WorldWideScience

Sample records for european solar thermal

  1. European standards for thermal solar systems and components. The finals

    NARCIS (Netherlands)

    Drück, H.; Heidemann, W.; Müller, H.; Veenstra, A.

    2001-01-01

    In Europe standards for solar collectors, hot water stores and for complete thermal solar systems have been developed during the past six years. This year (2001) these European Standards were established and therefore replaced all corresponding national standards. In the new European standards basic

  2. estec2007 - 3rd European solar thermal energy conference. Proceedings

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2007-12-14

    The sessions of the 'estec2007 - 3{sup rd} European Solar Thermal Energy Conference held in Freiburg, Germany have the following titles: The solar thermal sector at a turning point; Cooling and Process Heat, Country reports Europe; Standards and Certification; Country reports outside Europe; Awareness raising and marketing; Domestic hot water and space heating; Domestic hot water and space heating; Quality Assurance and Solar Thermal Energy Service Companies; Collectors and other key technical issues; Policy - Financial incentives; Country Reports; Marketing and Awareness Raising; Quality Assurance Measures/Monistoring; Standards and Certification; Collectors; Domestic Hot Water and Space Heating; Industrial Process Heat; Storage; Solar Cooling. (AKF)

  3. Estec2003: European solar thermal energy conference. Proceedings; Estec2003: Europaeische Solarthermie-Konferenz. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    In December 2002 more than 40 solar thermal companies and associations joined forces in the European Solar Thermal Industry Federation (ESTIF), to strengthen support for this clean technology on the European level. ESTIF aims at building a close partnership between industry and public authorities in order to overcome the main barriers to growth. Over the last 6 months we have seen some positive developments, which we could build upon. Here are some examples: 1. Germany, the country with the largest demand for solar thermal technology, is back on track to repeat the growth rates we have witnessed in the 1990s. 2. The rules for the solar Keymark quality label were approved by CEN board in January 2003. 3. The city of Madrid became the first European capital to follow the example of Barcelona in requiring the use of solar thermal in new residential buildings. 4. The long awaited ''Sun in Action II - a solar thermal strategy for Europe was published last month. 5. Now, the first European Solar Thermal Energy Conference brings together decision makers from industry and politics to discuss the future of renewable heating and cooling in Europe. - Solar thermal has a great potential - 1.4 billion square meters in the 15 EU member states alone. 99% of this potential are still to be developed. ESTIF has made it its mission 'to achieve high priority and acceptance for solar thermal as a key element for sustainable heating and cooling in Europe and to work for the implementation, as soon as possible, of all steps necessary to realise the high potential of solar thermal'. With estec2003 we offer a platform to exchange information and opinions concerning how this goal can be achieved. The developments in different countries show that the use of solar thermal technologies does not depend on climatic conditions alone. (orig.)

  4. Advanced windows Information System (WIS): A uniform European tool to calculate the thermal and solar properties of windows

    NARCIS (Netherlands)

    Bakker, L.G.; Dijk, H.A.L. van

    1996-01-01

    WIS is a uniform, user friendly, PC-based, European software tool to determine the thermal and solar character-istics of window systems (glazing, frames, solar shading, etc.) and window components. WIS includes databases with component properties and routines for calculation of the thermal-optical

  5. Solar Thermal Energy Technology

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Pitsenbarger, J. [eds.

    1996-02-01

    Solar Thermal Energy Technology (PST) announces on a bimonthly basis the current worldwide research and development information that would expand the technology base required for the advancement of solar thermal systems as a significant energy resource.

  6. Concentrating solar thermal power.

    Science.gov (United States)

    Müller-Steinhagen, Hans

    2013-08-13

    In addition to wind and photovoltaic power, concentrating solar thermal power (CSP) will make a major contribution to electricity provision from renewable energies. Drawing on almost 30 years of operational experience in the multi-megawatt range, CSP is now a proven technology with a reliable cost and performance record. In conjunction with thermal energy storage, electricity can be provided according to demand. To date, solar thermal power plants with a total capacity of 1.3 GW are in operation worldwide, with an additional 2.3 GW under construction and 31.7 GW in advanced planning stage. Depending on the concentration factors, temperatures up to 1000°C can be reached to produce saturated or superheated steam for steam turbine cycles or compressed hot gas for gas turbine cycles. The heat rejected from these thermodynamic cycles can be used for sea water desalination, process heat and centralized provision of chilled water. While electricity generation from CSP plants is still more expensive than from wind turbines or photovoltaic panels, its independence from fluctuations and daily variation of wind speed and solar radiation provides it with a higher value. To become competitive with mid-load electricity from conventional power plants within the next 10-15 years, mass production of components, increased plant size and planning/operating experience will be accompanied by technological innovations. On 30 October 2009, a number of major industrial companies joined forces to establish the so-called DESERTEC Industry Initiative, which aims at providing by 2050 15 per cent of European electricity from renewable energy sources in North Africa, while at the same time securing energy, water, income and employment for this region. Solar thermal power plants are in the heart of this concept.

  7. Latest developments in the field of solar thermal standardisation

    OpenAIRE

    Fischer, S.; M. J. Carvalho; Kovacs, P.; Malenkovic, I.

    2011-01-01

    The European project QAiST-―Quality Assurance in Solar Thermal Heating and Cooling Technology‖ funded by the Intelligent Energy Europe program and by the participating countries, gathers 15 participating organizations including the European Solar Thermal Industry Federation ESTIF and major testing and research institutes in Europe. The objective of the project is to enhance the competitiveness of the European Solar thermal industry and further increase consumer confidence through improved ...

  8. Solar thermal conversion

    Science.gov (United States)

    Selcuk, M. K.

    1978-01-01

    A brief review of the fundamentals of the conversion of solar energy into mechanical work (or electricity via generators) is given. Both past and present work on several conversion concepts are discussed. Solar collectors, storage systems, energy transport, and various types of engines are examined. Ongoing work on novel concepts of collectors, energy storage and thermal energy conversion are outlined and projections for the future are described. Energy costs for various options are predicted and margins and limitations are discussed.

  9. Solar thermal financing guidebook

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.A.; Cole, R.J.; Brown, D.R.; Dirks, J.A.; Edelhertz, H.; Holmlund, I.; Malhotra, S.; Smith, S.A.; Sommers, P.; Willke, T.L.

    1983-05-01

    This guidebook contains information on alternative financing methods that could be used to develop solar thermal systems. The financing arrangements discussed include several lease alternatives, joint venture financing, R and D partnerships, industrial revenue bonds, and ordinary sales. In many situations, alternative financing arrangements can significantly enhance the economic attractiveness of solar thermal investments by providing a means to efficiently allocate elements of risk, return on investment, required capital investment, and tax benefits. A net present value approach is an appropriate method that can be used to investigate the economic attractiveness of alternative financing methods. Although other methods are applicable, the net present value approach has advantages of accounting for the time value of money, yielding a single valued solution to the financial analysis, focusing attention on the opportunity cost of capital, and being a commonly understood concept that is relatively simple to apply. A personal computer model for quickly assessing the present value of investments in solar thermal plants with alternative financing methods is presented in this guidebook. General types of financing arrangements that may be desirable for an individual can be chosen based on an assessment of his goals in investing in solar thermal systems and knowledge of the individual's tax situation. Once general financing arrangements have been selected, a screening analysis can quickly determine if the solar investment is worthy of detailed study.

  10. Solar Thermal Power.

    Science.gov (United States)

    McDaniels, David K.

    The different approaches to the generation of power from solar energy may be roughly divided into five categories: distributed collectors; central receivers; biomass; ocean thermal energy conversion; and photovoltaic devices. The first approach (distributed collectors) is the subject of this module. The material presented is designed to…

  11. Solar thermal technology

    Science.gov (United States)

    1988-09-01

    This annual report describes the accomplishments and progress of government-funded activities initiated, renewed, or completed during Fiscal Year (FY) 1987 (October 1, 1986, through September 30, 1987). It highlights the program tasks conducted by participating federal laboratories and by industrial, academic, or other research under a subcontract. The emphasis of the Solar Thermal Technology Program during the year was: (1) to perform research and development leading to the economic viability of two primary solar thermal concepts, central receiver and parabolic dish, and (2) to explore applications of national significance where the special attributes of concentrated sunlight are appropriate. The report includes three appendices that cover principal contacts and sources of additional information (Appendix A), acronyms and abbreviations (Appendix B), and a glossary of terms (Appendix C). A bibliography of relevant publications from Sandia National Laboratories and the Solar Energy Research Institute completes this annual report.

  12. Solar engineering of thermal processes

    CERN Document Server

    Duffie, John A

    2013-01-01

    The updated fourth edition of the ""bible"" of solar energy theory and applications Over several editions, Solar Engineering of Thermal Processes has become a classic solar engineering text and reference. This revised Fourth Edition offers current coverage of solar energy theory, systems design, and applications in different market sectors along with an emphasis on solar system design and analysis using simulations to help readers translate theory into practice. An important resource for students of solar engineering, solar energy, and alternative energy as well

  13. Solar Thermal Concept Evaluation

    Science.gov (United States)

    Hawk, Clark W.; Bonometti, Joseph A.

    1995-01-01

    Concentrated solar thermal energy can be utilized in a variety of high temperature applications for both terrestrial and space environments. In each application, knowledge of the collector and absorber's heat exchange interaction is required. To understand this coupled mechanism, various concentrator types and geometries, as well as, their relationship to the physical absorber mechanics were investigated. To conduct experimental tests various parts of a 5,000 watt, thermal concentrator, facility were made and evaluated. This was in anticipation at a larger NASA facility proposed for construction. Although much of the work centered on solar thermal propulsion for an upper stage (less than one pound thrust range), the information generated and the facility's capabilities are applicable to material processing, power generation and similar uses. The numerical calculations used to design the laboratory mirror and the procedure for evaluating other solar collectors are presented here. The mirror design is based on a hexagonal faceted system, which uses a spherical approximation to the parabolic surface. The work began with a few two dimensional estimates and continued with a full, three dimensional, numerical algorithm written in FORTRAN code. This was compared to a full geometry, ray trace program, BEAM 4, which optimizes the curvatures, based on purely optical considerations. Founded on numerical results, the characteristics of a faceted concentrator were construed. The numerical methodologies themselves were evaluated and categorized. As a result, the three-dimensional FORTRAN code was the method chosen to construct the mirrors, due to its overall accuracy and superior results to the ray trace program. This information is being used to fabricate and subsequently, laser map the actual mirror surfaces. Evaluation of concentrator mirrors, thermal applications and scaling the results of the 10 foot diameter mirror to a much larger concentrator, were studied. Evaluations

  14. Solar thermal power system

    Science.gov (United States)

    Bennett, Charles L.

    2010-06-15

    A solar thermal power generator includes an inclined elongated boiler tube positioned in the focus of a solar concentrator for generating steam from water. The boiler tube is connected at one end to receive water from a pressure vessel as well as connected at an opposite end to return steam back to the vessel in a fluidic circuit arrangement that stores energy in the form of heated water in the pressure vessel. An expander, condenser, and reservoir are also connected in series to respectively produce work using the steam passed either directly (above a water line in the vessel) or indirectly (below a water line in the vessel) through the pressure vessel, condense the expanded steam, and collect the condensed water. The reservoir also supplies the collected water back to the pressure vessel at the end of a diurnal cycle when the vessel is sufficiently depressurized, so that the system is reset to repeat the cycle the following day. The circuital arrangement of the boiler tube and the pressure vessel operates to dampen flow instabilities in the boiler tube, damp out the effects of solar transients, and provide thermal energy storage which enables time shifting of power generation to better align with the higher demand for energy during peak energy usage periods.

  15. ESMN / European Solar Physics Research Area

    NARCIS (Netherlands)

    Rutten, R.J.

    1999-01-01

    I briefly present the European Solar Magnetometry Network as a contemporary example of solar physics collaboration across European borders,and I place it in larger-scale context by discussing the past and future of Europe-wide solar physics organization.Solar physics from space is inherently

  16. Solar Thermal Energy; Energia Solar Termica

    Energy Technology Data Exchange (ETDEWEB)

    Perez-Martinez, M.; Cuesta-Santianes, M. J.; Cabrera Jimenez, J. A.

    2008-07-01

    Approximately, 50 % of worldwide primary energy consumption is done in the form of heat in applications with a temperature lower than 250 degree centigree (low-medium temperature heat). These data clearly demonstrate the great potential of solar thermal energy to substitute conventional fossil fuels, which are becoming more expensive and are responsible for global warming. Low-medium temperature solar thermal energy is mainly used to obtain domestic hot water and provide space heating. Active solar thermal systems are those related to the use of solar thermal collectors. This study is dealing with low temperature solar thermal applications, mainly focusing on active solar thermal systems. This kind of systems has been extensively growing worldwide during the last years. At the end of 2006, the collector capacity in operation worldwide equalled 127.8 GWth. The technology is considered to be already developed and actions should be aimed at favouring a greater market penetration: diffusion, financial support, regulations establishment, etc. China and USA are the leading countries with a technology based on evacuated tube collectors and unglazed collectors, respectively. The rest of the world markets are dominated by the flat glazed collectors technology. (Author) 15 refs.

  17. Concentrated solar thermal power - Now

    Energy Technology Data Exchange (ETDEWEB)

    Aringhoff, R.; Brakmann, G. [Solar Thermal Power Industry Association ESTIA, Avenue de la Fauconnerie 73, 1170 Brussels (Belgium); Geyer, M. [IEA SolarPACES Implementing Agreement, Avenida de la Paz 51, 04720 Aguadulce, Almeria (Spain); Teske, S. [Greenpeace International, Ottho Heldringstraat 5, 1066 AZ Amsterdam (Netherlands)

    2005-09-15

    This report demonstrates that there are no technical, economic or resource barriers to supplying 5% of the world's electricity needs from solar thermal power by 2040. It is written as practical blueprint to improve understanding of the solar thermal contribution to the world energy supply.

  18. Scattering Solar Thermal Concentrators

    Energy Technology Data Exchange (ETDEWEB)

    Giebink, Noel C. [Pennsylvania State Univ., State College, PA (United States)

    2015-01-31

    This program set out to explore a scattering-based approach to concentrate sunlight with the aim of improving collector field reliability and of eliminating wind loading and gross mechanical movement through the use of a stationary collection optic. The approach is based on scattering sunlight from the focal point of a fixed collection optic into the confined modes of a sliding planar waveguide, where it is transported to stationary tubular heat transfer elements located at the edges. Optical design for the first stage of solar concentration, which entails focusing sunlight within a plane over a wide range of incidence angles (>120 degree full field of view) at fixed tilt, led to the development of a new, folded-path collection optic that dramatically out-performs the current state-of-the-art in scattering concentration. Rigorous optical simulation and experimental testing of this collection optic have validated its performance. In the course of this work, we also identified an opportunity for concentrating photovoltaics involving the use of high efficiency microcells made in collaboration with partners at the University of Illinois. This opportunity exploited the same collection optic design as used for the scattering solar thermal concentrator and was therefore pursued in parallel. This system was experimentally demonstrated to achieve >200x optical concentration with >70% optical efficiency over a full day by tracking with <1 cm of lateral movement at fixed latitude tilt. The entire scattering concentrator waveguide optical system has been simulated, tested, and assembled at small scale to verify ray tracing models. These models were subsequently used to predict the full system optical performance at larger, deployment scale ranging up to >1 meter aperture width. Simulations at an aperture widths less than approximately 0.5 m with geometric gains ~100x predict an overall optical efficiency in the range 60-70% for angles up to 50 degrees from normal. However, the

  19. National Solar Thermal Test Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The National Solar Thermal Test Facility (NSTTF) is the only test facility in the United States of its type. This unique facility provides experimental engineering...

  20. Components of solar thermal systems

    OpenAIRE

    Mendes, J. Farinha; Carvalho, M.J.; Schossig, Peter

    2013-01-01

    The heat production sub-system is the part of the overall system which provides heat to a thermally driven air-conditioning system. With regards to the solar-driven equipment, the solar collector is the main component of the sub-system. A brief review on the present state-of-the-art with respect to performance characteristics and available certification schemes of solar collectors is given in the following chapter. Besides the solar collector field, the storage unit and the back-up heat sourc...

  1. PV-enhanced solar thermal power

    OpenAIRE

    Platzer, W.

    2014-01-01

    Solar electricity generation using concentrating solar thermal collectors faces the challenge of strongly decreased levelized electricity costs by photovoltaic power plants. One of the selling points favouring solar thermal power is the possibility to generate dispatchable power. Concepts discussed here are solar hybridization of conventional or biomass thermal power plants. Another option is the use of thermal energy storage (TES) charged with solar heat which allow to drive the generation o...

  2. Drainback solar thermal systems

    DEFF Research Database (Denmark)

    Botpaev, R.; Louvet, Y.; Perers, Bengt

    2016-01-01

    Although solar drainback systems have been used for a long time, they are still generating questions regarding smooth functioning. This paper summarises publications on drainback systems and compiles the current knowledge, experiences, and ideas on the technology. The collective research exhibits...... of this technology has been developed, with a brief description of each hydraulic typology. The operating modes have been split into three stages: filling, operation, and draining, which have been studied separately. A difference in the minimal filling velocities for a siphon development in the solar loop has been...

  3. Drainback solar thermal systems

    DEFF Research Database (Denmark)

    Botpaev, R.; Louvet, Y.; Perers, Bengt

    2016-01-01

    Although solar drainback systems have been used for a long time, they are still generating questions regarding smooth functioning. This paper summarises publications on drainback systems and compiles the current knowledge, experiences, and ideas on the technology. The collective research exhibits...

  4. Solar thermal roofs; Zonthermische daken

    Energy Technology Data Exchange (ETDEWEB)

    Van de Waerdt, J. [DWA installatie- en energieadvies, Bodegraven (Netherlands)

    2012-11-15

    The purpose of the brochure is to increase the effective application of solar thermal roofs. The target group includes consultants, installers, architects and contractors. Attention is paid to the design, parameters for comparison, yield simulations and experiences gained in projects [Dutch] Het doel van de brochure is het vergroten van de effectieve toepassing van zonthermische daken. Tot de doelgroep behoren installatieadviseurs, installateurs, architecten en opdrachtgevers in de bouw. Aandacht wordt besteed aan het ontwerp, parameters voor vergelijking, opbrengstsimulaties en ervaringen opgedaan in projecten.

  5. Solar panel thermal cycling testing by solar simulation and infrared radiation methods

    Science.gov (United States)

    Nuss, H. E.

    1980-01-01

    For the solar panels of the European Space Agency (ESA) satellites OTS/MAROTS and ECS/MARECS the thermal cycling tests were performed by using solar simulation methods. The performance data of two different solar simulators used and the thermal test results are described. The solar simulation thermal cycling tests for the ECS/MARECS solar panels were carried out with the aid of a rotatable multipanel test rig by which simultaneous testing of three solar panels was possible. As an alternative thermal test method, the capability of an infrared radiation method was studied and infrared simulation tests for the ultralight panel and the INTELSAT 5 solar panels were performed. The setup and the characteristics of the infrared radiation unit using a quartz lamp array of approx. 15 sq and LN2-cooled shutter and the thermal test results are presented. The irradiation uniformity, the solar panel temperature distribution, temperature changing rates for both test methods are compared. Results indicate the infrared simulation is an effective solar panel thermal testing method.

  6. Solar energy thermalization and storage device

    Science.gov (United States)

    McClelland, J.F.

    A passive solar thermalization and thermal energy storage assembly which is visually transparent is described. The assembly consists of two substantial parallel, transparent wall members mounted in a rectangular support frame to form a liquid-tight chamber. A semitransparent thermalization plate is located in the chamber, substantially paralled to and about equidistant from the transparent wall members to thermalize solar radiation which is stored in a transparent thermal energy storage liquid which fills the chamber. A number of the devices, as modules, can be stacked together to construct a visually transparent, thermal storage wall for passive solar-heated buildings.

  7. Polymeric materials for solar thermal applications

    CERN Document Server

    Köhl, Michael; Papillon, Philippe; Wallner, Gernot M; Saile, Sandrin

    2012-01-01

    Bridging the gap between basic science and technological applications, this is the first book devoted to polymers for solar thermal applications.Clearly divided into three major parts, the contributions are written by experts on solar thermal applications and polymer scientists alike. The first part explains the fundamentals of solar thermal energy especially for representatives of the plastics industry and researchers. Part two then goes on to provide introductory information on polymeric materials and processing for solar thermal experts. The third part combines both of these fields, dis

  8. Solar engineering of thermal processes

    Science.gov (United States)

    Duffie, J. A.; Beckman, W. A.

    The book focuses on solar radiation characteristics, solar radiation available for practical applications, heat transfer, radiation characteristics of opaque materials, theory of flat-plate collectors, and concentrating collectors. Also discussed are solar process economics, solar water heating, solar heating system design, solar cooling, conversion to mechanical energy, evaporative processes, and selfgradient ponds.

  9. Pv-Thermal Solar Power Assembly

    Science.gov (United States)

    Ansley, Jeffrey H.; Botkin, Jonathan D.; Dinwoodie, Thomas L.

    2001-10-02

    A flexible solar power assembly includes a flexible photovoltaic device attached to a flexible thermal solar collector. The solar power assembly can be rolled up for transport and then unrolled for installation on a surface, such as the roof or side wall of a building or other structure, by use of adhesive and/or other types of fasteners.

  10. Solar thermal systems successful planning and construction

    CERN Document Server

    Peuser, Dr Felix A; Schnauss, Martin

    2013-01-01

    Solar Thermal Systems summarizes the theoretical and practical knowledge gained from over 20 years of research, implementation and operation of thermal solar installations. This work provides answers to a variety of key questions by examining current solar installations, drawing upon past experiences and making proposals for future planning.- how do system components and materials behave under continuous operation?- which components have proven themselves and how are they used properly?- what are the causes of defects and how can they be avoided?- how long is the service life of modern solar i

  11. Solar thermal power systems. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

    Each of DOE's solar Thermal Power Systems projects funded and/or in existence during FY 1978 is described and the status as of September 30, 1978 is reflected. These projects are divided as follows: small thermal power applications, large thermal power applications, and advanced thermal technology. Also included are: 1978 project summary tables, bibliography, and an alphabetical index of contractors. (MHR)

  12. Ultrafast Thermal Cycling of Solar Panels

    National Research Council Canada - National Science Library

    Wall, T

    1998-01-01

    Two new cyclers that utilize a novel hybrid approach to perform fast thermal cycling of solar panels have been built and are now operational in the Mechanics and Materials Technology Center at The Aerospace Corporation...

  13. Forecasting European thermal coal spot prices

    Directory of Open Access Journals (Sweden)

    Alicja Krzemień

    2015-01-01

    Finally, in order to analyse the time series model performance a Generalized Regression Neural Network (GRNN was used and its performance compared against the whole AR(2 process. Empirical results obtained confirmed that there is no statistically significant difference between both methods. The GRNN analysis also allowed pointing out the main drivers that move the European Thermal Coal Spot prices: crude oil, USD/CNY change and supply side drivers.

  14. Solar thermal power systems. Summary report

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The work accomplished by the Aerospace Corporation from April 1973 through November 1979 in the mission analysis of solar thermal power systems is summarized. Sponsorship of this effort was initiated by the National Science Foundation, continued by the Energy Research and Development Administration, and most recently directed by the United States Department of Energy, Division of Solar Thermal Systems. Major findings and conclusions are sumarized for large power systems, small power systems, solar total energy systems, and solar irrigation systems, as well as special studies in the areas of energy storage, industrial process heat, and solar fuels and chemicals. The various data bases and computer programs utilized in these studies are described, and tables are provided listing financial and solar cost assumptions for each study. An extensive bibliography is included to facilitate review of specific study results and methodology.

  15. PV/thermal solar power assembly

    Science.gov (United States)

    Ansley, Jeffrey H.; Botkin, Jonathan D.; Dinwoodie, Thomas L.

    2004-01-13

    A flexible solar power assembly (2) includes a flexible photovoltaic device (16) attached to a flexible thermal solar collector (4). The solar power assembly can be rolled up for transport and then unrolled for installation on a surface, such as the roof (20, 25) or side wall of a building or other structure, by use of adhesive and/or other types of fasteners (23).

  16. Solar thermal production of zinc: Program strategy

    Energy Technology Data Exchange (ETDEWEB)

    Steinfeld, A.; Weidenkaff, A.; Moeller, S.; Palumbo, R. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The solar thermal production of zinc is considered for the conversion of solar energy into storable and transportable chemical fuels. The ultimate objective is to develop a technically and economically viable technology that can produce solar zinc. The program strategy for achieving such a goal involves research on two paths: a direct path via the solar thermal splitting of ZnO in the absence of fossil fuels, and an indirect path via the solar carbothermal/CH{sub 4}-thermal reduction of Zn O, with fossil fuels (coke or natural gas) as chemical reducing agents. Both paths make use of concentrated solar energy for high-temperature process heat. The direct path brings us to the complete substitution of fossil fuels with solar fuels for a sustainable energy supply system. The indirect path creates a link between today`s fossil-fuel-based technology and tomorrow`s solar chemical technology and builds bridges between present and future energy economies. (author) 1 fig., 15 refs.

  17. Thermal Efficiency of Natural Convection Solar Dryer

    Science.gov (United States)

    Seetapong, N.; Chulok, S.; Khoonphunnarai, P.

    2017-09-01

    The purpose of this research is to study the thermal efficiency of natural convection. The working principle of natural convection solar dryer is, once the air in the solar dryer is heated by solar energy, the air relative humidity will drop and floating up through the drying. This air will take moisture out of the product and flow out to the ambient air. It was found from the experiment that, in the duration of 8.00 am - 4.00 pm on a clear sky day, an all-day average ambient air and inside the chamber temperature were 38.34°C and 63.19°C respectively. At the solar radiation intensity of 759.53W/m2, mass flow rate of air was 0.023 kg/s and the thermal efficiency of the solar dryer was 2.59%.

  18. Solar thermal repowering systems integration. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Dubberly, L. J.; Gormely, J. E.; McKenzie, A. W.

    1979-08-01

    This report is a solar repowering integration analysis which defines the balance-of-plant characteristics and costs associated with the solar thermal repowering of existing gas/oil-fired electric generating plants. Solar repowering interface requirements for water/steam and salt or sodium-cooled central receivers are defined for unit sizes ranging from 50 MWe non-reheat to 350 MWe reheat. Finally balance-of-plant cost estimates are presented for each of six combinations of plant type, receiver type and percent solar repowering.

  19. The Polarization Optics for the European Solar Telescope

    NARCIS (Netherlands)

    Bettonvil, F.C.M.|info:eu-repo/dai/nl/304846228; Collados, M.; Feller, A.; Gelly, B. F.; Keller, C.U.|info:eu-repo/dai/nl/304824550; Kentischer, T. J.; López Ariste, A.; Pleier, O.; Snik, F.|info:eu-repo/dai/nl/304832154; Socas-Navarro, H.

    2010-01-01

    EST, the European Solar Telescope, is a 4-m class solar telescope, which will be located at the Canary Islands. It is currently in the conceptual design phase as a European funded project. In order to fulfill the stringent requirements for polarimetric sensitivity and accuracy, the polarimetry has

  20. Hybrids of Solar Sail, Solar Electric, and Solar Thermal Propulsion for Solar-System Exploration

    Science.gov (United States)

    Wilcox, Brian H.

    2012-01-01

    Solar sails have long been known to be an attractive method of propulsion in the inner solar system if the areal density of the overall spacecraft (S/C) could be reduced to approx.10 g/sq m. It has also long been recognized that the figure (precise shape) of useful solar sails needs to be reasonably good, so that the reflected light goes mostly in the desired direction. If one could make large reflective surfaces with reasonable figure at an areal density of approx.10 g/sq m, then several other attractive options emerge. One is to use such sails as solar concentrators for solar-electric propulsion. Current flight solar arrays have a specific output of approx. 100W/kg at 1 Astronomical Unit (AU) from the sun, and near-term advances promise to significantly increase this figure. A S/C with an areal density of 10 g/sq m could accelerate up to 29 km/s per year as a solar sail at 1 AU. Using the same sail as a concentrator at 30 AU, the same spacecraft could have up to approx. 45 W of electric power per kg of total S/C mass available for electric propulsion (EP). With an EP system that is 50% power-efficient, exhausting 10% of the initial S/C mass per year as propellant, the exhaust velocity is approx. 119 km/s and the acceleration is approx. 12 km/s per year. This hybrid thus opens attractive options for missions to the outer solar system, including sample-return missions. If solar-thermal propulsion were perfected, it would offer an attractive intermediate between solar sailing in the inner solar system and solar electric propulsion for the outer solar system. In the example above, both the solar sail and solar electric systems don't have a specific impulse that is near-optimal for the mission. Solar thermal propulsion, with an exhaust velocity of the order of 10 km/s, is better matched to many solar system exploration missions. This paper derives the basic relationships between these three propulsion options and gives examples of missions that might be enabled by

  1. CEN standards for solar thermal systems - State of the art and expectted impact

    NARCIS (Netherlands)

    Ree, B.G.C. van der; Pauschinger, Th.

    1996-01-01

    Since 1994, the European Committee for Standardization (CEN) Technical Committee TC 312 has been active in producing European Standards for thermal solar energy systems and components. In this paper, an overview of the present State of the Art of the draft standards is presented. These standards

  2. Solar thermal electric power information user study

    Energy Technology Data Exchange (ETDEWEB)

    Belew, W.W.; Wood, B.L.; Marle, T.L.; Reinhardt, C.L.

    1981-02-01

    The results of a series of telephone interviews with groups of users of information on solar thermal electric power are described. These results, part of a larger study on many different solar technologies, identify types of information each group needed and the best ways to get information to each group. The report is 1 of 10 discussing study results. The overall study provides baseline data about information needs in the solar community. An earlier study identified the information user groups in the solar community and the priority (to accelerate solar energy commercialization) of getting information to each group. In the current study only high-priority groups were examined. Results from five solar thermal electric power groups of respondents are analyzed: DOE-Funded Researchers, Non-DOE-Funded Researchers, Representatives of Utilities, Electric Power Engineers, and Educators. The data will be used as input to the determination of information products and services the Solar Energy Research Institute, the Solar Energy Information Data Bank Network, and the entire information outreach community should be preparing and disseminating.

  3. The pier and building of the European Solar Telescope (EST)

    Science.gov (United States)

    Bettonvil, F. C. M.; Codina, R.; Gómez Merchán, A.; Hammerschlag, R. H.; Hartman, J. J. M.; Hernández Suárez, E.; Jägers, A. P. L.; Murga Llano, G.; Pelser, J. W.; Sliepen, G.

    2010-07-01

    EST (European Solar Telescope) is a 4-m class solar telescope, which is currently in the conceptual design phase. EST will be located in the Canary Islands and will aim at high spectral, spatial and temporal resolution observations in the photosphere and chromosphere, using a suite of instruments that can produce efficiently two-dimensional spectropolarimetric information of the thermal, dynamic and magnetic properties of the plasma over many scale heights. The pier is defined as the construction that supports the telescope and the enclosure. It needs a certain height to minimize daytime ground turbulence. At the bottom of the pier a large instrument lab is located, 16 m in diameter and 10 m high. To the pier is attached a service building that accommodates all auxiliary services, possibly together with a separate building. Solid concrete- and open framework piers are compared, in terms of stability, thermal properties and flow characteristics and building structures in terms of construction issues. FE and CFD analysis are used to give qualitative insight in the differences between the alternatives. The preferred alternative is a cone shaped pier surrounded by an open framework.

  4. Solar thermal plant impact analysis and requirements definition study

    Science.gov (United States)

    1982-01-01

    The technology and economics of solar thermal electric systems (STES) for electric power production is discussed. The impacts of and requirements for solar thermal electric power systems were evaluated.

  5. Solar thermal harvesting for enhanced photocatalytic reactions.

    Science.gov (United States)

    Hashemi, Seyyed Mohammad Hosseini; Choi, Jae-Woo; Psaltis, Demetri

    2014-03-21

    The Shockley-Queisser limit predicts a maximum efficiency of 30% for single junction photovoltaic (PV) cells. The rest of the solar energy is lost as heat and due to phenomena such as reflection and transmission through the PV and charge carrier recombination. In the case of photocatalysis, this maximum value is smaller since the charge carriers should be transferred to acceptor molecules rather than conductive electrodes. With this perspective, we realize that at least 70% of the solar energy is available to be converted into heat. This is specifically useful for photocatalysis, since heat can provide more kinetic energy to the reactants and increase the number of energetic collisions leading to the breakage of chemical bonds. Even in natural photosynthesis, at the most 6% of the solar spectrum is used to produce sugar and the rest of the absorbed photons are converted into heat in a process called transpiration. The role of this heating component is often overlooked; in this paper, we demonstrate a coupled system of solar thermal and photocatalytic decontamination of water by titania, the most widely used photocatalyst for various photo reactions. The enhancement of this photothermal process over solely photocatalytic water decontamination is demonstrated to be 82% at 1× sun. Our findings suggest that the combination of solar thermal energy capture with photocatalysis is a suitable strategy to utilize more of the solar spectrum and improve the overall performance.

  6. Flexible thermal cycle test equipment for concentrator solar cells

    Science.gov (United States)

    Hebert, Peter H [Glendale, CA; Brandt, Randolph J [Palmdale, CA

    2012-06-19

    A system and method for performing thermal stress testing of photovoltaic solar cells is presented. The system and method allows rapid testing of photovoltaic solar cells under controllable thermal conditions. The system and method presents a means of rapidly applying thermal stresses to one or more photovoltaic solar cells in a consistent and repeatable manner.

  7. Full-spectrum volumetric solar thermal conversion via photonic nanofluids.

    Science.gov (United States)

    Liu, Xianglei; Xuan, Yimin

    2017-10-12

    Volumetric solar thermal conversion is an emerging technique for a plethora of applications such as solar thermal power generation, desalination, and solar water splitting. However, achieving broadband solar thermal absorption via dilute nanofluids is still a daunting challenge. In this work, full-spectrum volumetric solar thermal conversion is demonstrated over a thin layer of the proposed 'photonic nanofluids'. The underlying mechanism is found to be the photonic superposition of core resonances, shell plasmons, and core-shell resonances at different wavelengths, whose coexistence is enabled by the broken symmetry of specially designed composite nanoparticles, i.e., Janus nanoparticles. The solar thermal conversion efficiency can be improved by 10.8% compared with core-shell nanofluids. The extinction coefficient of Janus dimers with various configurations is also investigated to unveil the effects of particle couplings. This work provides the possibility to achieve full-spectrum volumetric solar thermal conversion, and may have potential applications in efficient solar energy harvesting and utilization.

  8. Thermal Performance of an Annealed Pyrolytic Graphite Solar Collector

    Science.gov (United States)

    Jaworske, Donald A.; Hornacek, Jennifer

    2002-01-01

    A solar collector having the combined properties of high solar absorptance, low infrared emittance, and high thermal conductivity is needed for applications where solar energy is to be absorbed and transported for use in minisatellites. Such a solar collector may be used with a low temperature differential heat engine to provide power or with a thermal bus for thermal switching applications. One concept being considered for the solar collector is an Al2O3 cermet coating applied to a thermal conductivity enhanced polished aluminum substrate. The cermet coating provides high solar absorptance and the polished aluminum provides low infrared emittance. Annealed pyrolytic graphite embedded in the aluminum substrate provides enhanced thermal conductivity. The as-measured thermal performance of an annealed pyrolytic graphite thermal conductivity enhanced polished aluminum solar collector, coated with a cermet coating, will be presented.

  9. Renewable Energy Essentials: Concentrating Solar Thermal Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    Concentrated solar thermal power (CSP) is a re-emerging market. The Luz Company built 354 MWe of commercial plants in California, still in operations today, during 1984-1991. Activity re-started with the construction of an 11-MW plant in Spain, and a 64-MW plant in Nevada, by 2006. There are currently hundreds of MW under construction, and thousands of MW under development worldwide. Spain and the United States together represent 90% of the market. Algeria, Egypt and Morocco are building integrated solar combined cycle plants, while Australia, China, India, Iran, Israel, Italy, Jordan, Mexico, South Africa and the United Arab Emirates are finalising or considering projects. While trough technology remains the dominant technology, several important innovations took place over 2007-2009: the first commercial solar towers, the first commercial plants with multi-hour capacities, the first Linear Fresnel Reflector plants went into line.

  10. Solar Thermal Propulsion for Microsatellite Manoeuvring

    Science.gov (United States)

    2004-09-01

    kg), acetylene (614 kJ/kg), and xenon (96.3 kJ/kg) [Lide, 1995][ Air Liquide , 2004]. Solar Thermal Propulsion for Microsatellite Manoeuvring 197...Archives, Kirtland Air Force Base, New Mexico, 2004 [accessed 6 May 2004]. [ Air Liquide , 2004] http://www.airliquide.com/en/business/products/gases...gasdata/index.asp, “Gases,” Air Liquide , Paris, France, March 2004 [accessed 26 March 2004]. [Amass, 2000] http://www.lanternroom.com/misc

  11. Synergies with renewables: Concentrating solar thermal

    Energy Technology Data Exchange (ETDEWEB)

    Louis Wibberley; Aaron Cottrell; Peter Scaife; Phil Brown

    2006-10-15

    This report summarises the status of concentrating solar thermal technology (CST) for the generating of electricity, the synergies and integration with fossil fuel-based generation, and for reforming of natural gas. The report covers information up to September 2005. Overall CST technology has lagged in development and application in comparison with other renewable technologies, such as wind and photovoltaics, but it has been predicted that if the higher rate of commercial application is achieved, the technology will play a significant role in base-load generation for Australia and other countries which have high levels of direct solar insolation. In Australia, the large quantities of natural gas, and coal seam gas and the well developed gas and electricity grids, coupled with large areas with high solar insolation, provide an opportunity for using this approach to make a significant reduction in greenhouse emissions per unit of electricity, and in the amount of fossil energy consumption. CSIRO has a major research program in this area. Of the technologies, parabolic troughs are under the most active development, with the Andasol plant in Spain being the most recent example and with several novel features. The compact linear Fresnel reflector (CLFR) technology being applied at Liddell power station in New South Wales is also an interesting approach, and the recently announced expansion of collector area, and integration into the steam cycle will provide important engineering and operating information. The interaction with coal based electricity generation can be through direct input of solar thermal energy into the steam cycle (as at coal-fired Liddell power station) or through use of the thermal energy to, for example, regenerate sorbents in a post combustion CO{sub 2} capture plant associated with a power station. This latter approach reduces the parasitic power losses from the power station. 36 refs., 37 figs., 11 tabs.

  12. Design and Development of a Solar Thermal Collector with Single Axis Solar Tracking Mechanism

    Directory of Open Access Journals (Sweden)

    Theebhan Mogana

    2016-01-01

    Full Text Available The solar energy is a source of energy that is abundant in Malaysia and can be easily harvested. However, because of the rotation of the Earth about its axis, it is impossible to harvest the solar energy to the maximum capacity if the solar thermal collector is placed fix to a certain angle. In this research, a solar thermal dish with single axis solar tracking mechanism that will rotate the dish according to the position of the sun in the sky is designed and developed, so that more solar rays can be reflected to a focal point and solar thermal energy can be harvested from the focal point. Data were collected for different weather conditions and performance of the solar thermal collector with a solar tracker were studied and compared with stationary solar thermal collector.

  13. Control Optimization of Solar Thermally Driven Chillers

    Directory of Open Access Journals (Sweden)

    Antoine Dalibard

    2016-10-01

    Full Text Available Many installed solar thermally driven cooling systems suffer from high auxiliary electric energy consumption which makes them not more efficient than conventional compression cooling systems. A main reason for this is the use of non-efficient controls with constant set points that do not allow a chiller power modulation at partial-load and therefore lead to unnecessary high power consumption of the parasitics. The aims of this paper are to present a method to control efficiently solar thermally driven chillers, to demonstrate experimentally its applicability and to quantify the benefits. It has been shown that the cooling capacity of a diffusion absorption chiller can be modulated very effectively by adjusting both the temperature and the flow rate of the cooling water. With the developed approach and the use of optimization algorithms, both the temperature and the flow rate can be controlled simultaneously in a way that the cooling load is matched and the electricity consumption is minimized. Depending on the weather and operating conditions, electricity savings between 20% and 60% can be achieved compared to other tested control approaches. The highest savings are obtained when the chiller is operated at partial load. The presented method is not restricted to solar cooling systems and can also be applied to other conventional heating ventilation and air conditioning (HVAC systems.

  14. Solar thermal heating and cooling. A bibliography with abstracts

    Science.gov (United States)

    Arenson, M.

    1979-01-01

    This bibliographic series cites and abstracts the literature and technical papers on the heating and cooling of buildings with solar thermal energy. Over 650 citations are arranged in the following categories: space heating and cooling systems; space heating and cooling models; building energy conservation; architectural considerations, thermal load computations; thermal load measurements, domestic hot water, solar and atmospheric radiation, swimming pools; and economics.

  15. Solar applications of thermal energy storage. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.; Taylor, L.; DeVries, J.; Heibein, S.

    1979-01-01

    A technology assessment is presented on solar energy systems which use thermal energy storage. The study includes characterization of the current state-of-the-art of thermal energy storage, an assessment of the energy storage needs of solar energy systems, and the synthesis of this information into preliminary design criteria which would form the basis for detailed designs of thermal energy storage. (MHR)

  16. Solar Thermal AIR Collector Based on New Type Selective Coating

    National Research Council Canada - National Science Library

    Musiy, R.Y; Midyana, G.G; Makitra, R.G; Vasyutin, J.M; Khovanets, G.I; Zaborowskiy, A.B

    2014-01-01

    Based on the best for optical performance and selective coating solar thermal air collector, which operates by solar power on the principle of simultaneous ventilation and heating facilities, is designed...

  17. Evaluation of solar thermal storage for base load electricity generation

    Directory of Open Access Journals (Sweden)

    Adinberg R.

    2012-10-01

    Full Text Available In order to stabilize solar electric power production during the day and prolong the daily operating cycle for several hours in the nighttime, solar thermal power plants have the options of using either or both solar thermal storage and fossil fuel hybridization. The share of solar energy in the annual electricity production capacity of hybrid solar-fossil power plants without energy storage is only about 20%. As it follows from the computer simulations performed for base load electricity demand, a solar annual capacity as high as 70% can be attained by use of a reasonably large thermal storage capacity of 22 full load operating hours. In this study, the overall power system performance is analyzed with emphasis on energy storage characteristics promoting a high level of sustainability for solar termal electricity production. The basic system parameters, including thermal storage capacity, solar collector size, and annual average daily discharge time, are presented and discussed.

  18. Solar thermal energy. Solar pasteurization of dairy products; Energia solar termica. Pasteurizacion solar

    Energy Technology Data Exchange (ETDEWEB)

    Rosell, J.; Chemisana, D.

    2009-07-01

    Nicaragua is one of the south America countries with biggest cattle figures; however, it is at the bottom of the list of milk consumers. The cause which explains this is a twofold trouble. First of all, they have not the adequate milk treatment methods to guarantee a proper hygienic and conservation conditions. By the other side, production is distributed in small production centers to serve local consumers. this article proposal is to get a pasteurization treatment with thermal processes arranged by means of the solar energy. (Author) 3 refs.

  19. A numerical study of transient, thermally-conductive solar wind

    Science.gov (United States)

    Han, S. M.; Wu, S. T.; Dryer, M.

    1987-01-01

    A numerical analysis of transient solar wind starting at the solar surface and arriving at 1 AU is performed by an implicit numerical method. The model hydrodynamic equations include thermal conduction terms for both steady and unsteady simulations. Simulation results show significant influence of thermal conduction on both steady and time-dependent solar wind. Higher thermal conduction results in higher solar wind speed, higher temperature, but lower plasma density at 1 AU. Higher base temperature at the solar surface gives lower plasma speed, lower temperature, but higher density at 1 AU. Higher base density, on the other hand, gives lower velocity, lower temperature, but higher density at 1 AU.

  20. Thermal analysis and design of passive solar buildings

    CERN Document Server

    Athienitis, AK

    2013-01-01

    Passive solar design techniques are becoming increasingly important in building design. This design reference book takes the building engineer or physicist step-by-step through the thermal analysis and design of passive solar buildings. In particular it emphasises two important topics: the maximum utilization of available solar energy and thermal storage, and the sizing of an appropriate auxiliary heating/cooling system in conjunction with good thermal control.Thermal Analysis and Design of Passive Solar Buildings is an important contribution towards the optimization of buildings as systems th

  1. Recent trends in solar thermal sorption cooling system technology

    Directory of Open Access Journals (Sweden)

    Khaled M Bataineh

    2015-05-01

    Full Text Available Solar thermal cooling is the best alternative solution to overcome the problems associated with using nonrenewable resources. There are several thermal cooling methods developed differing from each other according to the thermodynamic cycle and type of refrigerant used. Recent developments in absorption and adsorption solar cooling systems are presented. Summarized thermodynamic modeling for both absorption and adsorption solar cooling systems is given. Brief thermal analysis among the types of solar collectors is presented. System efficiencies and optimization analysis are presented. The influences of geometrical, system configurations, and physical parameters on the performance of solar thermal sorption cooling system are investigated. The basis for the design of absorption and adsorption solar cooling systems is provided. Several case studies in different climatic conditions are presented. Economic feasibility for both systems is discussed. Comparison between the absorption and adsorption solar cooling system is summarized.

  2. 20. symposium on thermal solar energy. Proceedings; 20. Symposium Thermische Solarenergie. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Within the 20th symposium 'Thermal solar systems'of the Ostbayerisches Technologie-Transfer-Institut e.V. (OTTI) (Regensburg, Federal Republic of Germany) from 5th to 7th May, 2010 in Bad Staffelstein (Federal Republic of Germany) the following lectures were held: (1) State of the art and perspectives of renewable heat (Karin Freier); (2) European perspectives and market overview (Oliver Druecke); (3) 20 Years symposium thermal solar energy (Volker Wittwer); (4) Solar thermal energy 2030 - Potentials, visions, research strategies (Harald Drueck); (5) New perspectives for air collector systems (Gerhard Stryi-Hipp); (6) A new solar thermal desalination system with heat recovery for a central production of drinking water (Tarik Schwarzer); (7) CerapurSolar - Integration of a solar heating support and hot water heating in a gas heater (Konrad Lustig); (8) Possibilities of a heat pipe collector without problems of stagnation (Gerhard Mientkewitz); (9) Flat collector with external reflectors (RefleC): development experiences (Stean Hess); (10) A systematic investigation of the aging behaviour of polymers depending on different loading factors (Karl-Anders Weiss); (11) Development of plastic collectors: Fundamental questions and results from a research project (Stefan Brunold); (12) Experimental and numerical investigations of immersed heat transfer devices for packing and unpacking of hot water storages (William Logie); (13) Testing of layer loading systems under practical conditions (Rolf Lohse); (14) The multifunctional heat storage in Hamburg-Bramfeld - An innovative extension of the oldest German solar community (Thomas Schmidt); (14) HeatBoxQuality - Decentral hydraulic power station on the test rig (Alexander Kaiser); (15) Development of a test procedure for a systematic comparison of fresh water modules (Florian Ruesch); (16) Enlarged system evaluation using the Concise Cylce Test using PelletSolar as an example (Robert Haberl); (17) Functionality

  3. The thermal infrared continuum in solar flares

    Science.gov (United States)

    Fletcher, Lyndsay; Simoes, Paulo; Kerr, Graham Stewart; Hudson, Hugh S.; Gimenez de Castro, C. Guillermo; Penn, Matthew J.

    2017-08-01

    Observations of the Sun with the Atacama Large Millimeter Array have now started, and the thermal infrared will regularly be accessible from the NSF’s Daniel K. Inouye Solar Telescope. Motivated by the prospect of these new observations, and by recent flare detections in the mid infrared, we set out here to model and understand the source of the infrared continuum in flares, and to explore its diagnostic capability for the physical conditions in the flare atmosphere. We use the 1D radiation hydrodynamics code RADYN to calculate mid-infrared continuum emission from model atmospheres undergoing sudden deposition of energy by non-thermal electrons. We identify and characterise the main continuum thermal emission processes relevant to flare intensity enhancement in the mid- to far-infrared (2-200 micron) spectral range as free-free emission on neutrals and ions. We find that the infrared intensity evolution tracks the energy input to within a second, albeit with a lingering intensity enhancement, and provides a very direct indication of the evolution of the atmospheric ionization. The prediction of highly impulsive emission means that, on these timescales, the atmospheric hydrodynamics need not be considered in analysing the mid-IR signatures.

  4. Passive Collecting of Solar Radiation Energy using Transparent Thermal Insulators, Energetic Efficiency of Transparent Thermal Insulators

    OpenAIRE

    Smajo Sulejmanovic; Suad Kunosic; Ema Hankic

    2014-01-01

    This paper explains passive collection of solar radiation energy using transparent thermal insulators. Transparent thermal insulators are transparent for sunlight, at the same time those are very good thermal insulators. Transparent thermal insulators can be placed instead of standard conventional thermal insulators and additionally transparent insulators can capture solar radiation, transform it into heat and save heat just as standard insulators. Using transparent insulators would lead to r...

  5. The role of Solar thermal in Future Energy Systems

    DEFF Research Database (Denmark)

    Mathiesen, Brian Vad; Hansen, Kenneth

    2017-01-01

    This report deals with solar thermal technologies and investigates possible roles for solar thermal in future energy systems for four national energy systems; Germany, Austria, Italy and Denmark. The project period started in January 2014 and finished by October 2017. This report is based...

  6. Rankine-Brayton engine powered solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L [Livermore, CA

    2009-12-29

    A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  7. Rankline-Brayton engine powered solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L [Livermore, CA

    2012-03-13

    A solar thermal powered aircraft powered by heat energy from the sun. A Rankine-Brayton hybrid cycle heat engine is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller or other mechanism for enabling sustained free flight. The Rankine-Brayton engine has a thermal battery, preferably containing a lithium-hydride and lithium mixture, operably connected to it so that heat is supplied from the thermal battery to a working fluid. A solar concentrator, such as reflective parabolic trough, is movably connected to an optically transparent section of the aircraft body for receiving and concentrating solar energy from within the aircraft. Concentrated solar energy is collected by a heat collection and transport conduit, and heat transported to the thermal battery. A solar tracker includes a heliostat for determining optimal alignment with the sun, and a drive motor actuating the solar concentrator into optimal alignment with the sun based on a determination by the heliostat.

  8. Transient Simulation of Line-Focus Solar Thermal Power Plants

    OpenAIRE

    do amaral Burghi, Ana Carolina

    2016-01-01

    Concentrated Solar Power (CSP) is a utility scale technology that pro duces electricity using the thermal energy of the sun. Due to the varying intensity of the solar irradiation, there is a constant change in the op eration point for solar thermal power plants. In order to optimize the process, a complex relation between irradiation intensity, fluid mass fl ow and collector focus must be considered and appropriate control strategies should take into account the transient...

  9. Thermally-induced structural motions of satellite solar arrays

    Science.gov (United States)

    Johnston, John Dennis

    1999-11-01

    Satellites have experienced attitude disturbances resulting from thermally. induced structural motions of flexible appendages since the early days of the space program. Thermally-induced structural motions are typically initiated during orbital eclipse transitions when a satellite exits from or enters into the Earth's shadow. The accompanying rapid changes in thermal loading may lead to time-varying temperature differences through the cross-section of appendages resulting in differential thermal expansion and corresponding structural deformations. Since the total angular momentum of the system must be conserved, motions of flexible appendages such as booms and solar arrays result in rigid body rotations of the entire satellite. These potentially large attitude disturbances may violate satellite pointing and jitter requirements. This research investigates thermally-induced structural motions of rigid panel solar arrays (solar panels) through analytical and experimental studies. Orbital eclipse transition heating and thermal analyses were completed to study solar panel thermal behavior and provide results for input to dynamics analyses. A hybrid coordinate dynamical model was utilized to study the planar dynamics of a simple satellite consisting of a rigid hub with a cantilevered flexible solar panel undergoing thermally-induced structural motions. Laboratory experimental studies were carried out to gain new insight into thermal-structural behavior and to validate analytical models. The experimental studies investigated the thermal-structural performance of honeycomb sandwich panels and satellite solar panel hardware subject to simulated eclipse transition heating. Results from the analytical and experimental studies illustrate the importance of the through-the-thickness temperature difference and its time derivatives as well as the ratio of the characteristic thermal and structural response times in solar panel thermally-induced structural motions. The thermal

  10. Thermal losses od solar distiller assisted with accumulator solar collector; Perdidas termicas del destilador solar asistido con colector solar acumalador

    Energy Technology Data Exchange (ETDEWEB)

    Esteban, C.; Fasulo, A.; Franco, J.

    2004-07-01

    In the Laboratory of Solar Energy of the National University of San Luis (Argentina), we have developed and tested a solar collector accumulator of simple characteristics. The same one consists in a tank of stainless steel, covered with black paint, circular section, and thermically protected with several layers of alveolar polycarbonate. It was considered that a good application for this device would be the feeding thermal assistant for a basin-type distiller. It was constructed and the new solar distiller's behavior was evaluated. With the purpose of introducing improvements in the new still we study their thermal losses. We find that to increase the efficiency of the new device it is necessary: to diminish the thermal losses increasing the insulation, and to increase the efficiency in the collection of solar radiation. (Author)

  11. Towards standardization of in-site parabolic trough collector testing in solar thermal power plants

    Science.gov (United States)

    Sallaberry, Fabienne; Valenzuela, Loreto; de Jalón, Alberto García; Leon, Javier; Bernad, Ignacio David

    2016-05-01

    This paper presents a summary of the testing procedure and a validation of the methodology of parabolic trough collector in solar thermal power plants. The applied testing methodology is the one proposed within the Spanish standardization sub-committee AEN/CTN 206/SC117 working group WG2 related to the components for solar thermal power plants. This methodology is also proposed within the international committee IEC TC 117 (Standard draft IEC 62862-3-2 Ed. 1.0). This study is done at Plataforma Solar de Almería (PSA) in Almeria within the European project STAGE-STE. This paper presents the results of the optical and thermal efficiency of a large-size parabolic trough collector. The obtained values are similar to the previous analysis on this collector by PSA. The results of the tracking system have a good accuracy compared to the acceptance angle of the concentrator.

  12. INFORMATION SUPPLY FOR SOLAR THERMAL SYSTEMS MATHEMATICAL MODELING

    Directory of Open Access Journals (Sweden)

    Kitaytseva Elena Khalilovna

    2017-07-01

    Full Text Available Solar thermal system are its constituent elements with their connection between each other, thermal processes within them and also input/output data. The conjunction of external and internal factors determines the efficiency of solar thermal system. No excess heat as well as its deficiency displays us high level efficiency of system. The initial data for modeling of solar thermal systems functioning are dissimilar. Parameters of system’s equipment are constant. Solar radiation amount and water consumption are variable data. The more close initial data to reality, the more definite simulated result is. The main problem is in unpredictability of water consumption by the reason of daily regime and requirement of each user. In this way user is the most instable element of the system. In this study the input data for mathematical modeling of solar thermal systems was analyzed. The climatic databases and standard specifications of hot water demand were also analyzed. The operability estimation method for solar thermal systems with variable input data was offered. The extent of suitability of any solar thermal system can be defined by certain characteristic. The value of this characteristic displays energy accumulation process.

  13. Development of a solar thermal thruster system

    NARCIS (Netherlands)

    Leenders, H.C.M.; Zandbergen, B.T.C.

    2008-01-01

    At the Delft University of Technology the use of solar radiation to heat a propellant to a high temperature is investigated as an alternative to resistance heating. The latter only allows for a solar power to heat conversion efficiency of about 25%, depending on the solar cells, whereas for solar

  14. LEMUR: Large European Module for Solar Ultraviolet Research

    Science.gov (United States)

    Teriaca, Luca; Vincenzo, Andretta; Auchere, Frederic; Brown, Charles M.; Buchlin, Eric; Cauzzi, Gianna; Culhane, J. Len; Curdt, Werner; Davila, Joseph M.; Del Zanna, Giulio; hide

    2012-01-01

    The solar outer atmosphere is an extremely dynamic environment characterized by the continuous interplay between the plasma and the magnetic field that generates and permeates it. Such interactions play a fundamental role in hugely diverse astrophysical systems, but occur at scales that cannot be studied outside the solar system. Understanding this complex system requires concerted, simultaneous solar observations from the visible to the vacuum ultraviolet (VUV) and soft X-rays, at high spatial resolution (between 0.1'' and 0.3''), at high temporal resolution (on the order of 10 s, i.e., the time scale of chromospheric dynamics), with a wide temperature coverage (0.01 MK to 20 MK, from the chromosphere to the flaring corona), and the capability of measuring magnetic fields through spectropolarimetry at visible and near-infrared wavelengths. Simultaneous spectroscopic measurements sampling the entire temperature range are particularly important. These requirements are fulfilled by the Japanese Solar-C mission (Plan B), composed of a spacecraft in a geosynchronous orbit with a payload providing a significant improvement of imaging and spectropolarimetric capabilities in the UV, visible, and near-infrared with respect to what is available today and foreseen in the near future. The Large European Module for solar Ultraviolet Research (LEMUR), described in this paper, is a large VUV telescope feeding a scientific payload of high-resolution imaging spectrographs and cameras. LEMUR consists of two major components: a VUV solar telescope with a 30 cm diameter mirror and a focal length of 3.6 m, and a focal-plane package composed of VUV spectrometers covering six carefully chosen wavelength ranges between 170 Angstrom and 1270 Angstrom. The LEMUR slit covers 280'' on the Sun with 0.14'' per pixel sampling. In addition, LEMUR is capable of measuring mass flows velocities (line shifts) down to 2 km s - 1 or better. LEMUR has been proposed to ESA as the European contribution

  15. Thermal performance of solar district heating plants in Denmark

    DEFF Research Database (Denmark)

    Furbo, Simon; Perers, Bengt; Bava, Federico

    2014-01-01

    The market for solar heating plants connected to district heating systems is expanding rapidly in Denmark. It is expected that by the end of 2014 the 10 largest solar heating plants in Europe will be located in Denmark. Measurements from 23 Danish solar heating plants, all based on flat plate solar...... collectors mounted on the ground, shows measured yearly thermal performances of the solar heating plants placed in the interval from 313 kWh/m² collector to 493 kWh/m² collector with averages for all plants of 411 kWh/m² collector for 2012 and 450 kWh/m² collector for 2013. Theoretical calculations show...... of the cost/performance ratio for solar collector fields, both with flat plate collectors and with concentrating tracking solar collectors. It is recommended to continue monitoring and analysis of all large solar heating plants to document the reliability of the solar heating plants. It is also recommended...

