WorldWideScience

Sample records for model solar energy

  1. Solar energy estimation using REST2 model

    Directory of Open Access Journals (Sweden)

    M. Rizwan, Majid Jamil, D. P. Kothari

    2010-03-01

    Full Text Available The network of solar energy measuring stations is relatively rare through out the world. In India, only IMD (India Meteorological Department Pune provides data for quite few stations, which is considered as the base data for research purposes. However, hourly data of measured energy is not available, even for those stations where measurement has already been done. Due to lack of hourly measured data, the estimation of solar energy at the earth’s surface is required. In the proposed study, hourly solar energy is estimated at four important Indian stations namely New Delhi, Mumbai, Pune and Jaipur keeping in mind their different climatic conditions. For this study, REST2 (Reference Evaluation of Solar Transmittance, 2 bands, a high performance parametric model for the estimation of solar energy is used. REST2 derivation uses the two-band scheme as used in the CPCR2 (Code for Physical Computation of Radiation, 2 bands but CPCR2 does not include NO2 absorption, which is an important parameter for estimating solar energy. In this study, using ground measurements during 1986-2000 as reference, a MATLAB program is written to evaluate the performance of REST2 model at four proposed stations. The solar energy at four stations throughout the year is estimated and compared with CPCR2. The results obtained from REST2 model show the good agreement against the measured data on horizontal surface. The study reveals that REST2 models performs better and evaluate the best results as compared to the other existing models under cloudless sky for Indian climatic conditions.

  2. Solar radiation practical modeling for renewable energy applications

    CERN Document Server

    Myers, Daryl Ronald

    2013-01-01

    Written by a leading scientist with over 35 years of experience working at the National Renewable Energy Laboratory (NREL), Solar Radiation: Practical Modeling for Renewable Energy Applications brings together the most widely used, easily implemented concepts and models for estimating broadband and spectral solar radiation data. The author addresses various technical and practical questions about the accuracy of solar radiation measurements and modeling. While the focus is on engineering models and results, the book does review the fundamentals of solar radiation modeling and solar radiation m

  3. Solar Energy.

    Science.gov (United States)

    Eaton, William W.

    Presented is the utilization of solar radiation as an energy resource principally for the production of electricity. Included are discussions of solar thermal conversion, photovoltic conversion, wind energy, and energy from ocean temperature differences. Future solar energy plans, the role of solar energy in plant and fossil fuel production, and…

  4. Solar energy

    Science.gov (United States)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  5. Solar energy

    Science.gov (United States)

    Rapp, D.

    1981-01-01

    The book opens with a review of the patterns of energy use and resources in the United States, and an exploration of the potential of solar energy to supply some of this energy in the future. This is followed by background material on solar geometry, solar intensities, flat plate collectors, and economics. Detailed attention is then given to a variety of solar units and systems, including domestic hot water systems, space heating systems, solar-assisted heat pumps, intermediate temperature collectors, space heating/cooling systems, concentrating collectors for high temperatures, storage systems, and solar total energy systems. Finally, rights to solar access are discussed.

  6. Spatial Modelling of Solar energy Potential in Kenya

    Directory of Open Access Journals (Sweden)

    Francis Omondi Oloo

    2015-06-01

    Full Text Available Solar energy is one of the readily available renewable energy resources in the developing countries within the tropical region. Kenya is one of the countries which receive an average of approximately 6.5 sunshine hours in a single day throughout the year. However, there is slow adoption of solar energy resources in the country due to limited information on the spatial variability solar energy potential. This study aims at assessing the potential of photovoltaic solar energy in Kenya. The factors that influence incident solar radiation which were considered in this task included atmospheric transmissivity and topography. The influence of atmospheric transmissivity was factored in by modelling monthly transmissivity factors from a combination of cloud cover, diffuse ratios and the effect of altitude. The contribution of topography was included by applying hemispherical viewshed analysis to determine the amount of incident global radiation on the surface based on the orientation of the terrain. GIS concepts were used to integrate the spatial datasets from different themes. The results showed that, about 70% of the land area in Kenya has the potential of receiving approximately 5kWh/m2/day throughout the year. In outline, this work successfully assessed the spatio-temporal variability in the characteristics of solar energy potential in Kenya and can be used as a basis for policy support in the country.

