basic requirements, assessment of the state-of-the-art and gaps, and include specific technology metrics. The presentation will be technical in character, lean heavily on data in published ALS documents (such as the Baseline Values and Assumptions Document) but not provide specific technical details or build to information on any technology mentioned (thus the presentation will be benign from an export control and a new technology perspective). The topics presented will be focused on the following elements of Advanced Life Support: air revitalization, water recovery, waste management, thermal control, habitation systems, food systems and bioregenerative life support.

  6. Photovoltaic Energy Program Overview Fiscal Year 1996

    SciTech Connect

    1997-05-01

    Significant activities in the National Photovoltaic Program are reported for each of the three main program elements. In Research and Development, advances in thin-film materials and crystalline silicon materials are described. The Technology Development report describes activities in photovoltaic manufacturing technology, industrial expansion, module and array development, and testing photovoltaic system components. Systems Engineering and Applications projects described include projects with government agencies, projects with utilities, documentation of performance for international applications, and product certification.

  7. Photovoltaics: Program overview, fiscal year 1992

    SciTech Connect

    Not Available

    1993-03-01

    The US DOE`s Photovoltaics program has helped photovoltaic technologies evolve from materials and concepts in the laboratories to competitive products rolling off automated assembly lines. This document is divided into the following sections: 1992 PV program accomplishments, expanding markets for photovoltaic systems, developing today`s systems with utilities and industry, working with industry to advance the technology, cooperative research to improve materials and devices, selected achievements in cooperative R and D, and PV program services. Figs, tabs.

  8. Design description of the Tangaye Village photovoltaic power system

    NASA Technical Reports Server (NTRS)

    Martz, J. E.; Ratajczak, A. F.

    1982-01-01

    The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

  9. Design description of the Tangaye Village photovoltaic power system

    NASA Astrophysics Data System (ADS)

    Martz, J. E.; Ratajczak, A. F.

    1982-06-01

    The engineering design of a stand alone photovoltaic (PV) powered grain mill and water pump for the village of Tangaye, Upper Volta is described. The socioeconomic effects of reducing the time required by women in rural areas for drawing water and grinding grain were studied. The suitability of photovoltaic technology for use in rural areas by people of limited technical training was demonstrated. The PV system consists of a 1.8-kW (peak) solar cell array, 540 ampere hours of battery storage, instrumentation, automatic controls, and a data collection and storage system. The PV system is situated near an improved village well and supplies d.c. power to a grain mill and a water pump. The array is located in a fenced area and the mill, battery, instruments, controls, and data system are in a mill building. A water storage tank is located near the well. The system employs automatic controls which provide battery charge regulation and system over and under voltage protection. This report includes descriptions of the engineering design of the system and of the load that it serves; a discussion of PV array and battery sizing methodology; descriptions of the mechanical and electrical designs including the array, battery, controls, and instrumentation; and a discussion of the safety features. The system became operational on March 1, 1979.

  10. A photovoltaic power system and a low-power satellite earth station for Indonesia

    NASA Technical Reports Server (NTRS)

    Delombard, Richard; Everson, Kent

    1985-01-01

    A photovoltaic power system and a low-power, two-way satellite earth station have been installed at Wawotobi, Sulawesi, Indonesia to provide university classroom communications for audio teleconferencing and video graphics. This project is a part of the Agency for International Development's Rural Satellite Program. The purpose of this program is to demonstrate the use of satellite communications for development assistance applications. The purpose of the photovoltaic power system is to demonstrate the suitability of a hybrid photovoltaic/engine-generator power system for a remote satellite earth station. This paper describes the design, installation and initial operation of the photovoltaic power system and the earth station.

  11. A photovoltaic power system and a low-power satellite earth station for Indonesia

    NASA Astrophysics Data System (ADS)

    Delombard, Richard; Everson, Kent

    A photovoltaic power system and a low-power, two-way satellite earth station have been installed at Wawotobi, Sulawesi, Indonesia to provide university classroom communications for audio teleconferencing and video graphics. This project is a part of the Agency for International Development's Rural Satellite Program. The purpose of this program is to demonstrate the use of satellite communications for development assistance applications. The purpose of the photovoltaic power system is to demonstrate the suitability of a hybrid photovoltaic/engine-generator power system for a remote satellite earth station. This paper describes the design, installation and initial operation of the photovoltaic power system and the earth station.

  12. Photovoltaic battery & charge controller market & applications survey. An evaluation of the photovoltaic system market for 1995

    SciTech Connect

    Hammond, R.L.; Turpin, J.F.; Corey, G.P.

    1996-12-01

    Under the sponsorship of the Department of Energy, Office of Utility Technologies, the Battery Analysis and Evaluation Department and the Photovoltaic System Assistance Center of Sandia National Laboratories (SNL) initiated a U.S. industry-wide PV Energy Storage System Survey. Arizona State University (ASU) was contracted by SNL in June 1995 to conduct the survey. The survey included three separate segments tailored to: (a) PV system integrators, (b) battery manufacturers, and (c) PV charge controller manufacturers. The overall purpose of the survey was to: (a) quantify the market for batteries shipped with (or for) PV systems in 1995, (b) quantify the PV market segments by battery type and application for PV batteries, (c) characterize and quantify the charge controllers used in PV systems, (d) characterize the operating environment for energy storage components in PV systems, and (e) estimate the PV battery market for the year 2000. All three segments of the survey were mailed in January 1996. This report discusses the purpose, methodology, results, and conclusions of the survey.

  13. 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.

  14. A solar photovoltaic power system for use in Antarctica

    NASA Astrophysics Data System (ADS)

    Kohout, Lisa L.; Merolla, Anthony; Colozza, Anthony

    1993-12-01

    A solar photovoltaic power system was designed and built at the NASA Lewis Research Center as part of the NASA/NSF Antarctic Space Analog Program. The system was installed at a remote field camp at Lake Hoare in the Dry Valleys, and provided a six-person field team with electrical power for personal computers and printers, lab equipment, lighting, and a small microwave oven. The system consists of three silicon photovoltaic sub-arrays delivering a total of 1.5 kWe peak power, three lead-acid gel battery modules supplying 2.4 kWh, and an electrical distribution system which delivers 120 Vac and 12 Vdc to the user. The system was modularized for ease of deployment and operation. Previously the camp has been powered by diesel generators, which have proven to be both noisy and polluting. The NSF, in an effort to reduce their dependence on diesel fuel from both an environmental and cost standpoint, is interested in the use of alternate forms of energy, such as solar power. Such a power system also will provide NASA with important data on system level deployment and operation in a remote location by a minimally trained crew, as well as validate initial integration concepts.

  15. A solar photovoltaic power system for use in Antarctica

    NASA Astrophysics Data System (ADS)

    Kohout, Lisa L.; Colozza, A. J.; Merolla, A.

    A solar photovoltaic power system was designed and built at the NASA Lewis Research Center as part of the NASA/NSF Antarctic Space Analog Program. The system was installed at a remote field camp at Lake Hoare in the Dry Valleys and provided a six-person field team with the power to run personal computers and printers, lab equipment, lightning, and a small microwave oven. The system consists of three silicon photovoltaic sub-arrays delivering 1.5 kW peak power, three lead-acid gel battery modules supplying 2.4 kWh, and electrical distribution system which delivers 120 Vac and 12 Vdc to the user. The system was modularized for each of deployment and operation. Previously the camp has been powered by diesel generators, which have proven to be both noisy and polluting. The NSF, in an effort to reduce their dependence on diesel fuel from both and environmental and cost standpoint is interested in the use of alternate forms of energy, such as solar power. Such a power system will also provide NASA with important data on system level deployment and operation in a remote location by a minimally trained crew, as well as validate initial integration concepts.

  16. A solar photovoltaic power system for use in Antarctica

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.; Merolla, Anthony; Colozza, Anthony

    1993-01-01

    A solar photovoltaic power system was designed and built at the NASA Lewis Research Center as part of the NASA/NSF Antarctic Space Analog Program. The system was installed at a remote field camp at Lake Hoare in the Dry Valleys, and provided a six-person field team with electrical power for personal computers and printers, lab equipment, lighting, and a small microwave oven. The system consists of three silicon photovoltaic sub-arrays delivering a total of 1.5 kWe peak power, three lead-acid gel battery modules supplying 2.4 kWh, and an electrical distribution system which delivers 120 Vac and 12 Vdc to the user. The system was modularized for ease of deployment and operation. Previously the camp has been powered by diesel generators, which have proven to be both noisy and polluting. The NSF, in an effort to reduce their dependence on diesel fuel from both an environmental and cost standpoint, is interested in the use of alternate forms of energy, such as solar power. Such a power system also will provide NASA with important data on system level deployment and operation in a remote location by a minimally trained crew, as well as validate initial integration concepts.

  17. A solar photovoltaic power system for use in Antarctica

    NASA Technical Reports Server (NTRS)

    Kohout, Lisa L.; Colozza, A. J.; Merolla, A.

    1994-01-01

    A solar photovoltaic power system was designed and built at the NASA Lewis Research Center as part of the NASA/NSF Antarctic Space Analog Program. The system was installed at a remote field camp at Lake Hoare in the Dry Valleys and provided a six-person field team with the power to run personal computers and printers, lab equipment, lightning, and a small microwave oven. The system consists of three silicon photovoltaic sub-arrays delivering 1.5 kW peak power, three lead-acid gel battery modules supplying 2.4 kWh, and electrical distribution system which delivers 120 Vac and 12 Vdc to the user. The system was modularized for each of deployment and operation. Previously the camp has been powered by diesel generators, which have proven to be both noisy and polluting. The NSF, in an effort to reduce their dependence on diesel fuel from both and environmental and cost standpoint is interested in the use of alternate forms of energy, such as solar power. Such a power system will also provide NASA with important data on system level deployment and operation in a remote location by a minimally trained crew, as well as validate initial integration concepts.

  18. Residential Photovoltaic/Thermal Energy System

    NASA Technical Reports Server (NTRS)

    Selcuk, M. K.

    1987-01-01

    Proposed system supplies house with both heat and electricity. Pair of reports describes concept for self-sufficient heating, cooling, and power-generating system for house. Panels on walls of house provide hot water, space heating, and heat to charge heat-storage system, and generate electricity for circulation pumps and fans. Roof panels generate electricity for household, operate heat pump for summer cooling, and provide supplementary winter heating via heat pump, using solar-cell cooling-fluid loop. Wall and roof panels used independently.

  19. 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.

  20. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-the-shelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  1. Advanced Clothing System

    NASA Technical Reports Server (NTRS)

    Schlesinger, Thilini; Broyan, James; Orndoff, Evelyne

    2014-01-01

    The goal of the Advanced Clothing System (ACS) is to use advanced commercial off-theshelf fibers and antimicrobial treatments with the goal of directly reducing the mass and volume of a logistics item. The current clothing state-of-the-art on the International Space Station (ISS) is disposable, mostly cotton-based, clothing with no laundry provisions. Each clothing article has varying use periods and will become trash. The goal is to increase the length of wear of the clothing to reduce the logistical mass and volume. The initial focus has been exercise clothing since the use period is lower. Various ground studies and an ISS technology demonstration have been conducted to evaluate clothing preference and length of wear. The analysis indicates that use of ACS selected garments (e.g. wool, modacrylic, polyester) can increase the breakeven point for laundry to 300 days.

  2. Photovoltaic System Modeling. Uncertainty and Sensitivity Analyses

    SciTech Connect

    Hansen, Clifford W.; Martin, Curtis E.

    2015-08-01

    We report an uncertainty and sensitivity analysis for modeling AC energy from ph otovoltaic systems . Output from a PV system is predicted by a sequence of models. We quantify u ncertainty i n the output of each model using empirical distribution s of each model's residuals. We propagate uncertainty through the sequence of models by sampli ng these distributions to obtain a n empirical distribution of a PV system's output. We consider models that: (1) translate measured global horizontal, direct and global diffuse irradiance to plane - of - array irradiance; (2) estimate effective irradiance; (3) predict cell temperature; (4) estimate DC voltage, current and power ; (5) reduce DC power for losses due to inefficient maximum power point tracking or mismatch among modules; and (6) convert DC to AC power . O ur analysis consider s a notional PV system com prising an array of FirstSolar FS - 387 modules and a 250 kW AC inverter ; we use measured irradiance and weather at Albuquerque, NM. We found the uncertainty in PV syste m output to be relatively small, on the order of 1% for daily energy. We found that unce rtainty in the models for POA irradiance and effective irradiance to be the dominant contributors to uncertainty in predicted daily energy. Our analysis indicates that efforts to reduce the uncertainty in PV system output predictions may yield the greatest improvements by focusing on the POA and effective irradiance models.

  3. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-12-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project will result in the development of an Advanced Worker Protection System (AWPS). The AWPS will be built around a life support backpack that uses liquid air to provide cooling as well as breathing gas to the worker. The backpack will be combined with advanced protective garments, advanced liquid cooling garment, respirator, communications, and support equipment to provide improved worker protection, simplified system maintenance, and dramatically improve worker productivity through longer duration work cycles. Phase I of the project has resulted in a full scale prototype Advanced Worker Protection Ensemble (AWPE, everything the worker will wear), with sub-scale support equipment, suitable for integrated testing and preliminary evaluation. Phase II will culminate in a full scale, certified, pre-production AWPS and a site demonstration.

  4. Photovoltaics and Wind Power Systems. Course Syllabus.

    ERIC Educational Resources Information Center

    Bergen County Vocational-Technical High School, Hackensack, NJ.

    This course is one of four in a solar systems and energy management program developed by the Bergen County Vocational-Technical Schools to help tradespeople (heating, ventilation, and air conditioning mechanics; plumbers; and electricians) to develop an awareness of alternate energy sources and to gain skills in the areas of solar installations…

  5. Photovoltaic generating systems in rural schools in Neuquen Province, Argentina

    SciTech Connect

    Lawand, T.A.; Campbell, J.

    1997-12-01

    During the period 1994-95, solar photovoltaic systems were installed at a number of schools in Neuquen Province, Argentina, by the Provincial electric utility, Ente Provincial de Energia del Neuquen. This was undertaken with funds provided by the Inter-American Development Bank. In all, there are 12 schools that have had photovoltaic generating systems installed. These generating systems are designed to provide electricity for the basic needs at the schools: primarily for lighting, and to operate small electrical appliances such as communication radios, televisions, VCR`s, AM/FM and short-wave radios. They do not provide enough energy to operate large consumption appliances such as washing machines, microwaves, refrigerators, power tools, etc. The program of provision of PV systems was supplemented with training on simple systems for cooking food or drying fruit, etc. These techniques are primarily intended for demonstration at the schools thus serving an educational role with the hope that they will be transmitted in time to the families of the students where the need is manifested the most.

  6. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Gregory Gaul

    2004-04-21

    Natural gas combustion turbines are rapidly becoming the primary technology of choice for generating electricity. At least half of the new generating capacity added in the US over the next twenty years will be combustion turbine systems. The Department of Energy has cosponsored with Siemens Westinghouse, a program to maintain the technology lead in gas turbine systems. The very ambitious eight year program was designed to demonstrate a highly efficient and commercially acceptable power plant, with the ability to fire a wide range of fuels. The main goal of the Advanced Turbine Systems (ATS) Program was to develop ultra-high efficiency, environmentally superior and cost effective competitive gas turbine systems for base load application in utility, independent power producer and industrial markets. Performance targets were focused on natural gas as a fuel and included: System efficiency that exceeds 60% (lower heating value basis); Less than 10 ppmv NO{sub x} emissions without the use of post combustion controls; Busbar electricity that are less than 10% of state of the art systems; Reliability-Availability-Maintainability (RAM) equivalent to current systems; Water consumption minimized to levels consistent with cost and efficiency goals; and Commercial systems by the year 2000. In a parallel effort, the program was to focus on adapting the ATS engine to coal-derived or biomass fuels. In Phase 1 of the ATS Program, preliminary investigators on different gas turbine cycles demonstrated that net plant LHV based efficiency greater than 60% was achievable. In Phase 2 the more promising cycles were evaluated in greater detail and the closed-loop steam-cooled combined cycle was selected for development because it offered the best solution with least risk for achieving the ATS Program goals for plant efficiency, emissions, cost of electricity and RAM. Phase 2 also involved conceptual ATS engine and plant design and technology developments in aerodynamics, sealing

  7. Dye Sensitized Solar Cells for Economically Viable Photovoltaic Systems.

    PubMed

    Jung, Hyun Suk; Lee, Jung-Kun

    2013-05-16

    TiO2 nanoparticle-based dye sensitized solar cells (DSSCs) have attracted a significant level of scientific and technological interest for their potential as economically viable photovoltaic devices. While DSSCs have multiple benefits such as material abundance, a short energy payback period, constant power output, and compatibility with flexible applications, there are still several challenges that hold back large scale commercialization. Critical factors determining the future of DSSCs involve energy conversion efficiency, long-term stability, and production cost. Continuous advancement of their long-term stability suggests that state-of-the-art DSSCs will operate for over 20 years without a significant decrease in performance. Nevertheless, key questions remain in regards to energy conversion efficiency improvements and material cost reduction. In this Perspective, the present state of the field and the ongoing efforts to address the requirements of DSSCs are summarized with views on the future of DSSCs.

  8. Power conditioning unit for photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Beghin, G.; Nguyen Phuoc, V. T.

    Operational features and components of a power conditioning unit for interconnecting solar cell module powers with a utility grid are outlined. The two-stage unit first modifies the voltage to desired levels on an internal dc link, then inverts the current in 2 power transformers connected to a vector summation control to neutralize harmonic distortion up to the 11th harmonic. The system operates in parallel with the grid with extra inductors to absorb line-to-line voltage and phase differences, and permits peak power use from the PV array. Reactive power is gained internally, and a power system controller monitors voltages, frequencies, and currents. A booster preregulator adjusts the input voltage from the array to provide voltage regulation for the inverter, and can commutate 450 amps. A total harmonic distortion of less than 5 percent is claimed, with a rating of 5 kVA, 50/60 Hz, 3-phase, and 4-wire.

  9. Advanced Thermal Conversion Systems

    DTIC Science & Technology

    2015-03-18

    BAA09-31 3  Figure 1. (a) Energy diagram of the PETE process. Photo -excitation leads to enhanced...photovoltaic cells at 3000x concentration (~38%). As shown in Fig. 2(b), the highest conversion efficiencies are obtained by using photo -cathodes...p-type 4H-SiC (left) and polycrystalline n-type 3C-SiC (right). The fabrication process for p-type devices used bulk p- doped 4H-SiC wafers from

  10. Temperature dependence of photovoltaic cells, modules, and systems

    SciTech Connect

    Emery, K.; Burdick, J.; Caiyem, Y.

    1996-05-01

    Photovoltaic (PV) cells and modules are often rated in terms of a set of standard reporting conditions defined by a temperature, spectral irradiance, and total irradiance. Because PV devices operates over a wide range of temperatures and irradiances, the temperature and irradiance related behavior must be known. This paper surveys the temperature dependence of crystalline and thin-film, state-of-the-art, research-size cells, modules, and systems measured by a variety of methods. The various error sources and measurement methods that contribute to cause differences in the temperature coefficient for a given cell or module measured with various methods are discussed.

  11. Temperature dependence of photovoltaic cells, modules, and systems

    SciTech Connect

    Emery, K.; Burdick, J.; Caiyem, Y.

    1996-09-01

    Photovoltaic (PV) cells and modules are often rated in terms of a set of standard reporting conditions defined by a temperature, spectral irradiance, and total irradiance. Because PV devices operate over a wide range of temperatures and irradiances, the temperature and irradiance related behavior must be known. This paper surveys the temperature dependence of crystalline and thin-film, state-of-the-art, research-size cells, modules, and systems measured by a variety of methods. The various error sources and measurement methods that contribute to cause differences in the temperature coefficient for a given cell or module measured with various methods are discussed.

  12. Advanced Electrophysiologic Mapping Systems

    PubMed Central

    2006-01-01

    Executive Summary Objective To assess the effectiveness, cost-effectiveness, and demand in Ontario for catheter ablation of complex arrhythmias guided by advanced nonfluoroscopy mapping systems. Particular attention was paid to ablation for atrial fibrillation (AF). Clinical Need Tachycardia Tachycardia refers to a diverse group of arrhythmias characterized by heart rates that are greater than 100 beats per minute. It results from abnormal firing of electrical impulses from heart tissues or abnormal electrical pathways in the heart because of scars. Tachycardia may be asymptomatic, or it may adversely affect quality of life owing to symptoms such as palpitations, headaches, shortness of breath, weakness, dizziness, and syncope. Atrial fibrillation, the most common sustained arrhythmia, affects about 99,000 people in Ontario. It is associated with higher morbidity and mortality because of increased risk of stroke, embolism, and congestive heart failure. In atrial fibrillation, most of the abnormal arrhythmogenic foci are located inside the pulmonary veins, although the atrium may also be responsible for triggering or perpetuating atrial fibrillation. Ventricular tachycardia, often found in patients with ischemic heart disease and a history of myocardial infarction, is often life-threatening; it accounts for about 50% of sudden deaths. Treatment of Tachycardia The first line of treatment for tachycardia is antiarrhythmic drugs; for atrial fibrillation, anticoagulation drugs are also used to prevent stroke. For patients refractory to or unable to tolerate antiarrhythmic drugs, ablation of the arrhythmogenic heart tissues is the only option. Surgical ablation such as the Cox-Maze procedure is more invasive. Catheter ablation, involving the delivery of energy (most commonly radiofrequency) via a percutaneous catheter system guided by X-ray fluoroscopy, has been used in place of surgical ablation for many patients. However, this conventional approach in catheter ablation

  13. Generic solar photovoltaic system dynamic simulation model specification

    SciTech Connect

    Ellis, Abraham; Behnke, Michael Robert; Elliott, Ryan Thomas

    2013-10-01

    This document is intended to serve as a specification for generic solar photovoltaic (PV) system positive-sequence dynamic models to be implemented by software developers and approved by the WECC MVWG for use in bulk system dynamic simulations in accordance with NERC MOD standards. Two specific dynamic models are included in the scope of this document. The first, a Central Station PV System model, is intended to capture the most important dynamic characteristics of large scale (> 10 MW) PV systems with a central Point of Interconnection (POI) at the transmission level. The second, a Distributed PV System model, is intended to represent an aggregation of smaller, distribution-connected systems that comprise a portion of a composite load that might be modeled at a transmission load bus.

  14. Technical aspects of future photovoltaic-power systems

    NASA Astrophysics Data System (ADS)

    Jones, G. J.

    Future photovoltaic systems which will need to be designed to increase acceptance by the potential system owner and the host utility are discussed. The systems will maximize their output of high signal quality electricity to the utility through a safe and controlled interconnection, while minimizing the total cost. These systems will emphasize the use of modular array field designs and state of the art power conditioning equipment in all applications and tracking collectors wherever practical. The systems will be designed as a supplier of energy to the utility and only in the residential case will PV be colocated with a load. The major remaining hardware developments necessary to obtain these systems are the modular residential array design, modular tracking flat panel field development, and central station power conditioning definition.

  15. System Advisor Model: Flat Plate Photovoltaic Performance Modeling Validation Report

    SciTech Connect

    Freeman, J.; Whitmore, J.; Kaffine, L.; Blair, N.; Dobos, A. P.

    2013-12-01

    The System Advisor Model (SAM) is a free software tool that performs detailed analysis of both system performance and system financing for a variety of renewable energy technologies. This report provides detailed validation of the SAM flat plate photovoltaic performance model by comparing SAM-modeled PV system generation data to actual measured production data for nine PV systems ranging from 75 kW to greater than 25 MW in size. The results show strong agreement between SAM predictions and field data, with annualized prediction error below 3% for all fixed tilt cases and below 8% for all one axis tracked cases. The analysis concludes that snow cover and system outages are the primary sources of disagreement, and other deviations resulting from seasonal biases in the irradiation models and one axis tracking issues are discussed in detail.

  16. Advanced drilling systems study.

    SciTech Connect

    Pierce, Kenneth G.; Livesay, Billy Joe; Finger, John Travis

    1996-05-01

    This report documents the results of a study of advanced drilling concepts conducted jointly for the Natural Gas Technology Branch and the Geothermal Division of the U.S. Department of Energy. A number of alternative rock cutting concepts and drilling systems are examined. The systems cover the range from current technology, through ongoing efforts in drilling research, to highly speculative concepts. Cutting mechanisms that induce stress mechanically, hydraulically, and thermally are included. All functions necessary to drill and case a well are considered. Capital and operating costs are estimated and performance requirements, based on comparisons of the costs for alternative systems to conventional drilling technology, are developed. A number of problems common to several alternatives and to current technology are identified and discussed.

  17. The value of residential photovoltaic systems: A comprehensive assessment

    NASA Technical Reports Server (NTRS)

    Borden, C. S.

    1983-01-01

    Utility-interactive photovoltaic (PV) arrays on residential rooftops appear to be a potentially attractive, large-scale application of PV technology. Results of a comprehensive assessment of the value (i.e., break-even cost) of utility-grid connected residential photovoltaic power systems under a variety of technological and economic assumptions are presented. A wide range of allowable PV system costs are calculated for small (4.34 kW (p) sub ac) residential PV systems in various locales across the United States. Primary factor in this variation are differences in local weather conditions, utility-specific electric generation capacity, fuel types, and customer-load profiles that effect purchase and sell-back rates, and non-uniform state tax considerations. Additional results from this analysis are: locations having the highest insolation values are not necessary the most economically attractive sites; residential PV systems connected in parallel to the utility demonstrate high percentages of energy sold back to the grid, and owner financial and tax assumptions cause large variations in break-even costs. Significant cost reduction and aggressive resolution of potential institutional impediments (e.g., liability, standards, metering, and technical integration) are required for a residential PV marker to become a major electric-grid-connected energy-generation source.

  18. Fourth-generation photovoltaic concentrator system development

    SciTech Connect

    O`Neill, M.J.; McDanal, A.J.

    1995-10-01

    In 1991, under a contract with Sandia for the Concentrator Initiative, the ENTECH team initiated the design and development of a fourth-generation concentrator module. In 1992, Sandia also contracted with ENTECH to develop a new control and drive system for the ENTECH array. This report documents the design and development work performed under both contracts. Manufacturing processes for the new module were developed at the same time under a complementary PVMaT contract with the National Renewable Energy Laboratory. Two 100-kW power plants were deployed in 1995 in Texas using the newly developed fourth-generation concentrator technology, one at the CSW Solar Park near Ft. Davis and one at TUE Energy Park in Dallas. Technology developed under the Sandia contracts has made a successful transition from the laboratory to the production line to the field.

  19. Comparison of Photovoltaic Models in the System Advisor Model: Preprint

    SciTech Connect

    Blair, N. J.; Dobos, A. P.; Gilman, P.

    2013-08-01

    The System Advisor Model (SAM) is free software developed by the National Renewable Energy Laboratory (NREL) for predicting the performance of renewable energy systems and analyzing the financial feasibility of residential, commercial, and utility-scale grid-connected projects. SAM offers several options for predicting the performance of photovoltaic (PV) systems. The model requires that the analyst choose from three PV system models, and depending on that choice, possibly choose from three module and two inverter component models. To obtain meaningful results from SAM, the analyst must be aware of the differences between the model options and their applicability to different modeling scenarios. This paper presents an overview the different PV model options and presents a comparison of results for a 200-kW system using different model options.

  20. Design description of the Schuchuli Village photovoltaic power system

    NASA Astrophysics Data System (ADS)

    Ratajczak, A. F.; Vasicek, R. W.; Delombard, R.

    1981-05-01

    A stand alone photovoltaic (PV) power system for the village of Schuchuli (Gunsight), Arizona, on the Papago Indian Reservation is a limited energy, all 120 V (d.c.) system to which loads cannot be arbitrarily added and consists of a 3.5 kW (peak) PV array, 2380 ampere-hours of battery storage, an electrical equipment building, a 120 V (d.c.) electrical distribution network, and equipment and automatic controls to provide control power for pumping water into an existing water system; operating 15 refrigerators, a clothes washing machine, a sewing machine, and lights for each of the homes and communal buildings. A solar hot water heater supplies hot water for the washing machine and communal laundry. Automatic control systems provide voltage control by limiting the number of PV strings supplying power during system operation and battery charging, and load management for operating high priority at the expense of low priority loads as the main battery becomes depleted.

  1. Photovoltaics as a terrestrial energy source. Volume 2: System value

    NASA Astrophysics Data System (ADS)

    Smith, J. L.

    1980-10-01

    Assumptions and techniques employed by the electric utility industry and other electricity planners to make estimates of the future value of photovoltaic (PV) systems interconnected with U.S. electric utilities were examined. Existing estimates of PV value and their interpretation and limitations are discussed. PV value is defined as the marginal private savings accruing to potential PV owners. For utility-owned PV systems, these values are shown to be the after-tax savings in conventional fuel and capacity displaced by the PV output. For non-utility-owned (distributed) systems, the utility's savings in fuel and capacity must first be translated through the electric rate structure (prices) to the potential PV system owner. Base-case estimates of the average value of PV systems to U.S. utilities are presented. The relationship of these results to the PV Program price goals and current energy policy is discussed; the usefulness of PV output quantity goals is also reviewed.

  2. Photovoltaics as a terrestrial energy source. Volume 2: System value

    NASA Technical Reports Server (NTRS)

    Smith, J. L.

    1980-01-01

    Assumptions and techniques employed by the electric utility industry and other electricity planners to make estimates of the future value of photovoltaic (PV) systems interconnected with U.S. electric utilities were examined. Existing estimates of PV value and their interpretation and limitations are discussed. PV value is defined as the marginal private savings accruing to potential PV owners. For utility-owned PV systems, these values are shown to be the after-tax savings in conventional fuel and capacity displaced by the PV output. For non-utility-owned (distributed) systems, the utility's savings in fuel and capacity must first be translated through the electric rate structure (prices) to the potential PV system owner. Base-case estimates of the average value of PV systems to U.S. utilities are presented. The relationship of these results to the PV Program price goals and current energy policy is discussed; the usefulness of PV output quantity goals is also reviewed.

  3. Design description of the Schuchuli Village photovoltaic power system

    NASA Technical Reports Server (NTRS)

    Ratajczak, A. F.; Vasicek, R. W.; Delombard, R.

    1981-01-01

    A stand alone photovoltaic (PV) power system for the village of Schuchuli (Gunsight), Arizona, on the Papago Indian Reservation is a limited energy, all 120 V (d.c.) system to which loads cannot be arbitrarily added and consists of a 3.5 kW (peak) PV array, 2380 ampere-hours of battery storage, an electrical equipment building, a 120 V (d.c.) electrical distribution network, and equipment and automatic controls to provide control power for pumping water into an existing water system; operating 15 refrigerators, a clothes washing machine, a sewing machine, and lights for each of the homes and communal buildings. A solar hot water heater supplies hot water for the washing machine and communal laundry. Automatic control systems provide voltage control by limiting the number of PV strings supplying power during system operation and battery charging, and load management for operating high priority at the expense of low priority loads as the main battery becomes depleted.

  4. Smart integrated energy monitoring and management system for standalone photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Abou-Elnour, Ali; Murad, Fahd S.; Al-Tayasna, Ibrahim S.; Abo-Elnor, Ossama

    2013-04-01

    In the present work, a computer based smart integrated energy monitoring and management system for standalone photovoltaic systems is designed and implemented. Monitoring, controlling, and recording features are fully obtained in the present system using an efficient programming environment. All required data are monitored as real-time data therefore the system status is continuously evaluated and decisions are made to take immediate actions. The energy consumption of different appliances are automatically controlled and optimized using a hierarchical self adaptive algorithm based on input data and real-time information provided by the system sensors. The proposed system is successfully implemented for photovoltaic modules under realistic operating conditions.