  16. Solar thermal power meeting - Proceedings; Les Rencontres du Solaire Thermodynamique - Actes

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-15

    This document summarizes the presentations and debates of the first edition of the Solar thermal power meeting. Content: 1 - Opening talk (Jean-Louis BAL, SER); 2 - Solar thermal power, European and global road-maps (Cedric Philibert, IEA; Mariangels Perez Latorre, Estela); 3 - first round-table on the international development of solar energy (Philippe Lorec, DGEC France; Said Mouline, Aderee Morocco; Obaid Amrane, Masen Morocco; Kawther Lihidheb, ANME Tunisia; Abdelaziz Boumahra, Rouiba Eclairage, Algeria; Badis Derradji, NEAL Algeria; Yao Azoumah, Lesee, 2IE Foundation Burkina Faso; Mamadou Amadou Kane, MPEM Mauritania; Jean-Charles Mulet, Bertin Technologies); 4 - Second round-table on the French solar thermal offer for export (Georgina Grenon, DGEC; Stephanie Bouzigueseschmann, DG Tresor; Armand Pineda, Alstom; Florent Brunet, Mena-Areva; Roger Pujol, CNIM; Gilles David, Enertime; Michel Wohrer, Saed; Mathieu Vrinat, Sogreah; Marc Benmarraze, Solar Euromed; 5 - Presentation of Amisole - Moroccan association of solar and wind industries (Ahmed Squalli, Amisole); 6 - Third round-table on French research at the solar industry service (Gilles Flamant, Promes Lab. CNRS; Francois Moisan, Ademe; Tahar Melliti, CGI; Andre Joffre, Derbi; Michel Wohrer, Capenergies; 7 - Fourth round table on projects financing (Vincent Girard, Loan Officer BEI; Bertrand Marchais, Miga World Bank; Philippe Meunier, CDC Climat Groupe Caisse des Depots; Christian de Gromard, AFD; Laurent Belouze, Natixis; Piotr Michalowski, Loan Officer BEI); 8 - Closing of the meeting (Roger Pujol, SER)

  17. Beam-Forming Concentrating Solar Thermal Array Power Systems

    Science.gov (United States)

    Cwik, Thomas A. (Inventor); Dimotakis, Paul E. (Inventor); Hoppe, Daniel J. (Inventor)

    2016-01-01

    The present invention relates to concentrating solar-power systems and, more particularly, beam-forming concentrating solar thermal array power systems. A solar thermal array power system is provided, including a plurality of solar concentrators arranged in pods. Each solar concentrator includes a solar collector, one or more beam-forming elements, and one or more beam-steering elements. The solar collector is dimensioned to collect and divert incoming rays of sunlight. The beam-forming elements intercept the diverted rays of sunlight, and are shaped to concentrate the rays of sunlight into a beam. The steering elements are shaped, dimensioned, positioned, and/or oriented to deflect the beam toward a beam output path. The beams from the concentrators are converted to heat at a receiver, and the heat may be temporarily stored or directly used to generate electricity.

  18. A new thermal and rheological model of the European lithosphere

    NARCIS (Netherlands)

    Tesauro, M.; Kaban, M.; Cloetingh, S.A.P.L.

    2009-01-01

    We present a new thermal and rheological model of the European lithosphere (10°W-35°E; 35°N-60°N), which is based on a combination of recently obtained geophysical models. To determine temperature distribution we use a new tomography model, which is principally improved by an a-priori correction of

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

    Science.gov (United States)

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

    1981-01-01

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

  20. Utilization of solar thermal energy in the mining industry: applied case solar thermal systems for hot water heating - Mining camps

    Energy Technology Data Exchange (ETDEWEB)

    Vasquez Mena, Horacio [Portal Sustentable and Enerficaz (Chile)

    2010-07-01

    The paper gives an overview of how solar thermal energy can be used in the mining industry. This is done through a case study of solar thermal systems (STS) for hot water heating in mining camps in Chile. Solar thermal energy has various applications, such as heating and air conditioning. Solar radiation between 600 to 800w/m2 only can be used for solar thermal systems. Solar collectors can be of two types, flat plate or vacuum tube. Various techniques can be used to model solar thermal systems: Transol, RET screen, T-sol, Static model and F-chart. Chile has the great advantage of being one of the countries with the highest levels of solar radiation. Technical data for the solar collector and the heat pump used for the study are given. The collector performance was evaluated throughout the year and the actual results achieved were compared with those projected. The paper concludes that STS are a good source of renewable energy. They are efficient, cheap, and they have a small carbon footprint.

  1. The thermal environment and occupant perceptions in European office buildings

    Energy Technology Data Exchange (ETDEWEB)

    Stoops, J.L. [Chalmers Univ. of Tech., Goeteborg (Sweden). Dept. of Building Services Engineering

    2002-02-01

    The results from a large field study of thermal comfort in European office buildings are reported. Environmental conditions and occupant perceptions were collected over fourteen months from twenty-six different office buildings located in France, Greece, Portugal, Sweden and the UK. This thesis focuses on the thermal measurements and occupant perceptions; however, some of the additional variables with strong connections to thermal sensation are also examined. A summary of human comfort is presented to help place this thesis in appropriate context. The summary presents thermal comfort issues within a broad framework of environmental comfort including physical, physiological, behavioural, psychological and other variables. A more narrowly focused overview of current thermal comfort research is also included. The work attempts to show relationships and produce useful information from the data set by using rather simple statistics and graphical methods. The objective is to quite literally use the data set to illustrate the actual thermal conditions in European office buildings and the occupant perceptions of those conditions. The data are examined in some detail with key relationships identified and explored. Significant differences between countries, both for the physical conditions and the perceptions of those conditions are identified. In addition, the variation over the course of the year for each country is explored. The variations occur in complex ways, which make simple, all encompassing explanations impossible. The nature and size of the variations make the application of simple Europe wide models of thermal comfort questionable. It appears that individuals in different European countries have different expectations for their indoor office thermal environment. This data set will be further explored in a more complete study, which will examine the other measured variables.

  2. Solar-Tep. Solar thermal power. Final report; Solar-Tep. Solare Thermokraft. Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Robert, R.; Weidenkaff, A.

    2006-07-01

    The direct and efficient conversion of concentrated solar radiation into electricity with a high power output requires the development of thermoelectrically active p- and n-type semiconductors with similar material properties which are stable in air at very high temperature. The only suitable materials that fulfil this task are high performance ceramics. We successfully developed and investigated novel perovskite-type transition-metal oxides as potential candidates for thermoelectric devices operating at high temperatures as they can possess large positive as well as large negative thermo-power depending on their composition. The three parameters defining the thermoelectric figure of merit ZT are in most cases interdependent: the thermo-power increases with increasing resistivity. The heat conductivity increases with electrical conductivity. Therefore, an optimum charge carrier concentration and mobility has to be defined, which depends on the substitution level, the spin states of the transition metals, the Ligand field, i.e. the crystallographic structure, the valence states of the cations and ionic deficiencies. The tuning of the thermoelectric properties of the perovskite-type candidates is based on controlled anionic and cationic substitutions. The resulting products are characterised as far as structure and composition are concerned using various methods available at EMPA and at large scale facilities including Xray and Neutron Diffraction, transmission electron microscopy, thermal analysis, synchrotron-radiation-based techniques (EXAFS, XANES, Diffraction) as well as Raman spectroscopy and tested concerning their thermoelectric activity in the new thermoelectricity lab at EMPA. (author)

  3. Thermal performance analysis of a solar heating plant

    DEFF Research Database (Denmark)

    Fan, Jianhua; Huang, Junpeng; Andersen, Ola Lie

    Detailed measurements were carried out on a large scale solar heating plant located in southern Denmark in order to evaluate thermal performances of the plant. Based on the measurements, energy flows of the plant were evaluated. A modified Trnsys model of the Marstal solar heating plant...... was developed to calculate thermal performances of the plant. In the Trnsys model, three solar collector fields with a total solar collector area of 33,300 m2, a seasonal water pit heat storage of 75,000 m3, a simplified CO2 HP, a simplified ORC unit and a simplified wood chip boiler were included. The energy...... consumption of the district heating net was modeled by volume flow rate and given forward and return temperatures of the district heating net. Weather data from a weather station at the site of the plant were used in the calculations. The Trnsys calculated yearly thermal performance of the solar heating plant...

  4. Analysis of regenerative thermal storage geometries for solar gas turbines

    CSIR Research Space (South Africa)

    Klein, P

    2014-08-01

    Full Text Available Ceramic heat regenerators are suited to providing thermal storage for concentrating solar power stations based on a recuperated gas turbine cycle. Randomly packed beds of spheres and saddles; honeycombs and checker bricks were identified...

  5. Photoswitchable Molecular Rings for Solar-Thermal Energy Storage.

    Science.gov (United States)

    Durgun, E; Grossman, Jeffrey C

    2013-03-21

    Solar-thermal fuels reversibly store solar energy in the chemical bonds of molecules by photoconversion, and can release this stored energy in the form of heat upon activation. Many conventional photoswichable molecules could be considered as solar thermal fuels, although they suffer from low energy density or short lifetime in the photoinduced high-energy metastable state, rendering their practical use unfeasible. We present a new approach to the design of chemistries for solar thermal fuel applications, wherein well-known photoswitchable molecules are connected by different linker agents to form molecular rings. This approach allows for a significant increase in both the amount of stored energy per molecule and the stability of the fuels. Our results suggest a range of possibilities for tuning the energy density and thermal stability as a function of the type of the photoswitchable molecule, the ring size, or the type of linkers.

  6. Photoswichable Molecular Rings for Solar-Thermal Energy Storage

    Science.gov (United States)

    Durgun, Engin; Kolpak, Alexie M.; Grossman, Jeffrey C.

    2012-02-01

    Solar-thermal fuels reversibly store solar energy in the chemical bonds of molecules by photoconversion, and can release this stored energy in the form of heat upon activation. Many conventional photoswichable molecules could be considered as solar thermal fuels, although they suffer from low energy density and short lifetime in the photo-excited state, rendering their practical use unfeasible. We present a new approach to design systems for solar thermal fuel applications, wherein well-known photoswitchable molecules are connected by different linker agents to form molecular rings. This approach allows for a significant increase in both the amount of stored energy per molecule and the stability of the fuels. Our results suggest a range of possibilities for tuning the energy density and thermal stability as a function of the type of the photoswitchable molecule, the ring size, and/or the type of linkers.

  7. Engine Optimization for a Solar Thermal Powered Orbit Transfer Vehicle

    Science.gov (United States)

    1998-06-01

    Recent technological advancements in solar thermal rocket propulsion and solar orbit transfer vehicles make it critical to perform additional engine performance analyses. Several system level flight demonstrations are imminent. Space flight hardware component testing is being conducted at the Air Force Research Laboratory, Edwards AFB, California. The focus of current research is engine and nozzle configurations for a solar orbit transfer vehicle. The optimal design must produce 1-10 pounds thrust, perform at high lsp and be compatible in a hybrid of spiral, perigee, and apogee (multi-burn) configurations. The nozzle material must not ablate when subjected to extreme thermal loading, yet be durable enough to withstand widely varying temperature differentials during frequent thermal cycling. This paper addresses propulsive needs in the orbit transfer arena and defines governing upper stage vehicle engine equations. These equations are modified versions of rocket engine equations used for chemical systems. The correction factors and modifications are for Solar Thermal Propulsion specific hardware.

  8. Integrated solar thermal facade component for building energy retrofit

    OpenAIRE

    Giovanardi, Alessia

    2012-01-01

    In the perspective of the "Net Zero Energy Buildings" as specified in the EPBP 2010/31/EU, herein a modular unglazed solar thermal facade component for facilitating the installation of active solar thermal facades has been conceived and designed to answer three considerations: (1) easily installable elements, offering high modularity to be sized for the specific needs of the buildings considered, (2) low-price unglazed technology, given by the industrial process already developed for the frid...

  9. Solar Thermal AIR Collector Based on New Type Selective Coating

    Directory of Open Access Journals (Sweden)

    Musiy, R.Y.

    2014-01-01

    Full Text Available Based on the best for optical performance and selective coating solar thermal air collector, which operates by solar power on the principle of simultaneous ventilation and heating facilities, is designed. It can be used for vacation homes, museums, wooden churches, warehouses, garages, houses, greenhouses etc.

  10. Thermal efficiency of single-pass solar air collector

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim, Zamry; Ibarahim, Zahari; Yatim, Baharudin [School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia); Ruslan, Mohd Hafidz [Solar Energy Research Institute (SERI), Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor Darul Ehsan (Malaysia)

    2013-11-27

    Efficiency of a finned single-pass solar air collector was studied. This paper presents the experimental study to investigate the effect of solar radiation and mass flow rate on efficiency. The fins attached at the back of absorbing plate to improve the thermal efficiency of the system. The results show that the efficiency is increased proportional to solar radiation and mass flow rate. Efficiency of the collector archived steady state when reach to certain value or can be said the maximum performance.

  11. Evaluation of thermal-storage concepts for solar cooling applications

    Science.gov (United States)

    Hughes, P. J.; Morehouse, J. H.; Choi, M. K.; White, N. M.; Scholten, W. B.

    1981-10-01

    Various configuration concepts for utilizing thermal energy storage to improve the thermal and economic performance of solar cooling systems for buildings were analyzed. The storge concepts evaluated provide short-term thermal storge via the bulk containment of water or salt hydrates. The evaluations were made for both residential-size cooling systems (3-ton) and small commercial-size cooling systems (25-ton). The residential analysis considers energy requirements for space heating, space cooling and water heating, while the commercial building analysis is based only on energy requirements for space cooling. The commercial building analysis considered a total of 10 different thermal storage/solar systems, 5 each for absorption and Rankine chiller concepts. The residential analysis considered 4 thermal storage/solar systems, all utilizing an absorption chiller. The trade-offs considered include: cold-side versus hot-side storage, single vs multiple stage storage, and phase-change vs sensible heat storage.

  12. Solar-thermal experimental projects on the Spanish Plataforma Solar

    Science.gov (United States)

    Grasse, W.

    1981-11-01

    The Plataforma Solar with an area of 1,000,000 sq m is located in Spain at a distance of approximately 50 km from the Mediterranean. In May 1979, nine members of the International Energy Agency (IEA) decided to support the construction of Small Solar Power Systems (SSPS). The countries involved include West Germany, the U.S., Spain, and Italy. The SSPS are to demonstrate the operational feasibility of solar technologies which have been mainly developed in Germany and the U.S. In addition, data are to be obtained regarding the relative competitive position of two different operational concepts for SSPS. The concepts are related to the central receiver system (solar tower) and the distributed collector system. Attention is also given to the Spanish solar power station CESA-1 and the German-Spanish technology program GAST, which is to explore the technological limits of solar-energy systems.

  13. Passive Collecting of Solar Radiation Energy using Transparent Thermal Insulators, Energetic Efficiency of Transparent Thermal Insulators

    Directory of Open Access Journals (Sweden)

    Smajo Sulejmanovic

    2014-11-01

    Full Text Available This paper explains passive collection of solar radiation energy using transparent thermal insulators. Transparent thermal insulators are transparent for sunlight, at the same time those are very good thermal insulators. Transparent thermal insulators can be placed instead of standard conventional thermal insulators and additionally transparent insulators can capture solar radiation, transform it into heat and save heat just as standard insulators. Using transparent insulators would lead to reduce in usage of fossil fuels and would help protection of an environment and reduce effects of global warming, etc.

  14. Thermal energy storage for CSP (Concentrating Solar Power

    Directory of Open Access Journals (Sweden)

    Py Xavier

    2017-01-01

    Full Text Available The major advantage of concentrating solar power before photovoltaic is the possibility to store thermal energy at large scale allowing dispatchability. Then, only CSP solar power plants including thermal storage can be operated 24 h/day using exclusively the solar resource. Nevertheless, due to a too low availability in mined nitrate salts, the actual mature technology of the two tanks molten salts cannot be applied to achieve the expected international share in the power production for 2050. Then alternative storage materials are under studies such as natural rocks and recycled ceramics made from industrial wastes. The present paper is a review of those alternative approaches.

  15. Thermal energy storage for CSP (Concentrating Solar Power)

    Science.gov (United States)

    Py, Xavier; Sadiki, Najim; Olives, Régis; Goetz, Vincent; Falcoz, Quentin

    2017-07-01

    The major advantage of concentrating solar power before photovoltaic is the possibility to store thermal energy at large scale allowing dispatchability. Then, only CSP solar power plants including thermal storage can be operated 24 h/day using exclusively the solar resource. Nevertheless, due to a too low availability in mined nitrate salts, the actual mature technology of the two tanks molten salts cannot be applied to achieve the expected international share in the power production for 2050. Then alternative storage materials are under studies such as natural rocks and recycled ceramics made from industrial wastes. The present paper is a review of those alternative approaches.

  16. Thermal performance of a hot-air solar collector

    Science.gov (United States)

    1978-01-01

    Report contains procedures and results of thermal-performance tests on double-glazed air solar collector. Four types of tests were carried out including thermal-efficiency and stagnation tests, collector time-constant tests to assess effects of transients, and incident-angle modifier tests. Data are presented in tables and as graphs and are discussed and analyzed.

  17. Solar-thermal conversion and thermal energy storage of graphene foam-based composites.

    Science.gov (United States)

    Zhang, Lianbin; Li, Renyuan; Tang, Bo; Wang, Peng

    2016-08-14

    Among various utilizations of solar energy, solar-thermal conversion has recently gained renewed research interest due to its extremely high energy efficiency. However, one limiting factor common to all solar-based energy conversion technologies is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy the continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar-thermal conversion and thermal storage for sustained energy release. The composite is obtained by infiltrating the 3D graphene foam with a commonly used PCM, paraffin wax. The high macroporosity and low density of the graphene foam allow for high weight fraction of the PCM to be incorporated, which enhances the heat storage capacity of the composite. The interconnected graphene sheets in the composite provide (1) the solar-thermal conversion capability, (2) high thermal conductivity and (3) form stability of the composite. Under light irradiation, the composite effectively collects and converts the light energy into thermal energy, and the converted thermal energy is stored in the PCM and released in an elongated period of time for sustained utilization. This study provides a promising route for sustainable utilization of solar energy.

  18. Solar-thermal conversion and thermal energy storage of graphene foam-based composite

    KAUST Repository

    Zhang, Lianbin

    2016-07-11

    Among various utilizations of solar energy, solar-thermal conversion has recently gained renewed research interest due to its extremely high energy efficiency. However, one limiting factor common to all solar-based energy conversion technologies is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar-thermal conversion and thermal storage for sustained energy release. The composite is obtained by infiltrating the 3D graphene foam with a commonly used PCM, paraffin wax. The high macroporosity and low density of the graphene foam allow for high weight fraction of the PCM to be incorporated, which enhances heat storage capacity of the composite. The interconnected graphene sheets in the composite provide (1) the solar-thermal conversion capability, (2) high thermal conductivity and (3) form stability of the composite. Under light irradiation, the composite effectively collects and converts the light energy into thermal energy, and the converted thermal energy is stored in the PCM and released in an elongated period of time for sustained utilization. This study provides a promising route for sustainable utilization of solar energy.

  19. Solar thermal bowl concepts and economic comparisons for electricity generation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, T.A.; Dirks, J.A.; Brown, D.R.; Antoniak, Z.I.; Allemann, R.T.; Coomes, E.P.; Craig, S.N.; Drost, M.K.; Humphreys, K.K.; Nomura, K.K.

    1988-04-01

    This study is aimed at providing a relative comparison of the thermodynamic and economic performance in electric applications for fixed mirror distributed focus (FMDF) solar thermal concepts which have been studied and developed in the DOE solar thermal program. Following the completion of earlier systems comparison studies in the late 1970's there have been a number of years of progress in solar thermal technology. This progress includes developing new solar components, improving component and system design details, constructing working systems, and collecting operating data on the systems. This study povides an update of the expected performance and cost of the major components, and an overall system energy cost for the FMDDF concepts evaluated. The projections in this study are for the late 1990's and are based on the potential capabilities that might be achieved with further technology development.

  20. Solar cooling - state of the art of solar thermally driven heat pumps for cooling

    OpenAIRE

    Jakob, Uli

    2013-01-01

    Part of: Thermally driven heat pumps for heating and cooling. – Ed.: Annett Kühn – Berlin: Universitätsverlag der TU Berlin, 2013 ISBN 978-3-7983-2686-6 (print) ISBN 978-3-7983-2596-8 (online) urn:nbn:de:kobv:83-opus4-39458 [http://nbn-resolving.de/urn:nbn:de:kobv:83-opus4-39458] An attractive alternative to conventional electricity driven cooling systems is solar cooling, which combines thermally driven heat pumps/chillers with solar thermal collectors. Solar co...

  1. High temperature solar thermal technology: The North Africa Market

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-01

    High temperature solar thermal (HTST) technology offers an attractive option for both industrialized and non-industrialized countries to generate electricity and industrial process steam. The purpose of this report is to assess the potential market for solar thermal applications in the North African countries of Algeria, Egypt, Morocco and Tunisia. North Africa was selected because of its outstanding solar resource base and the variety of applications to be found there. Diminishing oil and gas resources, coupled with expanding energy needs, opens a large potential market for the US industry. The US high temperature solar trough industry has little competition globally and could build a large market in these areas. The US is already familiar with certain solar markets in North Africa due to the supplying of substantial quantities of US-manufactured flat plate collectors to this region.

  2. Comparison of selective transmitters for solar thermal applications.

    Science.gov (United States)

    Taylor, Robert A; Hewakuruppu, Yasitha; DeJarnette, Drew; Otanicar, Todd P

    2016-05-10

    Solar thermal collectors are radiative heat exchangers. Their efficacy is dictated predominantly by their absorption of short wavelength solar radiation and, importantly, by their emission of long wavelength thermal radiation. In conventional collector designs, the receiver is coated with a selectively absorbing surface (Black Chrome, TiNOx, etc.), which serves both of these aims. As the leading commercial absorber, TiNOx consists of several thin, vapor deposited layers (of metals and ceramics) on a metal substrate. In this technology, the solar absorption to thermal emission ratio can exceed 20. If a solar system requires an analogous transparent component-one which transmits the full AM1.5 solar spectrum, but reflects long wavelength thermal emission-the technology is much less developed. Bespoke "heat mirrors" are available from optics suppliers at high cost, but the closest mass-produced commercial technology is low-e glass. Low-e glasses are designed for visible light transmission and, as such, they reflect up to 50% of available solar energy. To address this technical gap, this study investigated selected combinations of thin films that could be deposited to serve as transparent, selective solar covers. A comparative numerical analysis of feasible materials and configurations was investigated using a nondimensional metric termed the efficiency factor for selectivity (EFS). This metric is dependent on the operation temperature and solar concentration ratio of the system, so our analysis covered the practical range for these parameters. It was found that thin films of indium tin oxide (ITO) and ZnS-Ag-ZnS provided the highest EFS. Of these, ITO represents the more commercially viable solution for large-scale development. Based on these optimized designs, proof-of-concept ITO depositions were fabricated and compared to commercial depositions. Overall, this study presents a systematic guide for creating a new class of selective, transparent optics for solar

  3. 5-Megawatt solar-thermal test facility: environmental assessment

    Energy Technology Data Exchange (ETDEWEB)

    None

    1976-01-30

    An Environmental Assessment of the 5 Megawatt Solar Thermal Test Facility (STTF) is presented. The STTF is located at Albuquerque, New Mexico. The facility will have the capability for testing scale models of major subsystems comprising a solar thermal electrical power plant. The STTF capabilities will include testing a solar energy collector subsystem comprised of heliostat arrays, a receiver subsystem which consists of a boiler/superheater in which a working fluid is heated, and a thermal storage subsystem which includes tanks of high heat capacity material which stores thermal energy for subsequent use. The STTF will include a 200-foot receiver tower on which experimental receivers will be mounted. The Environmental Assessment describes the proposed STTF, its anticipated benefits, and the environment affected. It also evaluates the potential environmental impacts associated with STTF construction and operation.

  4. Residential Solar-Based Seasonal Thermal Storage Systems in Cold Climates: Building Envelope and Thermal Storage

    Directory of Open Access Journals (Sweden)

    Alexandre Hugo

    2012-10-01

    Full Text Available The reduction of electricity use for heating and domestic hot water in cold climates can be achieved by: (1 reducing the heating loads through the improvement of the thermal performance of house envelopes, and (2 using solar energy through a residential solar-based thermal storage system. First, this paper presents the life cycle energy and cost analysis of a typical one-storey detached house, located in Montreal, Canada. Simulation of annual energy use is performed using the TRNSYS software. Second, several design alternatives with improved thermal resistance for walls, ceiling and windows, increased overall air tightness, and increased window-to-wall ratio of South facing windows are evaluated with respect to the life cycle energy use, life cycle emissions and life cycle cost. The solution that minimizes the energy demand is chosen as a reference house for the study of long-term thermal storage. Third, the computer simulation of a solar heating system with solar thermal collectors and long-term thermal storage capacity is presented. Finally, the life cycle cost and life cycle energy use of the solar combisystem are estimated for flat-plate solar collectors and evacuated tube solar collectors, respectively, for the economic and climatic conditions of this study.

  5. Solar radiation and thermal performance of solar collectors for Denmark

    DEFF Research Database (Denmark)

    Dragsted, Janne; Furbo, Simon

    This report describes the part of the EUDP project “EUDP 11-l, Solar Resource Assessment in Denmark”, which is carried out at Department of Civil Engineering, Technical University of Denmark.......This report describes the part of the EUDP project “EUDP 11-l, Solar Resource Assessment in Denmark”, which is carried out at Department of Civil Engineering, Technical University of Denmark....

  6. Solar dryer with thermal storage and biomass-backup heater

    Energy Technology Data Exchange (ETDEWEB)

    Madhlopa, A. [Department of Physics and Biochemical Sciences, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi); Ngwalo, G. [Department of Mechanical Engineering, Malawi Polytechnic, P/Bag 303, Blantyre 3 (Malawi)

    2007-04-15

    An indirect type natural convection solar dryer with integrated collector-storage solar and biomass-backup heaters has been designed, constructed and evaluated. The major components of the dryer are biomass burner (with a rectangular duct and flue gas chimney), collector-storage thermal mass and drying chamber (with a conventional solar chimney). The thermal mass was placed in the top part of the biomass burner enclosure. The dryer was fabricated using simple materials, tools and skills, and it was tested in three modes of operation (solar, biomass and solar-biomass) by drying twelve batches of fresh pineapple (Ananas comosus), with each batch weighing about 20 kg. Meteorological conditions were monitored during the dehydration process. Moisture and vitamin C contents were determined in both fresh and dried samples. Results show that the thermal mass was capable of storing part of the absorbed solar energy and heat from the burner. It was possible to dry a batch of pineapples using solar energy only on clear days. Drying proceeded successfully even under unfavorable weather conditions in the solar-biomass mode of operation. In this operational mode, the dryer reduced the moisture content of pineapple slices from about 669 to 11% (db) and yielded a nutritious dried product. The average values of the final-day moisture-pickup efficiency were 15%, 11% and 13% in the solar, biomass and solar-biomass modes of operation respectively. It appears that the solar dryer is suitable for preservation of pineapples and other fresh foods. Further improvements to the system design are suggested. (author)

  7. Tehachapi solar thermal system first annual report

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, A. [Southwest Technology Development Inst., Las Cruces, NM (US)

    1993-05-01

    The staff of the Southwest Technology Development Institute (SWTDI), in conjunction with the staff of Industrial Solar Technology (IST), have analyzed the performance, operation, and maintenance of a large solar process heat system in use at the 5,000 inmate California Correctional Institution (CCI) in Tehachapi, CA. This report summarizes the key design features of the solar plant, its construction and maintenance histories through the end of 1991, and the performance data collected at the plant by a dedicated on-site data acquisition system (DAS).

  8. Solar thermal power systems. Annual technical progress report, FY 1979

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Gerald W.

    1980-06-01

    The Solar Thermal Power Systems Program is the key element in the national effort to establish solar thermal conversion technologies within the major sectors of the national energy market. It provides for the development of concentrating mirror/lens heat collection and conversion technologies for both central and dispersed receiver applications to produce electricity, provide heat at its point of use in industrial processes, provide heat and electricity in combination for industrial, commercial, and residential needs, and ultimately, drive processes for production of liquid and gaseous fuels. This report is the second Annual Technical Progress Report for the Solar Thermal Power Systems Program and is structured according to the organization of the Solar Thermal Power Systems Program on September 30, 1979. Emphasis is on the technical progress of the projects rather than on activities and individual contractor efforts. Each project description indicates its place in the Solar Thermal Power Systems Program, a brief history, the significant achievements and real progress during FY 1979, also future project activities as well as anticipated significant achievements are forecast. (WHK)

  9. Thermal Testing Methods for Solar Dryers

    DEFF Research Database (Denmark)

    Singh, Shobhana

    2017-01-01

    Solar food drying is a complex heat and mass transfer phenomena which depend on a number of drying process-dependent parameters such as operating conditions and characteristics of the food product to be dried. The variation in these parameters significantly affects the overall performance...... for the most common designs of solar dryers and the related practices used in the measurement, evaluation, and description of overall performance, including a variety of food product dried in scientific investigations....

  10. Thermally-Induced Structural Disturbances of Rigid Panel Solar Arrays

    Science.gov (United States)

    Johnston, John D.; Thornton, Earl A.

    1997-01-01

    The performance of a significant number of spacecraft has been impacted negatively by attitude disturbances resulting from thermally-induced motions of flexible structures. Recent examples of spacecraft affected by these disturbances include the Hubble Space Telescope (HST) and the Upper Atmosphere Research Satellite (UARS). Thermally-induced structural disturbances occur as the result of rapid changes in thermal loading typically initiated as a satellite exits or enters the Earth's shadow. Temperature differences in flexible appendages give rise to structural deformations, which in turn result in disturbance torques reacting back on the spacecraft. Structures which have proven susceptible to these disturbances include deployable booms and solar arrays. This paper investigates disturbances resulting from thermally-induced deformations of rigid panel solar arrays. An analytical model for the thermal-structural response of the solar array and the corresponding disturbance torque are presented. The effect of these disturbances on the attitude dynamics of a simple spacecraft is then investigated using a coupled system of governing equations which includes the effects of thermally-induced deformations. Numerical results demonstrate the effect of varying solar array geometry on the dynamic response of the system.

  11. Residential Solar-Based Seasonal Thermal Storage Systems in Cold Climates: Building Envelope and Thermal Storage

    OpenAIRE

    Alexandre Hugo; Radu Zmeureanu

    2012-01-01

    The reduction of electricity use for heating and domestic hot water in cold climates can be achieved by: (1) reducing the heating loads through the improvement of the thermal performance of house envelopes, and (2) using solar energy through a residential solar-based thermal storage system. First, this paper presents the life cycle energy and cost analysis of a typical one-storey detached house, located in Montreal, Canada. Simulation of annual energy use is performed using the TRNSYS softwar...

  12. Thermal performance of evacuated tube heat pipe solar collector

    Science.gov (United States)

    Putra, Nandy; Kristian, M. R.; David, R.; Haliansyah, K.; Ariantara, Bambang

    2016-06-01

    The high fossil energy consumption not only causes the scarcity of energy but also raises problems of global warming. Increasing needs of fossil fuel could be reduced through the utilization of solar energy by using solar collectors. Indonesia has the abundant potential for solar energy, but non-renewable energy sources still dominate energy consumption. With heat pipe as passive heat transfer device, evacuated tube solar collector is expected to heat up water for industrial and home usage without external power supply needed to circulate water inside the solar collector. This research was conducted to determine the performance of heat pipe-based evacuated tube solar collector as solar water heater experimentally. The experiments were carried out using stainless steel screen mesh as a wick material, and water and Al2O3-water 0.1% nanofluid as working fluid, and applying inclination angles of 0°, 15°, 30°, and 45°. To analyze the heat absorbed and transferred by the prototype, water at 30°C was circulated through the condenser. A 150 Watt halogen lamp was used as sun simulator, and the prototype was covered by an insulation box to obtain a steady state condition with a minimum affection of ambient changes. Experimental results show that the usage of Al2O3-water 0.1% nanofluid at 30° inclination angle provides the highest thermal performance, which gives efficiency as high as 0.196 and thermal resistance as low as 5.32 °C/W. The use of nanofluid as working fluid enhances thermal performance due to high thermal conductivity of the working fluid. The increase of the inclination angle plays a role in the drainage of the condensate to the evaporator that leads to higher thermal performance until the optimal inclination angle is reached.

  13. Barriers to the Diffusion of Solar Thermal Technologies

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Despite its considerable potential in household, domestic and industry sectors, the possible contribution of solar heat is often neglected in many academic and institutional energy projections and scenarios. This is best explained by the frequent failure to distinguish heat and work as two different forms of energy transfers. As a result, policy makers in many countries or States have tended to pay lesser attention to solar thermal technologies than to other renewable energy technologies.

  14. Concentrated Solar Power Gas Turbine Hybrid with Thermal Storage

    OpenAIRE

    Wallentinsen, Bård Sve

    2016-01-01

    Concentrated Solar Power (CSP) technology and shows promise for large-scale renewable electric power generation. CSP is suitable for development in conjunction with other technologies, and this thesis examines the combination of CSP technology with natural gas turbines in order to boost operating temperatures and efficiencies in a resulting solar hybrid gas turbine (SHGT) power plant. Thermal energy storage and a bottoming cycle are included in the design to increase both performance and rene...

  15. High Performance Flat Plate Solar Thermal Collector Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Rockenbaugh, Caleb [National Renewable Energy Lab. (NREL), Golden, CO (United States); Dean, Jesse [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lovullo, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Lisell, Lars [National Renewable Energy Lab. (NREL), Golden, CO (United States); Barker, Greg [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hanckock, Ed [National Renewable Energy Lab. (NREL), Golden, CO (United States); Norton, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-09-01

    This report was prepared for the General Services Administration by the National Renewable Energy Laboratory. The Honeycomb Solar Thermal Collector (HSTC) is a flat plate solar thermal collector that shows promising high efficiencies over a wide range of climate zones. The technical objectives of this study are to: 1) verify collector performance, 2) compare that performance to other market-available collectors, 3) verify overheat protection, and 4) analyze the economic performance of the HSTC both at the demonstration sites and across a matrix of climate zones and utility markets.

  16. The Future of the European Electricity Grid Is Bright: Cost Minimizing Optimization Shows Solar with Storage as Dominant Technologies to Meet European Emissions Targets to 2050

    Directory of Open Access Journals (Sweden)

    Zack Norwood

    2017-12-01

    Full Text Available The European roadmap for the power sector dictates an 80–95% cut of existing levels of carbon dioxide emissions is needed by the year 2050 to meet climate goals. This article describes results from a linear cost optimization investment model, ELIN, coupled with a solar technology model, Distributed Concentrating Solar Combined Heat and Power (DCS-CHP, using published investment costs for a comprehensive suite of renewable and conventional electricity generation technologies, to compare possible scenarios for the future electricity grid. The results of these model runs and sensitivity analyses indicate that: (1 solar photovoltaics (PV with battery storage will likely play a very large role in meeting European targets; (2 concentrating solar power (CSP with thermal energy storage is at a slight economic disadvantage with respect to PV to compete economically; (3 the economic potential of wind power is only comparable with solar PV if high wind penetration levels are allowed in the best wind sites in Europe; and (4 carbon capture and nuclear technologies are unlikely to compete economically with renewable technologies in creating a low-carbon future grid.

  17. Thermal Performance of a Large Low Flow Solar Heating System with a Highly Thermally Stratified Tank

    DEFF Research Database (Denmark)

    Furbo, Simon; Vejen, Niels Kristian; Shah, Louise Jivan

    2005-01-01

    is performing well in spite of the fact that the solar collectors are far from being orientated optimally. The utilization of the solar radiation on the collectors is higher, 46% in the second year of operation, than for any other system earlier investigated in Denmark, 16%-34%. The reason for the good thermal...... performance and for the excellent utilization of the solar radiation is the high hot-water consumption and the good system design making use of external heat exchangers and stratification inlet pipes.......In year 2000 a 336 m² solar domestic hot water system was built in Sundparken, Elsinore, Denmark. The solar heating system is a low flow system with a 10000 l hot-water tank. Due to the orientation of the buildings half of the solar collectors are facing east, half of the solar collectors...

  18. Semiconductor-based Multilayer Selective Solar Absorber for Unconcentrated Solar Thermal Energy Conversion.

    Science.gov (United States)

    Thomas, Nathan H; Chen, Zhen; Fan, Shanhui; Minnich, Austin J

    2017-07-13

    Solar thermal energy conversion has attracted substantial renewed interest due to its applications in industrial heating, air conditioning, and electricity generation. Achieving stagnation temperatures exceeding 200 °C, pertinent to these technologies, with unconcentrated sunlight requires spectrally selective absorbers with exceptionally low emissivity in the thermal wavelength range and high visible absorptivity for the solar spectrum. In this Communication, we report a semiconductor-based multilayer selective absorber that exploits the sharp drop in optical absorption at the bandgap energy to achieve a measured absorptance of 76% at solar wavelengths and a low emittance of approximately 5% at thermal wavelengths. In field tests, we obtain a peak temperature of 225 °C, comparable to that achieved with state-of-the-art selective surfaces. With straightforward optimization to improve solar absorption, our work shows the potential for unconcentrated solar thermal systems to reach stagnation temperatures exceeding 300 °C, thereby eliminating the need for solar concentrators for mid-temperature solar applications such as supplying process heat.

  19. From Molecular Electronics to Solar Thermal Energy Storage

    DEFF Research Database (Denmark)

    Olsen, Stine Tetzschner

    The Sun's signicant resource potential provides a solution for the world's increasing energy demand in a sustainable and responsible manner. However, the intrinsic property of the on-o cycles of the solar irradiation, i.e. daynight, sunny-cloudy, and summer-winter, constitutes a signicant challenge...... for the utilization of solar energy. An eective technology for storing the solar energy is required. This thesis focuses on solar thermal energy storage in molecules, since it oers a very compact and eective storage method. The rst chapter after the introduction of the thesis, chapter two, introduces the fundamental...... properties of the molecule, i.e. the electronic behaviour of the molecule in dierent environments, which is a key property for investigations of solar energy storage. The main focus of the research is on the electron transport in the Coulomb blockade regime. The third chapter goes into the challenge...

  20. Model predictive control of a solar-thermal reactor

    Science.gov (United States)

    Saade Saade, Maria Elizabeth

    Solar-thermal reactors represent a promising alternative to fossil fuels because they can harvest solar energy and transform it into storable and transportable fuels. The operation of solar-thermal reactors is restricted by the available sunlight and its inherently transient behavior, which affects the performance of the reactors and limits their efficiency. Before solar-thermal reactors can become commercially viable, they need to be able to maintain a continuous high-performance operation, even in the presence of passing clouds. A well-designed control system can preserve product quality and maintain stable product compositions, resulting in a more efficient and cost-effective operation, which can ultimately lead to scale-up and commercialization of solar thermochemical technologies. In this work, we propose a model predictive control (MPC) system for a solar-thermal reactor for the steam-gasification of biomass. The proposed controller aims at rejecting the disturbances in solar irradiation caused by the presence of clouds. A first-principles dynamic model of the process was developed. The model was used to study the dynamic responses of the process variables and to identify a linear time-invariant model used in the MPC algorithm. To provide an estimation of the disturbances for the control algorithm, a one-minute-ahead direct normal irradiance (DNI) predictor was developed. The proposed predictor utilizes information obtained through the analysis of sky images, in combination with current atmospheric measurements, to produce the DNI forecast. In the end, a robust controller was designed capable of rejecting disturbances within the operating region. Extensive simulation experiments showed that the controller outperforms a finely-tuned multi-loop feedback control strategy. The results obtained suggest that our controller is suitable for practical implementation.

  1. Thermal solar energy in Spain. State of the art and objectives; Energie solaire thermique en Espagne. Etat actuel et objectifs

    Energy Technology Data Exchange (ETDEWEB)

    Glenn, Jaouen

    2006-07-01

    According the Kyoto protocol, Spain has to reduce its CO{sub 2} emissions at 330 millions of tons (a decrease of 18 % from the level of 2003). From the european commission policy, the energy resources will be of 12 % of renewable energies. In this context, Spain developed an energy policy in favor of the solar energy. This document provides information on: the energy market in Spain, the thermal solar energy operating, the CO{sub 2} emissions, the state of the art in the domain in spain, the 2010 objectives, the programs and the assistance, some data on the solar market in comparison with the Europe. (A.L.B.)

  2. Simple Continuous-Flow Device for Combined Solar Thermal Pasteurization and Solar Disinfection for Water Sterilization

    Directory of Open Access Journals (Sweden)

    Anthony Amsberry

    2015-02-01

    Full Text Available A collection unit and reflective concentrators were used to thermally preheat water to at least 70 °C for thermal pasteurization prior to a solar disinfection stage. The device is offered as a novel combined cycle to be used for either solar thermal pasteurization, during seasonalpeaks in solar irradiation, or as a solar preheat for UV solar disinfection which would occur in a flow-through solar disinfection trough. Inexpensive materials were used in order to simulate in field functionality and applicability to rural regions with low solar input. Solar incidence at Oregon State University, with latitude 45.5°, was recorded during trials conducted during May 1 to June 10 for the purpose of directly scaling the water treatment volumetric flowrate of the device for any future tests in other locations. This scaling by solar irradiation makes this dataset useful for other locations with higher or lower solar input and needing more or less treated water. The simple gravity-fed continuous system presented in this article makes use of a large cold water reservoir, a shell-and-tube heat exchanger, and a solar collector. The system, operating at flowrates of 100-150 mL/min is able to reach outlet temperatures of 74°C.  The system is projected to produce 55 L of purified water daily when operating on a sunny day with peak UV radiation above 700 W/m2. System cost was $55 with an added optional $15 for the shell-and-tube heat exchanger.

  3. European sail tower SPS [Solar Power Satellite] concept

    Energy Technology Data Exchange (ETDEWEB)

    Seboldt, W.; Leipold, M.; Hanowski, N. [Institute of Space Sensor Technology and Planetary Exploration, Cologne (Germany). German Aerospace Center; Klimke, M. [HOPE Worldwide Deutschland, Berlin (Germany)

    2001-06-01

    Based on a DLR-study in 1998/99 on behalf of ESA/ESTEC called ''System Concepts, Architectures and Technologies for Space Exploration and Utilization (SE and U)'' a new design for an Earth-orbiting Solar Power Satellite (SPS) has been developed. The design is called ''European Sail Tower SPS'' and consists mainly of deplorable sail-like structures derived from the ongoing DLR/ESA solar sail technology development activity. Such an SPS satellite features an extremely light-weight and large tower-like orbital system and could supply Europe with significant amounts of electrical power generated by photovoltaic cells and subsequently transmitted to earth via microwaves. In order to build up the sail tower, 60 units - each consisting of a pair of square-shaped sails - are moved from LEO to GEO with electric propulsion and successively assembled in GEO robotically on a central strut. Each single sail has dimensions of 150 m x 150 m and is automatically deployed, using four diagonal lightweight carbon fiber (CFRP) booms which are initially rolled up on a central hub. The electric thrusters for the transport to GEO could also be used for orbit and attitude control of the assembled tower which has a total length of about 15 km and would be mainly gravity gradient stabilized. Employing thin film solar cell technology, each sail is used as a solar array and produces an electric power in orbit of about 3.7 MW{sub e}. A microwave antenna with a diameter of 1 km transmits the power to a 10 km rectenna on the ground. The total mass of this 450 MW SPS is about 2100 tons. First estimates indicate that the costs for one kWh delivered in this way could compete with present day energy costs, if launch costs would decrease by two orders of magnitude. Furthermore, mass production and large numbers of installed SPS systems must be assumed in order to lower significantly the production costs and to reduce the influence of the expensive technology

  4. Opportunities of solar thermal energy in the industry; Oportunidades de la energia solar termica en la industria

    Energy Technology Data Exchange (ETDEWEB)

    Perches salokangas, J.

    2004-07-01

    The industrial sector means a clear opportunity for the introduction of the solar thermal energy, as the economics, energy and CO2 avoided emissions savings potential is huge. Up to now, the use of solar thermal energy in the industrial sector has not yet been developed because of different technological and economical reasons have interfered in it development. The new solar thermal technologies developed by SOLEL for pure industrial applications, the new flat high efficiency collector SUNPRO, and the solar trough collector IND 300, allow the development of this promising and potential market for the solar thermal energy. (Author)

  5. Mir Cooperative Solar Array Project Accelerated Life Thermal Cycling Test

    Science.gov (United States)

    Hoffman, David J.; Scheiman, David A.

    1996-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint U.S./Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA will be used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station. The MCSA was brought to Mir by space shuttle Atlantis in November 1995. This report describes an accelerated thermal life cycle test which was performed on two samples of the MCSA. In eight months time, two MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles. There was no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early and removed from consideration. The nature of the performance degradation caused by this one cell is briefly discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the U.S. solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit). This was considered a successful development test.

  6. Mathematical model for thermal solar collectors by using magnetohydrodynamic Maxwell nanofluid with slip conditions, thermal radiation and variable thermal conductivity

    Science.gov (United States)

    Mahmood, Asif; Aziz, Asim; Jamshed, Wasim; Hussain, Sajid

    Solar energy is the cleanest, renewable and most abundant source of energy available on earth. The main use of solar energy is to heat and cool buildings, heat water and to generate electricity. There are two types of solar energy collection system, the photovoltaic systems and the solar thermal collectors. The efficiency of any solar thermal system depend on the thermophysical properties of the operating fluids and the geometry/length of the system in which fluid is flowing. In the present research a simplified mathematical model for the solar thermal collectors is considered in the form of non-uniform unsteady stretching surface. The flow is induced by a non-uniform stretching of the porous sheet and the uniform magnetic field is applied in the transverse direction to the flow. The non-Newtonian Maxwell fluid model is utilized for the working fluid along with slip boundary conditions. Moreover the high temperature effect of thermal radiation and temperature dependent thermal conductivity are also included in the present model. The mathematical formulation is carried out through a boundary layer approach and the numerical computations are carried out for cu-water and TiO2 -water nanofluids. Results are presented for the velocity and temperature profiles as well as the skin friction coefficient and Nusselt number and the discussion is concluded on the effect of various governing parameters on the motion, temperature variation, velocity gradient and the rate of heat transfer at the boundary.

  7. Better Thermal Insulation in Solar-Array Laminators

    Science.gov (United States)

    Burger, D. R.; Knox, J. F.

    1984-01-01

    Glass marbles improve temperature control. Modified vacuum laminator for photovoltaic solar arrays includes thermal insulation made of conventional glass marbles. Marbles serve as insulation for temperature control of lamination process at cure temperatures as high as 350 degrees F. Used to replace original insulation made of asbestos cement.

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

    Energy Technology Data Exchange (ETDEWEB)

    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.

  9. Solar Program Assessment: Environmental Factors - Ocean Thermal Energy Conversion.

    Science.gov (United States)

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

    This report presents the environmental problems which may arise with the further development of Ocean Thermal Energy Conversion, one of the eight Federally-funded solar technologies. To provide a background for this environmental analysis, the history and basic concepts of the technology are reviewed, as are its economic and resource requirements.…

  10. Fuels and chemicals from biomass using solar thermal energy

    Science.gov (United States)

    Giori, G.; Leitheiser, R.; Wayman, M.

    1981-01-01

    The significant nearer term opportunities for the application of solar thermal energy to the manufacture of fuels and chemicals from biomass are summarized, with some comments on resource availability, market potential and economics. Consideration is given to the production of furfural from agricultural residues, and the role of furfural and its derivatives as a replacement for petrochemicals in the plastics industry.

  11. Application of nanomaterials in solar thermal energy storage

    Science.gov (United States)

    Shamshirgaran, Seyed Reza; Khalaji Assadi, Morteza; Viswanatha Sharma, Korada

    2017-12-01

    Solar thermal conversion technology harvests the sun's energy, rather than fossil fuels, to generate low-cost, low/zero-emission energy in the form of heating, cooling or electrical form for residential, commercial, and industrial sectors. The advent of nanofluids and nanocomposites or phase change materials, is a new field of study which is adapted to enhance the efficiency of solar collectors. The concepts of thermal energy storage technologies are investigated and the role of nanomaterials in energy conversion is discussed. This review revealed that although the exploitation of nanomaterials will boost the performance of solar collectors almost in all cases, this would be accompanied by certain challenges such as production cost, instability, agglomeration and erosion. Earlier studies have dealt with the enhancement of thermal conductivity and heat capacity; however, less attention has been given to the facing challenges. Moreover, no exact criteria can be found for the selection of appropriate nanomaterials and their properties for a specific application. In most research studies, the nanoparticles' material and properties have not been selected based on estimated values so that all the aspects of desired application could be considered simultaneously. The wide spread use of nanomaterials can lead to cost effective solutions as well. Therefore, it seems there should be a sense of techno-economic optimization in exploiting nanomaterials for solar thermal energy storage applications. The optimization should cover the key parameters, particularly nanoparticle type, size, loading and shape which depends on the sort of application and also dispersion technology.

  12. Numerical simulation of a high temperature thermal storage unit for solar gas turbine applications

    CSIR Research Space (South Africa)

    Klein, P

    2010-09-01

    Full Text Available The implementation of thermal storage systems allows concentrating solar power plants to generate predictable power delivery to the grid by mitigating the variability of solar energy supply. However, while thermal storage solutions exist for Rankine...

  13. Photovoltaic solar panel for a hybrid PV/thermal system

    Energy Technology Data Exchange (ETDEWEB)

    Zakharchenko, R.; Licea-Jimenez, L.; Perez-Garcia, S.A.; Perez-Robles, J.F.; Gonzalez-Hernandez, J.; Vorobiev, Y. [CINVESTAV-Queretaro, (Mexico); Vorobiev, P. [Universidad Autonoma de Queretaro, (Mexico). Facultad de Ingenieria; Dehesa-Carrasco, U. [Instituto Tec. Del Istmo, Oaxaco (Mexico). Dep. de Ingenieria Electromecanica

    2004-05-01

    The hybrid PV-thermal system was studied, with the photovoltaic panel (PVP) area much smaller than that of the solar collector. Performance of the different panels in the system was investigated, in particular, those made of crystalline (c-) Si, {alpha}-Si and CuInSe{sub 2} as well as different materials and constructions for the thermal contact between the panel and the collector. Our conclusion is that the PVP for application in a hybrid system needs a special design providing efficient heat extraction from it. PVP was designed and made. Its study has shown that this design provides the high electrical and thermal efficiency of the hybrid system. (author)

  14. Solar thermal application for the livestock industry in Taiwan

    Directory of Open Access Journals (Sweden)

    Yi-Mei Liu

    2015-09-01

    Full Text Available Solar water heating systems have proven reliable and economical. In Taiwan, the cumulative area of installed solar collectors at the end of 2014 was approximately 2.39 million m2 and approximately 98% of those systems were installed in the domestic sector. Preheating water for livestock processing plants is cost-effective since heated water can be used for evisceration, sanitation during processing and for daily cleanup of plant. In this case study, detailed measurements are reported for parallel combined solar thermal and heat pump systems that are installed in a livestock processing plant. These results confirm that the hot water consumption, the mass flow rate and the operation of circulation and heat pumps affect the system's thermal efficiency. The combined operational effect is a factor in system design. The estimated payback period is less than the expected service period of the system, which validates the financial viability.

  15. Thermal advantage of tracking solar collectors under Danish weather conditions

    DEFF Research Database (Denmark)

    Andersen, Elsa; Dragsted, Janne; Furbo, Simon

    2010-01-01

    Theoretical investigations have been carried out with the aim to elucidate the thermal advantage of tracking solar collectors for different weather conditions in Kgs. Lyngby, Denmark (55.8°N), and for the weather conditions in Sisimiut, Greenland (66.9°N), just north of the arctic circle....... The investigations are based on calculations with a newly developed program. Measured weather data from a solar radiation measurement station at Technical University of Denmark in Kgs. Lyngby Denmark in the period 1990 to 2002 and the Danish Design Reference Year, DRY data file are used in the investigations....... The weather data used for Sisimiut are based on a Test Reference Year, TRY weather data file. The thermal advantages of different tracking strategies is investigated for two flat plate solar collectors with different efficiencies, operated at different temperature levels. The investigations show...

  16. Small solar thermal electric power plants with early commercial potential

    Science.gov (United States)

    Jones, H. E.; Bisantz, D. J.; Clayton, R. N.; Heiges, H. H.; Ku, A. C.

    1979-01-01

    Cost-effective small solar thermal electric power plants (1- to 10-MW nominal size) offer an attractive way of helping the world meet its future energy needs. The paper describes the characteristics of a conceptual near-term plant (about 1 MW) and a potential 1990 commercial version. The basic system concept is one in which steam is generated using two-axis tracking, parabolic dish, and point-focusing collectors. The steam is transported through low-loss piping to a central steam turbine generator unit where it is converted to electricity. The plants have no energy storage and their output power level varies with the solar insolation level. This system concept, which is firmly based on state-of-the-art technology, is projected to offer one of the fastest paths for U.S. commercialization of solar thermal electric power plants through moderate technology advances and mass production.

  17. Buffer thermal energy storage for an air Brayton solar engine

    Science.gov (United States)

    Strumpf, H. J.; Barr, K. P.

    1981-01-01

    The application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine was studied. To demonstrate the effect of buffer thermal energy storage on engine operation, a computer program was written which models the recuperator, receiver, and thermal storage device as finite-element thermal masses. Actual operating or predicted performance data are used for all components, including the rotating equipment. Based on insolation input and a specified control scheme, the program predicts the Brayton engine operation, including flows, temperatures, and pressures for the various components, along with the engine output power. An economic parametric study indicates that the economic viability of buffer thermal energy storage is largely a function of the achievable engine life.

  18. MINICHANNEL-TUBE SOLAR THERMAL COLLECTORS FOR LOW TO MEDIUM TEMPERATURE APPLICATIONS

    OpenAIRE

    Duong, Thuc

    2015-01-01

    Novel minichannel-tube solar thermal collectors for low to medium temperature applications are introduced. Two types of minichannel solar thermal collectors are analyzed experimentally: aluminum minichannel solar collector for low temperature applications, and copper minichannel solar collector for low to medium temperature applications.The aluminum minichannel solar collector has been tested for over a year alongside a conventional copper flat-plate solar collector of similar dimensions as t...

  19. Techno-Economic Assessment of Heat Transfer Fluid Buffering for Thermal Energy Storage in the Solar Field of Parabolic Trough Solar Thermal Power Plants

    Directory of Open Access Journals (Sweden)

    Jorge M. Llamas

    2017-08-01

    Full Text Available Currently, operating parabolic trough (PT solar thermal power plants, either solar-only or with thermal storage block, use the solar field as a heat transfer fluid (HTF thermal storage system to provide extra thermal capacity when it is needed. This is done by circulating heat transfer fluid into the solar field piping in order to create a heat fluid buffer. In the same way, by oversizing the solar field, it can work as an alternative thermal energy storage (TES system to the traditionally applied methods. This paper presents a solar field TES model for a standard solar field from a 50-MWe solar power plant. An oversized solar model is analyzed to increase the capacity storage system (HTF buffering. A mathematical model has been developed and different simulations have been carried out over a cycle of one year with six different solar multiples considered to represent the different oversized solar field configurations. Annual electricity generation and levelized cost of energy (LCOE are calculated to find the solar multiple (SM which makes the highest solar field thermal storage capacity possible within the minimum LCOE.

  20. Thermal design of spacecraft solar arrays using a polyimide foam

    Science.gov (United States)

    Bianco, N.; Iasiello, M.; Naso, V.

    2015-11-01

    The design of the Thermal Control System (TCS) of spacecraft solar arrays plays a fundamental role. Indeed, the spacecraft components must operate within a certain range of temperature. If this doesn't occur, their performance is reduced and they may even break. Solar arrays, which are employed to recharge batteries, are directly exposed to the solar heat flux, and they need to be insulated from the earth's surface irradiation. Insulation is currently provided either with a white paint coating or with a Multi Layer Insulation (MLI) system [1]. A configuration based on an open-cell polyimide foam has also been recently proposed [2]. Using polyimide foams in TCSs looks very attractive in terms of costs, weight and assembling. An innovative thermal analysis of the above cited TCS configurations is carried out in this paper, by solving the porous media energy equation, under the assumption of Local Thermal Equilibrium (LTE) between the two phases. Radiation effects through the solar array are also considered by using the Rosseland approximation. Under a stationary daylight condition, temperature profiles are obtained by means of the finite-element based code COMSOL Multiphysics®. Finally, since the weight plays an important role in aerospace applications, weights of the three TCS configurations are compared.

  1. Design Considerations for Space Transfer Vehicles Using Solar Thermal Propulsion

    Science.gov (United States)

    Emrich, William J.

    1995-01-01

    The economical deployment of satellites to high energy earth orbits is crucial to the ultimate success of this nations commerical space ventures and is highly desirable for deep space planetary missions requiring earth escape trajectories. Upper stage space transfer vehicles needed to accomplish this task should ideally be simple, robust, and highly efficient. In this regard, solar thermal propulsion is particularly well suited to those missions where high thrust is not a requirement. The Marshall Space Flight Center is , therefore, currently engaged in defining a transfer vehicle employing solar thermal propulsion capable of transferring a 1000 lb. payload from low Earth orbit (LEO) to a geostationary Earth orbit (GEO) using a Lockheed launch vehicle (LLV3) with three Castors and a large shroud. The current design uses liquid hydrogen as the propellant and employs two inflatable 16 x 24 feet eliptical off-axis parabolic solar collectors to focus sunlight onto a tungsten/rhenium windowless black body type absorber. The concentration factor on this design is projected to be approximately 1800:1 for the primary collector and 2.42:1 for the secondary collector for an overall concentration factor of nearly 4400:1. The engine, which is about twice as efficient as the best currently available chemical engines, produces two pounds of thrust with a specific impulse (Isp) of 860 sec. Transfer times to GEO are projected to be on the order of one month. The launch and deployed configurations of the solar thermal upper stage (STUS) are depicted.