  7. Solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Sommer-Larsen, P.; Krebs, F.C. (Risoe DTU, Roskilde (Denmark)); Plaza, D.M. (Plataforma Solar de Almeria-CIEMAT (Spain))

    2010-11-15

    Solar energy is the most abundant energy resource on earth. In a sustainable future with an ever-increasing demand for energy, we will need to use this resource better. Solar energy technologies either convert sunlight directly into heat and electrical energy or use it to power chemical conversions which create 'solar fuels' or synthetic compounds. Solar heating technologies have developed steadily for many years and solar heating and cooling is one of the world's commonest renewable energy technologies. This chapter, however, focuses on technologies for electricity production and touches more briefly on the prospects for solar fuels. The section on Danish perspectives also discusses solar thermal heating in district heating plants. In recent decades, two technologies for converting solar energy into electrical energy have dominated: photovoltaics (PV) and concentrating solar power (CSP). Today's silicon and thin-film PV technologies are advancing steadily, with new materials and technologies constantly being developed, and there are clear roadmaps for lowering production costs. In the discussion below we assess the maturation potential of currently emerging PV technologies within the next 40 years. Concentrating solar power is already a proven technology, and below we evaluate its potential to become a substantial part of the energy mix by 2050. Solar fuels cover a range of technologies. The chapter is to a great extent based on two recent roadmaps from the International Energy Agency (IEA). Many reports, predictions, scenarios and roadmaps for solar energy deployment exist. The IEA predictions for the penetration of solar energy in the future energy system are low relative to many of the other studies. The IEA roadmaps, however, cover most aspects of the future deployment of the technologies and reference older work. (Author)

  8. Sustainable business models for wind and solar energy in Romania

    Directory of Open Access Journals (Sweden)

    Nichifor Maria Alexandra

    2015-06-01

    Full Text Available Renewable energy has become a crucial element for the business environment as the need for new energy resources and the degree of climate change are increasing. As developed economies strive towards greater progress, sustainable business models are of the essence in order to maintain a balance between the triple bottom line: people, planet and profit. In recent years, European Union countries have installed important capacities of renewable energy, especially wind and solar energy to achieve this purpose. The objective of this article is to make a comparative study between the current sustainable business models implemented in companies that are active in the wind and solar energy sector in Romania. Both sectors underwent tremendous changes in the last two years due to changing support schemes which have had a significant influence on the mechanism of the renewable energy market, as well as on its development. Using the classical Delphi method, based on questionnaires and interviews with experts in the fields of wind and solar energy, this paper offers an overview of the sustainable business models of wind and solar energy companies, both sectors opting for the alternative of selling electricity to trading companies as a main source of revenue until 2013 and as the main future trend until 2020. Furthermore, the participating wind energy companies noted a pessimistic outlook of future investments due to legal instability that made them to reduce their projects in comparison to PV investments, which are expected to continue. The subject of the article is of interest to scientific literature because sustainable business models in wind and photovoltaic energy have been scarcely researched in previous articles and are essential in understanding the activity of the companies in these two fields of renewable energy.

  9. Models for efficient integration of solar energy

    DEFF Research Database (Denmark)

    Bacher, Peder

    . Finally a procedure for identication of a suitable model for the heat dynamics of a building is presented. The applied models are greybox model based on stochastic dierential equations and the identication is carried out with likelihood ratio tests. The models can be used for providing detailed...

  10. Solar Radiation Model for Development and Control of Solar Energy Sources

    Directory of Open Access Journals (Sweden)

    Dominykas Vasarevičius

    2016-06-01

    Full Text Available The model of solar radiation, which takes into account direct, diffused and reflected components of solar energy, has been presented. Model is associated with geographical coordinates and local time of every day of the year. It is shown that using analytic equations for modelling the direct component, it is possible to adopt it for embedded systems with low computational power and use in solar tracking applications. Reflected and diffused components are especially useful in determining the performance of photovoltaic modules in certain location and surroundings. The statistical method for cloud layer simulation based on local meteorological data is offered. The presented method can’t be used for prediction of weather conditions but it provides patterns of solar radiation in time comparable to those measured with pyranometer. Cloud layer simulation together with total solar radiation model is a useful tool for development and analysis of maximum power point tracking controllers for PV modules.

  11. Solar-hydrogen energy system model for Libya

    Energy Technology Data Exchange (ETDEWEB)

    Eljrushi, G.S.

    1987-01-01

    A solar-hydrogen energy-system model for Libya was developed, obtaining relationships for and between the main energy and energy related parameters of Libya and the world. The parameters included are: population, energy demand, fossil-fuel production, fossil-fuel resources, hydrogen production, hydrogen introduction rates, energy prices, gross domestic product, pollution and quality of life. The trends of these parameters with and without hydrogen introduction were investigated over a period of time - through the year 2100. The results indicate that the fossil-fuel resources in Libya could be exhausted, due to production for local and export demands, within three to four decades unless serious measures for reducing production are taken. The results indicate that adopting solar-hydrogen energy system would extend the availability of fossil-fuel resources for a longer time period, reduce pollution, improve quality of life and establish a permanent energy system for Libya. It also shows that eventually Libya could export hydrogen in lieu of oil and natural gas.