  5. Material Science for High-Efficiency Photovoltaics: From Advanced Optical Coatings to Cell Design for High-Temperature Applications

    NASA Astrophysics Data System (ADS)

    Perl, Emmett Edward

    Solar cells based on III-V compound semiconductors are ideally suited to convert solar energy into electricity. The highest efficiency single-junction solar cells are made of gallium arsenide, and have attained an efficiency of 28.8%. Multiple III-V materials can be combined to construct multijunction solar cells, which have reached record efficiencies greater than 45% under concentration. III-V solar cells are also well suited to operate efficiently at elevated temperatures, due in large part to their high material quality. These properties make III-V solar cells an excellent choice for use in concentrator systems. Concentrator photovoltaic systems have attained module efficiencies that exceed 40%, and have the potential to reach the lowest levelized cost of electricity in sunny places like the desert southwest. Hybrid photovoltaic-thermal solar energy systems can utilize high-temperature III-V solar cells to simultaneously achieve dispatchability and a high sunlight-to-electricity efficiency. This dissertation explores material science to advance the state of III-V multijunction solar cells for use in concentrator photovoltaic and hybrid photovoltaic-thermal solar energy systems. The first half of this dissertation describes work on advanced optical designs to improve the efficiency of multijunction solar cells. As multijunction solar cells move to configurations with four or more subcells, they utilize a larger portion of the solar spectrum. Broadband antireflection coatings are essential to realizing efficiency gains for these state-of-the-art cells. A hybrid design consisting of antireflective nanostructures placed on top of multilayer interference-based optical coatings is developed. Antireflection coatings that utilize this hybrid approach yield unparalleled performance, minimizing reflection losses to just 0.2% on sapphire and 0.6% on gallium nitride for 300-1800nm light. Dichroic mirrors are developed for bonded 5-junction solar cells that utilize InGaN as

  6. Space station experiment definition: Advanced power system test bed

    NASA Technical Reports Server (NTRS)

    Pollard, H. E.; Neff, R. E.

    1986-01-01

    A conceptual design for an advanced photovoltaic power system test bed was provided and the requirements for advanced photovoltaic power system experiments better defined. Results of this study will be used in the design efforts conducted in phase B and phase C/D of the space station program so that the test bed capabilities will be responsive to user needs. Critical PV and energy storage technologies were identified and inputs were received from the idustry (government and commercial, U.S. and international) which identified experimental requirements. These inputs were used to develop a number of different conceptual designs. Pros and cons of each were discussed and a strawman candidate identified. A preliminary evolutionary plan, which included necessary precursor activities, was established and cost estimates presented which would allow for a successful implementation to the space station in the 1994 time frame.

  7. Distributed generation system using wind/photovoltaic/fuel cell

    NASA Astrophysics Data System (ADS)

    Buasri, Panhathai

    This dissertation investigates the performance and the operation of a distributed generation (DG) power system using wind/photovoltaic/fuel cell (W/PV/FC). The power system consists of a 2500 W photovoltaic array subsystem, a 500 W proton exchange membrane fuel cell (PEMFC) stack subsystem, 300 W wind turbine, 500 W wind turbine, and 1500 W wind energy conversion subsystems. To extract maximum power from the PV, a maximum power point tracker was designed and fabricated. A 4 kW single phase inverter was used to convert the DC voltage to AC voltage; also a 44 kWh battery bank was used to store energy and prevent fluctuation of the power output of the DG system. To connect the fuel cell to the batteries, a DC/DC controller was designed and fabricated. To monitor and study the performance of the DG system under variable conditions, a data acquisition system was designed and installed. The fuel cell subsystem performance was evaluated under standalone operation using a variable resistance and under interactive mode, connected to the batteries. The manufacturing data and the experimental data were used to develop an electrical circuit model to the fuel cell. Furthermore, harmonic analysis of the DG system was investigated. For an inverter, the AC voltage delivered to the grid changed depending on the time, load, and electronic equipment that was connected. The quality of the DG system was evaluated by investigating the harmonics generated by the power electronics converters. Finally, each individual subsystem of the DG system was modeled using the neuro-fuzzy approach. The model was used to predict the performance of the DG system under variable conditions, such as passing clouds and wind gust conditions. The steady-state behaviors of the model were validated by the experimental results under different operating conditions.

  8. Deploying High Penetration Photovoltaic Systems: A Case Study

    SciTech Connect

    Coddington, M. H.; Baca, D.; Kroposki, B. D.; Basso, T.

    2011-01-01

    Photovoltaic (PV) system capacity penetration, or simply 'penetration,' is often defined as the rated power output of the aggregate PV systems on a distribution circuit segment divided by the peak load of that circuit segment. Industry experts agree that a single value defining high penetration is not universally applicable. However, it is generally agreed that a conservative value to designate high penetration is the condition when the ratio of aggregate PV systems ratings to peak load exceeds 15%. This case study illustrates the case of a distribution feeder which is able to accommodate a traditional capacity penetration level of 47%, and perhaps more. New maximum penetration levels need to be defined and verified and enhanced definitions for penetration on a distribution circuit need to be developed. The new penetration definitions and studies will help utility engineers, system developers, and regulatory agencies better agree what levels of PV deployment can be attained without jeopardizing the reliability and power quality of a circuit.

  9. Control and performance of a photovoltaic-thermal energy system

    NASA Astrophysics Data System (ADS)

    Bazques, E. O.

    1983-12-01

    The control of a photovoltaic/thermal energy (PV/T) system in general and optimization of performance in particular through use of modern (state space) control methods, stochastic weather inputs, and second law of thermodynamics analysis is addressed. Significant improvement in system performance is noted using optimal control when compared to conventional on/off, multilevel, or proportional controllers for deterministic weather forcing functions. Optimal system control, analyzed first through use of Pontryagin's Minimum Principle and then implemented by specification of a quadratic performance index and solution of matrix Riccati equations, is shown to be a viable and useful strategy for these hybrid systems. Stochastic weather techniques which incorporate temperature/insolation probability density matrices and least square constants are found to be a valid method for reducing simulation requirements as long as weather persistence effects are taken into account through use of information derived from Markov transition matrices.

  10. Fire hazard and other safety concerns of photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Dhere, Neelkanth G.; Shiradkar, Narendra S.

    2012-01-01

    Photovoltaic (PV) modules are usually considered safe and reliable. But in case of grid-connected PV systems that are becoming popular, the issue of fire safety of PV modules is becoming increasingly important due to the employed high voltages of 600 to 1000 V. The two main factors, i.e., open circuiting of the dc circuit and of the bypass diodes and ground faults that are responsible for the fire in the PV systems, have been discussed in detail along with numerous real life examples. Recommendations are provided for preventing the fire hazards such as designing the PV array mounting system to minimize the chimney effect, having proper bypass and blocking diodes, and interestingly, having an ungrounded PV system.

  11. Distributed photovoltaic systems: Utility interface issues and their present status

    NASA Technical Reports Server (NTRS)

    Hassan, M.; Klein, J.

    1981-01-01

    Major technical issues involving the integration of distributed photovoltaics (PV) into electric utility systems are defined and their impacts are described quantitatively. An extensive literature search, interviews, and analysis yielded information about the work in progress and highlighted problem areas in which additional work and research are needed. The findings from the literature search were used to determine whether satisfactory solutions to the problems exist or whether satisfactory approaches to a solution are underway. It was discovered that very few standards, specifications, or guidelines currently exist that will aid industry in integrating PV into the utility system. Specific areas of concern identified are: (1) protection, (2) stability, (3) system unbalance, (4) voltage regulation and reactive power requirements, (5) harmonics, (6) utility operations, (7) safety, (8) metering, and (9) distribution system planning and design.

  12. Distributed photovoltaic systems: Utility interface issues and their present status

    NASA Astrophysics Data System (ADS)

    Hassan, M.; Klein, J.

    1981-09-01

    Major technical issues involving the integration of distributed photovoltaics (PV) into electric utility systems are defined and their impacts are described quantitatively. An extensive literature search, interviews, and analysis yielded information about the work in progress and highlighted problem areas in which additional work and research are needed. The findings from the literature search were used to determine whether satisfactory solutions to the problems exist or whether satisfactory approaches to a solution are underway. It was discovered that very few standards, specifications, or guidelines currently exist that will aid industry in integrating PV into the utility system. Specific areas of concern identified are: (1) protection, (2) stability, (3) system unbalance, (4) voltage regulation and reactive power requirements, (5) harmonics, (6) utility operations, (7) safety, (8) metering, and (9) distribution system planning and design.

  13. Sampling and Filtering in Photovoltaic System Performance Monitoring

    SciTech Connect

    Driesse, Anton; Stein, Joshua S.; Riley, Daniel M.; Carmignani, Craig K.

    2014-10-01

    The performance of photovoltaic systems must be monitored accurately to ensure profitable long-term operation. The most important signals to be measured—irradiance and temperature, as well as power, current and voltage on both DC and AC sides of the system—contain rapid fluctuations that are not observable by typical monitoring systems. Nevertheless these fluctuations can affect the accuracy of the data that are stored. This report closely examines the main signals in one operating PV system, which were recorded at 2000 samples per second. It analyzes the characteristics and causes of the rapid fluctuations that are found, such as line-frequency harmonics, perturbations from anti-islanding detection, MPPT searching action and others. The operation of PV monitoring systems is then simulated using a wide range of sampling intervals, archive intervals and filtering options to assess how these factors influence data accuracy. Finally several potential sources of error are discussed with real-world examples.

  14. Photovoltaic-wind hybrid system for permanent magnet DC motor

    NASA Astrophysics Data System (ADS)

    Nasir, M. N. M.; Lada, M. Y.; Baharom, M. F.; Jaafar, H. I.; Ramani, A. N.; Sulaima, M. F.

    2015-05-01

    Hybrid system of Photovoltaic (PV) - Wind turbine (WT) generation has more advantages and reliable compared to PV or wind turbine system alone. The aim of this paper is to model and design hybrid system of PV-WT supplying 100W permanent-magnet dc motor. To achieve the objective, both of PV and WT are connected to converter in order to get the same source of DC supply. Then both sources were combined and straightly connected to 100W permanent magnet dc motor. All the works in this paper is only applied in circuit simulator by using Matlab Simulink. The output produced from each converter is expected to be suit to the motor specification. The output produced from each renewable energy system is as expected to be high as it can support the motor if one of them is breakdown

  15. The El Paso electric 20-kilowatt photovoltaic system

    NASA Astrophysics Data System (ADS)

    Risser, V. V.; Durand, S.

    1982-01-01

    Features and operational characteristics of a 20 kW flat plate photovoltaic power system are described. The system powers computers which control a combined cycle 190 MW power plant. Performance has been an average of 93 kWh/day, 6.05% efficiency, and at an average cell temperature of 22 C from Dec. 1980 to Sept. 1981. The array comprises 279 sq m area, 64 panels, 6 subarrays for subsystem shorting if necessary, and fuses set at 250 V with a reaction time of 10 microsec. Testing procedures are outlined, including data acquisition, weather monitoring, operation in cloudy periods, and fault isolation modes. Maintenance has been dominated by upkeep of the data acquisition system, and it is noted that significant reductions in all maintenance would have results in only minor reductions in overall system performance

  16. SOLERAS: Photovoltaic power systems project. Module failure analysis

    NASA Astrophysics Data System (ADS)

    Huraib, F. S.; Imamura, M. S.; Salim, A. A.; Rao, N.

    1984-10-01

    The SOLERAS Photovoltaic Power System (PVPS) became operational in September 1981. The system has operated satisfactorily and has experienced very little downtime. Early in 1983 some degradation in the photovoltaic (PV) field performance was detected. A series of current voltage (I-V) tests and other analyses eventually uncovered a number of PV modules that have resulted in open circuit type failure in the four cell group, or a half module. As of August 1984, the estimated number of these defective modules in the PV field was 152. In addition, there are a total of 188 defective modules in the storage warehouse, resulting in a total of 340 modules that need repairs. At the current rate of failures (seven half modules per month), an additional 112 modules would be defective by the end of January 1986, resulting in 412 defective modules. This report presents the results of the failure analysis performed during the past several months on the open circuit modules. Background information as related to the module failures and the effects of such failures on the overall PV field power output are provided. In addition, a plan to continue the monitoring of the rate of failure and analyzing the failure mechanisms is presented.

  17. The Mars climate for a photovoltaic system operation

    NASA Technical Reports Server (NTRS)

    Appelbaum, Joseph; Flood, Dennis J.

    1989-01-01

    Detailed information on the climatic conditions on Mars are very desirable for the design of photovoltaic systems for establishing outposts on the Martian surface. The distribution of solar insolation (global, direct and diffuse) and ambient temperature is addressed. This data are given at the Viking lander's locations and can also be used, to a first approximation, for other latitudes. The insolation data is based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation. The ambient temperature (diurnal and yearly distribution) is based on direct measurements with a thermocouple at 1.6 m above the ground at the Viking lander locations. The insolation and ambient temperature information are short term data. New information about Mars may be forthcoming in the future from new analysis of previously collected data or from future flight missions. The Mars climate data for photovoltaic system operation will thus be updated accordingly.

  18. System tradeoffs in siting a solar photovoltaic material recovery infrastructure.

    PubMed

    Goe, Michele; Gaustad, Gabrielle; Tomaszewski, Brian

    2015-09-01

    The consumption and disposal of rare and hazardous metals contained in electronics and emerging technologies such as photovoltaics increases the material complexity of the municipal waste stream. Developing effective waste policies and material recovery systems is required to inhibit landfilling of valuable and finite resources. This work developed a siting and waste infrastructure configuration model to inform the management and recovery of end-of-life photovoltaics. This model solves the siting and waste location-allocation problem for a New York State case study by combining multi-criteria decision methods with spatial tools, however this methodology is generalizable to any geographic area. For the case study, the results indicate that PV installations are spatially statistically significant (i.e., clustered). At least 9 sites, which are co-located with landfills and current MRFs, were 'highly' suitable for siting according to our criteria. After combining criteria in an average weighted sum, 86% of the study area was deemed unsuitable for siting while less than 5% is characterized as highly suitable. This method implicitly prioritized social and environmental concerns and therefore, these concerns accounted for the majority of siting decisions. As we increased the priority of economic criteria, the likelihood of siting near ecologically sensitive areas such as coastline or socially vulnerable areas such as urban centers increased. The sensitivity of infrastructure configurations to land use and waste policy are analyzed. The location allocation model results suggest current tip fees are insufficient to avoid landfilling of photovoltaics. Scenarios where tip fees were increased showed model results where facilities decide to adopt limited recycling technologies that bypass compositionally complex materials; a result with strong implications for global PV installations as well as other waste streams. We suggest a multi-pronged approach that lowers technology cost

  19. Modeling, control, and dispatch of photovoltaic-based power distribution systems

    NASA Astrophysics Data System (ADS)

    Carrasco, Miguel

    Small-scale generators, also called distributed generators (DGs), are primed to play a central role in future distribution systems. If properly integrated, DGs present two main advantages: (i) they help decongest existing transmission grids; and (ii) CO2 emissions are reduced since most DGs are based on renewables like wind and solar. Their integration into distribution systems is one of the main challenges the power industry will be facing in the coming years. Photovoltaic (PV) power generation represents a key technology for realizing the DG concept. In this dissertation, technical solutions are developed that enable an increased penetration of PV systems, while improving the efficiency, reliability, and power quality of power distribution grids. The presented research spans from PV array modeling, parameter identification and estimation methods, through advanced control strategies for the power electronic interfaces, to system--level optimal dispatch strategies. Simulation-based and experimental validation results show the performance of the proposed techniques.

  20. Photovoltaics in the context of off-grid small power systems

    NASA Astrophysics Data System (ADS)

    Gabriel, A.; de Ruyter van Steveninck, A. W.

    Practical criteria which determine the cost effectiveness in different applications of stand-alone off-grid continuous power systems up to 20 kW are examined. The analysis is limited to systems based on internal combustion engines and photovoltaic systems. It is shown that for nonmobile continuous power systems with offtakes above 20-25%, photovoltaic cost parity with 5 kW diesel systems is expected to occur in the second half of this decade or in the first half of the next decade, depending mainly on the fuel cost to the consumer. Larger diesel systems show improved costs due to scale benefits which are not available to photovoltaic systems.

  1. Feasibility Study for Photovoltaics, Wind, solar Hot Water and Hybrid Systems

    SciTech Connect

    Hooks, Ronald; Montoya, Valerie

    2008-03-26

    Southwestern Indian Polytechnic Institute (SIPI) located in Albuquerque New Mexico is a community college that serves American Indians and Alaska Natives. SIPI’s student body represents over 100 Native American Tribes. SIPI completed a renewable energy feasibility study program and established renewable energy hardware on the SIPI campus, which supplements and creates an educational resource to teach renewable energy courses. The SIPI campus is located, and has as student origins, areas, in which power is an issue in remote reservations. The following hardware was installed and integrated into the campus facilities: small wind turbine, large photovoltaic array that is grid-connected, two photovoltaic arrays, one thin film type, and one polycrystalline type, one dual-axis active tracker and one passive tracker, a hot air system for heating a small building, a portable hybrid photovoltaic system for remote power, and a hot water system to preheat water used in the SIPI Child Care facility. Educational curriculum has been developed for two renewable energy courses one being the study of energy production and use, and especially the roles renewable energy forms like solar, wind, geothermal, hydro, and biomass plays, and the second course being a more advanced in-depth study of renewable energy system design, maintenance, installation, and applications. Both courses rely heavily on experiential learning techniques so that installed renewable energy hardware is continuously utilized in hand-on laboratory activities and are part of the Electronics program of studies. Renewable energy technologies and science has also been included in other SIPI programs of study such as Environmental Science, Natural Resources, Agriculture, Engineering, Network Management, and Geospatial Technology.

  2. Reliability assessment for components of large scale photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Ahadi, Amir; Ghadimi, Noradin; Mirabbasi, Davar

    2014-10-01

    Photovoltaic (PV) systems have significantly shifted from independent power generation systems to a large-scale grid-connected generation systems in recent years. The power output of PV systems is affected by the reliability of various components in the system. This study proposes an analytical approach to evaluate the reliability of large-scale, grid-connected PV systems. The fault tree method with an exponential probability distribution function is used to analyze the components of large-scale PV systems. The system is considered in the various sequential and parallel fault combinations in order to find all realistic ways in which the top or undesired events can occur. Additionally, it can identify areas that the planned maintenance should focus on. By monitoring the critical components of a PV system, it is possible not only to improve the reliability of the system, but also to optimize the maintenance costs. The latter is achieved by informing the operators about the system component's status. This approach can be used to ensure secure operation of the system by its flexibility in monitoring system applications. The implementation demonstrates that the proposed method is effective and efficient and can conveniently incorporate more system maintenance plans and diagnostic strategies.

  3. Field Performance of Photovoltaic Systems in the Tucson Desert

    NASA Astrophysics Data System (ADS)

    Orsburn, Sean; Brooks, Adria; Cormode, Daniel; Greenberg, James; Hardesty, Garrett; Lonij, Vincent; Salhab, Anas; St. Germaine, Tyler; Torres, Gabe; Cronin, Alexander

    2011-10-01

    At the Tucson Electric Power (TEP) solar test yard, over 20 different grid-connected photovoltaic (PV) systems are being tested. The goal at the TEP solar test yard is to measure and model real-world performance of PV systems and to benchmark new technologies such as holographic concentrators. By studying voltage and current produced by the PV systems as a function of incident irradiance, and module temperature, we can compare our measurements of field-performance (in a harsh desert environment) to manufacturer specifications (determined under laboratory conditions). In order to measure high-voltage and high-current signals, we designed and built reliable, accurate sensors that can handle extreme desert temperatures. We will present several benchmarks of sensors in a controlled environment, including shunt resistors and Hall-effect current sensors, to determine temperature drift and accuracy. Finally we will present preliminary field measurements of PV performance for several different PV technologies.

  4. Analysis of Photovoltaic System Energy Performance Evaluation Method

    SciTech Connect

    Kurtz, S.; Newmiller, J.; Kimber, A.; Flottemesch, R.; Riley, E.; Dierauf, T.; McKee, J.; Krishnani, P.

    2013-11-01

    Documentation of the energy yield of a large photovoltaic (PV) system over a substantial period can be useful to measure a performance guarantee, as an assessment of the health of the system, for verification of a performance model to then be applied to a new system, or for a variety of other purposes. Although the measurement of this performance metric might appear to be straight forward, there are a number of subtleties associated with variations in weather and imperfect data collection that complicate the determination and data analysis. A performance assessment is most valuable when it is completed with a very low uncertainty and when the subtleties are systematically addressed, yet currently no standard exists to guide this process. This report summarizes a draft methodology for an Energy Performance Evaluation Method, the philosophy behind the draft method, and the lessons that were learned by implementing the method.

  5. Modular photovoltaic stand-alone systems: Phase 1

    NASA Technical Reports Server (NTRS)

    Naff, G. J.; Marshall, N. A.

    1983-01-01

    A family of modular stand-alone power systems that covered the range in power level from 1 kw to 14 kw was developed. Products within this family were required to be easily adaptable to different environments and applications, and were to be both reliable and cost effective. Additionally, true commonality in hardware was to be exploited, and unnecessary recurrence of design and development costs were to be minimized; thus improving hardware availability. Assurance of compatibility with large production runs, was also an underlying program goal. A secondary objective was to compile, evaluate, and determine the economic and technical status of available, and potentially available, technology options associated with the balance of systems (BOS) for stand-along photovoltaic (PV) power systems. The secondary objective not only directly supported the primary but additionally contributed to the definition and implementation of the BOS cost reduction plan.

  6. Management of excess energy in autonomous photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Ofry, E.; Singer, S.

    1983-01-01

    The installation and use of a variable complementary load for absorbing electrical energy generated by photovoltaic cells (PV) in excess of that needed by the normal load or the battery storage system is described. The excesses are expected to occur due to periodic variations in the solar input during the year. Using the 48-panel PV array at Tel Aviv University as an example, it is shown that overproduction of power by only a few percent per day can lead to degraded battery performance, thereby requiring a quick discharge path once the battery bank is fully charged. Connecting the circuit to heat radiators, air conditioners, or ventilation devices to cool the battery system is demonstrated to avoid the battery overheating problem which would arise from overcharging. A block diagram is furnished of a connection to a fan to provide ventilation around the battery system.

  7. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2004-10-12

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  8. Advanced Containment System

    DOEpatents

    Kostelnik, Kevin M.; Kawamura, Hideki; Richardson, John G.; Noda, Masaru

    2005-05-24

    An advanced containment system for containing buried waste and associated leachate. A trench is dug on either side of the zone of interest containing the buried waste so as to accommodate a micro tunnel boring machine. A series of small diameter tunnels are serially excavated underneath the buried waste. The tunnels are excavated by the micro tunnel boring machine at a consistent depth and are substantially parallel to each other. As tunneling progresses, steel casing sections are connected end to end in the excavated portion of the tunnel so that a steel tube is formed. Each casing section has complementary interlocking structure running its length that interlocks with complementary interlocking structure on the adjacent casing section. Thus, once the first tube is emplaced, placement of subsequent tubes is facilitated by the complementary interlocking structure on the adjacent, previously placed, casing sections.

  9. Optical Frequency Optimization of a High Intensity Laser Power Beaming System Utilizing VMJ Photovoltaic Cells

    NASA Technical Reports Server (NTRS)

    Raible, Daniel E.; Dinca, Dragos; Nayfeh, Taysir H.

    2012-01-01

    An effective form of wireless power transmission (WPT) has been developed to enable extended mission durations, increased coverage and added capabilities for both space and terrestrial applications that may benefit from optically delivered electrical energy. The high intensity laser power beaming (HILPB) system enables long range optical 'refueling" of electric platforms such as micro unmanned aerial vehicles (MUAV), airships, robotic exploration missions and spacecraft platforms. To further advance the HILPB technology, the focus of this investigation is to determine the optimal laser wavelength to be used with the HILPB receiver, which utilizes vertical multi-junction (VMJ) photovoltaic cells. Frequency optimization of the laser system is necessary in order to maximize the conversion efficiency at continuous high intensities, and thus increase the delivered power density of the HILPB system. Initial spectral characterizations of the device performed at the NASA Glenn Research Center (GRC) indicate the approximate range of peak optical-to-electrical conversion efficiencies, but these data sets represent transient conditions under lower levels of illumination. Extending these results to high levels of steady state illumination, with attention given to the compatibility of available commercial off-the-shelf semiconductor laser sources and atmospheric transmission constraints is the primary focus of this paper. Experimental hardware results utilizing high power continuous wave (CW) semiconductor lasers at four different operational frequencies near the indicated band gap of the photovoltaic VMJ cells are presented and discussed. In addition, the highest receiver power density achieved to date is demonstrated using a single photovoltaic VMJ cell, which provided an exceptionally high electrical output of 13.6 W/sq cm at an optical-to-electrical conversion efficiency of 24 percent. These results are very promising and scalable, as a potential 1.0 sq m HILPB receiver of

  10. 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.

  11. Advances in Single and Multijunction III-V Photovoltaics on Silicon for Space Power

    NASA Technical Reports Server (NTRS)

    Wilt, David M.; Fitzgerald, Eugene A.; Ringel, Steven A.

    2005-01-01

    A collaborative research effort at MIT, Ohio State University and NASA has resulted in the demonstration of record quality gallium arsenide (GaAs) based single junction photovoltaic devices on silicon (Si) substrates. The ability to integrate highly efficient, radiation hard III-V based devices on silicon offers the potential for dramatic reductions in cell mass (approx.2x) and increases in cell area. Both of these improvements offer the potential for dramatic reductions in the cost of on-orbit electrical power. Recently, lattice matched InGaP/GaAs and metamorphic InGaP/InGaAs dual junction solar cells were demonstrated by MBE and OMVPE, respectively. Single junction GaAs on Si devices have been integrated into a space flight experiment (MISSES), scheduled to be launched to the International Space Station in March of 2005. I-V performance data from the GaAs/Si will be collected on-orbit and telemetered to ground stations daily. Microcracks in the GaAs epitaxial material, generated because of differences in the thermal expansion coefficient between GaAs and Si, are of concern in the widely varying thermal environment encountered in low Earth orbit. Ground based thermal life cycling (-80 C to + 80 C) equivalent to 1 year in LEO has been conducted on GaAs/Si devices with no discernable degradation in device performance, suggesting that microcracks may not limit the ability to field GaAs/Si in harsh thermal environments. Recent advances in the development and testing of III-V photovoltaic devices on Si will be presented.

  12. A Novel Open-Loop Tracking Strategy for Photovoltaic Systems

    PubMed Central

    Alexandru, Cătălin

    2013-01-01

    This paper approaches a dual-axis equatorial tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. The innovative aspect in the solar tracker design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with the motor torques whose computation is based on the dynamic model of the mechanical structure on which external forces act. The daily and elevation angles of the PV module represent the input parameters in the mechanical device, while the outputs transmitted to the controller are the motor torques. The controller tuning is approached by a parametric optimization process, using design of experiments and response surface methodology techniques, in a multiple regression. The simulation and experimental results demonstrate the operational performance of the tracking system. PMID:24327803

  13. Verification of Fresnel lens in high concentration photovoltaic system

    NASA Astrophysics Data System (ADS)

    Wei, An-Chi; Sze, Jyh-Rou; Chern, Jyh-Long

    2012-10-01

    An approach using micro lens arrays to confine the cone angle of light source in a solar simulator has been proposed to verify the Fresnel lens in a high concentration photovoltaic (HCPV) system. Compared with other three prior arts by the computer simulation, the proposed method had the characteristics of the better approximation to the direct normal insolation and the low cost. Also, to ensure the erection of the evaluation system, the tolerance of lens alignment has been analyzed. The results showed that to maintain at least the 50% of the maximum luminous flux incident on the solar cell, the transverse and longitudinal tolerances of ±1.4 mm and ±4 mm, respectively, were required.

  14. A novel open-loop tracking strategy for photovoltaic systems.

    PubMed

    Alexandru, Cătălin

    2013-01-01

    This paper approaches a dual-axis equatorial tracking system that is used to increase the photovoltaic efficiency by maximizing the degree of use of the solar radiation. The innovative aspect in the solar tracker design consists in considering the tracking mechanism as a perturbation for the DC motors. The goal is to control the DC motors, which are perturbed with the motor torques whose computation is based on the dynamic model of the mechanical structure on which external forces act. The daily and elevation angles of the PV module represent the input parameters in the mechanical device, while the outputs transmitted to the controller are the motor torques. The controller tuning is approached by a parametric optimization process, using design of experiments and response surface methodology techniques, in a multiple regression. The simulation and experimental results demonstrate the operational performance of the tracking system.

  15. Multiple exciton collection in a sensitized photovoltaic system.

    PubMed

    Sambur, Justin B; Novet, Thomas; Parkinson, B A

    2010-10-01

    Multiple exciton generation, the creation of two electron-hole pairs from one high-energy photon, is well established in bulk semiconductors, but assessments of the efficiency of this effect remain controversial in quantum-confined systems like semiconductor nanocrystals. We used a photoelectrochemical system composed of PbS nanocrystals chemically bound to TiO(2) single crystals to demonstrate the collection of photocurrents with quantum yields greater than one electron per photon. The strong electronic coupling and favorable energy level alignment between PbS nanocrystals and bulk TiO(2) facilitate extraction of multiple excitons more quickly than they recombine, as well as collection of hot electrons from higher quantum dot excited states. Our results have implications for increasing the efficiency of photovoltaic devices by avoiding losses resulting from the thermalization of photogenerated carriers.

  16. Optimal charge control strategies for stationary photovoltaic battery systems

    NASA Astrophysics Data System (ADS)

    Li, Jiahao; Danzer, Michael A.

    2014-07-01

    Battery systems coupled to photovoltaic (PV) modules for example fulfill one major function: they locally decouple PV generation and consumption of electrical power leading to two major effects. First, they reduce the grid load, especially at peak times and therewith reduce the necessity of a network expansion. And second, they increase the self-consumption in households and therewith help to reduce energy expenses. For the management of PV batteries charge control strategies need to be developed to reach the goals of both the distribution system operators and the local power producer. In this work optimal control strategies regarding various optimization goals are developed on the basis of the predicted household loads and PV generation profiles using the method of dynamic programming. The resulting charge curves are compared and essential differences discussed. Finally, a multi-objective optimization shows that charge control strategies can be derived that take all optimization goals into account.

  17. Manufacturing injection-moleded Fresnel lens parquets for point-focus concentrating photovoltaic systems

    SciTech Connect

    Peters, E.M.; Masso, J.D.

    1995-10-01

    This project involved the manufacturing of curved-faceted, injection-molded, four-element Fresnel lens parquets for concentrating photovoltaic arrays. Previous efforts showed that high-efficiency (greater than 82%) Fresnel concentrators could be injection molded. This report encompasses the mold design, molding, and physical testing of a four-lens parquet for a solar photovoltaic concentrator system.

  18. 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.

  19. Advanced hydrologic prediction system

    NASA Astrophysics Data System (ADS)

    Connelly, Brian A.; Braatz, Dean T.; Halquist, John B.; Deweese, Michael M.; Larson, Lee; Ingram, John J.

    1999-08-01

    As our Nation's population and infrastructure grow, natural disasters are becoming a greater threat to our society's stability. In an average year, inland flooding claims 133 lives and resulting property losses exceed 4.0 billion. Last year, 1997, these losses totaled 8.7 billion. Because of this blossoming threat, the National Weather Service (NWS) has requested funding within its 2000 budget to begin national implementation of the Advanced Hydrologic Prediction System (AHPS). With this system in place the NWS will be able to utilize precipitation and climate predictions to provide extended probabilistic river forecasts for risk-based decisions. In addition to flood and drought mitigation benefits, extended river forecasts will benefit water resource managers in decision making regarding water supply, agriculture, navigation, hydropower, and ecosystems. It's estimated that AHPS, if implemented nationwide, would save lives and provide $677 million per year in economic benefits. AHPS is used currently on the Des Moines River basin in Iowa and will be implemented soon on the Minnesota River basin in Minnesota. Experience gained from user interaction is leading to refined and enhanced product formats and displays. This discussion will elaborate on the technical requirements associated with AHPS implementation, its enhanced products and informational displays, and further refinements based on customer feedback.