  2. Solar Power Satellite Thermal Control Approach

    Science.gov (United States)

    Sacchi, E.; Cassisa, G.; Gottero, M.

    2004-12-01

    The concept of generating solar power in space and transmitting it to earth or any other desired destination such as a planet, moon, or to charge a space vehicle via microwaves, stems from a wide variety of human needs and necessities. It is now a well-known fact that world population increases at a very rapid rate, nearly 80 millions or more per year, and the world-wide energy demand seems to double in the course of the present century. If technology has to advance at the present rate, in phase with high living standards, energy growth must not lag behind. These estimates are based on the population growth rate in the developing countries and the simultaneous increase in per capita energy consumption in these countries, coupled with economical boost. In most of the underdeveloped countries energy needs are of small scales, faraway from the power distribution line and can be very easily satisfied by harnessing solar energy. Furthermore, the Earth temperature has increased by 0.5° to 1° F during the past century. This rise in temperature is believed to have been caused by the use of oil, coal, and natural gas (fossil fuels) for transportation and energy production. Actually, fossil fuel combustion-based power plants are the dominant sources for energy demands. Therefore, increased power production will accelerate the production of greenhouse gases (predominantly CO2). To cope with their energy needs, countries could be engaged in the use of nuclear energy, which could accelerate the diffusion of nuclear arms as a bye- product.

  3. Hybrid Solar: A Review on Photovoltaic and Thermal Power Integration

    Directory of Open Access Journals (Sweden)

    T. T. Chow

    2012-01-01

    Full Text Available The market of solar thermal and photovoltaic electricity generation is growing rapidly. New ideas on hybrid solar technology evolve for a wide range of applications, such as in buildings, processing plants, and agriculture. In the building sector in particular, the limited building space for the accommodation of solar devices has driven a demand on the use of hybrid solar technology for the multigeneration of active power and/or passive solar devices. The importance is escalating with the worldwide trend on the development of low-carbon/zero-energy buildings. Hybrid photovoltaic/thermal (PVT collector systems had been studied theoretically, numerically, and experimentally in depth in the past decades. Together with alternative means, a range of innovative products and systems has been put forward. The final success of the integrative technologies relies on the coexistence of robust product design/construction and reliable system operation/maintenance in the long run to satisfy the user needs. This paper gives a broad review on the published academic works, with an emphasis placed on the research and development activities in the last decade.

  4. A performance analysis of solar chimney thermal power systems

    Directory of Open Access Journals (Sweden)

    Al-Dabbas Awwad Mohammed

    2011-01-01

    Full Text Available The objective of this study was to evaluate the solar chimney performance theoretically (techno-economic. A mathematical model was developed to estimate the following parameter: Power output, Pressure drop across the turbine, the max chimney height, Airflow temperature, and the overall efficiency of solar chimney. The mathematical model was validated with experimental data from the prototype in Manzanares power. It can be concluded that the differential pressure of collector-chimney transition section in the system, is increase with the increase of solar radiation intensity. The specific system costs are between 2000 Eur/kW and 5000 Eur/kW depending on the system size, system concept and storage size. Hence, a 50 MWe solar thermal power plant will cost 100-250 Eur million. At very good sites, today’s solar thermal power plants can generate electricity in the range of 0.15 Eur/kWh, and series production could soon bring down these costs below 0.10 Eur /kWh.

  5. Thermal Cycling of Mir Cooperative Solar Array (MCSA) Test Panels

    Science.gov (United States)

    Hoffman, David J.; Scheiman, David A.

    1997-01-01

    The Mir Cooperative Solar Array (MCSA) project was a joint US/Russian effort to build a photovoltaic (PV) solar array and deliver it to the Russian space station Mir. The MCSA is currently being used to increase the electrical power on Mir and provide PV array performance data in support of Phase 1 of the International Space Station (ISS), which will use arrays based on the same solar cells used in the MCSA. The US supplied the photovoltaic power modules (PPMs) and provided technical and programmatic oversight while Russia provided the array support structures and deployment mechanism and built and tested the array. In order to ensure that there would be no problems with the interface between US and Russian hardware, an accelerated thermal life cycle test was performed at NASA Lewis Research Center on two representative samples of the MCSA. Over an eight-month period (August 1994 - March 1995), two 15-cell MCSA solar array 'mini' panel test articles were simultaneously put through 24,000 thermal cycles (+80 C to -100 C), equivalent to four years on-orbit. The test objectives, facility, procedure and results are described in this paper. Post-test inspection and evaluation revealed no significant degradation in the structural integrity of the test articles and no electrical degradation, not including one cell damaged early as an artifact of the test and removed from consideration. The interesting nature of the performance degradation caused by this one cell, which only occurred at elevated temperatures, is discussed. As a result of this test, changes were made to improve some aspects of the solar cell coupon-to-support frame interface on the flight unit. It was concluded from the results that the integration of the US solar cell modules with the Russian support structure would be able to withstand at least 24,000 thermal cycles (4 years on-orbit).

  6. Numerical thermal back-calculation of the Kerava Solar Village underground thermal energy storage

    OpenAIRE

    Oosterbaan, Harm; Janiszewski, Mateusz; Uotinen, Lauri; Siren, Topias; Rinne, Mikael

    2017-01-01

    With increasing pressure to reduce the fraction of energy coming from fossil fuels, there is an increased need for research into feasible, and sustainable energy sources, such as solar energy. The problem with solar energy is the mismatch between supply and demand, and so the energy needs to be stored. This research paper is a part of the project titled “Tackling the Challenges of a Solar-Community Concept in High Latitudes”, and aims in helping to design a thermal energy storage system for s...

  7. Solar photovoltaic/thermal residential experiment. Phase I. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Darkazalli, G.

    1980-07-01

    Month-by-month energy transfer data between an occupied residence and its energy supply systems are presented. The data were obtained during the first phase of photovoltaic/thermal residential research conducted at the University of Texas at Arlington/Solar Energy Research Facility. This research was part of the US Department of Energy Photovoltaic/Thermal Project managed by the M.I.T. Lincoln Laboratory. Energy transfer data are divided into different categories depending on how the energy is consumed. Energy transfers between some system components are also categorized. These components include a flat-plate thermal collector array, a flat-plate photovoltaic array, a dc-to-ac inverter, thermal storage tanks, and a series heat pump. System operations included directing surplus electrical energy (generated by the photovoltaic array) into the local utility grid. The heat pump used off-peak utility power to chill water during the cooling season.

  8. Metal hydrides for concentrating solar thermal power energy storage

    Science.gov (United States)

    Sheppard, D. A.; Paskevicius, M.; Humphries, T. D.; Felderhoff, M.; Capurso, G.; Bellosta von Colbe, J.; Dornheim, M.; Klassen, T.; Ward, P. A.; Teprovich, J. A.; Corgnale, C.; Zidan, R.; Grant, D. M.; Buckley, C. E.

    2016-04-01

    The development of alternative methods for thermal energy storage is important for improving the efficiency and decreasing the cost of concentrating solar thermal power. We focus on the underlying technology that allows metal hydrides to function as thermal energy storage (TES) systems and highlight the current state-of-the-art materials that can operate at temperatures as low as room temperature and as high as 1100 °C. The potential of metal hydrides for thermal storage is explored, while current knowledge gaps about hydride properties, such as hydride thermodynamics, intrinsic kinetics and cyclic stability, are identified. The engineering challenges associated with utilising metal hydrides for high-temperature TES are also addressed.

  9. Solar Probe Plus MAG Sensor Thermal Design for Low Heater Power and Extreme Thermal Environment

    Science.gov (United States)

    Choi, Michael K.

    2015-01-01

    The heater power available for the Solar Probe Plus FIELDS MAG sensor is less than half of the heritage value for other missions. Nominally the MAG sensors are in the spacecraft's umbra. In the worst hot case, approximately 200 spacecraft communication downlinks, up to 10 hours each, are required at 0.7 AU. These downlinks require the spacecraft to slew 45 deg. about the Y-axis, exposing the MAG sensors and boom to sunlight. This paper presents the thermal design to meet the MAG sensor thermal requirements in the extreme thermal environment and with low heater power. A thermal balance test on the MAG sensor engineering model has verified the thermal design and correlated the thermal model for flight temperature predictions.

  10. Novel Thermal Storage Technologies for Concentrating Solar Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Neti, Sudhakar [Lehigh Univ., Bethlehem, PA (United States). Mechanical Engineering and Mechanics; Oztekin, Alparslan [Lehigh Univ., Bethlehem, PA (United States); Chen, John [Lehigh Univ., Bethlehem, PA (United States); Tuzla, Kemal [Lehigh Univ., Bethlehem, PA (United States); Misiolek, Wojciech [Lehigh Univ., Bethlehem, PA (United States)

    2013-06-20

    The technologies that are to be developed in this work will enable storage of thermal energy in 100 MWe solar energy plants for 6-24 hours at temperatures around 300°C and 850°C using encapsulated phase change materials (EPCM). Several encapsulated phase change materials have been identified, fabricated and proven with calorimetry. Two of these materials have been tested in an airflow experiment. A cost analysis for these thermal energy storage systems has also been conducted that met the targets established at the initiation of the project.

  11. Rapid thermal sintering of the metallizations of silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Laugier, A.; El Omari, H.; Boyeaux, J.P. [Institut National des Sciences Appliquees de Lyon, Villeurbanne (France). Lab. de Physique de la Matiere; Hartiti, B.; Muller, J.C. [CNRS, Strasbourg (France). Lab. de Physique et Applications des Semiconducteurs; Nam, L.Q.; Sarti, D. [Photowatt International S.A., Bourgoin Jallieu (France)

    1994-12-31

    Rapid Thermal Processing (RTP) using radiation from tungsten halogen lamps as a heat source is a very promising candidate to replace conventional furnace annealing as it offers many advantages such as a reduced overall thermal budget and a lower gas consumption. In this paper the authors show that with moderate temperature, RTP can be used to obtain screen printed contacts with low contacts resistivity and without degrading the transport properties of the solar cell base region. They investigate on Polix multicrystalline solar cells the possibility to replace the conventional sintering by a RTP annealing of the Ag front grid and of the back Al/Ag contact in a single step performed after the antireflection coating deposition.

  12. Thermal properties of carbon black aqueous nanofluids for solar absorption

    Directory of Open Access Journals (Sweden)

    Han Dongxiao

    2011-01-01

    Full Text Available Abstract In this article, carbon black nanofluids were prepared by dispersing the pretreated carbon black powder into distilled water. The size and morphology of the nanoparticles were explored. The photothermal properties, optical properties, rheological behaviors, and thermal conductivities of the nanofluids were also investigated. The results showed that the nanofluids of high-volume fraction had better photothermal properties. Both carbon black powder and nanofluids had good absorption in the whole wavelength ranging from 200 to 2,500 nm. The nanofluids exhibited a shear thinning behavior. The shear viscosity increased with the increasing volume fraction and decreased with the increasing temperature at the same shear rate. The thermal conductivity of carbon black nanofluids increased with the increase of volume fraction and temperature. Carbon black nanofluids had good absorption ability of solar energy and can effectively enhance the solar absorption efficiency.

  13. Irrigation market for solar thermal parabolic dish systems

    Science.gov (United States)

    Habib-Agahi, H.; Jones, S. C.

    1981-01-01

    The potential size of the onfarm-pumped irrigation market for solar thermal parabolic dish systems in seven high-insolation states is estimated. The study is restricted to the displacement of three specific fuels: gasoline, diesel and natural gas. The model was developed to estimate the optimal number of parabolic dish modules per farm based on the minimum cost mix of conventional and solar thermal energy required to meet irrigation needs. The study concludes that the potential market size for onfarm-pumped irrigation applications ranges from 101,000 modules when a 14 percent real discount rate is assumed to 220,000 modules when the real discount rate drops to 8 percent. Arizona, Kansas, Nebraska, New Mexico and Texas account for 98 percent of the total demand for this application, with the natural gas replacement market accounting for the largest segment (71 percent) of the total market.

  14. SolarOil Project, Phase I preliminary design report. [Solar Thermal Enhanced Oil Recovery project

    Energy Technology Data Exchange (ETDEWEB)

    Baccaglini, G.; Bass, J.; Neill, J.; Nicolayeff, V.; Openshaw, F.

    1980-03-01

    The preliminary design of the Solar Thermal Enhanced Oil Recovery (SolarOil) Plant is described in this document. This plant is designed to demonstrate that using solar thermal energy is technically feasible and economically viable in enhanced oil recovery (EOR). The SolarOil Plant uses the fixed mirror solar concentrator (FMSC) to heat high thermal capacity oil (MCS-2046) to 322/sup 0/C (611/sup 0/F). The hot fluid is pumped from a hot oil storage tank (20 min capacity) through a once-through steam generator which produces 4.8 MPa (700 psi) steam at 80% quality. The plant net output, averaged over 24 hr/day for 365 days/yr, is equivalent to that of a 2.4 MW (8.33 x 10/sup 6/ Btu/hr) oil-fired steam generator having an 86% availability. The net plant efficiency is 57.3% at equinox noon, a 30%/yr average. The plant will be demonstrated at an oilfield site near Oildale, California.

  15. Validation of TRNSYS model for solar thermal facility; Validacion de un modelo TRNSYS para una instalacion solar termica

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, G.; Macias, F. J.

    2004-07-01

    TRNSYS is a well-known tool to simulate solar systems. This paper is a summary of the validation process of a solar system TRNSYS model. An actual solar system, is modeled with standard TRNSYS components, the actual system is monitorized and the measures of consume, solar radiation, ambient temperature are used as inputs values for the TRNSYS model in order to compare the outputs of the simulations with the real values of the solar thermal installation. (Author)

  16. A solar air collector with integrated latent heat thermal storage

    Science.gov (United States)

    Charvat, Pavel; Ostry, Milan; Mauder, Tomas; Klimes, Lubomir

    2012-04-01

    Simulations of the behaviour of a solar air collector with integrated latent heat thermal storage were performed. The model of the collector was created with the use of coupling between TRNSYS 17 and MATLAB. Latent heat storage (Phase Change Material - PCM) was integrated with the solar absorber. The model of the latent heat storage absorber was created in MATLAB and the model of the solar air collector itself was created in TRNSYS with the use of TYPE 56. The model of the latent heat storage absorber allows specification of the PCM properties as well as other parameters. The simulated air collector was the front and back pass collector with the absorber in the middle of the air cavity. Two variants were considered for comparison; the light-weight absorber made of sheet metal and the heat-storage absorber with the PCM. Simulations were performed for the climatic conditions of the Czech Republic (using TMY weather data).

  17. Solar thermal plant impact analysis and requirements definition

    Science.gov (United States)

    Gupta, Y. P.

    1980-01-01

    Progress on a continuing study comprising of ten tasks directed at defining impact and requirements for solar thermal power systems (SPS), 1 to 10 MWe each in capacity, installed during 1985 through year 2000 in a utility or a nonutility load in the United States is summarized. The point focus distributed receiver (PFDR) solar power systems are emphasized. Tasks 1 through 4, completed to date, include the development of a comprehensive data base on SPS configurations, their performance, cost, availability, and potential applications; user loads, regional characteristics, and an analytic methodology that incorporates the generally accepted utility financial planning methods and several unique modifications to treat the significant and specific characteristics of solar power systems deployed in either central or distributed power generation modes, are discussed.

  18. Macroeconomic impact of the Solar Thermal Electricity Industry in Spain

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-10-15

    In the last three years, Solar Thermal Electricity (STE) in Spain has grown significantly. Its weight within the renewables mix is becoming relevant, and even more so, its impact on economics, society, the environment, and reducing energy dependence. This report was carried out by Deloitte for Protermosolar to quantitatively and qualitatively evaluate the main macroeconomic variables derived from the development of this technology in Spain from 2008 to 2010, and forecast its possible future impact.

  19. Second European symposium `Solar and electric-powered vehicles`. Proceedings; Zweites Europaeisches Symposium Solar- und Elektromobile. Vortraege

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    This book contains 30 scripts of the talks, which were given at the Second European symposium ``Solar and electric-powered vehicles``. For each of the 30 scripts a separate abstract has been written. The main emphasis of the symposium was on: Marginal conditions and an overview of the market; Aspects of the energy storage; Safety aspects; Comfort of solar and electric-powered vehicles. (HW) [Deutsch] Das vorliegende Buch enthaelt die 30 Manuskripte der Vortraege, die anlaesslich des zweiten europaeischen Symposiums `Solar- und Elektromobile` gehalten wurden. Fuer die 30 Manuskripte wurde eine gesonderte inhaltliche Erschliessung erarbeitet. Schwerpunkte der Tagung: - Rahmenbedingungen und Marktuebersicht; - Aspekte der Energiespeichers; - Sicherheitsfragen; - Komfort von Solar- und Elektromobilen. (HW)

  20. Exergetic analysis of parabolic trough solar thermal power plants

    Science.gov (United States)

    Petrakopoulou, F.; Ruperez, B.; San Miguel, G.

    2014-12-01

    A very important component to achieve sustainable development in the energy sector is the improvement of energy efficiency of widely applied thermodynamic processes. Evaluation and optimization methods of energy processes play a crucial role in fulfilling this goal. A suitable method for the evaluation and optimization of energy conversion systems has been proven to be the exergetic analysis. In this work, two parabolic trough solar thermal power plants are simulated in detail using commercial software, and they are further analysed and compared using an exergetic analysis. The first plant uses a thermal fluid to produce the steam required in a steam generator, while the second one produces the steam directly in the solar field. The analysis involves the evaluation of the individual components of the power plants, as well as the performance evaluation of the overall structures. The main goal is to detect thermodynamic inefficiencies of the two different configurations and propose measures to minimize those. We find that the two examined plants have similar main sources of exergy destruction: the solar field (parabolic trough solar collectors), followed by the steam generator. This reveals the importance of an optimal design of these particular components, which could reduce inefficiencies present in the system. The differences in the exergy destruction and exergetic efficiencies of individual components of the two plants are analyzed in detail based on comparable operational conditions.

  1. Solar Thermal Energy Storage in a Photochromic Macrocycle.

    Science.gov (United States)

    Vlasceanu, Alexandru; Broman, Søren L; Hansen, Anne S; Skov, Anders B; Cacciarini, Martina; Kadziola, Anders; Kjaergaard, Henrik G; Mikkelsen, Kurt V; Nielsen, Mogens Brøndsted

    2016-07-25

    The conversion and efficient storage of solar energy is recognized to hold significant potential with regard to future energy solutions. Molecular solar thermal batteries based on photochromic systems exemplify one possible technology able to harness and apply this potential. Herein is described the synthesis of a macrocycle based on a dimer of the dihydroazulene/vinylheptafulvene (DHA/VHF) photo/thermal couple. By taking advantage of conformational strain, this DHA-DHA macrocycle presents an improved ability to absorb and store incident light energy in chemical bonds (VHF-VHF). A stepwise energy release over two sequential ring-closing reactions (VHF→DHA) combines the advantages of an initially fast discharge, hypothetically addressing immediate energy consumption needs, followed by a slow process for consistent, long-term use. This exemplifies another step forward in the molecular engineering and design of functional organic materials towards solar thermal energy storage and release. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Thermal performance optimization of a flat plate solar air heater using genetic algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Varun; Siddhartha [Department of Mechanical Engineering, National Institute of Technology, Hamirpur 177 005 (H.P.) (India)

    2010-05-15

    Thermal performance of solar air heater is low and different techniques are adopted to increase the performance of solar air heaters, such as: fins, artificial roughness etc. In this paper an attempt has been done to optimize the thermal performance of flat plate solar air heater by considering the different system and operating parameters to obtain maximum thermal performance. Thermal performance is obtained for different Reynolds number, emissivity of the plate, tilt angle and number of glass plates by using genetic algorithm. (author)

  3. Thermal Analysis of a Solar Powered Absorption Cooling System with Fully Mixed Thermal Storage at Startup

    Directory of Open Access Journals (Sweden)

    Camelia Stanciu

    2017-01-01

    Full Text Available A simple effect one stage ammonia-water absorption cooling system fueled by solar energy is analyzed. The considered system is composed by a parabolic trough collector concentrating solar energy into a tubular receiver for heating water. This is stored in a fully mixed thermal storage tank and used in the vapor generator of the absorption cooling system. Time dependent cooling load is considered for the air conditioning of a residential two-storey house. A parametric study is performed to analyze the operation stability of the cooling system with respect to solar collector and storage tank dimensions. The results emphasized that there is a specific storage tank dimension associated to a specific solar collector dimension that could ensure the longest continuous startup operation of the cooling system when constant mass flow rates inside the system are assumed.

  4. High temperature latent heat thermal energy storage to augment solar thermal propulsion for microsatellites

    Science.gov (United States)

    Gilpin, Matthew R.

    Solar thermal propulsion (STP) offers an unique combination of thrust and efficiency, providing greater total DeltaV capability than chemical propulsion systems without the order of magnitude increase in total mission duration associated with electric propulsion. Despite an over 50 year development history, no STP spacecraft has flown to-date as both perceived and actual complexity have overshadowed the potential performance benefit in relation to conventional technologies. The trend in solar thermal research over the past two decades has been towards simplification and miniaturization to overcome this complexity barrier in an effort finally mount an in-flight test. A review of micro-propulsion technologies recently conducted by the Air Force Research Laboratory (AFRL) has identified solar thermal propulsion as a promising configuration for microsatellite missions requiring a substantial Delta V and recommended further study. A STP system provides performance which cannot be matched by conventional propulsion technologies in the context of the proposed microsatellite ''inspector" requiring rapid delivery of greater than 1500 m/s DeltaV. With this mission profile as the target, the development of an effective STP architecture goes beyond incremental improvements and enables a new class of microsatellite missions. Here, it is proposed that a bi-modal solar thermal propulsion system on a microsatellite platform can provide a greater than 50% increase in Delta V vs. chemical systems while maintaining delivery times measured in days. The realization of a microsatellite scale bi-modal STP system requires the integration of multiple new technologies, and with the exception of high performance thermal energy storage, the long history of STP development has provided "ready" solutions. For the target bi-modal STP microsatellite, sensible heat thermal energy storage is insufficient and the development of high temperature latent heat thermal energy storage is an enabling

  5. The influence of weather on the thermal performance of solar heating systems

    DEFF Research Database (Denmark)

    Andersen, Elsa; Furbo, Simon; Shah, Louise Jivan

    2003-01-01

    . The investigation is based on calculations with validated models. Solar heating systems with different solar collector types, heat storage volumes and solar fractions are included in the investigation. The yearly solar radiation varies with approximately 20 % in the period from 1990 until 2002. The calculations......The influence of weather on the thermal performance of solar combi systems, solar domestic hot water systems and solar heating plants is investigated. The investigation is based on weather data from the Danish Design Reference Year, DRY and weather data measured for a period from 1990 until 2002...... show that the thermal performance of the investigated systems varies due to the weather variation. The variation of the yearly thermal performance of a solar heating plant is about 40 % while the variation of the yearly thermal performance of a solar domestic hot water system is about 30...

  6. Thermal efficiency of low cost solar collectors - CSBC; Eficiencia termica de coletores solares de baixo custo - CSBC

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Renato C.; Shiota, Robson T.; Mello, Samuel F.; Assis Junior, Valdir; Bartoli, Julio R. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Faculdade de Engenharia Quimica. Dept. de Tecnologia de Polimeros

    2006-07-01

    The thermal performance of a low cost flat panel solar collector was measured. This Low Cost Solar Collector is a novel concept for water heating using only thermoplastics materials, used on building: ceiling and tubes made of unplasticized PVC, but without transparent cover. The top side of the UPVC panel was black painted to be the solar radiation absorber surface. Prototypes were installed on two charity houses around Campinas and at the FEQ campus, being used without any trouble for one year. The thermal efficiency analysis followed ABNT NBR 10184 standard at the Green-Solar Laboratory, Brazilian Centre for Development of Solar Thermal Energy, PUC-Minas. It was measured a thermal efficiency of 67%, compared to the 75% usually found on conventional solar collectors made of copper tubes and with glass cover. (author)

  7. Azobenzene-functionalized carbon nanotubes as high-energy density solar thermal fuels.

    Science.gov (United States)

    Kolpak, Alexie M; Grossman, Jeffrey C

    2011-08-10

    Solar thermal fuels, which reversibly store solar energy in molecular bonds, are a tantalizing prospect for clean, renewable, and transportable energy conversion/storage. However, large-scale adoption requires enhanced energy storage capacity and thermal stability. Here we present a novel solar thermal fuel, composed of azobenzene-functionalized carbon nanotubes, with the volumetric energy density of Li-ion batteries. Our work also demonstrates that the inclusion of nanoscale templates is an effective strategy for design of highly cyclable, thermally stable, and energy-dense solar thermal fuels.

  8. Solar thermal OTV - applications to reusable and expendable launch vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Kessler, Thomas L. [Boeing Co., Phantom Works (United States); Frye, Patrick [Boeing Co., Rocketdyne Propulsion and Power (United States); Partch, Russ [Air Force Research Lab. (United States)

    2000-11-01

    The Solar Orbit Transfer Vehicle (SOTV) program being sponsored by the U.S. Air Force Research Laboratory (AFRL) is developing technology that will engender revolutionary benefits to satellites and orbit-to-orbit transfer systems. Solar thermal propulsion offers significant advantages for near-term expendable launch vehicles (ELVs) such as Delta IV, mid- to far-term reusable launch vehicles (RLVs) and ultimately to manned exploration of the Moon and Mars. Solar thermal propulsion uses a relatively large mirrored concentrator to focus solar energy onto a compact absorber, which is in turn heated to >2200 K. This heat can then be used in two major ways. By flowing hydrogen or another working fluid through the absorber, high efficiency thrust can be generated with 800 sec or more specific impulse (Isp), almost twice that of conventional cryogenic stages and comparable with typical solid-core nuclear thermal stages. Within a decade, advances in materials and fabrication processes hold the promise of the Isp ranging up to 1,100 sec. In addition, attached thermionic or alkali metal thermoelectric converter (AMTEC) power converters can be used to generate 20 to 100 kilowatts (kW) of electricity. The SOTV Space Experiment (SOTV-SE), planned to be flown in 2003, will demonstrate both hydrogen propulsion and thermionic power generation, including advanced lightweight deployable concentrators suitable for large-scale applications. Evolutionary geosynchronous-transfer orbit/geosynchronous-Earth orbit (GTO/GEO) payload lift capability improvements of 50% or more to the Delta IV launch vehicles could be implemented as part of the Delta IV P4I plan shortly thereafter. Beyond that, SOTV technology should allow long-term storage of stages in orbits up to GEO with tremendous manoeuvring capability, potentially 4 to 5 km/sec or more. Servicing of low-Earth orbit (LEO) and GEO assets and reusable (ROTVs) are other possible applications. Offering a combination of high Isp and high

  9. Heat engine development for solar thermal power systems

    Science.gov (United States)

    Pham, H. Q.; Jaffe, L. D.

    1981-01-01

    The technical status of three heat engines (Stirling, high-temperature Brayton, and Combined cycle) for use in solar thermal power systems is presented. Performance goals necessary to develop a system competitive with conventional power requirements include an external heated engine output less than 40 kW, and efficiency power conversion subsystem at least 40% at rated output, and a half-power efficiency of at least 37%. Results show that the Stirling engine can offer a 39% efficiency with 100 hours of life, and a 20% efficiency with 10,000 hours of life, but problems with seals and heater heads exist. With a demonstrated efficiency near 31% at 1500 F and a minimum lifetime of 100,000 hours, the Brayton engine does not offer sufficient engine lifetime, efficiency, and maintenance for solar thermal power systems. Examination of the Rankine bottoming cycle of the Combined cycle engine reveals a 30 year lifetime, but a low efficiency. Additional development of engines for solar use is primarily in the areas of components to provide a long lifetime, high reliability, and low maintenance (no more than $0.001/kW-hr).

  10. Solar thermal plant of air tube for solar air conditioning; Planta Solar Termica de tubos de vacio para aire acondicionado solar

    Energy Technology Data Exchange (ETDEWEB)

    Bruno, J. C.; Lopez, J.; Coronas, A.

    2004-07-01

    The present implementation of refrigeration and air conditioning technologies driven by thermal solar energy is very limited although there is a great market demand for them for environmental reasons and security of energy supply. In this paper it is presented a detailed technical description of the solar plant installed at the technological Innovation Centre CREVER, and an example of a complete energy analysis of this plant working under the required conditions to be used for solar air conditioning applications. Also it is included a review of solar air conditioning systems state of the art. (Author)

  11. Multiscale computational modeling of a radiantly driven solar thermal collector

    Science.gov (United States)

    Ponnuru, Koushik

    The objectives of the master's thesis are to present, discuss and apply sequential multiscale modeling that combines analytical, numerical (finite element-based) and computational fluid dynamic (CFD) analysis to assist in the development of a radiantly driven macroscale solar thermal collector for energy harvesting. The solar thermal collector is a novel green energy system that converts solar energy to heat and utilizes dry air as a working heat transfer fluid (HTF). This energy system has important advantages over competitive technologies: it is self-contained (no energy sources are needed), there are no moving parts, no oil or supplementary fluids are needed and it is environmentally friendly since it is powered by solar radiation. This work focuses on the development of multi-physics and multiscale models for predicting the performance of the solar thermal collector. Model construction and validation is organized around three distinct and complementary levels. The first level involves an analytical analysis of the thermal transpiration phenomenon and models for predicting the associated mass flow pumping that occurs in an aerogel membrane in the presence of a large thermal gradient. Within the aerogel, a combination of convection, conduction and radiation occurs simultaneously in a domain where the pore size is comparable to the mean free path of the gas molecules. CFD modeling of thermal transpiration is not possible because all the available commercial CFD codes solve the Navier Stokes equations only for continuum flow, which is based on the assumption that the net molecular mass diffusion is zero. However, thermal transpiration occurs in a flow regime where a non-zero net molecular mass diffusion exists. Thus these effects are modeled by using Sharipov's [2] analytical expression for gas flow characterized by high Knudsen number. The second level uses a detailed CFD model solving Navier Stokes equations for momentum, heat and mass transfer in the various

  12. Experimental characterization of a solar cooker with thermal energy storage based on solar salt

    Science.gov (United States)

    Coccia, G.; Di Nicola, G.; Tomassetti, S.; Gabrielli, G.; Chieruzzi, M.; Pierantozzi, M.

    2017-11-01

    High temperature solar cooking allows to cook food fast and with good efficiency. An unavoidable drawback of this technology is that it requires nearly clear-sky conditions. In addition, evening cooking is difficult to be accomplished, particularly on the winter season during which solar radiation availability is limited to a few hours in the afternoon in most of countries. These restrictions could be overcome using a cooker thermal storage unit (TSU). In this work, a TSU based on solar salt was studied. The unit consists of two metal concentric cylindrical vessels, connected together to form a double-walled vessel. The volume between walls was filled with a certain amount of nitrate based phase change material (solar salt). In order to characterize the TSU, a test bench used to assess solar cooker performance was adopted. Experimental load tests with the TSU were carried out to evaluate the cooker performance. The obtained preliminary results show that the adoption of the solar salt TSU seems to allow both the opportunity of evening cooking and the possibility to better stabilize the cooker temperature when sky conditions are variable.

  13. Interference filters for colored glazed thermal solar collectors

    Energy Technology Data Exchange (ETDEWEB)

    Schueler, A.; Roecker, C.; Scartezzini, J.-L. [Swiss Federal Institute of Technology EPFL, Laboratoire d' Energie Solaire et de Physique du Batiment LESO-PB, Lausanne (Switzerland); Boudaden, J.; Videnovic, I. R.; Ho, R. S-C.; Oelhafen, P. [Institut fuer Physik der Universitaet Basel, Basel (Switzerland)

    2003-07-01

    Glazed thermal solar collectors, typically equipped with black, optical selective absorber sheets, exhibit good energy conversion efficiency. However, the black color, and sometimes the visibility of tubes and corrugations of the metal sheets, limit the architectural integration into buildings. In order to overcome this drawback, interference filters are considered as a promising approach. Multilayered thin film stacks deposited on the cover glass can produce a colored reflection hiding the black absorber without a great loss of energy. These interference filters are designed and optimized by numerical simulation. Such coatings can be deposited by vacuum processes (e.g. magnetron sputtering) or via the SolGel method. Optical measurements, such as spectrophotometry or ellipsometry, are used to determine film thicknesses and optical constants of individual layers, and to measure color coordinates and solar transmission for the multilayer stacks. (authors)

  14. Fifth parabolic dish solar thermal power program annual review: proceedings

    Energy Technology Data Exchange (ETDEWEB)

    None

    1984-03-01

    The primary objective of the Review was to present the results of activities within the Parabolic Dish Technology and Module/Systems Development element of the Department of Energy's Solar Thermal Energy Systems Program. The Review consisted of nine technical sessions covering overall Project and Program aspects, Stirling and Brayton module development, concentrator and engine/receiver development, and associated hardware and test results to date; distributed systems operating experience; international dish development activities; and non-DOE-sponsored domestic dish activities. A panel discussion concerning business views of solar electric generation was held. These Proceedings contain the texts of presentations made at the Review, as submitted by their authors at the beginning of the Review; therefore, they may vary slightly from the actual presentations in the technical sessions.

  15. Thermal energy storage for a space solar dynamic power system

    Science.gov (United States)

    Faget, N. M.; Fraser, W. M., Jr.; Simon, W. E.

    1985-01-01

    In the past, NASA has employed solar photovoltaic devices for long-duration missions. Thus, the Skylab system has operated with a silicon photovoltaic array and a nickel-cadmium electrochemical system energy storage system. Difficulties regarding the employment of such a system for the larger power requirements of the Space Station are related to a low orbit system efficiency and the large weight of the battery. For this reason the employment of a solar dynamic power system (SDPS) has been considered. The primary components of an SDPS include a concentrating mirror, a heat receiver, a thermal energy storage (TES) system, a thermodynamic heat engine, an alternator, and a heat rejection system. The heat-engine types under consideration are a Brayton cycle engine, an organic Rankine cycle engine, and a free-piston/linear-alternator Stirling cycle engine. Attention is given to a system description, TES integration concepts, and a TES technology assessment.

  16. Multi-Use Solar Thermal System for Oxygen Production from Lunar Regolith [7227-570] Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to develop an innovative solar thermal system for oxygen production from lunar regolith. In this system solar radiation is collected by the concentrator...

  17. Near-Field Thermal Radiation for Solar Thermophotovoltaics and High Temperature Thermal Logic and Memory Applications

    Science.gov (United States)

    Elzouka, Mahmoud

    This dissertation investigates Near-Field Thermal Radiation (NFTR) applied to MEMS-based concentrated solar thermophotovoltaics (STPV) energy conversion and thermal memory and logics. NFTR is the exchange of thermal radiation energy at nano/microscale; when separation between the hot and cold objects is less than dominant radiation wavelength (˜1 mum). NFTR is particularly of interest to the above applications due to its high rate of energy transfer, exceeding the blackbody limit by orders of magnitude, and its strong dependence on separation gap size, surface nano/microstructure and material properties. Concentrated STPV system converts solar radiation to electricity using heat as an intermediary through a thermally coupled absorber/emitter, which causes STPV to have one of the highest solar-to-electricity conversion efficiency limits (85.4%). Modeling of a near-field concentrated STPV microsystem is carried out to investigate the use of STPV based solid-state energy conversion as high power density MEMS power generator. Numerical results for In 0.18Ga0.82Sb PV cell illuminated with tungsten emitter showed significant enhancement in energy transfer, resulting in output power densities as high as 60 W/cm2; 30 times higher than the equivalent far-field power density. On thermal computing, this dissertation demonstrates near-field heat transfer enabled high temperature NanoThermoMechanical memory and logics. Unlike electronics, NanoThermoMechanical memory and logic devices use heat instead of electricity to record and process data; hence they can operate in harsh environments where electronics typically fail. NanoThermoMechanical devices achieve memory and thermal rectification functions through the coupling of near-field thermal radiation and thermal expansion in microstructures, resulting in nonlinear heat transfer between two temperature terminals. Numerical modeling of a conceptual NanoThermoMechanical is carried out; results include the dynamic response under

  18. Thermal instabilities in magnetically confined plasmas - Solar coronal loops

    Science.gov (United States)

    Habbal, S. R.; Rosner, R.

    1979-01-01

    The thermal stability of confined solar coronal structures ('loops') is investigated, following both normal mode and a new, global instability analysis. It is demonstrated that: (1) normal mode analysis shows modes with size scales comparable to that of loops to be unstable, but to be strongly affected by the loop boundary conditions; (2) a global analysis, based upon variation of the total loop energy losses and gains, yields loop stability conditions for global modes dependent upon the coronal loop heating process, with magnetically coupled heating processes giving marginal stability. The connection between the present analysis and the minimum flux corona of Hearn is also discussed.

  19. Promotion of solar thermal energy - guide and comparison of experience

    Energy Technology Data Exchange (ETDEWEB)

    Ballot, E. [ALTER Alsace (France)

    2004-01-01

    One of the objectives of the guide is to analyse the methods of the various partners of the project (Germany, Cyprus, Town of Barcelona and France) and to make a list with the most important ones, which could eventually be reproduced and adapted in other regions. Also, try to find out the problems that the various partners encounter (lack of information, technical and financial tools...), look for the best ways for developing the solar thermal energy and try to find out some answers from the stake holders of this domain and from our partners. (author)

  20. Solar-thermal-energy collection/storage-pond system

    Science.gov (United States)

    Blahnik, D.E.

    1982-03-25

    A solar thermal energy collection and storage system is disclosed. Water is contained, and the water surface is exposed directly to the sun. The central part of an impermeable membrane is positioned below the water's surface and above its bottom with a first side of the membrane pointing generally upward in its central portion. The perimeter part of the membrane is placed to create a watertight boundary separating the water into a first volume which is directly exposable to the sun and which touches the membranes first side, and a second volumn which touches the membranes second side. A salt is dissolved in the first water volume.

  1. Architectonic integration of solar thermal facilities; Integracion arquitectonica de instalaciones de energia solar termica

    Energy Technology Data Exchange (ETDEWEB)

    Lopez, G.; Martinez, J.

    2004-07-01

    This article proposes a procedure to achieve an appropriate architectural integration of a solar thermal system on a building taking into account urban planning, building typology, installation and construction factors that take part in the process of integration. Sun exposure of solar collectors is the main determinant since it affects directly to the design of the skin of the building. An appropriate analysis and resolution of the incorporation of the solar system in the 4 levels is arise in order to assure a correct integration of the system in the building. Starting from urban planning determining factors, a rational process of integration on the basis of the characteristics of the system, of the building and of its interrelation should guarantee an appropriate solution. (Author)

  2. Thermal Advantages for Solar Heating Systems with a Glass Cover with Antireflection Surfaces

    DEFF Research Database (Denmark)

    Furbo, Simon; Shah, Louise Jivan

    2003-01-01

    Investigations elucidate how a glass cover with antireflection surfaces can improve the efficiency of a solar collector and the thermal performance of solar heating systems. The transmittances for two glass covers for a flat-plate solar collector were measured for different incidence angles...... was determined for different solar heating systems. Three systems were investigated: solar domestic hot water systems, solar heating systems for combined space heating demand and domestic hot water supply, and large solar heating plants. The yearly thermal performance of the systems was calculated by detailed...... simulation models with collectors with a normal glass cover and with a glass cover with antireflection surfaces. The calculations were carried out for different solar fractions and temperature levels of the solar heating systems. These parameters influence greatly the thermal performance associated...

  3. Bionics in textiles: flexible and translucent thermal insulations for solar thermal applications.

    Science.gov (United States)

    Stegmaier, Thomas; Linke, Michael; Planck, Heinrich

    2009-05-13

    Solar thermal collectors used at present consist of rigid and heavy materials, which are the reasons for their immobility. Based on the solar function of polar bear fur and skin, new collector systems are in development, which are flexible and mobile. The developed transparent heat insulation material consists of a spacer textile based on translucent polymer fibres coated with transparent silicone rubber. For incident light of the visible spectrum the system is translucent, but impermeable for ultraviolet radiation. Owing to its structure it shows a reduced heat loss by convection. Heat loss by the emission of long-wave radiation can be prevented by a suitable low-emission coating. Suitable treatment of the silicone surface protects it against soiling. In combination with further insulation materials and flow systems, complete flexible solar collector systems are in development.

  4. Temperature comparison of different reflective surfaces of a solar thermal collector

    Science.gov (United States)

    Koh, Yit Yan; Chua, Yaw Long; Chin, Kiat Keong

    2017-09-01

    With the rapid depletion of fossil fuels, the search for application of alternative energy sources becomes more important than ever before. Solar energy has been identified as one of the major renewable energy that will contribute to power generation is years to come. There are two major categories of solar energy applications. Solar thermal collector is one of it. This paper presents an investigation on the effect of different reflecting surfaces on solar thermal collector. Three different reflective surfaces were applied on the surface of the solar thermal collector. Data was collected and analyzed. From the results, the aluminum mirror sheet performed best.

  5. European research school on large scale solar thermal – SHINE

    DEFF Research Database (Denmark)

    Bales, Chris; Forteza, Pau Joan Cortés; Furbo, Simon

    2014-01-01

    at companies. The PhD students all started during the early part of 2014 and their initial work has concentrated on literature studies and on setting up models and data collection to be used for validation purposes. The PhD students will complete their studies in 2017-18....

  6. Thermal performance of a single-basin solar still integrated with a shallow solar pond

    Energy Technology Data Exchange (ETDEWEB)

    El-Sebaii, A.A.; Ramadan, M.R.I.; Aboul-Enein, S.; Salem, N. [Department of Physics, Faculty of Science, Tanta University, Tanta (Egypt)

    2008-10-15

    In an attempt to improve the daily productivity of the single effect solar stills, a single-slope single-basin solar still integrated with a shallow solar pond (SSP) was studied to perform solar distillation at a relatively high temperature. The energy balance equations of various elements of the considered system were formulated and solved analytically. Suitable computer programs were prepared for optimizing and predicting the thermal performance of the considered system. Numerical calculations were carried out on typical summer and winter days in Tanta (latitude 30 47'N) for different thicknesses and mass flow rates of the flowing water to study the effect of these parameters on the daily productivity and efficiency of the system. To validate the proposed theoretical model, comparisons between calculated and measured results were carried out. Good agreement has been achieved. The year-round performances of the still with and without the SSP were also investigated. The optimum values of the flowing water thickness and the mass flow rate for this typical configuration of the SSP-active solar still were obtained as 0.03 m and 0.0009 kg/s. The annual average values of the daily productivity anti P{sub d} and efficiency anti {eta}{sub d} of the still with the SSP were found to be higher than those obtained without the SSP by 52.36% and 43.80%, respectively. (author)

  7. Identification and analysis of factors affecting thermal shock resistance of ceramic materials in solar receivers

    Science.gov (United States)

    Hasselman, D. P. H.; Singh, J. P.; Satyamurthy, K.

    1980-01-01

    An analysis was conducted of the possible modes of thermal stress failure of brittle ceramics for potential use in point-focussing solar receivers. The pertinent materials properties which control thermal stress resistance were identified for conditions of steady-state and transient heat flow, convective and radiative heat transfer, thermal buckling and thermal fatigue as well as catastrophic crack propagation. Selection rules for materials with optimum thermal stress resistance for a particular thermal environment were identified. Recommendations for materials for particular components were made. The general requirements for a thermal shock testing program quantitatively meaningful for point-focussing solar receivers were outlined. Recommendations for follow-on theoretical analyses were made.

  8. Investigating effect of different reflective surfaces on solar thermal collector

    Science.gov (United States)

    Chua, Yaw Long; Chin, Kiat Keong; Tay, Tee Tiong

    2017-11-01

    This paper reports on the experiments conducted to investigate the efficiency of different type of reflecting surfaces used on solar thermal collector. Three types of commonly available reflective surfaces coated with silver colour acrylic paint, reflective aluminium foil and blank compact disc are investigated. In this paper, the effect of different reflective surfaces on the water container and parabolic concentrator dish are investigated. In the first experiment, two types of surfaces, coated with silver colour acrylic paint and black colour acrylic paint on an aluminium container are compared. The other factors that might influence the experiment outcome like the material, focal point, and weather condition are kept constant. The experiment results proved that black colour surface is better in absorbing heat reflected by the parabolic dish. The second experiment focused on investigating the effect of different reflective surfaces on the parabolic concentrator dish itself. These surfaces are tested on a parabolic disc of a static solar thermal collector that reflects heat from the sun to a body of water stored in a black colour aluminium container. The temperature of the water is measured at a predetermined interval to measure the efficiency of the reflective surfaces used. It is found that the aluminium reflective surface performed the best compared to the other surfaces.

  9. Thermal buffering of receivers for parabolic dish solar thermal power plants

    Science.gov (United States)

    Manvi, R.; Fujita, T.; Gajanana, B. C.; Marcus, C. J.

    A parabolic dish solar thermal power plant comprises a field of parabolic dish power modules where each module is composed of a two-axis tracking parabolic dish concentrator which reflects sunlight (insolation) into the aperture of a cavity receiver at the focal point of the dish. The heat generated by the solar flux entering the receiver is removed by a heat transfer fluid. In the dish power module, this heat is used to drive a small heat engine/generator assembly which is directly connected to the cavity receiver at the focal point. A computer analysis is performed to assess the thermal buffering characteristics of receivers containing sensible and latent heat thermal energy storage. Parametric variations of the thermal inertia of the integrated receiver-buffer storage systems coupled with different fluid flow rate control strategies are carried out to delineate the effect of buffer storage, the transient response of the receiver-storage systems and corresponding fluid outlet temperature. It is concluded that addition of phase change buffer storage will substantially improve system operational characteristics during periods of rapidly fluctuating insolation due to cloud passage.

  10. Survey of solar thermal energy storage subsystems for thermal/electric applications

    Energy Technology Data Exchange (ETDEWEB)

    Segaser, C. L.

    1978-08-01

    A survey of the current technology and estimated costs of subsystems for storing the thermal energy produced by solar collectors is presented. The systems considered were capable of producing both electricity and space conditioning for three types of loads: a single-family detached residence, an apartment complex of 100 units, and a city of 30,000 residents, containing both single-family residences and apartments. Collector temperatures will be in four ranges: (1) 100 to 250/sup 0/F (used for space heating and single-cycle air conditioners and organic Rankine low-temperature turbines); (2) 300 to 400/sup 0/F (used for dual-cycle air conditioners and low-temperature turbines); (3) 400 to 600/sup 0/F (using fluids from parabolic trough collectors to run Rankine turbines); (4) 800 to 1000/sup 0/F (using fluids from heliostats to run closed-cycle gas turbines and steam Rankine turbines). The solar thermal energy subsystems will require from 60 to 36 x 10/sup 5/ kWhr (2.05 x 10/sup 5/ to 1.23 x 10/sup 10/ Btu) of thermal storage capacity. In addition to sensible heat and latent heat storage materials, several other media were investigated as potential thermal energy storage materials, including the clathrate and semiclathrate hydrates, various metal hydrides, and heat storage based on inorganic chemical reactions.

  11. Thermal performance of Danish solar combi systems in practice and in theory

    DEFF Research Database (Denmark)

    Andersen, Elsa; Shah, Louise Jivan; Furbo, Simon

    2004-01-01

    An overview of measured thermal performances of Danish solar combi systems in practice is given. The thermal performance varies greatly from system to system. Measured and calculated thermal performances of different solar combi systems are compared and the main reasons for the different thermal...... performances are given. Further, a parametric study on two solar combi system types is performed. Based on the investigation it can be concluded that the thermal performance first of all is influenced by the space heating consumption during the summer period and that the systems in practice perform...

  12. Nonimaging concentrators for solar thermal energy. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Winston, R.

    1980-03-21

    A small experimental solar collector test facility has been established on the campus of the University of Chicago. This capability has been used to explore applications of nonimaging optics for solar thermal concentration in three substantially different configurations: (1) a single stage system with moderate concentration on an evacuated absorber (a 5.25X evacuated tube Compound Parabolic Concentrator or CPC), (2) a two stage system with high concentration and a non-evacuated absorber (a 16X Fresnel lens/CPC type mirror) and (3) moderate concentration single stage systems with non-evacuated absorbers for lower temperature (a 3X and a 6.5X CPC). Prototypes of each of these systems have been designed, built and tested. The performance characteristics are presented. In addition a 73 m/sup 2/ experimental array of 3X non-evacuated CPC's has been installed in a school heating system on the Navajo Indian Reservation in New Mexico. The full array has a peak noon time efficiency of approx. 50% at ..delta..T = 50/sup 0/C above ambient and has supplied about half the school's heat load for the past two heating seasons. Several theoretical features of nonimaging concentration have been investigated including their long term energy collecting behavior. The measured performance of the different systems shows clearly that non-tracking concentrators can provide solar thermal energy from moderately high low temperature regimes (> 50/sup 0/C above ambient) up into the mid-temperature region (well above 200/sup 0/C above ambient). The measured efficiency at 220/sup 0/C for the 5.25X CPC was as high or higher than that for any of the commercial tracking systems tested.

  13. Thermal stress cycling of GaAs solar cells

    Science.gov (United States)

    Janousek, B. K.; Francis, R. W.; Wendt, J. P.

    1985-01-01

    A thermal cycling experiment was performed on GaAs solar cells to establish the electrical and structural integrity of these cells under the temperature conditions of a simulated low-Earth orbit of 3-year duration. Thirty single junction GaAs cells were obtained and tests were performed to establish the beginning-of-life characteristics of these cells. The tests consisted of cell I-V power output curves, from which were obtained short-circuit current, open circuit voltage, fill factor, and cell efficiency, and optical micrographs, spectral response, and ion microprobe mass analysis (IMMA) depth profiles on both the front surfaces and the front metallic contacts of the cells. Following 5,000 thermal cycles, the performance of the cells was reexamined in addition to any factors which might contribute to performance degradation. It is established that, after 5,000 thermal cycles, the cells retain their power output with no loss of structural integrity or change in physical appearance.

  14. Formation of the thermal infrared continuum in solar flares

    Science.gov (United States)

    Simões, Paulo J. A.; Kerr, Graham S.; Fletcher, Lyndsay; Hudson, Hugh S.; Giménez de Castro, C. Guillermo; Penn, Matt

    2017-09-01

    Aims: Observations of the Sun with the Atacama Large Millimeter Array have now started, and the thermal infrared will regularly be accessible from the NSF's Daniel K. Inouye Solar Telescope. Motivated by the prospect of these new data, and by recent flare observations in the mid infrared, we set out here to model and understand the source of the infrared continuum in flares, and to explore its diagnostic capability for the physical conditions in the flare atmosphere. Methods: We use the one-dimensional (1D) radiation hydrodynamics code RADYN to calculate mid-infrared continuum emission from model atmospheres undergoing sudden deposition of energy by non-thermal electrons. Results: We identify and characterise the main continuum thermal emission processes relevant to flare intensity enhancement in the mid- to far-infrared (2-200 μm) spectral range as free-free emission on neutrals and ions. We find that the infrared intensity evolution tracks the energy input to within a second, albeit with a lingering intensity enhancement, and provides a very direct indication of the evolution of the atmospheric ionisation. The prediction of highly impulsive emission means that, on these timescales, the atmospheric hydrodynamics need not be considered in analysing the mid-IR signatures.

  15. Interfacial thermal degradation in inverted organic solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Greenbank, William; Hirsch, Lionel; Wantz, Guillaume; Chambon, Sylvain, E-mail: sylvain.chambon@ims-bordeaux.fr [University of Bordeaux, CNRS, Bordeaux INP, IMS, UMR 5218, F-33405 Talence (France)

    2015-12-28

    The efficiency of organic photovoltaic (OPV) solar cells is constantly improving; however, the lifetime of the devices still requires significant improvement if the potential of OPV is to be realised. In this study, several series of inverted OPV were fabricated and thermally aged in the dark in an inert atmosphere. It was demonstrated that all of the devices undergo short circuit current-driven degradation, which is assigned to morphology changes in the active layer. In addition, a previously unreported, open circuit voltage-driven degradation mechanism was observed that is highly material specific and interfacial in origin. This mechanism was specifically observed in devices containing MoO{sub 3} and silver as hole transporting layers and electrode materials, respectively. Devices with this combination were among the worst performing devices with respect to thermal ageing. The physical origins of this mechanism were explored by Rutherford backscattering spectrometry and atomic force microscopy and an increase in roughness with thermal ageing was observed that may be partially responsible for the ageing mechanism.

  16. A New European High Fidelity Solar Array Simulator for Near Earth and Deep Space Applications

    Directory of Open Access Journals (Sweden)

    Thorvardarson Hjalti Pall

    2017-01-01

    Full Text Available Following an intensive design, development, and testing effort of almost 3 years, Rovsing with ESA assistance succeeded in the development of a new European high fidelity Solar Array Simulator (SAS for near Earth and deep space applications. ESA now has a versatile, highly modular and efficient SAS at its disposition that serves at simulating modern high power solar arrays for Earth observation, science or telecom satellites as well as for future deep space missions.

  17. Biaxial-Type Concentrated Solar Tracking System with a Fresnel Lens for Solar-Thermal Applications

    Directory of Open Access Journals (Sweden)

    Tsung Chieh Cheng

    2016-04-01

    Full Text Available In this paper, an electromechanical, biaxial-type concentrated solar tracking system was designed for solar-thermal applications. In our tracking system, the sunlight was concentrated by the microstructure of Fresnel lens to the heating head of the Stirling engine and two solar cells were installed to provide the power for tracking system operation. In order to obtain the maximum sun power, the tracking system traces the sun with the altitude-azimuth biaxial tracing method and accurately maintains the sun’s radiation perpendicular to the plane of the heating head. The results indicated that the position of heating head is an important factor for power collection. If the sunlight can be concentrated to completely cover the heating head with small heat loss, we can obtain the maximum temperature of the heating head of the Stirling engine. Therefore, the temperature of heating head can be higher than 1000 °C in our experiment on a sunny day. Moreover, the results also revealed that the temperature decrease of the heating head is less than the power decrease of solar irradiation because of the latent heat of copper and the small heat loss from the heating head.

  18. High temperature thermal storage for solar gas turbines using encapsulated phase change materials

    CSIR Research Space (South Africa)

    Klein, P

    2014-01-01

    Full Text Available The development of high temperature thermal storage systems is required to increase the solar share of solar-hybrid gas turbine cycles. This paper proposes a pressurised packed bed of Encapsulated Phase Change Materials (EPCM) as a thermal storage...

  19. Finding India’s place in the Sun –Prospects for harnessing solar thermal energy

    OpenAIRE

    Sundaram, Vijay; Natarajan, Vasant

    2010-01-01

    In this article, we describe our ongoing efforts in addressing the environment and energy challenges facing the world today. Tapping solar thermal energy seems to be the right choice for a country like India. We look at three solar-thermal technologies in the laboratory — water purification/distillation, Stirling engine, and air-conditioning/refrigeration.

  20. Thermal Modeling of the Mars Reconnaissance Orbiter's Solar Panel and Instruments during Aerobraking

    Science.gov (United States)

    Dec, John A.; Gasbarre, Joseph F.; Amundsen, Ruth M.

    2007-01-01

    The Mars Reconnaissance Orbiter (MRO) launched on August 12, 2005 and started aerobraking at Mars in March 2006. During the spacecraft s design phase, thermal models of the solar panels and instruments were developed to determine which components would be the most limiting thermally during aerobraking. Having determined the most limiting components, thermal limits in terms of heat rate were established. Advanced thermal modeling techniques were developed utilizing Thermal Desktop and Patran Thermal. Heat transfer coefficients were calculated using a Direct Simulation Monte Carlo technique. Analysis established that the solar panels were the most limiting components during the aerobraking phase of the mission.

  1. On the response of the European climate to solar/geomagnetic long-term activity

    Directory of Open Access Journals (Sweden)

    Georgeta Maris

    2010-12-01

    Full Text Available The response of the European climate to long-term solar/geomagnetic activity is investigated using surface-air temperature and solar/geomagnetic indices. A set of 21 time series of air temperatures measured at European stations between 1900 and 2006, and 4 European and 14 Romanian stations with 150-year-long records, were used. Strong and coherent solar signals were found at Schwabe and Hale solar-cycle timescales, with peak-to-trough amplitudes of several degrees, and 0.6 ˚C to 0.8 ˚C, respectively. Interdecadal and centennial trends as defined by 11-year and 22-year running averages, respectively, of the annual mean time series differ significantly from corresponding trends in solar/geomagnetic activity, which indicates the presence of temperature variations at a 40-year timescale that are possibly related to the internal dynamics of the atmospheric system. The data show similar temporal behaviors at all of the stations analyzed, with amplitude differences that can be understood in terms of large-scale atmospheric circulation patterns that are influenced by the solar/geomagnetic forcing at the corresponding timescales, although with local intensity differences.

  2. Mathematical Modeling and Numerical Analysis of Thermal Distribution in Arch Dams considering Solar Radiation Effect

    Science.gov (United States)

    Mirzabozorg, H.; Hariri-Ardebili, M. A.; Shirkhan, M.; Seyed-Kolbadi, S. M.

    2014-01-01

    The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams. PMID:24695817

  3. Improvement of energy performances of existing buildings by application of solar thermal systems

    Directory of Open Access Journals (Sweden)

    Krstić-Furundžić Aleksandra

    2009-01-01

    Full Text Available Improvement of energy performances of the existing buildings in the suburban settlement Konjarnik in Belgrade, by the application of solar thermal systems is the topic presented in this paper. Hypothetical models of building improvements are created to allow the benefits of applying solar thermal collectors to residential buildings in Belgrade climate conditions to be estimated. This case study presents different design variants of solar thermal collectors integrated into a multifamily building envelope. The following aspects of solar thermal systems integration are analyzed in the paper: energy, architectural, ecological and economic. The results show that in Belgrade climatic conditions significant energy savings and reduction of CO2 emissions can be obtained with the application of solar thermal collectors.