  12. Solar energy conversion systems

    CERN Document Server

    Brownson, Jeffrey R S

    2013-01-01

    Solar energy conversion requires a different mind-set from traditional energy engineering in order to assess distribution, scales of use, systems design, predictive economic models for fluctuating solar resources, and planning to address transient cycles and social adoption. Solar Energy Conversion Systems examines solar energy conversion as an integrative design process, applying systems thinking methods to a solid knowledge base for creators of solar energy systems. This approach permits different levels of access for the emerging broad audience of scientists, engineers, architects, planners

  13. A Groundwater Model to Assess Water Resource Impacts at the Imperial East Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); O' Connor, Ben L. [Argonne National Lab. (ANL), Argonne, IL (United States); Tompson, Andrew F.B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2013-12-01

    The purpose of this study is to develop a groundwater flow model to examine the influence of potential groundwater withdrawal to support the utility-scale solar energy development at the Imperial East Solar Energy Zone (SEZ) as a part of the Bureau of Land Management’s (BLM) solar energy program.

  14. A Groundwater Model to Assess Water Resource Impacts at the Brenda Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John [Argonne National Lab. (ANL), Argonne, IL (United States); Carr, Adrianne E. [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Chris [Argonne National Lab. (ANL), Argonne, IL (United States); Bowen, Esther E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2013-12-01

    The purpose of this study is to develop a groundwater flow model to examine the influence of potential groundwater withdrawal to support utility-scale solar energy development at the Brenda Solar Energy Zone (SEZ), as a part of the Bureau of Land Management’s (BLM’s) Solar Energy Program.

  15. dynamic modeling of natural convection solar energy collectors for ...

    African Journals Online (AJOL)

    NIJOTECH

    terms for the plates' temperatures showed the transient contribution to be very ... conversion of solar energy is so low. (about 1 ... ovens, and low temperature and industrial ..... White, G.K. Experimental Techniques in Low Temperature Physics.

  16. Collecting Solar Energy. Solar Energy Education Project.

    Science.gov (United States)

    O'Brien, Alexander

    This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

  17. Collecting Solar Energy. Solar Energy Education Project.

    Science.gov (United States)

    O'Brien, Alexander

    This solar energy learning module for use with junior high school students offers a list of activities, a pre-post test, job titles, basic solar energy vocabulary, and diagrams of solar energy collectors and installations. The purpose is to familiarize students with applications of solar energy and titles of jobs where this knowledge could be…

  18. Solar Energy: Solar System Economics.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar system economics is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies.…

  19. SOLINS- SOLAR INSOLATION MODEL FOR COMPUTING AVAILABLE SOLAR ENERGY TO A SURFACE OF ARBITRARY ORIENTATION

    Science.gov (United States)

    Smith, J. H.

    1994-01-01

    This computer program, SOLINS, was developed to aid engineers and solar system designers in the accurate modeling of the average hourly solar insolation on a surface of arbitrary orientation. The program can be used to study insolation problems specific to residential and commercial applications where the amount of space available for solar collectors is limited by shadowing problems, energy output requirements, and costs. For tandem rack arrays, SOLINS will accommodate the use of augmentation reflectors built into the support structure to increase insolation values at the collector surface. As the use of flat plate solar collectors becomes more prevalent in the building industry, the engineer and designer must have the capability to conduct extensive sensitivity analyses on the orientation and location of solar collectors. SOLINS should prove to be a valuable aid in this area of engineering. SOLINS uses a modified version of the National Bureau of Standards model to calculate the direct, diffuse, and reflected components of total insolation on a tilted surface with a given azimuthal orientation. The model is based on the work of Liu and Jordan with corrections by Kusuda and Ishii to account for early morning and late afternoon errors. The model uses a parametric description of the average day solar climate to generate monthly average day profiles by hour of the insolation level on the collector surface. The model includes accommodation of user specified ground and landscape reflectivities at the collector site. For roof or ground mounted, tilted arrays, SOLINS will calculate insolation including the effects of shadowing and augmentation reflectors. The user provides SOLINS with data describing the array design, array orientation, the month, the solar climate parameter, the ground reflectance, and printout control specifications. For the specified array and environmental conditions, SOLINS outputs the hourly insolation the array will receive during an average day

  20. Enhancement of Solar Energy Representation in the GCAM Model

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Steven J.; Volke, April C.; Delgado Arias, Sabrina

    2010-02-01

    The representation of solar technologies in a research version of the GCAM (formerly MiniCAM) integrated assessment model have been enhanced to add technologies, improve the underlying data, and improve the interaction with the rest of the model. We find that the largest potential impact from the inclusion of thermal Concentrating Solar Power plants, which supply a substantial portion of electric generation in sunny regions of the world. Drawing on NREL research, domestic Solar Hot Water technologies have also been added in the United States region where this technology competes with conventional electric and gas technologies. PV technologies are as implemented in the CCTP scenarios, drawing on NREL cost curves for the United States, extrapolated to other world regions using a spatial analysis of population and solar resources.