  20. Control algorithms and computer simulation of a stand-alone photovoltaic village power system

    NASA Technical Reports Server (NTRS)

    Groumpos, P. P.; Culler, J. E.; Delombard, R.; Ratajczak, A. F.; Cull, R.

    1984-01-01

    At Stand-Alone Photovoltaic (SAPV) power systems increase in size and load diversity, the design and simulation of control subsystems takes on added importance. These SAPV systems represent 'mini utilities' with commensurate controls requirements, albeit with the added complexity of the energy source (sunlight received) being an uncontrollable variable. This paper briefly describes a stand-alone photovoltaic power/load system computerized simulation model. The model was tested against operational data from the Schuchuli stand-alone village photovoltaic system and has achieved acceptable levels of simulation accuracy. The model can be used to simulate system designs although with probable battery modification.

  1. Advanced Optical Fiber Communication Systems

    DTIC Science & Technology

    1992-08-01

    Optical Network with Physical Star Topology," Advanced Fiber Communications Technologies , Leonid G. Kazovsky... advances in the performance and capabilities of optical fiber communication systems. While some of these technologies are interrelated (for example...multi gigabit per second hybrid circuit/packet switched lightwave network ," Proc. SPIE Advanced Fiber Communications Technologies , Boston 󈨟, Sept.

  2. Designing a concentrating photovoltaic (CPV) system in adjunct with a silicon photovoltaic panel for a solar competition car

    NASA Astrophysics Data System (ADS)

    Arias-Rosales, Andrés.; Barrera-Velásquez, Jorge; Osorio-Gómez, Gilberto; Mejía-Gutiérrez, Ricardo

    2014-06-01

    Solar competition cars are a very interesting research laboratory for the development of new technologies heading to their further implementation in either commercial passenger vehicles or related applications. Besides, worldwide competitions allow the spreading of such ideas where the best and experienced teams bet on innovation and leading edge technologies, in order to develop more efficient vehicles. In these vehicles, some aspects generally make the difference such as aerodynamics, shape, weight, wheels and the main solar panels. Therefore, seeking to innovate in a competitive advantage, the first Colombian solar vehicle "Primavera", competitor at the World Solar Challenge (WSC)-2013, has implemented the usage of a Concentrating Photovoltaic (CPV) system as a complementary solar energy module to the common silicon photovoltaic panel. By harvesting sunlight with concentrating optical devices, CPVs are capable of maximizing the allowable photovoltaic area. However, the entire CPV system weight must be less harmful than the benefit of the extra electric energy generated, which in adjunct with added manufacture and design complexity, has intervened in the fact that CPVs had never been implemented in a solar car in such a scale as the one described in this work. Design considerations, the system development process and implementation are presented in this document considering both the restrictions of the context and the interaction of the CPV system with the solar car setup. The measured data evidences the advantage of using this complementary system during the competition and the potential this technology has for further developments.

  3. Microprocessor-controlled photovoltaic-array loading unit

    SciTech Connect

    Russell, D.F.

    1982-08-01

    Described is a microprocessor-controlled test system in operation at the Photovoltaics Advanced Systems Test Facility located at Sandia National Laboratories. The test system is designed to measure the total energy output of photovoltaic arrays. The theory, installation, operation, and calibration of the test system are described.

  4. Startup experience with a concentrating photovoltaic power system

    NASA Astrophysics Data System (ADS)

    Kaplan, S. I.

    1982-01-01

    Physical features and startup characteristics of a 240 kW parabolic trough photovoltaic power system are described. The Mississippi County Community College array (Blytheville, AR) comprises 45 rows of linear parabolic troughs oriented N-S, which track E-W by means of a hydraulically driven actuator. The solar input is focussed onto 50/50 water-glycol cooled receiver bars on which Si solar cells are mounted. Nominal operating temperature for the cells is 50 C, with the heat transferred to the building heat supply in the winter. The output is routed through a power conditioning unit for inversion to 480 V ac power, for use by the school or, when the demand is exceeded, for direct transmission into the utility grid. Problems during startup have included misalignment, due to gravitational torquing and twisting, standoff insulation, and tracking during cloudy periods. Output has been 45% of design during the autumn of 1981.

  5. Predicting the Spectral Effects of Soils on Concentrating Photovoltaic Systems

    DOE PAGES

    Burton, Patrick D.; King, Bruce Hardison; Riley, Daniel M.

    2014-12-15

    The soiling losses on high concentrating photovoltaic (HCPV) systems may be influenced by the spectral properties of accumulated soil. We predicted the response of an isotype cell to changes in spectral content and reduction in transmission due to soiling using measured UV/vis transmittance through soil films. Artificial soil test blends deposited on glass coupons were used to supply the transmission data, which was then used to calculate the effect on model spectra. Moreover, the wavelength transparency of the test soil was varied by incorporating red and yellow mineral pigments into graded sand. The more spectrally responsive (yellow) soils were predictedmore » to alter the current balance between the top and middle subcells throughout a range of air masses corresponding to daily and seasonal variation.« less

  6. Predicting the Spectral Effects of Soils on Concentrating Photovoltaic Systems

    SciTech Connect

    Burton, Patrick D.; King, Bruce Hardison; Riley, Daniel M.

    2014-12-15

    The soiling losses on high concentrating photovoltaic (HCPV) systems may be influenced by the spectral properties of accumulated soil. We predicted the response of an isotype cell to changes in spectral content and reduction in transmission due to soiling using measured UV/vis transmittance through soil films. Artificial soil test blends deposited on glass coupons were used to supply the transmission data, which was then used to calculate the effect on model spectra. Moreover, the wavelength transparency of the test soil was varied by incorporating red and yellow mineral pigments into graded sand. The more spectrally responsive (yellow) soils were predicted to alter the current balance between the top and middle subcells throughout a range of air masses corresponding to daily and seasonal variation.

  7. System for characterizing semiconductor materials and photovoltaic devices through calibration

    DOEpatents

    Sopori, Bhushan L.; Allen, Larry C.; Marshall, Craig; Murphy, Robert C.; Marshall, Todd

    1998-01-01

    A method and apparatus for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby.

  8. System for characterizing semiconductor materials and photovoltaic devices through calibration

    DOEpatents

    Sopori, B.L.; Allen, L.C.; Marshall, C.; Murphy, R.C.; Marshall, T.

    1998-05-26

    A method and apparatus are disclosed for measuring characteristics of a piece of material, typically semiconductor materials including photovoltaic devices. The characteristics may include dislocation defect density, grain boundaries, reflectance, external LBIC, internal LBIC, and minority carrier diffusion length. The apparatus includes a light source, an integrating sphere, and a detector communicating with a computer. The measurement or calculation of the characteristics is calibrated to provide accurate, absolute values. The calibration is performed by substituting a standard sample for the piece of material, the sample having a known quantity of one or more of the relevant characteristics. The quantity measured by the system of the relevant characteristic is compared to the known quantity and a calibration constant is created thereby. 44 figs.

  9. Advanced worker protection system

    SciTech Connect

    Caldwell, B.; Duncan, P.; Myers, J.

    1995-10-01

    The Department of Energy (DOE) is in the process of defining the magnitude and diversity of Decontamination and Decommissioning (D&D) obligations at its numerous sites. The DOE believes that existing technologies are inadequate to solve many challenging problems such as how to decontaminate structures and equipment cost effectively, what to do with materials and wastes generated, and how to adequately protect workers and the environment. Preliminary estimates show a tremendous need for effective use of resources over a relatively long period (over 30 years). Several technologies are being investigated which can potentially reduce D&D costs while providing appropriate protection to DOE workers. The DOE recognizes that traditional methods used by the EPA in hazardous waste site clean up activities are insufficient to provide the needed protection and worker productivity demanded by DOE D&D programs. As a consequence, new clothing and equipment which can adequately protect workers while providing increases in worker productivity are being sought for implementation at DOE sites. This project describes the development of an Advanced Worker Protection System (AWPS) which will include a life-support backpack with liquid air for cooling and as a supply of breathing gas, protective clothing, respirators, communications, and support equipment.

  10. Comparative Study Between Wind and Photovoltaic (PV) Systems

    NASA Astrophysics Data System (ADS)

    Taha, Wesam

    This paper reviews two renewable energy systems; wind and photovoltaic (PV) systems. The common debate between the two of them is to conclude which one is better, in terms of cost and efficiency. Therefore, comparative study, in terms of cost and efficiency, is attempted. Regarding total cost of both, wind and PV systems, many parameters must be taken into consideration such as availability of energy (either wind or solar), operation and maintenance, availability of costumers, political influence, and the components used in building the system. The main components and parameters that play major role in determining the overall efficiency of wind systems are the wind turbine generator (WTG), gearbox and control technologies such as power, and speed control. On the other hand, in grid-connected PV systems (GCPVS), converter architecture along with maximum power point tracking (MPPT) algorithm and inverter topologies are the issues that affects the efficiency significantly. Cost and efficiency analyses of both systems have been carried out based on the statistics available till today and would be useful in the progress of renewable energy penetration throughout the world.

  11. Optimum design of a photovoltaic powered pumping system

    NASA Astrophysics Data System (ADS)

    Anis, Wagdy R.; Nour, M. A.

    Photovoltaic (PV)-powered pumping systems are relatively simple and reliable. Hence, they are applied worldwide. Two conventional techniques are currently in use: the first is the 'directly-coupled' system where a PV array is directly coupled to a d.c. motor-pump group; the second is the 'battery-buffered' system where a battery is connected across the array to feed the d.c. motor that drives the pump. Recently, a third system has been proposed, namely, the 'switched-mode' PV-powered pumping system. This system couples the pump to the PV array directly when the storage battery is fully charged. The objective is the maximum utilization of available solar radiation to minimize the cost per pumped cubic meter from a given water depth. For a given location, four main parameters affect the design of this system: (i) d.c. motor-pump group parameters; (ii) PV array size; (iii) battery storage size, and (iv) water storage tank size. It is found that some of the factors are more effective in reducing the cost than others. The PV array size is the predominant factor, while the battery storage and water-tank sizes have relatively less effect. A detailed economic analysis is given.

  12. ADVANCED WORKER PROTECTION SYSTEM

    SciTech Connect

    Judson Hedgehock

    2001-03-16

    From 1993 to 2000, OSS worked under a cost share contract from the Department of Energy (DOE) to develop an Advanced Worker Protection System (AWPS). The AWPS is a protective ensemble that provides the user with both breathing air and cooling for a NIOSH-rated duration of two hours. The ensemble consists of a liquid air based backpack, a Liquid Cooling Garment (LCG), and an outer protective garment. The AWPS project was divided into two phases. During Phase 1, OSS developed and tested a full-scale prototype AWPS. The testing showed that workers using the AWPS could work twice as long as workers using a standard SCBA. The testing also provided performance data on the AWPS in different environments that was used during Phase 2 to optimize the design. During Phase 1, OSS also performed a life-cycle cost analysis on a representative clean up effort. The analysis indicated that the AWPS could save the DOE millions of dollars on D and D activities and improve the health and safety of their workers. During Phase 2, OSS worked to optimize the AWPS design to increase system reliability, to improve system performance and comfort, and to reduce the backpack weight and manufacturing costs. To support this design effort, OSS developed and tested several different generations of prototype units. Two separate successful evaluations of the ensemble were performed by the International Union of Operation Engineers (IUOE). The results of these evaluations were used to drive the design. During Phase 2, OSS also pursued certifying the AWPS with the applicable government agencies. The initial intent during Phase 2 was to finalize the design and then to certify the system. OSS and Scott Health and Safety Products teamed to optimize the AWPS design and then certify the system with the National Institute of Occupational Health and Safety (NIOSH). Unfortunately, technical and programmatic difficulties prevented us from obtaining NIOSH certification. Despite the inability of NIOSH to certify

  13. Diffusion of Innovation: Factors Promoting Interest in Solar Photovoltaic Generation Systems Within Air Force Installations

    DTIC Science & Technology

    2007-03-01

    Q42c. How likely is it that your base will request funding in these systems in the next 10 years? (large scale) Q43a.How beneficial do you think it...DIFFUSION OF INNOVATION: FACTORS PROMOTING INTEREST IN SOLAR PHOTOVOLTAIC GENERATION SYSTEMS WITHIN AIR...SOLAR PHOTOVOLTAIC GENERATION SYSTEMS WITHIN AIR FORCE INSTALLATIONS THESIS Presented to the Faculty Department of Systems and Engineering

  14. Photovoltaic power system for satellite Earth stations in remote areas: Project status and design description

    NASA Technical Reports Server (NTRS)

    Delombard, R.

    1984-01-01

    A photovoltaic power system which will be installed at a remote location in Indonesia to provide power for a satellite Earth station and a classroom for video and audio teleconferences are described. The Earth station may also provide telephone service to a nearby village. The use of satellite communications for development assistance applications and the suitability of a hybrid photovoltaic engine generator power system for remote satellite Earth stations are demonstrated. The Indonesian rural satellite project is discussed and the photovoltaic power system is described.

  15. Analysis of the economics of photovoltaic-diesel-battery energy systems for remote applications

    NASA Technical Reports Server (NTRS)

    Brainard, W. A.

    1983-01-01

    Computer simulations were conducted to analyze the performance and operating cost of a photovoltaic energy source combined with a diesel generator system and battery storage. The simulations were based on the load demand profiles used for the design of an all photovoltaic energy system installed in the remote Papago Indian Village of Schuchuli, Arizona. Twenty year simulations were run using solar insolation data from Phoenix SOLMET tapes. Total energy produced, energy consumed, operation and maintenance costs were calculated. The life cycle and levelized energy costs were determined for a variety of system configurations (i.e., varying amounts of photovoltaic array and battery storage).

  16. Renewable Energy, Photovoltaic Systems Near Airfields. Electromagnetic Interference

    SciTech Connect

    Deline, Chris; Dann, Geoff

    2015-04-01

    Recent increases in photovoltaic (PV) systems on Department of the Navy (DON) land and potential siting near airfields prompted Commander, Naval Installations Command to fund the Naval Facilities Engineering Command to evaluate the impact of electromagnetic interference (EMI) from PV systems on airfield electronic equipment. Naval Facilities Engineering and Expeditionary Warfare Center tasked Department of Energy National Renewable Energy laboratory (NREL) to conduct the assessment. PV systems often include high-speed switching semiconductor circuits to convert the voltage produced by the PV arrays to the voltage needed by the end user. Switching circuits inherently produce electromagnetic radiation at harmonics of the switching frequency. In this report, existing literature is summarized and tests to measure emissions and mitigation methods are discussed. The literature shows that the emissions from typical PV systems are low strength and unlikely to cause interference to most airfield electronic systems. With diligent procurement and siting of PV systems, including specifications for FCC Part 15 Class A compliant equipment and a 250-foot setback from communication equipment, NREL anticipates little to no EMI impact on nearby communications or telemetry equipment.

  17. Improving the efficiency of solar photovoltaic power system

    NASA Astrophysics Data System (ADS)

    Aribisala, Henry A.

    As the local and national clamor for foreign energy independent United States continues to grow unabated; renewable energy has been receiving increased focus and it's widely believed that it's not only the answer to ever increasing demand for energy in this country, but also the environmentally friendly means of meeting such demand. During the spring of 2010, I was involved with a 5KW solar power system design project; the project involved designing and building solar panels and associated accessories like the solar array mounts and Solar Inverter system. One of the key issues we ran into during the initial stage of the project was how to select efficient solar cells for panel building at a reasonable cost. While we were able to purchase good solar cells within our allocated budget, the issue of design for efficiency was not fully understood , not just in the contest of solar cells performance , but also in the overall system efficiency of the whole solar power system, hence the door was opened for this thesis. My thesis explored and expanded beyond the scope of the aforementioned project to research different avenues for improving the efficiency of solar photo-voltaic power system from the solar cell level to the solar array mounting, array tracking and DC-AC inversion system techniques.

  18. Advanced Integrated Traction System

    SciTech Connect

    Greg Smith; Charles Gough

    2011-08-31

    The United States Department of Energy elaborates the compelling need for a commercialized competitively priced electric traction drive system to proliferate the acceptance of HEVs, PHEVs, and FCVs in the market. The desired end result is a technically and commercially verified integrated ETS (Electric Traction System) product design that can be manufactured and distributed through a broad network of competitive suppliers to all auto manufacturers. The objectives of this FCVT program are to develop advanced technologies for an integrated ETS capable of 55kW peak power for 18 seconds and 30kW of continuous power. Additionally, to accommodate a variety of automotive platforms the ETS design should be scalable to 120kW peak power for 18 seconds and 65kW of continuous power. The ETS (exclusive of the DC/DC Converter) is to cost no more than $660 (55kW at $12/kW) to produce in quantities of 100,000 units per year, should have a total weight less than 46kg, and have a volume less than 16 liters. The cost target for the optional Bi-Directional DC/DC Converter is $375. The goal is to achieve these targets with the use of engine coolant at a nominal temperature of 105C. The system efficiency should exceed 90% at 20% of rated torque over 10% to 100% of maximum speed. The nominal operating system voltage is to be 325V, with consideration for higher voltages. This project investigated a wide range of technologies, including ETS topologies, components, and interconnects. Each technology and its validity for automotive use were verified and then these technologies were integrated into a high temperature ETS design that would support a wide variety of applications (fuel cell, hybrids, electrics, and plug-ins). This ETS met all the DOE 2010 objectives of cost, weight, volume and efficiency, and the specific power and power density 2015 objectives. Additionally a bi-directional converter was developed that provides charging and electric power take-off which is the first step

  19. ADVANCED TURBINE SYSTEMS PROGRAM

    SciTech Connect

    Sy Ali

    2002-03-01

    The market for power generation equipment is undergoing a tremendous transformation. The traditional electric utility industry is restructuring, promising new opportunities and challenges for all facilities to meet their demands for electric and thermal energy. Now more than ever, facilities have a host of options to choose from, including new distributed generation (DG) technologies that are entering the market as well as existing DG options that are improving in cost and performance. The market is beginning to recognize that some of these users have needs beyond traditional grid-based power. Together, these changes are motivating commercial and industrial facilities to re-evaluate their current mix of energy services. One of the emerging generating options is a new breed of advanced fuel cells. While there are a variety of fuel cell technologies being developed, the solid oxide fuel cells (SOFC) and molten carbonate fuel cells (MCFC) are especially promising, with their electric efficiency expected around 50-60 percent and their ability to generate either hot water or high quality steam. In addition, they both have the attractive characteristics of all fuel cells--relatively small siting footprint, rapid response to changing loads, very low emissions, quiet operation, and an inherently modular design lending itself to capacity expansion at predictable unit cost with reasonably short lead times. The objectives of this project are to:(1) Estimate the market potential for high efficiency fuel cell hybrids in the U.S.;(2) Segment market size by commercial, industrial, and other key markets;(3) Identify and evaluate potential early adopters; and(4) Develop results that will help prioritize and target future R&D investments. The study focuses on high efficiency MCFC- and SOFC-based hybrids and competing systems such as gas turbines, reciprocating engines, fuel cells and traditional grid service. Specific regions in the country have been identified where these

  20. Advanced Microturbine Systems

    SciTech Connect

    Rosfjord, T; Tredway, W; Chen, A; Mulugeta, J; Bhatia, T

    2008-12-31

    In July 2000, the United Technologies Research Center (UTRC) was one of five recipients of a US Department of Energy contract under the Advanced Microturbine System (AMS) program managed by the Office of Distributed Energy (DE). The AMS program resulted from several government-industry workshops that recognized that microturbine systems could play an important role in improving customer choice and value for electrical power. That is, the group believed that electrical power could be delivered to customers more efficiently and reliably than the grid if an effective distributed energy strategy was followed. Further, the production of this distributed power would be accomplished with less undesirable pollutants of nitric oxides (NOx) unburned hydrocarbons (UHC), and carbon monoxide (CO). In 2000, the electrical grid delivered energy to US customers at a national average of approximately 32% efficiency. This value reflects a wide range of powerplants, but is dominated by older, coal burning stations that provide approximately 50% of US electrical power. The grid efficiency is also affected by transmission and distribution (T&D) line losses that can be significant during peak power usage. In some locations this loss is estimated to be 15%. Load pockets can also be so constrained that sufficient power cannot be transmitted without requiring the installation of new wires. New T&D can be very expensive and challenging as it is often required in populated regions that do not want above ground wires. While historically grid reliability has satisfied most customers, increasing electronic transactions and the computer-controlled processes of the 'digital economy' demand higher reliability. For them, power outages can be very costly because of transaction, work-in-progress, or perishable commodity losses. Powerplants that produce the grid electrical power emit significant levels of undesirable NOx, UHC, and CO pollutants. The level of emission is quoted as either a technology

  1. Building integration of photovoltaic systems in cold climates

    NASA Astrophysics Data System (ADS)

    Athienitis, Andreas K.; Candanedo, José A.

    2010-06-01

    This paper presents some of the research activities on building-integrated photovoltaic (BIPV) systems developed by the Solar and Daylighting Laboratory at Concordia University. BIPV systems offer considerable advantages as compared to stand-alone PV installations. For example, BIPV systems can play a role as essential components of the building envelope. BIPV systems operate as distributed power generators using the most widely available renewable source. Since BIPV systems do not require additional space, they are especially appropriate for urban environments. BIPV/Thermal (BIPV/T) systems may use exterior air to extract useful heat from the PV panels, cooling them and thereby improving their electric performance. The recovered thermal energy can then be used for space heating and domestic hot water (DHW) heating, supporting the utilization of BIVP/T as an appropriate technology for cold climates. BIPV and BIPV/T systems are the subject of several ongoing research and demonstration projects (in both residential and commercial buildings) led by Concordia University. The concept of integrated building design and operation is at the centre of these efforts: BIPV and BIPV/T systems must be treated as part of a comprehensive strategy taking into account energy conservation measures, passive solar design, efficient lighting and HVAC systems, and integration of other renewable energy systems (solar thermal, heat pumps, etc.). Concordia Solar Laboratory performs fundamental research on heat transfer and modeling of BIPV/T systems, numerical and experimental investigations on BIPV and BIPV/T in building energy systems and non-conventional applications (building-attached greenhouses), and the design and optimization of buildings and communities.

  2. Recent Advances in Organic Photovoltaics: Device Structure and Optical Engineering Optimization on the Nanoscale.

    PubMed

    Luo, Guoping; Ren, Xingang; Zhang, Su; Wu, Hongbin; Choy, Wallace C H; He, Zhicai; Cao, Yong

    2016-03-23

    Organic photovoltaic (OPV) devices, which can directly convert absorbed sunlight to electricity, are stacked thin films of tens to hundreds of nanometers. They have emerged as a promising candidate for affordable, clean, and renewable energy. In the past few years, a rapid increase has been seen in the power conversion efficiency of OPV devices toward 10% and above, through comprehensive optimizations via novel photoactive donor and acceptor materials, control of thin-film morphology on the nanoscale, device structure developments, and interfacial and optical engineering. The intrinsic problems of short exciton diffusion length and low carrier mobility in organic semiconductors creates a challenge for OPV designs for achieving optically thick and electrically thin device structures to achieve sufficient light absorption and efficient electron/hole extraction. Recent advances in the field of OPV devices are reviewed, with a focus on the progress in device architecture and optical engineering approaches that lead to improved electrical and optical characteristics in OPV devices. Successful strategies are highlighted for light wave distribution, modulation, and absorption promotion inside the active layer of OPV devices by incorporating periodic nanopatterns/nanostructures or incorporating metallic nanomaterials and nanostructures.

  3. Photovoltaic-powered regulated cathodic-protection system

    NASA Astrophysics Data System (ADS)

    Anis, Wagdy R.; Alfons, Hany A.

    The objective of a cathodic protection system is to protect metallic structures against corrosion. To achieve this, a sacrificial anode is connected to the protected structure (which acts as a cathode) through a d.c. power supply. To stop the corrosion, the protected structure requires a constant current. The current is determined by the metal and area of the structure, as well as the surrounding medium. The major difficulty in achieving a constant current is the variation in the resistivity of the surrounding medium that is caused by changes in the climatic conditions. Conventional cathodic-protection systems resolve this problem by manual adjustment of the d.c. voltage periodically to obtain a constant current. Such adjustment depends on the experience of the technician and the accuracy of the measuring equipment. Moreover if the interval between successive adjustments is relative long, the corrosion could become excessive. To overcome such difficulties, an automatically regulated system has been developed. The proposed system senses variations is the resistivity of the surrounding medium and adjusts the d.c. voltage accordingly so that the current is kept constant at the required level. The design of a solar photovoltaic system to supply the required d.c. power is discussed in this communication.

  4. The photovoltaic solar system - Analysis and basic design rules

    NASA Astrophysics Data System (ADS)

    Kipperman, A. H. M.

    Photovoltaic array designs developed for two European sites are presented, with consideration given to cost optimization of the sytems with respect to the array output and the storage requirements. The control system programming is conditioned by the statistically determined insolation at a site and the necessity of supplying uninterrupted power to the load. The sizing of the battery storage system depends on costs considered for other back-up power generation and the value of the product of the power usage, with the additional consideration of the natural diurnal cycle of power generation. The two systems considered produce 1 kWh/day, with 20 pct needed in the daytime, a battery system with a 60 pct depth of discharge, 70 pct efficiency, and a four year life at $200/kWh. It is shown that no clear-cut optimum design is possible for one system, although an array design can be chosen with the minimum possible cost to achieve the required output.

  5. Dynamic thermal analysis of a concentrated photovoltaic system

    NASA Astrophysics Data System (ADS)

    Avrett, John T., II; Cain, Stephen C.; Pochet, Michael

    2012-02-01

    Concentrated photovoltaic (PV) technology represents a growing market in the field of terrestrial solar energy production. As the demand for renewable energy technologies increases, further importance is placed upon the modeling, design, and simulation of these systems. Given the U.S. Air Force cultural shift towards energy awareness and conservation, several concentrated PV systems have been installed on Air Force installations across the country. However, there has been a dearth of research within the Air Force devoted to understanding these systems in order to possibly improve the existing technologies. This research presents a new model for a simple concentrated PV system. This model accurately determines the steady state operating temperature as a function of the concentration factor for the optical part of the concentrated PV system, in order to calculate the optimum concentration that maximizes power output and efficiency. The dynamic thermal model derived is validated experimentally using a commercial polysilicon solar cell, and is shown to accurately predict the steady state temperature and ideal concentration factor.

  6. Control aspects of the Schuchuli Village stand-alone photovoltaic power system

    NASA Technical Reports Server (NTRS)

    Groumpos, P. P.; Culler, J. E.; Delombard, R.

    1984-01-01

    A photovoltaic power system in an Arizona Indian village was installed. The control subsystem of this photovoltaic power system was analyzed. The four major functions of the control subsystem are: (1) voltage regulation; (2) load management; (3) water pump control; and (4) system protection. The control subsystem functions flowcharts for the control subsystem operation, and a computer program that models the control subsystem are presented.

  7. Market assessment of photovoltaic power systems for agricultural applications in Nigeria

    NASA Technical Reports Server (NTRS)

    Staples, D.; Steingass, H.; Nolfi, J.

    1981-01-01

    The market potential for stand-alone photovoltaic systems in agriculture was studied. Information is presented on technical and economically feasible applications, and assessments of the business, government and financial climate for photovoltaic sales. It is concluded that the market for stand-alone systems will be large because of the availability of captial and the high premium placed on high reliability, low maintenance power systems. Various specific applications are described, mostly related to agriculture.

  8. Design and fabrication of a prototype system for photovoltaic residences in the Southwest

    NASA Astrophysics Data System (ADS)

    1982-06-01

    Described are the design of a photovoltaic powered residence for the American Southwest, dubbed Casa fotovoltaica, and the construction of a prototype building at the Southwest Residential Experiment Station for testing the performance of the full size photovoltaic (PV) system. Included are architectural drawings of both the residence and the prototype, analysis of the energy requirements of the residence, prediction of PV system output, description of the electrical system, and history of the construction process of the prototype.

  9. Analysis of merits of hybrid wind/photovoltaic concept for stand-alone systems

    NASA Astrophysics Data System (ADS)

    Castle, J. A.; Kallis, J. M.; Moite, S. M.; Marshall, N. A.

    Methods for evaluating the merits of hybrid wind/photovoltaic systems for use in stand-alone applications were developed. The optimum mix of wind and photovoltaic power with an electrochemical storage system, with or without fossil fuel generator backup, depends upon the individual subsystem economics. A computer code was developed to calculate the optimum subsystem sizes that minimize the levelized energy cost. The actual merits of a hybrid system over a pure photovoltaic or wind system depend upon many factors: load profile; wind regime; insolation; cost and availability of backup power; the relative costs of wind rotor area, array area, and storage; and subsystem efficiency factors. Examples of optimized hybrid systems for a range of photovoltaic costs and estimated wind and storage costs are shown for an Ely, NV, application, where backup power is allowed to supply 5% of the total annual load.

  10. Advanced program weight control system

    NASA Technical Reports Server (NTRS)

    Derwa, G. T.

    1978-01-01

    The design and implementation of the Advanced Program Weight Control System (APWCS) are reported. The APWCS system allows the coordination of vehicle weight reduction programs well in advance so as to meet mandated requirements of fuel economy imposed by government and to achieve corporate targets of vehicle weights. The system is being used by multiple engineering offices to track weight reduction from inception to eventual production. The projected annualized savings due to the APWCS system is over $2.5 million.

  11. Enhanced power quality based single phase photovoltaic distributed generation system

    NASA Astrophysics Data System (ADS)

    Panda, Aurobinda; Pathak, M. K.; Srivastava, S. P.

    2016-08-01

    This article presents a novel control strategy for a 1-ϕ 2-level grid-tie photovoltaic (PV) inverter to enhance the power quality (PQ) of a PV distributed generation (PVDG) system. The objective is to obtain the maximum benefits from the grid-tie PV inverter by introducing current harmonics as well as reactive power compensation schemes in its control strategy, thereby controlling the PV inverter to achieve multiple functions in the PVDG system such as: (1) active power flow control between the PV inverter and the grid, (2) reactive power compensation, and (3) grid current harmonics compensation. A PQ enhancement controller (PQEC) has been designed to achieve the aforementioned objectives. The issue of underutilisation of the PV inverter in nighttime has also been addressed in this article and for the optimal use of the system; the PV inverter is used as a shunt active power filter in nighttime. A prototype model of the proposed system is developed in the laboratory, to validate the effectiveness of the control scheme, and is tested with the help of the dSPACE DS1104 platform.

  12. Photovoltaic Powering And Control System For Electrochromic Windows

    DOEpatents

    Schulz, Stephen C.; Michalski, Lech A.; Volltrauer, Hermann N.; Van Dine, John E.

    2000-04-25

    A sealed insulated glass unit is provided with an electrochromic device for modulating light passing through the unit. The electrochromic device is controlled from outside the unit by a remote control electrically unconnected to the device. Circuitry within the unit may be magnetically controlled from outside. The electrochromic device is powered by a photovoltaic cells. The photovoltaic cells may be positioned so that at least a part of the light incident on the cell passes through the electrochromic device, providing a form of feedback control. A variable resistance placed in parallel with the electrochromic element is used to control the response of the electrochromic element to changes in output of the photovoltaic cell.

  13. PVUSA instrumentation and data analysis techniques for photovoltaic systems

    SciTech Connect

    Newmiller, J.; Hutchinson, P.; Townsend, T.; Whitaker, C.