  4. Standard Practice for Evaluating Solar Absorptive Materials for Thermal Applications

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This practice covers a testing methodology for evaluating absorptive materials used in flat plate or concentrating collectors, with concentrating ratios not to exceed five, for solar thermal applications. This practice is not intended to be used for the evaluation of absorptive surfaces that are (1) used in direct contact with, or suspended in, a heat-transfer liquid, (that is, trickle collectors, direct absorption fluids, etc.); (2) used in evacuated collectors; or (3) used in collectors without cover plate(s). 1.2 Test methods included in this practice are property measurement tests and aging tests. Property measurement tests provide for the determination of various properties of absorptive materials, for example, absorptance, emittance, and appearance. Aging tests provide for exposure of absorptive materials to environments that may induce changes in the properties of test specimens. Measuring properties before and after an aging test provides a means of determining the effect of the exposure. 1.3 Th...

  5. Solar thermal upper stage: Economic advantage and development status

    Science.gov (United States)

    Adams, Alan M.

    1995-01-01

    A solar thermal upper stage (STUS) is envisioned as a propulsive concept for the future. The STUS will be used for low Earth orbit (LEO) to geostationary-Earth orbit (GEO) transfer and for planetary exploration missions. The STUS offers significant performance gains over conventional chemical propulsion systems. These performance gains translate into a more economical, more efficient method of placing useful payloads in space and maximizing the benefits derived from space activity. This paper will discuss the economical advantages of an STUS compared to conventional chemical propulsion systems, the potential market for an STUS, and the recent activity in the development of an STUS. The results of this assessment combined with the performance gains, will provide a strong justification for the development of an STUS.

  6. Second national symposium `Thermal solar energy`; Zweites nationales Symposium Thermische Solarenergie

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    The symposium on thermal solar energy utilization focussed on embracing aspects of thermal solar energy, standardization, testing, quality assurance, and the use of passive solar energy. Each of the 23 papers given at the meeting was abstracted for separate entry into the data base. (BWI). [Deutsch] Im Mittelpunkt des Symposiums zur thermischen Solarenergienutzung stehen uebergreifende Aspekte der thermischen Solarenergie, Normung, Test und Qualitaetssicherung sowie die Nutzung der passiven Solarenergie. Fuer alle 23 enthaltenen Fachbeitraege wurde eine gesonderte inhaltliche Erschliessung durchgefuehrt. (BWI).

  7. STDAC: Solar Thermal Design Assistance Center annual report fiscal year 1994

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-12-31

    The Solar Thermal Design Assistance Center (STDAC) at Sandia is a resource provided by the DOE Solar Thermal Program. The STDAC`s major objective is to accelerate the use of solar thermal systems by providing direct technical assistance to users in industry, government, and foreign countries; cooperating with industry to test, evaluate, and develop renewable energy systems and components; and educating public and private professionals, administrators, and decision makers. This FY94 report highlights the activities and accomplishments of the STDAC. In 1994, the STDAC continued to provide significant direct technical assistance to domestic and international organizations in industry, government, and education, Applying solar thermal technology to solve energy problems is a vital element of direct technical assistance. The STDAC provides information on the status of new, existing, and developing solar technologies; helps users screen applications; predicts the performance of components and systems; and incorporates the experience of Sandia`s solar energy personnel and facilities to provide expert guidance. The STDAC directly enhances the US solar industry`s ability to successfully bring improved systems to the marketplace. By collaborating with Sandia`s Photovoltaic Design Assistance Center and the National Renewable Energy Laboratory the STDAC is able to offer each customer complete service in applying solar thermal technology. At the National Solar Thermal Test Facility the STDAC tests and evaluates new and innovative solar thermal technologies. Evaluations are conducted in dose cooperation with manufacturers, and the results are used to improve the product and/or quantify its performance characteristics. Manufacturers, in turn, benefit from the improved design, economic performance, and operation of their solar thermal technology. The STDAC provides cost sharing and in-kind service to manufacturers in the development and improvement of solar technology.

  8. Low Molecular Weight Norbornadiene Derivatives for Molecular Solar?Thermal Energy Storage

    OpenAIRE

    Quant, Maria; Lennartson, Anders; Dreos, Ambra; Kuisma, Mikael; Erhart, Paul; B?rjesson, Karl; Moth?Poulsen, Kasper

    2016-01-01

    Abstract Molecular solar?thermal energy storage systems are based on molecular switches that reversibly convert solar energy into chemical energy. Herein, we report the synthesis, characterization, and computational evaluation of a series of low molecular weight (193?260?g?mol?1) norbornadiene?quadricyclane systems. The molecules feature cyano acceptor and ethynyl?substituted aromatic donor groups, leading to a good match with solar irradiation, quantitative photo?thermal conversion between t...

  9. Solar import from Africa : The Italian and the European perspective

    NARCIS (Netherlands)

    Migliavacca, G.; L'Abbate, A.; Calisti, R.; Soranno, M.; Brancucci Martinez-anido, C.; Alecu, C.; Vandenbergh, M.; Fulli, G.

    2012-01-01

    Goal of the present work is to provide a first preliminary analysis on the effect of African solar energy import on the Italian system at 2030. In particular, the aim is to provide a first preliminary answer to questions like: · what flow will prevail in Italy at 2030 (wind from the Northern border

  10. Heat engine requirements for advanced solar thermal power systems

    Science.gov (United States)

    Jaffe, L. D.; Pham, H. Q.

    1981-01-01

    Requirements and constraints are established for power conversion subsystems, including heat engine, alternator and auxiliaries, of dish concentrator solar thermal power systems. In order to be competitive with conventional power systems, it is argued that the heat engine should be of less than 40 kW rated output, in a subsystem with an efficiency of at least 40% at rated output and at least 37% at half power. An interval between major overhauls of 50,000 hours is also desirable, along with minor maintenance and lubrication not more than four times a year requiring no more than one man-hour each time, and optimal reliability. Also found to be important are the capability for hybrid operation using heat from a solar receiver, fuel-fired combustor or both simultaneously, operation at any attitude, stability to transients in input power and output loading, operation at ambient temperatures from -30 to 50 C, and compatibility with environmental and safety requirements. Cost targets include a price of $180/kWe, and operation, maintenance and replacement costs averaging $0.001/kWh for 30 years of operation.

  11. A solar thermal electric power plant for small communities

    Science.gov (United States)

    Holl, R. J.

    1979-01-01

    A solar power plant has been designed with a rating of 1000-kW electric and a 0.4 annual capacity factor. It was configured as a prototype for plants in the 1000 to 10,000-kWe size range for application to small communities or industrial users either grid-connected or isolated from a utility grid. A small central receiver was selected for solar energy collection after being compared with alternative distributed collectors. Further trade studies resulted in the selection of Hitec (heat transfer salt composed of 53 percent KNO3, 40 percent NaNO2, 7 percent NaNO3) as both the receiver coolant and the sensible heat thermal stroage medium and the steam Rankine cycle for power conversion. The plant is configured with road-transportable units to accommodate remote sites and minimize site assembly requirements. Results of the analyses indicate that busbar energy costs are competitive with diesel-electric plants in certain situations, e.g., off-grid, remote regions with high insolation. Sensitivity of energy costs to plant power rating and system capacity factor are given.

  12. Recent experience with large solar thermal systems in The Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Bokhoven, T.P.; Dam, J. Van; Kratz, P. [ZEN-International bv, Gouda (Netherlands)

    2001-07-01

    Since 1995, two large solar thermal systems (1200 and 2400 m{sup 2}) have been realised in The Netherlands for industrial purposes. It is expected that large solar systems will be used more often in the coming years. For that reason and for the benefit of successful solar projects, important practical experience with these large systems is reported. In 1995/1996, a system was constructed in Lisse for the purpose of agricultural drying and conditioning, consisting of a 1200-m{sup 2} (high performance) flat-plate collector array and a 1000-m{sup 3} water storage tank. The tank has been constructed as the foundation of a warehouse building and is situated below groundwater level. The combination of these two conditions, together with the other storage parameters, has given grounds for many extra design considerations compared to other underground storage units. Special details had to be designed, for these specific conditions, concerning leakages (in/out of the tank), anti-floating measures and underwater insulation which is stable at high temperatures. The lessons learned in this project can be of value for those considering the construction of this kind of underground storage unit. In 1996/1997, a 2400-m{sup 2} system was realised in Breda at a confectionery factory (van Melle), in which the drain-back concept was used on such a scale for the first time. The various design characteristics for drain-back systems, as were already known from two decades of usage in small domestic hot water systems, were upscaled to a 'super drain-back' system. The scale of the project further emphasised the advantages of this concept in cost (both operational and investment), performance and safety. However, the size of the system also brought some unexpected side effects which should be taken into account in future designs. (Author)

  13. Decadal variability of European sea level extremes in relation to the solar activity

    Science.gov (United States)

    Martínez-Asensio, Adrián.; Tsimplis, Michael N.; Calafat, Francisco Mir

    2016-11-01

    This study investigates the relationship between decadal changes in solar activity and sea level extremes along the European coasts and derived from tide gauge data. Autumn sea level extremes vary with the 11 year solar cycle at Venice as suggested by previous studies, but a similar link is also found at Trieste. In addition, a solar signal in winter sea level extremes is also found at Venice, Trieste, Marseille, Ceuta, Brest, and Newlyn. The influence of the solar cycle is also evident in the sea level extremes derived from a barotropic model with spatial patterns that are consistent with the correlations obtained at the tide gauges. This agreement indicates that the link to the solar cycle is through modulation of the atmospheric forcing. The only atmospheric regional pattern that showed variability at the 11 year period was the East Atlantic pattern.

  14. Efficient Solar-Thermal Energy Harvest Driven by Interfacial Plasmonic Heating-Assisted Evaporation.

    Science.gov (United States)

    Chang, Chao; Yang, Chao; Liu, Yanming; Tao, Peng; Song, Chengyi; Shang, Wen; Wu, Jianbo; Deng, Tao

    2016-09-07

    The plasmonic heating effect of noble nanoparticles has recently received tremendous attention for various important applications. Herein, we report the utilization of interfacial plasmonic heating-assisted evaporation for efficient and facile solar-thermal energy harvest. An airlaid paper-supported gold nanoparticle thin film was placed at the thermal energy conversion region within a sealed chamber to convert solar energy into thermal energy. The generated thermal energy instantly vaporizes the water underneath into hot vapors that quickly diffuse to the thermal energy release region of the chamber to condense into liquids and release the collected thermal energy. The condensed water automatically flows back to the thermal energy conversion region under the capillary force from the hydrophilic copper mesh. Such an approach simultaneously realizes efficient solar-to-thermal energy conversion and rapid transportation of converted thermal energy to target application terminals. Compared to conventional external photothermal conversion design, the solar-thermal harvesting device driven by the internal plasmonic heating effect has reduced the overall thermal resistance by more than 50% and has demonstrated more than 25% improvement of solar water heating efficiency.

  15. Evaluation of solar thermal storages with quantitative flow visualisation

    Energy Technology Data Exchange (ETDEWEB)

    Logie, W.; Frank, E.; Luzzi, A.

    2008-07-15

    The non-intrusive Quantitative Flow Visualisation (QFV) Techniques of Particle Imaging Velocimetry (PIV) and Laser Induced Fluorescence (LIF) have been evaluated in the context of experimental investigations on solar Thermal Energy Storages (TES). Much competence and experience has been gained in the integration of these powerful yet complex and time consuming flow analysis methods into the realm of laboratory experimentation. In addition to gathering experience in the application of QFV techniques, a number of charging and discharging variations were considered in light of exergetic evaluation for the influence they have on the ability of a TES to stratify. The contemporary awareness that poorly chosen pitch to diameter ratios by the design of immersed coil heat exchangers leads to a reduction in heat exchange and an increase in mixing phenomenon has been confirmed. The observation of two combitank (combined domestic hot water and space heating) configurations has shown that free convective heat transfer forces in the form of mixing energy play a significant role in the stratification efficiency of thermal energy storages. (author)

  16. Theoretical variations of the thermal performance of different solar collectors and solar combi systems as function of the varying yearly weather conditions in Denmark

    DEFF Research Database (Denmark)

    Andersen, Elsa; Furbo, Simon

    2009-01-01

    The thermal performances of solar collectors and solar combi systems with different solar fractions are studied under the influence of the Danish Design Reference Year, DRY data file, and measured weather data from a solar radiation measurement station situated at the Technical University...... collector or the annual global radiation. Solar combi systems with high efficient solar collectors are more influenced by weather variations from one year to another than systems with low efficient solar collectors. The annual thermal performance of solar collectors cannot be predicted from the global...

  17. Comparison of Thermal Performances of Fixed and Tracking Solar Collectors With Computational Fluid Dynamics

    OpenAIRE

    Keçel, Selçuk

    2015-01-01

    Solar collectors, one of the important areas of use for solar power, are based on the principle of heating water flowing through piping systems with solar radiation. Collectors are mostly fixed with various constructions on roofs of buildings, which provide hot water. Efficiency differences between fixed systems and tracking systems are generally compared over efficiencies of photovoltaic systems. As a different this study, the thermal analysis of solar collector systems to be installed on tw...

  18. Solar thermal energy utilization in Brazil: a perspective; Utilizacao da energia solar termica no Brasil: uma perspectiva

    Energy Technology Data Exchange (ETDEWEB)

    Miller, Francisco Mateus [PETROBRAS, Rio de Janeiro, RJ (Brazil)

    2004-07-01

    Although Brazil has a large insolation potential, utilization of solar thermal energy is still limited to few applications, like residential and commercial water heating and drying of grains. However, there are in other countries more intensive applications, like electricity generation, industrial heat and fresh water production. The present work describes which are the other ways of using solar thermal energy that have been developed in the world, approaches the main technical aspects that affect its utilization, the perspective of increasing it in Brazil and its possible barriers and, finally, PETROBRAS' studies in this area, positioning itself as an Energy Company. The main solar thermal technologies currently used in the world are evacuated collectors, that work efficiently at temperatures up to 130 deg C, and concentrating solar technologies, that can reach the temperature of 1200 deg C. Among the latter, solar trough is the technology that is already considered mature, and near to become economically viable. Brazil, at the moment, has two technological challenges: development of national technology to manufacture high performance solar collectors, like evacuated collectors and solar troughs, and the development of thermal equipment to operate at temperatures under 120 deg C, like adsorption and absorption chillers and desalination towers, that can be economically competitive. (author)

  19. Ancillary Services for the European Grid with High Shares of Wind and Solar Power

    DEFF Research Database (Denmark)

    Van Hulle, Frans; Holttinen, Hannele; Kiviluoma, Juha

    2012-01-01

    With significantly increasing share of variable renewable power generation like wind and solar PV, the need in the power system for ancillary services supporting the network frequency, voltage, etc. changes. Turning this issue around, market opportunities will emerge for wind and solar PV...... technology to deliver such grid services. In the European power system, adequate market mechanisms need to be developed to ensure that there will be an efficient trading of these services. For that purpose a range of (economic) characteristics of wind (and solar) power as providers of grid services need...... to be better understood. This relates both to the technical capabilities of the plants for delivering specific services and to the quantification of the needs. The paper presents the approach of the European IEE project REserviceS, aiming at establishing reference guidance for the ongoing developments...

  20. An overview of water disinfection in developing countries and the potential for solar thermal water pasteurization

    Energy Technology Data Exchange (ETDEWEB)

    Burch, J.; Thomas, K.E.

    1998-01-01

    This study originated within the Solar Buildings Program at the U.S. Department of Energy. Its goal is to assess the potential for solar thermal water disinfection in developing countries. In order to assess solar thermal potential, the alternatives must be clearly understood and compared. The objectives of the study are to: (a) characterize the developing world disinfection needs and market; (b) identify competing technologies, both traditional and emerging; (c) analyze and characterize solar thermal pasteurization; (d) compare technologies on cost-effectiveness and appropriateness; and (e) identify research opportunities. Natural consequences of the study beyond these objectives include a broad knowledge of water disinfection problems and technologies, introduction of solar thermal pasteurization technologies to a broad audience, and general identification of disinfection opportunities for renewable technologies.

  1. Benefits of full scope simulators during solar thermal power plants design and construction

    Science.gov (United States)

    Gallego, José F.; Gil, Elena; Rey, Pablo

    2017-06-01

    In order to efficiently develop high-precision dynamic simulators for solar thermal power plants, Tecnatom adapted its simulation technology to consider solar thermal models. This effort and the excellent response of the simulation market have allowed Tecnatom to develop simulators with both parabolic trough and solar power tower technologies, including molten salt energy storage. These simulators may pursue different objectives, giving rise to training or engineering simulators. Solar thermal power market combines the need for the training of the operators with the potential benefits associated to the improvement of the design of the plants. This fact along with the simulation capabilities enabled by the current technology and the broad experience of Tecnatom present the development of an engineering+training simulator as a very advantageous option. This paper describes the challenge of the development and integration of a full scope simulator during the design and construction stages of a solar thermal power plant, showing the added value to the different engineering areas.

  2. Experimental Investigation of Latent Heat Thermal Energy Storage for Bi-Modal Solar Thermal Propulsion (Briefing Charts)

    Science.gov (United States)

    2014-07-01

    performance of 28,100 kg, shuttle launched spacecraft for LEO-GEO transfer Engine Type LO2-H2 Ion Solar 1 Solar 2 ΔV (m/s) 4,270 5,850 5,850 4,800...Comparison Metrics Solar Thermal w/o Energy Storage Chemical Thrusters Electric Propulsion • Eliminated PCM and TPV • Reduced solar collector ...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) July 2014 2. REPORT TYPE Briefing

  3. Solar thermal power plants in small utilities - An economic impact analysis

    Science.gov (United States)

    Bluhm, S. A.; Ferber, R. R.; Mayo, L. G.

    1979-01-01

    A study was performed to assess the potential economic impact of small solar thermal electric power systems in statistically representative synthetic small utilities of the Southwestern United States. Power supply expansion plans were compared on the basis of present worth of future revenue requirements for 1980-2000 with and without solar thermal plants. Coal-fired and oil-fired municipal utility expansion plans with 5 percent solar penetration were 0.5 percent and 2.25 percent less expensive, respectively, than the corresponding conventional plan. At $969/kWe, which assumes the same low cost solar equipment but no improvement in site development costs, solar penetration of 5 percent in the oil-fired municipal reduced revenue requirements 0.88 percent. The paper concludes that some solar thermal plants are potentially economic in small community utilities of the Southwest.

  4. Solar wall heating and daylight use with transparent thermal insulation - the solar environmental wall; Solare Wandheizung und Tageslichtnutzung mit Transparenter Waermedaemmung - die Solare Umweltwand

    Energy Technology Data Exchange (ETDEWEB)

    Platzer, W. [Fachverband Transparente Waermedaemmung e.V., Gundelfingen (Germany)

    2005-07-01

    Construction with the sun means to open building walls for the sun. The building is supposed to benefit directly from daylight and solar heat. Special materials were developed for this purpose, which combine solar transmission and light transmission. They enable the transparent thermal insulation of buildings, abbreviated TWD. Their integration into the facade and the roof offer an intelligent and uncomplicated technology for the use of solar energy, the ''solar environmental wall''. TWD-materials can be used as filling material in various building components and they already constitute a weather-resistant wall. They are thermally-insulating structures or materials, which keep out the heat but allow the transmission of solar radiation and light. TWD-materials maintain their excellent insulating properties almost unchanged even in case of very cold outer temperatures or inclined construction in the roof area. In these cases the convection of components that are only filled with air or gas, can lead to considerable decreases of the U-value (according to DIN EN 673 up to 45%). Good TWD-materials are resistant against humidity, which enables to use them in non-hermetic systems, such as e.g. U-profile glas, too. (orig.)

  5. Prediction of global solar irradiance based on time series analysis: Application to solar thermal power plants energy production planning

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Luis; Marchante, Ruth; Cony, Marco [Investigaciones y Recursos Solares Avanzados (IrSOLaV), Tres Cantos 2 8045 (Spain); Zarzalejo, Luis F.; Polo, Jesus; Navarro, Ana [Energy Department, CIEMAT, Madrid 28040 (Spain)

    2010-10-15

    Due to strong increase of solar power generation, the predictions of incoming solar energy are acquiring more importance. Photovoltaic and solar thermal are the main sources of electricity generation from solar energy. In the case of solar thermal energy plants with storage energy system, its management and operation need reliable predictions of solar irradiance with the same temporal resolution as the temporal capacity of the back-up system. These plants can work like a conventional power plant and compete in the energy stock market avoiding intermittence in electricity production. This work presents a comparisons of statistical models based on time series applied to predict half daily values of global solar irradiance with a temporal horizon of 3 days. Half daily values consist of accumulated hourly global solar irradiance from solar raise to solar noon and from noon until dawn for each day. The dataset of ground solar radiation used belongs to stations of Spanish National Weather Service (AEMet). The models tested are autoregressive, neural networks and fuzzy logic models. Due to the fact that half daily solar irradiance time series is non-stationary, it has been necessary to transform it to two new stationary variables (clearness index and lost component) which are used as input of the predictive models. Improvement in terms of RMSD of the models essayed is compared against the model based on persistence. The validation process shows that all models essayed improve persistence. The best approach to forecast half daily values of solar irradiance is neural network models with lost component as input, except Lerida station where models based on clearness index have less uncertainty because this magnitude has a linear behaviour and it is easier to simulate by models. (author)

  6. European Space Agency studies of the solar probe

    Science.gov (United States)

    Roxburgh, I. W.

    1978-01-01

    The feasibility and scientific objectives of a solar probe were studied by a Mission Definition Group in 1975 and 1976. The orbit analysis program was developed and an extended study of the orbit analysis was done in 1977. The results of these studies are in the Report of the Mission Definition Study (1976) and an E.S.O.C. report (1978), and the reader is referred to these sources for greater details. In this report, only brief discussion on mission concept and objectives, satellite design, orbit, orbit analysis, are presented.

  7. Evaluation of thermal control coatings for use on solar dynamic radiators in low earth orbit

    Science.gov (United States)

    Dever, Joyce A.; Rodriguez, Elvin; Slemp, Wayne S.; Stoyack, Joseph E.

    1991-01-01

    Thermal control coatings with high thermal emittance and low solar absorptance are needed for Space Station Freedom (SSF) solar dynamic power module radiator (SDR) surfaces for efficient heat rejection. Additionally, these coatings must be durable to low earth orbital (LEO) environmental effects of atomic oxygen, ultraviolet radiation and deep thermal cycles which occur as a result of start-up and shut-down of the solar dynamic power system. Eleven candidate coatings were characterized for their solar absorptance and emittance before and after exposure to ultraviolet (UV) radiation (200 to 400 nm), vacuum UV (VUV) radiation (100 to 200 nm) and atomic oxygen. Results indicated that the most durable and best performing coatings were white paint thermal control coatings Z-93, zinc oxide pigment in potassium silicate binder, and YB-71, zinc orthotitanate pigment in potassium silicate binder. Optical micrographs of these materials exposed to the individual environmental effects of atomic oxygen and vacuum thermal cycling showed that no surface cracking occurred.

  8. Influence of the spectral distribution of a solar simulator and of the outer diffuse radiation in the estimation of the optical yield of a thermal solar receiver; Influencia de la distribucion espectral de un simulador solar y de la radiacion difusa exterior en la estimacion del rendimiento optico de un captador solar termico

    Energy Technology Data Exchange (ETDEWEB)

    Sallaberry, F.; Garcia de Jalon, A.; Ramirez, L.; Olano, X.; Bernad, I.; Erice, R.

    2008-07-01

    In this paper we will show the results of the analysis of factors that influence the estimation of optical efficiency of solar thermal collectors testes according to the European standard UNE-EN 12975-2. Indoor tests with solar simulator involve control of the spectrum of its lamps to ensure that the difference with the Sun one does not change the optical efficiency {eta}{sub 0} of the collector. For outdoor tests, the diffuse radiation should be control as well. In the laboratory (LCS) of CENER, solar collectors tests are done according to part 6.1 of the standard UNE{sub E}N 12975-2 in continuous solar simulator. This study estimated the spectral correction applied to the estimation of optical efficiency of some solar collectors, with different selective materials. Likewise, we will weight the influence of terms related to diffuse radiation and spectral distribution. (Author)

  9. Basic aspects for application of solar thermal energy: thermie programme action

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    This book presents the activities of the Thermie programme action on application of Solar thermal energy. The main aspects are: 1.- General Aspects of low temperature solar energy 2.- Case studies 2.1 Spain: Solar heating project at the Ipocampo Playa Hotel, Majorca 2.2 Denmark: egebjerggard III energy efficient building, Ballerup 2.3 France: solar hot water supply in the Bastia Hospital, Corsica 2.4 Germany: Vacuum collector for heat supply for a swimming pool in Perschen 2.5 Greece: Large solar systems technologies in Greece 2.6 Ireland: The green Building-Temple Bar, Dublin 2.7 Italy: Unglazed collectors for seasonal production of hot water-Riccione 2.8 The Netherlands: de Zwoer swimming pool, Driebergen 2.9 Portugal: Hot water production by use of solar energy in Monsanto camp site 2.10 Spain: Solar thermal installation for a single dwelling, Javea

  10. The Solar Thermal Design Assistance Center report of its activities and accomplishments in Fiscal Year 1993

    Energy Technology Data Exchange (ETDEWEB)

    Menicucci, D.F.

    1994-03-01

    The Solar Thermal Design Assistance Center (STDAC) at Sandia National Laboratories is a resource provided by the US Department of Energy`s Solar Thermal Program. Its major objectives are to accelerate the use of solar thermal systems through (a) direct technical assistance to users, (b) cooperative test, evaluation, and development efforts with private industry, and (c) educational outreach activities. This report outlines the major activities and accomplishments of the STDAC in Fiscal Year 1993. The report also contains a comprehensive list of persons who contacted the STDAC by telephone for information or technical consulting.

  11. A Study of Solar Thermal Propulsion System Enhancement via Thermal Storage and Thermal-electric Conversion

    Science.gov (United States)

    2010-03-24

    material. Molybdenum has a thermal conductivity of 138 W/mK, while rheniums is much lower at 39.6 W/mK 2 . Zirconium Boride (ZrB2) and Hafnium Boride ...14,000 Iridium 77 2739 213 147 $42,000 Niobium 41 2750 323 53.7 $170 Molybdenum 42 2896 390 138 $100 The materials listed in Table 1 do not...this paper, several materials with melting points above 3000 K are boride compounds and several of those that are not borides contain elements which

  12. Solar Power in the European Context: Conversion Efficiency and the Issue of Carbon

    Directory of Open Access Journals (Sweden)

    Henrique Silva Pacini Costa

    2009-04-01

    Full Text Available The European Union is committed to increasing the use of renewable energies across Europe. One of the ways this is to be done is through the promotion of solar photovoltaics (PV, a method with significant environmental benefits. However, the high costs of electricity generated through PV have constrained the market reach of this option. This paper takes the form of a policy discussion, analyzing the fundamental issues concerning this type of energy, and its place in the European alternative energy market. Furthermore, a scenario is drafted to estimate how efficient solar panels should ideally be to make electricity produced by them cost-competitive with conventional, grid-tied energy sources. The study considers both a conventional scenario and another, with carbon capture costs incorporated into the final electricity prices. It is observed that in order to be competitive with conventional fossil-based electricity, photovoltaic conversion efficiencies should be around 34%. Incorporating carbon costs would further help promote solar PV, making it more price-attractive compared to emission-intensive electricity generation based on fossil fuels. The final part of the paper sheds light on the new developments on European PV, mainly in regards to the 2008 European Commission Climate Change Package, its implications and reactions from the industry.

  13. Modeling and performance simulation of 100 MW LFR based solar thermal power plant in Udaipur India

    Directory of Open Access Journals (Sweden)

    Deepak Bishoyi

    2017-12-01

    Full Text Available Solar energy is the most abundant source of energy on the earth and considered as an important alternative to fossil fuels. Solar energy can be converted into electric energy by using two different processes: photovoltaic conversion and the thermodynamic cycles. Lifetime and efficiency of PV power plant is lesser as compared to the CSP technology. CSP technology is viewed as one of the most promising alternative technology in the field of solar energy utilization. A 100 MW Linear Fresnel Reflector solar thermal power plant design with 6 hours of thermal energy storage has been evaluated for thermal performance using NREL SAM. A location receiving an annual DNI of 2248.17 kWh/m2/year in Rajasthan is chosen for the technical feasibility of hypothetical CSP plant. The plant design consists of 16 numbers of solar collector modules in a loop. HITEC solar salt is chosen as an HTF due to its excellent thermodynamic properties. The designed plant can generate annual electricity of 263,973,360 kWh with the plant efficiency of 18.3 %. The capacity utilization of the proposed LFR plant is found to be 30.2%. The LFR solar thermal power plant performance results encourage further innovation and development of CSP plants in India. Keywords: Linear Fresnel Reflector (LFR solar thermal power plant, SAM (System Advisor Model, India

  14. Thermal Field Analysis and Simulation of an Infrared Belt Furnace Used for Solar Cells

    Directory of Open Access Journals (Sweden)

    Bai Lu

    2014-01-01

    Full Text Available During solar cell firing, volatile organic compounds (VOC and a small number of metal particles were removed using the gas flow. When the gas flow was disturbed by the thermal field of infrared belt furnace and structure, the metal particles in the discharging gas flow randomly adhered to the surface of solar cell, possibly causing contamination. Meanwhile, the gas flow also affected the thermal uniformity of the solar cell. In this paper, the heating mechanism of the solar cell caused by radiation, convection, and conduction during firing was analyzed. Afterward, four 2-dimensional (2D models of the furnace were proposed. The transient thermal fields with different gas inlets, outlets, and internal structures were simulated. The thermal fields and the temperature of the solar cell could remain stable and uniform when the gas outlets were installed at the ends and in the middle of the furnace, with the gas inlets being distributed evenly. To verify the results, we produced four types of furnaces according to the four simulated results. The experimental results indicated that the thermal distribution of the furnace and the characteristics of the solar cells were consistent with the simulation. These experiments improved the efficiency of the solar cells while optimizing the solar cell manufacturing equipment.

  15. Research and Development for Novel Thermal Energy Storage Systems (TES) for Concentrating Solar Power (CSP)

    Energy Technology Data Exchange (ETDEWEB)

    Faghri, Amir; Bergman, Theodore L; Pitchumani, Ranga

    2013-09-26

    The overall objective was to develop innovative heat transfer devices and methodologies for novel thermal energy storage systems for concentrating solar power generation involving phase change materials (PCMs). Specific objectives included embedding thermosyphons and/or heat pipes (TS/HPs) within appropriate phase change materials to significantly reduce thermal resistances within the thermal energy storage system of a large-scale concentrating solar power plant and, in turn, improve performance of the plant. Experimental, system level and detailed comprehensive modeling approaches were taken to investigate the effect of adding TS/HPs on the performance of latent heat thermal energy storage (LHTES) systems.

  16. Thermal chopper spectrometer for the European spallation source

    DEFF Research Database (Denmark)

    Klenø, Kaspar Hewitt; Lefmann, Kim

    2011-01-01

    One of the instruments being considered for the ESS is a thermal chopper spectrometer, intended for the study of lattice vibrations and magnetic excitations. However, as the ESS will be a long pulsed source, we propose a very long instrument (180–300 m). We here present a guide system that can...... achieve a flux of 3.47 ×108 n/(s·cm2) and a resolution of dE/E = 5.3% for 1 Å neutrons on the sample with a transport efficiency of 80%. Furthermore, we demonstrate the efficiency of the instrument using a virtual experiment measuring an elastic line width...

  17. Solar tests of aperture plate materials for solar thermal dish collectors

    Science.gov (United States)

    Jaffe, L. D.

    1984-01-01

    If a malfunction occurs in a solar thermal point-focus distributed receiver power plant while a concentrator is pointed at the sun, motion of the concentrator may stop. As the sun moves relative to the earth, the spot of concentrated sunlight then slowly walks off the receiver aperture, across the receiver face plate, and perhaps across adjacent portions of the concentrator. Intense local heating by the concentrated sunlight may damage or destroy these parts. The behavior of various materials under conditions simulating walk-off of a parabolic dish solar collector were evaluated. Each test consisted of exposure to concentrated sunlight at a peak flux density of about 7000 kW/square meter for 15 minutes. Types of materials tested included graphite, silicon carbide, silica, various silicates, alumina, zirconia, aluminum, copper, steel, and polytetrafluroethylene. The only material that neither cracked nor melted was grade G-90 graphite. Grade CS graphite, a lower cost commercial grade, cracked half-way across, but did not fail apart. Both of these grades are medium-grain extruded graphites. A graphite cloth (graphitized polyacrylonitrile) showed fair performance when tested as a single thin ply; it might be useful as a multi-ply assembly. High purity slipcast silica showed some promise also.

  18. Typology of the Solar thermal facilities of low temperature; Tipologia de instalaciones solares termicas de baja temperatura

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2008-07-01

    The public interest by sustain ability and the governmental support are in the base of the great number of solar thermal collectors installed during the last years. In fact, the new 2006 Building Technical Code, Very responsible for this development on 2007, has provoked the appearance of new design instruments to guarantee in the collectors his energetic efficiency, his architectural integration, his durability and his maintenance. This article checks the different types of solar collectors of low temperate. (Author)

  19. Process and Economic Optimisation of a Milk Processing Plant with Solar Thermal Energy

    DEFF Research Database (Denmark)

    Bühler, Fabian; Nguyen, Tuong-Van; Elmegaard, Brian

    2016-01-01

    . Based on the case study of a dairy factory, where first a heat integration is performed to optimise the system, a model for solar thermal process integration is developed. The detailed model is based on annual hourly global direct and diffuse solar radiation, from which the radiation on a defined...... surface is calculated. Based on hourly process stream data from the dairy factory, the optimal streams for solar thermal process integration are found, with an optimal thermal storagetank volume. The last step consists of an economic optimisation of the problem to determine the optimal size......This work investigates the integration of solar thermal systems for process energy use. A shift from fossil fuels to renewable energy could be beneficial both from environmental and economic perspectives, after the process itself has been optimised and efficiency measures have been implemented...

  20. Monitoring solar-thermal systems: An outline of methods and procedures

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, A. [New Mexico State Univ., Las Cruces, NM (United States). Southwest Technology Development Inst.

    1994-04-01

    This manual discusses the technical issues associated with monitoring solar-thermal systems. It discusses some successful monitoring programs that have been implemented in the past. It gives the rationale for selecting a program of monitoring and gives guidelines for the design of new programs. In this report, solar thermal monitoring systems are classified into three levels. For each level, the report discusses the kinds of information obtained by monitoring, the effort needed to support the monitoring program, the hardware required, and the costs involved. Ultimately, all monitoring programs share one common requirement: the collection of accurate data that characterize some aspect or aspects of the system under study. This report addresses most of the issues involved with monitoring solar thermal systems. It does not address such topics as design fundamentals of thermal systems or the relative merits of the many different technologies employed for collection of solar energy.

  1. Thermal performance evaluation of the Northrop model NSC-01-0732 concentrating solar collector array at outdoor conditions. [Marshall Space Flight Center solar house test facility

    Science.gov (United States)

    1979-01-01

    The thermal efficiency of the concentrating, tracking solar collector was tested after ten months of operation at the Marshall Space Flight Center solar house. The test procedures and results are presented.

  2. Thermal state of the Roer Valley Graben, part of the European Cenozoic Rift System

    NARCIS (Netherlands)

    Luijendijk, E.; ter Voorde, M.; van Balen, R.T.; Verweij, H.; Simmelink, E.

    2010-01-01

    We performed a detailed analysis of the thermal state of the Cenozoic Roer Valley Graben, the north-western branch of the European Cenozoic Rift System, based on a new set of temperature data. We developed a numerical technique for correcting bottom hole temperatures, including an evaluation of the

  3. Thermal state of the Roer Valley Graben, part of the European Cenozoic Rift System

    NARCIS (Netherlands)

    Luijendijk, E.; ter Voorde, M.; van Balen, R.T.; Verweij, H.; Simmelink, E.

    2011-01-01

    We performed a detailed analysis of the thermal state of the Cenozoic Roer Valley Graben, the north-western branch of the European Cenozoic Rift System, based on a new set of temperature data. We developed a numerical technique for correcting bottom hole temperatures, including an evaluation of the

  4. Solar thermal and natural gas: an efficient complementarity; Solaire thermique et gaz naturel: une complementarite performante

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-10-01

    This document summarizes the content of a conference-debate organized by Cegibat, the information service of Gaz de France for building engineering professionals, about the complementarity between natural gas and solar thermal energies, in particular for the production of domestic hot water: 1 - the market of solar thermal energy in France (development, energy efficiency, different technical solutions, financial help, questions and answers with the public); 2 - the 'Dolce Vita' solar offer for individual houses (customers expectations, available techniques, fitter's testimony, questions and answers with the public); 3 - presentation of a combines solar system: the direct solar floor; 4 - the domestic solar hot water offer 'Dolce Vita'; 5 -testimonies; 6 - results warranty; 7 - conclusion. (J.S.)

  5. Indoor test for thermal performance of the Sunmaster evacuated tube (liquid) solar collector

    Science.gov (United States)

    1979-01-01

    The test procedures used to obtain the thermal performance data for a solar collector under simulated conditions are presented. Tests included a stagnation test, a time constant test, a thermal efficiency test, an incident angle modifier test, and a hot fill test. All tests were performed at ambient conditions and the transient effect and the incident angle effect on the collector were determined. The solar collector is a water working fluid type.

  6. Construction and initial operation of the combined solar thermal and electric desiccant cooling system

    Energy Technology Data Exchange (ETDEWEB)

    Enteria, Napoleon; Yoshino, Hiroshi; Mochida, Akashi; Takaki, Rie [Graduate School of Engineering, Tohoku University, Sendai 980-8579 (Japan); Satake, Akira [Technical Research Institute, Maeda Corporation, Tokyo 179-8914 (Japan); Yoshie, Ryuichiro [Faculty of Engineering, Tokyo Polytechnic University, Atsugi 243-0297 (Japan); Mitamura, Teruaki [Faculty of Engineering, Ashikaga Institute of Technology, Ashikaga 326-8558 (Japan); Baba, Seizo [Earth Clean Tohoku Co., Ltd., Sendai 984-0038 (Japan)

    2009-08-15

    This paper reports the constructed combined solar thermal and electric desiccant cooling system - its initial operation and operational procedures. The system, as designed, can be operated during nighttime and daytime. The nighttime operation is for thermal energy storage using the auxiliary electric heater, while the daytime operation is for solar energy collection and desiccant cooling. Ongoing experimental evaluation is being undertaken to observe and determine the long-term performance of the system. (author)

  7. Hierarchical Graphene Foam for Efficient Omnidirectional Solar-Thermal Energy Conversion.

    Science.gov (United States)

    Ren, Huaying; Tang, Miao; Guan, Baolu; Wang, Kexin; Yang, Jiawei; Wang, Feifan; Wang, Mingzhan; Shan, Jingyuan; Chen, Zhaolong; Wei, Di; Peng, Hailin; Liu, Zhongfan

    2017-10-01

    Efficient solar-thermal energy conversion is essential for the harvesting and transformation of abundant solar energy, leading to the exploration and design of efficient solar-thermal materials. Carbon-based materials, especially graphene, have the advantages of broadband absorption and excellent photothermal properties, and hold promise for solar-thermal energy conversion. However, to date, graphene-based solar-thermal materials with superior omnidirectional light harvesting performances remain elusive. Herein, hierarchical graphene foam (h-G foam) with continuous porosity grown via plasma-enhanced chemical vapor deposition is reported, showing dramatic enhancement of broadband and omnidirectional absorption of sunlight, which thereby can enable a considerable elevation of temperature. Used as a heating material, the external solar-thermal energy conversion efficiency of the h-G foam impressively reaches up to ≈93.4%, and the solar-vapor conversion efficiency exceeds 90% for seawater desalination with high endurance. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. The Effect of Booster-Mirror Reflector on the Thermal Performance of a Truncated Pyramid Solar Thermal Cooker

    OpenAIRE

    I. L. Mohammed; Aliyu, M. M.

    2014-01-01

    In this paper, the results and analysis of the performance of a truncated pyramid solar thermal cooker under two conditions are presented: booster-mirror reflector covered with black cloth, and booster-mirror reflector exposed to solar radiation. Results of the thermal performance tests show respective stagnation absorber plate temperatures of 145 oC and 137 oC. First/Second Figures of Merit are 0.120/0.346 and 0.125/0.400 respectively. The total heating times of 5.2 kg of wate...

  9. Thermal power systems small power systems application project: Siting issues for solar thermal power plants with small community applications

    Science.gov (United States)

    Holbeck, H. J.; Ireland, S. J.

    1979-01-01

    The siting issues associated with small, dispersed solar thermal power plants for utility/small community applications of less than 10 MWe are reported. Some specific requirements are refered to the first engineering experiment for the Small Power Systems Applications (SPSA) Project. The background for the subsequent issue discussions is provided. The SPSA Project and the requirements for the first engineering experiment are described, and the objectives and scope for the report as a whole. A overview of solar thermal technologies and some technology options are discussed.

  10. Solar Thermal Upper Stage Liquid Hydrogen Pressure Control Testing

    Science.gov (United States)

    Moore, J. D.; Otto, J. M.; Cody, J. C.; Hastings, L. J.; Bryant, C. B.; Gautney, T. T.

    2015-01-01

    High-energy cryogenic propellant is an essential element in future space exploration programs. Therefore, NASA and its industrial partners are committed to an advanced development/technology program that will broaden the experience base for the entire cryogenic fluid management community. Furthermore, the high cost of microgravity experiments has motivated NASA to establish government/aerospace industry teams to aggressively explore combinations of ground testing and analytical modeling to the greatest extent possible, thereby benefitting both industry and government entities. One such team consisting of ManTech SRS, Inc., Edwards Air Force Base, and Marshall Space Flight Center (MSFC) was formed to pursue a technology project designed to demonstrate technology readiness for an SRS liquid hydrogen (LH2) in-space propellant management concept. The subject testing was cooperatively performed June 21-30, 2000, through a partially reimbursable Space Act Agreement between SRS, MSFC, and the Air Force Research Laboratory. The joint statement of work used to guide the technical activity is presented in appendix A. The key elements of the SRS concept consisted of an LH2 storage and supply system that used all of the vented H2 for solar engine thrusting, accommodated pressure control without a thermodynamic vent system (TVS), and minimized or eliminated the need for a capillary liquid acquisition device (LAD). The strategy was to balance the LH2 storage tank pressure control requirements with the engine thrusting requirements to selectively provide either liquid or vapor H2 at a controlled rate to a solar thermal engine in the low-gravity environment of space operations. The overall test objective was to verify that the proposed concept could enable simultaneous control of LH2 tank pressure and feed system flow to the thruster without necessitating a TVS and a capillary LAD. The primary program objectives were designed to demonstrate technology readiness of the SRS concept

  11. Application of field-modulated generator systems to dispersed solar thermal electric generation

    Science.gov (United States)

    Ramakumar, R.

    1979-01-01

    The state-of-the-art of field modulated generation system (FMGS) is presented, and the application of FMGS to dispersed solar thermal electric generation is discussed. The control and monitoring requirements for solar generation system are defined. A comparison is presented between the FMGS approach and other options and the technological development needs are discussed.

  12. Aging and corrosion problems of plane thermal solar collectors: literature and field investigations

    Energy Technology Data Exchange (ETDEWEB)

    Wennerholm, H.; Lagerkvist, K.U.

    1979-01-01

    The literature and field investigation will be the basis of a project concerning the development of standardized methods for the test of solar collectors which are used in heating and cooling systems. The literature and field investigations include the study of the construction of plane thermal solar collectors as well as atmospheric degradation processes on different construction materials.

  13. Thermal destratification in small standard solar tanks due to mixing during tapping

    DEFF Research Database (Denmark)

    Andersen, Elsa; Furbo, Simon

    1999-01-01

    The aim of the project is to investigate the thermal destratification in small standard solar tanks due to mixing during tapping. Three different cold water inlet designs are tested. A model of the tested solar tank is verified. Based on the measurements and the calculations it is elucidated how...

  14. Parametric analysis of a high temperature packed bed thermal storage design for a solar gas turbine

    CSIR Research Space (South Africa)

    Klein, P

    2015-08-01

    Full Text Available The development of a high temperature Thermal Energy Storage (TES) system will allow for high solar shares in Solar Gas Turbine (SGT) plants. In this research a pressurised storage solution is proposed that utilises a packed bed of alumina spheres...

  15. Development of Proposed Standards for Testing Solar Collectors and Thermal Storage Devices. NBS Technical Note 899.

    Science.gov (United States)

    Hill, James E.; And Others

    A study has been made at the National Bureau of Standards of the different techniques that are or could be used for testing solar collectors and thermal storage devices that are used in solar heating and cooling systems. This report reviews the various testing methods and outlines a recommended test procedure, including apparatus and…

  16. Design, Fabrication, and Efficiency Study of a Novel Solar Thermal Water Heating System: Towards Sustainable Development

    Directory of Open Access Journals (Sweden)

    M. Z. H. Khan

    2016-01-01

    Full Text Available This paper investigated a novel loop-heat-pipe based solar thermal heat-pump system for small scale hot water production for household purposes. The effective use of solar energy is hindered by the intermittent nature of its availability, limiting its use and effectiveness in domestic and industrial applications especially in water heating. The easiest and the most used method is the conversion of solar energy into thermal energy. We developed a prototype solar water heating system for experimental test. We reported the investigation of solar thermal conversion efficiency in different seasons which is 29.24% in summer, 14.75% in winter, and 15.53% in rainy season. This paper also discusses the DC heater for backup system and the current by using thermoelectric generator which are 3.20 V in summer, 2.120 V in winter, and 1.843 V in rainy season. This solar water heating system is mostly suited for its ease of operation and simple maintenance. It is expected that such novel solar thermal technology would further contribute to the development of the renewable energy (solar driven heating/hot water service and therefore lead to significant environmental benefits.

  17. Solar production of catalytic filamentous carbon by thermal decomposition of hydrocarbons and carbon monoxide

    Energy Technology Data Exchange (ETDEWEB)

    Kirillov, V.A.; Kuvshinov, G.G.; Mogilnykh, Yu.I. [Boreskov Institute of Catalysis, Novosibirsk (Russian Federation); Reller, A. [University of Hamburg (Germany); Steinfeld, A.; Weidenkaff, A.; Meier, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    Concentrated solar radiation was used as the clean source of process heat for the production of Catalytic Filamentous Carbon (CFC) by thermal decomposition of gaseous hydrocarbons and by CO disproportionation in the presence of small metal catalyst particles. Depending on the catalyst, two different types of CFC, namely nano tubes and nano fibers, were obtained in solar experiments at the PSI solar furnace. (author) 2 figs., 1 tab., 7 refs.

  18. Unglazed transpired solar collector having a low thermal-conductance absorber

    Science.gov (United States)

    Christensen, Craig B.; Kutscher, Charles F.; Gawlik, Keith M.

    1997-01-01

    An unglazed transpired solar collector using solar radiation to heat incoming air for distribution, comprising an unglazed absorber formed of low thermal-conductance material having a front surface for receiving the solar radiation and openings in the unglazed absorber for passage of the incoming air such that the incoming air is heated as it passes towards the front surface of the absorber and the heated air passes through the openings in the absorber for distribution.

  19. Report on the symposium and workshop on the 5 MWt solar thermal test facility

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    Design concepts and applications for the 5 MWt Solar Thermal Test Facility at Albuquerque are discussed in 43 papers. Session topics include central receivers, solar collectors, solar energy storage, high temperature materials and chemistry. A program overview and individual contractor reports for the test facility project are included, along with reports on conference workshop sessions and users group recommendations. A list of conference attendees is appended. Separate abstracts are prepared for 39 papers.

  20. Graphene-enhanced thermal interface materials for heat removal from photovoltaic solar cells

    Science.gov (United States)

    Saadah, M.; Gamalath, D.; Hernandez, E.; Balandin, A. A.

    2016-09-01

    The increase in the temperature of photovoltaic (PV) solar cells affects negatively their power conversion efficiency and decreases their lifetime. The negative effects are particularly pronounced in concentrator solar cells. Therefore, it is crucial to limit the PV cell temperature by effectively removing the excess heat. Conventional thermal phase change materials (PCMs) and thermal interface materials (TIMs) do not possess the thermal conductivity values sufficient for thermal management of the next generation of PV cells. In this paper, we report the results of investigation of the increased efficiency of PV cells with the use of graphene-enhanced TIMs. Graphene reveals the highest values of the intrinsic thermal conductivity. It was also shown that the thermal conductivity of composites can be increased via utilization of graphene fillers. We prepared TIMs with up to 6% of graphene designed specifically for PV cell application. The solar cells were tested using the solar simulation module. It was found that the drop in the output voltage of the solar panel under two-sun concentrated illumination can be reduced from 19% to 6% when grapheneenhanced TIMs are used. The proposed method can recover up to 75% of the power loss in solar cells.

  1. Solar thermal energy for supplemental heat to process tea in Sri Lanka

    Energy Technology Data Exchange (ETDEWEB)

    Ariyaratne, A.R.

    1987-01-01

    In tea processing, the subprocesses of withering and drying require thermal energy for dehydration of tea leaves. At present, the Sri Lankan tea industry depends mostly on imported fossil fuels for its thermal energy needs. The economic pressure has forced the industry to investigate energy alternatives. In this study solar thermal energy, heat recovery from fluidized-bed dryers, and a combination of solar system with heat recovery were analyzed. The /phi/, f-chart general design method was used to design solar systems to match thermal energy needs in tea processing. The analysis was extended to the f-chart economic analysis to select economically optimum systems. On the basis of highest life-cycle savings, flat-plate solar-collector area and storage tank were sized. Results showed that solar thermal systems require a high investment,but can provide 42, 52, and 63% of the energy needs for high, mid and low tea growing regions, respectively. Combination of solar thermal systems with heat recovery from a fluidized-bed dryer decreases the amount of energy required by another 7 to 12% yet requires only a small increase in investment.

  2. GIS methodology and case study regarding assessment of the solar potential at territorial level: PV or thermal?

    Directory of Open Access Journals (Sweden)

    Loïc Quiquerez

    2015-06-01

    Full Text Available This paper presents a GIS-based methodology for assessing solar photovoltaic (PV and solar thermal potentials in urban environment. The consideration of spatial and temporal dimensions of energy resource and demand allows, for two different territories of the Geneva region, to determine the suitable building roof areas for solar installations, the solar irradiance on these areas and, finally, the electrical and/or thermal energy potentials related to the demand. Results show that the choice of combining PV and solar thermal for domestic hot water (DHW is relevant in both territories. Actually, the installation of properly sized solar thermal collectors doesn’t decrease much the solar PV potential, while allowing significant thermal production. However, solar collectors for combined DHW and space heating (SH require a much larger surface and, therefore, have a more important influence on the PV potential.

  3. A model for managing and evaluating solar radiation for indoor thermal comfort

    Energy Technology Data Exchange (ETDEWEB)

    La Gennusa, Maria; Rizzo, Gianfranco [Dipartimento di Ricerche Energetiche ed Ambientali (DREAM), Universita degli Studi di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Nucara, Antonino; Pietrafesa, Matilde [Dipartimento di Informatica, Matematica, Elettronica e Trasporti (DIMET), Universita Mediterranea di Reggio Calabria, Feo di Vito, 89060 Reggio Calabria (Italy)

    2007-05-15

    Thermal comfort of people occupying indoor spaces depends, to a large extent, on the direct component of solar radiation incident on the human body. In turn, even the diffuse component of the solar radiation could affect the thermal sensations of people. Despite this evidence, at the present there is a lack in the availability of simple and reliable methods capable of taking into account the influence of the solar radiation on thermal balance in the human body. In this work a comprehensive method is presented for the computation of the mean radiant temperature of people in thermal moderate indoor environments in the presence of solar radiation. The effects produced on the amount of solar radiation entering rooms in the presence of shadowing devices are also analysed. Finally, an application of the method is provided for a non-parallelepiped room equipped with a south window: results are shown in terms of the mean radiant temperature. A simple evaluation of thermal comfort conditions, referring to the present international standards, is also provided. The model can be easily linked to the computerized methods for analyzing the thermal behaviour of buildings, and is intended as a support for the thermal comfort evaluation methods. (author)

  4. Assessment of the potential of solar thermal small power systems in small utilities

    Science.gov (United States)

    Steitz, P.; Mayo, L. G.; Perkins, S. P., Jr.

    1978-01-01

    The potential economic benefit of small solar thermal electric power systems to small municipal and rural electric utilities is assessed. Five different solar thermal small power system configurations were considered in three different solar thermal technologies. The configurations included: (1) 1 MW, 2 MW, and 10 MW parabolic dish concentrators with a 15 kW heat engine mounted at the focal point of each dish, these systems utilized advanced battery energy storage; (2) a 10 MW system with variable slat concentrators and central steam Rankine energy conversion, this system utilized sensible thermal energy storage; and (3) a 50 MW central receiver system consisting of a field of heliostats concentrating energy on a tower-mounted receiver and a central steam Rankine conversion system, this system also utilized sensible thermal storage. The results are summarized in terms of break-even capital costs. The break-even capital cost was defined as the solar thermal plant capital cost which would have to be achieved in order for the solar thermal plants to penetrate 10 percent of the reference small utility generation mix by the year 2000. The calculated break-even capital costs are presented.

  5. Experimental investigation into a packed bed thermal storage solution for solar gas turbine systems

    CSIR Research Space (South Africa)

    Klein, P

    2013-09-01

    Full Text Available High temperature thermal storage in randomly packed beds of ceramic particles is proposed as an effective storage solution for Solar Gas Turbine (SGT) cycles in the near term. Numerical modelling of these systems allows for optimised thermal storage...

  6. Efficient solar-driven synthesis, carbon capture, and desalinization, STEP: solar thermal electrochemical production of fuels, metals, bleach.

    Science.gov (United States)

    Licht, S

    2011-12-15

    STEP (solar thermal electrochemical production) theory is derived and experimentally verified for the electrosynthesis of energetic molecules at solar energy efficiency greater than any photovoltaic conversion efficiency. In STEP the efficient formation of metals, fuels, chlorine, and carbon capture is driven by solar thermal heated endothermic electrolyses of concentrated reactants occuring at a voltage below that of the room temperature energy stored in the products. One example is CO(2) , which is reduced to either fuels or storable carbon at a solar efficiency of over 50% due to a synergy of efficient solar thermal absorption and electrochemical conversion at high temperature and reactant concentration. CO(2) -free production of iron by STEP, from iron ore, occurs via Fe(III) in molten carbonate. Water is efficiently split to hydrogen by molten hydroxide electrolysis, and chlorine, sodium, and magnesium from molten chlorides. A pathway is provided for the STEP decrease of atmospheric carbon dioxide levels to pre-industial age levels in 10 years. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Real-Time System Application in Solar Thermal Plants

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez, J.; Yebra, L. J.; Valverde, A.; Berenguel, M.; Peralta, M.

    2006-07-01

    Activities performed in solar plants usually generate solar radiation concentrations. Those concentrations can reach very high temperatures, so errors calculating the positions where the concentrations must aim or exceeding the time when those positions must be supplied, can cause damage in people or in radiated components. The designs of certain applications in solar plants must be done using Real-Time System perspective to meet time and safety requirements. In the article we describe how we are implementing an application used in a solar plant to meet time and safety requirements. (Author)

  8. Calculation facility. Solar thermal low-temperature; Calculo de una instalacion. Energia solar termica de baja temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Comes, P.

    2010-07-01

    The aim of this paper is to express in a simple procedure to follow for the calculation of a solar thermal installation of low temperature. It will take as a model for an installation in operation Ariston washing a tunnel Sant Carles de la Rapita Tarragona. (Author)

  9. Yearly thermal performances of solar heating plants in Denmark – Measured and calculated

    DEFF Research Database (Denmark)

    Furbo, Simon; Dragsted, Janne; Perers, Bengt

    2018-01-01

    The thermal performance of solar collector fields depends mainly on the mean solar collector fluid temperature of the collector field and on the solar radiation. For Danish solar collector fields for district heating the measured yearly thermal performances per collector area varied in the period...... 2012–2016 between 313 kWh/m2 and 577 kWh/m2, with averages between 411 kWh/m2 and 463 kWh/m2. The percentage difference between the highest and lowest measured yearly thermal performance is about 84%. Calculated yearly thermal performances of typically designed large solar collector fields at six...... different locations in Denmark with measured weather data for the years 2002–2010 vary between 405 kWh/m2 collector and 566 kWh/m2 collector, if a mean solar collector fluid temperature of 60 °C is assumed. This corresponds to a percentage difference between the highest and lowest calculated yearly thermal...

  10. High-performance flat-panel solar thermoelectric generators with high thermal concentration.

    Science.gov (United States)

    Kraemer, Daniel; Poudel, Bed; Feng, Hsien-Ping; Caylor, J Christopher; Yu, Bo; Yan, Xiao; Ma, Yi; Wang, Xiaowei; Wang, Dezhi; Muto, Andrew; McEnaney, Kenneth; Chiesa, Matteo; Ren, Zhifeng; Chen, Gang

    2011-05-01

    The conversion of sunlight into electricity has been dominated by photovoltaic and solar thermal power generation. Photovoltaic cells are deployed widely, mostly as flat panels, whereas solar thermal electricity generation relying on optical concentrators and mechanical heat engines is only seen in large-scale power plants. Here we demonstrate a promising flat-panel solar thermal to electric power conversion technology based on the Seebeck effect and high thermal concentration, thus enabling wider applications. The developed solar thermoelectric generators (STEGs) achieved a peak efficiency of 4.6% under AM1.5G (1 kW m(-2)) conditions. The efficiency is 7-8 times higher than the previously reported best value for a flat-panel STEG, and is enabled by the use of high-performance nanostructured thermoelectric materials and spectrally-selective solar absorbers in an innovative design that exploits high thermal concentration in an evacuated environment. Our work opens up a promising new approach which has the potential to achieve cost-effective conversion of solar energy into electricity. © 2011 Macmillan Publishers Limited. All rights reserved

  11. Standard Practice for Evaluating Thermal Insulation Materials for Use in Solar Collectors

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1994-01-01

    1.1 This practice sets forth a testing methodology for evaluating the properties of thermal insulation materials to be used in solar collectors with concentration ratios of less than 10. Tests are given herein to evaluate the pH, surface burning characteristics, moisture adsorption, water absorption, thermal resistance, linear shrinkage (or expansion), hot surface performance, and accelerated aging. This practice provides a test for surface burning characteristics but does not provide a methodology for determining combustibility performance of thermal insulation materials. 1.2 The tests shall apply to blanket, rigid board, loose-fill, and foam thermal insulation materials used in solar collectors. Other thermal insulation materials shall be tested in accordance with the provisions set forth herein and should not be excluded from consideration. 1.3 The assumption is made that elevated temperature, moisture, and applied stresses are the primary factors contributing to the degradation of thermal insulation mat...