  1. Solar energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Sayigh, A.A.M. (ed.)

    1977-01-01

    The scope and advantages of solar energy are dealt with. The nature of the sun, the solar radiation spectrum, the estimation of total, direct, and diffuse radiation, and the heat transfer fundamentals for solar energy application are explained. The fundamentals, fabrication, and uses of various water and air heaters are outlined. Optics and concentrating collectors are dealt with, as well as solar furnaces. The various applications of solar energy are discussed, namely, solar pond, solar distillation, photovoltaic conversion of solar energy, solar refrigeration, solar hydrogen production, space applications, and solar measuring equipment. The cost of solar appliances is discussed. (MHR)

  2. Solar Energy and You.

    Science.gov (United States)

    Conservation and Renewable Energy Inquiry and Referral Service (DOE), Silver Spring, MD.

    This booklet provides an introduction to solar energy by discussing: (1) how a home is heated; (2) how solar energy can help in the heating process; (3) the characteristics of passive solar houses; (4) the characteristics of active solar houses; (5) how solar heat is stored; and (6) other uses of solar energy. Also provided are 10 questions to…

  3. BLM Solar Energy Zones

    Data.gov (United States)

    Bureau of Land Management, Department of the Interior — Priority development areas for utility-scale solar energy facilities as identified in the Solar PEIS Record of Decision. An additional Solar Energy Zone identified...

  4. P50/P90 Analysis for Solar Energy Systems Using the System Advisor Model: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Dobos, A. P.; Gilman, P.; Kasberg, M.

    2012-06-01

    To secure competitive financing for a solar energy generation project, the economic risk associated with interannual solar resource variability must be quantified. One way to quantify this risk is to calculate exceedance probabilities representing the amount of energy expected to be produced by a plant. Many years of solar radiation and metereological data are required to determine these values, often called P50 or P90 values for the level of certainty they represent. This paper describes the two methods implemented in the National Renewable Energy Laboratory's System Advisor Model (SAM) to calculate P50 and P90 exceedance probabilities for solar energy projects. The methodology and supporting data sets are applicable to photovoltaic, solar water heating, and concentrating solar power (CSP) systems.

  5. Potential of Solar Energy in Kota Kinabalu, Sabah: An Estimate Using a Photovoltaic System Model

    Science.gov (United States)

    Markos, F. M.; Sentian, J.

    2016-04-01

    Solar energy is becoming popular as an alternative renewable energy to conventional energy source, particularly in the tropics, where duration and intensity of solar radiation are longer. This study is to assess the potential of solar energy generated from solar for Kota Kinabalu, a rapidly developing city in the State of Sabah, Malaysia. A year data of solar radiation was obtained using pyranometer, which was located at Universiti Malaysia Sabah (6.0367° N, 116.1186° E). It was concluded that the annual average solar radiation received in Kota Kinabalu was 182 W/m2. In estimating the potential energy generated from solar for Kota Kinabalu city area, a photovoltaic (PV) system model was used. The results showed that, Kota Kinabalu is estimated to produce 29,794 kWh/m2 of electricity from the solar radiation received in a year. This is equivalent to 0.014 MW of electricity produced just by using one solar panel. Considering the power demand in Sabah by 2020 is 1,331 MW, this model showed that the solar energy can contribute around 4% of energy for power demand, with 1 MW capacity of the PV system. 1 MW of PV system installation will require about 0.0328% from total area of the city. This assessment could suggest that, exploration for solar power energy as an alternative source of renewable energy in the city can be optimised and designed to attain significant higher percentage of contribution to the energy demand in the state.

  6. Solar Energy

    OpenAIRE

    Sommer-Larsen, Peter; Furbo, Simon

    2014-01-01

    This thesis is about Photovoltaic (PV) cells and its stresses in various directions by calculating the power generated using solar cells under different conditions to improve its efficiency. Our research studies found that using multi-junction cells with larger substrates can increase the efficiency to some extent which in practice is limited to 43 percent. The experiment was conducted using ten solar cells each with an area of 20.9〖cm〗 ^2, where each cell gives 0.5 V and 0.4 A and a 1.25 Ω r...

  7. Solar Energy Systems

    Science.gov (United States)

    1984-01-01

    Calibrated in kilowatt hours per square meter, the solar counter produced by Dodge Products, Inc. provides a numerical count of the solar energy that has accumulated on a surface. Solar energy sensing, measuring and recording devices in corporate solar cell technology developed by Lewis Research Center. Customers for their various devices include architects, engineers and others engaged in construction and operation of solar energy facilities; manufacturers of solar systems or solar related products, such as glare reducing windows; and solar energy planners in federal and state government agencies.

  8. Solar energy an introduction

    CERN Document Server

    Mackay, Michael E

    2015-01-01

    Solar Energy presents an introduction to all aspects of solar energy, from photovoltaic devices to active and passive solar thermal energy conversion, giving both a detailed and broad perspective of the field. It is aimed at the beginner involved in solar energy or a related field, or for someone wanting to gain a broader perspective of solar energy technologies. A chapter considering solar radiation, basic principles applied to solar energy, semiconductor physics, and light absorption brings the reader on equal footing with the technology of either solar generated electrical current or useful heat. Details of how a solar cell works and then production of current from a photovoltaic device is discussed. Characterization of a solar cell is examined, allowing one the ability to interpret the current-voltage relation, followed by discussion of parameter extraction from this relation. This information can be used to understand what limits the performance of a given solar cell with the potential to optimize its pe...