    1995-10-01

    The Photovoltaics for Utility Scale Applications (PVUSA) project tests two types of PV systems at the main test site in Davis, California: new module technologies fielded as 20-kW Emerging Module Technology (EMT) arrays and more mature technologies fielded as 70- to 500-kW turnkey Utility-Scale (US) systems. PVUSA members have also installed systems in their service areas. Designed appropriately, data acquisition systems (DASs) can be a convenient and reliable means of assessing system performance, value, and health. Improperly designed, they can be complicated, difficult to use and maintain, and provide data of questionable validity. This report documents PVUSA PV system instrumentation and data analysis techniques and lessons learned. The report is intended to assist utility engineers, PV system designers, and project managers in establishing an objective, then, through a logical series of topics, facilitate selection and design of a DAS to meet the objective. Report sections include Performance Reporting Objectives (including operational versus research DAS), Recommended Measurements, Measurement Techniques, Calibration Issues, and Data Processing and Analysis Techniques. Conclusions and recommendations based on the several years of operation and performance monitoring are offered. This report is one in a series of 1994--1995 PVUSA reports documenting PVUSA lessons learned at the demonstration sites in Davis and Kerman, California. Other topical reports address: five-year assessment of EMTs; validation of the Kerman 500-kW grid support PV plant benefits; construction and safety experience in installing and operating PV systems; balance-of-system design and costs; procurement, acceptance, and rating practices for PV power plants; experience with power conditioning units and power quality.

  14. Synergic system between photovoltaic module and microbial fuel cell with simultaneous pollution control

    NASA Astrophysics Data System (ADS)

    Vasyliv, Oresta; Dhere, Neelkanth G.

    2015-05-01

    Combined photovoltaic module-microbial fuel cell construction shows prospect of advanced autonomous functioning effective energy-production system with the possibility of round-the-clock power generation. Application of Desulfuromonas sp. as anode biocatalyst in photovoltaic (PV) - microbial fuel cell (MFC) could support highly effective eco-friendly energy derivation with simultaneous reduction of organic and inorganic wastes in water environment. D. acetoxidans is exoelectrogenic bacterium that supports S0-reduction with H2S formation and S0-oxidation while an electrode serves as the electron acceptor. Simultaneous sulfur redox processes enhance electron transfer to the electrode surface that may increase the effectiveness of microbial fuel cell performance. It was shown that D. acetoxidans IMV B-7384 possesses selective resistance to 0.5-2.5 mM of copper, iron, nickel, manganese and lead ions. Metal-resistant strains of this bacterium may help overcome H2S toxicity, which is produced because of dissimilative S0-reduction, since divalent cations will interact with sulfide ions, forming insoluble precipitates. Thus D. acetoxidans IMV B-7384 may be applied for remediation of toxic metal ions from water environments because of metal fixation in form of insoluble complexes of metal sulfides. D. acetoxidans IMV B-7384 is presumed to have the capability to convert organic compounds, such as malate, pyruvate, succinate and fumarate via reductive stage of tricarboxylic acid cycle. Thus application of effluents as anolyte in MFC, based on D. acetoxidans IMV B-7384, may cause decrease of its organic content with formation of simple benign constituents, such as CO2 and H2O. Hence the advanced system for eco-friendly energy generation with simultaneous water pollution control is proposed.

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

    SciTech Connect

    Kern, E.C. Jr.

    1986-06-01

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

  16. Photovoltaic system costs using local labor and materials in developing countries

    NASA Technical Reports Server (NTRS)

    Jacobson, E.; Fletcher, G.; Hein, G.

    1980-01-01

    The use of photovoltaic (PV) technology in countries that do not presently have high technology industrial capacity was investigated. The relative cost of integrating indigenous labor (and manufacturing where available) into the balance of the system industry of seven countries (Egypt, Haiti, the Ivory Coast, Kenya, Mexico, Nepal, and the Phillipines) was determined. The results were then generalized to other countries, at most levels of development. The results of the study imply several conclusions: (1) the cost of installing and maintaining comparable photovoltaic systems in developing countries is less than in the United States; (2) skills and some materials are available in the seven subject countries that may be applied to constructing and maintaining PV systems; (3) there is an interest in foreign countries in photovoltaics; and (4) conversations with foreign nationals suggest that photovoltaics must be introduced in foreign markets as an appropriate technology with high technology components rather than as a high technology system.

  17. SIMWEST: A simulation model for wind and photovoltaic energy storage systems (CDC user's manual), volume 1

    NASA Technical Reports Server (NTRS)

    Warren, A. W.; Esinger, A. W.

    1979-01-01

    Procedures are given for using the SIMWEST program on CDC 6000 series computers. This expanded software package includes wind and/or photovoltaic systems utilizing any combination of five types of storage (pumped hydro, battery, thermal, flywheel, and pneumatic).

  18. PVUSA model technical specification for a turnkey photovoltaic power system

    SciTech Connect

    Dows, R.N.; Gough, E.J.

    1995-11-01

    One of the five objectives of PVUSA is to offer U.S. utilities hands-on experience in designing, procuring, and operating PV systems. The procurement process included the development of a detailed set of technical requirements for a PV system. PVUSA embodied its requirements in a technical specification used as an attachment to its contracts for four utility-scale PV systems in the 200 kW to 500 kW range. The technical specification has also been adapted and used by several utilities. The PVUSA Technical Specification has now been updated and is presented here as a Model Technical Specification (MTS) for utility use. The MTS text is also furnished on a computer disk in Microsoft Word 6.0 so that it may be conveniently adapted by each user. The text includes guidance in the form of comments and by the use of parentheses to indicate where technical information must be developed and inserted. Commercial terms and conditions will reflect the procurement practice of the buyer. The reader is referred to PG&E Report Number 95-3090000. 1, PVUSA Procurement, Acceptance and Rating Practices for Photovoltaic Power Plants (1995) for PVUSA experience and practice. The MTS is regarded by PVUSA as a use-proven document, but needs to be adapted with care and attention to detail.

  19. Energy Payback Time of a Rooftop Photovoltaic System in Greece

    NASA Astrophysics Data System (ADS)

    Rachoutis, E.; Koubogiannis, D.

    2016-11-01

    Life Cycle Analysis (LCA) is an important tool to quantitatively assess energy consumption and environmental impact of any product. Current research related to energy consumption in buildings moves towards Nearly Zero Energy Building (NZEB). In such a building, an important issue concerns the energy production by renewable sources, including on-site production. The most feasible way to achieve renewable energy utilization in a building level in Greece is by using rooftop Photovoltaic (PV) systems, also promoted in the last decade by the national legislation concerning energy conservation measures. Apart from cost-related issues and payback times, Embodied Energy (EE) and Embodied CO2 (ECO2) emissions have also to be considered against the anticipated corresponding savings. Using a particular PV system as a case study, its basic constitutive materials are determined and their masses are calculated. Embodied energy values are estimated by using embodied energy coefficients available in the international literature. Considering a specific geographic location in Greece for the building on which the PV is installed, the annual energy generated by the system is estimated based on its performance data and curves. The Energy and CO2 Payback Times (EPBT and CO2PBT) are estimated and assessed, as well as future work is suggested.

  20. Photovoltaic energy systems: Program summary fiscal year 1983

    NASA Technical Reports Server (NTRS)

    1984-01-01

    An overview of government funded activities in photovoltaic energy conversion research is given. Introductory information, a list of directing organizations, a list of acronyms and abbreviations, and an index of current contractors are given.

  1. Photovoltaic array with minimally penetrating rooftop support system

    DOEpatents

    Lenox, Carl J.S.

    2012-10-23

    A photovoltaic array including a plurality of photovoltaic assemblies and a plurality of mounting units. The mounting units each include an elongate rail and a plurality of leg assemblies. The rail is sized and configured to maintain a portion of at least two of the photovoltaic assemblies, with the leg assemblies extending from the rail in a spaced-apart fashion and terminating in a foot for placement against a rooftop structure for minimally penetration installation. Further, at least one of the leg assemblies can include a retractable leg. When the photovoltaic array is installed to a rooftop structure including a membrane intermittently secured to a rooftop deck, the retractable leg accommodates upward billowing of the membrane under windy conditions.

  2. Demonstration of Photovoltaic-Powered Cathodic Protection System with Remote Monitoring Capability

    DTIC Science & Technology

    2014-02-01

    ER D C/ CE RL T R- 14 -3 DoD Corrosion Prevention and Control Program Demonstration of Photovoltaic-Powered Cathodic Protection System... Prevention and Control Program ERDC/CERL TR-14-3 February 2014 Demonstration of Photovoltaic-Powered Cathodic Protection System with Remote...demonstration was performed for the Office of the Secretary of De- fense (OSD) under Department of Defense (DoD) Corrosion Control and Prevention Project

  3. Uncertainty and sensitivity analysis for photovoltaic system modeling.

    SciTech Connect

    Hansen, Clifford W.; Pohl, Andrew Phillip; Jordan, Dirk

    2013-12-01

    We report an uncertainty and sensitivity analysis for modeling DC energy from photovoltaic systems. We consider two systems, each comprised of a single module using either crystalline silicon or CdTe cells, and located either at Albuquerque, NM, or Golden, CO. Output from a PV system is predicted by a sequence of models. Uncertainty in the output of each model is quantified by empirical distributions of each model's residuals. We sample these distributions to propagate uncertainty through the sequence of models to obtain an empirical distribution for each PV system's output. We considered models that: (1) translate measured global horizontal, direct and global diffuse irradiance to plane-of-array irradiance; (2) estimate effective irradiance from plane-of-array irradiance; (3) predict cell temperature; and (4) estimate DC voltage, current and power. We found that the uncertainty in PV system output to be relatively small, on the order of 1% for daily energy. Four alternative models were considered for the POA irradiance modeling step; we did not find the choice of one of these models to be of great significance. However, we observed that the POA irradiance model introduced a bias of upwards of 5% of daily energy which translates directly to a systematic difference in predicted energy. Sensitivity analyses relate uncertainty in the PV system output to uncertainty arising from each model. We found that the residuals arising from the POA irradiance and the effective irradiance models to be the dominant contributors to residuals for daily energy, for either technology or location considered. This analysis indicates that efforts to reduce the uncertainty in PV system output should focus on improvements to the POA and effective irradiance models.

  4. Fundamental and applied studies of organic photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Hill, Caleb M.

    Presented here are applied and fundamental studies of model organic photovoltaic (OPV) systems. Graphene oxide (GO) nanosheets were investigated as a potential electron acceptor in bulk heterojunction organic solar cells which employed poly[3-hexylthiophene] (P3HT) as an electron donor. GO nanosheets were transferred into organic solution through a surfactant-assisted phase transfer method. Electron transfer from P3HT to GO in solutions and thin films was established through fluorescence spectroscopy. Bulk heterojunction solar cells containing P3HT, P3HT-GO, and P3HT-phenyl-C61-butyric acid methyl ester (PCBM, a prototypical elector acceptor employed in polymer solar cells) were constructed and evaluated. Single molecule fluorescence spectroscopy was employed to study charge transfer between conjugated polymers and TiO2 at the single molecule level. The fluorescence of individual chains of the conjugated polymer poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) at TiO2 surfaces was shown to exhibit increased intermittent (on/off "blinking") behavior compared to molecules on glass substrates. Single molecule fluorescence excitation anisotropy measurements showed the conformation of the polymer molecules did not differ appreciably between glass and TiO 2 substrates. The similarities in molecular conformation suggest that the observed differences in blinking activity are due to charge transfer between MEH-PPV and TiO2, which provides additional pathways between states of high and low fluorescence quantum efficiency. The electrodeposition of individual Ag nanoparticles (NPs), which can be used to enhance light harvesting in organic photovoltaic systems, was studied in situ via dark field scattering (DFS) microscopy. The scattering at the surface of an indium tin oxide (ITO) working electrode was measured during a potential sweep. Utilizing Mie scattering theory and high resolution scanning electron microscopy (SEM), the scattering data were used to

  5. Intermediate photovoltaic system application experiment operational performance report. Volume 8: Newman Power Station, El Paso, Texas

    NASA Astrophysics Data System (ADS)

    1982-02-01

    For the month of January, 1982, performance data are given for a photovoltaic power supply used by a Texas electric utility. Data presented include: daily and monthly electrical energy produced; daily and monthly solar energy incident on the array; daily and monthly array efficiency; plots of energy produced as a function of power levels, voltage, cell temperature, and hour of day; electrical energy supplied by the photovoltaic system to the load and the corresponding dollar value; photovoltaic system efficiency; capacity factor; daily photovoltaic power supplied to the load; daily system availability; hourly and monthly insolation; hourly and monthly ambient temperature; hourly and monthly average wind speed; wind direction distribution; number of freeze/thaw cycles; heating and cooling degree days; hourly cell temperature; daily data acquisition mode and recording interval plot. Also included are brief summaries of problems, operations and maintenance events.

  6. Operational experience with intermediate flat-plate photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Risser, V. V.; Zwibel, H. S.

    Operating features, data acquisition, and fault isolation and maintenance procedures at 20 kWp and 100 kWp photovoltaic (PV) installations in Texas and New Mexico are discussed. Weather and system performance are sensed each minute, averages are calculated for each ten readings, and data is stored on magnetic tape. A total of 84 parameters, including 64 string currents, are recorded at the 20 kWp array and 84 parameters, with 42 string currents, are traced in New Mexico. The 20 kW array is coupled to a 197 MW utility power plant, which determines the voltage of the array. It produced 12 MWh in one yr of operation, functioning at 24 pct overall efficiency. The 100 kWp system is coupled to a 60 kW power conditioning unit and feeds a shopping center, producing 8 pct of the annual load with a cap factor of 25 pct and 192 MWh of dc current produced in one year. It was found that under normal conditions washing the panels is not economically justified in terms of the small power lost if washing does not occur. It is concluded that the PV arrays can be successfully used in an automated operation mode.

  7. Photovoltaic balance-of-system designs and costs at PVUSA

    NASA Astrophysics Data System (ADS)

    Reyes, A. B.; Jennings, C.

    1995-05-01

    This report is one in a series of 1994-1995 PVUSA reports that document PVUSA lessons learned at demonstration sites in California and Texas. During the last 7 years (1988 to 1994), 16 PV systems ranging from 20 kW to 500 kW have been installed. Six 20-kW emerging module technology (EMT) arrays and three turnkey (i.e., vendor designed and integrated) utility-scale systems were procured and installed at PVUSA's main test site in Davis, California. PVUSA host utilities have installed a total of seven EMT arrays and utility-scale systems in their service areas. Additional systems at Davis and host utility sites are planned. One of PVUSA's key objectives is to evaluate the performance, reliability, and cost of PV balance-of-system (BOS). In the procurement stage PVUSA encouraged innovative design to improve upon present practice by reducing maintenance, improving reliability, or lowering manufacturing or construction costs. The project team worked closely with suppliers during the design stage not only to ensure designs met functional and safety specifications, but to provide suggestions for improvement. This report, intended for the photovoltaic (PV) industry and for utility project managers and engineers considering PV plant construction and ownership, documents PVUSA utility-scale system design and cost lessons learned. Complementary PVUSA topical reports document: construction and safety experience; five-year assessment of EMTs; validation of the Kerman 500-kW grid-support PV plant benefits; PVUSA instrumentation and data analysis techniques; procurement, acceptance, and rating practices for PV power plants; experience with power conditioning units and power quality.

  8. Photovoltaic balance-of-system designs and costs at PVUSA

    SciTech Connect

    Reyes, A.B.; Jennings, C.

    1995-05-01

    This report is one in a series of 1994-1995 PVUSA reports that document PVUSA lessons learned at demonstration sites in California and Texas. During the last 7 years (1988 to 1994), 16 PV systems ranging from 20 kW to 500 kW have been installed. Six 20-kW emerging module technology (EMT) arrays and three turnkey (i.e., vendor designed and integrated) utility-scale systems were procured and installed at PVUSA`s main test site in Davis, California. PVUSA host utilities have installed a total of seven EMT arrays and utility-scale systems in their service areas. Additional systems at Davis and host utility sites are planned. One of PVUSA`s key objectives is to evaluate the performance, reliability, and cost of PV balance-of-system (BOS). In the procurement stage PVUSA encouraged innovative design to improve upon present practice by reducing maintenance, improving reliability, or lowering manufacturing or construction costs. The project team worked closely with suppliers during the design stage not only to ensure designs met functional and safety specifications, but to provide suggestions for improvement. This report, intended for the photovoltaic (PV) industry and for utility project managers and engineers considering PV plant construction and ownership, documents PVUSA utility-scale system design and cost lessons learned. Complementary PVUSA topical reports document: construction and safety experience; five-year assessment of EMTs; validation of the Kerman 500-kW grid-support PV plant benefits; PVUSA instrumentation and data analysis techniques; procurement, acceptance, and rating practices for PV power plants; experience with power conditioning units and power quality.

  9. Cost of photovoltaic energy systems as determined by balance-of-system costs

    NASA Technical Reports Server (NTRS)

    Rosenblum, L.

    1978-01-01

    The effect of the balance-of-system (BOS), i.e., the total system less the modules, on photo-voltaic energy system costs is discussed for multikilowatt, flat-plate systems. Present BOS costs are in the range of 10 to 16 dollars per peak watt (1978 dollars). BOS costs represent approximately 50% of total system cost. The possibility of future BOS cost reduction is examined. It is concluded that, given the nature of BOS costs and the lack of comprehensive national effort focussed on cost reduction, it is unlikely that BOS costs will decline greatly in the next several years. This prognosis is contrasted with the expectations of the Department of Energy National Photovoltaic Program goals and pending legislation in the Congress which require a BOS cost reduction of an order of magnitude or more by the mid-1980s.

  10. Advanced satellite communication system

    NASA Astrophysics Data System (ADS)

    Staples, Edward J.; Lie, Sen

    1992-05-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  11. Advanced satellite communication system

    NASA Technical Reports Server (NTRS)

    Staples, Edward J.; Lie, Sen

    1992-01-01

    The objective of this research program was to develop an innovative advanced satellite receiver/demodulator utilizing surface acoustic wave (SAW) chirp transform processor and coherent BPSK demodulation. The algorithm of this SAW chirp Fourier transformer is of the Convolve - Multiply - Convolve (CMC) type, utilizing off-the-shelf reflective array compressor (RAC) chirp filters. This satellite receiver, if fully developed, was intended to be used as an on-board multichannel communications repeater. The Advanced Communications Receiver consists of four units: (1) CMC processor, (2) single sideband modulator, (3) demodulator, and (4) chirp waveform generator and individual channel processors. The input signal is composed of multiple user transmission frequencies operating independently from remotely located ground terminals. This signal is Fourier transformed by the CMC Processor into a unique time slot for each user frequency. The CMC processor is driven by a waveform generator through a single sideband (SSB) modulator. The output of the coherent demodulator is composed of positive and negative pulses, which are the envelopes of the chirp transform processor output. These pulses correspond to the data symbols. Following the demodulator, a logic circuit reconstructs the pulses into data, which are subsequently differentially decoded to form the transmitted data. The coherent demodulation and detection of BPSK signals derived from a CMC chirp transform processor were experimentally demonstrated and bit error rate (BER) testing was performed. To assess the feasibility of such advanced receiver, the results were compared with the theoretical analysis and plotted for an average BER as a function of signal-to-noise ratio. Another goal of this SBIR program was the development of a commercial product. The commercial product developed was an arbitrary waveform generator. The successful sales have begun with the delivery of the first arbitrary waveform generator.

  12. Optical analysis and thermal management of 2-cell strings linear concentrating photovoltaic system

    NASA Astrophysics Data System (ADS)

    Reddy, K. S.; Kamnapure, Nikhilesh R.

    2015-09-01

    This paper presents the optical and thermal analyses for a linear concentrating photovoltaic/thermal collector under different operating conditions. Linear concentrating photovoltaic system (CPV) consists of a highly reflective mirror, a receiver and semi-dual axis tracking mechanism. The CPV receiver embodies two strings of triple-junction cells (100 cells in each string) adhered to a mild steel circular tube mounted at the focal length of trough. This system provides 560 W of electricity and 1580 W of heat which needs to be dissipated by active cooling. The Al2O3/Water nanofluid is used as heat transfer fluid (HTF) flowing through circular receiver for CPV cells cooling. Optical analysis of linear CPV system with 3.35 m2 aperture and geometric concentration ratio (CR) of 35 is carried out using Advanced System Analysis Program (ASAP) an optical simulation tool. Non-uniform intensity distribution model of solar disk is used to model the sun in ASAP. The impact of random errors including slope error (σslope), tracking error (σtrack) and apparent change in sun's width (σsun) on optical performance of collector is shown. The result from the optical simulations shows the optical efficiency (ηo) of 88.32% for 2-cell string CPV concentrator. Thermal analysis of CPV receiver is carried out with conjugate heat transfer modeling in ANSYS FLUENT-14. Numerical simulations of Al2O3/Water nanofluid turbulent forced convection are performed for various parameters such as nanoparticle volume fraction (φ), Reynolds number (Re). The addition of the nanoparticle in water enhances the heat transfer in the ranges of 3.28% - 35.6% for φ = 1% - 6%. Numerical results are compared with literature data which shows the reasonable agreement.

  13. Advanced space transportation systems

    NASA Technical Reports Server (NTRS)

    Disher, J. H.; Hethcoat, J. P.; Page, M. A.

    1981-01-01

    Projected growth in space transportation capabilities beyond the initial Space Shuttle is discussed in terms of earth-to-low-orbit launch vehicles as well as transportation beyond low orbit (orbit transfer vehicles). Growth versions of the Shuttle and heavy-lift derivatives of the Shuttle are shown conceptually. More advanced launch vehicle concepts are also shown, based on rocket propulsion or combinations of rocket and air-breathing propulsion. Orbit transfer vehicle concepts for personnel transport and for cargo transport are discussed, including chemical rocket as well as electric propulsion. Finally, target levels of capability and efficiencies for later time periods are discussed and compared with the prospective vehicle concepts mentioned earlier.

  14. NREL Photovoltaic Research -- Extensive Capabilities and Experience Under One Roof

    SciTech Connect

    2016-08-01

    NREL's high-impact photovoltaic successes in fundamental research, advanced materials and devices, and technology development contribute to: 1) boosting solar cell conversion efficiencies, 2) Lowering the cost of solar cells, modules, and systems, and 3) improving the reliability of photovoltaic (PV) components and systems.

  15. NASA Advanced Exploration Systems: Advancements in Life Support Systems

    NASA Technical Reports Server (NTRS)

    Shull, Sarah A.; Schneider, Walter F.

    2016-01-01

    The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions assessed by NASA’s Habitability Architecture Team.

  16. Hybrid photovoltaic-thermoelectric system for concentrated solar energy conversion: Experimental realization and modeling

    NASA Astrophysics Data System (ADS)

    Beeri, Ofer; Rotem, Oded; Hazan, Eden; Katz, Eugene A.; Braun, Avi; Gelbstein, Yaniv

    2015-09-01

    An experimental demonstration of the combined photovoltaic (PV) and thermoelectric conversion of concentrated sunlight (with concentration factor, X, up to ˜300) into electricity is presented. The hybrid system is based on a multi-junction PV cell and a thermoelectric generator (TEG). The latter increases the electric power of the system and dissipates some of the excessive heat. For X ≤ 200, the system's maximal efficiency, ˜32%, was mostly due to the contribution from the PV cell. With increasing X and system temperature, the PV cell's efficiency decreased while that of the TEG increased. Accordingly, the direct electrical contribution of the TEG started to dominate in the total system power, reaching ˜20% at X ≈ 290. Using a simple steady state finite element modeling, the cooling effect of the TEG on the hybrid system's efficiency was proved to be even more significant than its direct electrical contribution for high solar concentrations. As a result, the total efficiency contribution of the TEG reached ˜40% at X ≈ 200. This suggests a new system optimization concept that takes into account the PV cell's temperature dependence and the trade-off between the direct electrical generation and cooling capabilities of the TEG. It is shown that the hybrid system has a real potential to exceed 50% total efficiency by using more advanced PV cells and TE materials.

  17. Federal policies to promote the widespread utilization of photovoltaic systems. Supplement: review and critique

    SciTech Connect

    Smith, J.L.

    1980-04-15

    This document is intended as a supplement to the two-volume report entitled Federal Policies to Promote the Widespread Utilization of Photovoltaic Systems that was submitted to Congress by the Department of Energy in February and April of 1980. This supplement contains review comments prepared by knowledgeable experts who reviewed early drafts of the Congressional report. Responses to the review comments by the Jet Propulsion Laboratory, preparer of the Congressional report, are also included in this supplement. The Congressional report, mandated in the Solar Photovoltaic Energy Research, Development, and Demonstration Act of 1978 (P.L. 95-590), discusses various issues related to promoting the deployment of photovoltaic systems through the Federal Photovoltaic Program. Various program strategies and funding levels are examined.

  18. Advanced Microdisplays for Portable Systems

    DTIC Science & Technology

    1999-08-01

    THROUGH SCIENCE mm WE DEFEND TECHNICAL REPORT NATICK/TR-99/037 AD ADVANCED MICRODISPLAYS FOR PORTABLE SYSTEMS by Phillip Alvelda Michael...1996 - 19 October 1998 4. TITLE AND SUBTITLE ADVANCED MICRODISPLAYS FOR PORTABLE SYSTEMS 6. AUTHOR(S) Phillip Alvelda , Michael Bolotski, Ramon...MIT’s Artificial Intelligence Laboratory which forms the basis for this proposal. Under DARPA funding, Mr. Alvelda and Mr. Knight developed the highest

  19. Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Presentation)

    SciTech Connect

    Miller, D. C.; Muller, M.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

    2012-03-01

    Many concentrating photovoltaic (CPV) systems use a polymeric encapsulant to couple and optical component and/or coverglass to the cell. In that location, the encapsulation improves the transmission of concentrated optical flux through interface(s), while protecting the cell from the environment. The durability of encapsulation materials, however, is not well established relative to the desired service life of 30 years. Therefore, we have initiated a screen test to identify the field-induced failure modes for a variety of popular PV encapsulation materials. An existing CPV module (with no PV cells present) was modified to accommodate encapsulation specimens. The module (where nominal concentration of solar flux is 500x for the domed-Fresnel design) has been mounted on a tracker in Golden, CO (elevation 1.79 km). Initial results are reported here for 18 months cumulative exposure, including the hottest and coldest months of the past year. Characteristics observed at intervals during that time include: visual appearance, direct and hemispherical transmittance, and mass. Degradation may be assessed from subsequent analysis (including yellowness index and cut-on frequency) relative to the ambient conditions present during field exposure. The fluorescence signature observed of all the silicone specimens is examined here, including possible factors of causation -- the platinum catalyst used in the addition cured materials as well as the primer used to promote adhesion to the quartz substrate and superstrate.

  20. Stand-alone flat-plate photovoltaic power systems: System sizing and life-cycle costing methodology for Federal agencies

    NASA Technical Reports Server (NTRS)

    Borden, C. S.; Volkmer, K.; Cochrane, E. H.; Lawson, A. C.

    1984-01-01

    A simple methodology to estimate photovoltaic system size and life-cycle costs in stand-alone applications is presented. It is designed to assist engineers at Government agencies in determining the feasibility of using small stand-alone photovoltaic systems to supply ac or dc power to the load. Photovoltaic system design considerations are presented as well as the equations for sizing the flat-plate array and the battery storage to meet the required load. Cost effectiveness of a candidate photovoltaic system is based on comparison with the life-cycle cost of alternative systems. Examples of alternative systems addressed are batteries, diesel generators, the utility grid, and other renewable energy systems.

  1. An Operating Method Using Prediction of Photovoltaic Power for a Photovoltaic-Diesel Hybrid Power Generation System

    NASA Astrophysics Data System (ADS)

    Yamamoto, Shigehiro; Sumi, Kazuyoshi; Nishikawa, Eiichi; Hashimoto, Takeshi

    This paper describes a novel operating method using prediction of photovoltaic (PV) power for a photovoltaic-diesel hybrid power generation system. The system is composed of a PV array, a storage battery, a bi-directional inverter and a diesel engine generator (DG). The proposed method enables the system to save fuel consumption by using PV energy effectively, reducing charge and discharge energy of the storage battery, and avoiding low-load operation of the DG. The PV power is simply predicted from a theoretical equation of solar radiation and the observed PV energy for a constant time before the prediction. The amount of fuel consumption of the proposed method is compared with that of other methods by a simulation based on measurement data of the PV power at an actual PV generation system for one year. The simulation results indicate that the amount of fuel consumption of the proposed method is smaller than that of any other methods, and is close to that of the ideal operation of the DG.

  2. Advanced training systems

    NASA Technical Reports Server (NTRS)

    Savely, Robert T.; Loftin, R. Bowen

    1990-01-01

    Training is a major endeavor in all modern societies. Common training methods include training manuals, formal classes, procedural computer programs, simulations, and on-the-job training. NASA's training approach has focussed primarily on on-the-job training in a simulation environment for both crew and ground based personnel. NASA must explore new approaches to training for the 1990's and beyond. Specific autonomous training systems are described which are based on artificial intelligence technology for use by NASA astronauts, flight controllers, and ground based support personnel that show an alternative to current training systems. In addition to these specific systems, the evolution of a general architecture for autonomous intelligent training systems that integrates many of the features of traditional training programs with artificial intelligence techniques is presented. These Intelligent Computer Aided Training (ICAT) systems would provide much of the same experience that could be gained from the best on-the-job training.

  3. LCP- LIFETIME COST AND PERFORMANCE MODEL FOR DISTRIBUTED PHOTOVOLTAIC SYSTEMS

    NASA Technical Reports Server (NTRS)

    Borden, C. S.

    1994-01-01

    The Lifetime Cost and Performance (LCP) Model was developed to assist in the assessment of Photovoltaic (PV) system design options. LCP is a simulation of the performance, cost, and revenue streams associated with distributed PV power systems. LCP provides the user with substantial flexibility in specifying the technical and economic environment of the PV application. User-specified input parameters are available to describe PV system characteristics, site climatic conditions, utility purchase and sellback rate structures, discount and escalation rates, construction timing, and lifetime of the system. Such details as PV array orientation and tilt angle, PV module and balance-of-system performance attributes, and the mode of utility interconnection are user-specified. LCP assumes that the distributed PV system is utility grid interactive without dedicated electrical storage. In combination with a suitable economic model, LCP can provide an estimate of the expected net present worth of a PV system to the owner, as compared to electricity purchased from a utility grid. Similarly, LCP might be used to perform sensitivity analyses to identify those PV system parameters having significant impact on net worth. The user describes the PV system configuration to LCP via the basic electrical components. The module is the smallest entity in the PV system which is modeled. A PV module is defined in the simulation by its short circuit current, which varies over the system lifetime due to degradation and failure. Modules are wired in series to form a branch circuit. Bypass diodes are allowed between modules in the branch circuits. Branch circuits are then connected in parallel to form a bus. A collection of buses is connected in parallel to form an increment to capacity of the system. By choosing the appropriate series-parallel wiring design, the user can specify the current, voltage, and reliability characteristics of the system. LCP simulation of system performance is site

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

    ERIC Educational Resources Information Center

    Delta Vocational Technical School, Marked Tree, AR.

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

  5. US manufacturers of commercially available stand-alone photovoltaic lighting systems

    SciTech Connect

    McNutt, P

    1994-05-01

    This report introduces photovoltaic (PV) lighting systems, gives some specifications for ordering these systems, and provides a list of some of the manufacturers of these systems in the United States. These PV lighting systems are all commercially available. They are stand-alone systems because they are not tied to the electric utility power grid.