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

    Science.gov (United States)

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

    1980-11-01

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

  13. A Technical Note on Fabrication and Thermal Performance Studies of a Solar Pond Model

    Directory of Open Access Journals (Sweden)

    Abhishek Saxena

    2013-01-01

    Full Text Available A solar pond has been fabricated to analyze the thermal behavior of it, in the climatic conditions of Moradabad, Uttar Pradesh. Sodium chloride (NaCl has been used to form a salt gradient for better performance, and a dark-colored (blackened rigid surface bottom with 1 mm irregularities has been considered for trapping the heat in a good amount. A solar pond with a surface area of 2.56 m2 and a depth of 1 m has been filled with salty water of various densities to form three salty water zones (upper convective, nonconvective, and heat storage. A few investigations have been carried out to evaluate the thermal efficiencies of three different zones of the solar pond. An attempt is also made to improve the thermal performance of the salt gradient solar pond.

  14. Development and construction of the novel solar thermal desiccant cooling system incorporating hot water production

    Energy Technology Data Exchange (ETDEWEB)

    Enteria, Napoleon; Yoshino, Hiroshi; Mochida, Akashi; Takaki, Rie [Faculty of Engineering, Tohoku University, Sendai 980-8579 (Japan); Satake, Akira [Technical Research Institute, Maeda Corporation, Tokyo 179-8914 (Japan); Yoshie, Ryuichiro [Faculty of Engineering, Tokyo Polytechnic University, Atsugi 243-0297 (Japan); Baba, Seizo [Earth Clean Tohoku Co. Ltd., Sendai 984-0038 (Japan)

    2010-02-15

    This paper reports the development and construction of the novel solar cooling and heating system. The system consists of the thermal energy subsystem and the desiccant cooling subsystem. The system utilizes both the cheaper nighttime electric energy and the free daytime solar energy. The system is conceptualized to produce both cooling during summer daytime and hot water production during winter. Testing and evaluation of the system had been done to determine its operational procedure and performance. Based on the results, the thermal energy subsystem functioned to its expected performance in solar energy collection and thermal storage. The desiccant cooling subsystem reduced both the temperature and the humidity content of the air using solar energy with a minimal amount of back-up electric energy. The system however, needs further investigation under real conditions. (author)

  15. Optimization of Norbornadiene Compounds for Solar Thermal Storage by First-Principles Calculations.

    Science.gov (United States)

    Kuisma, Mikael; Lundin, Angelica; Moth-Poulsen, Kasper; Hyldgaard, Per; Erhart, Paul

    2016-07-21

    Molecular photoswitches capable of storing solar energy are interesting candidates for future renewable energy applications. Here, using quantum mechanical calculations, we carry out a systematic screening of crucial optical (solar spectrum match) and thermal (storage energy density) properties of 64 such compounds based on the norbornadiene-quadricyclane system. Whereas a substantial number of these molecules reach the theoretical maximum solar power conversion efficiency, this requires a strong red-shift of the absorption spectrum, which causes undesirable absorption by the photoisomer as well as reduced thermal stability. These compounds typically also have a large molecular mass, leading to low storage densities. By contrast, single-substituted systems achieve a good compromise between efficiency and storage density, while avoiding competing absorption by the photo-isomer. This establishes guiding principles for the future development of molecular solar thermal storage systems. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Economic optimization of a Kalina cycle for a parabolic trough solar thermal power plant

    DEFF Research Database (Denmark)

    Modi, Anish; Kærn, Martin Ryhl; Andreasen, J. G.

    2015-01-01

    technology for the conversion of solar thermal energy into electricity. In this paper, a Kalina cycle and a steam Rankine cycle are compared in terms of the total capital investment cost for use in a parabolic trough solar thermal power plant without storage. In order to minimize the total capital investment...... cost of the Kalina cycle power plant (the solar field plus the power cycle), an optimization was performed by varying the turbine outlet pressure, the separator inlet temperature and the separator inlet ammonia mass fraction. All the heat exchangers were modelled as shell and tube type using suitable......The Kalina cycle has recently seen increased interest as a replacement for the more traditional steam Rankine cycle for geothermal, solar, ocean thermal energy conversion and waste heat recovery applications. The Kalina cycle uses a mixture of ammonia and water as the working fluid. The ammonia...

  17. Experimental Study on Solar Cooling Tube Using Thermal/Vacuum Emptying Method

    Directory of Open Access Journals (Sweden)

    Huizhong Zhao

    2012-01-01

    Full Text Available A solar cooling tube using thermal/vacuum emptying method was experimentally studied in this paper. The coefficient of performance (COP of the solar cooling tube was mostly affected by the vacuum degree of the system. In past research, the thermal vacuum method, using an electric oven and iodine-tungsten lamp to heat up the adsorbent bed and H2O vapor to expel the air from the solar cooling tube, was used to manufacture solar cooling tubes. This paper presents a novel thermal vacuum combined with vacuum pump method allowing an increased vacuum state for producing solar cooling tubes. The following conclusions are reached: the adsorbent bed temperature of solar cooling tube could reaches up to 233°C, and this temperature is sufficient to meet desorption demand; the refrigerator power of a single solar cooling tube varies from 1 W to 12 W; the total supply refrigerating capacity is about 287 kJ; and the COP of this solar cooling tube is about 0.215.

  18. Limits to solar power conversion efficiency with applications to quantum and thermal systems

    Science.gov (United States)

    Byvik, C. E.; Buoncristiani, A. M.; Smith, B. T.

    1983-01-01

    An analytical framework is presented that permits examination of the limit to the efficiency of various solar power conversion devices. Thermodynamic limits to solar power efficiency are determined for both quantum and thermal systems, and the results are applied to a variety of devices currently considered for use in space systems. The power conversion efficiency for single-threshold energy quantum systems receiving unconcentrated air mass zero solar radiation is limited to 31 percent. This limit applies to photovoltaic cells directly converting solar radiation, or indirectly, as in the case of a thermophotovoltaic system. Photoelectrochemical cells rely on an additional chemical reaction at the semiconductor-electrolyte interface, which introduces additional second-law demands and a reduction of the solar conversion efficiency. Photochemical systems exhibit even lower possible efficiencies because of their relatively narrow absorption bands. Solar-powered thermal engines in contact with an ambient reservoir at 300 K and operating at maximum power have a peak conversion efficiency of 64 percent, and this occurs for a thermal reservoir at a temperature of 2900 K. The power conversion efficiency of a solar-powered liquid metal magnetohydrodydnamic generator, a solar-powered steam turbine electric generator, and an alkali metal thermoelectric converter is discussed.

  19. Energy comparison between solar thermal power plant and photovoltaic power plant

    Science.gov (United States)

    Novosel, Urška; Avsec, Jurij

    2017-07-01

    The combined use of renewable energy and alternative energy systems and better efficiency of energy devices is a promising approach to reduce effects due to global warming in the world. On the basis of first and second law of thermodynamics we could optimize the processes in the energy sector. The presented paper shows the comparison between solar thermal power plant and photovoltaic power plant in terms of energy, exergy and life cycle analysis. Solar thermal power plant produces electricity with basic Rankine cycle, using solar tower and solar mirrors to produce high fluid temperature. Heat from the solar system is transferred by using a heat exchanger to Rankine cycle. Both power plants produce hydrogen via electrolysis. The paper shows the global efficiency of the system, regarding production of the energy system.

  20. Cacao roasting in rural areas of Peru using concentrated solar thermal energy: experimental results

    Directory of Open Access Journals (Sweden)

    Veynandt François

    2016-01-01

    Full Text Available Solar food processing is gaining interest for income generation. Our solar cacao roaster, designed for rural areas, consists in a horizontal rotating drum, opened at one end to collect solar radiation from Scheffler concentrators of 2.7 or 8 m2. The experimental results presented bring knowledge on the system's behavior and optimal operation. The influence of the most significant parameters is studied: quantity of cacao, absorptivity of drum's coating, thermal insulation, inclination and rotational speed of the drum. Cacao temperature and direct solar irradiance are monitored to evaluate the performance in roasting time per kilogram of cacao.

  1. Optical and thermal characterization of membrane reflector materials for solar orbit transfer vehicles

    Science.gov (United States)

    Farmer, Gregory D.; McGee, Jennie K.; Partch, Russell; Lester, Dean M.

    2002-01-01

    The Air Force Research Laboratory (AFRL), is advancing technologies to enable greater mobility for future AF spacecraft. The Solar Orbit Transfer Vehicle (SOTV) program is developing components for a concept based on a solar thermal rocket and solar thermal power generation. The program is performing ground testing of a thin film membrane concentrator concept. To better understand system performance, a series of optical characterization tests of the membrane material were performed. The objective was to quantify the relationship between membrane optical properties and the concentrator on-orbit transmission performance and thermal profile. During testing we collected reflectivity, absorptivity, transmissivity, and emissivity data for un-coated and coated membrane material. The membrane material tested was fabricated using a flight-qualified polyimide material and proven manufacturing processes. The test results, and system thermal analysis are presented in this paper. The results of this research will be used to refine hardware performance predictions and improve sizing for flight demonstration. .

  2. The active thermal solar; Le solaire thermique actif

    Energy Technology Data Exchange (ETDEWEB)

    Bedel, St.; Salomon, Th.

    2000-05-01

    This information paper recalls the different types of solar cells and their operating. It presents the possible utilizations for the buildings heating (air and water systems) and for the water heating in the residential houses (also for the heating of swimming pools) and the collective buildings. The drying of agricultural products and the solar cooling are also discussed. (A.L.B.)

  3. Thermal analysis of solar dryers | Assefa | Zede Journal

    African Journals Online (AJOL)

    Results of the system simulation are presented in graphical fonn suitable for system pe1formance detennination. From the incident solar flux, ambient air temperature and solar collector parameters, the average yearly values of useful energy, the collector outlet air-temperature and air volume flow-rate are also predicted and ...

  4. Thermal utilisation of solar energy: Croatian National Energy Program SUNEN, 1998-2010

    Energy Technology Data Exchange (ETDEWEB)

    Frankovic, Bernard; Jedrisko, Claudia [Rijeka Univ., Faculty of Engineering, Rijeka (Croatia); Hrastnik, Branimir [Energy Inst. `Hrvoje Pozar`, Zagreb (Croatia)

    1999-01-01

    In the paper, thermal use of solar energy as well as prospects and problems of its utilisation in Croatia have been given. The National Solar Energy Program, SUNEN, has been established to stimulate the usage of solar energy. The main goals of the program are the assessment of technical and economically viable solar potential in order to define real objectives and tasks to provide use of exploitable indigenous clean and renewable energy potential. The Program addresses benefits, the most promising solar applications and solar potential. Much attention has been given to identification of obstacles and barriers in the process of solar technology dissemination. SUNEN is an initiative to increase solar energy use and to become more compatible with the present renewable energy sources policy in EU and Mediterranean countries. The program proposes twelve different types of thermal solar energy systems, which could be multiplied up to 28 000 installations until the year 2010 with annual heat recovery of approximately 1,5 TWh (5,4 PJ). (Author)

  5. GIS methodology and case study regarding assessment of the solar potential at territorial level: PV or thermal?

    OpenAIRE

    Loïc Quiquerez; Jérôme Faessler; Bernard Marie Lachal; Floriane Mermoud; Pierre Hollmuller

    2015-01-01

    This paper presents a GIS-based methodology for assessing solar photovoltaic (PV) and solar thermal potentials in urban environment. The consideration of spatial and temporal dimensions of energy resource and demand allows, for two different territories of the Geneva region, to determine the suitable building roof areas for solar installations, the solar irradiance on these areas and, finally, the electrical and/or thermal energy potentials related to the demand. Results show that the choice ...

  6. Polymeric compositional materials based on polycarbonate for units of devices for transform solar into thermal energy

    Directory of Open Access Journals (Sweden)

    V. I. Sytar

    2017-06-01

    Full Text Available Modern development of the industry is complicated without introduction of energy-saving technologies based on renewable natural energy sources. Solar and wind power plants, heat generators, solar collectors are wide spread in developed countries. One of it is device for transform solar into thermal energy. It is costly devices with low level of reliability and durability. Therefore actual tasks of this work are reduction cost of device for transform solar into thermal energy and increase it level of reliability and durability. These tasks are carried out by the way of substitution the main elements of device for transform solar into thermal energy by development polymeric compositional materials (PCM. As the polymer matrix is selected polycarbonate. This matrix is modified by silicon rubber and filled by graphite. The silicon rubber increase technological effectiveness by procedure of obtaining PCM. Graphite significantly increase tribotechnical properties of PCM in friction units with steel. Developed PCM can be recommended for application in main elements of device for transform solar into thermal energy, that lead to increasing of it level of reliability and durability.

  7. OSEA CanSIA solar thermal community action manual. Revision 2

    Energy Technology Data Exchange (ETDEWEB)

    Gill, S. [Ontario Sustainable Energy Association, Toronto, ON (Canada); Goldwater, A. [Goldwater Solar Services, Toronto, ON (Canada)

    2008-07-01

    Solar thermal energy is a type of energy generation that converts solar radiation into useable heat energy that is utilized on-site. Community power is a form of project ownership involving different residents of a community who pool their investment into a single or multiple renewable energy generation project. Two models have emerged as types of ownership structures. One structure provides for individual residential-scale systems through individual purchase or neighbourhood bulk-purchase, while the other involves remotely sited large installations for use by small communities or businesses, funded by local investment. This document presented a manual designed for residents of Canada who would like information on residential-scale, or small-scale commercial solar thermal installations, and information on initializing a community based organization situated in their neighbourhood. While the guide examined all ownership options, it focused primarily on community ownership. The manual provided information about currently available solar thermal technologies, and which technologies were best suited for various applications. The manual also discussed factors affecting the viability of a solar thermal project, such as site feasibility and regulatory issues. Ownership options were outlined, and a primer on financing solar thermal projects was provided. Last, the guide described the process of choosing a supplier and installer and addressed possible developments that will affect the future of solar thermal technology in Canada. It was concluded that community ownership has many benefits, including increasing public knowledge, reducing many of the risks associated with having an individual system, and reducing costs for individual users. refs., tabs., figs.

  8. Nanofluid Types, Their Synthesis, Properties and Incorporation in Direct Solar Thermal Collectors: A Review

    Science.gov (United States)

    Chamsa-ard, Wisut; Brundavanam, Sridevi; Fung, Chun Che; Fawcett, Derek; Poinern, Gerrard

    2017-01-01

    The global demand for energy is increasing and the detrimental consequences of rising greenhouse gas emissions, global warming and environmental degradation present major challenges. Solar energy offers a clean and viable renewable energy source with the potential to alleviate the detrimental consequences normally associated with fossil fuel-based energy generation. However, there are two inherent problems associated with conventional solar thermal energy conversion systems. The first involves low thermal conductivity values of heat transfer fluids, and the second involves the poor optical properties of many absorbers and their coating. Hence, there is an imperative need to improve both thermal and optical properties of current solar conversion systems. Direct solar thermal absorption collectors incorporating a nanofluid offers the opportunity to achieve significant improvements in both optical and thermal performance. Since nanofluids offer much greater heat absorbing and heat transfer properties compared to traditional working fluids. The review summarizes current research in this innovative field. It discusses direct solar absorber collectors and methods for improving their performance. This is followed by a discussion of the various types of nanofluids available and the synthesis techniques used to manufacture them. In closing, a brief discussion of nanofluid property modelling is also presented. PMID:28561802

  9. Nanofluid Types, Their Synthesis, Properties and Incorporation in Direct Solar Thermal Collectors: A Review.

    Science.gov (United States)

    Chamsa-Ard, Wisut; Brundavanam, Sridevi; Fung, Chun Che; Fawcett, Derek; Poinern, Gerrard

    2017-05-31

    The global demand for energy is increasing and the detrimental consequences of rising greenhouse gas emissions, global warming and environmental degradation present major challenges. Solar energy offers a clean and viable renewable energy source with the potential to alleviate the detrimental consequences normally associated with fossil fuel-based energy generation. However, there are two inherent problems associated with conventional solar thermal energy conversion systems. The first involves low thermal conductivity values of heat transfer fluids, and the second involves the poor optical properties of many absorbers and their coating. Hence, there is an imperative need to improve both thermal and optical properties of current solar conversion systems. Direct solar thermal absorption collectors incorporating a nanofluid offers the opportunity to achieve significant improvements in both optical and thermal performance. Since nanofluids offer much greater heat absorbing and heat transfer properties compared to traditional working fluids. The review summarizes current research in this innovative field. It discusses direct solar absorber collectors and methods for improving their performance. This is followed by a discussion of the various types of nanofluids available and the synthesis techniques used to manufacture them. In closing, a brief discussion of nanofluid property modelling is also presented.

  10. Nanofluid Types, Their Synthesis, Properties and Incorporation in Direct Solar Thermal Collectors: A Review

    Directory of Open Access Journals (Sweden)

    Wisut Chamsa-ard

    2017-05-01

    Full Text Available The global demand for energy is increasing and the detrimental consequences of rising greenhouse gas emissions, global warming and environmental degradation present major challenges. Solar energy offers a clean and viable renewable energy source with the potential to alleviate the detrimental consequences normally associated with fossil fuel-based energy generation. However, there are two inherent problems associated with conventional solar thermal energy conversion systems. The first involves low thermal conductivity values of heat transfer fluids, and the second involves the poor optical properties of many absorbers and their coating. Hence, there is an imperative need to improve both thermal and optical properties of current solar conversion systems. Direct solar thermal absorption collectors incorporating a nanofluid offers the opportunity to achieve significant improvements in both optical and thermal performance. Since nanofluids offer much greater heat absorbing and heat transfer properties compared to traditional working fluids. The review summarizes current research in this innovative field. It discusses direct solar absorber collectors and methods for improving their performance. This is followed by a discussion of the various types of nanofluids available and the synthesis techniques used to manufacture them. In closing, a brief discussion of nanofluid property modelling is also presented.

  11. A two dimensional thermal network model for a photovoltaic solar wall

    Energy Technology Data Exchange (ETDEWEB)

    Dehra, Himanshu [1-140 Avenue Windsor, Lachine, Quebec (Canada)

    2009-11-15

    A two dimensional thermal network model is proposed to predict the temperature distribution for a section of photovoltaic solar wall installed in an outdoor room laboratory in Concordia University, Montreal, Canada. The photovoltaic solar wall is constructed with a pair of glass coated photovoltaic modules and a polystyrene filled plywood board as back panel. The active solar ventilation through a photovoltaic solar wall is achieved with an exhaust fan fixed in the outdoor room laboratory. The steady state thermal network nodal equations are developed for conjugate heat exchange and heat transport for a section of a photovoltaic solar wall. The matrix solution procedure is adopted for formulation of conductance and heat source matrices for obtaining numerical solution of one dimensional heat conduction and heat transport equations by performing two dimensional thermal network analyses. The temperature distribution is predicted by the model with measurement data obtained from the section of a photovoltaic solar wall. The effect of conduction heat flow and multi-node radiation heat exchange between composite surfaces is useful for predicting a ventilation rate through a solar ventilation system. (author)

  12. Study on effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans

    Directory of Open Access Journals (Sweden)

    Sari Farah Dina

    2015-03-01

    Full Text Available The main objective is to assess effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans. Two type of desiccants were tested, molecular sieve 13× (Na86 [(AlO286·(SiO2106]·264H2O as an adsorbent type and CaCl2 as an absorbent type. The results revealed that during sunshine hours, the maximum temperature within the drying chamber varied from 40 °C to 54 °C. In average, it was 9–12 °C higher than ambient temperature. These temperatures are very suitable for drying cocoa beans. During off-sunshine hours, humidity of air inside the drying chamber was lower than ambient because of the desiccant thermal storage. Drying times for intermittent directs sun drying, solar dryer integrated with adsorbent, and solar dryer integrated with absorbent were 55 h, 41 h, and 30 h, respectively. Specific energy consumptions for direct sun drying, solar dryer integrated with adsorbent, and solar dryer integrated with absorber were 60.4 MJ/kg moist, 18.94 MJ/kg moist, and 13.29 MJ/kg moist, respectively. The main conclusion can be drawn here is that a solar dryer integrated with desiccant thermal storage makes drying using solar energy more effective in term of drying time and specific energy consumption.

  13. Thermally conductive and electrically insulating EVA composite encapsulant for solar photovoltaic (PV cell

    Directory of Open Access Journals (Sweden)

    2008-05-01

    Full Text Available A new way of improving the heat dissipating ability and PV efficiency of the solar cells by enhancing the thermal conductivity of the rear EVA layer was reported. The thermal conductivity, electrical resistivity, degree of curing of the EVA encapsulating composites and the PV efficiency of the solar cells are investigated. Filling with the thermal conductive fillers enhances the thermal conductivity of the composites effectively. The thermal conductivity of the filler influences significantly the thermal conductivity of the composite at high filler loading (greater than 20 vol%. Thermal conductivities of the composites filled with SiC, ZnO or BN reach respectively 2.85, 2.26 and 2.08 W/m•K at filler content of 60 vol%. The composites filled with ZnO or BN exhibit superior electrical insulation to those filled with SiC or Al2O3. ZnO can promote the cross-linking reaction of the EVA matrix. The test results indicated that the EVA composite encapsulating rear films filled with thermal conductive fillers are able to improve the PV efficiency and the heat dissipating ability of the solar cell effectively.

  14. Integrated photovoltaic-thermal solar energy conversion systems

    Science.gov (United States)

    Samara, G. A.

    1975-01-01

    A combined photovoltaic/thermal collector has been built and is now being tested. Initial tests have concentrated on evaluating the thermal efficiency of the collector before and after the silicon cells are mounted. With likely improvements in bonding between cells and receiver and in the absorptivity of the cells, thermal efficiencies greater than 50% can be expected for the combined receiver operating at 100 C.

  15. Thermal phase change actuator for self-tracking solar concentration

    National Research Council Canada - National Science Library

    Tremblay, E J; Loterie, D; Moser, C

    2012-01-01

    We present a proof of principle demonstration of a reversible in-plane actuator activated by focused sunlight, and describe a concept for its use as a self-tracking mechanism in a planar solar concentrator...

  16. The transient thermal response of a tubular solar collector

    Science.gov (United States)

    Lansing, F. L.

    1976-01-01

    A special analytical solution is provided for the timewise response of the circulating fluid temperatures when a sudden step change of the input solar radiation is imposed and remains constant thereafter. An example which demonstrates the transient temperatures at the exit section of a single collector with two different flow patterns is presented. This study is used to supplement some numerical solutions to provide a fairly complete coverage for this type of solar collector.

  17. Proceedings of the solar thermal concentrating collector technology symposium

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, B.P.; Kreith, F. (eds.)

    1978-08-01

    The purpose of the symposium was to review the current status of the concentrating collector technology, to disseminate the information gained from experience in operating solar systems, and to highlight the significant areas of technology development that must be vigorously pursued to foster early commercialization of concentrating solar collectors. Separate abstracts were prepared for thirteen invited papers and working group summaries. Two papers were previously abstracted for EDB.

  18. Whistler-cyclotron spontaneous fluctuations as a proxy to identify thermal and non-thermal electrons in the solar wind

    Science.gov (United States)

    Moya, P. S.; Vinas, A. F.; Navarro, R.; Araneda, J. A.

    2014-12-01

    Observed electron velocity distributions in the solar wind exhibit a variety of non-thermal features which deviate from thermal equilibrium, in the form of temperature anisotropies, suprathermal tails, and field aligned beams. The state close to thermal equilibrium and its departure from it provides a source for spontaneous emissions of electromagnetic fluctuations as for example the whistler cyclotron waves at electron scales. Here we present a comparative analysis of these fluctuations based upon anisotropic plasma modeled with thermal and non-thermal particle distributions. The analysis presented here considers the second-order theory of fluctuations and the dispersion relation of weakly transverse fluctuations, with wave vectors parallel to the uniform background magnetic field, in a finite temperature isotropic thermal bi-Maxwellian and non-thermal Tsallis-kappa-like magnetized electron-proton plasma. Dispersion analysis and stability thresholds are derived for these non-thermal distributions and compared with similar results obtained from PIC simulations using plasma and field parameters relevant to the solar wind environments. Our results indicate that there is a strong dependence between the shape of the velocity distribution function and the topological regions in the frequency-wave number plane in which the spontaneous fluctuations emerge. In the case of non-thermal plasmas there is an enhancement of the fluctuations level due to the effective higher-temperature effects and the excess of suprathermal particles. This feature may be used proxy to identify the nature of electron populations in space plasmas when high resolution particle instruments are not available.

  19. Design and optimization of nanoparticle-pigmented solar selective absorber coatings for high-temperature concentrating solar thermal systems

    Science.gov (United States)

    Wang, Xiaoxin; Yu, Xiaobai; Fu, Sidan; Lee, Eldred; Kekalo, Katerina; Liu, Jifeng

    2018-01-01

    We present a systematic approach for the design and optimization of nanoparticle-pigmented solar selective absorbers for operation at 750 °C. Using the scattering and absorption cross-sections calculated by Lorenz-Mie scattering theory as input, we employ a four-flux radiative transfer method to investigate the solar selectivity mechanism and optimize the optical-to-thermal conversion efficiency (ηtherm) as a function of the metallic nanoparticle material, the nanoparticle diameter, the volume fraction, and the coating thickness. Among the nanoparticle material candidates in this study, C54-TiSi2 is the best option with an optimized ηtherm = 87.0% for a solar concentration ratio of C = 100 and ηtherm = 94.4% for C = 1000 at 750 °C. NiSi is also a promising candidate comparable to TiSi2 in thermal efficiency. Experimentally, an un-optimized 200 nm-diameter TiSi2 nanoparticle-silicone solar selective coating has already achieved ηtherm = 89.8% for C = 1000 at 750 °C. This performance is consistent with the theoretical model and close to the thermal efficiency of the commercial Pyromark 2500 coatings (90.1%). We also demonstrate that Ni/NiSi core-shell structures embedded in the SiO1.5 matrix is thermally stable at 750 °C for 1000 h in air. These results indicate that silicide cermet coatings are promising to achieve high optical performance and high temperature thermal stability simultaneously.

  20. Assessing the techno-economics of modular hybrid solar thermal systems

    Science.gov (United States)

    Lim, Jin Han; Chinnici, Alfonso; Dally, Bassam; Nathan, Graham

    2017-06-01

    A techno-economic assessment was performed on modular hybrid solar thermal (in particular, solar power tower) systems with combustion from natural gas as backup to provide a continuous supply of electricity. Two different configurations were compared, i.e. a Hybrid Solar Receiver Combustor (HSRC), in which the functions of a solar cavity receiver and a combustor are integrated into a single device, and a Solar Gas Hybrid (SGH), which is a reference hybrid solar thermal system with a standalone solar-only cavity receiver and a backup boiler. The techno-economic benefits were assessed by varying the size of the modular components, i.e. the heliostat field and the solar receivers. It was found that for modularization to be cost effective requires more than the increased learning from higher production of a larger number of smaller units, such as access to alternative, lower-cost manufacturing methods and/or the use of a low melting point Heat Transfer Fluid (HTF) such as sodium to reduce parasitic losses. In particular, for a plant with 30 units of 1MWth modules, the Levelized Cost of Electricity is competitive compared with a single unit of 30MWth after ˜100 plants are installed for both the HSRC and SGH if the systems employ the use of sodium as the heat transfer fluid.

  1. SOLAR POWER PLANTS IN THE EU. AN ENVIRONMENTALLY-FRIENDLY ENGINE FOR THE EUROPEAN ECONOMIES

    Directory of Open Access Journals (Sweden)

    Mircea SAVEANU

    2014-10-01

    Full Text Available We establish that the European Union is facing severe ecological problems, by analysing the ecological footprint of selected member states. Many of these problems are related to carbon and carbon equivalent emissions, some of which are generated by fossil fuel power plants. It is then shown that the European Union has potential in the solar power renewable energy sector. Finally, we calculate roughly how much land would be necessary in order to replace fossil fuel power plants, as well as nuclear plants, which are largely seen as environmentally dangerous. It is concluded that developing this alternative energy sector would help improve the ecological sustainability of the Union, by diminishing a significant part of its carbon footprint.

  2. Flexible hybrid energy cell for simultaneously harvesting thermal, mechanical, and solar energies.

    Science.gov (United States)

    Yang, Ya; Zhang, Hulin; Zhu, Guang; Lee, Sangmin; Lin, Zong-Hong; Wang, Zhong Lin

    2013-01-22

    We report the first flexible hybrid energy cell that is capable of simultaneously or individually harvesting thermal, mechanical, and solar energies to power some electronic devices. For having both the pyroelectric and piezoelectric properties, a polarized poly(vinylidene fluoride) (PVDF) film-based nanogenerator (NG) was used to harvest thermal and mechanical energies. Using aligned ZnO nanowire arrays grown on the flexible polyester (PET) substrate, a ZnO-poly(3-hexylthiophene) (P3HT) heterojunction solar cell was designed for harvesting solar energy. By integrating the NGs and the solar cells, a hybrid energy cell was fabricated to simultaneously harvest three different types of energies. With the use of a Li-ion battery as the energy storage, the harvested energy can drive four red light-emitting diodes (LEDs).

  3. Modelling the Size of Seasonal Thermal Storage in the Solar District Heating System

    Directory of Open Access Journals (Sweden)

    Giedrė Streckienė

    2012-12-01

    Full Text Available The integration of a thermal storage system into the solar heating system enables to increase the use of solar thermal energy in buildings and allows avoiding the mismatch between consumers’ demand and heat production in time. The paper presents modelling a seasonal thermal storage tank various sizes of which have been analyzed in the district solar heating system that could cover a part of heat demand for the district of individual houses in Vilnius. A biomass boiler house, as an additional heat source, should allow covering the remaining heat demand. energyPRO software is used for system modelling. The paper evaluates heat demand, climate conditions and technical characteristics.Article in Lithuanian

  4. Military markets for solar thermal electric power systems

    Science.gov (United States)

    Hauger, J. S.

    1980-05-01

    The Department of Defense maintains an inventory of over 1,800 MW of engine-generators 15 KW and larger, with an estimated procurement rate of over 140 MW/year. Nearly the entire requirement could be met by advanced heat engines of the types being developed as point-focussing, distributed receiver power plants. A conceptual system consisting of a heat engine which efficiently burns liquid fossil or synthetic fuels, with a 'solarization kit' for conversion to hybrid solar operation could meet existing DOD requirements for new systems which are quieter, lighter, and multi-fueled. An estimated 24 percent (33 MW/year) or more could operationally benefit from the solar option. Baseline cost projections indicate levelized energy cost goals of 210 to 120 mills/KWh (15 to 1000 KW systems). Fuel cost escalation is the major factor affecting the value of the solar option. A baseline calculation for fuel at $0.59/gal in spring, 1979, escalating at 8 percent above general inflation indicates a value of $2700/KWe for a solarization kit.

  5. Characterization of Air-Based Photovoltaic Thermal Panels with Bifacial Solar Cells

    OpenAIRE

    P. Ooshaksaraei; Sopian, K.; R. Zulkifli; Saleem H. Zaidi

    2013-01-01

    Photovoltaic (PV) panels account for a majority of the cost of photovoltaic thermal (PVT) panels. Bifacial silicon solar panels are attractive for PVT panels because of their potential to enhance electrical power generation from the same silicon wafer compared with conventional monofacial solar panels. This paper examines the performance of air-based bifacial PVT panels with regard to the first and second laws of thermodynamics. Four air-based bifacial PVT panels were designed. The maximum ef...

  6. Comparative Ab-Initio Study of Substituted Norbornadiene-Quadricyclane Compounds for Solar Thermal Storage

    OpenAIRE

    Kuisma, Mikael J.; Lundin, Angelica M.; Moth-Poulsen, Kasper; Hyldgaard, Per; Erhart, Paul

    2016-01-01

    Molecular photoswitches that are capable of storing solar energy, so-called molecular solar thermal storage systems, are interesting candidates for future renewable energy applications. In this context, substituted norbornadiene-quadricyclane systems have received renewed interest due to recent advances in their synthesis. The optical, thermodynamic, and kinetic properties of these systems can vary dramatically depending on the chosen substituents. The molecular design of optimal compounds th...

  7. SOLCOST - Version 3. 0. Solar energy design program for non-thermal specialists

    Energy Technology Data Exchange (ETDEWEB)

    1980-05-01

    The SOLCOST solar energy design program is a public domain computerized design tool intended for use by non-thermal specialists to size solar systems with a methodology based on life cycle cost. An overview of SOLCOST capabilities and options is presented. A detailed guide to the SOLCOST input parameters is included. Sample problems showing typical imput decks and resulting SOLCOST output sheets are given. Details of different parts of the analysis are appended. (MHR)

  8. Analysis of Solar-Heated Thermal Wadis to Support Extended-Duration Lunar Exploration

    Science.gov (United States)

    Balasubramaniam, R.; Wegeng, R. S.; Gokoglu, S. A.; Suzuki, N. H.; Sacksteder, K. R.

    2010-01-01

    The realization of the renewed exploration of the Moon presents many technical challenges; among them is the survival of lunar surface assets during periods of darkness when the lunar environment is very cold. Thermal wadis are engineered sources of stored solar energy using modified lunar regolith as a thermal storage mass that can enable the operation of lightweight robotic rovers or other assets in cold, dark environments without incurring potential mass, cost, and risk penalties associated with various onboard sources of thermal energy. Thermal wadi-assisted lunar rovers can conduct a variety of long-duration missions including exploration site surveys; teleoperated, crew-directed, or autonomous scientific expeditions; and logistics support for crewed exploration. This paper describes a thermal analysis of thermal wadi performance based on the known solar illumination of the moon and estimates of producible thermal properties of modified lunar regolith. Analysis was performed for the lunar equatorial region and for a potential Outpost location near the lunar south pole. The results are presented in some detail in the paper and indicate that thermal wadis can provide the desired thermal energy reserve, with significant margin, for the survival of rovers or other equipment during periods of darkness.

  9. Experimental investigation of a nanofluid absorber employed in a low-profile, concentrated solar thermal collector

    Science.gov (United States)

    Li, Qiyuan; Zheng, Cheng; Mesgari, Sara; Hewakuruppu, Yasitha L.; Hjerrild, Natasha; Crisostomo, Felipe; Morrison, Karl; Woffenden, Albert; Rosengarten, Gary; Scott, Jason A.; Taylor, Robert A.

    2015-12-01

    Recent studies [1-3] have demonstrated that nanotechnology, in the form of nanoparticles suspended in water and organic liquids, can be employed to enhance solar collection via direct volumetric absorbers. However, current nanofluid solar collector experimental studies are either relevant to low-temperature flat plate solar collectors (100 °C) indoor laboratory-scale concentrating solar collectors [1, 5]. Moreover, many of these studies involve in thermal properties of nanofluid (such as thermal conductivity) enhancement in solar collectors by using conventional selective coated steel/copper tube receivers [6], and no full-scale concentrating collector has been tested at outdoor condition by employing nanofluid absorber [2, 6]. Thus, there is a need of experimental researches to evaluate the exact performance of full-scale concentrating solar collector by employing nanofluids absorber at outdoor condition. As reported previously [7-9], a low profile (solar thermal concentrating collector was designed and analysed which can potentially supply thermal energy in the 100-250 °C range (an application currently met by gas and electricity). The present study focuses on the design and experimental investigation of a nanofluid absorber employed in this newly designed collector. The nanofluid absorber consists of glass tubes used to contain chemically functionalized multi-walled carbon nanotubes (MWCNTs) dispersed in DI water. MWCNTs (average diameter of 6-13 nm and average length of 2.5-20 μm) were functionalized by potassium persulfate as an oxidant. The nanofluids were prepared with a MCWNT concentration of 50 +/- 0.1 mg/L to form a balance between solar absorption depth and viscosity (e.g. pumping power). Moreover, experimentally comparison of the thermal efficiency between two receivers (a black chrome-coated copper tube versus a MWCNT nanofluid contained within a glass tubetube) is investigated. Thermal experimentation reveals that while the collector efficiency

  10. Experimental Investigation on a Thermal Model for a Basin Solar Still with an External Reflector

    Directory of Open Access Journals (Sweden)

    Masoud Afrand

    2016-12-01

    Full Text Available In this study, a thermal model for estimating the efficiency of a basin solar still with an external reflector was introduced using the energy balance equations of different parts of the solar still. Then, in order to verify the precision and accuracy of this model, a basin solar still with an external reflector was constructed and some experiments were performed. The hourly temperature values for different places of the still and amount of distilled water were calculated using the thermal model and compared with experimental measurements. Comparisons show that the thermal model of the still is in good agreement with the experimental results. Therefore, it can be concluded that the introduced thermal model can be used reliably to estimate the amount of distilled water and efficiency of the basin solar still with an external reflector. Results also revealed that the efficiency of the solar still is low in the early hours, while it was enhanced 44% in the afternoon. Furthermore, it was concluded that the accumulated distilled water is 4600 mL/day and 4300 mL/day for theoretical and experimental examinations, respectively.

  11. Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels.

    Science.gov (United States)

    Kucharski, Timothy J; Ferralis, Nicola; Kolpak, Alexie M; Zheng, Jennie O; Nocera, Daniel G; Grossman, Jeffrey C

    2014-05-01

    Large-scale utilization of solar-energy resources will require considerable advances in energy-storage technologies to meet ever-increasing global energy demands. Other than liquid fuels, existing energy-storage materials do not provide the requisite combination of high energy density, high stability, easy handling, transportability and low cost. New hybrid solar thermal fuels, composed of photoswitchable molecules on rigid, low-mass nanostructures, transcend the physical limitations of molecular solar thermal fuels by introducing local sterically constrained environments in which interactions between chromophores can be tuned. We demonstrate this principle of a hybrid solar thermal fuel using azobenzene-functionalized carbon nanotubes. We show that, on composite bundling, the amount of energy stored per azobenzene more than doubles from 58 to 120 kJ mol(-1), and the material also maintains robust cyclability and stability. Our results demonstrate that solar thermal fuels composed of molecule-nanostructure hybrids can exhibit significantly enhanced energy-storage capabilities through the generation of template-enforced steric strain.

  12. Templated assembly of photoswitches significantly increases the energy-storage capacity of solar thermal fuels

    Science.gov (United States)

    Kucharski, Timothy J.; Ferralis, Nicola; Kolpak, Alexie M.; Zheng, Jennie O.; Nocera, Daniel G.; Grossman, Jeffrey C.

    2014-05-01

    Large-scale utilization of solar-energy resources will require considerable advances in energy-storage technologies to meet ever-increasing global energy demands. Other than liquid fuels, existing energy-storage materials do not provide the requisite combination of high energy density, high stability, easy handling, transportability and low cost. New hybrid solar thermal fuels, composed of photoswitchable molecules on rigid, low-mass nanostructures, transcend the physical limitations of molecular solar thermal fuels by introducing local sterically constrained environments in which interactions between chromophores can be tuned. We demonstrate this principle of a hybrid solar thermal fuel using azobenzene-functionalized carbon nanotubes. We show that, on composite bundling, the amount of energy stored per azobenzene more than doubles from 58 to 120 kJ mol-1, and the material also maintains robust cyclability and stability. Our results demonstrate that solar thermal fuels composed of molecule-nanostructure hybrids can exhibit significantly enhanced energy-storage capabilities through the generation of template-enforced steric strain.

  13. Thermal analysis of a Phase Change Material for a Solar Organic Rankine Cycle

    Science.gov (United States)

    Iasiello, M.; Braimakis, K.; Andreozzi, A.; Karellas, S.

    2017-11-01

    Organic Rankine Cycle (ORC) is a promising technology for low temperature power generation, for example for the utilization of medium temperature solar energy. Since heat generated from solar source is variable throughout the day, the implementation of Thermal Energy Storage (TES) systems to guarantee the continuous operation of solar ORCs is a critical task, and Phase Change Materials (PCM) rely on latent heat to store large amounts of energy. In the present study, a thermal analysis of a PCM for a solar ORC is carried out. Three different types of PCMs are analyzed. The energy equation for the PCM is modeled by using the heat capacity method, and it is solved by employing a 1Dexplicit finite difference scheme. The solar source is modeled with a time-variable temperature boundary condition, with experimental data taken from the literature for two different solar collectors. Results are presented in terms of temperature profiles and stored energy. It has been shown that the stored energy depends on the heat source temperature, on the employed PCM and on the boundary conditions. It has been demonstrated that the use of a metal foam can drastically enhance the stored energy due to the higher overall thermal conductivity.

  14. Thermal effects investigation on electrical properties of silicon solar cells treated by laser irradiation

    Directory of Open Access Journals (Sweden)

    Ali Pourakbar Saffar

    2014-12-01

    Full Text Available In this paper, we were investigated electrical properties of monocrystalline and polycrystalline silicon solar cells due to laser irradiation with 650 nm wavelength in two states, proximate irradiation and via optics setup. Thermal effect on the cell surface due to laser irradiation was investigated on electrical properties too. Electrical parameters investigation of solar cells illustrates cell excitement via laser irradiation and efficiency decreases due to cell surface temperature increase. Monocrystalline parameters change with uniform shape due to thermal effect and laser irradiation toward polycrystalline cells.

  15. The design of a vehicle-mounted test system for the thermal performance of solar collector

    Science.gov (United States)

    Wen, S. R.; Wu, X. H.; Zhou, L.; Zheng, W.; Liu, L.; Yan, J. C.

    2016-08-01

    To increase the test efficiency of thermal performance of solar collector, a vehicle- mounted test system with high automation, simple operation, good mobility and stability is proposed in this paper. By refitting a medium bus, design of mechanical system and test loop, and using PC control technology, we implemented the vehicle-mounted system and realized effective integration between vehicle and test equipment. A number of tests have been done, and the results show that the vehicle-mounted test system has good parameters and performance and can be widely used to provide door-to-door testing services in the field of solar thermal application.

  16. The effects of solar radiation and black body re-radiation on thermal comfort.

    Science.gov (United States)

    Hodder, Simon; Parsons, Ken

    2008-04-01

    When the sun shines on people in enclosed spaces, such as in buildings or vehicles, it directly affects thermal comfort. There is also an indirect effect as surrounding surfaces are heated exposing a person to re-radiation. This laboratory study investigated the effects of long wave re-radiation on thermal comfort, individually and when combined with direct solar radiation. Nine male participants (26.0 +/- 4.7 years) took part in three experimental sessions where they were exposed to radiation from a hot black panel heated to 100 degrees C; direct simulated solar radiation of 600 Wm(-2) and the combined simulated solar radiation and black panel radiation. Exposures were for 30 min, during which subjective responses and mean skin temperatures were recorded. The results showed that, at a surface temperature of 100 degrees C (close to maximum in practice), radiation from the flat black panel provided thermal discomfort but that this was relatively small when compared with the effects of direct solar radiation. It was concluded that re-radiation, from a dashboard in a vehicle, for example, will not have a major direct influence on thermal comfort and that existing models of thermal comfort do not require a specific modification. These results showed that, for the conditions investigated, the addition of re-radiation from internal components has an effect on thermal sensation when combined with direct solar radiation. However, it is not considered that it will be a major factor in a real world situation. This is because, in practice, dashboards are unlikely to maintain very high surface temperatures in vehicles without an unacceptably high air temperature. This study quantifies the contribution of short- and long-wave radiation to thermal comfort. The results will aid vehicle designers to have a better understanding of the complex radiation environment. These include direct radiation from the sun as well as re-radiation from the dashboard and other internal surfaces.

  17. Thermal phase diagram of acetamide-benzoic acid and benzoic acid-phthalimide binary systems for solar thermal applications

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rohitash, E-mail: dootrohit1976@gmail.com [Defence Laboratory Jodhpur, Rajasthan, India 342011, +91-2912567520 (India); Department of Physics & Center for Solar Energy, Indian Institute of Technology Jodhpur, Rajasthan, India 342011, +91-291-2449045 (India); Kumar, Ravindra [Defence Laboratory Jodhpur, Rajasthan, India 342011, +91-2912567520 (India); Dixit, Ambesh, E-mail: ambesh@iitj.ac.in [Department of Physics & Center for Solar Energy, Indian Institute of Technology Jodhpur, Rajasthan, India 342011, +91-291-2449045 (India)

    2016-05-06

    Thermal properties of Acetamide (AM) – Benzoic acid (BA) and Benzoic acid (BA) – Phthalimide (PM) binary eutectic systems are theoretically calculated using thermodynamic principles. We found that the binary systems of AM-BA at 67.6 : 32.4 molar ratio, BA-PM at 89.7 : 10.3 molar ratio form eutectic mixtures with melting temperatures ~ 54.5 °C and 114.3 °C respectively. Calculated latent heat of fusion for these eutectic mixtures are 191 kJ/kg and 146.5 kJ/kg respectively. These melting temperatures and heat of fusions of these eutectic mixtures make them suitable for thermal energy storage applications in solar water heating and solar cooking systems.

  18. By-Pass Diode Temperature Tests of a Solar Array Coupon under Space Thermal Environment Conditions

    Science.gov (United States)

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

    2016-01-01

    By-Pass diodes are a key design feature of solar arrays and system design must be robust against local heating, especially with implementation of larger solar cells. By-Pass diode testing was performed to aid thermal model development for use in future array designs that utilize larger cell sizes that result in higher string currents. Testing was performed on a 56-cell Advanced Triple Junction solar array coupon provided by SSL. Test conditions were vacuum with cold array backside using discrete by-pass diode current steps of 0.25 A ranging from 0 A to 2.0 A.

  19. Indoor test for thermal performance evaluation of seven Elcam fin-tube solar collector configurations

    Science.gov (United States)

    1979-01-01

    The test procedure used and the results obtained from an evaluation test program conducted to obtain thermal performance data on seven Elcam fin-tube solar collector configurations under simulated conditions are described. These tests were made using the Marshall Space Flight Center solar facilities. The Elcam fin-tube (liquid) solar collectors each consist of an absorber plate 5.9 inches wide by 83 inches long and a type M copper tube of 0.569 inch nominal inside diameter. No cover plate was used with any of the specimens. The uniqueness of each of the seven configurations is described, and tests were performed on each separate configuration.

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

    Science.gov (United States)

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

    1985-01-01

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

  1. Thermal performance evaluation of the Suncatcher SH-11 (liquid) solar collector

    Science.gov (United States)

    1980-01-01

    The procedures used and the results obtained during the evaluation test program on the Solar Unlimited, Inc., Suncatcher SH-11 (liquid) solar collector are presented. The flat-plate collector case assembly is made of .08 inch aluminum 3003 H14 riveted with fiberglass board insulation. The absorber consists of collared aluminum fins mechanically bonded to 3/8 inch copper tubing and coated with 3M Nextel black. Water is used as the working fluid. The glazing is made of a single glass, 1/8 inch water white, tempered and antireflective. The collector weight is 85 pounds with overall external dimensions of about 35.4 in x 82.0 in x 4.0 in. Thermal performance data on the Solar Unlimited Suncatcher SH-11 solar collector under simulated conditions were conducted using the MSFC Solar Simulator.

  2. Membrane Material-Based Rigid Solar Array Design and Thermal Simulation for Stratospheric Airships

    Directory of Open Access Journals (Sweden)

    Kangwen Sun

    2014-01-01

    Full Text Available In order to improve effective utilization of rigid solar array used in stratospheric airships here, the flexible connection design and light laminated design were introduced to rigid solar array. Based on the analysis of the design scheme, firstly, the equivalent coefficient of thermal conductivity was calculated by the theoretical formula. Subsequently, the temperature variation characteristics of the solar cell module were accurately modeled and simulated by using Computational Fluid Dynamics (CFD software. Compared to the results of test samples, the solar cell module described here guaranteed effective output as well as good heat insulating ability, effectively improving the feasibility of the stratospheric airship design. In addition, the simulation model can effectively simulate the temperature variation characteristics of the solar cell, which, therefore, provides technical support for the engineering application.

  3. Effects of Nonuniform Incident Illumination on the Thermal Performance of a Concentrating Triple Junction Solar Cell

    Directory of Open Access Journals (Sweden)

    Fahad Al-Amri

    2014-01-01

    Full Text Available A numerical heat transfer model was developed to investigate the temperature of a triple junction solar cell and the thermal characteristics of the airflow in a channel behind the solar cell assembly using nonuniform incident illumination. The effects of nonuniformity parameters, emissivity of the two channel walls, and Reynolds number were studied. The maximum solar cell temperature sharply increased in the presence of nonuniform light profiles, causing a drastic reduction in overall efficiency. This resulted in two possible solutions for solar cells to operate in optimum efficiency level: (i adding new receiver plate with higher surface area or (ii using forced cooling techniques to reduce the solar cell temperature. Thus, surface radiation exchanges inside the duct and Re significantly reduced the maximum solar cell temperature, but a conventional plain channel cooling system was inefficient for cooling the solar cell at medium concentrations when the system was subjected to a nonuniform light distribution. Nonuniformity of the incident light and surface radiation in the duct had negligible effects on the collected thermal energy.

  4. Economic load dispatch of wind-solar-thermal system using ...

    African Journals Online (AJOL)

    Due to rise in the price of fossil fuels and technical advances in the area of renewable energy, integrated systems became more popular now a day. However uncertain nature of wind, solar irradiation due to weather and climate change, integration of renewable power generation system complicates the ELD formulation.

  5. A thermal comparison among several beverage can solar collectors.

    Science.gov (United States)

    Peter Y.S. Chen

    1984-01-01

    Four air-heated solar collectors were built using four different configurations of aluminum beverage cans. The collectors were then tested for four consecutive seasons for their daily efficiencies. One of the collectors was also evaluated for one season for the effect of air velocity on efficiency, temperature rise, and power consumption of the collector.

  6. Evaluation of ORC processes and their implementation in solar thermal DSG plants

    OpenAIRE

    Degli Esposti, Dalma

    2014-01-01

    Abstract In recent years Direct Steam Generation (DSG) systems using water have been developed as an alternative to state-of-the-art parabolic trough plants with thermal oil. After a comprehensive research, first commercial DSG plants have already been realized. Organic Rankine Cycles (ORC) that have been widely used for electricity production with low-temperature heat (e.g. geothermal energy) are also suited for the implementation in solar thermal power plants. To the knowledge of t...

  7. Optimization of solar thermal dryer designs for the production of sun-dried apricots (Prunus armeniaca)(abstract)

    Science.gov (United States)

    Solar thermal (ST) drying is a ubiquitous method that has had widespread use for fruit and vegetable crop preservation in developing countries. Conversely, in the United States solar thermal drying has found limited commercialization due to concerns about slow drying rates and poor product quality. ...

  8. A Novel Modeling of Molten-Salt Heat Storage Systems in Thermal Solar Power Plants

    Directory of Open Access Journals (Sweden)

    Rogelio Peón Menéndez

    2014-10-01

    Full Text Available Many thermal solar power plants use thermal oil as heat transfer fluid, and molten salts as thermal energy storage. Oil absorbs energy from sun light, and transfers it to a water-steam cycle across heat exchangers, to be converted into electric energy by means of a turbogenerator, or to be stored in a thermal energy storage system so that it can be later transferred to the water-steam cycle. The complexity of these thermal solar plants is rather high, as they combine traditional engineering used in power stations (water-steam cycle or petrochemical (oil piping, with the new solar (parabolic trough collector and heat storage (molten salts technologies. With the engineering of these plants being relatively new, regulation of the thermal energy storage system is currently achieved in manual or semiautomatic ways, controlling its variables with proportional-integral-derivative (PID regulators. This makes the overall performance of these plants non optimal. This work focuses on energy storage systems based on molten salt, and defines a complete model of the process. By defining such a model, the ground for future research into optimal control methods will be established. The accuracy of the model will be determined by comparing the results it provides and those measured in the molten-salt heat storage system of an actual power plant.

  9. Galileo probe measurements of thermal and solar radiation fluxes in the Jovian atmosphere

    Science.gov (United States)

    Sromovsky, L. A.; Collard, A. D.; Fry, P. M.; Orton, G. S.; Lemmon, M. T.; Tomasko, M. G.; Freedman, R. S.

    1998-09-01

    The Galileo probe net flux radiometer (NFR) measured radiation fluxes in Jupiter's atmosphere from about 0.44 to 14 bars, using five spectral channels to separate solar and thermal components. Onboard calibration results confirm that the NFR responded to radiation approximately as expected. NFR channels also responded to a superimposed thermal perturbation, which can be approximately removed using blind channel measurements and physical constraints. Evidence for the expected NH3 cloud was seen in the spectral character of spin-induced modulations of the direct solar beam signals. These results are consistent with an overlying cloud of small NH3 ice particles (0.5-0.75 μm in radius) of optical depth 1.5-2 at 0.5 μm. Such a cloud would have so little effect on thermal fluxes that NFR thermal channels provide no additional constraints on its properties. However, evidence for heating near 0.45 bar in the NFR thermal channels would seem to require either an additional opacity source beyond this small-particle cloud, implying a heterogeneous cloud structure to avoid conflicts with solar modulation results, or a change in temperature lapse rate just above the probe measurements. The large thermal flux levels imply water vapor mixing ratios that are only 6% of solar at 10 bars, but possibly increasing with depth, and significantly subsaturated ammonia at pressures less than 3 bars. If deep NH3 mixing ratios at the probe entry site are 3-4 times ground-based inferences, as suggested by probe radio signal attenuation, then only half as much water is needed to match NFR observations. No evidence of a water cloud was seen near the 5-bar level. The 5-μm thermal channel detected the presumed NH4SH cloud base near 1.35 bars. Effects of this cloud were also seen in the solar channel upflux measurements but not in the solar net fluxes, implying that the cloud is a conservative scatterer of sunlight. The minor thermal signature of this cloud is compatible with particle radii near

  10. Theoretical and experimental evaluation of solar chimney with thermal inertia; Evaluacion energetica teorica y experimental de una chimenea solar con enercia termica

    Energy Technology Data Exchange (ETDEWEB)

    Marti Herrero, J.; Heras Celemin, M. R.

    2004-07-01

    A simple study has been realized about the solar chimney built at the LECE, using FLUENNT, a Computational Fluid Dynamics (CFD) software. The more important restrictions imposed to the simulation has bee: stationary state and no interaction between the solar chimney and the atmosphere. The results shows a discrepancy between the theory and experimental data, because the conditions employed on the simulation. The solar chimney has a concrete wall with thermal inertia, that is not represented on the simulation because the stationary state. It is necessary to research on more detailed dynamic studies using CDF, in order to obtain the energetic performance of a solar chimney with thermal inertia. (Author)

  11. NST: Thermal Modeling for a Large Aperture Solar Telescope

    Science.gov (United States)

    Coulter, Roy

    2011-05-01

    Late in the 1990s the Dutch Open Telescope demonstrated that internal seeing in open, large aperture solar telescopes can be controlled by flushing air across the primary mirror and other telescope structures exposed to sunlight. In that system natural wind provides a uniform air temperature throughout the imaging volume, while efficiently sweeping heated air away from the optics and mechanical structure. Big Bear Solar Observatory's New Solar Telescope (NST) was designed to realize that same performance in an enclosed system by using both natural wind through the dome and forced air circulation around the primary mirror to provide the uniform air temperatures required within the telescope volume. The NST is housed in a conventional, ventilated dome with a circular opening, in place of the standard dome slit, that allows sunlight to fall only on an aperture stop and the primary mirror. The primary mirror is housed deep inside a cylindrical cell with only minimal openings in the side at the level of the mirror. To date, the forced air and cooling systems designed for the NST primary mirror have not been implemented, yet the telescope regularly produces solar images indicative of the absence of mirror seeing. Computational Fluid Dynamics (CFD) analysis of the NST primary mirror system along with measurements of air flows within the dome, around the telescope structure, and internal to the mirror cell are used to explain the origin of this seemingly incongruent result. The CFD analysis is also extended to hypothetical systems of various scales. We will discuss the results of these investigations.

  12. Far-IR and Radio Thermal Continua in Solar Flares

    Czech Academy of Sciences Publication Activity Database

    Kašparová, Jana; Heinzel, Petr; Karlický, Marian; Moravec, Z.; Varady, M.

    2009-01-01

    Roč. 33, - (2009), s. 309-315 ISSN 1845-8319 R&D Projects: GA ČR GA205/04/0358; GA ČR GP205/06/P135; GA ČR GA205/07/1100 Institutional research plan: CEZ:AV0Z10030501 Keywords : solar flares * radiative hydrodynamics * continuum emission Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics

  13. Impact of European Territorial Cooperation (ETC on the promotion and use of solar energy in the Mediterranean

    Directory of Open Access Journals (Sweden)

    J. Gomez Prieto

    2016-01-01

    Full Text Available The aim of this paper is to assess the contribution of European Territorial Cooperation (ETC programmes operating in the Mediterranean area as a supporting way to achieve the renewable energy objectives established in European Union Directive 2009/28/EC. It addresses a combination of impact and thematic assessment applied to projects tackling solar energy over the period 2007–13. Observations indicate that although not always measurable, ETC contributions to the use and promotion of solar energy in the Mediterranean represent a key step forward in higher deployment. The paper also suggest alternatives to improve projects’ outputs to be delivered in the new cycle 2014–20.

  14. Energy dashboard for real-time evaluation of a heat pump assisted solar thermal system

    Science.gov (United States)

    Lotz, David Allen

    The emergence of net-zero energy buildings, buildings that generate at least as much energy as they consume, has lead to greater use of renewable energy sources such as solar thermal energy. One example is a heat pump assisted solar thermal system, which uses solar thermal collectors with an electrical heat pump backup to supply space heating and domestic hot water. The complexity of such a system can be somewhat problematic for monitoring and maintaining a high level of performance. Therefore, an energy dashboard was developed to provide comprehensive and user friendly performance metrics for a solar heat pump system. Once developed, the energy dashboard was tested over a two-week period in order to determine the functionality of the dashboard program as well as the performance of the heating system itself. The results showed the importance of a user friendly display and how each metric could be used to better maintain and evaluate an energy system. In particular, Energy Factor (EF), which is the ratio of output energy (collected energy) to input energy (consumed energy), was a key metric for summarizing the performance of the heating system. Furthermore, the average EF of the solar heat pump system was 2.29, indicating an efficiency significantly higher than traditional electrical heating systems.