  9. A logistic model for magnetic energy storage in solar active regions

    Institute of Scientific and Technical Information of China (English)

    Hua-Ning Wang; Yan-Mei Cui; Han He

    2009-01-01

    Previous statistical analyses of a large number of SOHO/MDI full disk longitu-dinal magnetograms provided a result that demonstrated how responses of solar flares to photospheric magnetic properties can be fitted with sigmoid functions. A logistic model reveals that these fitted sigmoid functions might be related to the free energy storage process in solar active regions. Although this suggested model is rather simple, the free energy level of active regions can be estimated and the probability of a solar flare with importance over a threshold can be forecast within a given time window.

  10. Alternatives in solar energy

    Science.gov (United States)

    Schueler, D. G.

    1978-01-01

    Although solar energy has the potential of providing a significant source of clean and renewable energy for a variety of applications, it is expected to penetrate the nation's energy economy very slowly. The alternative solar energy technologies which employ direct collection and conversion of solar radiation as briefly described.

  11. Solar energy directories

    Energy Technology Data Exchange (ETDEWEB)

    Frankena, F.

    1984-01-01

    This annotated bibliography lists 275 directories relating to solar energy and renewable energy resources. The references include the newsletters and in-house publications of small firms and groups, plans and designs for solar housing, catalogs, and directories of agencies and organizations involved in solar energy. The references are listed in alphabetical order.

  12. Solar Energy Automobile

    OpenAIRE

    He, Jianhua

    2014-01-01

    The thesis was to design a solar energy automobile, which is using solar power as energy re-source. At the moment, Finland was chosen as an example place. It was necessary to calculate the related data, which are the solar angle and the day length when designing the solar energy automobile. Also the seats and dashboard to improve the performance. Actually, in Finland it is possible to use solar energy automobile in summer. But in winter, the day length is so short and the solar constant i...

  13. Solar Energy Automobile

    OpenAIRE

    He, Jianhua

    2014-01-01

    The thesis was to design a solar energy automobile, which is using solar power as energy re-source. At the moment, Finland was chosen as an example place. It was necessary to calculate the related data, which are the solar angle and the day length when designing the solar energy automobile. Also the seats and dashboard to improve the performance. Actually, in Finland it is possible to use solar energy automobile in summer. But in winter, the day length is so short and the solar constant i...

  14. Solar energy emplacement developer

    Science.gov (United States)

    Mortensen, Michael; Sauls, Bob

    1991-01-01

    A preliminary design was developed for a Lunar Power System (LPS) composed of photovoltaic arrays and microwave reflectors fabricated from lunar materials. The LPS will collect solar energy on the surface of the Moon, transform it into microwave energy, and beam it back to Earth where it will be converted into usable energy. The Solar Energy Emplacement Developer (SEED) proposed will use a similar sort of solar energy collection and dispersement to power the systems that will construct the LPS.

  15. Solar Energy Technician/Installer

    Science.gov (United States)

    Moore, Pam

    2007-01-01

    Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

  16. Solar Energy Technician/Installer

    Science.gov (United States)

    Moore, Pam

    2007-01-01

    Solar power (also known as solar energy) is solar radiation emitted from the sun. Large panels that absorb the sun's energy as the sun beats down on them gather solar power. The energy in the rays can be used for heat (solar thermal energy) or converted to electricity (photovoltaic energy). Each solar energy project, from conception to…

  17. Experimenting with Solar Energy

    Science.gov (United States)

    Roman, Harry T.

    2004-01-01

    Over the past 25 years, the author has had the opportunity to study the subject of solar energy and to get involved with the installation, operation, and testing of solar energy systems. His work has taken him all over the United States and put him in contact with solar experts from around the world. He has also had the good fortune of seeing some…

  18. Solar energy modulator

    Science.gov (United States)

    Hale, R. R. (Inventor); Mcdougal, A. R.

    1984-01-01

    A module is described with a receiver having a solar energy acceptance opening and supported by a mounting ring along the optic axis of a parabolic mirror in coaxial alignment for receiving solar energy from the mirror, and a solar flux modulator plate for varying the quantity of solar energy flux received by the acceptance opening of the module. The modulator plate is characterized by an annular, plate-like body, the internal diameter of which is equal to or slightly greater than the diameter of the solar energy acceptance opening of the receiver. Slave cylinders are connected to the modulator plate for supporting the plate for axial displacement along the axis of the mirror, therby shading the opening with respect to solar energy flux reflected from the surface of the mirror to the solar energy acceptance opening.