  6. Advanced Teleprocessing Systems.

    DTIC Science & Technology

    1984-09-30

    it is assumed that the length of the start-up duration depends on the arrival proccess . Two types of systems are analyzed: 1) A system where the start...complexity of the models (see a detailed discussion of this issue in section 1.1) and the limitations of the available analysis tools have caused research- ers...the models where it is used. The limitation of queueing theory and of other analysis tools do not allow us to easily analyze a system where the events

  7. Quantifying Interannual Variability for Photovoltaic Systems in PVWatts

    SciTech Connect

    Ryberg, David Severin; Freeman, Janine; Blair, Nate

    2015-10-01

    The National Renewable Energy Laboratory's (NREL's) PVWatts is a relatively simple tool used by industry and individuals alike to easily estimate the amount of energy a photovoltaic (PV) system will produce throughout the course of a typical year. PVWatts Version 5 has previously been shown to be able to reasonably represent an operating system's output when provided with concurrent weather data, however this type of data is not available when estimating system output during future time frames. For this purpose PVWatts uses weather data from typical meteorological year (TMY) datasets which are available on the NREL website. The TMY files represent a statistically 'typical' year which by definition excludes anomalous weather patterns and as a result may not provide sufficient quantification of project risk to the financial community. It was therefore desired to quantify the interannual variability associated with TMY files in order to improve the understanding of risk associated with these projects. To begin to understand the interannual variability of a PV project, we simulated two archetypal PV system designs, which are common in the PV industry, in PVWatts using the NSRDB's 1961-1990 historical dataset. This dataset contains measured hourly weather data and spans the thirty years from 1961-1990 for 239 locations in the United States. To note, this historical dataset was used to compose the TMY2 dataset. Using the results of these simulations we computed several statistical metrics which may be of interest to the financial community and normalized the results with respect to the TMY energy prediction at each location, so that these results could be easily translated to similar systems. This report briefly describes the simulation process used and the statistical methodology employed for this project, but otherwise focuses mainly on a sample of our results. A short discussion of these results is also provided. It is our hope that this quantification of the

  8. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, Tuan

    1997-01-01

    A method and apparatus for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition.

  9. Flight Experience from Space Photovoltaic Concentrator Arrays and its Implication on Terrestrial Concentrator Systems

    NASA Technical Reports Server (NTRS)

    Piszczor, Michael F., Jr.

    2003-01-01

    Nearly all photovoltaic solar arrays flown in space have used a planar (non- concentrating) design. However, there have been a few notable exceptions where photovoltaic concentrators have been tested and used as the mission s primary power source. Among these are the success experienced by the SCARLET (Solar Concentrator Array with Refractive Linear Element Technology) concept used to power NASA's Deep Space 1 mission and the problems encountered by the original Boeing 702 reflective trough concentrator design. This presentation will give a brief overview of past photovoltaic concentrator systems that have flown in space, specifically addressing the valuable lessons learned from flight experience, and other viable concentrator concepts that are being proposed for the future. The general trends of this flight experience will be noted and discussed with regard to its implications on terrestrial photovoltaic concentrator designs.

  10. A pulse-width modulated, high reliability charge controller for small photovoltaic systems

    SciTech Connect

    Gerken, K.; Welsh, D.

    1997-02-01

    This report presents the results of a development effort to design, test and begin production of a new class of small photovoltaic (PV) charge controllers. Sandia National Laboratories provided technical support, test data and financial support through a Balance-of-System Development contract. One of the objectives of the development was to increase user confidence in small PV systems by improving the reliability and operating life of the system controllers. Another equally important objective was to improve the economics of small PV systems by extending the battery lifetimes. Using new technology and advanced manufacturing techniques, these objectives were accomplished. Because small stand-alone PV systems account for over one third of all PV modules shipped, the positive impact of improving the reliability and economics of PV systems in this market segment will be felt throughout the industry. The results of verification testing of the new product are also included in this report. The initial design goals and specifications were very aggressive, but the extensive testing demonstrates that all the goals were achieved. Production of the product started in May at a rate of 2,000 units per month. Over 40 Morningstar distributors (5 US and 35 overseas) have taken delivery in the first 2 months of shipments. Initial customer reactions to the new controller have been very favorable.

  11. Experimental investigation of static ice refrigeration air conditioning system driven by distributed photovoltaic energy system

    NASA Astrophysics Data System (ADS)

    Xu, Y. F.; Li, M.; Luo, X.; Wang, Y. F.; Yu, Q. F.; Hassanien, R. H. E.

    2016-08-01

    The static ice refrigeration air conditioning system (SIRACS) driven by distributed photovoltaic energy system (DPES) was proposed and the test experiment have been investigated in this paper. Results revealed that system energy utilization efficiency is low because energy losses were high in ice making process of ice slide maker. So the immersed evaporator and co-integrated exchanger were suggested in system structure optimization analysis and the system COP was improved nearly 40%. At the same time, we have researched that ice thickness and ice super-cooled temperature changed along with time and the relationship between system COP and ice thickness was obtained.

  12. Photovoltaic-system costing-methodology development. Final report

    SciTech Connect

    Not Available

    1982-07-01

    Presented are the results of a study to expand the use of standardized costing methodologies in the National Photovoltaics Program. The costing standards, which include SAMIS for manufacturing costs and M and D for marketing and distribution costs, have been applied to concentrator collectors and power-conditioning units. The M and D model was also computerized. Finally, a uniform construction cost-accounting structure was developed for use in photovoltaic test and application projects. The appendices contain example cases which demonstrate the use of the models.

  13. Advanced Operating System Technologies

    NASA Astrophysics Data System (ADS)

    Cittolin, Sergio; Riccardi, Fabio; Vascotto, Sandro

    In this paper we describe an R&D effort to define an OS architecture suitable for the requirements of the Data Acquisition and Control of an LHC experiment. Large distributed computing systems are foreseen to be the core part of the DAQ and Control system of the future LHC experiments. Neworks of thousands of processors, handling dataflows of several gigaBytes per second, with very strict timing constraints (microseconds), will become a common experience in the following years. Problems like distributyed scheduling, real-time communication protocols, failure-tolerance, distributed monitoring and debugging will have to be faced. A solid software infrastructure will be required to manage this very complicared environment, and at this moment neither CERN has the necessary expertise to build it, nor any similar commercial implementation exists. Fortunately these problems are not unique to the particle and high energy physics experiments, and the current research work in the distributed systems field, especially in the distributed operating systems area, is trying to address many of the above mentioned issues. The world that we are going to face in the next ten years will be quite different and surely much more interconnected than the one we see now. Very ambitious projects exist, planning to link towns, nations and the world in a single "Data Highway". Teleconferencing, Video on Demend, Distributed Multimedia Applications are just a few examples of the very demanding tasks to which the computer industry is committing itself. This projects are triggering a great research effort in the distributed, real-time micro-kernel based operating systems field and in the software enginering areas. The purpose of our group is to collect the outcame of these different research efforts, and to establish a working environment where the different ideas and techniques can be tested, evaluated and possibly extended, to address the requirements of a DAQ and Control System suitable for LHC

  14. Advanced Data Acquisition Systems

    NASA Technical Reports Server (NTRS)

    Perotti, J.

    2003-01-01

    Current and future requirements of the aerospace sensors and transducers field make it necessary for the design and development of new data acquisition devices and instrumentation systems. New designs are sought to incorporate self-health, self-calibrating, self-repair capabilities, allowing greater measurement reliability and extended calibration cycles. With the addition of power management schemes, state-of-the-art data acquisition systems allow data to be processed and presented to the users with increased efficiency and accuracy. The design architecture presented in this paper displays an innovative approach to data acquisition systems. The design incorporates: electronic health self-check, device/system self-calibration, electronics and function self-repair, failure detection and prediction, and power management (reduced power consumption). These requirements are driven by the aerospace industry need to reduce operations and maintenance costs, to accelerate processing time and to provide reliable hardware with minimum costs. The project's design architecture incorporates some commercially available components identified during the market research investigation like: Field Programmable Gate Arrays (FPGA) Programmable Analog Integrated Circuits (PAC IC) and Field Programmable Analog Arrays (FPAA); Digital Signal Processing (DSP) electronic/system control and investigation of specific characteristics found in technologies like: Electronic Component Mean Time Between Failure (MTBF); and Radiation Hardened Component Availability. There are three main sections discussed in the design architecture presented in this document. They are the following: (a) Analog Signal Module Section, (b) Digital Signal/Control Module Section and (c) Power Management Module Section. These sections are discussed in detail in the following pages. This approach to data acquisition systems has resulted in the assignment of patent rights to Kennedy Space Center under U.S. patent # 6

  15. Advanced Algal Systems Fact Sheet

    SciTech Connect

    2016-06-01

    Research and development (R&D) on advanced algal biofuels and bioproducts presents an opportunity to sustainably expand biomass resource potential in the United States. The Bioenergy Technologies Office’s (BETO’s) Advanced Algal Systems Program is carrying out a long-term, applied R&D strategy to lower the costs of algal biofuel production by working with partners to develop revolutionary technologies and conduct crosscutting analyses to better understand the potential

  16. Advanced imaging communication system

    NASA Technical Reports Server (NTRS)

    Hilbert, E. E.; Rice, R. F.

    1977-01-01

    Key elements of system are imaging and nonimaging sensors, data compressor/decompressor, interleaved Reed-Solomon block coder, convolutional-encoded/Viterbi-decoded telemetry channel, and Reed-Solomon decoding. Data compression provides efficient representation of sensor data, and channel coding improves reliability of data transmission.

  17. Advanced extravehicular protective systems

    NASA Technical Reports Server (NTRS)

    Sutton, J. G.; Heimlich, P. F.; Tepper, E. H.

    1972-01-01

    New technologies are identified and recommended for developing a regenerative portable life support system that provides protection for extravehicular human activities during long duration missions on orbiting space stations, potential lunar bases, and possible Mars landings. Parametric subsystems analyses consider: thermal control, carbon dioxide control, oxygen supply, power supply, contaminant control, humidity control, prime movers, and automatic temperature control.

  18. Advanced synchronous luminescence system

    DOEpatents

    Vo-Dinh, T.

    1997-02-04

    A method and apparatus are disclosed for determining the condition of tissue or otherwise making chemical identifications includes exposing the sample to a light source, and using a synchronous luminescence system to produce a spectrum that can be analyzed for tissue condition. 14 figs.

  19. Power Systems Advanced Research

    SciTech Connect

    California Institute of Technology

    2007-03-31

    In the 17 quarters of the project, we have accomplished the following milestones - first, construction of the three multiwavelength laser scattering machines for different light scattering study purposes; second, build up of simulation software package for simulation of field and laboratory particulates matters data; third, carried out field online test on exhaust from combustion engines with our laser scatter system. This report gives a summary of the results and achievements during the project's 16 quarters period. During the 16 quarters of this project, we constructed three multiwavelength scattering instruments for PM2.5 particulates. We build up a simulation software package that could automate the simulation of light scattering for different combinations of particulate matters. At the field test site with our partner, Alturdyne, Inc., we collected light scattering data for a small gas turbine engine. We also included the experimental data feedback function to the simulation software to match simulation with real field data. The PM scattering instruments developed in this project involve the development of some core hardware technologies, including fast gated CCD system, accurately triggered Passively Q-Switched diode pumped lasers, and multiwavelength beam combination system. To calibrate the scattering results for liquid samples, we also developed the calibration system which includes liquid PM generator and size sorting instrument, i.e. MOUDI. In this report, we give the concise summary report on each of these subsystems development results.

  20. An empirical study on energy efficiency improvement through photovoltaic systems and a LED lighting control system

    NASA Astrophysics Data System (ADS)

    Choi, Young Kwan; Lee, Jae Hyeong

    2015-09-01

    In this research, a facility was constructed and its performance was analyzed to improve the energy efficiency of a vertical-type water treatment building. After the design and construction of a fixed tilt Photovoltaic in Building (PVIB) on the rooftop using a crystalline silicon solar cell module and photovoltaic generator integrated with the building by using a Building Integrated Photovoltaic System (BIPV), a thin-film module on the rooftop and outer wall of water treatment building, and the generation efficiency was analyzed. Also, a DC distribution was established for use of a brushless DC (BLDC) pump motor, and the existing lighting-facility-based manual on-off method was turned into a system for energy conservation by controlling light emitting diode (LED) through a wireless motion sensor and dimming control. In addition, a Building Energy Management System (BEMS) for a real-time analysis of the energy efficiency for a vertical0type water treatment building was prepared and tested. The vertical-type water treatment building developed in this study is currently operating the BEMS. The vertical-type water treatment building reported in this paper is expected to reduce energy consumption by about 30% compared to existing water treatment systems.

  1. Improvement of photovoltaic pumping systems based on standard frequency converters by means of programmable logic controllers

    SciTech Connect

    Fernandez-Ramos, Jose; Narvarte-Fernandez, Luis; Poza-Saura, Fernando

    2010-01-15

    Photovoltaic pumping systems (PVPS) based on standard frequency converters (SFCs) are currently experiencing a growing interest in pumping programmes implemented in remote areas because of their high performance in terms of component reliability, low cost, high power range and good availability of components virtually anywhere in the world. However, in practical applications there have appeared a number of problems related to the adaptation of the SFCs to the requirements of the photovoltaic pumping systems (PVPS). Another disadvantage of dedicated PVPS is the difficulty in implementing maximum power point tracking (MPPT). This paper shows that these problems can be solved through the addition of a basic industrial programmable logic controller (PLC) to the system. This PLC does not increase the cost and complexity of the system, but improves the adaptation of the SFC to the photovoltaic pumping system, and increases the overall performance of the system. (author)

  2. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Mcgough, J.; Moses, K.; Klafin, J. F.

    1982-01-01

    The architecture, requirements, and system elements of an ultrareliable, advanced flight control system are described. The basic criteria are functional reliability of 10 to the minus 10 power/hour of flight and only 6 month scheduled maintenance. A distributed system architecture is described, including a multiplexed communication system, reliable bus controller, the use of skewed sensor arrays, and actuator interfaces. Test bed and flight evaluation program are proposed.

  3. Session: CSP Advanced Systems -- Advanced Overview (Presentation)

    SciTech Connect

    Mehos, M.

    2008-04-01

    The project description is: (1) it supports crosscutting activities, e.g. advanced optical materials, that aren't tied to a single CSP technology and (2) it supports the 'incubation' of new concepts in preliminary stages of investigation.

  4. Effect of Component Failures on Economics of Distributed Photovoltaic Systems

    SciTech Connect

    Lubin, Barry T.

    2012-02-02

    This report describes an applied research program to assess the realistic costs of grid connected photovoltaic (PV) installations. A Board of Advisors was assembled that included management from the regional electric power utilities, as well as other participants from companies that work in the electric power industry. Although the program started with the intention of addressing effective load carrying capacity (ELCC) for utility-owned photovoltaic installations, results from the literature study and recommendations from the Board of Advisors led investigators to the conclusion that obtaining effective data for this analysis would be difficult, if not impossible. The effort was then re-focused on assessing the realistic costs and economic valuations of grid-connected PV installations. The 17 kW PV installation on the University of Hartford's Lincoln Theater was used as one source of actual data. The change in objective required a more technically oriented group. The re-organized working group (changes made due to the need for more technically oriented participants) made site visits to medium-sized PV installations in Connecticut with the objective of developing sources of operating histories. An extensive literature review helped to focus efforts in several technical and economic subjects. The objective of determining the consequences of component failures on both generation and economic returns required three analyses. The first was a Monte-Carlo-based simulation model for failure occurrences and the resulting downtime. Published failure data, though limited, was used to verify the results. A second model was developed to predict the reduction in or loss of electrical generation related to the downtime due to these failures. Finally, a comprehensive economic analysis, including these failures, was developed to determine realistic net present values of installed PV arrays. Two types of societal benefits were explored, with quantitative valuations developed for

  5. High-Performance Home Technologies: Solar Thermal & Photovoltaic Systems

    SciTech Connect

    Baechler, M.; Gilbride, T.; Ruiz, K.; Steward, H.; Love, P.

    2007-06-01

    This document is the sixth volume of the Building America Best Practices Series. It presents information that is useful throughout the United States for enhancing the energy efficiency practices in the specific climate zones that are presented in the first five Best Practices volumes. It provides an introduction to current photovoltaic and solar thermal building practices. Information about window selection and shading is included.

  6. Study of multi-megawatt technology needs for photovoltaic space power systems, volume 2

    NASA Technical Reports Server (NTRS)

    Peterson, D. M.; Pleasant, R. L.

    1981-01-01

    Possible missions requiring multimegawatt photovoltaic space power systems in the 1990's time frame and power system technology needs associated with these missions are examined. Four specific task areas were considered: (1) missions requiring power in the 1-10 megawatt average power region; (2) alternative power systems and component technologies; (3) technology goals and sensitivity trades and analyses; and (4) technology recommendations. Specific concepts for photovoltaic power approaches considered were: planar arrays, concentrating arrays, hybrid systems using Rankine engines, thermophotovoltaic approaches; all with various photovoltaic cell component technologies. Various AC/DC power management approaches, and battery, fuel cell, and flywheel energy storage concepts are evaluated. Interactions with the electrical ion engine injection and stationkeeping system are also considered.

  7. Conceptual design and system analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 2: Study results

    NASA Astrophysics Data System (ADS)

    1981-07-01

    A hybrid photovoltaic/solar thermal electric conversion system is described. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems were compared in performance and cost. It is found that hybrid systems potentially competitive with photovoltaic only or solar thermal electric conversion systems. However, hybrid systems do not appear to have a significant advantage on a levelized cost per kilowatt hour basis.

  8. Conceptual design and system-analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 1: Executive summary

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Studies on hybrid photovoltaic/solar thermal electric conversion systems are summarized. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems were compared on performance and cost. Hybrid systems are shown to be competitive with photovoltaic only or solar thermal electric conversion systems, however, hybrid systems do not appear to have a significant advantage on a levelized cost per kilowatt hour basis.

  9. System integration issues of residential solar photovoltaic systems

    NASA Astrophysics Data System (ADS)

    Yamayee, Z. A.; Peschon, J.

    1980-03-01

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

  10. Advanced quantum communication systems

    NASA Astrophysics Data System (ADS)

    Jeffrey, Evan Robert

    Quantum communication provides several examples of communication protocols which cannot be implemented securely using only classical communication. Currently, the most widely known of these is quantum cryptography, which allows secure key exchange between parties sharing a quantum channel subject to an eavesdropper. This thesis explores and extends the realm of quantum communication. Two new quantum communication protocols are described. The first is a new form of quantum cryptography---relativistic quantum cryptography---which increases communication efficiency by exploiting a relativistic bound on the power of an eavesdropper, in addition to the usual quantum mechanical restrictions intrinsic to quantum cryptography. By doing so, we have observed over 170% improvement in communication efficiency over a similar protocol not utilizing relativity. A second protocol, Quantum Orienteering, allows two cooperating parties to communicate a specific direction in space. This application shows the possibility of using joint measurements, or projections onto an entangled state, in order to extract the maximum useful information from quantum bits. For two-qubit communication, the maximal fidelity of communication using only separable operations is 73.6%, while joint measurements can improve the efficiency to 78.9%. In addition to implementing these protocols, we have improved several resources for quantum communication and quantum computing. Specifically, we have developed improved sources of polarization-entangled photons, a low-loss quantum memory for polarization qubits, and a quantum random number generator. These tools may be applied to a wide variety of future quantum and classical information systems.

  11. Advanced Dewatering Systems Development

    SciTech Connect

    R.H. Yoon; G.H. Luttrell

    2008-07-31

    A new fine coal dewatering technology has been developed and tested in the present work. The work was funded by the Solid Fuels and Feedstocks Grand Challenge PRDA. The objective of this program was to 'develop innovative technical approaches to ensure a continued supply of environmentally sound solid fuels for existing and future combustion systems with minimal incremental fuel cost.' Specifically, this solicitation is aimed at developing technologies that can (i) improve the efficiency or economics of the recovery of carbon when beneficiating fine coal from both current production and existing coal slurry impoundments and (ii) assist in the greater utilization of coal fines by improving the handling characteristics of fine coal via dewatering and/or reconstitution. The results of the test work conducted during Phase I of the current project demonstrated that the new dewatering technologies can substantially reduce the moisture from fine coal, while the test work conducted during Phase II successfully demonstrated the commercial viability of this technology. It is believed that availability of such efficient and affordable dewatering technology is essential to meeting the DOE's objectives.

  12. Intermediate photovoltaic system application experiment operational performance report. Volume 4: Beverly High School, Beverly, Mass.

    NASA Astrophysics Data System (ADS)

    1982-01-01

    Performance data are presented for the months of November and December, 1981 for a photovoltaic power supply at a Massachusetts school building. The ata include: monthly and daily electrical energy produced; monthly and daily solar energy received; monthly and daily array efficiency; energy produced as a function of power level, voltage, cell temperature, and hour of the day; input, output, and efficiency of two power conditioner units and for the total power conditioning system; energy supplied by the photovoltaic system to the load during each day and month; photovoltaic system efficiency; capacity factor; daily system availability; monthly and hourly insolation; heating and cooling degree days; number of freeze-thaw cycles per month; monthly and hourly ambient temperature; monthly and hourly wind speed; wind direction distribution; hourly cell temperature; and data acquisition mode and recording interval plot.

  13. Photovoltaic power converter system with a controller configured to actively compensate load harmonics

    DOEpatents

    de Rooij, Michael Andrew; Steigerwald, Robert Louis; Delgado, Eladio Clemente

    2008-12-16

    Photovoltaic power converter system including a controller configured to reduce load harmonics is provided. The system comprises a photovoltaic array and an inverter electrically coupled to the array to generate an output current for energizing a load connected to the inverter and to a mains grid supply voltage. The system further comprises a controller including a first circuit coupled to receive a load current to measure a harmonic current in the load current. The controller includes a second circuit to generate a fundamental reference drawn by the load. The controller further includes a third circuit for combining the measured harmonic current and the fundamental reference to generate a command output signal for generating the output current for energizing the load connected to the inverter. The photovoltaic system may be configured to compensate harmonic currents that may be drawn by the load.

  14. Assessment of the technology required to develop photovoltaic power system for large scale national energy applications

    NASA Technical Reports Server (NTRS)

    Lutwack, R.

    1974-01-01

    A technical assessment of a program to develop photovoltaic power system technology for large-scale national energy applications was made by analyzing and judging the alternative candidate photovoltaic systems and development tasks. A program plan was constructed based on achieving the 10 year objective of a program to establish the practicability of large-scale terrestrial power installations using photovoltaic conversion arrays costing less than $0.50/peak W. Guidelines for the tasks of a 5 year program were derived from a set of 5 year objectives deduced from the 10 year objective. This report indicates the need for an early emphasis on the development of the single-crystal Si photovoltaic system for commercial utilization; a production goal of 5 x 10 to the 8th power peak W/year of $0.50 cells was projected for the year 1985. The developments of other photovoltaic conversion systems were assigned to longer range development roles. The status of the technology developments and the applicability of solar arrays in particular power installations, ranging from houses to central power plants, was scheduled to be verified in a series of demonstration projects. The budget recommended for the first 5 year phase of the program is $268.5M.

  15. Photovoltaic balance of system experience from an engineering design and construction perspective

    SciTech Connect

    Kauffman, W.R.

    1984-05-01

    The BDM Corporation has gained considerable system design, construction, and construction management experience through the installation of numerous energy systems. In the photovoltaic arena, this experience includes the following systems: the ARCO 1 MW Array--A two-axis tracking flat plate central power station installation; the Mississippi County Community College (MC/sup 3/)--A 240 kW hybrid photovoltaic/thermal power system for the MC/sup 3/ college campus; commercial Application of a PV Concentrator (CAPVC)-- A 50 kW roof-mounted hybrid photovoltaic/thermal system installed on the BDM office building; the McClellan Air Force Base Mini-Mart System--A 40 kW ground-mounted flat plate system for a food market in the housing area; the Southwest Photovoltaic Residential Prototype--A 4.7 kW roof-mounted flat plate residential prototype power system; and the Taiwan Energy Research Laboratory (ERL)--A 1 kW roof-mounted flat plate testing system for the Taiwanese ERL. This article focuses on unique design features of the systems, and problems encountered in construction, start-up, and initial operation of the arrays, particularly in the area of balance of system.

  16. Photovoltaic concepts inspired by coherence effects in photosynthetic systems.

    PubMed

    Brédas, Jean-Luc; Sargent, Edward H; Scholes, Gregory D

    2016-12-20

    The past decade has seen rapid advances in our understanding of how coherent and vibronic phenomena in biological photosynthetic systems aid in the efficient transport of energy from light-harvesting antennas to photosynthetic reaction centres. Such coherence effects suggest strategies to increase transport lengths even in the presence of structural disorder. Here we explore how these principles could be exploited in making improved solar cells. We investigate in depth the case of organic materials, systems in which energy and charge transport stand to be improved by overcoming challenges that arise from the effects of static and dynamic disorder - structural and energetic - and from inherently strong electron-vibration couplings. We discuss how solar-cell device architectures can evolve to use coherence-exploiting materials, and we speculate as to the prospects for a coherent energy conversion system. We conclude with a survey of the impacts of coherence and bioinspiration on diverse solar-energy harvesting solutions, including artificial photosynthetic systems.

  17. Photovoltaic concepts inspired by coherence effects in photosynthetic systems

    NASA Astrophysics Data System (ADS)

    Brédas, Jean-Luc; Sargent, Edward H.; Scholes, Gregory D.

    2017-01-01

    The past decade has seen rapid advances in our understanding of how coherent and vibronic phenomena in biological photosynthetic systems aid in the efficient transport of energy from light-harvesting antennas to photosynthetic reaction centres. Such coherence effects suggest strategies to increase transport lengths even in the presence of structural disorder. Here we explore how these principles could be exploited in making improved solar cells. We investigate in depth the case of organic materials, systems in which energy and charge transport stand to be improved by overcoming challenges that arise from the effects of static and dynamic disorder -- structural and energetic -- and from inherently strong electron-vibration couplings. We discuss how solar-cell device architectures can evolve to use coherence-exploiting materials, and we speculate as to the prospects for a coherent energy conversion system. We conclude with a survey of the impacts of coherence and bioinspiration on diverse solar-energy harvesting solutions, including artificial photosynthetic systems.

  18. Basic photovoltaic principles and methods

    SciTech Connect

    Hersch, P.; Zweibel, K.

    1982-02-01

    This book presents a nonmathematical explanation of the theory and design of photovoltaic (PV) solar cells and systems. The basic elements of PV are introduced: the photovoltaic effect, physical aspects of solar cell efficiency, the typical single-crystal silicon solar cell, advances in single-crystal silicon solar cells. This is followed by the designs of systems constructed from individual cells, including possible constructions for putting cells together and the equipment needed for a practical producer of electrical energy. The future of PV is then discussed. (LEW)

  19. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2000-01-01

    The activities of the Advanced Gas Turbine Systems Research (AGRSR) program are described in the quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education) and Research. Items worthy of note are presented in extended bullet format following the appropriate heading.

  20. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-02-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  1. ADVANCED GAS TURBINE SYSTEMS RESEARCH

    SciTech Connect

    Unknown

    2002-04-01

    The activities of the Advanced Gas Turbine Systems Research (AGTSR) program for this reporting period are described in this quarterly report. The report is divided into discussions of Membership, Administration, Technology Transfer (Workshop/Education), Research and Miscellaneous Related Activity. Items worthy of note are presented in extended bullet format following the appropriate heading.

  2. Impact of small-scale storage systems on the photovoltaic penetration potential at the municipal scale

    NASA Astrophysics Data System (ADS)

    Ramirez Camargo, Luis; Dorner, Wolfgang

    2016-04-01

    The yearly cumulated technical energy generation potential of grid-connected roof-top photovoltaic power plants is significantly larger than the demand of domestic buildings in sparsely populated municipalities in central Europe. However, an energy balance with cumulated annual values does not deliver the right picture about the actual potential for photovoltaics since these run on a highly variable energy source as solar radiation. The mismatch between the periods of generation and demand creates hard limitations for the deployment of the theoretical energy generation potential of roof-top photovoltaics. The actual penetration of roof-top photovoltaic is restricted by the energy quality requirements of the grid and/or the available storage capacity for the electricity production beyond the coverage of own demands. In this study we evaluate in how far small-scale storage systems can contribute to increment the grid-connected roof-top photovoltaic penetration in domestic buildings at a municipal scale. To accomplish this, we calculate, in a first step, the total technical roof-top photovoltaic energy generation potential of a municipality in a high spatiotemporal resolution using a procedure that relies on geographic information systems. Posteriorly, we constrain the set of potential photovoltaic plants to the ones that would be necessary to cover the total yearly demand of the municipality. We assume that photovoltaic plants with the highest yearly yield are the ones that should be installed. For this sub-set of photovoltaic plants we consider five scenarios: 1) no storage 2) one 7 kWh battery is installed in every building with a roof-top photovoltaic plant 3) one 10 kWh battery is installed in every building with a roof-top photovoltaic plant 4) one 7 kWh battery is installed in every domestic building in the municipality 5) one 10 kWh battery is installed in every domestic building in the municipality. Afterwards we evaluate the energy balance of the

  3. Low Earth orbit environmental effects on the space station photovoltaic power generation systems

    NASA Technical Reports Server (NTRS)

    Nahra, Henry K.

    1987-01-01

    A summary of the Low Earth Orbital Environment, its impact on the Photovoltaic Power systems of the space station and the solutions implemented to resolve the environmental concerns or issues are described. Low Earth Orbital Environment (LEO) presents several concerns to the Photovoltaic power systems of the space station. These concerns include atomic oxygen interaction with the polymeric substrate of the solar arrays, ionized environment effects on the array operating voltage, the effects of the meteoroids and debris impacts and penetration through the different layers of the solar cells and their circuits, and the high energy particle and radiation effects on the overall solar array performance. Potential solutions to some of the degrading environmental interactions that will provide the photovoltaic power system of the space station with the desired life are also summarized.

  4. Low earth orbit environmental effects on the Space Station photovoltaic power generation systems

    NASA Technical Reports Server (NTRS)

    Nahra, H. K.

    1988-01-01

    A summary of the low earth orbital environment, its impact on the photovoltaic power systems of the Space Station and the solutions implemented to resolve the environmental concerns or issues are described. Low earth orbital environment (LEO) presents several concerns to the photovoltaic power systems of the Space Station. These concerns include atomic oxygen interaction with the polymeric substrate of the solar arrays, ionized environment effects on the array operating voltage, the effects of the meteoroids and debris impacts and penetration through the different layers of the solar cells and their circuits, and the high energy particle and radiation effects on the overall solar array performance. Potential solutions to some of the degrading environmental interactions that will provide the photovoltaic power system of the Space Station with the desired life are also summarized.

  5. Design of a photovoltaic system for a passive design northeast all-electric residence

    NASA Astrophysics Data System (ADS)

    Mehalick, E. M.; Tully, G. F.; Johnson, J.; Parker, J.; Felice, R.

    1982-01-01

    A photovoltaic system was developed and integrated into a passively designed, low energy consuming home suitable for the Northeast region of the country. The selected array size is 4.1 kW and covers 51 square meters of roof area. The design addresses the residential market segment of low energy consuming houses with limited roof area availability for photovoltaic arrays. A direct mount, next generation, larger sized, photovoltaic shingle module is used to reduce installation costs over earlier generation shingle modules. A 4 kW line-commutated inverter is used in the power conversion subsystem, since it is representative of currently available equipment. The complete system and house design are described, including all the pertinent installation and construction drawings. Specific performance results are presented for the Boston and Madison region. The system design presented, coupled with previously completed designs, provide a set of design options expected to be available to residential homeowners in the mid 1980's.

  6. Advanced turboprop testbed systems study

    NASA Technical Reports Server (NTRS)

    Goldsmith, I. M.

    1982-01-01

    The proof of concept, feasibility, and verification of the advanced prop fan and of the integrated advanced prop fan aircraft are established. The use of existing hardware is compatible with having a successfully expedited testbed ready for flight. A prop fan testbed aircraft is definitely feasible and necessary for verification of prop fan/prop fan aircraft integrity. The Allison T701 is most suitable as a propulsor and modification of existing engine and propeller controls are adequate for the testbed. The airframer is considered the logical overall systems integrator of the testbed program.

  7. Advanced Transport Operating Systems Program

    NASA Technical Reports Server (NTRS)

    White, John J.

    1990-01-01

    NASA-Langley's Advanced Transport Operating Systems Program employs a heavily instrumented, B 737-100 as its Transport Systems Research Vehicle (TRSV). The TRSV has been used during the demonstration trials of the Time Reference Scanning Beam Microwave Landing System (TRSB MLS), the '4D flight-management' concept, ATC data links, and airborne windshear sensors. The credibility obtainable from successful flight test experiments is often a critical factor in the granting of substantial commitments for commercial implementation by the FAA and industry. In the case of the TRSB MLS, flight test demonstrations were decisive to its selection as the standard landing system by the ICAO.