  15. JPL - Small Power Systems Applications Project. [for solar thermal power plant development and commercialization

    Science.gov (United States)

    Ferber, R. R.; Marriott, A. T.; Truscello, V.

    1978-01-01

    The Small Power Systems Applications (SPSA) Project has been established to develop and commercialize small solar thermal power plants. The technologies of interest include all distributed and central receiver technologies which are potentially economically viable in power plant sizes of one to 10 MWe. The paper presents an overview of the SPSA Project and briefly discusses electric utility involvement in the Project.

  16. Spillage and flux density on a receiver aperture lip. [of solar thermal collector

    Science.gov (United States)

    Jaffe, L. D.

    1985-01-01

    In a dish-type point-focusing solar thermal collector, the spillage and the flux density on the receiver aperture lip are related in a very simple way, if the aperture is circular and centered on the optical axis. Specifically, the flux density on the lip is equal to the spillage times the peak flux density in the plane of the lip.

  17. Quasi-steady state thermal performances of a solar air heater with ...

    African Journals Online (AJOL)

    Quasi-steady state thermal performance of a solar air heater with a combined absorber is studied. The whole energy balance equations related to the system were articulated as a linear system of temperature equations. Solutions to this linear system were assessed from program based on an iterative process. The mean ...

  18. quasi-steady state thermal performances of a solar air heater with ...

    African Journals Online (AJOL)

    2017-01-17

    Jan 17, 2017 ... this linear system were assessed from program based on an iterative process. The mean temperature variation with time and the thermal performance parameters were .... 5 cm each, (6) an adiabatic envelope of protection made of wood. A fraction of the incident solar radiation G0 falling on the collector is ...

  19. Decentralised cooling of electronic equipment using the thermal conversion of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez, P.; Lecuona, A.; Venegas, M.; Sardina, M.; Rodriguez, M.C.; Lopez, S. [Departamento de Ingenieria Termica y de Fluidos, Universidad Carlos III de Madrid (UC3M), Madrid, (SP); Izquierdo, M. [Instituto de Ciencias de la Construccion Eduardo Torroja (CSIC), Madrid (SP)

    2002-07-01

    In this work, the application of solar energy in electronic equipment cooling is evaluated. The whole facility including thermal load, an absorption cooling machine, a gas driven boiler and a thermal solar system composed by 50 m2 of flat collectors, heat exchanger, 2 m3 storage tank and pumps, is simulated. Real environmental data corresponding to several extremely hot summer days in Madrid including solar radiation, ambient temperature and humidity and wind velocity and direction, were measured and applied in the system performance evaluation. For model validation, a 50 m2 flat thermal solar panels system in the UC3M, were monitored with temperature and water flow sensors. The absorption cooling machine was also monitored. Experimental data were taken at 2 seconds acquisition rate, saving averaged values over 10 minutes. Thermal environmental and electrical load daily fluctuation was also simulated using a communication wireless real equipment specifications. With the assistance of simulation, the effect of storage tank dimensioning on the system operating time is analyzed. Finally, a comparison with a conventional mechanical compressor driven cooling machine is performed. The environmental impact reduction is also computed and results are shown and discussed.

  20. An overview of CFD and PIV application in investigation of solar thermal systems

    DEFF Research Database (Denmark)

    Ai, Ning; Fan, Jianhua; Ji, Jianbing

    2007-01-01

    . The most promising solution to this challenge is the use of computational fluid dynamics (CFD) in combination with particle image velocimetry (PIV),which will be the future trend in the investigation of solar thermal systems. The aim of this work is to give an overview of the status of the CFD...

  1. Thermal performance analysis and measurements of the prototype cryomodules of European XFEL accelerator-Part II

    Science.gov (United States)

    Wang, X. L.; Barbanotti, S.; Eschke, J.; Jensch, K.; Klos, R.; Maschmann, W.; Petersen, B.; Sawlanski, O.

    2014-11-01

    Three accelerator prototype cryomodules (CMs) for the European XFEL have been produced, assembled and tested at DESY in a wide international collaboration. The heat load budget is a key element in the qualification of these CMs. We describe in this paper the measurements performed in the Cryomodule test bench (CMTB) to evaluate the thermal performances of the three prototype CMs. We present at first the methodology and instrumentation used for the measurements, then we analyse the main contributions to the heat loads at various temperature levels and finally we compare the measured values with the ones calculated and reported in the first part of this paper.

  2. Low Molecular Weight Norbornadiene Derivatives for Molecular Solar-Thermal Energy Storage.

    Science.gov (United States)

    Quant, Maria; Lennartson, Anders; Dreos, Ambra; Kuisma, Mikael; Erhart, Paul; Börjesson, Karl; Moth-Poulsen, Kasper

    2016-09-05

    Molecular solar-thermal energy storage systems are based on molecular switches that reversibly convert solar energy into chemical energy. Herein, we report the synthesis, characterization, and computational evaluation of a series of low molecular weight (193-260 g mol(-1) ) norbornadiene-quadricyclane systems. The molecules feature cyano acceptor and ethynyl-substituted aromatic donor groups, leading to a good match with solar irradiation, quantitative photo-thermal conversion between the norbornadiene and quadricyclane, as well as high energy storage densities (396-629 kJ kg(-1) ). The spectroscopic properties and energy storage capability have been further evaluated through density functional theory calculations, which indicate that the ethynyl moiety plays a critical role in obtaining the high oscillator strengths seen for these molecules. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  3. Dispersed solar thermal generation employing parabolic dish-electric transport with field modulated generator systems

    Science.gov (United States)

    Ramakumar, R.; Bahrami, K.

    1981-01-01

    This paper discusses the application of field modulated generator systems (FMGS) to dispersed solar-thermal-electric generation from a parabolic dish field with electric transport. Each solar generation unit is rated at 15 kWe and the power generated by an array of such units is electrically collected for insertion into an existing utility grid. Such an approach appears to be most suitable when the heat engine rotational speeds are high (greater than 6000 r/min) and, in particular, if they are operated in the variable speed mode and if utility-grade a.c. is required for direct insertion into the grid without an intermediate electric energy storage and reconversion system. Predictions of overall efficiencies based on conservative efficiency figures for the FMGS are in the range of 25 per cent and should be encouraging to those involved in the development of cost-effective dispersed solar thermal power systems.

  4. Compendium of information on identification and testing of materials for plastic solar thermal collectors

    Energy Technology Data Exchange (ETDEWEB)

    McGinniss, V.D.; Sliemers, F.A.; Landstrom, D.K.; Talbert, S.G.

    1980-07-31

    This report is intended to organize and summarize prior and current literature concerning the weathering, aging, durability, degradation, and testing methodologies as applied to materials for plastic solar thermal collectors. Topics covered include (1) rate of aging of polymeric materials; (2) environmental factors affecting performance; (3) evaluation and prediction of service life; (4) measurement of physical and chemical properties; (5) discussion of evaluation techniques and specific instrumentation; (6) degradation reactions and mechanisms; (7) weathering of specific polymeric materials; and (8) exposure testing methodology. Major emphasis has been placed on defining the current state of the art in plastics degradation and on identifying information that can be utilized in applying appropriate and effective aging tests for use in projecting service life of plastic solar thermal collectors. This information will also be of value where polymeric components are utilized in the construction of conventional solar collectors or any application where plastic degradation and weathering are prime factors in material selection.

  5. High-temperature selective solar thermal absorber based on Fabry-Perot resonance cavity

    Science.gov (United States)

    Wang, Hao; Wang, Liping

    2015-09-01

    In this work, we investigate the design, fabrication and characterization of a multilayer selective solar absorber made of metallic and dielectric thin films. The investigated selective absorber exhibits theoretical spectral absorptance higher than 95% within solar spectrum and infrared emittance lower than 5%, due to the Fabry-Perot resonance and antireflection effect. In terms of fabrication, different materials are tested under high temperatures in order to obtain the structure with best thermal stability. Structures with different materials are fabricated with sputtering, chemical vapor deposition and electron beam evaporation techniques. The near normal reflectance is characterized with a Fourier Transform Infrared spectrometer for these structures before and after heat treatment. Meanwhile, Rutherford backscattering Spectroscopy is employed to analyze the diffusion and oxidation conditions during the heating process. Moreover, better material choice and fabrication techniques are considered to construct solar absorber sample with better high temperature thermal stability.

  6. Economic Dispatch for Power System Included Wind and Solar Thermal Energy

    Directory of Open Access Journals (Sweden)

    Saoussen BRINI

    2009-07-01

    Full Text Available With the fast development of technologies of alternative energy, the electric power network can be composed of several renewable energy resources. The energy resources have various characteristics in terms of operational costs and reliability. In this study, the problem is the Economic Environmental Dispatching (EED of hybrid power system including wind and solar thermal energies. Renewable energy resources depend on the data of the climate such as the wind speed for wind energy, solar radiation and the temperature for solar thermal energy. In this article it proposes a methodology to solve this problem. The resolution takes account of the fuel costs and reducing of the emissions of the polluting gases. The resolution is done by the Strength Pareto Evolutionary Algorithm (SPEA method and the simulations have been made on an IEEE network test (30 nodes, 8 machines and 41 lines.

  7. Toward Molecular Solar-Thermal Energy Storage: Systematic Search for New Molecular Systems

    Science.gov (United States)

    Durgun, Engin; Srinivasan, Varadharajan; Kanai, Yosuke; Wintrop, Gordon; Grossman, Jeffrey C.

    2010-03-01

    In the currently intensifying quest to harness solar energy for the powering of our planet, many efforts are centered around photo-induced generic charge separation, such as in photovoltaics, water splitting, and biologically inspired photosynthetic systems. An attractive alternative strategy would be to trap solar energy in the form of chemical bonds, ideally through the photo-conversion of a suitable molecule to a higher energy isomer, which, in turn, releases the stored energy by thermal reversal. Inspired by the discovery and investigations of fulvane-diruthenium, we explore strategies to discover new organometallic complexes that possess superior properties than organic molecules. We systematically search for complexes which are robust to storage cycles, easy to synthesize, tunable and which have high storage capacity and low UV excitation energies. Our analysis reveals that good organometallic candidates for solar-thermal energy storage systems can be identified and their performance can be improved through chemical substitution.

  8. Potential Use of a Salt Gradient Solar Pond to Store Thermal Energy

    Directory of Open Access Journals (Sweden)

    Daniel Vinícius Silva Veras

    2012-11-01

    Full Text Available Demand for energy sources that allow a sustainable development has stimulated studies on the acquisition of alternative energy, renewable and clean such as hydro, wind, biomass and solar energies. Therefore, the objective in this work was to evaluate the potential of a Salt Gradient Solar Pond (SGSP in order to obtain thermal energy from solar energy. A pilot solar pond with 1,76 m² of surface area and 1 m³ of volume was set up in Itapetinga, Bahia, and temperatures in upper and lower convective layers were monitored between August 20 and November 3, 2008. It was found that the temperature difference between the layers increased from 2°C to 13.2°C, with a medium value of 5.7°C for the period. Considering a 30% efficiency for utilization of stored energy, it would be possible increase by 10°C the temperature of 50 L of chilled milk in a dairy industry, thus demonstrating its potential. In the end of Spring or Summer the temperature difference would be superior. Results demonstrate the potential use of solar ponds by industries and farms in our country, as a renewable and non-polluting alternative, being able to store thermal energy from solar energy.

  9. SOLAR ENERGY POLICY DEVELOPMENTS IN EUROPE

    OpenAIRE

    Mihaela PÃCE?ILÃ

    2015-01-01

    Solar energy is one of the most important renewable energy sources in Europe offering new possibilities to generate electricity and heat. In this context, the study provides accurate information about researches that characterize the solar resource and investigates the potential of solar energy in European countries. The analysis is also focused on the current status of market development including photovoltaic capacity, electricity production from solar photovoltaic power, solar thermal capa...

  10. Thermal storage/discharge performances of Cu-Si alloy for solar thermochemical process

    Science.gov (United States)

    Gokon, Nobuyuki; Yamaguchi, Tomoya; Cho, Hyun-seok; Bellan, Selvan; Hatamachi, Tsuyoshi; Kodama, Tatsuya

    2017-06-01

    The present authors (Niigata University, Japan) have developed a tubular reactor system using novel "double-walled" reactor/receiver tubes with carbonate molten-salt thermal storage as a phase change material (PCM) for solar reforming of natural gas and with Al-Si alloy thermal storage as a PCM for solar air receiver to produce high-temperature air. For both of the cases, the high heat capacity and large latent heat (heat of solidification) of the PCM phase circumvents the rapid temperature change of the reactor/receiver tubes at high temperatures under variable and uncontinuous characteristics of solar radiation. In this study, we examined cyclic properties of thermal storage/discharge for Cu-Si alloy in air stream in order to evaluate a potentiality of Cu-Si alloy as a PCM thermal storage material. Temperature-increasing performances of Cu-Si alloy are measured during thermal storage (or heat-charge) mode and during cooling (or heat-discharge) mode. A oxidation state of the Cu-Si alloy after the cyclic reaction was evaluated by using electron probe micro analyzer (EPMA).

  11. Molten Salt-Carbon Nanotube Thermal Energy Storage for Concentrating Solar Power Systems Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Michael Schuller; Frank Little; Darren Malik; Matt Betts; Qian Shao; Jun Luo; Wan Zhong; Sandhya Shankar; Ashwin Padmanaban

    2012-03-30

    We demonstrated that adding nanoparticles to a molten salt would increase its utility as a thermal energy storage medium for a concentrating solar power system. Specifically, we demonstrated that we could increase the specific heat of nitrate and carbonate salts containing 1% or less of alumina nanoparticles. We fabricated the composite materials using both evaporative and air drying methods. We tested several thermophysical properties of the composite materials, including the specific heat, thermal conductivity, latent heat, and melting point. We also assessed the stability of the composite material with repeated thermal cycling and the effects of adding the nanoparticles on the corrosion of stainless steel by the composite salt. Our results indicate that stable, repeatable 25-50% improvements in specific heat are possible for these materials. We found that using these composite salts as the thermal energy storage material for a concentrating solar thermal power system can reduce the levelized cost of electricity by 10-20%. We conclude that these materials are worth further development and inclusion in future concentrating solar power systems.

  12. Fuzzy Approximate Model for Distributed Thermal Solar Collectors Control

    KAUST Repository

    Elmetennani, Shahrazed

    2014-07-01

    This paper deals with the problem of controlling concentrated solar collectors where the objective consists of making the outlet temperature of the collector tracking a desired reference. The performance of the novel approximate model based on fuzzy theory, which has been introduced by the authors in [1], is evaluated comparing to other methods in the literature. The proposed approximation is a low order state representation derived from the physical distributed model. It reproduces the temperature transfer dynamics through the collectors accurately and allows the simplification of the control design. Simulation results show interesting performance of the proposed controller.

  13. Photovoltaic and thermal energy conversion for solar powered satellites

    Science.gov (United States)

    Von Tiesenhausen, G. F.

    1976-01-01

    A summary is provided concerning the most important aspects of present investigations related to a use of solar power satellites (SPS) as a future source of terrestrial energy. General SPS characteristics are briefly considered, early work is reviewed, and a description of current investigations is presented. System options presently under study include a photovoltaic array, a thermionic system, and a closed Brayton cycle. Attention is given to system reference options, basic building blocks, questions of system analysis and engineering, photovoltaic conversion, and the utility interface. It is concluded that an SPS may be cost effective compared to terrestrial systems by 1995.

  14. A Novel Approach to Thermal Design of Solar Modules: Selective-Spectral and Radiative Cooling

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Xingshu; Dubey, Rajiv; Chattopadhyay, Shashwata; Khan, Mohammad Ryyan; Chavali, Raghu Vamsi; Silverman, Timothy J.; Kottantharayil, Anil; Vasi, Juzer; Alam, Muhammad Ashraful

    2016-11-21

    For commercial solar modules, up to 80% of the incoming sunlight may be dissipated as heat, potentially raising the temperature 20-30 degrees C higher than the ambient. In the long run, extreme self-heating may erode efficiency and shorten lifetime, thereby, dramatically reducing the total energy output by almost ~10% Therefore, it is critically important to develop effective and practical cooling methods to combat PV self-heating. In this paper, we explore two fundamental sources of PV self-heating, namely, sub-bandgap absorption and imperfect thermal radiation. The analysis suggests that we redesign the optical and thermal properties of the solar module to eliminate the parasitic absorption (selective-spectral cooling) and enhance the thermal emission to the cold cosmos (radiative cooling). The proposed technique should cool the module by ~10 degrees C, to be reflected in significant long-term energy gain (~ 3% to 8% over 25 years) for PV systems under different climatic conditions.

  15. Operation of metal hydride hydrogen storage systems for hydrogen compression using solar thermal energy

    Directory of Open Access Journals (Sweden)

    Naruki Endo

    2016-01-01

    Full Text Available By using a newly constructed bench-scale hydrogen energy system with renewable energy, ‘Pure Hydrogen Energy System’, the present study demonstrates the operations of a metal hydride (MH tank for hydrogen compression as implemented through the use solar thermal energy. Solar thermal energy is used to generate hot water as a heat source of the MH tank. Thus, 70 kg of LaNi5, one of the most typical alloys used for hydrogen storage, was placed in the MH tank. We present low and high hydrogen flow rate operations. Then, the operations under winter conditions are discussed along with numerical simulations conducted from the thermal point of view. Results show that a large amount of heat (>100 MJ is generated and the MH hydrogen compression is available.

  16. A Proposal to Develop and Test a Fibre-Optic Coupled Solar Thermal Propulsion System for Microsatellites

    Science.gov (United States)

    2006-03-01

    b) Figure 2.2: (a) Parabolic solar cooker . (b) Fresnel solar cooker Fibre Optic Solar Thermal Propulsion Demonstration Technology 8 external...based on the Virtual Polar Geostationary Satellite (VPGS) a concept studied at the NASA Jet Propulsion Laboratory [36] (figure (3.1b)). The concept...Polar Geostationary Satellite (VPGS),” Final Technical Report, Jet Propulsion Laboratory, 2000. [37] Henshall, P.R., Palmer, P., Baker, A., “Solar

  17. Radiative cooling of solar absorbers using a visibly transparent photonic crystal thermal blackbody

    Science.gov (United States)

    Zhu, Linxiao; Raman, Aaswath P.; Fan, Shanhui

    2015-01-01

    A solar absorber, under the sun, is heated up by sunlight. In many applications, including solar cells and outdoor structures, the absorption of sunlight is intrinsic for either operational or aesthetic considerations, but the resulting heating is undesirable. Because a solar absorber by necessity faces the sky, it also naturally has radiative access to the coldness of the universe. Therefore, in these applications it would be very attractive to directly use the sky as a heat sink while preserving solar absorption properties. Here we experimentally demonstrate a visibly transparent thermal blackbody, based on a silica photonic crystal. When placed on a silicon absorber under sunlight, such a blackbody preserves or even slightly enhances sunlight absorption, but reduces the temperature of the underlying silicon absorber by as much as 13 °C due to radiative cooling. Our work shows that the concept of radiative cooling can be used in combination with the utilization of sunlight, enabling new technological capabilities. PMID:26392542

  18. Radiative cooling of solar absorbers using a visibly transparent photonic crystal thermal blackbody.

    Science.gov (United States)

    Zhu, Linxiao; Raman, Aaswath P; Fan, Shanhui

    2015-10-06

    A solar absorber, under the sun, is heated up by sunlight. In many applications, including solar cells and outdoor structures, the absorption of sunlight is intrinsic for either operational or aesthetic considerations, but the resulting heating is undesirable. Because a solar absorber by necessity faces the sky, it also naturally has radiative access to the coldness of the universe. Therefore, in these applications it would be very attractive to directly use the sky as a heat sink while preserving solar absorption properties. Here we experimentally demonstrate a visibly transparent thermal blackbody, based on a silica photonic crystal. When placed on a silicon absorber under sunlight, such a blackbody preserves or even slightly enhances sunlight absorption, but reduces the temperature of the underlying silicon absorber by as much as 13 °C due to radiative cooling. Our work shows that the concept of radiative cooling can be used in combination with the utilization of sunlight, enabling new technological capabilities.

  19. Numerical analysis of using hybrid photovoltaic-thermal solar water heater in Iran

    Directory of Open Access Journals (Sweden)

    M Mohammadi Sarduei

    2017-05-01

    Full Text Available Introduction Electrical performance of solar cells decreases with increasing cell temperature, basically because of growth of the internal charge carrier recombination rates, caused by increased carrier concentrations. Hybrid Photovoltaic/thermal (PVT systems produce electrical and thermal energy simultaneously. PVT solar collectors convert the heat generated in the solar cells to low temperature useful heat energy and so they provide a lower working temperature for solar cells which subsequently leads to a higher electrical efficiency. Recently, in Iran, the reforming government policy in subsidy and increasing fossil fuels price led to growing an interest in use of renewable energies for residual and industrial applications. In spite of this, the PV power generator investment is not economically feasible, so far. Hybrid PVT devices are well known as an alternative method to improve energy performance and therefore economic feasibility of the conventional PV systems. The aim of this study is to investigate the performance of a PVT solar water heater in four different cities of Iran using TRNSYS program. Materials and Methods The designed PVT solar water system consists of two separate water flow circuits namely closed cycle and open circuit. The closed cycle circuit was comprised of a solar PVT collector (with nominal power of 880 W and area of 5.6 m2, a heat exchanger in the tank (with volume of 300 L, a pump and connecting pipes. The water stream in the collector absorbs the heat accumulated in the solar cells and delivers it to the water in the tank though the heat exchanger. An on/off controller system was used to activate the pump when the collector outlet temperature was higher than that of the tank in the closed cycle circuit. The water in the open circuit, comes from city water at low temperature, enters in the lower part of the storage tank where the heat transfer occurs between the two separate circuits. An auxiliary heater, connected

  20. Modeling and performance simulation of 100 MW PTC based solar thermal power plant in Udaipur India

    Directory of Open Access Journals (Sweden)

    Deepak Bishoyi

    2017-09-01

    Full Text Available Solar energy is a key renewable energy source and the most abundant energy source on the globe. Solar energy can be converted into electric energy by using two different processes: by means of photovoltaic (PV conversion and the thermodynamic cycles. Concentrated solar power (CSP is viewed as one of the most promising alternatives in the field of solar energy utilization. Lifetime and efficiency of PV system are very less compared to the CSP technology. A 100 MW parabolic trough solar thermal power plant with 6 h of thermal energy storage has been evaluated in terms of design and thermal performance, based on the System Advisor Model (SAM. A location receiving an annual DNI of 2248.17 kW h/m2 in Rajasthan is chosen for the technical feasibility of hypothetical CSP plant. The plant design consists of 194 solar collector loops with each loop comprising of 8 parabolic trough collectors. HITEC solar salt is chosen as an HTF due to its excellent thermodynamic properties. The designed plant can generate annual electricity of 285,288,352 kW h with the plant efficiency of 21%. The proposed design of PTC based solar thermal power plant and its performance analysis encourages further innovation and development of solar thermal power plants in India.

  1. Effects of Absorber Emissivity on Thermal Performance of a Solar Cavity Receiver

    Directory of Open Access Journals (Sweden)

    Jiabin Fang

    2014-01-01

    Full Text Available Solar cavity receiver is a key component to realize the light-heat conversion in tower-type solar power system. It usually has an aperture for concentrated sunlight coming in, and the heat loss is unavoidable because of this aperture. Generally, in order to improve the thermal efficiency, a layer of coating having high absorptivity for sunlight would be covered on the surface of the absorber tubes inside the cavity receiver. As a result, it is necessary to investigate the effects of the emissivity of absorber tubes on the thermal performance of the receiver. In the present work, the thermal performances of the receiver with different absorber emissivity were numerically simulated. The results showed that the thermal efficiency increases and the total heat loss decreases with increasing emissivity of absorber tubes. However, the thermal efficiency increases by only 1.6% when the emissivity of tubes varies from 0.2 to 0.8. Therefore, the change of absorber emissivity has slight effect on the thermal performance of the receiver. The reason for variation tendency of performance curves was also carefully analyzed. It was found that the temperature reduction of the cavity walls causes the decrease of the radiative heat loss and the convective heat loss.

  2. Evaluation and Error Analysis for a Solar thermal Receiver

    Energy Technology Data Exchange (ETDEWEB)

    Pfander, M.

    2001-07-01

    In the following study a complete balance over the REFOS receiver module, mounted on the tower power plant CESA-1 at the Plataforma Solar de Almeria (PSA), is carried out. Additionally an error inspection of the various measurement techniques used in the REFOS project is made. Especially the flux measurement system Prohermes that is used to determine the total entry power of the receiver module and known as a major error source is analysed in detail. Simulations and experiments on the particular instruments are used to determine and quantify possible error sources. After discovering the origin of the errors they are reduced and included in the error calculation. the ultimate result is presented as an overall efficiency of the receiver module in dependence on the flux density at the receiver module's entry plane and the receiver operating temperature. (Author) 26 refs.

  3. Multiscale Investigation of Thermal Fluctuations on Solar-Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Cheung, Margaret Shun [Univ. of Houston, TX (United States)

    2014-09-01

    Photoinduced charge transfer (CT) plays a central role in biologically significant systems and in applications that harvest solar energy. We investigate the relationship of CT kinetics and conformation in a molecular triad. The triad, consisting of carotenoid, porphyrin, and fullerene is structurally flexible and able to acquire significantly varied conformations under ambient conditions. With an integrated approach of quantum calculations and molecular dynamics simulations, we compute the rate of CT at two distinctive conformations. The linearly extended conformation, in which the donor (carotenoid) and the acceptor (fullerene) are separated by nearly 50 Å, enables charge separation through a sequential CT process. A representative bent conformation that is entropically dominant, however, attenuates the CT, although the donor and the acceptor are spatially closer. Our computed rate of CT at the linear conformation is in good agreement with measured values. Our work provides unique fundamental understanding of the photoinduced CT process in the molecular triad.

  4. Thermal Energy Storage using PCM for Solar Domestic Hot Water Systems: A Review

    Science.gov (United States)

    Khot, S. A.; Sane, N. K.; Gawali, B. S.

    2012-06-01

    Thermal energy storage using phase chase materials (PCM) has received considerable attention in the past two decades for time dependent energy source such as solar energy. From several experimental and theoretical analyses that have been made to assess the performance of thermal energy storage systems, it has been demonstrated that PCM-based systems are reliable and viable options. This paper covers such information on PCMs and PCM-based systems developed for the application of solar domestic hot water system. In addition, economic analysis of thermal storage system using PCM in comparison with conventional storage system helps to validate its commercial possibility. From the economic analysis, it is found that, PCM based solar domestic hot water system (SWHS) provides 23 % more cumulative and life cycle savings than conventional SWHS and will continue to perform efficiently even after 15 years due to application of non-metallic tank. Payback period of PCM-based system is also less compared to conventional system. In conclusion, PCM based solar water heating systems can meet the requirements of Indian climatic situation in a cost effective and reliable manner.

  5. Thermal design, analysis and comparison on three concepts of space solar power satellite

    Science.gov (United States)

    Yang, Chen; Hou, Xinbin; Wang, Li

    2017-08-01

    Space solar power satellites (SSPS) have been widely studied as systems for collecting solar energy in space and transmitting it wirelessly to earth. A previously designed planar SSPS concept collects solar power in two huge arrays and then transmits it through one side of the power-conduction joint to the antenna. However, the system's one group of power-conduction joints may induce a single point of failure. As an SSPS concept, the module symmetrical concentrator (MSC) architecture has many advantages. This architecture can help avoid the need for a large, potentially failure-prone conductive rotating joint and limit wiring mass. However, the thermal control system has severely restricted the rapid development of MSC, especially in the sandwich module. Because of the synchronous existence of five suns concentration and solar external heat flux, the sandwich module will have a very high temperature, which will surpass the permissible temperature of the solar cells. Recently, an alternate multi-rotary joints (MR) SSPS concept was designed by the China Academy of Space Technology (CAST). This system has multiple joints to avoid the problem of a single point of failure. Meanwhile, this concept has another advantage for reducing the high power and heat removal in joints. It is well known to us that, because of the huge external flux in SSPS, the thermal management sub-system is an important component that cannot be neglected. Based on the three SSPS concepts, this study investigated the thermal design and analysis of a 1-km, gigawatt-level transmitting antenna in SSPS. This study compares the thermal management sub-systems of power-conduction joints in planar and MR SSPS. Moreover, the study considers three classic thermal control architectures of the MSC's sandwich module: tile, step, and separation. The study also presents an elaborate parameter design, analysis and discussion of step architecture. Finally, the results show the thermal characteristics of each SSPS

  6. Effect of Selective Contacts on the Thermal Stability of Perovskite Solar Cells.

    Science.gov (United States)

    Zhao, Xing; Kim, Hui-Seon; Seo, Ja-Young; Park, Nam-Gyu

    2017-03-01

    Thermal stability of CH3NH3PbI3 (MAPbI3)-based perovskite solar cells was investigated for normal structure including the mesoporous TiO2 layer and spiro-MeOTAD and the inverted structure with PCBM and NiO. MAPbI3 was found to be intrinsically stable from 85 °C to 120 °C in the absence of moisture. However, fast degradation was observed for the encapsulated device including spiro-MeOTAD upon thermal stress at 85 °C. Photoluminescence (PL) intensity and the time constant for charge separation increased with thermal exposure time, which is indicative of inhibition of charge separation from MAPbI3 into spiro-MeOTAD. A full recovery of photovoltaic performance was observed for the 85 °C-aged device after renewal with fresh spiro-MeOTAD, which clearly indicates that thermal instability of the normal structured device is mainly due to spiro-MeOTAD, and MAPbI3 is proved to be thermally stable. Spiro-MeOTAD with additives was crystallized at 85 °C due to a low glass transition temperature, and hole mobility was significantly deteriorated, which was responsible for the thermal instability. Thermal stability was significantly improved for the inverted structure with the NiO hole transporting layer, where the power conversion efficiency (PCE) was maintained at 74% of its initial PCE of 14.71% after the 80th thermal cycle (one cycle: heating at 85 °C for 2 h and cooling at 25 °C for 2 h). This work implies that the thermal stability of perovskite solar cells depends on selective contacts.

  7. Solar cooling - comparative study between thermal and electrical use in industrial buildings

    Science.gov (United States)

    Badea, N.; Badea, G. V.; Epureanu, A.; Frumuşanu, G.

    2016-08-01

    The increase in the share of renewable energy sources together with the emphasis on the need for energy security bring to a spotlight the field of trigeneration autonomous microsystems, as a solution to cover the energy consumptions, not only for isolated industrial buildings, but also for industrial buildings located in urban areas. The use of solar energy for cooling has been taken into account to offer a cooling comfort in the building. Cooling and air- conditioned production are current applications promoting the use of solar energy technologies. Solar cooling systems can be classified, depending on the used energy, in electrical systems using mechanical compression chillers and systems using thermal compression by absorption or adsorption. This comparative study presents the main strengths and weaknesses of solar cooling obtained: i) through the transformation of heat resulted from thermal solar panels combined with adsorption chillers, and ii) through the multiple conversion of electricity - photovoltaic panels - battery - inverter - combined with mechanical compression chillers. Both solutions are analyzed from the standpoints of energy efficiency, dynamic performances (demand response), and costs sizes. At the end of the paper, experimental results obtained in the climatic condition of Galafi city, Romania, are presented.

  8. Theoretical analysis to investigate thermal performance of co-axial heat pipe solar collector

    Science.gov (United States)

    Azad, E.

    2011-12-01

    The thermal performance of co-axial heat pipe solar collector which consist of a collector 15 co-axial heat pipes surrounded by a transparent envelope and which heat a fluid flowing through the condenser tubes have been predicted using heat transfer analytical methods. The analysis considers conductive and convective losses and energy transferred to a fluid flowing through the collector condenser tubes. The thermal performances of co-axial heat pipe solar collector is developed and are used to determine the collector efficiency, which is defined as the ratio of heat taken from the water flowing in the condenser tube and the solar radiation striking the collector absorber. The theoretical water outlet temperature and efficiency are compared with experimental results and it shows good agreement between them. The main advantage of this collector is that inclination of collector does not have influence on performance of co-axial heat pipe solar collector therefore it can be positioned at any angle from horizontal to vertical. In high building where the roof area is not enough the co-axial heat pipe solar collectors can be installed on the roof as well as wall of the building. The other advantage is each heat pipe can be topologically disconnected from the manifold.

  9. Study of Using Solar Thermal Power for the Margarine Melting Heat Process.

    Science.gov (United States)

    Sharaf Eldean, Mohamed A; Soliman, A M

    2015-04-01

    The heating process of melting margarine requires a vast amount of thermal energy due to its high melting point and the size of the reservoir it is contained in. Existing methods to heat margarine have a high hourly cost of production and use fossil fuels which have been shown to have a negative impact on the environment. Thus, we perform an analytical feasibility study of using solar thermal power as an alternative energy source for the margarine melting process. In this study, the efficiency and cost effectiveness of a parabolic trough collector (PTC) solar field are compared with that of a steam boiler. Different working fluids (water vapor and Therminol-VP1 heat transfer oil (HTO)) through the solar field are also investigated. The results reveal the total hourly cost ($/h) by the conventional configuration is much greater than the solar applications regardless of the type of working fluid. Moreover, the conventional configuration causes a negative impact to the environment by increasing the amount of CO 2 , CO, and NO 2 by 117.4 kg/day, 184 kg/day, and 74.7 kg/day, respectively. Optimized period of melt and tank volume parameters at temperature differences not exceeding 25 °C are found to be 8-10 h and 100 m 3 , respectively. The solar PTC operated with water and steam as the working fluid is recommended as a vital alternative for the margarine melting heating process.

  10. Variability Characteristics of European Wind and Solar Power Resources—A Review

    Directory of Open Access Journals (Sweden)

    Ingeborg Graabak

    2016-06-01

    Full Text Available This paper reviews the most recent and relevant research into the variability characteristics of wind and solar power resources in Europe. The background for this study is that wind and solar resources will probably constitute major components of the future European power system. Such resources are variable, and EU plans to balance the variability with more grids and demand response. Thus, planning for the future power system requires an in-depth understanding of the variability. Resource variability is a multi-faceted concept best described using a range of distinct characteristics, and this review is structured on the basis of seven of these: Distribution Long-Term (hours to years, Distribution Short-Term (less than one hour, Step Changes, Autocorrelation, Spatial Correlation, Cross Correlation and Predictable Patterns. The review presents simulations and empirical results related to resource variability for each of these characteristics. Results to date reveal that the variability characteristics of the future power system is limited understood. This study recommends the development of a scheme for greater systematic assessment of variability. Such a scheme will contribute to the understanding of the impacts of variability and will make it possible to compare alternative power production portfolios and impacts of grid expansions, demand response and storage technologies.

  11. In-depth investigation of spin-on doped solar cells with thermally grown oxide passivation

    Directory of Open Access Journals (Sweden)

    Samir Mahmmod Ahmad

    Full Text Available Solar cell industrial manufacturing, based largely on proven semiconductor processing technologies supported by significant advancements in automation, has reached a plateau in terms of cost and efficiency. However, solar cell manufacturing cost (dollar/watt is still substantially higher than fossil fuels. The route to lowering cost may not lie with continuing automation and economies of scale. Alternate fabrication processes with lower cost and environmental-sustainability coupled with self-reliance, simplicity, and affordability may lead to price compatibility with carbon-based fuels. In this paper, a custom-designed formulation of phosphoric acid has been investigated, for n-type doping in p-type substrates, as a function of concentration and drive-in temperature. For post-diffusion surface passivation and anti-reflection, thermally-grown oxide films in 50–150-nm thickness were grown. These fabrication methods facilitate process simplicity, reduced costs, and environmental sustainability by elimination of poisonous chemicals and toxic gases (POCl3, SiH4, NH3. Simultaneous fire-through contact formation process based on screen-printed front surface Ag and back surface through thermally grown oxide films was optimized as a function of the peak temperature in conveyor belt furnace. Highest efficiency solar cells fabricated exhibited efficiency of ∼13%. Analysis of results based on internal quantum efficiency and minority carried measurements reveals three contributing factors: high front surface recombination, low minority carrier lifetime, and higher reflection. Solar cell simulations based on PC1D showed that, with improved passivation, lower reflection, and high lifetimes, efficiency can be enhanced to match with commercially-produced PECVD SiN-coated solar cells. Keywords: Crystalline Si solar cells, Phosphoric acid spin-on doping, Screen printing, Thermal oxide passivation

  12. Notes for a procedure of certification of thermal solar facilities; Apuntes para un procedimiento de certificacion de instalaciones solares termicas

    Energy Technology Data Exchange (ETDEWEB)

    Prieto, J. I.; Garcia, D.

    2008-07-01

    A procedure to evaluate the quality of solar thermal installations is proposed, following some analogy to the Calificacion Energetica de Viviendas (C.E.V.) method. The steps required to develop the method are established, analysing with special detail the stage of design-based qualification. The proposed procedures of energy saving qualification, architectural qualification, and economical qualification, are justified. Moreover, the report suggests a list of previous data that must be provided and periodically updated by the Administration to guarantee both the objectivity and the transparency of the qualification procedure. The exposure of the method is complemented with numerical and graphical application to several case studies. (Author)

  13. Solar thermal polymerase chain reaction for smartphone-assisted molecular diagnostics.

    Science.gov (United States)

    Jiang, Li; Mancuso, Matthew; Lu, Zhengda; Akar, Gunkut; Cesarman, Ethel; Erickson, David

    2014-02-20

    Nucleic acid-based diagnostic techniques such as polymerase chain reaction (PCR) are used extensively in medical diagnostics due to their high sensitivity, specificity and quantification capability. In settings with limited infrastructure and unreliable electricity, however, access to such devices is often limited due to the highly specialized and energy-intensive nature of the thermal cycling process required for nucleic acid amplification. Here we integrate solar heating with microfluidics to eliminate thermal cycling power requirements as well as create a simple device infrastructure for PCR. Tests are completed in less than 30 min, and power consumption is reduced to 80 mW, enabling a standard 5.5 Wh iPhone battery to provide 70 h of power to this system. Additionally, we demonstrate a complete sample-to-answer diagnostic strategy by analyzing human skin biopsies infected with Kaposi's Sarcoma herpesvirus (KSHV/HHV-8) through the combination of solar thermal PCR, HotSHOT DNA extraction and smartphone-based fluorescence detection. We believe that exploiting the ubiquity of solar thermal energy as demonstrated here could facilitate broad availability of nucleic acid-based diagnostics in resource-limited areas.

  14. Solar thermal polymerase chain reaction for smartphone-assisted molecular diagnostics

    Science.gov (United States)

    Jiang, Li; Mancuso, Matthew; Lu, Zhengda; Akar, Gunkut; Cesarman, Ethel; Erickson, David

    2014-02-01

    Nucleic acid-based diagnostic techniques such as polymerase chain reaction (PCR) are used extensively in medical diagnostics due to their high sensitivity, specificity and quantification capability. In settings with limited infrastructure and unreliable electricity, however, access to such devices is often limited due to the highly specialized and energy-intensive nature of the thermal cycling process required for nucleic acid amplification. Here we integrate solar heating with microfluidics to eliminate thermal cycling power requirements as well as create a simple device infrastructure for PCR. Tests are completed in less than 30 min, and power consumption is reduced to 80 mW, enabling a standard 5.5 Wh iPhone battery to provide 70 h of power to this system. Additionally, we demonstrate a complete sample-to-answer diagnostic strategy by analyzing human skin biopsies infected with Kaposi's Sarcoma herpesvirus (KSHV/HHV-8) through the combination of solar thermal PCR, HotSHOT DNA extraction and smartphone-based fluorescence detection. We believe that exploiting the ubiquity of solar thermal energy as demonstrated here could facilitate broad availability of nucleic acid-based diagnostics in resource-limited areas.

  15. Outdoor test method to determine the thermal behavior of solar domestic water heating systems

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Valladares, O.; Pilatowsky, I. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Privada Xochicalco, s/n, Colonia Centro, 62580 Temixco, Morelos (Mexico); Ruiz, V. [Escuela Tecnica Superior de Ingenieros, Universidad de Sevilla, Camino de los Descubrimientos, s/n, Isla de la Cartuja, 41092 Sevilla, Espana (Spain)

    2008-07-15

    The dynamics of the market, the generation of new promotion programs, fiscal incentives and many other factors are to be considered for the massive application of solar domestic water heating systems (SDWHS) mainly of the compact thermosiphon type, makes it necessary to choose simple and inexpensive procedure tests that permit to know their characteristic thermal behaviors without an official standard being necessary. Moreover, it allows the comparison among systems and offers enough and reliable information to consumers and manufacturers. In most developing countries, an official national standard for SDWHS is not available, therefore it is necessary to adopt an international test procedure in which the cost and time of implementation is very important. In this work, a simple and inexpensive test method to determine the thermal behavior of SDWHS is proposed. Even though these procedure tests do not have an official standard structure they permit, by comparing different solar systems under identical solar, ambient, and initial conditions, the experimental determination of: (a) the maximum available volume of water for solar heating; (b) water temperature increment and available thermal energy at the end of the day; (c) temperature profiles (stratification) and the average temperature in the storage tank after it is homogenized; (d) the average global thermal efficiency; (e) water temperature decrement and energy lost overnight; and (f) the relationship between hot water volume and solar collector area as function of the average heating temperature. An additional proposed test permits to know the heat losses caused by the reverse flow in the collector loop. These tests will be carried out independently of the configuration between the solar collector and the storage tank, the way the fluid circulates and the type of thermal exchange. The results of this procedure test can be very useful, firstly, for the local solar manufacturers' equipment in order to design

  16. Fast thermal cycling of acetanilide and magnesium chloride hexahydrate for indoor solar cooking

    Energy Technology Data Exchange (ETDEWEB)

    El-Sebaii, A.A.; Al-Amir, S.; Al-Marzouki, F.M.; Faidah, Adel S.; Al-Ghamdi, A.A.; Al-Heniti, S. [Physics Dept., Faculty of Science, King Abdul Aziz Univ., P.O. Box 80203, Jeddah 21589 (Saudi Arabia)

    2009-12-15

    Solar cookers are broadly divided into a direct or focusing type, indirect or box-type and advanced solar cookers. The focusing and box-type solar cookers are for outdoor applications. The advanced solar cookers have the advantage of being usable indoors and thus solve one of the problems, which impede the social acceptance of solar cookers. The advanced type solar cookers are employing additional solar units that increase the cost. Therefore, the solar cooker must contain a heat storage medium to store thermal energy for use during off-sunshine hours. The main aim of this study is to investigate the influence of the melting/solidification fast cycling of the commercial grade acetanilide C{sub 8}H{sub 9}NO (T{sub m} = 116 C) and magnesium chloride hexahydrate MgCl{sub 2}.6H{sub 2}O (T{sub m} = 116.7 C) on their thermo-physical properties; such as melting point and latent heat of fusion, to be used as storage media inside solar cookers. Five hundred cycles have been performed. The thermo-physical properties are measured using the differential scanning calorimetric technique. The compatibility of the selected phase change materials (PCMs) with the containing material is also studied via the surface investigation, using the SIM technique, of aluminum and stainless steel samples embedded in the PCM during cycling. It is inferred that acetanilide is a promising PCM for cooking indoors and during low intensity solar radiation periods with good compatibility with aluminum as a containing material. However, MgCl{sub 2}.6H{sub 2}O is not stable during its thermal cycling (even with the extra water principle) due to the phase segregation problem; therefore, it is not recommended as a storage material inside solar cookers for cooking indoors. It is also indicated that MgCl{sub 2}.6H{sub 2}O is not compatible with either aluminum or stainless steel. (author)

  17. Market potential and market hindrances for thermal solar energy; Marktpotentiale und Markthindernisse fuer die thermische Solarenergie

    Energy Technology Data Exchange (ETDEWEB)

    Gerheuser, F. W.

    2002-10-15

    This comprehensive report for the Swiss Federal Office of Energy (SFOE) discusses the market potential and market hindrances for thermal solar energy systems. The author notes that solar systems for heating domestic hot water have a considerable market potential, especially for single-family homes. Such installations are discussed in detail, whereby not only technicalities but also market image and the latent potential for such systems are discussed. The results of surveys made are presented and discussed. The lower potential for installations on apartment blocks is also mentioned.

  18. Diaryl-substituted norbornadienes with red-shifted absorption for molecular solar thermal energy storage.

    Science.gov (United States)

    Gray, Victor; Lennartson, Anders; Ratanalert, Phasin; Börjesson, Karl; Moth-Poulsen, Kasper

    2014-05-25

    Red-shifting the absorption of norbornadienes (NBDs), into the visible region, enables the photo-isomerization of NBDs to quadricyclanes (QCs) to be driven by sunlight. This is necessary in order to utilize the NBD-QC system for molecular solar thermal (MOST) energy storage. Reported here is a study on five diaryl-substituted norbornadienes. The introduced aryl-groups induce a significant red-shift of the UV/vis absorption spectrum of the norbornadienes, and device experiments using a solar-simulator set-up demonstrate the potential use of these compounds for MOST energy storage.

  19. New combined plant with integrated solar thermal energy; Neue Kombi-Anlage mit integrierter Solarwaerme

    Energy Technology Data Exchange (ETDEWEB)

    Leithner, R.; Dobrowolski, R.; Gresch, H. [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik

    1998-06-01

    In California there are already 350 MW{sub e} worth of solar thermal energy plants in operation on a more or less commercial basis. In these installations thermal oil in parabolic gutters is heated from 300 C to 400 C. The thermal oil passes its thermal energy on to a water vapour circuit via a heat exchanger. The water vapour circuit can also be heated with natural gas, for instance at night when solar energy is not available. However, as yet no existing plant fulfils all three of the following requirements: its construction should entail the lowest possible investment costs and it should be able to run without solar energy and without an expensive storage system; it should have the greatest possible efficiency, especially at times when solar energy is not available (e.g. at night); at the same time, the solar thermal energy should be harvested at the lowest possible temperature so as to make expensive concentrating equipment superfluous. These seemingly contradictory demands are now met by a new concept involving a combined gas and steam plant whose operation is based on the injection of water into the compressed air rather than on a high excess of air. This water is evaporated by solar thermal energy at temperatures below 170 C according to its partial pressure. [Deutsch] Es gibt bereits ueber 350 MWe solarthermische Anlagen in Kalifornien, die mehr oder weniger kommerziell betrieben werden. Bei diesen Anlagen wird Thermaloel von 300 C auf 400 C in Parabolrinnen erhitzt. In einem Waermetauscher gibt das Thermaloel die Waerme an einen Wasserdampfkreislauf ab, der auch mit Erdgas beheizt werden kann, wenn wie z.B. nachts keine Solarwaerme verfuegbar ist. In einem weiteren Schritt wurde vorgeschlagen, das Wasser direkt zu verdampfen. Keine dieser Anlagen genuegt jedoch gleichzeitig den folgenden drei Anforderungen: Die Anlage sollte mit moeglichst niedrigen Investitionskosten gebaut und auch ohne Solarwaerme bzw. ohne aufwendigen Speicher betrieben werden koennen

  20. Two-Axis Solar Heat Collection Tracker System for Solar Thermal Applications

    Directory of Open Access Journals (Sweden)

    Tsung-Chieh Cheng

    2013-01-01

    Full Text Available An experimental study was performed to investigate the effect of using a continuous operation two-axes tracking on the solar heat energy collected. This heat-collection sun tracking which LDR (light dependent resistor sensors installed on the Fersnel lens was used to control the tracking path of the sun with programming method of control with a closed loop system. The control hardware was connected to a computer through Zigbee wireless module and it also can monitor the whole tracking process information on a computer screen. An experimental study was performed to investigate the effect of using two-axes tracking on the solar heat energy collected. The results indicate that sun tracking systems are being increasingly employed to enhance the efficiency of heat collection by polar-axis tracking of the sun. Besides, the heating power was also measured by designed power measurement module at the different focal length of Fresnel lens, and the design of shadow mask of LDR sensors is an important factor for solar photothermal applications. Moreover, the results also indicated that the best time to obtain the largest solar irradiation power is during 11:00 –13:00  in Taiwan.

  1. Comparison of domestic olivine and European magnesite for electrically charged thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Laster, W.R.; Gay, B.M.; Palmour, H.; Schoenhals, R.J.

    1982-01-01

    Electrically charged thermal energy storage (TES) heaters employing high heat capacity ceramic refractories for sensible heat storage have been in use in Europe for several years. With these devices, low cost off-peak electrical energy is stored by heating a storage core composed of ceramic material to approximately 800/sup 0/C. During the peak period, no electrical energy is used as the building heating needs are supplied by extracting the stored energy from the core by forced air circulation. The recent increase in use of off-peak TES units in the U.S. has led to the search for a domestic supply of high heat capacity ceramic refractory material. North Carolina's extensive but underutilized supply of refractory grade olivine has been proposed as a source of storage material for these units. In this paper the suitability of North Carolina olivine for heat storage applications is assessed by comparing its thermal performance with that of European materials. Using the method of ASHRAE Standard 94.2, the thermal performance of two commercially available room-size TES units was determined experimentally with two different storage materials, North Carolina olivine and German magnesite. Comparisons are made and conclusions are drawn.

  2. Thermal Characterization of the Air Force Institute of Technology Solar Simulation Thermal Vacuum Chamber

    Science.gov (United States)

    2014-03-27

    reflectivity than water and because of snow and ice, greater latitudes have greater reflectivity. Albedo also tends to increase due to cloud cover and...15  Albedo Radiation ..................................................................................................... 16  Earth-Emitted Infrared...derivative control coefficient m mass, kg P pressure, Torr q heat rate, W combined direct and albedo solar heat rate absorbed by a spacecraft, W

  3. Effect of openings collectors and solar irradiance on the thermal efficiency of flat plate-finned collector for indirect-type passive solar dryer

    Science.gov (United States)

    Batubara, Fatimah; Dina, Sari Farah; Klaudia Kathryn Y., M.; Turmuzi, M.; Siregar, Fitri; Panjaitan, Nora

    2017-06-01

    Research on the effect of openings solar collector and solar irradiance to thermal efficiency has been done. Solar collector by flat plate-finned type consists of 3 ply insulator namely wood, Styrofoam and Rockwool with thickness respectively are 10 mm, 25 mm and 50 mm. Absorber plate made of aluminum sheet with thickness of 0.30 mm, painted by black-doff. Installation of 19 units fins (length x height x thickness: 1000x20x10 mm) on the collector will increase surface area of absorber so it can receive much more solar energy. The solar collector cover is made of glass (thickness of 5 mm). During the research, the solar irradiance and temperature of collector are measured and recorded every five minutes. Temperature measurement performed on the surface of the absorber plate, inside of collector, surface cover and the outer side insulator (plywood). This data is used to calculate the heat loss due to conduction, convection and radiation on the collector. Openings of collectors vary as follows: 100%, 75%, 15% and 0% (total enclosed). The data collecting was conducted from 09.00 am to 17.00 pm and triplicates. The collector thermal efficiency calculated based on the ratio of the amount of heat received to the solar irradiance absorbed. The results show that each of openings solar collector has different solar irradiance (because it was done on a different day) which is in units of W/m2: 390 (100% open), 376 (75% open), 429 (15% open), and 359 (totally enclosed). The highest thermal efficiency is in openings variation of 15% opened. These results indicate that the efficiency of the collector is influenced by the solar irradiance received by the collector and the temperature on the collector plate. The highest thermal efficiency is in variation of openings 15%. These indicate that the efficiency of the collector was influenced by solar irradiance received by the collector and openings of the collector plate.

  4. Novel Molten Salts Thermal Energy Storage for Concentrating Solar Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Ramana G. [Univ. of Alabama, Tuscaloosa, AL (United States)

    2013-10-23

    The explicit UA program objective is to develop low melting point (LMP) molten salt thermal energy storage media with high thermal energy storage density for sensible heat storage systems. The novel Low Melting Point (LMP) molten salts are targeted to have the following characteristics: 1. Lower melting point (MP) compared to current salts (<222ºC) 2. Higher energy density compared to current salts (>300 MJ/m3) 3. Lower power generation cost compared to current salt In terms of lower power costs, the program target the DOE's Solar Energy Technologies Program year 2020 goal to create systems that have the potential to reduce the cost of Thermal Energy Storage (TES) to less than $15/kWh-th and achieve round trip efficiencies greater than 93%. The project has completed the experimental investigations to determine the thermo-physical, long term thermal stability properties of the LMP molten salts and also corrosion studies of stainless steel in the candidate LMP molten salts. Heat transfer and fluid dynamics modeling have been conducted to identify heat transfer geometry and relative costs for TES systems that would utilize the primary LMP molten salt candidates. The project also proposes heat transfer geometry with relevant modifications to suit the usage of our molten salts as thermal energy storage and heat transfer fluids. The essential properties of the down-selected novel LMP molten salts to be considered for thermal storage in solar energy applications were experimentally determined, including melting point, heat capacity, thermal stability, density, viscosity, thermal conductivity, vapor pressure, and corrosion resistance of SS 316. The thermodynamic modeling was conducted to determine potential high temperature stable molten salt mixtures that have thermal stability up to 1000 °C. The thermo-physical properties of select potential high temperature stable (HMP) molten salt mixtures were also experimentally determined. All the salt mixtures align with the

  5. 3-D Modeling of Thermal Structure in Active Regions on the Solar Surface

    Science.gov (United States)

    Mok, Y.; Lionello, R.; Mikic, Z.; Linker, J.

    2001-05-01

    The thermal structure of a magnetically active region depends on a complicated balance between plasma heating, radiative cooling and the highly anisotropic thermal conduction guided by the magnetic field. It is also affected by plasma convection if siphon flows exist as a result of dynamic imbalance of pressure gradient, gravity and magnetic force. The difficulty of the numerical simulation lies in the wide ranges of density and temperature, separated by a narrow transition region with enormous gradients. Early studies of 1-D models (Mok et. al. 1991) provide a guidance on the thermal structure along individual field lines. A slightly more advanced 2-D model (Mok and Van Hoven 1993) produces a differential emission measure that is remarkably consistent with observations on the quiet sun. Active regions, however, require a 3-D model. We have implemented the necessary thermodynamics into our 3-D MHD code for this study. By starting with a magnetogram of an active region, we first establish an overlying magnetic structure. We then compute the thermal structure in the atmosphere. One of the most poorly understood physical processes in the energy balance is the plasma heating. We have computed the thermal structure based on various heating models and will compare their resulting emission measures. Mok, Schnack, and Van Hoven, 1991, Solar Phys. 132, 95. Mok and Van Hoven, 1993, Solar Phys. 146, 5. Work supported by the Sun Earth Connection Theory Program of NASA.

  6. Calculated thermal performance of solar collectors based on measured weather data from 2001-2010

    DEFF Research Database (Denmark)

    Dragsted, Janne; Furbo, Simon; Andersen, Elsa

    2015-01-01

    This paper presents an investigation of the differences in modeled thermal performance of solar collectors when meteorological reference years are used as input and when mulit-year weather data is used as input. The investigation has shown that using the Danish reference year based on the period...... 1975-1990 will result in deviations of up to 39 % compared with thermal performance calculated with multi-year the measured weather data. For the newer local reference years based on the period 2001-2010 the maximum deviation becomes 25 %. The investigation further showed an increase in utilization...

  7. Directory of the French thermal solar sector; Annuaire de la filiere francaise du solaire thermodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Demangeon, Elsa; Simmonet, Raphael; Canals, Jonathan

    2011-01-15

    After an overview of what is at stake for the thermal solar sector in terms of employment and industrial development, a discussion of the huge energy and industrial potential of this sector, and the proposition of a road map for the development of this sector in France, this publication proposes a directory of actors of the different activity sectors: research and development, engineering, electric and electronic hardware manufacturing, thermal equipment manufacturing, fluid manufacturing, reflector manufacturing, thermodynamic machine manufacturer, structure component manufacturer, control-command system, energy storage, developers, and so on

  8. Bypass Diode Temperature Tests of a Solar Array Coupon Under Space Thermal Environment Conditions

    Science.gov (United States)

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

    2016-01-01

    Tests were performed on a 56-cell Advanced Triple Junction solar array coupon whose purpose was to determine margin available for bypass diodes integrated with new, large multi-junction solar cells that are manufactured from a 4-inch wafer. The tests were performed under high vacuum with coupon back side thermal conditions of both cold and ambient. The bypass diodes were subjected to a sequence of increasing discrete current steps from 0 Amp to 2.0 Amp in steps of 0.25 Amp. At each current step, a temperature measurement was obtained via remote viewing by an infrared camera. This paper discusses the experimental methodology, experiment results, and the thermal model.

  9. Multi-objective genetic algorithm for the optimization of a flat-plate solar thermal collector.

    Science.gov (United States)

    Mayer, Alexandre; Gaouyat, Lucie; Nicolay, Delphine; Carletti, Timoteo; Deparis, Olivier

    2014-10-20

    We present a multi-objective genetic algorithm we developed for the optimization of a flat-plate solar thermal collector. This collector consists of a waffle-shaped Al substrate with NiCrOx cermet and SnO(2) anti-reflection conformal coatings. Optimal geometrical parameters are determined in order to (i) maximize the solar absorptance α and (ii) minimize the thermal emittance ε. The multi-objective genetic algorithm eventually provides a whole set of Pareto-optimal solutions for the optimization of α and ε, which turn out to be competitive with record values found in the literature. In particular, a solution that enables α = 97.8% and ε = 4.8% was found.

  10. Solar tests of aperture plate materials for solar thermal dish collectors

    Science.gov (United States)

    Jaffe, L. D.

    1983-08-01

    In parabolic dish solar collectors, walk-off of the spot of concentrated sunlight is a hazard if a malfunction causes the concentrator to stop following the Sun. Therefore, a test program was carried out to evaluate the behavior of various ceramics, metals, and polymers under solar irradiation of about 7000 kW/sq m. (peak) for 15 minutes. The only materials that did not slump or shatter were two grades of medium-grain extruded graphite. High purity, slip-cast silica might be satisfactory at somewhat lower flux. Oxidation of the graphite appeared acceptable during tests simulating walk-off, acquisition (2000 cycles on/off Sun), and spillage (continuous on-Sun operation).