  19. Toward a mathematical model of solar radiation for engineering analysis of solar energy systems

    Science.gov (United States)

    Hamilton, C. L.; Reid, M. S.

    1976-01-01

    The currently most-used insolation model and what improvements might be made in it to better suit it for use in designing energy systems is discussed. An approach to constructing an upgraded model is sketched.

  20. Solar Energy: Heat Transfer.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat transfer is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The…

  1. Solar Energy: Heat Storage.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on heat storage is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  2. Solar Energy: Home Heating.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on home heating is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies. The module…

  3. Estimating Roof Solar Energy Potential in the Downtown Area Using a GPU-Accelerated Solar Radiation Model and Airborne LiDAR Data

    Directory of Open Access Journals (Sweden)

    Yan Huang

    2015-12-01

    Full Text Available Solar energy, as a clean and renewable resource is becoming increasingly important in the global context of climate change and energy crisis. Utilization of solar energy in urban areas is of great importance in urban energy planning, environmental conservation, and sustainable development. However, available spaces for solar panel installation in cities are quite limited except for building roofs. Furthermore, complex urban 3D morphology greatly affects sunlit patterns on building roofs, especially in downtown areas, which makes the determination of roof solar energy potential a challenging task. The object of this study is to estimate the solar radiation on building roofs in an urban area in Shanghai, China, and select suitable spaces for installing solar panels that can effectively utilize solar energy. A Graphic Processing Unit (GPU-based solar radiation model named SHORTWAVE-C simulating direct and non-direct solar radiation intensity was developed by adding the capability of considering cloud influence into the previous SHORTWAVE model. Airborne Light Detection and Ranging (LiDAR data was used as the input of the SHORTWAVE-C model and to investigate the morphological characteristics of the study area. The results show that the SHORTWAVE-C model can accurately estimate the solar radiation intensity in a complex urban environment under cloudy conditions, and the GPU acceleration method can reduce the computation time by up to 46%. Two sites with different building densities and rooftop structures were selected to illustrate the influence of urban morphology on the solar radiation and solar illumination duration. Based on the findings, an object-based method was implemented to identify suitable places for rooftop solar panel installation that can fully utilize the solar energy potential. Our study provides useful strategic guidelines for the selection and assessment of roof solar energy potential for urban energy planning.

  4. Solar energy engineering

    Energy Technology Data Exchange (ETDEWEB)

    Hsieh, J.S.

    1986-01-01

    This book introduces the reader to solar energy engineering, covering topics such as radiation, absorption, its practical applications in space and hot water heating, and solar geometrical and geographical forms.

  5. Modeling energy production of solar thermal systems and wind turbines for installation at corn ethanol plants

    Science.gov (United States)

    Ehrke, Elizabeth

    Nearly every aspect of human existence relies on energy in some way. Most of this energy is currently derived from fossil fuel resources. Increasing energy demands coupled with environmental and national security concerns have facilitated the move towards renewable energy sources. Biofuels like corn ethanol are one of the ways the U.S. has significantly reduced petroleum consumption. However, the large energy requirement of corn ethanol limits the net benefit of the fuel. Using renewable energy sources to produce ethanol can greatly improve its economic and environmental benefits. The main purpose of this study was to model the useful energy received from a solar thermal array and a wind turbine at various locations to determine the feasibility of applying these technologies at ethanol plants around the country. The model calculates thermal energy received from a solar collector array and electricity generated by a wind turbine utilizing various input data to characterize the equipment. Project cost and energy rate inputs are used to evaluate the profitability of the solar array or wind turbine. The current state of the wind and solar markets were examined to give an accurate representation of the economics of each industry. Eighteen ethanol plant locations were evaluated for the viability of a solar thermal array and/or wind turbine. All ethanol plant locations have long payback periods for solar thermal arrays, but high natural gas prices significantly reduce this timeframe. Government incentives will be necessary for the economic feasibility of solar thermal arrays. Wind turbines can be very profitable for ethanol plants in the Midwest due to large wind resources. The profitability of wind power is sensitive to regional energy prices. However, government incentives for wind power do not significantly change the economic feasibility of a wind turbine. This model can be used by current or future ethanol facilities to investigate or begin the planning process for a

  6. Energy balance in the solar transition region. II - Effects of pressure and energy input on hydrostatic models

    Science.gov (United States)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1991-01-01

    The radiation of energy by hydrogen lines and continua in hydrostatic energy-balance models of the transition region between the solar chromosphere and corona is studied using models which assume that mechanical or magnetic energy is dissipated in the hot corona and is then transported toward the chromosphere down the steep temperature gradient of the transition region. These models explain the average quiet sun and also the entire range of variability of the Ly-alpha lines. The relations between the downward energy flux, the pressure of the transition region, and the different hydrogen emission are described.