  8. Advanced Information Processing System (AIPS)

    NASA Technical Reports Server (NTRS)

    Pitts, Felix L.

    1993-01-01

    Advanced Information Processing System (AIPS) is a computer systems philosophy, a set of validated hardware building blocks, and a set of validated services as embodied in system software. The goal of AIPS is to provide the knowledgebase which will allow achievement of validated fault-tolerant distributed computer system architectures, suitable for a broad range of applications, having failure probability requirements of 10E-9 at 10 hours. A background and description is given followed by program accomplishments, the current focus, applications, technology transfer, FY92 accomplishments, and funding.

  9. Development of a microprocessor controller for stand-alone photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Millner, A. R.; Kaufman, D. L.

    1984-06-01

    A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

  10. Development of a microprocessor controller for stand-alone photovoltaic power systems

    NASA Technical Reports Server (NTRS)

    Millner, A. R.; Kaufman, D. L.

    1984-01-01

    A controller for stand-alone photovoltaic systems has been developed using a low power CMOS microprocessor. It performs battery state of charge estimation, array control, load management, instrumentation, automatic testing, and communications functions. Array control options are sequential subarray switching and maximum power control. A calculator keypad and LCD display provides manual control, fault diagnosis and digital multimeter functions. An RS-232 port provides data logging or remote control capability. A prototype 5 kW unit has been built and tested successfully. The controller is expected to be useful in village photovoltaic power systems, large solar water pumping installations, and other battery management applications.

  11. Microprocessor-based control of the photovoltaic solar power system for an AM radio station

    SciTech Connect

    Much, C. H.; Rothenheber, P. J.

    1980-01-01

    A microprocessor-based controller for a 15 kW photovoltaic power system powering an AM radio station keeps dc bus voltage between desired limits, governs battery operation, monitors safety conditions, and provides status reporting. The microprocessor also facilitates complicated algorithms that improve performance. The first three months of system operation are presented.

  12. A Review on Suitable Standards for Hybrid Photovoltaic/Thermal Systems

    NASA Astrophysics Data System (ADS)

    Vivar, Marta; Clarke, Matthew; Ratcliff, Tom; Everett, Vernie

    2011-12-01

    This paper will present an evaluation of the available standards and their considerations when using active-cooled CPV systems, along with an initial assessment of the most appropriate tests, including additional test requirements, for hybrid Photovoltaic-Thermal (PV-T) systems in order to guarantee their long-time electrical and thermal performance.

  13. Reliability-economics analysis models for photovoltaic power systems. Volume 1

    SciTech Connect

    Stember, L.H.; Huss, W.R.; Bridgman, M.S.

    1982-11-01

    This report describes the development of modeling techniques to characterize the reliability, availability, and maintenance costs of photovoltaic power systems. The developed models can be used by designers of PV systems in making design decisions and trade-offs to minimize life-cycle energy costs.

  14. Building-Integrated Photovoltaics (BIPV) in the Residential Sector: An Analysis of Installed Rooftop System Prices

    SciTech Connect

    James, T.; Goodrich, A.; Woodhouse, M.; Margolis, R.; Ong, S.

    2011-11-01

    For more than 30 years, there have been strong efforts to accelerate the deployment of solar-electric systems by developing photovoltaic (PV) products that are fully integrated with building materials. This report examines the status of building-integrated PV (BIPV), with a focus on the cost drivers of residential rooftop systems, and explores key opportunities and challenges in the marketplace.

  15. Dynamic hybrid life cycle assessment of energy and carbon of multicrystalline silicon photovoltaic systems.

    PubMed

    Zhai, Pei; Williams, Eric D

    2010-10-15

    This paper advances the life cycle assessment (LCA) of photovoltaic systems by expanding the boundary of the included processes using hybrid LCA and accounting for the technology-driven dynamics of embodied energy and carbon emissions. Hybrid LCA is an extended method that combines bottom-up process-sum and top-down economic input-output (EIO) methods. In 2007, the embodied energy was 4354 MJ/m(2) and the energy payback time (EPBT) was 2.2 years for a multicrystalline silicon PV system under 1700 kWh/m(2)/yr of solar radiation. These results are higher than those of process-sum LCA by approximately 60%, indicating that processes excluded in process-sum LCA, such as transportation, are significant. Even though PV is a low-carbon technology, the difference between hybrid and process-sum results for 10% penetration of PV in the U.S. electrical grid is 0.13% of total current grid emissions. Extending LCA from the process-sum to hybrid analysis makes a significant difference. Dynamics are characterized through a retrospective analysis and future outlook for PV manufacturing from 2001 to 2011. During this decade, the embodied carbon fell substantially, from 60 g CO(2)/kWh in 2001 to 21 g/kWh in 2011, indicating that technological progress is realizing reductions in embodied environmental impacts as well as lower module price.

  16. Advanced Space Fission Propulsion Systems

    NASA Technical Reports Server (NTRS)

    Houts, Michael G.; Borowski, Stanley K.

    2010-01-01

    Fission has been considered for in-space propulsion since the 1940s. Nuclear Thermal Propulsion (NTP) systems underwent extensive development from 1955-1973, completing 20 full power ground tests and achieving specific impulses nearly twice that of the best chemical propulsion systems. Space fission power systems (which may eventually enable Nuclear Electric Propulsion) have been flown in space by both the United States and the Former Soviet Union. Fission is the most developed and understood of the nuclear propulsion options (e.g. fission, fusion, antimatter, etc.), and fission has enjoyed tremendous terrestrial success for nearly 7 decades. Current space nuclear research and technology efforts are focused on devising and developing first generation systems that are safe, reliable and affordable. For propulsion, the focus is on nuclear thermal rockets that build on technologies and systems developed and tested under the Rover/NERVA and related programs from the Apollo era. NTP Affordability is achieved through use of previously developed fuels and materials, modern analytical techniques and test strategies, and development of a small engine for ground and flight technology demonstration. Initial NTP systems will be capable of achieving an Isp of 900 s at a relatively high thrust-to-weight ratio. The development and use of first generation space fission power and propulsion systems will provide new, game changing capabilities for NASA. In addition, development and use of these systems will provide the foundation for developing extremely advanced power and propulsion systems capable of routinely and affordably accessing any point in the solar system. The energy density of fissile fuel (8 x 10(exp 13) Joules/kg) is more than adequate for enabling extensive exploration and utilization of the solar system. For space fission propulsion systems, the key is converting the virtually unlimited energy of fission into thrust at the desired specific impulse and thrust

  17. Experimental investigation on the photovoltaic-thermal solar heat pump air-conditioning system on water-heating mode

    SciTech Connect

    Fang, Guiyin; Hu, Hainan; Liu, Xu

    2010-09-15

    An experimental study on operation performance of photovoltaic-thermal solar heat pump air-conditioning system was conducted in this paper. The experimental system of photovoltaic-thermal solar heat pump air-conditioning system was set up. The performance parameters such as the evaporation pressure, the condensation pressure and the coefficient of performance (COP) of heat pump air-conditioning system, the water temperature and receiving heat capacity in water heater, the photovoltaic (PV) module temperature and the photovoltaic efficiency were investigated. The experimental results show that the mean photovoltaic efficiency of photovoltaic-thermal (PV/T) solar heat pump air-conditioning system reaches 10.4%, and can improve 23.8% in comparison with that of the conventional photovoltaic module, the mean COP of heat pump air-conditioning system may attain 2.88 and the water temperature in water heater can increase to 42 C. These results indicate that the photovoltaic-thermal solar heat pump air-conditioning system has better performances and can stably work. (author)

  18. Design handbook for photovoltaic power systems. Volume 1: Simplified methods for utility interconnected systems

    NASA Astrophysics Data System (ADS)

    Gupta, Y. P.; Young, K.

    1981-10-01

    Principles of photovoltaic power system operation and the elements of system design are discussed. Design characteristics and issues (related to site conditions, building architecture, energy use, and economics) which influence PV system design and performance are identified. Economic feasibility and preliminary array sizing for a PV system application are assessed. A system configuration appropriate for the given site, building, and energy application is provided. Standard techniques and concepts of economic evaluation that form the basis for determining cost effective sizes for PV solar arrays are presented. The building energy load data that is required to perform the PV system analyses are characterized. Procedures for estimating residential energy demand are included. The array, estimate performance, and evaluate the economic value of the PV system are sized. Key aspects of system design including module/panel interconnection, array structure, power conditioning, and utility/load interfaces are discussed.

  19. Recent advances in PV systems technology development in Europe

    SciTech Connect

    Imamura, M.; Grottke, M.; Weiss, I.

    1995-11-01

    The objectives of the photovoltaics (PV) systems technology development were to study several aspects of plant design, monitoring, control, operation, and management of different types of photovoltaic plants. Unsolved problems were to be identified and analysed, and guidelines to improve the monitoring system were to be developed. Principal studies are summarized.

  20. Advanced flight control system study

    NASA Technical Reports Server (NTRS)

    Hartmann, G. L.; Wall, J. E., Jr.; Rang, E. R.; Lee, H. P.; Schulte, R. W.; Ng, W. K.

    1982-01-01

    A fly by wire flight control system architecture designed for high reliability includes spare sensor and computer elements to permit safe dispatch with failed elements, thereby reducing unscheduled maintenance. A methodology capable of demonstrating that the architecture does achieve the predicted performance characteristics consists of a hierarchy of activities ranging from analytical calculations of system reliability and formal methods of software verification to iron bird testing followed by flight evaluation. Interfacing this architecture to the Lockheed S-3A aircraft for flight test is discussed. This testbed vehicle can be expanded to support flight experiments in advanced aerodynamics, electromechanical actuators, secondary power systems, flight management, new displays, and air traffic control concepts.

  1. Advanced gas turbine systems program

    SciTech Connect

    Zeh, C.M.

    1995-06-01

    The U.S. Department of Energy (DOE) is sponsoring a program to develop fuel-efficient gas turbine-based power systems with low emissions. DOE`s Office of Fossil Energy (DOE/FE) and Office of Energy Efficiency and Renewable Energy (DOE/EE) have initiated an 8-year program to develop high-efficiency, natural gas-fired advanced gas turbine power systems. The Advanced Turbine Systems (ATS) Program will support full-scale prototype demonstration of both industrial- and utility-scale systems that will provide commercial marketplace entries by the year 2000. When the program targets are met, power system emissions will be lower than from the best technology in use today. Efficiency of the utility-scale units will be greater than 60 percent on a lower heating value basis, and emissions of carbon dioxide will be reduced inversely with this increase. Industrial systems will also see an improvement of at least 15 percent in efficiency. Nitrogen oxides will be reduced by at least 10 percent, and carbon monoxide and hydrocarbon emissions will each be kept below 20 parts per million, for both utility and industrial systems.

  2. Comparison of solar photovoltaic and nuclear reactor power systems for a human-tended lunar observatory

    NASA Technical Reports Server (NTRS)

    Hickman, J. M.; Bloomfield, H. S.

    1989-01-01

    Photovoltaic and nuclear surface power systems were examined at the 20 to 100 kW power level range for use at a human-tended lunar astronomical observatory, and estimates of the power system masses were made. One system, consisting of an SP-100 thermoelectric nuclear power supply integrated with a lunar lander, is recommended for further study due to its low system mass, potential for modular growth, and applicability to other surface power missions, particularly in the Martian system.

  3. Comparison of solar photovoltaic and nuclear reactor power systems for a human-tended lunar observatory

    NASA Technical Reports Server (NTRS)

    Hickman, J. M.; Bloomfield, H. S.

    1989-01-01

    Photovoltaic and nuclear surface power systems were examined at the 20 to 100 kW power level range for use at a human-tended lunar astronomical observatory, andestimates of the power system masses were made. One system, consisting of an SP-100 thermoelectric nuclear power supply integrated with a lunar lander, is recommended for further study due to its low system mass, potential for modular growth, and applicability to other surface power missions, particularly in the Martian system.

  4. U.S. Solar Photovoltaic System Cost Benchmark: Q1 2016

    SciTech Connect

    Fu, Ran; Chung, Donald; Lowder, Travis; Feldman, David; Ardani, Kristen; Margolis, Robert

    2016-09-01

    NREL has been modeling U.S. photovoltaic (PV) system costs since 2009. This report benchmarks costs of U.S. solar PV for residential, commercial, and utility-scale systems built in the first quarter of 2016 (Q1 2016). Our methodology includes bottom-up accounting for all system and project-development costs incurred when installing residential, commercial, and utility-scale systems, and it models the capital costs for such systems.

  5. U.S. Solar Photovoltaic System Cost Benchmark: Q1 2016

    SciTech Connect

    Fu, Ran; Chung, Donald; Lowder, Travis; Feldman, David; Ardani, Kristen; Margolis, Robert

    2016-07-19

    NREL has been modeling U.S. photovoltaic (PV) system costs since 2009. This report benchmarks costs of U.S. solar PV for residential, commercial, and utility-scale systems built in the first quarter of 2016 (Q1 2016). Our methodology includes bottom-up accounting for all system and project-development costs incurred when installing residential, commercial, and utility-scale systems, and it models the capital costs for such systems.

  6. Durability of Polymeric Encapsulation Materials for Concentrating Photovoltaic Systems (Poster)

    SciTech Connect

    Miller, D. C.; Kempe, M. D.; Araki, K.; Kennedy, C. E.; Kurtz, S. R.

    2011-02-01

    Polymeric encapsulation materials are typically used in concentrating photovoltaic (CPV) modules to protect the cell from the field environment. Because it is physically located adjacent to the cell, the encapsulation is exposed to a high optical flux, often including light in the ultraviolet (UV) and infrared (IR) wavelengths. The durability of encapsulants used in CPV modules is critical to the technology, but is presently not well understood. This work seeks to identify the appropriate material types, field-induced failure mechanisms, and factors of influence (if possible) of polymeric encapsulation. These results will ultimately be weighed against those of future qualification and accelerated life test procedures.

  7. Acceptance Testing of a Satellite SCADA Photovoltaic-Diesel Hybrid System

    NASA Technical Reports Server (NTRS)

    Kalu, Alex; Acosta, R.; Durand, S.; Emrich, Carol; Ventre, G.; Wilson, W.

    1999-01-01

    Savannah State University (SSU) and the Florida Solar Energy Center (FSEC) have been participating in the NASA Advanced Communications Technology Satellite (ACTS) program for the last five years. This program was designed by NASA to help maintain U.S. leadership in commercial space communications by funding high-risk research, and to flight-test next-generation digital satellite components. Launched in 1993, ACTS is an U.S. government funded technology test-bed that incorporates high power Ka-band transponders, small spot beams, and on-board digital storage and switching technology. Associated with the spacecraft, is a prototype satellite control center that supports various application experiments. The SSU/FSEC application experiment is to developing a Photovoltaic-Diesel Hybrid Power system complete with satellite Supervisory Control and Data Acquisition (SCADA). The hybrid system was design to demonstrate the feasibility of using SCADA to maintain and operate remote village power systems. This configuration would enable experts at a central location to provide technical assistance to local technicians while they acquire a measure of proficiency with the hybrid system operation and maintenance. Upon full mastery of the technology, similar SCADA arrangement are planned to remotely monitor and control constellation of hybrid systems scattered overlarge rural areas. Two Orion Energy APEX-1000 hybrid systems were delivered in 1998, one was installed at SSU in eastern Georgia and the other was installed at FSEC in Central Florida. The project was designed to: (1) evaluate the performance of ACTS in a SCADA arrangement, (2) monitor the health and performance of all major hybrid subsystems, (3) investigate load control and battery charging strategies to maximize battery capacity and lifetime, and (4) develop satellite communication protocol. Preliminary results indicate that the hybrid design is suitable for satellite Supervisory Control and Data Acquisition. A

  8. SolarTile: A rooftop integrated photovoltaic system. Phase 1, final report

    SciTech Connect

    1998-03-26

    AstroPower, Royal Group Technologies, and Solar Design Associates are jointly developing an integrated photovoltaic roofing system for residential and light commercial building applications. This family of products will rely heavily on the technological development of a roofing tile made from recycled plastic and innovative module fabrication and encapsulation processes in conjunction with an advanced Silicon-Film{trademark} solar cell product. This solar power generating roofing product is presently being referred to as the SolarTile. A conceptual drawing of the solar roofing tile is shown. The SolarTile will be integrated with non-solar tiles in a single roof installation permitting ease of assembly and the ability to use conventional roofing techniques at ridges, valleys, and eaves. The Phase 1 effort included tasks aimed at the development of the proposed product concept; product manufacturing or fabrication, and installation cost estimates; business planning; and a market assessment of the proposed product, including target selling prices, target market sectors, size estimates for each market sector, and planned distribution mechanisms for market penetration. Technical goals as stated in the Phase 1 proposal and relevant progress are reported.

  9. Light Emitting, Photovoltaic or Other Electronic Apparatus and System

    NASA Technical Reports Server (NTRS)

    Ray, William Johnstone (Inventor); Lowenthal, Mark D. (Inventor); Shotton, Neil O. (Inventor); Blanchard, Richard A. (Inventor); Lewandowski, Mark Allan (Inventor); Fuller, Kirk A. (Inventor); Frazier, Donald Odell (Inventor)

    2016-01-01

    The present invention provides an electronic apparatus, such as a lighting device comprised of light emitting diodes (LEDs) or a power generating apparatus comprising photovoltaic diodes, which may be created through a printing process, using a semiconductor or other substrate particle ink or suspension and using a lens particle ink or suspension. An exemplary apparatus comprises a base; at least one first conductor; a plurality of diodes coupled to the at least one first conductor; at least one second conductor coupled to the plurality of diodes; and a plurality of lenses suspended in a polymer deposited or attached over the diodes. The lenses and the suspending polymer have different indices of refraction. In some embodiments, the lenses and diodes are substantially spherical, and have a ratio of mean diameters or lengths between about 10:1 and 2:1. The diodes may be LEDs or photovoltaic diodes, and in some embodiments, have a junction formed at least partially as a hemispherical shell or cap.

  10. Light Emitting, Photovoltaic or Other Electronic Apparatus and System

    NASA Technical Reports Server (NTRS)

    Ray, William Johnstone (Inventor); Lowenthal, Mark D. (Inventor); Shotton, Neil O. (Inventor); Blanchard, Richard A. (Inventor); Lewandowski, Mark Allan (Inventor); Fuller, Kirk A. (Inventor); Frazier, Donald Odell (Inventor)

    2016-01-01

    The present invention provides an electronic apparatus, such as a lighting device comprised of light emitting diodes (LEDs) or a power generating apparatus comprising photovoltaic diodes, which may be created through a printing process, using a semiconductor or other substrate particle ink or suspension and using a lens particle ink or suspension. An exemplary apparatus comprises a base; at least one first conductor; a plurality of substantially spherical or optically resonant diodes coupled to the at least one first conductor; at least one second conductor coupled to the plurality of diodes; and a plurality of substantially spherical lenses suspended in a polymer attached or deposited over the diodes. The lenses and the suspending polymer have different indices of refraction. In some embodiments, the lenses and diodes have a ratio of mean diameters or lengths between about 10:1 and 2:1. The diodes may be LEDs or photovoltaic diodes, and in some embodiments, have a junction formed at least partially as a hemispherical shell or cap.

  11. Light emitting, photovoltaic or other electronic apparatus and system

    NASA Technical Reports Server (NTRS)

    Ray, William Johnstone (Inventor); Lowenthal, Mark D. (Inventor); Shotton, Neil O. (Inventor); Blanchard, Richard A. (Inventor); Lewandowski, Mark Allan (Inventor); Fuller, Kirk A. (Inventor); Frazier, Donald Odell (Inventor)

    2013-01-01

    The present invention provides an electronic apparatus, such as a lighting device comprised of light emitting diodes (LEDs) or a power generating apparatus comprising photovoltaic diodes, which may be created through a printing process, using a semiconductor or other substrate particle ink or suspension and using a lens particle ink or suspension. An exemplary apparatus comprises a base; at least one first conductor; a plurality of diodes coupled to the at least one first conductor; at least one second conductor coupled to the plurality of diodes; and a plurality of lenses suspended in a polymer deposited or attached over the diodes. The lenses and the suspending polymer have different indices of refraction. In some embodiments, the lenses and diodes are substantially spherical, and have a ratio of mean diameters or lengths between about 10:1 and 2:1. The diodes may be LEDs or photovoltaic diodes, and in some embodiments, have a junction formed at least partially as a hemispherical shell or cap.

  12. Light emitting, photovoltaic or other electronic apparatus and system

    NASA Technical Reports Server (NTRS)

    Ray, William Johnstone (Inventor); Lowenthal, Mark D. (Inventor); Shotton, Neil O. (Inventor); Blanchard, Richard A. (Inventor); Lewandowski, Mark Allan (Inventor); Fuller, Kirk A. (Inventor); Frazier, Donald Odell (Inventor)

    2013-01-01

    The present invention provides an electronic apparatus, such as a lighting device comprised of light emitting diodes (LEDs) or a power generating apparatus comprising photovoltaic diodes, which may be created through a printing process, using a semiconductor or other substrate particle ink or suspension and using a lens particle ink or suspension. An exemplary apparatus comprises a base; at least one first conductor; a plurality of substantially spherical or optically resonant diodes coupled to the at least one first conductor; at least one second conductor coupled to the plurality of diodes; and a plurality of substantially spherical lenses suspended in a polymer attached or deposited over the diodes. The lenses and the suspending polymer have different indices of refraction. In some embodiments, the lenses and diodes have a ratio of mean diameters or lengths between about 10:1 and 2:1. The diodes may be LEDs or photovoltaic diodes, and in some embodiments, have a junction formed at least partially as a hemispherical shell or cap.

  13. Arranging social circumstances for spreading photovoltaic power generation systems

    SciTech Connect

    Nakagawa, Koshi; Katsumata, Hiroshi

    1994-12-31

    In 1990, The Comprehensive Energy Investigation Board discussed and set a target for the introduction of new energy sources. The investigation Board prepared the energy supply outlook for the year of 2000 and 2010, and the target for the introduction of new energy sources was a part of the outlook. In the last few years, however, the actual supply of primary energy sources has made a quite different growth from the original outlook due to the current stagnancy in the development of the nuclear power generation and the crude oil prices stabilized at the lower level. Under the circumstances, the outlook has been under review since the spring of this year. In the new outlook, basic policies are being made to expand the use of new energy sources, with the specific target ratio of new energy to the total energy supply of 1.2% in 1992 (actual), 2.0% in 2000, and 3.0% in 2010. Among the new energy sources, the outlook specifies the introduction of the photovoltaic energy, targeting its increase to 400,000 kW by 2000 and 4,600,000 kW by 2010. Thus the supply of the photovoltaic power generation is expected to increase rapidly after the year 2000.

  14. 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.

  15. Photovoltaic device and method

    DOEpatents

    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.

  16. Impacts of Regional Electricity Prices and Building Type on the Economics of Commercial Photovoltaic Systems

    SciTech Connect

    Ong, S.; Campbell, C.; Clark, N.

    2012-12-01

    To identify the impacts of regional electricity prices and building type on the economics of solar photovoltaic (PV) systems, 207 rate structures across 77 locations and 16 commercial building types were evaluated. Results for expected solar value are reported for each location and building type. Aggregated results are also reported, showing general trends across various impact categories.

  17. The NREL Outdoor Accelerated-Weathering Tracking System Photovoltaic Module Exposure Results

    SciTech Connect

    Basso, T. S.

    2000-01-01

    Status results are presented for the Outdoor Accelerated-Weathering Tracking System (OATS) first study on photovoltaic (PV) modules. Studies began in November 1997 on pairs of commercially available crystalline silicon and amorphous silicon (a-Si) PV modules kept at constant resistive load.

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

    NASA Technical Reports Server (NTRS)

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

    1989-01-01

    The development of photovoltaic arrays beyond the next generation is discussed with attention given to the potentials of thin-film polycrystalline and amorphous cells. Of particular importance is the efficiency (the fraction of incident solar energy converted to electricity) and specific power (power to weight ratio). It is found that the radiation tolerance of thin-film materials is far greater than that of single crystal materials. CuInSe2 shows no degradation when exposed to 1-MeV electrons.

  19. Advanced uncooled infrared system electronics

    NASA Astrophysics Data System (ADS)

    Neal, Henry W.

    1998-07-01

    Over the past two decades, Raytheon Systems Company (RSC), formerly Texas Instruments Defense Systems & Electronics Group, developed a robust family of products based on a low- cost, hybrid ferroelectric (FE) uncooled focal-plane array (FPA) aimed at meeting the needs for thermal imaging products across both military and commercial markets. Over the years, RSC supplied uncooled infrared (IR) sensors for applications such as in combat vehicles, man-portable weaponry, personnel helmets, and installation security. Also, various commercial IR systems for use in automobiles, boats, law enforcement, hand-held applications, building/site security, and fire fighting have been developed. These products resulted in a high degree of success where cooled IR platforms are too bulky and costly, and other uncooled implementations are less reliable or lack significant cost advantage. Proof of this great success is found in the large price reductions, the unprecedented monthly production rates, and the wide diversity of products and customers realized in recent years. The ever- changing needs of these existing and potential customers continue to fuel the advancement of both the primary technologies and the production capabilities of uncooled IR systems at RSC. This paper will describe a development project intended to further advance the system electronics capabilities of future uncooled IR products.

  20. A photovoltaic power system in the remote African village of Tangaye, Upper Volta

    NASA Technical Reports Server (NTRS)

    Bifano, W. J.; Ratajczak, A. F.; Martz, J. E.

    1979-01-01

    A photovoltaic (PV) system powering a grain mill and a water pump was installed in the remote West African village of Tangaye, Upper Volta. Village characteristics as well as system design, hardware, installation and operation to date are described. The PV system cost is discussed. A baseline socio-economic study performed and a follow-up study is planned to determine the impact of the system on the villagers.

  1. Common source-multiple load vs. separate source-individual load photovoltaic system

    NASA Technical Reports Server (NTRS)

    Appelbaum, Joseph

    1989-01-01

    A comparison of system performance is made for two possible system setups: (1) individual loads powered by separate solar cell sources; and (2) multiple loads powered by a common solar cell source. A proof for resistive loads is given that shows the advantage of a common source over a separate source photovoltaic system for a large range of loads. For identical loads, both systems perform the same.

  2. Analysis on Dissemination Conditions of Photovoltaics in Japan by Using Energy System Model MARKAL

    NASA Astrophysics Data System (ADS)

    Endo, Eiichi; Ichinohe, Masayuki

    The national target for PV capacity in Japan is 4. 82, GW in 2010, and several PV Roadmaps until 2030 are also described. To achieve the target, several support programs, such as subsidization to capital cost, Green Credit by the Green Power Certification System, buy-back under the Renewable Portfolio Standard low, have been already introduced. Carbon tax is still under consideration, but there are several analyses about possible carbon tax. The purpose of this paper is to analyze PV system sales price and subsidy through buy-back which make photovoltaics cost-competitive with other energy technologies and make the target for PV capacity achievable by 2030 in Japan under an expected carbon tax. For the analysis energy system of Japan is modeled by using MARKAL. Based on the results of analysis, under 6000, JPY/t-C carbon tax, photovoltaics needs subsidy for a while even if we taking both fuel savings and Green Credit into account. For attaining the national target for PV capacity in 2010, photovoltaics needs more expensive buy-back than that in present, but after 2010 necessary buy-back decreases gradually. If 120, JPY/W PV system sales price is attained by 2030, photovoltaics becomes cost-competitive without any supports. Subsidy through buy-back becomes almost unnecessary in 2030, if we can reduce it less than 170, JPY/W. The total necessary buy-back meets peak in 2025. It is much more than ongoing subsidy to capital cost of PV systems, but annual revenue from the assumed carbon tax can finance the annual total necessary buy-back. This means if photovoltaics can attain the targeted PV system sales price, we should support it for a while by spending carbon tax revenue effectively and efficiently.

  3. Market assessment of photovoltaic power systems for agricultural applications in Colombia

    NASA Technical Reports Server (NTRS)

    Steigelmann, W.; Neyeloff, S.

    1981-01-01

    The market potential for photovoltaic systems in the agricultural sector of Colombia is assessed. Consideration was given to over twenty specific livestock production, crop production, and rural services applications requiring less than 15 kW of power without backup power. Analysis revealed that near-term potential exists for photovoltaic technology in applications in coffee depulging, cattle watering, rural domestic users, rural water supply and small irrigation, rural telephones, rural health posts, and vaccine refrigeration. Market size would be in the 1200 to 2500 kWp range in the 1981 to 86 timeframe. Positive factors influencing the market size include a lack of electrical services, potential for developing the Llanos Orientales Territory, high fuel costs in remote areas, balance of system availability, the presence of wealthy land owners, and a large government-sponsored contract for photovoltaic (PV)-powered rural telephone systems. The anticipated eligibility of photovoltaic equipment for loans would be a further positive factor in market potential. Important negative factors include relatively inexpensive energy in developed locations, reliance on hydropower, lack of familiarity with PV equipment, a lack of financing, and established foreign competition in PV technology. Recommendations to American PV manufacturers attempting to develop the Colombian market are given.

  4. Market assessment of photovoltaic power systems for agricultural applications in Colombia

    NASA Astrophysics Data System (ADS)

    Steigelmann, W.; Neyeloff, S.

    1981-11-01

    The market potential for photovoltaic systems in the agricultural sector of Colombia is assessed. Consideration was given to over twenty specific livestock production, crop production, and rural services applications requiring less than 15 kW of power without backup power. Analysis revealed that near-term potential exists for photovoltaic technology in applications in coffee depulging, cattle watering, rural domestic users, rural water supply and small irrigation, rural telephones, rural health posts, and vaccine refrigeration. Market size would be in the 1200 to 2500 kWp range in the 1981 to 86 timeframe. Positive factors influencing the market size include a lack of electrical services, potential for developing the Llanos Orientales Territory, high fuel costs in remote areas, balance of system availability, the presence of wealthy land owners, and a large government-sponsored contract for photovoltaic (PV)-powered rural telephone systems. The anticipated eligibility of photovoltaic equipment for loans would be a further positive factor in market potential. Important negative factors include relatively inexpensive energy in developed locations, reliance on hydropower, lack of familiarity with PV equipment, a lack of financing, and established foreign competition in PV technology. Recommendations to American PV manufacturers attempting to develop the Colombian market are given.

  5. Photovoltaic applications definition and photovoltaic system definition study in the agricultural sector. Volume 3. Appendixes

    NASA Astrophysics Data System (ADS)

    Mengel, R. W.; Nadolski, T. P.; Sparks, D. C.; Young, S. K.; Yingst, A.

    1980-05-01

    A description of energy consumption for representative farm operations, design and simulation of ventilation for livestock shelters; irrigation systems and calculations; and detailed methodology for selecting multifunction PV system applications are presented. Hourly load data for the chosen farm operations; sample linear programming solution output format; life cycle cost calculation; and illustrative monthly load data for applications analysis and equipment data for applications analysis are also discussed.

  6. Evaluation of critical materials for five advanced design photovoltaic cells with an assessment of indium and gallium

    SciTech Connect

    Watts, R.L.; Gurwell, W.E.; Jamieson, W.M.; Long, L.W.; Pawlewicz, W.T.; Smith, S.A.; Teeter, R.R.