  11. Thermal Performance Analysis of Solar Collectors Installed for Combisystem in the Apartment Building

    Science.gov (United States)

    Žandeckis, A.; Timma, L.; Blumberga, D.; Rochas, C.; Rošā, M.

    2012-01-01

    The paper focuses on the application of wood pellet and solar combisystem for space heating and hot water preparation at apartment buildings under the climate of Northern Europe. A pilot project has been implemented in the city of Sigulda (N 57° 09.410 E 024° 52.194), Latvia. The system was designed and optimised using TRNSYS - a dynamic simulation tool. The pilot project was continuously monitored. To the analysis the heat transfer fluid flow rate and the influence of the inlet temperature on the performance of solar collectors were subjected. The thermal performance of a solar collector loop was studied using a direct method. A multiple regression analysis was carried out using STATGRAPHICS Centurion 16.1.15 with the aim to identify the operational and weather parameters of the system which cause the strongest influence on the collector's performance. The parameters to be used for the system's optimisation have been evaluated.

  12. The application of simulation modeling to the cost and performance ranking of solar thermal power plants

    Science.gov (United States)

    Rosenberg, L. S.; Revere, W. R.; Selcuk, M. K.

    1981-01-01

    A computer simulation code was employed to evaluate several generic types of solar power systems (up to 10 MWe). Details of the simulation methodology, and the solar plant concepts are given along with cost and performance results. The Solar Energy Simulation computer code (SESII) was used, which optimizes the size of the collector field and energy storage subsystem for given engine-generator and energy-transport characteristics. Nine plant types were examined which employed combinations of different technology options, such as: distributed or central receivers with one- or two-axis tracking or no tracking; point- or line-focusing concentrator; central or distributed power conversion; Rankin, Brayton, or Stirling thermodynamic cycles; and thermal or electrical storage. Optimal cost curves were plotted as a function of levelized busbar energy cost and annualized plant capacity. Point-focusing distributed receiver systems were found to be most efficient (17-26 percent).

  13. Building America Best Practices Series, Volume 6: High-Performance Home Technologies: Solar Thermal & Photovoltaic Systems

    Energy Technology Data Exchange (ETDEWEB)

    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.

  14. Simulated Solar Flare X-Ray and Thermal Cycling Durability Evaluation of Hubble Space Telescope Thermal Control Candidate Replacement Materials

    Science.gov (United States)

    deGroh, Kim K.; Banks, Bruce A.; Sechkar, Edward A.; Scheiman, David A.

    1998-01-01

    During the Hubble Space Telescope (HST) second servicing mission (SM2), astronauts noticed that the multilayer insulation (MLI) covering the telescope was damaged. Large pieces of the outer layer of MLI (aluminized Teflon fluorinated ethylene propylene (Al-FEP)) were torn in several locations around the telescope. A piece of curled up Al-FEP was retrieved by the astronauts and was found to be severely embrittled, as witnessed by ground testing. Goddard Space Flight Center (GSFC) organized a HST MLI Failure Review Board (FRB) to determine the damage mechanism of FEP in the HST environment, and to recommend replacement insulation material to be installed on HST during the third servicing mission (SM3) in 1999. Candidate thermal control replacement materials were chosen by the FRB and tested for environmental durability under various exposures and durations. This paper describes durability testing of candidate materials which were exposed to charged particle radiation, simulated solar flare x-ray radiation and thermal cycling under load. Samples were evaluated for changes in solar absorptance and tear resistance. Descriptions of environmental exposures and durability evaluations of these materials are presented.

  15. Adsorption properties of porous materials for solar thermal energy storage and heat pump applications

    OpenAIRE

    Jänchen, Jochen; Stach, Helmut

    2012-01-01

    The water adsorption properties of modified porous sorbents for solar thermal energy storage and heat transformation have been investigated by thermogravimetry (TG) differential thermogravimetry (DTG), microcalorimetry, measurements of water adsorption isotherms, and storage tests. A chabazite type SAPO, a dealuminated faujasite type zeolite, and a mesostructured aluminosilicate, have been synthesized and compared with common zeolites X, Y and silica gel. It has been found that optimized latt...

  16. Sensitivity analysis of a community solar system using annual cycle thermal energy storage

    Science.gov (United States)

    Baylin, F.; Monte, R.; Sillman, S.

    The objective of this research is to assess the sensitivity of design parameters for a community solar heating system having annual thermal energy storage to factors including climate, building type, community size and collector type and inclination. The system under consideration uses a large, water-filled, concrete-constructed tank for providing space heating and domestic hot water (DHW). This presentation outlines results and conclusions about system sizing; a system design study and economic analysis are underway.

  17. Materials compatibility issues related to thermal energy storage for a space solar dynamic power system

    Science.gov (United States)

    Faget, N. M.

    1986-01-01

    Attention is given to results obtained to date in developmental investigations of a thermal energy storage (TES) system for the projected NASA Space Station's solar dynamic power system; these tests have concentrated on issues related to materials compatibility for phase change materials (PCMs) and their containment vessels' materials. The five PCMs tested have melting temperatures that correspond to the operating temperatures of either the Brayton or Rankine heat engines, which were independently chosen for their high energy densities.

  18. Power plant design with a combined cycle and double concentrated solar thermal power sources

    OpenAIRE

    Vidal i Parreu, Arnau

    2010-01-01

    The electricity has become an indispensable element of today’s society. Demand is growing continuously and the production is still based on limited sources of energy such as coal and petroleum derivate products. Environmental issues, such as global warming, and the uncertainty about the quantity of the conventional fossil fuels are forcing suppliers to find new solutions for the near future. In this assignment, concentrated solar thermal technologies for electricity generation could pla...

  19. High-Flux, High-Temperature Thermal Vacuum Qualification Testing of a Solar Receiver Aperture Shield

    Science.gov (United States)

    Kerslake, Thomas W.; Mason, Lee S.; Strumpf, Hal J.

    1997-01-01

    As part of the International Space Station (ISS) Phase 1 program, NASA Lewis Research Center (LERC) and the Russian Space Agency (RSA) teamed together to design, build and flight test the world's first orbital Solar Dynamic Power System (SDPS) on the Russian space station Mir. The Solar Dynamic Flight Demonstration (SDFD) program was to operate a nominal 2 kWe SDPS on Mir for a period up to 1-year starting in late 1997. Unfortunately, the SDFD mission was demanifested from the ISS phase 1 shuttle program in early 1996. However, substantial flight hardware and prototypical flight hardware was built including a heat receiver and aperture shield. The aperture shield comprises the front face of the cylindrical cavity heat receiver and is located at the focal plane of the solar concentrator. It is constructed of a stainless steel plate with a 1-m outside diameter, a 0.24-m inside diameter and covered with high-temperature, refractory metal Multi-Foil Insulation (MFI). The aperture shield must minimize heat loss from the receiver cavity, provide a stiff, high strength structure to accommodate shuttle launch loads and protect receiver structures from highly concentrated solar fluxes during concentrator off-pointing events. To satisfy Mir operational safety protocols, the aperture shield was required to accommodate direct impingement of the intensely concentrated solar image for a 1-hour period. To verify thermal-structural durability under the anticipated high-flux, high-temperature loading, an aperture shield test article was constructed and underwent a series of two tests in a large thermal vacuum chamber configured with a reflective, point-focus solar concentrator and a solar simulator. The test article was positioned near the focal plane and exposed to concentrated solar flux for a period of 1-hour. In the first test, a near equilibrium temperature of 1862 K was attained in the center of the shield hot spot. In the second test, with increased incident flux, a near

  20. Decay Resistance Variability of European Wood Species Thermally Modified by Industrial Process

    Directory of Open Access Journals (Sweden)

    Kevin CANDELIER

    2017-06-01

    Full Text Available Thermal modification is now considered as a new ecofriendly industrial wood modification process improving mainly the material decay resistance and its dimensional stability. Most industrial thermal treatment processes use convection heat transfer which induces sometimes heterogeneous treatment temperature propagation within the oven and lead to the heterogeneity in treatment efficiency. Thus, it is common that treatment is not completely effective on several stack boards, in a same batch. The aim of this paper was to study the decay resistance variability of various European wood species thermally modified. Thermal modifications were performed around 240°C during 4h, on about 10m3 of 27x152x2000mm3 wood planks placed in an industrial oven having a volume of 20m3 , on the following wood species: spruce, ash, beech and poplar. All of the tests concerning the decay resistance were carried out in the laboratory using untreated beech and pine woods as reference materials. An agar block test was used to determine the resistance of thermally modified woods, leached beforehand according to EN 84 standard or not, to brownrot and white-rot fungi, according to XP CEN/TS 15083-1. A large selection of treated wood samples was tested in order to estimate the variability of treatment efficiency. Thermal treatment increased the biological durability of all leached and un-leached modified wood samples, compared with native wood species. The treatment temperature of 240°C used in this study is sufficient to reach durability classes ‘‘durable’’ or ‘‘very durable’’ for the four wood species. However, the dispersion of weight loss values, due to the fungal attacks was very important and showed a large variability of the durability of wood which has been treated in a single batch. These results showed that there is a substantial need to develop process control and indicator in order to insure that the quality of treated timber is properly evaluated

  1. Optomechanical and thermal design of the Multi-Application Solar Telescope for USO

    Science.gov (United States)

    Denis, Stefan; Coucke, Pierre; Gabriel, Eric; Delrez, Christophe; Venkatakrishnan, Parameshwaran

    2008-07-01

    The Multi-Application Solar Telescope (MAST) is a 50 cm diameter class telescope to be installed on the Udaipur Solar Observatory's Island on the Lake Fatehsagar in Udaipur, India. It is dedicated to solar observation. The telescope is designed, manufactured, assembled and installed on-site by the belgian company AMOS SA for the Udaipur Solar Observatory (USO), an academic division of the Physical Research Laboratory (PRL) in India. Despite its limited size, the telescope is expected to be competitive with respect to worldwide large and costly projects thanks to its versatility regarding science goals and also thanks to its demanding optomechanical and thermal specification. This paper describes the optomechanical and thermal design of this telescope and presents solutions adopted by AMOS to meet the specific requirements. The optical configuration of the telescope is based on an afocal off-axis gregorian combination integrated on an Alt.-Az. mechanical mount, with a suite of flat folding mirrors to provide the required stationary collimated beam.

  2. Spectral splitting optimization for high-efficiency solar photovoltaic and thermal power generation

    Science.gov (United States)

    Bierman, David M.; Lenert, Andrej; Wang, Evelyn N.

    2016-12-01

    Utilizing the full solar spectrum is desirable to enhance the conversion efficiency of a solar power generator. In practice, this can be achieved through spectral splitting between multiple converters in parallel. However, it is unclear which wavelength bands should be directed to each converter in order to maximize the efficiency. We developed a model of an ideal hybrid solar converter which utilizes both a single-junction photovoltaic cell and a thermal engine. We determined the limiting efficiencies of this hybrid strategy and the corresponding optimum spectral bandwidth directed to the photovoltaic cell. This optimum width is inversely proportional to the thermal engine efficiency and scales with the bandgap of the photovoltaic cell. This bandwidth was also obtained analytically through an entropy minimization scheme and matches well with our model. We show that the maximum efficiency of the system occurs when it minimizes the spectral entropy generation. This concept can be extended to capture generalized non-idealities to increase the usefulness of this technique for a range of full solar spectrum utilization technologies.

  3. Thermal Storage Capacity and Night Ventilation Performance of a Solar Chimney Combined with Different PCMs

    Directory of Open Access Journals (Sweden)

    Jun Lu

    2017-01-01

    Full Text Available Thermal storage capacity and airflow rate of a solar chimney combined with different PCMs are numerically studied during nighttime. PCMs with phase change temperatures of 38°C, 44°C, 50°C, and 63°C are selected in this numerical study. Results show that the maximum average ventilation rate of 610 kg/m2 and maximum thermal storage of 4750 kJ/m2 are achieved at the phase change temperature of 38°C. However, for phase change temperature of 63°C, night ventilation does not occur under the identical conditions. The findings reveal that a lower phase change temperature can increase the chargeability (and therefore the dischargeability of a solar chimney, since a higher phase change temperature demands higher solar radiation intensity and longer charging time for a solar chimney. For PCM with a phase change temperature of 44°C, most of the heat stored in PCM is lost to ambient through glass cover by radiation and only a small portion is used for heating the air within air channel.

  4. Analysis of non-thermal velocities in the solar corona

    Directory of Open Access Journals (Sweden)

    L. Contesse

    2004-09-01

    Full Text Available We describe new ground-based spectroscopic observations made using a 40-cm aperture coronagraph over a whole range of radial distances (up to heights of 12' above the limb and along four different heliocentric directions N, E, S and W. The analysis is limited to the study of the brightest forbidden emission line of Fe XIV at 530.3nm, in order to reach the best possible signal-to-noise ratio. To make the results statistically more significant, the extracted parameters are averaged over the whole length of the slit, and measurements are repeated fives times at each position; the corresponding dispersions in the results obtained along the slit are given. Central line profile intensities and full line widths (FWHM are plotted and compared to measurements published by other authors closer to the limb. We found widths and turbulent (non-thermal velocities of significantly higher values above the polar regions, especially when a coronal hole is present along the line of sight. We do not see a definitely decreasing behaviour of widths and turbulent velocities in equatorial directions for larger radial distances, as reported in the literature, although lower values are measured compared to the values in polar regions. The variation in the high corona is rather flat and a correlation diagram indicates that it is different for different regions and different radial distances. This seems to be the first analysis of the profiles of this coronal line, up to large heights above the limb for both equatorial and polar regions.

  5. Expanding Thermal Plasma Chemical Vapour Deposition of ZnO:Al Layers for CIGS Solar Cells

    Directory of Open Access Journals (Sweden)

    K. Sharma

    2014-01-01

    Full Text Available Aluminium-doped zinc oxide (ZnO:Al grown by expanding thermal plasma chemical vapour deposition (ETP-CVD has demonstrated excellent electrical and optical properties, which make it an attractive candidate as a transparent conductive oxide for photovoltaic applications. However, when depositing ZnO:Al on CIGS solar cell stacks, one should be aware that high substrate temperature processing (i.e., >200°C can damage the crucial underlying layers/interfaces (such as CIGS/CdS and CdS/i-ZnO. In this paper, the potential of adopting ETP-CVD ZnO:Al in CIGS solar cells is assessed: the effect of substrate temperature during film deposition on both the electrical properties of the ZnO:Al and the eventual performance of the CIGS solar cells was investigated. For ZnO:Al films grown using the high thermal budget (HTB condition, lower resistivities, ρ, were achievable (~5 × 10−4 Ω·cm than those grown using the low thermal budget (LTB conditions (~2 × 10−3 Ω·cm, whereas higher CIGS conversion efficiencies were obtained for the LTB condition (up to 10.9% than for the HTB condition (up to 9.0%. Whereas such temperature-dependence of CIGS device parameters has previously been linked with chemical migration between individual layers, we demonstrate that in this case it is primarily attributed to the prevalence of shunt currents.

  6. Small-Scale Flat Plate Collectors for Solar Thermal Scavenging in Low Conductivity Environments

    Directory of Open Access Journals (Sweden)

    Emmanuel Ogbonnaya

    2017-01-01

    Full Text Available There is great opportunity to develop power supplies for autonomous application on the small scale. For example, remote environmental sensors may be powered through the harvesting of ambient thermal energy and heating of a thermoelectric generator. This work investigates a small-scale (centimeters solar thermal collector designed for this application. The absorber is coated with a unique selective coating and then studied in a low pressure environment to increase performance. A numerical model that is used to predict the performance of the collector plate is developed. This is validated based on benchtop testing of a fabricated collector plate in a low-pressure enclosure. Model results indicate that simulated solar input of about 800 W/m2 results in a collector plate temperature of 298 K in ambient conditions and up to 388 K in vacuum. The model also predicts the various losses in W/m2 K from the plate to the surroundings. Plate temperature is validated through the experimental work showing that the model is useful to the future design of these small-scale solar thermal energy collectors.

  7. Thermally Stable Silver Nanowires-Embedding Metal Oxide for Schottky Junction Solar Cells.

    Science.gov (United States)

    Kim, Hong-Sik; Patel, Malkeshkumar; Park, Hyeong-Ho; Ray, Abhijit; Jeong, Chaehwan; Kim, Joondong

    2016-04-06

    Thermally stable silver nanowires (AgNWs)-embedding metal oxide was applied for Schottky junction solar cells without an intentional doping process in Si. A large scale (100 mm(2)) Schottky solar cell showed a power conversion efficiency of 6.1% under standard illumination, and 8.3% under diffused illumination conditions which is the highest efficiency for AgNWs-involved Schottky junction Si solar cells. Indium-tin-oxide (ITO)-capped AgNWs showed excellent thermal stability with no deformation at 500 °C. The top ITO layer grew in a cylindrical shape along the AgNWs, forming a teardrop shape. The design of ITO/AgNWs/ITO layers is optically beneficial because the AgNWs generate plasmonic photons, due to the AgNWs. Electrical investigations were performed by Mott-Schottky and impedance spectroscopy to reveal the formation of a single space charge region at the interface between Si and AgNWs-embedding ITO layer. We propose a route to design the thermally stable AgNWs for photoelectric device applications with investigation of the optical and electrical aspects.

  8. Results of thermal performance evaluation of the Owens-Illinois sunpack liquid solar collector at indoor conditions

    Science.gov (United States)

    1979-01-01

    Test procedures and results of the thermal performance of a liquid, evacuated tube, solar collector under simulated conditions are presented. The collector tested was a module used on the early demonstration projects.

  9. Dynamic modeling of a solar receiver/thermal energy storage system based on a compartmented dense gas fluidized bed

    Science.gov (United States)

    Solimene, Roberto; Chirone, Roberto; Chirone, Riccardo; Salatino, Piero

    2017-06-01

    Fluidized beds may be considered a promising option to collection and storage of thermal energy of solar radiation in Concentrated Solar Power (CSP) systems thanks to their excellent thermal properties in terms of bed-to-wall heat transfer coefficient and thermal diffusivity and to the possibility to operate at much higher temperature. A novel concept of solar receiver for combined heat and power (CHP) generation consisting of a compartmented dense gas fluidized bed has been proposed to effectively accomplish three complementary tasks: collection of incident solar radiation, heat transfer to the working fluid of the thermodynamic cycle and thermal energy storage. A dynamical model of the system laid the basis for optimizing collection of incident radiative power, heat transfer to the steam cycle, storage of energy as sensible heat of bed solids providing the ground for the basic design of a 700kWth demonstration CSP plant.

  10. High Energy Advanced Thermal Storage for Spacecraft Solar Thermal Power and Propulsion Systems

    Science.gov (United States)

    2011-10-12

    on the fiberglass dish template failed due to difficulties in controlling extra reactions during chemical spraying . This degraded the clear coat...enough to allow relatively large thermal gradients during the heating process. Pyrolytic BN is favorable material for future crucible designs that

  11. The thermal environment of the fiber glass dome for the new solar telescope at Big Bear Solar Observatory

    Science.gov (United States)

    Verdoni, A. P.; Denker, C.; Varsik, J. R.; Shumko, S.; Nenow, J.; Coulter, R.

    2007-09-01

    The New Solar Telescope (NST) is a 1.6-meter off-axis Gregory-type telescope with an equatorial mount and an open optical support structure. To mitigate the temperature fluctuations along the exposed optical path, the effects of local/dome-related seeing have to be minimized. To accomplish this, NST will be housed in a 5/8-sphere fiberglass dome that is outfitted with 14 active vents evenly spaced around its perimeter. The 14 vents house louvers that open and close independently of one another to regulate and direct the passage of air through the dome. In January 2006, 16 thermal probes were installed throughout the dome and the temperature distribution was measured. The measurements confirmed the existence of a strong thermal gradient on the order of 5° Celsius inside the dome. In December 2006, a second set of temperature measurements were made using different louver configurations. In this study, we present the results of these measurements along with their integration into the thermal control system (ThCS) and the overall telescope control system (TCS).

  12. Solar Thermal Conversion of Biomass to Synthesis Gas: Cooperative Research and Development Final Report, CRADA Number CRD-09-00335

    Energy Technology Data Exchange (ETDEWEB)

    Netter, J.

    2013-08-01

    The CRADA is established to facilitate the development of solar thermal technology to efficiently and economically convert biomass into useful products (synthesis gas and derivatives) that can replace fossil fuels. NREL's High Flux Solar Furnace will be utilized to validate system modeling, evaluate candidate reactor materials, conduct on-sun testing of the process, and assist in the development of solar process control system. This work is part of a DOE-USDA 3-year, $1M grant.

  13. MoO3 Thickness, Thermal Annealing and Solvent Annealing Effects on Inverted and Direct Polymer Photovoltaic Solar Cells

    OpenAIRE

    Guillaume Wantz; Lionel Hirsch; Bertrand Pavageau; Michel Lahaye; Lionel Derue; Sylvain Chambon

    2012-01-01

    16 pages; International audience; Several parameters of the fabrication process of inverted polymer bulk heterojunction solar cells based on titanium oxide as an electron selective layer and molybdenum oxide as a hole selective layer were tested in order to achieve efficient organic photovoltaic solar cells. Thermal annealing treatment is a common process to achieve optimum morphology, but it proved to be damageable for the performance of this kind of inverted solar cells. We demonstrate usin...

  14. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption...

  15. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    2011-01-01

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption...

  16. Thermal-Structural Analysis of PICA Tiles for Solar Tower Test

    Science.gov (United States)

    Agrawal, Parul; Empey, Daniel M.; Squire, Thomas H.

    2009-01-01

    Thermal protection materials used in spacecraft heatshields are subjected to severe thermal and mechanical loading environments during re-entry into earth atmosphere. In order to investigate the reliability of PICA tiles in the presence of high thermal gradients as well as mechanical loads, the authors designed and conducted solar-tower tests. This paper presents the design and analysis work for this tests series. Coupled non-linear thermal-mechanical finite element analyses was conducted to estimate in-depth temperature distribution and stress contours for various cases. The first set of analyses performed on isolated PICA tile showed that stresses generated during the tests were below the PICA allowable limit and should not lead to any catastrophic failure during the test. The tests results were consistent with analytical predictions. The temperature distribution and magnitude of the measured strains were also consistent with predicted values. The second test series is designed to test the arrayed PICA tiles with various gap-filler materials. A nonlinear contact method is used to model the complex geometry with various tiles. The analyses for these coupons predict the stress contours in PICA and inside gap fillers. Suitable mechanical loads for this architecture will be predicted, which can be applied during the test to exceed the allowable limits and demonstrate failure modes. Thermocouple and strain-gauge data obtained from the solar tower tests will be used for subsequent analyses and validation of FEM models.

  17. MEASUREMENTS OF NON-THERMAL LINE WIDTHS IN SOLAR ACTIVE REGIONS

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, David H. [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2016-03-20

    Spectral line widths are often observed to be larger than can be accounted for by thermal and instrumental broadening alone. This excess broadening is a key observational constraint for both nanoflare and wave dissipation models of coronal heating. Here we present a survey of non-thermal velocities measured in the high temperature loops (1–4 MK) often found in the cores of solar active regions. This survey of Hinode Extreme Ultraviolet Imaging Spectrometer (EIS) observations covers 15 non-flaring active regions that span a wide range of solar conditions. We find relatively small non-thermal velocities, with a mean value of 17.6 ± 5.3 km s{sup −1}, and no significant trend with temperature or active region magnetic flux. These measurements appear to be inconsistent with those expected from reconnection jets in the corona, chromospheric evaporation induced by coronal nanoflares, and Alfvén wave turbulence models. Furthermore, because the observed non-thermal widths are generally small, such measurements are difficult and susceptible to systematic effects.

  18. Mathematical model for solar drying of potato cylinders with thermal conductivity radially modulated

    Science.gov (United States)

    Trujillo Arredondo, Mariana

    2014-05-01

    A mathematical model for drying potato cylinders using solar radiation is proposed and solved analytically. The model incorporates the energy balance for the heat capacity of the potato, the radiation heat transfer from the potato toward the drying chamber and the solar radiation absorbed by the potato during the drying process. Potato cylinders are assumed to exhibit a thermal conductivity which is radially modulated. The method of the Laplace transform, with integral Bromwich and residue theorem will be applied and the analytic solutions for the temperature profiles in the potato cylinder will be derived in the form of an infinite series of Bessel functions, when the thermal conductivity is constant; and in the form of an infinite series of Heun functions, when the thermal conductivity has a linear radial modulation. All computations are performed using computer algebra, specifically Maple. It is expected that the analytical results obtained will be useful in food engineering and industry. Our results suggest some lines for future investigations such as the adoption of more general forms of radial modulation for the thermal conductivity of potato cylinders; and possible applications of other computer algebra software such as Maxima and Mathematica.

  19. Molecularly Engineered Azobenzene Derivatives for High Energy Density Solid-State Solar Thermal Fuels.

    Science.gov (United States)

    Cho, Eugene N; Zhitomirsky, David; Han, Grace G D; Liu, Yun; Grossman, Jeffrey C

    2017-03-15

    Solar thermal fuels (STFs) harvest and store solar energy in a closed cycle system through conformational change of molecules and can release the energy in the form of heat on demand. With the aim of developing tunable and optimized STFs for solid-state applications, we designed three azobenzene derivatives functionalized with bulky aromatic groups (phenyl, biphenyl, and tert-butyl phenyl groups). In contrast to pristine azobenzene, which crystallizes and makes nonuniform films, the bulky azobenzene derivatives formed uniform amorphous films that can be charged and discharged with light and heat for many cycles. Thermal stability of the films, a critical metric for thermally triggerable STFs, was greatly increased by the bulky functionalization (up to 180 °C), and we were able to achieve record high energy density of 135 J/g for solid-state STFs, over a 30% improvement compared to previous solid-state reports. Furthermore, the chargeability in the solid state was improved, up to 80% charged from 40% charged in previous solid-state reports. Our results point toward molecular engineering as an effective method to increase energy storage in STFs, improve chargeability, and improve the thermal stability of the thin film.

  20. Analysis of Medium-Scale Solar Thermal Systems and Their Potential in Lithuania

    Directory of Open Access Journals (Sweden)

    Rokas Valančius

    2015-06-01

    Full Text Available Medium-scale solar hot water systems with a total solar panel area varying from 60 to 166 m2 have been installed in Lithuania since 2002. However, the performance of these systems varies depending on the type of energy users, equipment and design of the systems, as well as their maintenance. The aim of this paper was to analyse operational SHW systems from the perspective of energy production and economic benefit as well as to outline the differences of their actual performance compared to the numerical simulation results. Three different medium-scale solar thermal systems in Lithuania were selected for the analysis varying in both equipment used (flat type solar collectors, evacuated tube collectors and type of energy user (swimming pool building, domestic hot water heating, district heating. The results of the analysis showed that in the analysed cases the gap between measured and modelled data of heat energy produced by SHW systems was approx. 11%. From the economical perspective, the system with flat type solar collectors used for domestic hot water production was proved to be most efficient. However, calculation of Internal Rate of Return showed that a grant of 35% is required for this project to be fully profitable.

  1. Thermal power generation projects ``Large Scale Solar Heating``; EU-Thermie-Projekte ``Large Scale Solar Heating``

    Energy Technology Data Exchange (ETDEWEB)

    Kuebler, R.; Fisch, M.N. [Steinbeis-Transferzentrum Energie-, Gebaeude- und Solartechnik, Stuttgart (Germany)

    1998-12-31

    The aim of this project is the preparation of the ``Large-Scale Solar Heating`` programme for an Europe-wide development of subject technology. The following demonstration programme was judged well by the experts but was not immediately (1996) accepted for financial subsidies. In November 1997 the EU-commission provided 1,5 million ECU which allowed the realisation of an updated project proposal. By mid 1997 a small project was approved, that had been requested under the lead of Chalmes Industriteteknik (CIT) in Sweden and is mainly carried out for the transfer of technology. (orig.) [Deutsch] Ziel dieses Vorhabens ist die Vorbereitung eines Schwerpunktprogramms `Large Scale Solar Heating`, mit dem die Technologie europaweit weiterentwickelt werden sollte. Das daraus entwickelte Demonstrationsprogramm wurde von den Gutachtern positiv bewertet, konnte jedoch nicht auf Anhieb (1996) in die Foerderung aufgenommen werden. Im November 1997 wurden von der EU-Kommission dann kurzfristig noch 1,5 Mio ECU an Foerderung bewilligt, mit denen ein aktualisierter Projektvorschlag realisiert werden kann. Bereits Mitte 1997 wurde ein kleineres Vorhaben bewilligt, das unter Federfuehrung von Chalmers Industriteknik (CIT) in Schweden beantragt worden war und das vor allem dem Technologietransfer dient. (orig.)

  2. An overview of the value of parabolic dish solar thermal systems in industrial cogeneration applications

    Science.gov (United States)

    1982-01-01

    The essential elements of the cogeneration system configuration to be captured were the displacement of thermal energy by collection and use of the Brayton exhaust stream, and the sale back to the utility of any electricity production in excess of on-site requirements. In contrast to simply dumping these energy flows, their use or sale obviously serves, by itself, to increase gross value of the solar thermal energy system. Net allowable cost of the parabolic dish modules may or may not be increased, however. A consideration is that the waste heat capture and delivery subsystems are not free. This study does not address the incremental cost of adding waste heat capture, transport, and conversion (to steam, if necessary). It does compute a value for the thermal energy thereby displaced. This value can serve as a first-round input to any detailed economic evaluation of waste heat recovery.

  3. Solid state phase change materials for thermal energy storage in passive solar heated buildings

    Science.gov (United States)

    Benson, D. K.; Christensen, C.

    1983-11-01

    A set of solid state phase change materials was evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol, pentaglycerine and neopentyl glycol. Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature within the range from less than 25 deg to 188 deg. Thermophysical properties such as thermal conductivity, density and volumetric expansion were measured. Computer simulations were used to predict the performance of various Trombe wall designs incorporating solid state phase change materials. Optimum performance was found to be sensitive to the choice of phase change temperatures and to the thermal conductivity of the phase change material. A molecular mechanism of the solid state phase transition is proposed and supported by infrared spectroscopic evidence.

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

    Science.gov (United States)

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

    1980-01-01

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

  5. High Temperature Latent Heat Thermal Energy Storage to Augment Solar Thermal Propulsion for Microsatellites

    Science.gov (United States)

    2015-08-30

    heat of fusion . In this work, boron is considered a long-term high performance solution and silicon is presented as a near term development target with... conceptual studies. However, there have been no thorough investigations due to the absence of existing research in addition to cost and schedule constraints...driven by a nuclear thermal energy source. Zubrin et al. proposed a “bi-modal” approach which modified an existing 40 kWe nuclear-thermionic reactor

  6. EVALUATION OF FLAT-PLATE PHOTOVOLTAIC THERMAL HYBRID SYSTEMS FOR SOLAR ENERGY UTILIZATION.

    Energy Technology Data Exchange (ETDEWEB)

    ANDREWS,J.W.

    1981-06-01

    The technical and economic attractiveness of combined photovoltaic/thermal (PV/T) solar energy collectors was evaluated. The study was limited to flat-plate collectors since concentrating photovoltaic collectors require active cooling and thus are inherently PV/T collectors, the only decision being whether to use the thermal energy or to dump it. it was also specified at the outset that reduction in required roof area was not to be used as an argument for combining the collection of thermal and electrical energy into one module. Three tests of economic viability were identified, all of which PV/T must pass if it is to be considered a promising alternative: PV/T must prove to be competitive with photovoltaic-only, thermal-only, and side-by-side photovoltaic-plus-thermal collectors and systems. These three tests were applied to systems using low-temperature (unglazed) collectors and to systems using medium-temperature (glazed) collectors in Los Angeles, New York, and Tampa. For photovoltaics, the 1986 DOE cost goals were assumed to have been realized, and for thermal energy collection two technologies were considered: a current technology based on metal and glass, and a future technology based on thin-film plastics. The study showed that for medium-temperature applications PV/T is not an attractive option in any of the locations studied. For low-temperature applications, PV/T appears to be marginally attractive.

  7. Thermal Analysis and Correlation of the Mars Odyssey Spacecraft's Solar Array During Aerobraking Operations

    Science.gov (United States)

    Dec, John A.; Gasbarre, Joseph F.; George, Benjamin E.

    2002-01-01

    The Mars Odyssey spacecraft made use of multipass aerobraking to gradually reduce its orbit period from a highly elliptical insertion orbit to its final science orbit. Aerobraking operations provided an opportunity to apply advanced thermal analysis techniques to predict the temperature of the spacecraft's solar array for each drag pass. Odyssey telemetry data was used to correlate the thermal model. The thermal analysis was tightly coupled to the flight mechanics, aerodynamics, and atmospheric modeling efforts being performed during operations. Specifically, the thermal analysis predictions required a calculation of the spacecraft's velocity relative to the atmosphere, a prediction of the atmospheric density, and a prediction of the heat transfer coefficients due to aerodynamic heating. Temperature correlations were performed by comparing predicted temperatures of the thermocouples to the actual thermocouple readings from the spacecraft. Time histories of the spacecraft relative velocity, atmospheric density, and heat transfer coefficients, calculated using flight accelerometer and quaternion data, were used to calculate the aerodynamic heating. During aerobraking operations, the correlations were used to continually update the thermal model, thus increasing confidence in the predictions. This paper describes the thermal analysis that was performed and presents the correlations to the flight data.

  8. Implications of Switching Fossil Fuel Subsidies to Solar: A Case Study for the European Union

    Directory of Open Access Journals (Sweden)

    Jon Sampedro

    2017-12-01

    Full Text Available Fossil fuel subsidies (FFS constitute one of the most obvious barriers to tackling climate change, as they encourage inefficient energy consumption and divert investment away from clean energy sources. According to the International Monetary Fund, FFS amounted globally to $233 billion in 2014, over four times the value of subsidies awarded to promote renewable energy. In this study an integrated assessment model is used to analyse the CO2 implications in the European Union of eliminating FFS and recycling the revenues to promote rooftop PV. It is found that eliminating FFS would give rise to a small reduction in CO2 due to fuel-switching from coal to gas. If the revenues were recycled to promote solar, then the CO2 reduction would increase from 1.8% to 2.2% by 2030. Eliminating FFS is not a panacea from the mitigation point of view, even if the revenues are recycled, but other important objectives, such as those related to renewable energy promotion and the reduction of air pollution, are advanced at zero cost for the government.

  9. A short term test method for large installed solar thermal systems

    Energy Technology Data Exchange (ETDEWEB)

    Beikircher, T.; Benz, N.; Gut, M. [Bavarian Centre for Applied Energy Research, Div. Solar Thermal and Biomass, Munich (Germany); Drueck, H. [Univ. Stuttgart, Inst. fuer Thermodynamik und Waermetechnik, Stuttgart (Germany)

    2000-07-01

    In order to determine the yearly energy output of solar thermal systems, we developed a quick, reliable and low-cost short term test method (ISTT-procedure), based on the adaptation of a dynamic, component based simulation model to transient measuring data from about 6 weeks. The method is especially helpful to quickly judge the fulfilments of contracts concerned with guaranteed solar results (GSR). On the experimental side, an autarkic wireless measuring station for the meteorological quantities has been developed, new surface temperature sensors have been constructed and ultrasonic volume flow gauges as well as a mobile magnetic inductive volume flow station have been applied. Thus expensive wiring and cutting off the fluid circuits can be avoided. For the dynamic evaluation procedure, we tested different simulation programs using the multi-port store model with four free parameters and an extended matched flow collector model with eight free parameters including pipes and a heat exchanger. Criteria for a measuring sequence sufficient for a reliable parameter identification and experimental procedures for their realization have been deduced and the parameters were numerically identified from insitu-measuring sequences not exceeding 6 weeks. The ISTT- procedure allows to separate the influence of the operation conditions (weather and hot water demand) from the performance of the solar system. It is possible to predict the yearly solar energy gain for arbitrary standard operation conditions, especially for those supposed by the planner. In this paper, the ISTT-procedure is generally described and exemplary carried out and validated for a large solar thermal system with 110 m{sup 2} flat-plate-collectors. The results of the ISTT-method excellently agree to independent long-term measurements for the energy delivered by the collector field (GSR 1) as well as for the energy discharged from the buffer store (GSR2). (au)

  10. Potential Applications of Concentrated Solar Thermal Technologies in the Australian Minerals Processing and Extractive Metallurgical Industry

    Science.gov (United States)

    Eglinton, Thomas; Hinkley, Jim; Beath, Andrew; Dell'Amico, Mark

    2013-12-01

    The Australian minerals processing and extractive metallurgy industries are responsible for about 20% of Australia's total greenhouse gas (GHG) emissions. This article reviews the potential applications of concentrated solar thermal (CST) energy in the Australian minerals processing industry to reduce this impact. Integrating CST energy into these industries would reduce their reliance upon conventional fossil fuels and reduce GHG emissions. As CST technologies become more widely deployed and cheaper, and as fuel prices rise, CST energy will progressively become more competitive with conventional energy sources. Some of the applications identified in this article are expected to become commercially competitive provided the costs for pollution abatement and GHG mitigation are internalized. The areas of potential for CST integration identified in this study can be classed as either medium/low-temperature or high-temperature applications. The most promising medium/low-grade applications are electricity generation and low grade heating of liquids. Electricity generation with CST energy—also known as concentrated solar power—has the greatest potential to reduce GHG emissions out of all the potential applications identified because of the 24/7 dispatchability when integrated with thermal storage. High-temperature applications identified include the thermal decomposition of alumina and the calcination of limestone to lime in solar kilns, as well as the production of syngas from natural gas and carbonaceous materials for various metallurgical processes including nickel and direct reduced iron production. Hybridization and integration with thermal storage could enable CST to sustain these energy-intensive metallurgical processes continuously. High-temperature applications are the focus of this paper.

  11. Single bi-temperature thermal storage tank for application in solar thermal plant

    Science.gov (United States)

    Litwin, Robert Zachary; Wait, David; Lancet, Robert T.

    2017-05-23

    Thermocline storage tanks for solar power systems are disclosed. A thermocline region is provided between hot and cold storage regions of a fluid within the storage tank cavity. One example storage tank includes spaced apart baffles fixed relative to the tank and arranged within the thermocline region to substantially physically separate the cavity into hot and cold storage regions. In another example, a flexible baffle separated the hot and cold storage regions and deflects as the thermocline region shifts to accommodate changing hot and cold volumes. In yet another example, a controller is configured to move a baffle within the thermocline region in response to flow rates from hot and cold pumps, which are used to pump the fluid.

  12. The physical environment and occupant thermal perceptions in office buildings. An evaluation of sampled data from five European countries

    Energy Technology Data Exchange (ETDEWEB)

    Stoops, J.L. [Chalmers Univ. of Tech., Goeteborg (Sweden). Dept. of Building Services Engineering

    2002-02-01

    The results from a large field study of thermal comfort in European office buildings are reported. Measurements of physical environmental conditions and occupant perceptions were collected over sixteen months from twenty-six different office buildings located in France, Greece, Portugal, Sweden and the UK. This thesis focuses on the physical environmental measurements and occupant thermal perceptions; however, additional variables with connections to environmental satisfaction are also examined. An overview of human comfort theory is presented to help place this thesis in appropriate context. The overview presents thermal comfort issues within a broad framework of human response to the environment including physical, physiological. behavioural, psychological and other variables. A more narrowly focused overview of current thermal comfort research is also included. The work attempts to show relationships and produce useful information from the data set using graphical methods, especially lowess, a locally weighted regression based scatter plot smoothing technique. The objective of using this approach is to literally show the relationships visually. This approach allows the data set itself to illustrate the actual thermal conditions in European office buildings and the occupant perceptions of those conditions along with illustrating relationships. The data is examined in some detail with key relationships identified and explored. Significant differences between countries, both for the physical conditions and the perceptions of those conditions are identified. In addition, the variation over the course of the year for each country is explored. The relationship of daily average outdoor temperatures to indoor temperatures and indoor temperature perceptions is found to be critically important. The relationships, which appear to drive perceptions of thermal comfort, occur in complex ways, making simple, all encompassing explanations impossible. The nature and size of the

  13. High Temperature Latent Heat Thermal Energy Storage to Augment Solar Thermal Propulsion for Microsatellites

    Science.gov (United States)

    2014-03-01

    assumptions of  iso thermal test sections  were inaccurate • Demonstrated shielding efficiency of approx.  55% with hand polished aluminum shields • Must...Calculations TWO IMPULSE ONE PERIGEE BURN ONE APOGEE BURN TIW > 0.01 .. ’• ’ \\ ’ ’ ’ • (!),/ LEO TO GEO 14000 ~ I!N < 17000 FPS TRIP TIME < DAY...I MULTI I MPU SE MORE THAN ONf PER I GEE BURNS AND PWRE THAN ON£ nlNSERTJON" BURNS NEAR FINAL APOGEE LEO TO GEO 14000 ~ /lV ~ 19200 FPS TRIP

  14. Solar thermal OTV—Applications to reusable and expendable launch vehicles

    Science.gov (United States)

    Kassler, Thomas L.; Frye, Patrick; Partch, Russ

    2000-07-01

    The Solar Orbit Transfer Vehicle (SOTV) program being sponsored by the U.S. Air Force Research Laboratory (AFRL) is developing technology that will engender revolutionary benefits to satellites and orbitto-orbit transfer systems. Solar thermal propulsion offers significant advantages for near-term expendable launch vehicles (ELVs) such as Delta IV, mid- to farterm reusable launch vehicles (RLVs) and ultimately to manned exploration of the Moon and Mars. Solar thermal propulsion uses a relatively large mirrored concentrator to focus solar energy onto a compact absorber, which is in turn heated to > 2200 K. This heat can then be used in two major ways. By flowing hydrogen or another working fluid through the absorber, high efficiency thrust can be generated with 800 sec or more specific impulse (Isp), almost twice that of conventional cryogenic stages and comparable with typical solid-core nuclear thermal stages. Within a decade, advances in materials and fabrication processes hold the promise of the Isp ranging up to 1,100 sec. In addition, attached thermionic or alkali metal thermoelectric converter (AMTEC) power converters can be used to generate 20 to 100 kilowatts (kW) of electricity. The SOTV Space Experiment (SOTV-SE), planned to be flown in 2003, will demonstrate both hydrogen propulsion and thermionic power generation, including advanced lightweight deployable concentrators suitable for large-scale applications. Evolutionary geosynchronous-transfer orbit/ geosynchronous-Earth orbit (GTO/GEO) payload lift capability improvements of 50% or more to the Delta IV launch vehicles could be implemented as part of the Delta IV P4I plan shortly thereafter. Beyond that, SOTV technology should allow long-term storage of stages in orbits up to GEO with tremendous maneuvering capability, potentially 4 to 5 km/sec or more. Servicing of low-Earth orbit (LEO) and GEO assets and reusable (ROTVs) are other possible applications. Offering a combination of high Isp and high

  15. Thermal analysis and performance optimization of a solar hot water plant with economic evaluation

    KAUST Repository

    Kim, Youngdeuk

    2012-05-01

    The main objective of this study is to optimize the long-term performance of an existing active-indirect solar hot water plant (SHWP), which supplies hot water at 65 °C for use in a flight kitchen, using a micro genetic algorithm in conjunction with a relatively detailed model of each component in the plant and solar radiation model based on the measured data. The performance of SHWP at Changi International Airport Services (CIASs), Singapore, is studied for better payback period using the monthly average hourly diffuse and beam radiations and ambient temperature data. The data input for solar radiation model is obtained from the Singapore Meteorological Service (SMS), and these data have been compared with long-term average data of NASA (surface meteorology and solar energy or SSE). The comparison shows a good agreement between the predicted and measured hourly-averaged, horizontal global radiation. The SHWP at CIAS, which comprises 1200m 2 of evacuated-tube collectors, 50m 3 water storage tanks and a gas-fired auxiliary boiler, is first analyzed using a baseline configuration, i.e., (i) the local solar insolation input, (ii) a coolant flow rate through the headers of collector based on ASHRAE standards, (iii) a thermal load demand pattern amounting to 100m 3/day, and (iv) the augmentation of water temperature by auxiliary when the supply temperature from solar tank drops below the set point. A comparison between the baseline configuration and the measured performance of CIAS plant gives reasonably good validation of the simulation code. Optimization is further carried out for the following parameters, namely; (i) total collector area of the plant, (ii) storage volume, and (iii) three daily thermal demands. These studies are performed for both the CIAS plant and a slightly modified plant where the hot water supply to the load is adjusted constant at times when the water temperature from tank may exceed the set temperature. It is found that the latter

  16. Harmonization of standards for parabolic trough collector testing in solar thermal power plants

    Science.gov (United States)

    Sallaberry, Fabienne; Valenzuela, Loreto; Palacin, Luis G.; Leon, Javier; Fischer, Stephan; Bohren, Andreas

    2017-06-01

    The technology of parabolic trough collectors (PTC) is used widely in concentrating Solar Power (CSP) plants worldwide. However this type of large-size collectors cannot be officially tested by an accredited laboratory and certified by an accredited certification body so far, as there is no standard adapted to its particularity, and the current published standard for solar thermal collectors are not completely applicable to them. Recently some standardization committees have been working on this technology. This paper aims to give a summary of the standardized testing methodology of large-size PTC for CSP plants, giving the physical model chosen for modeling the thermal performance of the collector in the new revision of standard ISO 9806 and the points still to be improved in the standard draft IEC 62862-3-2. In this paper, a summary of the testing validation performed on one parabolic trough collector installed in one of the test facilities at the Plataforma Solar de Almería (PSA) with this new model is also presented.

  17. Thermal Efficiency of Power Module “Boiler with Solar Collectors as Additional Heat Source” For Combined Heat Supply System

    Directory of Open Access Journals (Sweden)

    Denysova A.E.

    2015-04-01

    Full Text Available The purpose of work is to increase the efficiency of the combined heat supply system with solar collectors as additional thermal generators. In order to optimize the parameters of combined heat supply system the mathematical modeling of thermal processes in multi module solar collectors as additional thermal generators for preheating of the water for boiler have been done. The method of calculation of multi-module solar collectors working with forced circulation for various configurations of hydraulic connection of solar collector modules as the new result of our work have been proposed. The results of numerical simulation of thermal efficiency of solar heat source for boiler of combined heat supply system with the account of design features of the circuit; regime parameters of thermal generators that allow establishing rational conditions of its functioning have been worked out. The conditions of functioning that provide required temperature of heat carrier incoming to boiler and value of flow rate at which the slippage of heat carrier is not possible for different hydraulic circuits of solar modules have been established.

  18. Thermal properties of high temperature vacuum receivers used for parabolic trough solar thermal power system

    Directory of Open Access Journals (Sweden)

    Qinghe Yu

    2017-08-01

    Full Text Available The receiver's emittance and vacuum pressure are the two of great significance issues on the heat-loss which is the main factor reducing the efficiency of the parabolic though systems. In this paper, the thermal steady-state equilibrium method was used to test the receivers’ heat-loss. The receivers with increasing emittance were tested to study the variation of heat-loss. Meanwhile, the variable vacuum pressure in the annulus that affects the efficiency of the system was investigated. The influence of vacuumizing rate and getters on the vacuum pressure and heat-loss were discussed. The result shows that the emittance and vacuum pressure affect the receiver's heat-loss dramatically, and the emittance is the major influence factor on the thermal properties. The receiver with 0.08 emittance and 10−3 Pa vacuum pressure has a satisfactory heat-loss of 215.6 W/m at 400 °C. The analysis further reveals that the synergistic effect of both emittance and vacuum pressure on the heat-loss can be reflected by the packaging temperature of the glass tube, and a fitting formula has been established to estimate the receivers’ heat-loss according to the packaging temperature of the glass tube.

  19. ACS production: optimal design of solar thermal power plants; Produccion de ACS. Optimizacion del dimensionado de instalaciones de energia solar termica

    Energy Technology Data Exchange (ETDEWEB)

    Platon Arias, L.; San Jose Alonso, F.

    2009-07-01

    The aim of this project is to develop a program to size solar thermal power plants for the production of the company ACS, which enable optimum value calculations of the different influence parameters (surface, inclination, orientation, energy input) advising diverse circumstances and requirements. The energy input calculation has been effected according to f-chart method. For the solar radiation on inclined and oriented surfaces calculation, has been applied the Klein Method. (Author) 14 refs.

  20. Thermal Characteristics of Multilayer Insulation Materials for Flexible Thin-Film Solar Cell Array of Stratospheric Airship

    Directory of Open Access Journals (Sweden)

    Kangwen Sun

    2014-01-01

    Full Text Available Flexible thin-film solar cell is an efficient energy system on the surface of stratospheric airship for utilizing the solar energy. In order to ensure the normal operation of airship platform, the thermal control problem between the flexible thin-film solar cell and the airship envelope should be properly resolved. In this paper, a multilayer insulation material (MLI is developed first, and low temperature environment test is carried out to verify the insulation effect of MLI. Then, a thermal heat transfer model of flexible thin-film solar cell and MLI is proposed, and the equivalent thermal conductivity coefficients of flexible thin-film solar cell and Nomex honeycomb are calculated based on the environment test and the temperature profile of flexible thin-film solar cell versus each layer of MLI. Finally, FLUENT is used for modeling and simulation analysis on the flexible thin-film solar cell and MLI, and the simulation results agree well with the experimental data, which validate the correctness of the proposed heat transfer model of MLI. In some way, our study can provide helpful support for further engineering applications of flexible thin-film solar cell.

  1. Analysis of the Thermal Stress for Combined Electrode of Soldered Crystalline Silicon Solar Cells under Temperature Field

    Directory of Open Access Journals (Sweden)

    He Wang

    2016-01-01

    Full Text Available Based on the theory of material mechanics and thermal stress analysis, the stress distribution of combined electrode for crystalline silicon solar module was studied for the first time. The shear stress and normal stress distribution of soldered structure for crystalline silicon solar cells under the thermal field were discussed. And the results show that the stress distribution is not simply linear relationship as some results found. But there is a stress concentration at the edge, which was considered as the true reason that caused microcracks at the edge of soldered solar cells. The conclusions we got in this paper provide a theoretical basis for deceasing the breakage rates of soldered crystalline silicon solar cells and improving the reliability of crystalline silicon solar modules.

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

    Science.gov (United States)

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

    1990-01-01

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

  3. Characteristics of thermally reduced graphene oxide and applied for dye-sensitized solar cell counter electrode

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Ching-Yuan, E-mail: cyho@cycu.edu.tw [Department of Mechanical Engineering, Chung Yuan Christian University, Chung-Li, Taiwan (China); Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung Yuan Christian University, Chung-Li, Taiwan (China); Wang, Hong-Wen [Department of Chemistry, Center for Nanotechnology and Institute of Biomedical Technology, Chung Yuan Christian University, Chung-Li, Taiwan (China); Department of Chemistry, Chung Yuan Christian University, Chung-Li, Taiwan (China)

    2015-12-01

    Graphical abstract: Experimental process: (1) graphite oxidized to graphene oxide; (2) thermal reduction from graphene oxide to graphene; (3) applying to DSSC counter electrode. - Highlights: • Intercalated defects were eliminated by increasing reduction temperature of GO. • High reduction temperature of tGP has lower resistance, high the electron lifetime. • Higher thermal reduction of GO proposes electrocatalytic properties. • DSSC using tGP{sub 250} as counter electrode has energy conversion efficiency of 3.4%. - Abstract: Graphene oxide (GO) was synthesized from a flake-type of graphite powder, which was then reduced to a few layers of graphene sheets using the thermal reduction method. The surface morphology, phase crystallization, and defect states of the reduced graphene were determined from an electron microscope equipped with an energy dispersion spectrometer, X-ray diffraction, Raman spectroscopy, and infrared spectra. After graphene formation, the intercalated defects that existed in the GO were removed, and it became crystalline by observing impurity changes and d-spacing. Dye-sensitized solar cells, using reduced graphene as the counter electrode, were fabricated to evaluate the electrolyte activity and charge transport performance. The electrochemical impedance spectra showed that increasing the thermal reduction temperature could achieve faster electron transport and longer electron lifetime, and result in an energy conversion efficiency of approximately 3.4%. Compared to the Pt counter electrode, the low cost of the thermal reduction method suggests that graphene will enjoy a wide range of potential applications in the field of electronic devices.

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

    Science.gov (United States)

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

    1987-01-01

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

  5. Thermal conductivities study of new types of compound adsorbents used in solar adsorption refrigeration

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Huizhong [College of Urban Construction and Environment Engineering, University of Shanghai for Science and Technology, Shanghai 200093 (China)], E-mail: zhz@usst.edu.cn; Zhang Min [College of Food Science Technology, Shanghai Ocean University, Shanghai 200090 (China); Lv Jing; Yu Guoqing; Zou Zhijun [College of Urban Construction and Environment Engineering, University of Shanghai for Science and Technology, Shanghai 200093 (China)

    2009-05-15

    In this paper, the thermal probe is firstly introduced and used in adsorption refrigeration to measure the working pair's thermal conductivities. Different types of compound adsorbents were prepared, and the thermal conductivities of all the types were measured with different adsorption capacities. Experimental results demonstrate that: with the same adsorption capacity, the conductivities of the compound adsorbents increase with the quantity of sodium silicate (Na{sub 2}SiO{sub 3}) content. The conductivities of the compound adsorbents increase sharply when the sodium silicate content is between 0% and 7.5% and increase slowly when the content is 7.5-20%. For 13x zeolite and compound adsorbents Z3 and Z4, their thermal conductivities increase as a quadratic polynomial with their adsorption capacities. The conductivities increase more than 158.2% when the adsorption capacities increase from 0% to 25%. The thermal conductivities of compound adsorbent Z3 and Z4 are 0.183 and 0.199 W (m K){sup -1}, respectively, and increase about 65.4% and 80.1%, respectively, compared with the 13x zeolite. With these test results, the compound adsorbent Z4 is used for making an adsorption bed, and the experimental coefficient of performance (COP) of the solar cooling tube is about 0.26.

  6. Design, simulation and optimization of a solar dish collector with spiral-coil thermal absorber

    Directory of Open Access Journals (Sweden)

    Pavlović Saša R.

    2016-01-01

    Full Text Available The efficient conversion of solar radiation into heat at high temperature levels requires the use of concentrating solar collectors. The goal of this paper is to present the optical and the thermal analysis of a parabolic dish concentrator with a spiral coil receiver. The parabolic dish reflector consists of 11 curvilinear trapezoidal reflective petals constructed by PMMA with silvered mirror layer and has a diameter of 3.8 m, while its focal distance is 2.26m. This collector is designed with commercial software SolidWorks and simulated, optically and thermally in its Flow Simulation Studio. The optical analysis proved that the ideal position of the absorber is at 2.1m from the reflector in order to maximize the optical efficiency and to create a relative uniform heat flux over the absorber. In thermal part of the analysis, the energetic efficiency was calculated approximately 65%, while the exergetic efficiency is varied from 4% to 15% according to the water inlet temperature. Moreover, other important parameters as the heat flux and temperature distribution over the absorber are presented. The pressure drop of the absorber coil is calculated at 0.07bar, an acceptable value.

  7. Thermal Treatment of Mercury Mine Wastes Using a Rotary Solar Kiln

    Directory of Open Access Journals (Sweden)

    Andrés Navarro

    2014-01-01

    Full Text Available Thermal desorption, by a rotary kiln of mercury contaminated soil and mine wastes, has been used in order to volatilize mercury from the contaminated medium. Solar thermal desorption is an innovative treatment that uses solar energy to increase the volatility of contaminants, which are removed from a solid matrix by a controlled air flow system. Samples of soils and mine wastes used in the experiments were collected in the abandoned Valle del Azogue mine (SE, Spain, where a complex ore, composed mainly of cinnabar, arsenic minerals (realgar and orpiment and stibnite, was mined. The results showed that thermal treatment at temperatures >400 °C successfully lowered the Hg content (2070–116 ppm to <15 mg kg−1. The lowest values of mercury in treated samples were obtained at a higher temperature and exposition time. The samples that showed a high removal efficiency (>99% were associated with the presence of significant contents of cinnabar and an equivalent diameter above 0.8 mm.

  8. Experimental analysis of thermal performance according to heat pipe working fluids for evacuated tube solar collector

    Science.gov (United States)

    Joo, Hong-Jin; Kwak, Hee-Youl

    2017-11-01

    The purpose of this study was to experimentally investigate the thermal performance and operating characteristics of various heat pipe working fluids in evacuated tube solar collectors. Heat pipe efficiency was evaluated by calculating the solar collector efficiency value when using four types of working fluids: water, ethanol, flutec-pp9 and methyl acetate under the same operating conditions on an indoor experiment apparatus. The experimental conditions were as follows: The inclination angle of the evacuated tube solar collectors were 20°, 40° and 60° from the normal basis. The mass flow rate into the manifold of the evacuated tubular solar collector was 0.3 kg/min. The heat flux on the collector surface was 870 W/m2. The results showed that, at an angle of incidence of 40°, the values of {F}R ( {τ α } ) and {F}R {U}L with methyl acetate as the working fluid were 0.6572 and -2.0086, respectively, with water they were 0.6636 and -1.8457, respectively, ethanol they were 0.6147 and -0.6353, respectively, and with flutec-pp9 they were 0.525, and -3.2313, respectively.

  9. Optical modeling of a solar dish thermal concentrator based on square flat facets

    Directory of Open Access Journals (Sweden)

    Pavlović Saša R.