  7. High-Energy Aspects of Solar Flares: Observations and Models

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Wei [Lockheed Martin Solar and Astrophysics Laboratory; Guo, Fan [Los Alamos National Laboratory

    2015-07-21

    The paper begins by describing the structure of the Sun, with emphasis on the corona. The Sun is a unique plasma laboratory, which can be probed by Sun-grazing comets, and is the driver of space weather. Energization and particle acceleration mechanisms in solar flares is presented; magnetic reconnection is key is understanding stochastic acceleration mechanisms. Then coupling between kinetic and fluid aspects is taken up; the next step is feedback of atmospheric response to the acceleration process – rapid quenching of acceleration. Future challenges include applications of stochastic acceleration to solar energetic particles (SEPs), Fermi γ-rays observations, fast-mode magnetosonic wave trains in a funnel-shaped wave guide associated with flare pulsations, and the new SMEX mission IRIS (Interface Region Imaging Spectrograph),

  8. A Different View of Solar Spectral Irradiance Variations: Modeling Total Energy over Six-Month Intervals.

    Science.gov (United States)

    Woods, Thomas N; Snow, Martin; Harder, Jerald; Chapman, Gary; Cookson, Angela

    A different approach to studying solar spectral irradiance (SSI) variations, without the need for long-term (multi-year) instrument degradation corrections, is examining the total energy of the irradiance variation during 6-month periods. This duration is selected because a solar active region typically appears suddenly and then takes 5 to 7 months to decay and disperse back into the quiet-Sun network. The solar outburst energy, which is defined as the irradiance integrated over the 6-month period and thus includes the energy from all phases of active region evolution, could be considered the primary cause for the irradiance variations. Because solar cycle variation is the consequence of multiple active region outbursts, understanding the energy spectral variation may provide a reasonable estimate of the variations for the 11-year solar activity cycle. The moderate-term (6-month) variations from the Solar Radiation and Climate Experiment (SORCE) instruments can be decomposed into positive (in-phase with solar cycle) and negative (out-of-phase) contributions by modeling the variations using the San Fernando Observatory (SFO) facular excess and sunspot deficit proxies, respectively. These excess and deficit variations are fit over 6-month intervals every 2 months over the mission, and these fitted variations are then integrated over time for the 6-month energy. The dominant component indicates which wavelengths are in-phase and which are out-of-phase with solar activity. The results from this study indicate out-of-phase variations for the 1400 - 1600 nm range, with all other wavelengths having in-phase variations.

  9. Control of Solar Energy Systems

    CERN Document Server

    Camacho, Eduardo F; Rubio, Francisco R; Martínez, Diego

    2012-01-01

    Control of Solar Energy Systems details the main solar energy systems, problems involved with their control, and how control systems can help in increasing their efficiency.  After a brief introduction to the fundamental concepts associated with the use of solar energy in both photovoltaic and thermal plants, specific issues related to control of solar systems are embarked upon. Thermal energy systems are then explored in depth, as well as  other solar energy applications such as solar furnaces and solar refrigeration systems. Problems of variable generation profile and of the contribution of many solar plants to the same grid system are considered with the necessary integrated and supervisory control solutions being discussed. The text includes material on: ·         A comparison of basic and advanced control methods for parabolic troughs from PID to nonlinear model-based control; ·         solar towers and solar tracking; ·         heliostat calibration, characterization and off...

  10. Strategic Design, Optimization, and Modelling Issues of Net-Zero Energy Solar Buildings

    OpenAIRE

    ATHIENITIS, Andreas; Attia, Shady

    2010-01-01

    The design of net-zero energy solar buildings (NZESBs) presents a challenge because there is no established design strategy to systematically reach this goal and many of the available building energy tools have limited applicability for such advanced buildings. This paper reviews current design practice and tools for designing NZESBs through a literature review and a survey. It also discusses modelling issues and presents the procedure used in several redesign and optimization case studies of...

  11. Physics of solar energy

    CERN Document Server

    Chen, C Julian

    2011-01-01

    The definitive guide to the science of solar energy You hold in your hands the first, and only, truly comprehensive guide to the most abundant and most promising source of alternative energy-solar power. In recent years, all major countries in the world have been calling for an energy revolution. The renewable energy industry will drive a vigorous expansion of the global economy and create more ""green"" jobs. The use of fossil fuels to power our way of living is moving toward an inevitable end, with sources of coal, petroleum, and natural gas being fiercely depleted. Solar energy

  12. Forecasting Optimal Solar Energy Supply in Jiangsu Province (China: A Systematic Approach Using Hybrid of Weather and Energy Forecast Models

    Directory of Open Access Journals (Sweden)

    Xiuli Zhao

    2014-01-01

    Full Text Available The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, “least-cost,” and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor.

  13. Forecasting Optimal Solar Energy Supply in Jiangsu Province (China): A Systematic Approach Using Hybrid of Weather and Energy Forecast Models

    Science.gov (United States)

    Zhao, Xiuli; Yiranbon, Ethel

    2014-01-01

    The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, “least-cost,” and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor. PMID:24511292

  14. Forecasting optimal solar energy supply in Jiangsu Province (China): a systematic approach using hybrid of weather and energy forecast models.