    1980-05-01

    The objective of this study is to identify potential material supply constraints due to the large-scale deployment of five advanced photovoltaic (PV) cell designs, and to suggest strategies to reduce the impacts of these production capacity limitations and potential future material shortages. This report presents the results of the screening of the five following advanced PV cell designs: polycrystalline silicon, amorphous silicon, cadmium sulfide/copper sulfide frontwall, polycrystalline gallium arsenide MIS, and advanced concentrator-500X. Each of these five cells is screened individually assuming that they first come online in 1991, and that 25 GWe of peak capacity is online by the year 2000. A second computer screening assumes that each cell first comes online in 1991 and that each cell has 5 GWe of peak capacity by the year 2000, so that the total online cpacity for the five cells is 25 GWe. Based on a review of the preliminary basline screening results, suggestions were made for varying such parameters as the layer thickness, cell production processes, etc. The resulting PV cell characterizations were then screened again by the CMAP computer code. Earlier DOE sponsored work on the assessment of critical materials in PV cells conclusively identtified indium and gallium as warranting further investigation as to their availability. Therefore, this report includes a discussion of the future availability of gallium and indium. (WHK)

  7. Acceptance Testing of a Satellite SCADA Photovoltaic-Diesel Hybrid System

    NASA Technical Reports Server (NTRS)

    Kalu, A.; Emrich, C.; Ventre, G.; Wilson, W.; Acosta, Roberto (Technical Monitor)

    2000-01-01

    Satellite Supervisory Control and Data Acquisition (SCADA) of a Photovoltaic (PV)/diesel hybrid system was tested using NASA's Advanced Communication Technology Satellite (ACTS) and Ultra Small Aperture Terminal (USAT) ground stations. The setup consisted of a custom-designed PV/diesel hybrid system, located at the Florida Solar Energy Center (FSEC), which was controlled and monitored at a "remote" hub via Ka-band satellite link connecting two 1/4 Watt USATs in a SCADA arrangement. The robustness of the communications link was tested for remote monitoring of the health and performance of a PV/diesel hybrid system, and for investigating load control and battery charging strategies to maximize battery capacity and lifetime, and minimize loss of critical load probability. Baseline hardware performance test results demonstrated that continuous two-second data transfers can be accomplished under clear sky conditions with an error rate of less than 1%. The delay introduced by the satellite (1/4 sec) was transparent to synchronization of satellite modem as well as to the PV/diesel-hybrid computer. End-to-end communications link recovery times were less than 36 seconds for loss of power and less than one second for loss of link. The system recovered by resuming operation without any manual intervention, which is important since the 4 dB margin is not sufficient to prevent loss of the satellite link during moderate to heavy rain. Hybrid operations during loss of communications link continued seamlessly but real-time monitoring was interrupted. For this sub-tropical region, the estimated amount of time that the signal fade will exceed the 4 dB margin is about 10%. These results suggest that data rates of 4800 bps and a link margin of 4 dB with a 1/4 Watt transmitter are sufficient for end-to-end operation in this SCADA application.

  8. Demonstration Advanced Avionics System (DAAS), Phase 1

    NASA Technical Reports Server (NTRS)

    Bailey, A. J.; Bailey, D. G.; Gaabo, R. J.; Lahn, T. G.; Larson, J. C.; Peterson, E. M.; Schuck, J. W.; Rodgers, D. L.; Wroblewski, K. A.

    1981-01-01

    Demonstration advanced anionics system (DAAS) function description, hardware description, operational evaluation, and failure mode and effects analysis (FMEA) are provided. Projected advanced avionics system (PAAS) description, reliability analysis, cost analysis, maintainability analysis, and modularity analysis are discussed.

  9. Photovoltaic/thermal system performance index based on the second law

    NASA Astrophysics Data System (ADS)

    Bazques, E. O.; Anand, D. K.

    1984-12-01

    The second law of thermodynamics is used to optimize the performance of residential hybrid photovoltaic/thermal energy system and the associated control system methodology. The system functioned with photovoltaics embedded in flat plate collectors for roof mounting. The thermal energy was captured by a heat pump. The PV/T system component irreversibilities were calculated and a minimum system performance index model was defined, based on the irreversibilities. The model was applied, with meteorological data, to simulate the system performance at three widely space U.S. locations. The control strategy was heavily latitude dependent. Finally, the second law model identified the irreversibilities of the collector and the room enclosures as the areas where improvements would yield the highest efficiency gains.

  10. Study of multi-megawatt technology needs for photovoltaic space power systems. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    Peterson, D. M.; Pleasant, R. L.

    1981-01-01

    Possible missions requiring multimegawatt photovoltaic space power systems in the 1990's time frame and associated power system technology needs are examined. The following concepts for photovoltaic power approaches are considered: planar arrays, concentrating arrays, hybrid systems using Rankine engines, thermophotovoltaic and AC/DC power management approaches, battery, fuel cell, flywheel energy storage, and interactions with the electrical ion engine injection and stationkeeping system. The levels of modularity for efficient, safe, constructable, serviceable, and cost effective system design are analyzed, and the benefits of alternate approaches developed. Both manned low Earth orbit and unmanned geosynchronous Earth orbit applications were examined for technological development. Technology developments applicable to power systems which appear to have benefits independent of the absolute power level are suggested.

  11. NASA Advanced Explorations Systems: Advancements in Life Support Systems

    NASA Technical Reports Server (NTRS)

    Shull, Sarah A.; Schneider, Walter F.

    2016-01-01

    The NASA Advanced Exploration Systems (AES) Life Support Systems (LSS) project strives to develop reliable, energy-efficient, and low-mass spacecraft systems to provide environmental control and life support systems (ECLSS) critical to enabling long duration human missions beyond low Earth orbit (LEO). Highly reliable, closed-loop life support systems are among the capabilities required for the longer duration human space exploration missions assessed by NASA's Habitability Architecture Team (HAT). The LSS project is focused on four areas: architecture and systems engineering for life support systems, environmental monitoring, air revitalization, and wastewater processing and water management. Starting with the international space station (ISS) LSS systems as a point of departure (where applicable), the mission of the LSS project is three-fold: 1. Address discrete LSS technology gaps 2. Improve the reliability of LSS systems 3. Advance LSS systems towards integrated testing on the ISS. This paper summarized the work being done in the four areas listed above to meet these objectives. Details will be given on the following focus areas: Systems Engineering and Architecture- With so many complex systems comprising life support in space, it is important to understand the overall system requirements to define life support system architectures for different space mission classes, ensure that all the components integrate well together and verify that testing is as representative of destination environments as possible. Environmental Monitoring- In an enclosed spacecraft that is constantly operating complex machinery for its own basic functionality as well as science experiments and technology demonstrations, it's possible for the environment to become compromised. While current environmental monitors aboard the ISS will alert crew members and mission control if there is an emergency, long-duration environmental monitoring cannot be done in-orbit as current methodologies

  12. An in-depth review of photovoltaic system performance models

    NASA Technical Reports Server (NTRS)

    Smith, J. H.; Reiter, L. R.

    1984-01-01

    The features, strong points and shortcomings of 10 numerical models commonly applied to assessing photovoltaic performance are discussed. The models range in capabilities from first-order approximations to full circuit level descriptions. Account is taken, at times, of the cell and module characteristics, the orientation and geometry, array-level factors, the power-conditioning equipment, the overall plant performance, O and M effects, and site-specific factors. Areas of improvement and/or necessary extensions are identified for several of the models. Although the simplicity of a model was found not necessarily to affect the accuracy of the data generated, the use of any one model was dependent on the application.

  13. Apparatus for mounting photovoltaic power generating systems on buildings

    DOEpatents

    Russell, Miles C.

    2009-08-18

    Rectangular photovoltaic (PV) modules are mounted on a building roof by mounting stands that are distributed in rows and columns. Each stand comprises a base plate and first and second different height brackets attached to opposite ends of the base plate. Each first and second bracket comprises two module-support members. One end of each module is pivotally attached to and supported by a first module-support member of a first bracket and a second module-support member of another first bracket. At its other end each module rests on but is connected by flexible tethers to module-support members of two different second brackets. The tethers are sized to allow the modules to pivot up away from the module-support members on which they rest to a substantially horizontal position in response to wind uplift forces.

  14. Electromigration in thin-film photovoltaic module metallization systems

    NASA Technical Reports Server (NTRS)

    Wen, L.; Mon, G.; Jetter, E.; Ross, R., Jr.

    1988-01-01

    Electromigration as a possible thin-film module failure mechanism was investigated using several specially made, fully aluminized thin-film photovoltaic (TF-PV) modules. The effect of electromigration, as determined experimentally by measuring increases in electrical resistance across scribe lines, can be expressed as the product of a damage function, which correlates degradation rate with operating conditions such as current density and temperature, and a susceptibility function, which is defined by module design parameters, particularly aluminum purity and the configuration of the intercell region. Experimental measurements and derived acceleration factors suggest that open-circuit failure resulting from electromigration should not be a serious problem in present state-of-the-art TF-PV modules. Nevertheless, significant intercell resistance increases can result from long-term electromigration exposure, especially in future high-efficiency modules. The problem can be alleviated, however, by appropriate metallization applications and/or proper design of the intercell region.

  15. Solar breeder: Energy payback time for silicon photovoltaic systems

    NASA Technical Reports Server (NTRS)

    Lindmayer, J.

    1977-01-01

    The energy expenditures of the prevailing manufacturing technology of terrestrial photovoltaic cells and panels were evaluated, including silicon reduction, silicon refinement, crystal growth, cell processing and panel building. Energy expenditures include direct energy, indirect energy, and energy in the form of equipment and overhead expenses. Payback times were development using a conventional solar cell as a test vehicle which allows for the comparison of its energy generating capability with the energies expended during the production process. It was found that the energy payback time for a typical solar panel produced by the prevailing technology is 6.4 years. Furthermore, this value drops to 3.8 years under more favorable conditions. Moreover, since the major energy use reductions in terrestrial manufacturing have occurred in cell processing, this payback time directly illustrates the areas where major future energy reductions can be made -- silicon refinement, crystal growth, and panel building.

  16. Sensitivities of projected 1980 photovoltaic system costs to major system cost drivers

    NASA Technical Reports Server (NTRS)

    Zimmerman, L. W.; Smith, J. L.

    1984-01-01

    The sensitivity of projected 1990 photovoltaic (PV) system costs to major system cost drivers was examined. It includes: (1) module costs and module efficiencies; (2) area related balance of system (BOS) costs; (3) inverter costs and efficiencies; and (4) module marketing and distribution markups and system integration fees. Recent PV system cost experiences and the high costs of electricity from the systems are reviewed. The 1990 system costs are projected for five classes of PV systems, including four ground mounted 5-MWp systems and one residential 5-kWp system. System cost projections are derived by first projecting costs and efficiencies for all subsystems and components. Sensitivity analyses reveal that reductions in module cost and engineering and system integration fees seem to have the greatest potential for contributing to system cost reduction. Although module cost is clearly the prime candidate for fruitful PV research and development activities, engineering and system integration fees seem to be more amenable to reduction through appropriate choice of system size and market strategy. Increases in inverter and module efficiency yield significant benefits, especially for systems with high area related costs.

  17. Robust nonlinear controller design to improve the stability of a large scale photovoltaic system

    NASA Astrophysics Data System (ADS)

    Islam, Gazi Md. Saeedul

    Recently interest in photovoltaic (PV) power generation systems is increasing rapidly and the installation of large PV systems or large groups of PV systems that are interconnected with the utility grid is accelerating despite their high cost and low efficiency due to environmental issues and depletions of fossil fuels. Most of the photovoltaic (PV) applications are grid connected. Existing power systems may face the stability problems because of the high penetration of PV systems to the grid. Therefore, more stringent grid codes are being imposed by the energy regulatory bodies for grid integration of PV plants. Recent grid codes dictate that PV plants need to stay connected with the power grid during the network faults because of their increased power penetration level. This requires the system to have large disturbance rejection capability to protect the system and provide dynamic grid support. This thesis presents a new control method to enhance the steady-state and transient stabilities of a grid connected large scale photovoltaic (PV) system. A new control coordination scheme is also presented to reduce the power mismatch during the fault condition in order to limit the fault currents, which is one of the salient features of this study. The performance of the overall system is analyzed using laboratory standard power system simulation software PSCAD/EMTDC.

  18. Spectrum splitting metrics and effect of filter characteristics on photovoltaic system performance.

    PubMed

    Russo, Juan M; Zhang, Deming; Gordon, Michael; Vorndran, Shelby; Wu, Yuechen; Kostuk, Raymond K

    2014-03-10

    During the past few years there has been a significant interest in spectrum splitting systems to increase the overall efficiency of photovoltaic solar energy systems. However, methods for comparing the performance of spectrum splitting systems and the effects of optical spectral filter design on system performance are not well developed. This paper addresses these two areas. The system conversion efficiency is examined in detail and the role of optical spectral filters with respect to the efficiency is developed. A new metric termed the Improvement over Best Bandgap is defined which expresses the efficiency gain of the spectrum splitting system with respect to a similar system that contains the highest constituent single bandgap photovoltaic cell. This parameter indicates the benefit of using the more complex spectrum splitting system with respect to a single bandgap photovoltaic system. Metrics are also provided to assess the performance of experimental spectral filters in different spectrum splitting configurations. The paper concludes by using the methodology to evaluate spectrum splitting systems with different filter configurations and indicates the overall efficiency improvement that is possible with ideal and experimental designs.

  19. Advanced System for Process Engineering

    SciTech Connect

    Williams, K. E.; Saus, L. S.; Regenhardt, P. A.

    1992-02-01

    ASPEN (Advanced System for Process Engineering) is a state of the art process simulator and economic evaluation package which was designed for use in engineering fossil energy conversion processes. ASPEN can represent multiphase streams including solids, and handle complex substances such as coal. The system can perform steady state material and energy balances, determine equipment size and cost, and carry out preliminary economic evaluations. It is supported by a comprehensive physical property system for computation of major properties such as enthalpy, entropy, free energy, molar volume, equilibrium ratio, fugacity coefficient, viscosity, thermal conductivity, and diffusion coefficient for specified phase conditions; vapor, liquid, or solid. The properties may be computed for pure components, mixtures, or components in a mixture, as appropriate. The ASPEN Input Language is oriented towards process engineers.

  20. A low-power photovoltaic system with energy storage for radio communications: description and design methodology

    SciTech Connect

    Chapman, C.P.; Chapman, P.D.

    1982-01-01

    A low power photovoltaic system was constructed with approximately 500 amp hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous nonsun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  1. Low-power photovoltaic system with energy storage for radio communications. Description and design methodology

    SciTech Connect

    Chapman, C.P.; Chapman, P.D.; Lewison, A.H.

    1982-01-15

    A low-power photovoltaic system was constructed with approximately 500 amp-hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous no-sun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  2. Design and fabrication of a prototype system for photovoltaic residences in the northeastern United States

    NASA Astrophysics Data System (ADS)

    Millner, A. R.

    1982-08-01

    Plans for an energy-efficient residence for the Northeastern region of the country with a roof-mounted photovoltaic (PV) solar electric power system which would allow two-way power flow between the utility grid and the house are discussed. A full scale working prototype of the PV system was built to evaluate the performance of that system for one year. Described are the residence design, the prototype description, the construction, and the fabrication history through the first year of operation.

  3. Reliability-economics analysis models for photovoltaic power systems. Volume 2. [SOLREL

    SciTech Connect

    Stember, L.H.; Huss, W.R.; Bridgman, M.S.

    1982-11-01

    This report describes the development of modeling techniques to characterize the reliability, availability, and maintenance costs of photovoltaic power systems. The developed models can be used by designers of PV systems in making design decisions and trade-offs to minimize life-cycle energy costs. Three actual intermediate PV system designs were modeled as examples. The input data estimates used and the results of the analyses are presented.

  4. A low-power photovoltaic system with energy storage for radio communications: Description and design methodology

    NASA Technical Reports Server (NTRS)

    Chapman, C. P.; Chapman, P. D.; Lewison, A. H.

    1982-01-01

    A low power photovoltaic system was constructed with approximately 500 amp hours of battery energy storage to provide power to an emergency amateur radio communications center. The system can power the communications center for about 72 hours of continuous nonsun operation. Complete construction details and a design methodology algorithm are given with abundant engineering data and adequate theory to allow similar systems to be constructed, scaled up or down, with minimum design effort.

  5. Advanced Land Imager Assessment System

    NASA Technical Reports Server (NTRS)

    Chander, Gyanesh; Choate, Mike; Christopherson, Jon; Hollaren, Doug; Morfitt, Ron; Nelson, Jim; Nelson, Shar; Storey, James; Helder, Dennis; Ruggles, Tim; Kaita, Ed; Levy, Raviv; Ong, Lawrence; Markham, Brian; Schweiss, Robert

    2008-01-01

    The Advanced Land Imager Assessment System (ALIAS) supports radiometric and geometric image processing for the Advanced Land Imager (ALI) instrument onboard NASA s Earth Observing-1 (EO-1) satellite. ALIAS consists of two processing subsystems for radiometric and geometric processing of the ALI s multispectral imagery. The radiometric processing subsystem characterizes and corrects, where possible, radiometric qualities including: coherent, impulse; and random noise; signal-to-noise ratios (SNRs); detector operability; gain; bias; saturation levels; striping and banding; and the stability of detector performance. The geometric processing subsystem and analysis capabilities support sensor alignment calibrations, sensor chip assembly (SCA)-to-SCA alignments and band-to-band alignment; and perform geodetic accuracy assessments, modulation transfer function (MTF) characterizations, and image-to-image characterizations. ALIAS also characterizes and corrects band-toband registration, and performs systematic precision and terrain correction of ALI images. This system can geometrically correct, and automatically mosaic, the SCA image strips into a seamless, map-projected image. This system provides a large database, which enables bulk trending for all ALI image data and significant instrument telemetry. Bulk trending consists of two functions: Housekeeping Processing and Bulk Radiometric Processing. The Housekeeping function pulls telemetry and temperature information from the instrument housekeeping files and writes this information to a database for trending. The Bulk Radiometric Processing function writes statistical information from the dark data acquired before and after the Earth imagery and the lamp data to the database for trending. This allows for multi-scene statistical analyses.

  6. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    NASA Astrophysics Data System (ADS)

    Philippi, T. M.

    1981-11-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  7. International market assessment of stand-alone photovoltaic power systems for cottage industry applications

    NASA Technical Reports Server (NTRS)

    Philippi, T. M.

    1981-01-01

    The final result of an international assessment of the market for stand-alone photovoltaic systems in cottage industry applications is reported. Nonindustrialized countries without centrally planned economies were considered. Cottage industries were defined as small rural manufacturers, employing less than 50 people, producing consumer and simple products. The data to support this analysis were obtained from secondary and expert sources in the U.S. and in-country field investigations of the Philippines and Mexico. The near-term market for photovoltaics for rural cottage industry applications appears to be limited to demonstration projects and pilot programs, based on an in-depth study of the nature of cottage industry, its role in the rural economy, the electric energy requirements of cottage industry, and a financial analysis of stand-alone photovoltaic systems as compared to their most viable competitor, diesel driven generators. Photovoltaics are shown to be a better long-term option only for very low power requirements. Some of these uses would include clay mixers, grinders, centrifuges, lathes, power saws and lighting of a workshop.

  8. Description of photovoltaic village power systems in the United States and Africa

    NASA Technical Reports Server (NTRS)

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

    1979-01-01

    The paper describes the designs, hardware, and installations of NASA photovoltaic power systems in the village of Schuchuli in Arizona and Tangaye in Upper Volta, Africa. The projects were designed to demonstrate that current photovoltaic system technology can provide electrical power for domestic services for small, remote communities. The Schuchuli system has a 3.5 kW peak solar array which provides power for water pumping, a refrigerator for each family, lights, and community washing and sewing machines. The 1.8 kW Tangaye system provides power for pumping, flour milling, and lights in the milling building. Both are stand-alone systems operated by local personnel, and they are monitored by NASA to measure design adequacy and refine future designs.

  9. A New Approach to Design of an optimized Grid Tied Smart Solar Photovoltaic (PV) System

    NASA Astrophysics Data System (ADS)

    Farhad, M. Mehedi; Ali, M. Mohammad; Iqbal, M. Asif; Islam, N. Nahar; Ashraf, N.

    2012-11-01

    Energy is the key element for the economical development of a country. With the increasing concern about the global demand for Renewable Energy (RE) energy, it is very much important to reduce the cost of the whole solar photovoltaic (PV) system. Still now most of the solar photovoltaic (PV) system is highly expensive. In this paper we have shown that grid tied solar system can be developed by omitting the energy storage device like large capacity battery bank. It will not only reduce the internallosses for charging and discharging of battery bank but also at the same time a large amount of cost of the battery will be reduced. So, the system maintenance cost will be reduced also. We have proposed a new approach to design a photovoltaic (PV) solar power system which can be operated by feeding the solar power to the national grid along with the residential load. Again if there is an extra power demand for residential load along with the solar power then this system can also provide an opportunity to consume the power from the national grid. The total system is controlled with the help of some the sensors and a microcontroller. As a whole a significant reduction in the system costs and efficient system performance can be realized.

  10. Design of a holographic micro-scale spectrum-splitting photovoltaic system

    NASA Astrophysics Data System (ADS)

    Wu, Yuechen; Vorndran, Shelby; Ayala Pelaez, Silvana; Russo, Juan M.; Kostuk, Raymond K.

    2015-09-01

    Micro-scale PV technology combines the high conversion efficiency of concentrated photovoltaics (CPV) with the low costs and the simple form of flat panel PV. Some of the benefits of micro-scale PV include: reduced semiconductor material usage; improved heat rejection capacity; and more versatile PV cell interconnect configurations. Spectrumsplitting is also a beneficial technique to increase the efficiency and reduce the cost of photovoltaic systems. It spatially separates the incident solar spectrum into spectral components and directs them to PV cells with matching bandgaps. This approach avoids the current and lattice matching problems that exist in tandem multi-junction systems. In this paper, we applied the ideas of spectrum-splitting in a micro-scale PV system, and demonstrated a holographic micro-scale spectrum-splitting photovoltaic system. This system consists of a volume transmission hologram in combination with a micro-lens array. An analysis methodology was developed to design the system and determine the performance of the resulting system. The spatial characteristics of the dispersed spectrum, the overall system conversion efficiency, and the improvement over best bandgap will be discussed.

  11. Advanced Docking Berthing System Update

    NASA Technical Reports Server (NTRS)

    Lewis, James

    2006-01-01

    In FY05 the Exploration Systems Technology Maturation Program selected the JSC advanced mating systems development to continue as an in-house project. In FY06, as a result of ESAS Study (60 Day Study) the CEV Project (within the Constellation Program) has chosen to continue the project as a GFE Flight Hardware development effort. New requirement for CEV to travel and dock with the ISS in 2011/12 in support of retiring the Shuttle and reducing the gap of time where US does not have any US based crew launch capability. As before, long-duration compatible seal-on-seal technology (seal-on-seal to support androgynous interface) has been identified as a risk mitigation item.

  12. Experimental Performance Investigation of Photovoltaic/Thermal (PV-T) System

    NASA Astrophysics Data System (ADS)

    Ozgoren, M.; Aksoy, M. H.; Bakir, C.; Dogan, S.

    2013-04-01

    Photovoltaic solar cells convert light energy from the sun into electricity. Photovoltaic cells are produced by semi-conducting materials to convert the energy into electricity and during this process heat is absorbed by the solar radiation. This heat causes a loss of electricity generation efficiencies.In this study, an experimental setup was designed and established to test two separate photovoltaic panel systems with alone PV and with water cooling system PV/T to examine the heat effect on PV systems. The absorbed heat energy behind the photovoltaic cell's surface in insulated ambient was removed by means of a water cooling system and the tests for both systems were simultaneously performed along the July 2011. It is found that without active water cooling, the temperature of the PV module was higher during day time and solar cells could only achieve around 8% conversion efficiency. On the other hand, when the PV module was operated with active water cooling condition, the temperature dropped significantly, leading to an increase in the efficiency of solarcells as much as 13.6%. Gained from absorbed solar heat and maximum thermal conversion efficiencies of the system are determined as 49% and 51% for two different mass flow rates. It is observed that water flow rate is effective on the increasing the conversion efficiency as well as absorption and transitionrates of cover glass in PV/T (PV-Thermal) collector, the insulation material and cell efficiency. As a conclusion, the conversion efficiency of the PV system with water cooling might be improved on average about 10%. Therefore, it is recommended that PV system should be designed with most efficient type cooling system to enhance the efficiency and to decrease the payback period.

  13. Integration of plug-in hybrid electric vehicles (PHEV) with grid connected residential photovoltaic energy systems

    NASA Astrophysics Data System (ADS)

    Nagarajan, Adarsh; Shireen, Wajiha

    2013-06-01

    This paper proposes an approach for integrating Plug-In Hybrid Electric Vehicles (PHEV) to an existing residential photovoltaic system, to control and optimize the power consumption of residential load. Control involves determining the source from which residential load will be catered, where as optimization of power flow reduces the stress on the grid. The system built to achieve the goal is a combination of the existing residential photovoltaic system, PHEV, Power Conditioning Unit (PCU), and a controller. The PCU involves two DC-DC Boost Converters and an inverter. This paper emphasizes on developing the controller logic and its implementation in order to accommodate the flexibility and benefits of the proposed integrated system. The proposed controller logic has been simulated using MATLAB SIMULINK and further implemented using Digital Signal Processor (DSP) microcontroller, TMS320F28035, from Texas Instruments

  14. Simple economic evaluation and applications experiments for photovoltaic systems for remote sites

    SciTech Connect

    Rios, M. Jr.

    1980-01-01

    A simple evaluation of the cost effectiveness of photovoltaic systems is presented. The evaluation is based on a calculation of breakeven costs of photovoltaics (PV) arrays with the levelized costs of two alternative energy sources (1) extension of the utility grid and (2) diesel generators. A selected number of PV applications experiments that are in progress in remote areas of the US are summarized. These applications experiments range from a 23 watt insect survey trap to a 100 kW PV system for a national park complex. It is concluded that PV systems for remote areas are now cost effective in remote small applications with commercially available technology and will be cost competitive for intermediate scale systems (approx. 10 kW) in the 1980s if the DOE 1986 Commercial Readiness Goals are achieved.

  15. Design and fabrication of a rectenna system to be coupled to photovoltaic solar cells

    NASA Astrophysics Data System (ADS)

    Mossavat, Mazda

    Inkjet-printed metamaterials and nanotechnology enabled flexible antennas fabricated on glass or polyester substrates help in further absorption of transmitted radiation through photovoltaic solar cells. Using metamaterials processed by inkjet printing and diffusing it, for a rectenna system coupled with photovoltaic solar cells, as rectifying antenna, an antenna in system in tandem is created. Metamaterials are artificial materials engineered to have properties that may not be found in nature (negative refractive index). When used in an antenna, they increase gain. For efficient solar cell use, nanophotonics on the incident surface or metamaterials under it as a rectenna, can enhance voltage gain in cloudy or rainy condition, which in turn increases the overall efficiency and reduces the amount of material required, thereby cutting costs. Photovoltaic is a field of technology and research related to practical application of photovoltaic cells in producing electricity from light. Cells are described as photovoltaic cells when the light source is not necessarily sunlight but can be lamplight, artificial light, or any other source used for detecting light or other electromagnetic radiation at different light intensity and producing voltage. These can be, for example, infrared detectors, or detectors for measurement of light intensity. Conventional solar cell films are typically manufactured using expensive and slow manufacturing methods, which rely on high-temperature fabrication and finicky `vacuum deposition' processes for depositing solar materials onto substrates (III-V elements). The resultant products are simply too thick to allow for transparency. An important consideration in the development of a commercially viable solar powered cell is the glass substrate. The learning process and skills involved in developing the antenna below a solar cell is a great experience in theory and practice. My main effort will be to design and check performance of different

  16. 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.

  17. 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.

  18. Optimum Concentration Ratio Analysis Using Dynamic Thermal Model for Concentrated Photovoltaic System

    DTIC Science & Technology

    2012-03-22

    solar cells , the quantum efficiency β approaches unity for all wavelengths with energies greater than the...different semiconductor material solar cells , such as GaAs , InGaP, CdTe, and other high- efficiency cell materials to investigate the thermal properties...photovoltaic conversion, and CSP systems represent the highest - efficiency solar energy systems currently on the market [8]. The increased solar

  19. Dynamic Model and Control of a Photovoltaic Generation System using Energetic Macroscopic Representation

    NASA Astrophysics Data System (ADS)

    Solano, Javier; Duarte, José; Vargas, Erwin; Cabrera, Jhon; Jácome, Andrés; Botero, Mónica; Rey, Juan

    2016-10-01

    This paper addresses the Energetic Macroscopic Representation EMR, the modelling and the control of photovoltaic panel PVP generation systems for simulation purposes. The model of the PVP considers the variations on irradiance and temperature. A maximum power point tracking MPPT algorithm is considered to control the power converter. A novel EMR is proposed to consider the dynamic model of the PVP with variations in the irradiance and the temperature. The EMR is evaluated through simulations of a PVP generation system.

  20. Utility-Interconnected Photovoltaic Systems: Evaluating the Rationale for the Utility-Accessible External Disconnect Switch

    SciTech Connect

    Coddington, M.; Margolis, R.M.; Aabakken, J.

    2008-01-01

    The utility-accessible alternating current (AC) external disconnect switch (EDS) for distributed generators, including photovoltaic (PV) systems, is a hardware feature that allows a utility?s employees to manually disconnect a customer-owned generator from the electricity grid. This paper examines the utility-accessible EDS debate in the context of utility-interactive PV systems for residential and small commercial installations. It also evaluates the rationale for EDS requirements.

  1. Evaluation of photovoltaic power generation system using spherical silicon solar cells and SiC-FET inverter

    NASA Astrophysics Data System (ADS)

    Matsumoto, Taisuke; Oku, Takeo; Hiramatsu, Koichi; Yasuda, Masashi; Shirahata, Yasuhiro; Shimono, Akio; Takeda, Yoshikazu; Murozono, Mikio

    2016-02-01

    A photovoltaic power generation system using spherical silicon (Si) solar cells and silicon carbide (SiC) field effect transistor (FET) inverter for photovoltaic applications was constructed and evaluated. The spherical Si solar cells were connected to the SiC-FET inverter and were used as a power source. Comparing the photovoltaic power generation system using an ordinary Si-FET inverter, direct current-alternating current conversion efficiencies of the SiC-FET inverter were improved due to reduction of power loss in the SiC-FET inverter.

  2. Advanced Space Surface Systems Operations

    NASA Technical Reports Server (NTRS)

    Huffaker, Zachary Lynn; Mueller, Robert P.

    2014-01-01

    The importance of advanced surface systems is becoming increasingly relevant in the modern age of space technology. Specifically, projects pursued by the Granular Mechanics and Regolith Operations (GMRO) Lab are unparalleled in the field of planetary resourcefulness. This internship opportunity involved projects that support properly utilizing natural resources from other celestial bodies. Beginning with the tele-robotic workstation, mechanical upgrades were necessary to consider for specific portions of the workstation consoles and successfully designed in concept. This would provide more means for innovation and creativity concerning advanced robotic operations. Project RASSOR is a regolith excavator robot whose primary objective is to mine, store, and dump regolith efficiently on other planetary surfaces. Mechanical adjustments were made to improve this robot's functionality, although there were some minor system changes left to perform before the opportunity ended. On the topic of excavator robots, the notes taken by the GMRO staff during the 2013 and 2014 Robotic Mining Competitions were effectively organized and analyzed for logistical purposes. Lessons learned from these annual competitions at Kennedy Space Center are greatly influential to the GMRO engineers and roboticists. Another project that GMRO staff support is Project Morpheus. Support for this project included successfully producing mathematical models of the eroded landing pad surface for the vertical testbed vehicle to predict a timeline for pad reparation. And finally, the last project this opportunity made contribution to was Project Neo, a project exterior to GMRO Lab projects, which focuses on rocket propulsion systems. Additions were successfully installed to the support structure of an original vertical testbed rocket engine, thus making progress towards futuristic test firings in which data will be analyzed by students affiliated with Rocket University. Each project will be explained in

  3. Design and construction evaluation of a photovoltaic DC LED lighting system

    NASA Astrophysics Data System (ADS)

    Bhamidipati, Jyotsna

    2008-08-01

    The market demand for commercialization of Photovoltaic (PV) systems depends a lot on the reliability, efficiency and performance of various components within the system. PV panels produce DC power when exposed to sunlight, and an inverter converts this to AC power in a typical solar powered building. Though, PV lighting has existed for a long time it hasn't been very effective, as incandescent light sources were commonly used which are inefficient. Today fluorescent fixtures are mostly used with PV's due to its high efficacy. Light-emitting diodes present a new vision to energy efficiency in lighting design with their low energy consumption. Current research predicts improved efficiencies of LED light fixtures and their commercial use is a few years away. LEDs which operate on DC voltages when coupled with photovoltaics can be a simple PV lighting application and a sustainable solution with potential for payback. This research evaluates the design and construction of a photovoltaic DC LED lighting system for a solar house at Pennsylvania State University. A detailed cost and payback analysis of a PV DC LED lighting system is presented in this research. PV output simulations for the solar house are presented. Results presented in this research indicate that the Solid state lighting market is evolving rapidly and that LED's are a choice in stand-alone photovoltaic DC lighting systems. The efficiency and the cost-effectiveness of such systems would however improve in the coming years with research and development now focused on PV systems and on Solid state lighting technologies.