    2014-01-01

    Full Text Available Solar energy may be practically utilized directly through transformation into heat, electrical or chemical energy. We present a procedure to design a square facet concentrator for laboratory-scale research on medium-temperature thermal processes. The efficient conversion of solar radiation into heat at these temperature levels requires the use of concentrating solar collectors. Large concentrating dishes generally have a reflecting surface made up of a number of individual mirror panels (facets. Optical ray tracing is used to generate a system performance model. A square facet parabolic solar concentrator with realistic specularly surface and facet positioning accuracy will deliver up to 13.604 kW of radiative power over a 250 mm radius disk (receiver diameter located in the focal plane on the focal length of 1500mmwith average concentrating ratio exceeding 1200. The Monte Carlo ray tracing method is used for analysis of the optical performance of the concentrator and to identify the set of geometric concentrator parameters that allow for flux characteristics suitable for medium and high-temperature applications. [Projekat Ministarstva nauke Republike Srbije, br. III42006: Research and development of energy and environmentally highly effective polygeneration systems based on renewable energy resources

  10. Fast-PPP assessment in European and equatorial region near the solar cycle maximum

    Science.gov (United States)

    Rovira-Garcia, Adria; Juan, José Miguel; Sanz, Jaume

    2014-05-01

    The Fast Precise Point Positioning (Fast-PPP) is a technique to provide quick high-accuracy navigation with ambiguity fixing capability, thanks to an accurate modelling of the ionosphere. Indeed, once the availability of real-time precise satellite orbits and clocks is granted to users, the next challenge is the accuracy of real-time ionospheric corrections. Several steps had been taken by gAGE/UPC to develop such global system for precise navigation. First Wide-Area Real-Time Kinematics (WARTK) feasibility studies enabled precise relative continental navigation using a few tens of reference stations. Later multi-frequency and multi-constellation assessments in different ionospheric scenarios, including maximum solar-cycle conditions, were focussed on user-domain performance. Recently, a mature evolution of the technique consists on a dual service scheme; a global Precise Point Positioning (PPP) service, together with a continental enhancement to shorten convergence. A end to end performance assessment of the Fast-PPP technique is presented in this work, focussed in Europe and in the equatorial region of South East Asia (SEA), both near the solar cycle maximum. The accuracy of the Central Processing Facility (CPF) real-time precise satellite orbits and clocks is respectively, 4 centimetres and 0.2 nanoseconds, in line with the accuracy of the International GNSS Service (IGS) analysis centres. This global PPP service is enhanced by the Fast-PPP by adding the capability of global undifferenced ambiguity fixing thanks to the fractional part of the ambiguities determination. The core of the Fast-PPP is the capability to compute real-time ionospheric determinations with accuracies at the level or better than 1 Total Electron Content Unit (TECU), improving the widely-accepted Global Ionospheric Maps (GIM), with declared accuracies of 2-8 TECU. This large improvement in the modelling accuracy is achieved thanks to a two-layer description of the ionosphere combined with

  11. Computational Analysis of Nanoparticles-Molten Salt Thermal Energy Storage for Concentrated Solar Power Systems

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Vinod [Univ. of Texas, El Paso, TX (United States)

    2017-05-05

    High fidelity computational models of thermocline-based thermal energy storage (TES) were developed. The research goal was to advance the understanding of a single tank nanofludized molten salt based thermocline TES system under various concentration and sizes of the particles suspension. Our objectives were to utilize sensible-heat that operates with least irreversibility by using nanoscale physics. This was achieved by performing computational analysis of several storage designs, analyzing storage efficiency and estimating cost effectiveness for the TES systems under a concentrating solar power (CSP) scheme using molten salt as the storage medium. Since TES is one of the most costly but important components of a CSP plant, an efficient TES system has potential to make the electricity generated from solar technologies cost competitive with conventional sources of electricity.

  12. Carbon dioxide as working fluid for medium and high-temperature concentrated solar thermal systems

    Directory of Open Access Journals (Sweden)

    Van Duong

    2014-03-01

    Full Text Available This paper explores the benefits and drawbacks of using carbon dioxide in solar thermal systems at medium and high operating temperatures. For medium temperatures, application of CO2 in non-imaging-optics based compound parabolic concentrators (CPC combined with evacuated-tube collectors is studied. These collectors have been shown to obtain efficiencies higher than 40% operating at around 200℃ without the need of tracking. Validated numerical models of external compound parabolic concentrators (XCPCs are used to simulate their performance using CO2 as working fluid. For higher temperatures, a mathematical model is implemented to analyze the operating performance of a parabolic trough solar collector (PTC using CO2 at temperatures between 100℃ and 600℃.

  13. The Influence of Different Absorbed Coatings on Thermal Effect of Prefabricated Solar Collector Panels

    Directory of Open Access Journals (Sweden)

    Wang Qi

    2016-01-01

    Full Text Available Prefabricated solar collector panels is a kind of new permeability structure of collector panels. For this test, we adopt a certain proportion of copper oxide, magnesium oxide and iron oxide to enamel paint as absorbed panel coating and make two kinds of collector panels for different forms of color by dark green coating and black coating. By the methods of comparison, the two kinds of panel collector efficiency and heat loss coefficient UL were tested. The results showed that there was a slight difference between the heat loss coefficient of prefabricated solar collector panels, using the panel with dark green coating’s comprehensive thermal effect is well than the panel with black coating. The beautiful appearance color is more suitable for building requirements.

  14. Advanced storage concepts for solar thermal systems in low energy buildings. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Furbo, S.; Andersen, Elsa; Schultz, Joergen M.

    2006-04-07

    The aim of Task 32 is to develop new and advanced heat storage systems which are economic and technical suitable as long-term heat storage systems for solar heating plants with a high degree of coverage. The project is international and Denmark's participation has focused on Subtask A, C, and D. In Subtask A Denmark has contributed to a status report about heat storage systems. In Subtask C Denmark has focused on liquid thermal storage tanks based on NaCH{sub 3}COO?3H{sub 2}O with a melting point of 58 deg. C. Theoretical and experimental tests have been conducted in order to establish optimum conditions for storage design. In Subtask D theoretical and experimental tests of optimum designs for advanced water tanks for solar heating plants for combined space heating and domestic hot water have been conducted. (BA)

  15. Thermally induced structural evolution and performance of mesoporous block copolymer-directed alumina perovskite solar cells.

    KAUST Repository

    Tan, Kwan Wee

    2014-04-11

    Structure control in solution-processed hybrid perovskites is crucial to design and fabricate highly efficient solar cells. Here, we utilize in situ grazing incidence wide-angle X-ray scattering and scanning electron microscopy to investigate the structural evolution and film morphologies of methylammonium lead tri-iodide/chloride (CH3NH3PbI(3-x)Cl(x)) in mesoporous block copolymer derived alumina superstructures during thermal annealing. We show the CH3NH3PbI(3-x)Cl(x) material evolution to be characterized by three distinct structures: a crystalline precursor structure not described previously, a 3D perovskite structure, and a mixture of compounds resulting from degradation. Finally, we demonstrate how understanding the processing parameters provides the foundation needed for optimal perovskite film morphology and coverage, leading to enhanced block copolymer-directed perovskite solar cell performance.

  16. Thermal design of a modern, air-conditioned, single-floor, solar-powered desert house

    KAUST Repository

    Serag-Eldin, M. A.

    2011-12-01

    The paper presents a thermal analysis of a single-floor, solar-powered desert house. The house is air-conditioned and provides all modern comforts and facilities. Electrical power, which drives the entire energy system, is generated by roof-mounted photovoltaic modules. The modules are fixed on special cradles which fold at night to expose the roof to the night sky, thereby enhancing night-time cooling, which is substantial in the desert environment. A detailed dynamic heat transfer analysis is conducted for the building envelope, coupled with a solar radiation model. Application to a typical Middle-Eastern desert site reveals that indeed such a design is feasible with present-day technology; and should be even more attractive with future advances in technology. © 2011 Copyright Taylor and Francis Group, LLC.

  17. Thermally Induced Structural Evolution and Performance of Mesoporous Block Copolymer-Directed Alumina Perovskite Solar Cells

    Science.gov (United States)

    2015-01-01

    Structure control in solution-processed hybrid perovskites is crucial to design and fabricate highly efficient solar cells. Here, we utilize in situ grazing incidence wide-angle X-ray scattering and scanning electron microscopy to investigate the structural evolution and film morphologies of methylammonium lead tri-iodide/chloride (CH3NH3PbI3–xClx) in mesoporous block copolymer derived alumina superstructures during thermal annealing. We show the CH3NH3PbI3–xClx material evolution to be characterized by three distinct structures: a crystalline precursor structure not described previously, a 3D perovskite structure, and a mixture of compounds resulting from degradation. Finally, we demonstrate how understanding the processing parameters provides the foundation needed for optimal perovskite film morphology and coverage, leading to enhanced block copolymer-directed perovskite solar cell performance. PMID:24684494

  18. Study on Thermal Performance Assessment of Solar Hot Water Systems in Malaysia

    Directory of Open Access Journals (Sweden)

    Sulaiman Shaharin Anwar

    2014-07-01

    Full Text Available Solar Hot Water Systems (SHWS are gaining popularity in Malaysia due to increasing cost of electricity and also awareness of environmental issues related to the use of fossil fuels. The introduction of solar hot water systems in Malaysia is an indication that it has potential market. However, there is a need for a proper methodology for rating the energy performance of these systems. The main objective of this study is to assess the thermal performance of several SHWS subject to four different locations in Malaysia using combined direct measurement and computer modelling using the TRNSYS simulation program. The results showed distinct differences in performance of the systems as a result of locations and manufacturers. The findings could be used further in developing an acceptable rating system for SHWS in Malaysia.

  19. Evaluation of annual efficiencies of high temperature central receiver concentrated solar power plants with thermal energy storage.

    Energy Technology Data Exchange (ETDEWEB)

    Ehrhart, Brian David; Gill, David Dennis

    2013-07-01

    The current study has examined four cases of a central receiver concentrated solar power plant with thermal energy storage using the DELSOL and SOLERGY computer codes. The current state-of-the-art base case was compared with a theoretical high temperature case which was based on the scaling of some input parameters and the estimation of other parameters based on performance targets from the Department of Energy SunShot Initiative. This comparison was done for both current and high temperature cases in two configurations: a surround field with an external cylindrical receiver and a north field with a single cavity receiver. There is a fairly dramatic difference between the design point and annual average performance, especially in the solar field and receiver subsystems, and also in energy losses due to the thermal energy storage being full to capacity. Additionally, there are relatively small differences (<2%) in annual average efficiencies between the Base and High Temperature cases, despite an increase in thermal to electric conversion efficiency of over 8%. This is due the increased thermal losses at higher temperature and operational losses due to subsystem start-up and shut-down. Thermal energy storage can mitigate some of these losses by utilizing larger thermal energy storage to ensure that the electric power production system does not need to stop and re-start as often, but solar energy is inherently transient. Economic and cost considerations were not considered here, but will have a significant impact on solar thermal electric power production strategy and sizing.

  20. Thermal Stability-Enhanced and High-Efficiency Planar Perovskite Solar Cells with Interface Passivation.

    Science.gov (United States)

    Zhang, Weihai; Xiong, Juan; Jiang, Li; Wang, Jianying; Mei, Tao; Wang, Xianbao; Gu, Haoshuang; Daoud, Walid A; Li, Jinhua

    2017-11-08

    As the electron transport layer (ETL) of perovskite solar cells, oxide semiconductor zinc oxide (ZnO) has been attracting great attention due to its relatively high mobility, optical transparency, low-temperature fabrication, and good environment stability. However, the nature of ZnO will react with the patron on methylamine, which would deteriorate the performance of cells. Although many methods, including high-temperature annealing, doping, and surface modification, have been studied to improve the efficiency and stability of perovskite solar cells with ZnO ETL, devices remain relatively low in efficiency and stability. Herein, we adopted a novel multistep annealing method to deposit a porous PbI 2 film and improved the quality and uniformity of perovskite films. The cells with ZnO ETL were fabricated at the temperature of <150 °C by solution processing. The power conversion efficiency (PCE) of the device fabricated by the novel annealing method increased from 15.5 to 17.5%. To enhance the thermal stability of CH 3 NH 3 PbI 3 (MAPbI 3 ) on the ZnO surface, a thin layer of small molecule [6,6]-phenyl-C 61 -butyric acid methyl ester (PCBM) was inserted between the ZnO layer and perovskite film. Interestingly, the PCE of PCBM-passivated cells could reach nearly 19.1%. To our best knowledge, this is the highest PCE value of ZnO-based perovskite solar cells until now. More importantly, PCBM modification could effectively suppress the decomposition of MAPbI 3 and improve the thermal stability of cells. Therefore, the ZnO is a promising candidate of electron transport material for perovskite solar cells in future applications.

  1. Assessment Of The Viability Of Kaduna City Climate For Year Round Use Of Direct Solar Thermal Cooking Fuel In Housing

    Directory of Open Access Journals (Sweden)

    Boumann Ephraim Sule

    2017-10-01

    Full Text Available Solar energy obtained from the sun is the world most abundant and cheapest source of energy as a cooking fuel. It comes in two forms Concentrated Solar Thermal direct conversion of solar energy to heat that cooks and Solar Photovoltaic PV a conversion of solar energy to electrical then to heat energy the former technology is simple and far cheaper. Despite all these architectural and engineering researches is yet to capture it for indoor cooking because of inability to cook year round due the claimed hindrances by weather condition such as clouds rainfall wind dusty atmosphere and many others. This paper attempted to look into the possibility of cooking year round in Kaduna city. It collected and analyzed ten years climatic data from three different meteorological stations strategically located round the city this showed a low solar radiation in the month of August. It further compared the result with a literature review of solar cooking carried in the same month the findings showed at the peak of each weather hindrance a another element overrides it to give enough minimum energy for cooking a meals. This paper has therefore pointed the potentials of Kaduna city climate for year round use of concentrated solar thermal as a cooking fuel in residential building and further recommends the architectural collaboration with engineers for the direct capturing of solar rays into residential dwelling as a sustainable cooking fuel.

  2. Conceptual design and analysis of a Dish-Rankine solar thermal power system

    Science.gov (United States)

    Pons, R. L.

    1980-08-01

    A Point Focusing Distributed Receiver (PFDR) solar thermal electric system which employs small Organic Rankine Cycle (ORC) engines is examined with reference to its projected technical/economic performance. With mass-produced power modules (about 100,000 per year), the projected life-cycle energy cost for an optimized no-storage system is estimated at 67 mills/kWh (Levelized Busbar Energy Cost) without the need for advanced development of any of its components. At moderate production rates (about 50 MWe/yr) system energy costs are competitive with conventional power generation systems in special remote-site types of applications.

  3. Storage of low grade solar thermal energy by adsorption of organics

    Science.gov (United States)

    Kohler, Tobias; Müller, Karsten

    2017-06-01

    In this work the efficiency of new systems for adsorptive energy storage for low grade solar thermal energy is evaluated. They are based on different adsorption systems with alcohols as adsorbates on activated carbon as adsorbent. They showed superior storage characteristics compared to the reference working pair water / zeolite 13X. The maximum efficiencies of the systems methanol and ethanol on activated carbon lie in the same range as the efficiency of the reference pair, but are reached at lower regeneration temperatures. Therefore, these systems are perfectly suited for the storage of low grad heat from collector types like the flat-plate collector or vacuum-collectors.

  4. Soil moisture estimation using reflected solar and emitted thermal infrared radiation

    Science.gov (United States)

    Jackson, R. D.; Cihlar, J.; Estes, J. E.; Heilman, J. L.; Kahle, A.; Kanemasu, E. T.; Millard, J.; Price, J. C.; Wiegand, C. L.

    1978-01-01

    Classical methods of measuring soil moisture such as gravimetric sampling and the use of neutron moisture probes are useful for cases where a point measurement is sufficient to approximate the water content of a small surrounding area. However, there is an increasing need for rapid and repetitive estimations of soil moisture over large areas. Remote sensing techniques potentially have the capability of meeting this need. The use of reflected-solar and emitted thermal-infrared radiation, measured remotely, to estimate soil moisture is examined.

  5. Study on effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans

    OpenAIRE

    Dina, Sari Farah; Ambarita, Himsar; Farel H. Napitupulu; Kawai, Hideki

    2015-01-01

    The main objective is to assess effectiveness of continuous solar dryer integrated with desiccant thermal storage for drying cocoa beans. Two type of desiccants were tested, molecular sieve 13× (Na86 [(AlO2)86·(SiO2)106]·264H2O) as an adsorbent type and CaCl2 as an absorbent type. The results revealed that during sunshine hours, the maximum temperature within the drying chamber varied from 40 °C to 54 °C. In average, it was 9–12 °C higher than ambient temperature. These temperatures are very ...

  6. Expanding thermal plasma chemical vapour deposition of ZnO:Al layers for CIGS solar cells

    OpenAIRE

    Sharma, K; Williams, B. L.; Mittal, A.; Knoops, H. C. M.; Kniknie, B.J.; Bakker, N J; Kessels, W. M. M.; Schropp, R.E.I.; Creatore, M.

    2014-01-01

    Aluminium-doped zinc oxide (ZnO:Al) grown by expanding thermal plasma chemical vapour deposition (ETP-CVD) has demonstrated excellent electrical and optical properties, which make it an attractive candidate as a transparent conductive oxide for photovoltaic applications. However, when depositing ZnO:Al on CIGS solar cell stacks, one should be aware that high substrate temperature processing (i.e., >200°C) can damage the crucial underlying layers/interfaces (such as CIGS/CdS and CdS/i-ZnO). In...

  7. Potential impact of ZT = 4 thermoelectric materials on solar thermal energy conversion technologies.

    Science.gov (United States)

    Xie, Ming; Gruen, Dieter M

    2010-11-18

    State-of-the-art methodologies for the conversion of solar thermal power to electricity are based on conventional electromagnetic induction techniques. If appropriate ZT = 4 thermoelectric materials were available, it is likely that conversion efficiencies of 30-40% could be achieved. The availability of all solid state electricity generation would be a long awaited development in part because of the elimination of moving parts. This paper presents a preliminary examination of the potential performance of ZT = 4 power generators in comparison with Stirling engines taking into account specific mass, volume and cost as well as system reliability. High-performance thermoelectrics appear to have distinct advantages over magnetic induction technologies.

  8. An experimental investigation of performance of a double pass solar air heater with thermal storage medium

    Directory of Open Access Journals (Sweden)

    Ali Hafiz Muhammad

    2015-01-01

    Full Text Available The performance of a double pass solar air heater was experimentally investigated using four different configurations. First configuration contained only absorber plate whereas copper tubes filled with thermal storage medium (paraffin wax were added on the absorber plate in the second configuration. Aluminum and steel rods as thermal enhancer were inserted in the middle of paraffin wax of each tube for configurations three and four respectively. Second configuration provided useful heat for about 1.5 hours after the sunset compared to first configuration. Configurations three and four provided useful heat for about 2 hours after the sunset. The maximum efficiency of about 96% was achieved using configuration three (i.e. using Aluminum rods in the middle of copper tubes filled with paraffin wax.

  9. A Selective Metasurface Absorber with An Amorphous Carbon Interlayer for Solar Thermal Applications

    CERN Document Server

    Wan, Chenglong; Nunez-Sanchez, S; Chen, Lifeng; Lopez-Garcia, M; Pugh, J; Zhu, Bofeng; Selvaraj, P; Mallick, T; Senthilarasu, S; Cryan, M J

    2016-01-01

    This paper presents fabrication, measurement and modelling results for a metal-dielectric-metal metasurface absorber for solar thermal applications. The structure uses amorphous carbon as an inter-layer between thin gold films with the upper film patterned with a 2D periodic array using focused ion beam etching. The patterned has been optimised to give high absorptance from 400-1200nm and low absorptance above this wavelength range to minimise thermal radiation and hence obtain higher temperature performance. Wide angle absorptance results are shown and detailed modelling of a realistic nanostructured upper layer results in excellent agreement between measured and modelled results. The use of gold in this paper is a first step towards a high temperature metasurface where gold can be replaced by other refractory metals such as tungsten or chrome.

  10. Solar Simulation for the CREST Preflight Thermal-Vacuum Test at B-2

    Science.gov (United States)

    Ziemke, Robert A.

    2013-01-01

    In June 2011, the multi-university sponsored Cosmic Ray Electron Synchrotron Telescope (CREST) has undergone thermal-vacuum qualification testing at the NASA Glenn Research Center (GRC), Plum Brook Station, Sandusky, Ohio. The testing was performed in the B- 2 Space Propulsion Facility vacuum chamber. The CREST was later flown over the Antarctic region as the payload of a stratospheric balloon. Solar simulation was provided by a system of planar infrared lamp arrays specifically designed for CREST. The lamp arrays, in conjunction with a liquid-nitrogen-cooled cryoshroud, achieved the required thermal conditions for the qualification tests. This report focuses on the design and analysis of the planar arrays based on first principles. Computational spreadsheets are included in the report.

  11. Thermal asymmetry model of single slope single basin solar still with sponge liner

    Directory of Open Access Journals (Sweden)

    Shanmugan Sengottain

    2014-01-01

    Full Text Available An attempt has been made to propose a thermal asymmetry model for single slope basin type solar still with sponge liner of different thickness (3cm, 5cm, and 10cm in the basin. Two different color sponge liners have been used i.e., yellow and black. In the proposed design, a suitable dripping arrangement has been designed and used to pour water drop by drop over the sponge liner instead of sponge liner in stagnant saline water in the basin. The special arrangement overcomes the dryness of the sponge during peak sunny hours. The performance of the system with black color sponge of 3cm thickness shows better result with an output of 5.3 kg/m2 day and the proposed model have used to find the thermal asymmetries during the working hours of the still.

  12. Effect of Regenerative Organic Rankine Cycle (RORC on the Performance of Solar Thermal Power in Yogyakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Ghalya Pikra

    2013-07-01

    Full Text Available This paper presents effect of Regenerative Organic Rankine Cycle (RORC on the performance of solar thermal power in Yogyakarta, Indonesia. Solar thermal power is a plant that uses solar energy as heat source. Indonesia has high humidity level, so that parabolic trough is the most suitable type of solar thermal power technology to be developed, where the design is made with small focal distance. Organic Rankine Cycle (ORC is a Rankine cycle that use organic fluid as working fluid to utilize low temperature heat sources. RORC is used to increase ORC performance. The analysis was done by comparing ORC system with and without regenerator addition. Refrigerant that be used in the analysis is R123. Preliminary data was taken from the solar collector system that has been installed in Yogyakarta. The analysis shows that with 36 m total parabolic length, the resulting solar collector capacity is 63 kW, heat input/evaporator capacity is determined 26.78 kW and turbine power is 3.11 kW for ORC, and 3.38 kW for RORC. ORC thermal efficiency is 11.28% and RORC is 12.26%. Overall electricity efficiency is 4.93% for ORC, and 5.36% for RORC. With 40°C condensing temperature and evaporation at 10 bar saturated condition, efficiency of RORC is higher than ORC. Greater evaporation temperature at the same pressure (10 bar provide greater turbine power and efficiency.

  13. Comparative Ab-Initio Study of Substituted Norbornadiene-Quadricyclane Compounds for Solar Thermal Storage.

    Science.gov (United States)

    Kuisma, Mikael J; Lundin, Angelica M; Moth-Poulsen, Kasper; Hyldgaard, Per; Erhart, Paul

    2016-02-25

    Molecular photoswitches that are capable of storing solar energy, so-called molecular solar thermal storage systems, are interesting candidates for future renewable energy applications. In this context, substituted norbornadiene-quadricyclane systems have received renewed interest due to recent advances in their synthesis. The optical, thermodynamic, and kinetic properties of these systems can vary dramatically depending on the chosen substituents. The molecular design of optimal compounds therefore requires a detailed understanding of the effect of individual substituents as well as their interplay. Here, we model absorption spectra, potential energy storage, and thermal barriers for back-conversion of several substituted systems using both single-reference (density functional theory using PBE, B3LYP, CAM-B3LYP, M06, M06-2x, and M06-L functionals as well as MP2 calculations) and multireference methods (complete active space techniques). Already the diaryl substituted compound displays a strong red-shift compared to the unsubstituted system, which is shown to result from the extension of the conjugated π-system upon substitution. Using specific donor/acceptor groups gives rise to a further albeit relatively smaller red-shift. The calculated storage energy is found to be rather insensitive to the specific substituents, although solvent effects are likely to be important and require further study. The barrier for thermal back-conversion exhibits strong multireference character and as a result is noticeably correlated with the red-shift. Two possible reaction paths for the thermal back-conversion of diaryl substituted quadricyclane are identified and it is shown that among the compounds considered the path via the acceptor side is systematically favored. Finally, the present study establishes the basis for high-throughput screening of norbornadiene-quadricyclane compounds as it provides guidelines for the level of accuracy that can be expected for key properties from

  14. Design of Particle-Based Thermal Energy Storage for a Concentrating Solar Power System

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Zhiwen [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhang, Ruichong [Colorado School of Mines; Sawaged, Fadi [Colorado School of Mines

    2017-06-03

    Solid particles can operate at higher temperature than current molten salt or oil, and they can be a heat-transfer and storage medium in a concentrating solar power (CSP) system. By using inexpensive solid particles and containment material for thermal energy storage (TES), the particle-TES cost can be significantly lower than other TES methods such as a nitrate-salt system. The particle-TES system can hold hot particles at more than 800 degrees C with high thermal performance. The high particle temperatures increase the temperature difference between the hot and cold particles, and they improve the TES capacity. The particle-based CSP system is able to support high-efficiency power generation, such as the supercritical carbon-dioxide Brayton power cycle, to achieve >50% thermal-electric conversion efficiency. This paper describes a solid particle-TES system that integrates into a CSP plant. The hot particles discharge to a heat exchanger to drive the power cycle. The returning cold particles circulate through a particle receiver to absorb solar heat and charge the TES. This paper shows the design of a particle-TES system including containment silos, foundation, silo insulation, and particle materials. The analysis provides results for four TES capacities and two silo configurations. The design analysis indicates that the system can achieve high thermal efficiency, storage effectiveness (i.e., percentage usage of the hot particles), and exergetic efficiency. An insulation method for the hot silo was considered. The particle-TES system can achieve high performance and low cost, and it holds potential for next-generation CSP technology.

  15. Location Study of Solar Thermal Power Plant in the State of Pernambuco Using Geoprocessing Technologies and Multiple-Criteria Analysis

    Directory of Open Access Journals (Sweden)

    Verônica Wilma B. Azevêdo

    2017-07-01

    Full Text Available Solar Thermal Technology for the generation of electricity in large scale has been a reality in the world since the 1980s, when the first large-sized solar plants in the United States were introduced. Brazil presents great potential for the development of large-scale projects, although it is noted that the main barriers for the insertion of this technology in Brazilian market are the lack of incentives and goals and associated costs. In a way to contribute to the insertion of solar thermal technology in Brazil, this paper presents a macro-spatial approach, based on the use of Multiple-Criteria Decision Analysis and Geoprocessing, for the location of solar thermal power plants. The applied methodology for Pernambuco, located in the Northeast Region of Brazil, considered the implantation of parabolic trough solar power plant of 80 MW, operating only in solar mode, without heat storage. Based on performed analysis, it was confirmed that Pernambuco presents great potential for the installation of solar power plants, especially in the backlands of Pernambuco. Performed validations in the model demonstrate that the methodology attended the objective once the consistence between the assigned weights to the thematic layers, individually, and the final Map of site suitability were evidenced.

  16. Standard Practice for Solar Simulation for Thermal Balance Testing of Spacecraft

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1973-01-01

    1.1 Purpose: 1.1.1 The primary purpose of this practice is to provide guidance for making adequate thermal balance tests of spacecraft and components where solar simulation has been determined to be the applicable method. Careful adherence to this practice should ensure the adequate simulation of the radiation environment of space for thermal tests of space vehicles. 1.1.2 A corollary purpose is to provide the proper test environment for systems-integration tests of space vehicles. An accurate space-simulation test for thermal balance generally will provide a good environment for operating all electrical and mechanical systems in their various mission modes to determine interferences within the complete system. Although adherence to this practice will provide the correct thermal environment for this type of test, there is no discussion of the extensive electronic equipment and procedures required to support systems-integration testing. 1.2 Nonapplicability—This practice does not apply to or provide inco...

  17. Thermal solar power. New Schemes of Principle. Multifamily facilities and his problems; Energia solar termica. Instalaciones multifamiliares y su problematica. Nuevos esquemas de principio

    Energy Technology Data Exchange (ETDEWEB)

    Acedo, M. A.

    2008-07-01

    Article checks the production of warm sanitary water no-central facilities for thermal solar power of low temperature in the multifamily buildings. In order that the governmental incentives are destined only to the objectively well facilities, also some technical problems are checked. (Author)

  18. New materials for thermal energy storage in concentrated solar power plants

    Science.gov (United States)

    Guerreiro, Luis; Collares-Pereira, Manuel

    2016-05-01

    Solar Thermal Electricity (STE) is an important alternative to PV electricity production, not only because it is getting more cost competitive with the continuous growth in installed capacity, engineering and associated innovations, but also, because of its unique dispatch ability advantage as a result of the already well established 2-tank energy storage using molten salts (MS). In recent years, research has been performed, on direct MS systems, to which features like modularity and combinations with other (solid) thermal storage materials are considered with the goal of achieving lower investment cost. Several alternative materials and systems have been studied. In this research, storage materials were identified with thermo-physical data being presented for different rocks (e.g. quartzite), super concrete, and other appropriate solid materials. Among the new materials being proposed like rocks from old quarries, an interesting option is the incorporation of solid waste material from old mines belonging to the Iberian Pyritic Belt. These are currently handled as byproducts of past mine activity, and can potentially constitute an environmental hazard due to their chemical (metal) content. This paper presents these materials, as part of a broad study to improve the current concept of solar energy storage for STE plants, and additionally presents a potentially valuable solution for environmental protection related to re-use of mining waste.

  19. Solar heat pipe testing of the Stirling thermal motors 4-120 Stirling engine

    Energy Technology Data Exchange (ETDEWEB)

    Andraka, C.E.; Rawlinson, K.S.; Moss, T.A.; Adkins, D.R.; Moreno, J.B.; Gallup, D.R.; Cordeiro, P.G. [Sandia National Labs., Albuquerque, NM (United States); Johansson, S. [Stirling Thermal Motors, Inc., Ann Arbor, MI (United States)

    1996-07-01

    Stirling-cycle engines have been identified as a promising technology for the conversion of concentrated solar energy into usable electrical power. A 25kW electric system takes advantage of existing Stirling-cycle engines and existing parabolic concentrator designs. In previous work, the concentrated sunlight impinged directly on the heater head tubes of the Stirling Thermal Motors (STM) 4-120 engine. A Sandia-designed felt-metal-wick heat pipe receiver was fitted to the STM 4-120 engine for on-sun testing on Sandia`s Test Bed Solar Concentrator. The heat pipe uses sodium metal as an intermediate two-phase heat transfer fluid. The receiver replaces the directly-illuminated heater head previously tested. The heat pipe receiver provides heat isothermally to the engine, and the heater head tube length is reduced, both resulting in improved engine performance. The receiver also has less thermal losses than the tube receiver. The heat pipe receiver design is based on Sandia`s second-generation felt-wick heat pipe receiver. This paper presents the interface design, and compares the heat pipe/engine test results to those of the directly-illuminated receiver/engine package.

  20. The small community solar thermal power experiment. Parabolic dish technology for industrial process heat application

    Science.gov (United States)

    Polzien, R. E.; Rodriguez, D.

    1981-01-01

    Aspects of incorporating a thermal energy transport system (ETS) into a field of parabolic dish collectors for industrial process heat (IPH) applications were investigated. Specific objectives are to: (1) verify the mathematical optimization of pipe diameters and insulation thicknesses calculated by a computer code; (2) verify the cost model for pipe network costs using conventional pipe network construction; (3) develop a design and the associated production costs for incorporating risers and downcomers on a low cost concentrator (LCC); (4) investigate the cost reduction of using unconventional pipe construction technology. The pipe network design and costs for a particular IPH application, specifically solar thermally enhanced oil recovery (STEOR) are analyzed. The application involves the hybrid operation of a solar powered steam generator in conjunction with a steam generator using fossil fuels to generate STEOR steam for wells. It is concluded that the STEOR application provides a baseline pipe network geometry used for optimization studies of pipe diameter and insulation thickness, and for development of comparative cost data, and operating parameters for the design of riser/downcomer modifications to the low cost concentrator.

  1. Evaluation of thermal and photovoltaic solar systems in agricultural production units, Northern Huetar Region, Costa Rica

    Directory of Open Access Journals (Sweden)

    Tomás de Jesús Guzmán Hernández

    2017-09-01

    Full Text Available The dependence on fossil fuels urges society to seek for clean energy alternatives, in order to mitigate the effects of climate change. The objective of this study was to determine the potential of solar energy used for water heating and electricity generation. The study was conducted at the dairy of the Technology Institute of Costa Rica, San Carlos Headquarter, from May 15 to April 2016. The data related to the amount of the electricity produced and the temperature reached by water was obtained from the installed photovoltaic and thermal systems, the data was recorded by a computerized register. The obtained information about electricity production allowed researchers to calculate the amount of carbon dioxide equivalent that was not emitted into the atmosphere, and also the acquired economic saving on consumption. The use of these systems allowed the production unit have a self- sufficient source of electrical energy percentage, actually around 30 to 40% of the total electrical consumption. According to the energy production, the solar thermal system was capable to increase water temperature between 20 to 37 °C, temperature that represents more than 70% of the energy needed in order to reach the required water temperature (70 °C for cleaning and sanitizing the milking equipment, and also an economical saving around $90 per month was achieved. The results showed that these systems allow to improve the economical and productive efficiency of agricultural production units in the Northern Huetar Region of Costa Rica.

  2. III-Nitride Membranes for Thermal Bio-Sensing and Solar Hydrogen Generation

    KAUST Repository

    Elafandy, Rami Tarek Mahmoud

    2017-09-01

    III-nitride nanostructures have generated tremendous scientific and technological interests in studying and engineering their low dimensional physics phenomena. Among these, 2D planar, free standing III-nitride nanomembranes are unrivalled in their scalability for high yield manufacture and can be mechanically manipulated. Due to the increase in their surface to volume ratio and the manifestation of quantum phenomena, these nanomembranes acquire unique physical properties. Furthermore, III-nitride membranes are chemically stable and biocompatible. Finally, nanomembranes are highly flexible and can follow curvilinear surfaces present in biological systems. However, being free-standing, requires especially new techniques for handling nanometers or micrometers thick membrane devices. Furthermore, effectively transferring these membrane devices to other substrates is not a direct process which requires the use of photoresists, solvents and/or elastomers. Finally, as the membranes are transferred, they need to be properly attached for subsequent device fabrications, which often includes spin coating and rinsing steps. These engineering complications have impeded the development of novel devices based on III-nitride membranes. In this thesis, we demonstrate the versatility of III-nitride membranes where we develop a thermal bio-sensor nanomembrane and solar energy photo-anode membrane. First, we present a novel preparation technique of nanomembranes with new characteristics; having no threading dislocation cores. We then perform optical characterization to reveal changes in their defect densities compared to the bulk crystal. We also study their mechanical properties where we successfully modulate their bandgap emission by 55 meV through various external compressive and tensile strain fields. Furthermore, we characterize the effect of phonon-boundary scattering on their thermal properties where we report a reduction of thermal conductivity from 130 to 9 W/mK. We employ

  3. The Cost-Optimal Distribution of Wind and Solar Generation Facilities in a Simplified Highly Renewable European Power System

    Science.gov (United States)

    Kies, Alexander; von Bremen, Lüder; Schyska, Bruno; Chattopadhyay, Kabitri; Lorenz, Elke; Heinemann, Detlev

    2016-04-01

    The transition of the European power system from fossil generation towards renewable sources is driven by different reasons like decarbonisation and sustainability. Renewable power sources like wind and solar have, due to their weather dependency, fluctuating feed-in profiles, which make their system integration a difficult task. To overcome this issue, several solutions have been investigated in the past like the optimal mix of wind and PV [1], the extension of the transmission grid or storages [2]. In this work, the optimal distribution of wind turbines and solar modules in Europe is investigated. For this purpose, feed-in data with an hourly temporal resolution and a spatial resolution of 7 km covering Europe for the renewable sources wind, photovoltaics and hydro was used. Together with historical load data and a transmission model , a simplified pan-European power power system was simulated. Under cost assumptions of [3] the levelized cost of electricity (LCOE) for this simplified system consisting of generation, consumption, transmission and backup units is calculated. With respect to the LCOE, the optimal distribution of generation facilities in Europe is derived. It is shown, that by optimal placement of renewable generation facilities the LCOE can be reduced by more than 10% compared to a meta study scenario [4] and a self-sufficient scenario (every country produces on average as much from renewable sources as it consumes). This is mainly caused by a shift of generation facilities towards highly suitable locations, reduced backup and increased transmission need. The results of the optimization will be shown and implications for the extension of renewable shares in the European power mix will be discussed. The work is part of the RESTORE 2050 project (Wuppertal Institute, Next Energy, University of Oldenburg), that is financed by the Federal Ministry of Education and Research (BMBF, Fkz. 03SFF0439A). [1] Kies, A. et al.: Kies, Alexander, et al

  4. Covalent functionalization of graphene by azobenzene with molecular hydrogen bonds for long-term solar thermal storage

    OpenAIRE

    Feng, Yiyu; Liu, Hongpo; Luo, Wen; Liu, Enzuo; Zhao, Naiqin; Yoshino, Katsumi; Feng, Wei

    2013-01-01

    Reduced graphene oxide-azobenzene (RGO-AZO) hybrids were prepared via covalent functionalization for long-term solar thermal storage. Thermal barrier (?Ea ) of cis to tran reversion and thermal storage (?H) were improved by molecular hydrogen bonds (H-bonds) through ortho- or para-substitution of AZO. Intramolecular H-bonds thermally stabilized cis-ortho-AZO on RGO with a long-term half-life of 5400?h (?Ea = 1.2?eV), which was much longer than that of RGO-para-AZO (116?h). RGO-para-AZO with o...

  5. Solar thermal production of zinc - Final steps toward scale-up - Final report

    Energy Technology Data Exchange (ETDEWEB)

    Meier, A.

    2008-05-15

    A 10 kW receiver-reactor prototype (called ZIRRUS) was further improved and tested for the solar thermal de-composition of ZnO, which is the 1{sup st} step of the two-step water-splitting thermochemical ZnO/Zn cycle. The rotating cylindrical cavity was made of either sintered ZnO or sintered Al{sub 2}O{sub 3} tiles placed on top of a multi-layer Al{sub 2}O{sub 3}-SiO{sub 2}-Y{sub 2}O{sub 3}-based ceramics for thermal shock resistance, mechanical stability, gas diffusion barrier, and thermal insulation. Pre-heated Ar gas was injected for aerodynamic window protection and for minimizing recombination of product gases in the cavity. Experimentation was carried out at PSI's High-Flux Solar Simulator with the direct heating 10 kW reactor prototype subjected to peak radiative fluxes exceeding 5,800 suns. The reactor operated without incident for a total of more than 40 h at maximum temperatures - measured behind the ZnO and Al{sub 2}O{sub 3} tiles - ranging from 1807-1907 K. Thermal dissociation of ZnO(s) near 2000 K was demonstrated for experimental runs over 4 h in transient ablation mode with up to nine semi-continuous feed cycles of ZnO particles. A working Zn/O{sub 2} separation device based on the rapid quenching of the Zn/O{sub 2} mixture is ready to be incorporated at the exit of the solar reactor. Zinc yields of up to 94% were obtained when using total Ar/Zn(g) dilution of 530 and a cooling rate of about 10{sup 5} K/s. The fully integrated solar reactor will be scaled up to the pilot scale of 100 kW. A newly developed reactor model that couples radiation, conduction, and convection heat transfer to the reaction kinetics will allow determining optimal operational conditions for matching the feeding rate to the reaction rate and for maximizing solar-to-chemical energy conversion efficiency. The 2{sup nd} step of the ZnO/Zn cycle has been experimentally demonstrated at ETH using an aerosol-flow reactor for in-situ formation and hydrolysis of Zn nanoparticles

  6. Methods for Analyzing the Economic Value of Concentrating Solar Power with Thermal Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Miller, Mackay [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhou, Ella [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Caixia [State Grid Energy Research Inst., Beijing (China)

    2015-07-20

    Concentrating solar power with thermal energy storage (CSP-TES) provides multiple quantifiable benefits compared to CSP without storage or to solar photovoltaic (PV) technology, including higher energy value, ancillary services value, and capacity value. This report describes modeling approaches to quantifying these benefits that have emerged through state-level policymaking in the United States as well as the potential applicability of these methods in China. The technical potential for CSP-TES in China is significant, but deployment has not yet achieved the targets established by the Chinese government. According to the 12th Five Year Plan for Renewable Energy (2011-2015), CSP was expected to reach 1 GW by 2015 and 3 GW by 2020 in China, yet as of December 2014, deployment totaled only 13.8 MW. One barrier to more rapid deployment is the lack of an incentive specific to CSP, such as a feed-in tariff. The 13th Five Year Plan for Solar Generation (2016-2020), which is under development, presents an opportunity to establish a feed-in tariff specific to CSP. This report, produced under the auspices of the U.S.-China Renewable Energy Partnership, aims to support the development of Chinese incentives that advance CSP deployment goals.

  7. Benchmark Test of Differential Emission Measure Codes and Multi-thermal Energies in Solar Active Regions

    Science.gov (United States)

    Aschwanden, Markus J.; Boerner, Paul; Caspi, Amir; McTiernan, James M.; Ryan, Daniel; Warren, Harry

    2015-10-01

    We compare the ability of 11 differential emission measure (DEM) forward-fitting and inversion methods to constrain the properties of active regions and solar flares by simulating synthetic data using the instrumental response functions of the Solar Dynamics Observatory/ Atmospheric Imaging Assembly (SDO/AIA) and EUV Variability Experiment (SDO/EVE), the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI), and the Geostationary Operational Environmental Satellite/ X-ray Sensor (GOES/XRS). The codes include the single-Gaussian DEM, a bi-Gaussian DEM, a fixed-Gaussian DEM, a linear spline DEM, the spatial-synthesis DEM, the Monte-Carlo Markov Chain DEM, the regularized DEM inversion, the Hinode/ X-Ray Telescope (XRT) method, a polynomial spline DEM, an EVE+GOES, and an EVE+RHESSI method. Averaging the results from all 11 DEM methods, we find the following accuracies in the inversion of physical parameters: the EM-weighted temperature Tw^{fit}/Tw^{sim}=0.9±0.1, the peak emission measure EMp^{fit}/EMp^{sim}=0.6±0.2, the total emission measure EMt^{fit}/EMt^{sim}=0.8±0.3, and the multi-thermal energies E_{th}^{fit}/EM_{th}^{approx}=1.2±0.4. We find that the AIA spatial-synthesis, the EVE+GOES, and the EVE+RHESSI method yield the most accurate results.

  8. Modelling Concentrating Solar Power with Thermal Energy Storage for Integration Studies: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Hummon, M.; Denholm, P.; Jorgenson, J.; Mehos, M.

    2013-10-01

    Concentrating solar power with thermal energy storage (CSP-TES) can provide multiple benefits to the grid, including low marginal cost energy and the ability to levelize load, provide operating reserves, and provide firm capacity. It is challenging to properly value the integration of CSP because of the complicated nature of this technology. Unlike completely dispatchable fossil sources, CSP is a limited energy resource, depending on the hourly and daily supply of solar energy. To optimize the use of this limited energy, CSP-TES must be implemented in a production cost model with multiple decision variables for the operation of the CSP-TES plant. We develop and implement a CSP-TES plant in a production cost model that accurately characterizes the three main components of the plant: solar field, storage tank, and power block. We show the effect of various modelling simplifications on the value of CSP, including: scheduled versus optimized dispatch from the storage tank and energy-only operation versus co-optimization with ancillary services.

  9. Design and Proto-Flight Test Strategy for a Microscale Solar Thermal Engine

    Science.gov (United States)

    Kennedy, F. G.; Palmer, P.; Gibbon, D.

    2002-01-01

    The authors have previously shown that a micro-scale solar thermal engine, using storable monopropellants (e.g., water, ammonia, or hydrazine) and simplified subsystems, augments microsatellite capabilities by permitting velocity changes on the order of 1,500-3,000 m/s. Small satellites have long been seen as "confined" to limited roles in Low Earth Orbit (LEO). Adding significant propulsive capability opens up new roles and missions--among these, communications in geosynchronous earth orbit (GEO), as well as lunar orbit insertion and near-earth asteroid flybys. Transfer times range from as little as 30-40 days (for Geosynchronous Transfer Orbit to GEO) to 275 days for selected near-earth object encounters. This is accomplished by performing moderate thrust (~5 N) firings of the solar thermal engine at perigee and/or apogee. This paper will briefly review benchmark missions and preliminary design choices, concentrating on the selected detailed design and its ramifications for testing and spacecraft operational use. The solar thermal propulsion system is to be built as a proto-qualification/proto-flight unit (i.e., tested to qualification levels and subsequently used in on-orbit operations). This will minimize the number of experimental iterations prior to flight and reduce overall development cost. The testing program will include acoustic, sinusoidal, and random vibration tests, in line with Ariane 5's Ariane Structure for Auxiliary Payloads (ASAP) requirements. As several SSTL enhanced microsatellites have flown aboard Ariane, these figures represent excellent baseline values for the test campaign. Additionally, the solar thermal engine will be constructed so as to ensure compatibility with existing host spacecraft operational protocols. SSTL ground operations are "autonomous and self-checking," requiring the equivalent of only several operators per day to manage numerous small satellite passes. It is important that an advanced propulsion system not compromise

  10. Evaluation of power block arrangements for 100MW scale concentrated solar thermal power generation using top-down design

    Science.gov (United States)

    Post, Alexander; Beath, Andrew; Sauret, Emilie; Persky, Rodney

    2017-06-01

    Concentrated solar thermal power generation poses a unique situation for power block selection, in which a capital intensive heat source is subject to daily and seasonal fluctuations in intensity. In this study, a method is developed to easily evaluate the favourability of different power blocks for converting the heat supplied by a concentrated solar thermal plant into power at the 100MWe scale based on several key parameters. The method is then applied to a range of commercially available power cycles that operate over different temperatures and efficiencies, and with differing capital costs, each with performance and economic parameters selected to be typical of their technology type, as reported in literature. Using this method, the power cycle is identified among those examined that is most likely to result in a minimum levelised cost of energy of a solar thermal plant.

  11. A Conceptual Design Study on the Application of Liquid Metal Heat Transfer Technology to the Solar Thermal Power Plant

    Science.gov (United States)

    Zimmerman, W. F.; Robertson, C. S.; Ehde, C. L.; Divakaruni, S. M.; Stacy, L. E.

    1979-01-01

    Alkali metal heat transfer technology was used in the development of conceptual designs for the transport and storage of sensible and latent heat thermal energy in distributed concentrator, solar Stirling power conversion systems at a power level of 15 kWe per unit. Both liquid metal pumped loop and heat pipe thermal transport were considered; system configurations included: (1) an integrated, focal mounted sodium heat pipe solar receiver (HPSR) with latent heat thermal energy storage; (2) a liquid sodium pumped loop with the latent heat storage, Stirling engine-generator, pump and valves located on the back side of the concentrator; and (3) similar pumped loops serving several concentrators with more centralized power conversion and storage. The focus mounted HPSR was most efficient, lightest and lowest in estimated cost. Design confirmation testing indicated satisfactory performance at all angles of inclination of the primary heat pipes to be used in the solar receiver.

  12. Thermal analysis of a solar collector consisting of V cavities for water heating; Analise termica de um coletor solar composto de cavidades V para aquecimento de agua

    Energy Technology Data Exchange (ETDEWEB)

    Moreira, Michel Fabio de Souza

    2009-03-15

    The solar water heating is carried through, in Brazil, by means of solar heaters compound for collectors flat plate of the type plate-and-pipes, devices that operate in stationary position and they do not require tracking of the sun. A compound collector for some formed V-trough concentrators can be an alternative to the conventional solar collectors flat plate. This compound collector for V-trough is considered, each one, for side-walls which are specularly reflecting surfaces associates in V (equivalent to a triangular gutter). Next to the vertex to each V-trough concentrators an absorber tube is fixed, for flow of the fluid to be heated. Interconnection of the absorbers tubes forms a similar tubular network existing in solar collectors of the type the plate and pipe. V-trough concentrators with the absorbers tubes are made use in series in the interior a prismatic box, which have one of its faces consisting by a glass covering and directed toward incidence of the solar radiation. An analysis of thermal performance of these devices operating stationary and without tracking of the sun is researched. A mathematical model for the computational simulation of the optical and thermal performance of these concentrative devices is elaborated, whose implementation was carried through software EES (Engineering Equation Solver). The efficiency optics of V-trough concentrators with cylindrical absorbers is calculated from the adaptation of the methodology used for Fraidenraich (1994), proposal for Hollands (1971) for V-trough cavities with plain absorbers. The thermal analysis of the considered collector was based on the applied methodology the CPC for Hsieh (1981) and Leao (1989). Relative results to the thermal performance of V-trough concentrators suggest that these configurations are not competitive, technique and economically, with the conventional plain collectors. Although some geometric configurations presented next thermal efficiencies to the conventional plain

  13. Photo-thermal characteristics of water-based Fe3O4@SiO2 nanofluid for solar-thermal applications

    Science.gov (United States)

    Khashan, Saud; Dagher, Sawsan; Omari, Salahaddin Al; Tit, Nacir; Elnajjar, Emad; Mathew, Bobby; Hilal-Alnaqbi, Ali

    2017-05-01

    This work proposes and demonstrates the novel idea of using Fe3O4@SiO2 core/shell structure nanoparticles (NPs) to improve the solar thermal conversion efficiency. Magnetite (Fe3O4) NPs are synthesized by controlled co-precipitation method. Fe3O4@SiO2 NPs are prepared based on sol-gel approach, then characterized. Water-based Fe3O4@SiO2 nanofluid is prepared and usedto illustrate the photo-thermal conversion characteristics of a solar collector under solar simulator. The temperature rise characteristics of the nanofluids are investigated at different heights of the solar collector, for duration of 300 min, under a solar intensity of 1000 W m-2. The experimental results show that Fe3O4@SiO2 NPs have a core/shell structure with spherical morphology and size of about 400 nm. Fe3O4@SiO2/H2O nanofluid enhances the photo-thermal conversion efficiency compared with base fluid and Fe3O4/H2O nanofluid, since the silica coating improves both the thermodynamic stability of the nanofluid and the light absorption effectiveness of the NPs. At a concentration of 1 mg/1 ml of Fe3O4@SiO2/H2O, and with the utilization of kerosene into the solar collector, and exposure for radiation for 5 min, the photo-thermal conversion efficiency has shown an enhancement at the bottom of the collector of about 32.9% compared to the base fluid.

  14. Micro/Nano-Scale Phase Change Systems for Thermal Management and Solar Energy Conversion Applications

    Science.gov (United States)

    Coso, Dusan

    experiments. Structures are manipulated by reduction of pore size to determine if increased capillary pressure can enhance rewetting from heater edges and delay CHF. A comparative study between the two experimental systems indicates that while the capillary limitation is significant in capillary wick experiments, for these well wetted microstructured surfaces used in pool boiling systems the hydrodynamic limitation defined based on heater size causes the occurrence of CHF. Other hierarchical nanowire surfaces containing periodic microscale cavities are investigated as well and are seen to yield a ˜2.4 fold increase in heat transfer coefficient characteristics while not compromising CHF compared to surfaces where cavities are not present. These studies indicate pathways for enhancement of heat transfer coefficient via implementing hierarchical structures, while no clear method in increasing CHF is determined for finite size surfaces of various morphologies. In the second part of this dissertation, solar energy storage is sought in 'phase change' of photochromic molecular systems: the storage of solar energy in the chemical bonds of photosensitive molecules (a photochemical reaction) and subsequent recovery of the energy in a back reaction in the form of heat, reversibly. These molecular systems are interesting alternatives to photovoltaic and solar thermal technologies which cannot satisfy the needs of load leveling, or for portable municipal heating applications. Typically made of organic compounds, these molecules have become known for rapid decomposition, short energy storage time scales and poor energy storing efficiencies. Thus, they have been abandoned as practical solar energy storage systems in the past several decades. On the other hand, organometallic molecular systems have not been extensively probed for these applications. Recent research has indicated that organometallic (fulvalene)diruthenium FvRu2 has demonstrated excellent energy storage characteristic and

  15. Silicon-Light: a European FP7 Project Aiming at High Efficiency Thin Film Silicon Solar Cells on Foil

    DEFF Research Database (Denmark)

    Soppe, W.; Haug, F.-J.; Couty, P.

    2011-01-01

    calculations of ideal nanotextures for light trapping in thin film silicon solar cells; the fabrication of masters and the replication and roll-to-roll fabrication of these nanotextures. Further, results on ITO variants with improved work function are presented. Finally, the status of cell fabrication on foils......Silicon-Light is a European FP7 project, which started January 1st, 2010 and aims at development of low cost, high-efficiency thin film silicon solar cells on foil. Three main routes are explored to achieve these goals: a) advanced light trapping by implementing nanotexturization through UV Nano...... with nanotexture is shown. Microcrystalline and amorphous silicon single junction cells with stable efficiencies with more than 8 % have been made, paving the way towards a-Si/ c-Si tandem cells with more than 11% efficiency....

  16. Solar thermal enhanced oil recovery (STEOR). Sections 2-8. Final report, October 1, 1979-June 30, 1980

    Energy Technology Data Exchange (ETDEWEB)

    Elzinga, E.; Arnold, C.; Allen, D.; Garman, R.; Joy, P.; Mitchell, P. Shaw, H.

    1980-11-01

    The program objectives were: (1) determine the technical, economic, operational, and environmental feasibility of solar thermal enhanced oil recovery using line focusing distributed collectors at Exxon's Edison Field, and (2) estimate the quantity of solar heat which might be applied to domestic enhanced oil recovery. This volume of the report summarizes all of the work done under the contract Statement of Work. Topics include the selection of the solar system, trade-off studies, preliminary design for steam raising, cost estimate for STEOR at Edison Field, the development plan, and a market and economics analysis. (WHK)

  17. Two-stage solar power tower cavity-receiver design and thermal performance analysis

    Science.gov (United States)

    Pang, Liping; Wang, Ting; Li, Ruihua; Yang, Yongping

    2017-06-01

    New type of two-stage solar power tower cavity-receiver is designed and a calculating procedure of radiation, convection and flow under the Gaussian heat flux is established so as to determine the piping layout and geometries in the receiver I and II and the heat flux distribution in different positions is obtained. Then the main thermal performance on water/steam temperature, steam quality, wall temperature along the typical tubes and pressure drop are specified according to the heat transfer and flow characteristics of two-phase flow. Meanwhile, a series of systematic design process is promoted and analysis on thermal performance of the two receivers is conducted. Results show that this type of two-stage cavity-receivers can minimize the size and reduce the mean temperature of receiver I while raise the average heat flux, thus increase the thermal efficiency of the two receivers; besides, the multiple serpentine tubes from header can make a more uniform distribution of the outlet parameters, preventing wall overheated.

  18. Characteristics of thermally reduced graphene oxide and applied for dye-sensitized solar cell counter electrode

    Science.gov (United States)

    Ho, Ching-Yuan; Wang, Hong-Wen

    2015-12-01

    Graphene oxide (GO) was synthesized from a flake-type of graphite powder, which was then reduced to a few layers of graphene sheets using the thermal reduction method. The surface morphology, phase crystallization, and defect states of the reduced graphene were determined from an electron microscope equipped with an energy dispersion spectrometer, X-ray diffraction, Raman spectroscopy, and infrared spectra. After graphene formation, the intercalated defects that existed in the GO were removed, and it became crystalline by observing impurity changes and d-spacing. Dye-sensitized solar cells, using reduced graphene as the counter electrode, were fabricated to evaluate the electrolyte activity and charge transport performance. The electrochemical impedance spectra showed that increasing the thermal reduction temperature could achieve faster electron transport and longer electron lifetime, and result in an energy conversion efficiency of approximately 3.4%. Compared to the Pt counter electrode, the low cost of the thermal reduction method suggests that graphene will enjoy a wide range of potential applications in the field of electronic devices.

  19. Effect of thermal annealing treatment with titanium chelate on buffer layer in inverted polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhiyong [College of Science, Shenyang Agricultural University, Shenyang 110866 (China); Wang, Ning, E-mail: ning_wang@outlook.com [School of Electrical and Electronic and Engineering, Nanyang Technological University 639798 (Singapore); Fu, Yan, E-mail: 1060945062@qq.com [College of Science, Shenyang Agricultural University, Shenyang 110866 (China)

    2016-12-15

    Highlights: • The TIPD layer as electron extraction layer and instead of Ca or LiF. • Impact of the work function of TIPD layer by thermal annealing treatment. • Importance of TIPD layer as electron extraction layer for work function and potential barrier. - Abstract: The solution processable electron extraction layer (EEL) is crucial for polymer solar cells (PSCs). Here, we investigated titanium (diisopropoxide) bis(2,4-pentanedionate) (TIPD) as an EEL and fabricated inverted PSCs with a blend of poly(3-hexylthiophene) (P3HT) and indene-C60 bisadduct (ICBA) acting as the photoactive layer, with a structure of ITO/TIPD/P3HT:ICBA/MoO{sub 3}/Ag. After thermal annealing treatment at 150 °C for 15 min, the PSC performances increased from 3.85% to 6.84% and they achieve stable power conversion efficiency (PCE), with a similar PCE compared with TiO{sub 2} as an EEL by the vacuum evaporated method. Fourier transform infrared spectroscopy (FTIR) and ultraviolet photoelectron spectroscopy (UPS) confirmed that the TIPD decomposed and formed the Ti=O bond, and the energy level of the lowest unoccupied molecular orbital and the highest occupied molecular orbital increased. The space charge limited current (SCLC) measurements further confirmed the improvement in electron collection and the transport ability using TIPD as the EEL and thermal annealing.

  20. Standard Test Method for Determining Thermal Performance of Tracking Concentrating Solar Collectors

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    1987-01-01

    1.1 This test method covers the determination of thermal performance of tracking concentrating solar collectors that heat fluids for use in thermal systems. 1.2 This test method applies to one- or two-axis tracking reflecting concentrating collectors in which the fluid enters the collector through a single inlet and leaves the collector through a single outlet, and to those collectors where a single inlet and outlet can be effectively provided, such as into parallel inlets and outlets of multiple collector modules. 1.3 This test method is intended for those collectors whose design is such that the effects of diffuse irradiance on performance is negligible and whose performance can be characterized in terms of direct irradiance. Note 1—For purposes of clarification, this method shall apply to collectors with a geometric concentration ratio of seven or greater. 1.4 The collector may be tested either as a thermal collection subsystem where the effects of tracking errors have been essentially removed from t...