  4. Optimal Design of MPPT Controllers for Grid Connected Photovoltaic Array System

    NASA Astrophysics Data System (ADS)

    Ebrahim, M. A.; AbdelHadi, H. A.; Mahmoud, H. M.; Saied, E. M.; Salama, M. M.

    2016-10-01

    Integrating photovoltaic (PV) plants into electric power system exhibits challenges to power system dynamic performance. These challenges stem primarily from the natural characteristics of PV plants, which differ in some respects from the conventional plants. The most significant challenge is how to extract and regulate the maximum power from the sun. This paper presents the optimal design for the most commonly used Maximum Power Point Tracking (MPPT) techniques based on Proportional Integral tuned by Particle Swarm Optimization (PI-PSO). These suggested techniques are, (1) the incremental conductance, (2) perturb and observe, (3) fractional short circuit current and (4) fractional open circuit voltage techniques. This research work provides a comprehensive comparative study with the energy availability ratio from photovoltaic panels. The simulation results proved that the proposed controllers have an impressive tracking response. The system dynamic performance improved greatly using the proposed controllers.

  5. Efficiency optimization of a photovoltaic water pumping system for irrigation in Ouargla, Algeria

    NASA Astrophysics Data System (ADS)

    Louazene, M. L.; Garcia, M. C. Alonso; Korichi, D.

    2017-02-01

    This work is technical study to contribute to the optimization of pumping systems powered by solar energy (clean) and used in the field of agriculture. To achieve our goals, we studied the techniques that must be entered on a photovoltaic system for maximum energy from solar panels. Our scientific contribution in this research is the realization of an efficient photovoltaic pumping system for irrigation needs. To achieve this and extract maximum power from the PV generator, two axes have been optimized: 1. Increase in the uptake of solar radiation by choice an optimum tilt angle of the solar panels, and 2. it is necessary to add an adaptation device, MPPT controller with a DC-DC converter, between the source and the load.

  6. Building America Best Practices Series, Volume 6: High-Performance Home Technologies: Solar Thermal & Photovoltaic Systems

    SciTech Connect

    Baechler, Michael C.; Gilbride, Theresa L.; Ruiz, Kathleen A.; Steward, Heidi E.; Love, Pat M.

    2007-06-04

    This guide is was written by PNNL for the US Department of Energy's Building America program to provide information for residential production builders interested in building near zero energy homes. The guide provides indepth descriptions of various roof-top photovoltaic power generating systems for homes. The guide also provides extensive information on various designs of solar thermal water heating systems for homes. The guide also provides construction company owners and managers with an understanding of how solar technologies can be added to their homes in a way that is cost effective, practical, and marketable. Twelve case studies provide examples of production builders across the United States who are building energy-efficient homes with photovoltaic or solar water heating systems.

  7. Fabrication of High Contrast Gratings for the Spectrum Splitting Dispersive Element in a Concentrated Photovoltaic System.

    PubMed

    Yao, Yuhan; Liu, He; Wu, Wei

    2015-07-18

    High contrast gratings are designed and fabricated and its application is proposed in a parallel spectrum splitting dispersive element that can improve the solar conversion efficiency of a concentrated photovoltaic system. The proposed system will also lower the solar cell cost in the concentrated photovoltaic system by replacing the expensive tandem solar cells with the cost-effective single junction solar cells. The structures and the parameters of high contrast gratings for the dispersive elements were numerically optimized. The large-area fabrication of high contrast gratings was experimentally demonstrated using nanoimprint lithography and dry etching. The quality of grating material and the performance of the fabricated device were both experimentally characterized. By analyzing the measurement results, the possible side effects from the fabrication processes are discussed and several methods that have the potential to improve the fabrication processes are proposed, which can help to increase the optical efficiency of the fabricated devices.

  8. A 10kW photovoltaic/hybrid system for Pinnacles National Monument

    SciTech Connect

    Ball, T.J.; DeNio, D.

    1997-12-31

    Visitors to the Chaparral area of the Pinnacles National Monument now can enjoy this beautiful section of the park without the constant drone of diesel generators, thanks to a recently installed photovoltaic/hybrid system. Electrical power had been supplied by two 100 KW diesel generators operating 24 hours per day. The diesels were running lightly loaded resulting in poor efficiency and high operating cost. Applied Power Corporation under contract with the National Park Service designed and supplied a 10 KW photovoltaic array, 200 KW hr battery bank and 24 KW of inverters to power the maintenance facility, visitor center and ranger residences. A new 20 KW propane generator was installed to provide supplemental power, totally eliminating the storage and transport of diesel fuel at this site. The Pinnacles PV/Hybrid system was brought on line in early 1996 and the park is now benefiting from the cost savings associated with the system.

  9. An analysis of photovoltaic irrigation system for olive orchards in Greece

    NASA Astrophysics Data System (ADS)

    Taousanidis, N.; Gavros, K.

    2016-11-01

    Olive tree cultivation is of major importance in Greece. It has been proved that irrigation of olive orchards increases their production. The classic method followed is diesel pump irrigation. Since Greece favours high insolation the alternative of photovoltaic pumping is proposed. A case study for an olive orchard in Crete is studied with the two alternatives. The photovoltaic pumping system is a direct pumping system as olive trees tolerate even deficit irrigation and storage tank increases the cost. A comparison using the Life Cycle Costing method is proposed. Considerations about climate and economic conditions are taken into account and the study concludes with the profound advantage of the renewable system over the conventional one in strict economic terms.

  10. An Intelligent Control for the Distributed Flexible Network Photovoltaic System using Autonomous Control and Agent

    NASA Astrophysics Data System (ADS)

    Park, Sangsoo; Miura, Yushi; Ise, Toshifumi

    This paper proposes an intelligent control for the distributed flexible network photovoltaic system using autonomous control and agent. The distributed flexible network photovoltaic system is composed of a secondary battery bank and a number of subsystems which have a solar array, a dc/dc converter and a load. The control mode of dc/dc converter can be selected based on local information by autonomous control. However, if only autonomous control using local information is applied, there are some problems associated with several cases such as voltage drop on long power lines. To overcome these problems, the authors propose introducing agents to improve control characteristics. The autonomous control with agents is called as intelligent control in this paper. The intelligent control scheme that employs the communication between agents is applied for the model system and proved with simulation using PSCAD/EMTDC.

  11. OPTIMIZATION OF ADVANCED FILTER SYSTEMS

    SciTech Connect

    R.A. Newby; M.A. Alvin; G.J. Bruck; T.E. Lippert; E.E. Smeltzer; M.E. Stampahar

    2002-06-30

    Two advanced, hot gas, barrier filter system concepts have been proposed by the Siemens Westinghouse Power Corporation to improve the reliability and availability of barrier filter systems in applications such as PFBC and IGCC power generation. The two hot gas, barrier filter system concepts, the inverted candle filter system and the sheet filter system, were the focus of bench-scale testing, data evaluations, and commercial cost evaluations to assess their feasibility as viable barrier filter systems. The program results show that the inverted candle filter system has high potential to be a highly reliable, commercially successful, hot gas, barrier filter system. Some types of thin-walled, standard candle filter elements can be used directly as inverted candle filter elements, and the development of a new type of filter element is not a requirement of this technology. Six types of inverted candle filter elements were procured and assessed in the program in cold flow and high-temperature test campaigns. The thin-walled McDermott 610 CFCC inverted candle filter elements, and the thin-walled Pall iron aluminide inverted candle filter elements are the best candidates for demonstration of the technology. Although the capital cost of the inverted candle filter system is estimated to range from about 0 to 15% greater than the capital cost of the standard candle filter system, the operating cost and life-cycle cost of the inverted candle filter system is expected to be superior to that of the standard candle filter system. Improved hot gas, barrier filter system availability will result in improved overall power plant economics. The inverted candle filter system is recommended for continued development through larger-scale testing in a coal-fueled test facility, and inverted candle containment equipment has been fabricated and shipped to a gasifier development site for potential future testing. Two types of sheet filter elements were procured and assessed in the program

  12. 205 kW Photovoltaic (PV) System Installed on the U.S. Department of Energy's Forrestal Building

    SciTech Connect

    2009-01-18

    Fact sheet on the installation of a photovoltaic system providing renewable energy for the U.S. Department of Energy and providing leadership for meeting Federal goals in the use of renewable energy technologies.

  13. Simplified design guide for estimating photovoltaic flat array and system performance

    SciTech Connect

    Evans, D.L.; Facinelli, W.A.; Koehler, L.P.

    1981-03-01

    Simplified, non-computer based methods are presented for predicting photovoltaic array and system performance. The array performance prediction methods are useful for calculating the potential output of passively cooled, flat, south facing max-power tracked arrays. A solar/weather data base for 97 different US and US affiliated stations is provided to aid in these calculations. Also, performance estimates can be made for photovoltaic systems (array, battery, power conditioner) that are backed-up by non-solar reserves capable of meeting the load when the solar system cannot. Such estimates can be made for a total of 41 different sinusoidal, unimodal, and bimodal diurnal load profiles from appropriate graphs included. These allow easy determination of the fraction of the load met by the solar photovoltaic system as a function of array size and (dedicated) battery storage capacity. These performance graphs may also be used for systems without battery storage. Use of array manufacturer's specification sheet data is discussed. Step-by-step procedures, along with suggested worksheets, are provided for carrying out the necessary calculations.

  14. PHOTO: A computer simulation program for photovoltaic and hybrid energy systems. Document and user's guide

    NASA Astrophysics Data System (ADS)

    Manninen, L. M.; Lund, P. D.; Virkkula, A.

    1990-11-01

    The version 3.0 is described of the program package PHOTO for the simulation and sizing of hybrid power systems (photovoltaic and wind power plants) on IBM PC, XT, AT, PS/2 and compatibles. The minimum memory requirement is 260 kB. Graphical output is created with HALO'88 graphics subroutine library. In the simulation model, special attention is given to the battery storage unit. A backup generator can also be included in the system configuration. The dynamic method developed uses accurate system component models accounting for component interactions and losses in e.g. wiring and diodes. The photovoltaic array can operate in a maximum power mode or in a clamped voltage mode together with the other subsystems. Various control strategies can also be considered. Individual subsystem models were verified against real measurements. Illustrative simulation example is also discussed. The presented model can be used to simulate various system configurations accurately and evaluate system performance, such as energy flows and power losses in photovoltaic array, wind generator, backup generator, wiring, diodes, maximum power point tracking device, inverter and battery. Energy cost is also an important consideration.

  15. Solar Powered Aircraft, Photovoltaic Array/Battery System Tabletop Demonstration: Design and Operation Manual

    NASA Technical Reports Server (NTRS)

    Colozza, Anthony J.; Scheiman, David A.; Bailey, Sheila (Technical Monitor)

    2000-01-01

    A system was constructed to demonstrate the power system operation of a solar powered aircraft. The system consists of a photovoltaic (PV) array, a charge controller, a battery, an electric motor and propeller. The system collects energy from the PV array and either utilizes this energy to operate an electric motor or stores it in a rechargeable battery for future use. The system has a control panel which displays the output of the array and battery as well as the total current going to the electric motor. The control panel also has a means for adjusting the output to the motor to control its speed. The entire system is regulated around 12 VDC.

  16. Design, development and deployment of public service photovoltaic power/load systems for the Gabonese Republic

    NASA Technical Reports Server (NTRS)

    Kaszeta, William J.

    1987-01-01

    Five different types of public service photovoltaic power/load systems installed in the Gabonese Republic are discussed. The village settings, the systems, performance results and some problems encountered are described. Most of the systems performed well, but some of the systems had problems due to failure of components or installation errors. The project was reasonably successful in collecting and reporting data for system performance evaluation that will be useful for guiding officials and system designers involved in village power applications in developing countries.

  17. Advanced integrated solvent extraction systems

    SciTech Connect

    Horwitz, E.P.; Dietz, M.L.; Leonard, R.A.

    1997-10-01

    Advanced integrated solvent extraction systems are a series of novel solvent extraction (SX) processes that will remove and recover all of the major radioisotopes from acidic-dissolved sludge or other acidic high-level wastes. The major focus of this effort during the last 2 years has been the development of a combined cesium-strontium extraction/recovery process, the Combined CSEX-SREX Process. The Combined CSEX-SREX Process relies on a mixture of a strontium-selective macrocyclic polyether and a novel cesium-selective extractant based on dibenzo 18-crown-6. The process offers several potential advantages over possible alternatives in a chemical processing scheme for high-level waste treatment. First, if the process is applied as the first step in chemical pretreatment, the radiation level for all subsequent processing steps (e.g., transuranic extraction/recovery, or TRUEX) will be significantly reduced. Thus, less costly shielding would be required. The second advantage of the Combined CSEX-SREX Process is that the recovered Cs-Sr fraction is non-transuranic, and therefore will decay to low-level waste after only a few hundred years. Finally, combining individual processes into a single process will reduce the amount of equipment required to pretreat the waste and therefore reduce the size and cost of the waste processing facility. In an ongoing collaboration with Lockheed Martin Idaho Technology Company (LMITCO), the authors have successfully tested various segments of the Advanced Integrated Solvent Extraction Systems. Eichrom Industries, Inc. (Darien, IL) synthesizes and markets the Sr extractant and can supply the Cs extractant on a limited basis. Plans are under way to perform a test of the Combined CSEX-SREX Process with real waste at LMITCO in the near future.

  18. Lead-free Organic-Inorganic Hybrid Perovskites for Photovoltaic Applications: Recent Advances and Perspectives.

    PubMed

    Shi, Zejiao; Guo, Jia; Chen, Yonghua; Li, Qi; Pan, Yufeng; Zhang, Haijuan; Xia, Yingdong; Huang, Wei

    2017-02-03

    Organic-inorganic hybrid halide perovskites (e.g., MAPbI3 ) have recently emerged as novel active materials for photovoltaic applications with power conversion efficiency over 22%. Conventional perovskite solar cells (PSCs); however, suffer the issue that lead is toxic to the environment and organisms for a long time and is hard to excrete from the body. Therefore, it is imperative to find environmentally-friendly metal ions to replace lead for the further development of PSCs. Previous work has demonstrated that Sn, Ge, Cu, Bi, and Sb ions could be used as alternative ions in perovskite configurations to form a new environmentally-friendly lead-free perovskite structure. Here, we review recent progress on lead-free PSCs in terms of the theoretical insight and experimental explorations of the crystal structure of lead-free perovskite, thin film deposition, and device performance. We also discuss the importance of obtaining further understanding of the fundamental properties of lead-free hybrid perovskites, especially those related to photophysics.

  19. Westinghouse Advanced Particle Filter System

    SciTech Connect

    Lippert, T.E.; Bruck, G.J.; Sanjana, Z.N.; Newby, R.A.; Bachovchin, D.M.

    1996-12-31

    Integrated Gasification Combined Cycles (IGCC) and Pressurized Fluidized Bed Combustion (PFBC) are being developed and demonstrated for commercial, power generation application. Hot gas particulate filters are key components for the successful implementation of IGCC and PFBC in power generation gas turbine cycles. The objective of this work is to develop and qualify through analysis and testing a practical hot gas ceramic barrier filter system that meets the performance and operational requirements of PFBC and IGCC systems. This paper reports on the development and status of testing of the Westinghouse Advanced Hot Gas Particle Filter (W-APF) including: W-APF integrated operation with the American Electric Power, 70 MW PFBC clean coal facility--approximately 6000 test hours completed; approximately 2500 hours of testing at the Hans Ahlstrom 10 MW PCFB facility located in Karhula, Finland; over 700 hours of operation at the Foster Wheeler 2 MW 2nd generation PFBC facility located in Livingston, New Jersey; status of Westinghouse HGF supply for the DOE Southern Company Services Power System Development Facility (PSDF) located in Wilsonville, Alabama; the status of the Westinghouse development and testing of HGF`s for Biomass Power Generation; and the status of the design and supply of the HGF unit for the 95 MW Pinon Pine IGCC Clean Coal Demonstration.

  20. Photovoltaic power generation for air-conditioning system based on predictive control

    SciTech Connect

    Kim, S.; Choi, J.; Park, G.; Yoo Jiyoon

    1995-12-31

    In this paper an auxiliary power supply scheme using photovoltaic power generation for air-conditioning system and its novel control strategy are proposed. The proposed auxiliary power supply system employs a boost converter, a bidirectional power converter and photovoltaic arrays. The boost converter controlled by a predictive control strategy provides maximum power track (MPT) state on the photovoltaic (PV) arrays as well as power generation facility function on the ac utility grid. Furthermore the bidirectional power converter controls the power flow balance between the loads and two different power sources according to the condition of the load power and the supplied power from photovoltaic arrays. It is shown that the maximum power tracking of the PV arrays, the unit power factor of ac utility grid and the descent input dc voltage regulation of the air-conditioning system are achieved by the proposed predictive control strategy. The proposed switching strategy for the boost converter and the bidirectional power converter are based on the predictive control with ac line current and output voltage of the PV arrays. The bidirectional power converter is suitably modulation controlled to rectify the ac source during the power shortage under the poor power generation of PV arrays or over load conditions of air conditioner. During the opposite state, the bidirectional power converter is gated to function as a regeneration inverter. Controller design procedure for the proposed approach to achieve near sinusoidal input currents under the inverter mode and the rectifier mode is detailed. Simulation results on a laboratory prototype system are discussed. Experimental results from the laboratory prototype system will be presented in the near future.

  1. System for characterizing semiconductor materials and photovoltaic device

    DOEpatents

    Sopori, B.L.

    1996-12-03

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline material in a manner that distinguishes dislocation pits from grain boundaries includes a first laser of a first wavelength for illuminating a wide spot on the surface of the material, a second laser of a second relatively shorter wavelength for illuminating a relatively narrower spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate raster mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. A reflectance measurement of the piece of material is obtained by adding together the signals from the optical detection devices. In the case where the piece of material includes a photovoltaic device, the current induced in the device by the illuminating light can be measured with a current sensing amplifier after the light integrating sphere is moved away from the device. 22 figs.

  2. System for characterizing semiconductor materials and photovoltaic device

    DOEpatents

    Sopori, Bhushan L.

    1996-01-01

    Apparatus for detecting and mapping defects in the surfaces of polycrystalline material in a manner that distinguishes dislocation pits from grain boundaries includes a first laser of a first wavelength for illuminating a wide spot on the surface of the material, a second laser of a second relatively shorter wavelength for illuminating a relatively narrower spot on the surface of the material, a light integrating sphere with apertures for capturing light scattered by etched dislocation pits in an intermediate range away from specular reflection while allowing light scattered by etched grain boundaries in a near range from specular reflection to pass through, and optical detection devices for detecting and measuring intensities of the respective intermediate scattered light and near specular scattered light. A center blocking aperture or filter can be used to screen out specular reflected light, which would be reflected by nondefect portions of the polycrystalline material surface. An X-Y translation stage for mounting the polycrystalline material and signal processing and computer equipment accommodate raster mapping, recording, and displaying of respective dislocation and grain boundary defect densities. A special etch procedure is included, which prepares the polycrystalline material surface to produce distinguishable intermediate and near specular light scattering in patterns that have statistical relevance to the dislocation and grain boundary defect densities. A reflectance measurement of the piece of material is obtained by adding together the signals from the optical detection devices. In the case where the piece of material includes a photovoltaic device, the current induced in the device by the illuminating light can be measured with a current sensing amplifier after the light integrating sphere is moved away from the device.

  3. A solar photovoltaic system with ideal efficiency close to the theoretical limit.

    PubMed

    Zhao, Yuan; Sheng, Ming-Yu; Zhou, Wei-Xi; Shen, Yan; Hu, Er-Tao; Chen, Jian-Bo; Xu, Min; Zheng, Yu-Xiang; Lee, Young-Pak; Lynch, David W; Chen, Liang-Yao

    2012-01-02

    In order to overcome some physical limits, a solar system consisting of five single-junction photocells with four optical filters is studied. The four filters divide the solar spectrum into five spectral regions. Each single-junction photocell with the highest photovoltaic efficiency in a narrower spectral region is chosen to optimally fit into the bandwidth of that spectral region. Under the condition of solar radiation ranging from 2.4 SUN to 3.8 SUN (AM1.5G), the measured peak efficiency under 2.8 SUN radiation reaches about 35.6%, corresponding to an ideal efficiency of about 42.7%, achieved for the photocell system with a perfect diode structure. Based on the detailed-balance model, the calculated theoretical efficiency limit for the system consisting of 5 single-junction photocells can be about 52.9% under 2.8 SUN (AM1.5G) radiation, implying that the ratio of the highest photovoltaic conversion efficiency for the ideal photodiode structure to the theoretical efficiency limit can reach about 80.7%. The results of this work will provide a way to further enhance the photovoltaic conversion efficiency for solar cell systems in future applications.

  4. Energy analysis of facade-integrated photovoltaic systems applied to UAE commercial buildings

    SciTech Connect

    Radhi, Hassan

    2010-12-15

    Developments in the design and manufacture of photovoltaic cells have recently been a growing concern in the UAE. At present, the embodied energy pay-back time (EPBT) is the criterion used for comparing the viability of such technology against other forms. However, the impact of PV technology on the thermal performance of buildings is not considered at the time of EPBT estimation. If additional energy savings gained over the PV system life are also included, the total EPBT could be shorter. This paper explores the variation of the total energy of building integrated photovoltaic systems (BiPV) as a wall cladding system applied to the UAE commercial sector and shows that the ratio between PV output and saving in energy due to PV panels is within the range of 1:3-1:4. The result indicates that for the southern and western facades in the UAE, the embodied energy pay-back time for photovoltaic system is within the range of 12-13 years. When reductions in operational energy are considered, the pay-back time is reduced to 3.0-3.2 years. This study comes to the conclusion that the reduction in operational energy due to PV panels represents an important factor in the estimation of EPBT. (author)

  5. Optimization of a photovoltaic pumping system based on the optimal control theory

    SciTech Connect

    Betka, A.; Attali, A.

    2010-07-15

    This paper suggests how an optimal operation of a photovoltaic pumping system based on an induction motor driving a centrifugal pump can be realized. The optimization problem consists in maximizing the daily pumped water quantity via the optimization of the motor efficiency for every operation point. The proposed structure allows at the same time the minimization the machine losses, the field oriented control and the maximum power tracking of the photovoltaic array. This will be attained based on multi-input and multi-output optimal regulator theory. The effectiveness of the proposed algorithm is described by simulation and the obtained results are compared to those of a system working with a constant air gap flux. (author)

  6. Utility-Side Voltage and PQ Control with Inverter-based Photovoltaic Systems

    SciTech Connect

    Adhikari, Sarina; Xu, Yan; Li, Fangxing; Li, Huijuan; Kueck, John D; Snyder, Isabelle B; Barker, Thomas J.; Hite, Ronald

    2011-01-01

    Distributed energy resources (DER) are small generators located close to the load centers. The DERs that are integrated to the grid with the power electronic converter interfaces are capable of providing nonactive power in addition to active power. Hence, they are capable of regulating the voltages of the weak buses in the distribution systems. This paper discusses the voltage control capability of photovoltaic (PV) systems as compared to the traditional capacitor banks. The simulation results prove the effectiveness of dynamic voltage control capability of inverter-based PV. With the proper control algorithm, the active and nonactive power from the DERs like battery banks or solar photovoltaic can be controlled independently. This paper also presents the scenario of controlling the active and nonactive power from the PV array to track and supply the local load.

  7. User evaluation of photovoltaic-powered vaccine refrigerator/freezer systems

    NASA Technical Reports Server (NTRS)

    Ratajczak, Anthony F.

    1987-01-01

    The NASA Lewis Research Center has concluded a project to develop and field test photovoltaic-powered refrigerator/freezers for vaccine storage in remote areas of developing countries. As a conclusion to this project, questionnaires were sent to the in-country administrators for each test site probing user acceptance of the systems and attitudes regarding procurement of additional systems. Responses indicate that the systems had a positive effect on the local communities, that they made a positive impression on the local health authorities, and that system cost and scarcity of funds are the major barriers to procurements of additional systems.

  8. Investigation of energy management strategies for photovoltaic systems - A predictive control algorithm

    NASA Technical Reports Server (NTRS)

    Cull, R. C.; Eltimsahy, A. H.

    1983-01-01

    The present investigation is concerned with the formulation of energy management strategies for stand-alone photovoltaic (PV) systems, taking into account a basic control algorithm for a possible predictive, (and adaptive) controller. The control system controls the flow of energy in the system according to the amount of energy available, and predicts the appropriate control set-points based on the energy (insolation) available by using an appropriate system model. Aspects of adaptation to the conditions of the system are also considered. Attention is given to a statistical analysis technique, the analysis inputs, the analysis procedure, and details regarding the basic control algorithm.

  9. Description and status of NASA-LeRC/DOE photovoltaic applications systems

    NASA Technical Reports Server (NTRS)

    Ratajczak, A. F.

    1978-01-01

    Designed, fabricated and installed were 16 geographically dispersed photovoltaic systems. These systems are powering a refrigerator, highway warning sign, forest lookout towers, remote weather stations, a water chiller at a visitor center, and insect survey traps. Each of these systems is described in terms of load requirements, solar array and battery size, and instrumentation and controls. Operational experience is described and present status is given for each system. The P/V power systems have proven to be highly reliable with almost no problems with modules and very few problems overall.

  10. User evaluation of photovoltaic-powered vaccine refrigerator/freezer systems

    NASA Astrophysics Data System (ADS)

    Ratajczak, Anthony F.

    1987-03-01

    The NASA Lewis Research Center has concluded a project to develop and field test photovoltaic-powered refrigerator/freezers for vaccine storage in remote areas of developing countries. As a conclusion to this project, questionnaires were sent to the in-country administrators for each test site probing user acceptance of the systems and attitudes regarding procurement of additional systems. Responses indicate that the systems had a positive effect on the local communities, that they made a positive impression on the local health authorities, and that system cost and scarcity of funds are the major barriers to procurements of additional systems.

  11. Performance advantages of two-axis tracking for large flat-plate photovoltaic energy systems

    SciTech Connect

    Gay, C.F.; Wilson, J.H.; Yerkes, J.W.

    1982-09-01

    Daily and annual energy-delivery performance is compared for large-scale fixed-array and two-axis tracking photovoltaic generating systems similar to the ASI Project at Lugo, California. Systems of equal peak-watt rating and systems of different sizes but equal annual energy output are compared in the Lugo setting. Site sensitivities are discussed. For the site studied, it is observed that a fixed-array system would use about 40% more modules than a two-axis tracking system, for equal annual energy.

  12. Performance advantages of two-axis tracking for large flat-plate photovoltaic energy systems

    NASA Astrophysics Data System (ADS)

    Gay, C. F.; Yerkes, J. W.; Wilson, J. H.

    Daily and annual energy-delivery performance is compared for large-scale fixed-array and two-axis tracking photovoltaic generating systems similar to the ASI Project at Lugo, CA. Systems of equal peak-watt rating and systems of different sizes but equal annual energy output are compared in the Lugo setting. Site sensitivities are discussed. For the site studied, it is observed that a fixed-array system would use about 40 percent more modules than a two-axis tracking system, for equal annual energy.

  13. Design, installation and operating experience of 20 photovoltaic medical refrigerator systems on four continents

    NASA Technical Reports Server (NTRS)

    Hein, G. F.

    1982-01-01

    The NASA Lewis Research Center in cooperation with the World Health Organization, U.S.A. I.D., the Pan American Health Organization and national government agencies in some developing countries sponsored the installation of twenty photovoltaic powered medical vaccine storage refrigerator-freezer (R/F) systems. The Solar Power Corporation was selected as the contractor to perform the design, development and installation of these twenty units. Solar Power's experiences are described herein.

  14. SUNRAYCE 95: Working safely with lead-acid batteries and photovoltaic power systems

    SciTech Connect

    DePhillips, M.P.; Moskowitz, P.D.; Fthenakis, V.M.

    1994-05-27

    This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.

  15. SUNRAYCE 1995: Working safely with lead-acid batteries and photovoltaic power systems

    NASA Astrophysics Data System (ADS)

    Dephillips, M. P.; Moskowitz, P. D.; Fthenakis, V. M.

    1994-05-01

    This document is a power system and battery safety handbook for participants in the SUNRAYCE 95 solar powered electric vehicle program. The topics of the handbook include batteries, photovoltaic modules, safety equipment needed for working with sulfuric acid electrolyte and batteries, battery transport, accident response, battery recharging and ventilation, electrical risks on-board vehicle, external electrical risks, electrical risk management strategies, and general maintenance including troubleshooting, hydrometer check and voltmeter check.

  16. Design of Photovoltaic Power System for a Precursor Mission for Human Exploration of Mars

    NASA Technical Reports Server (NTRS)

    Mcnatt, Jeremiah; Landis, Geoffrey; Fincannon, James

    2016-01-01

    This project analyzed the viability of a photovoltaic power source for technology demonstration mission to demonstrate Mars in-situ resource utilization (ISRU) to produce propellant for a future human mission, based on technology available within the next ten years. For this assessment, we performed a power-system design study for a scaled ISRU demonstrator lander on the Mars surface based on existing solar array technologies.

  17. Design and development of a laminated glass-plastic Fresnel lens for point focus photovoltaic systems

    SciTech Connect

    Matalon, L. A.

    1982-08-01

    The design and development of a laminated glass-plastic Fresnel lens for point focus photovoltaic systems use is described. The objective of this development was to examine the feasibility of producing lenses with a cost effectiveness superior to that of lenses made by casting of acrylic. The procedure used in executing this development, the method used in cost effectiveness evaluation, results obtained and recommendations for further work are presented.

  18. Design, installation and operating experience of 20 photovoltaic medical refrigerator systems on four continents

    NASA Astrophysics Data System (ADS)

    Hein, G. F.

    The NASA Lewis Research Center in cooperation with the World Health Organization, U.S.A. I.D., the Pan American Health Organization and national government agencies in some developing countries sponsored the installation of twenty photovoltaic powered medical vaccine storage refrigerator-freezer (R/F) systems. The Solar Power Corporation was selected as the contractor to perform the design, development and installation of these twenty units. Solar Power's experiences are described herein.

  19. Advanced information processing system: Local system services

    NASA Technical Reports Server (NTRS)

    Burkhardt, Laura; Alger, Linda; Whittredge, Roy; Stasiowski, Peter

    1989-01-01

    The Advanced Information Processing System (AIPS) is a multi-computer architecture composed of hardware and software building blocks that can be configured to meet a broad range of application requirements. The hardware building blocks are fault-tolerant, general-purpose computers, fault-and damage-tolerant networks (both computer and input/output), and interfaces between the networks and the computers. The software building blocks are the major software functions: local system services, input/output, system services, inter-computer system services, and the system manager. The foundation of the local system services is an operating system with the functions required for a traditional real-time multi-tasking computer, such as task scheduling, inter-task communication, memory management, interrupt handling, and time maintenance. Resting on this foundation are the redundancy management functions necessary in a redundant computer and the status reporting functions required for an operator interface. The functional requirements, functional design and detailed specifications for all the local system services are documented.

  20. Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

    NASA Astrophysics Data System (ADS)

    Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

    2011-01-01

    With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.