    Science.gov (United States)

    Zhao, Xiuli; Asante Antwi, Henry; Yiranbon, Ethel

    2014-01-01

    The idea of aggregating information is clearly recognizable in the daily lives of all entities whether as individuals or as a group, since time immemorial corporate organizations, governments, and individuals as economic agents aggregate information to formulate decisions. Energy planning represents an investment-decision problem where information needs to be aggregated from credible sources to predict both demand and supply of energy. To do this there are varying methods ranging from the use of portfolio theory to managing risk and maximizing portfolio performance under a variety of unpredictable economic outcomes. The future demand for energy and need to use solar energy in order to avoid future energy crisis in Jiangsu province in China require energy planners in the province to abandon their reliance on traditional, "least-cost," and stand-alone technology cost estimates and instead evaluate conventional and renewable energy supply on the basis of a hybrid of optimization models in order to ensure effective and reliable supply. Our task in this research is to propose measures towards addressing optimal solar energy forecasting by employing a systematic optimization approach based on a hybrid of weather and energy forecast models. After giving an overview of the sustainable energy issues in China, we have reviewed and classified the various models that existing studies have used to predict the influences of the weather influences and the output of solar energy production units. Further, we evaluate the performance of an exemplary ensemble model which combines the forecast output of two popular statistical prediction methods using a dynamic weighting factor.

  15. 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.

  16. Solar Energy: Solar and the Weather.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar and the weather is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy technologies.…

  17. Solar Renewable Energy. Teaching Unit.

    Science.gov (United States)

    Buchanan, Marion; And Others

    This unit develops the concept of solar energy as a renewable resource. It includes: (1) an introductory section (developing understandings of photosynthesis and impact of solar energy); (2) information on solar energy use (including applications and geographic limitations of solar energy use); and (3) future considerations of solar energy…

  18. RANCANG BANGUN KONVERSI ENERGI SURYA MENJADI ENERGI LISTRIK DENGAN MODEL ELEVATED SOLAR TOWER

    Directory of Open Access Journals (Sweden)

    Zainul Hasan, Erika Rani

    2012-05-01

    31.600Lux, 43 300 Lux, and 56,000 Lux. Dari hasil penelitian tersebut menunjukkan bahwa efisiensi panas pada kolektor tidak konstan. Efisiensi kolektor tertinggi mencapai 83,92% sedangkan terendah mencapai 22,55% dengan rata-rata sebesar 57%. Dan efisiensi sistem dari alat konversi tersebut tertinggi mencapai 0,01% sedangkan terendah mencapai 0,0022% dengan rata-rata efisiensi sebesar 0,0053%. Adapun daya listrik yang dihasilkan mencapai 72,469 Kata Kunci : Konversi Energi, Elevated Solar Tower, Efisiensi Kolektor

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

    Science.gov (United States)

    Delta Vocational Technical School, Marked Tree, AR.

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

  20. Aeroelastic modelling of a Piezo-solar tensioned energy harvesting ribbon

    Science.gov (United States)

    Chatterjee, Punnag; Bryant, Matthew

    2016-04-01

    A multifunctional compliant structure is proposed that can harvest electrical power from both incident sunlight and ambient mechanical energy including wind flow or vibration. The proposed energy harvesting device consists of a slender, ribbon-like, flexible thin film solar cell that is laminated with piezoelectric patches at either ends and mounted in the cross flow of wind in a clamped-clamped end condition with an adjustable axial preload. Taking this motivation forward a system model of the energy harvester is developed which captures the structural response of the solar ribbon and couples it with Theodorsen unsteady aerodynamics to predict the flutter boundary conditions as a function of applied axial preload tension. The model also accounts for geometric and material discontinuities, by effective use of Transfer Matrix Method (TMM) modeling technique both in bending and torsional degrees of freedom. This paper also derives TMM technique for torsional vibrations with an applied axial load from first principles, verifies the method and presents its applicability for the proposed energy harvester. The paper also points out that the flutter instability arises out of different structural modes at different values applied axial tension, with the help of a sample modal convergence plot. The analysis also presents the possibility to tune the solar ribbon to operate at an optimal reduced frequency by adjusting the applied axial preload.

  1. Future: Solar energy. Zukunft: Sonnenenergie

    Energy Technology Data Exchange (ETDEWEB)

    Lange, V.

    1987-01-01

    The first chapter, 'Solar energy - more than just Utopia' deals with the following: Alternatives to nuclear energy problems of energy supply, solar energy use, commencement of the solar age in space, solar technology in the Federal Republic of Germany, solar collectors, wind power, energy from hydrogen. The second chapter 'Solar energy - its contribution to future energy supply' discusses prospects for the future (interviews with scientists and engineers). The third and last chapter gives practical hints (solar energy use: self-construction of solar plants). (HWJ).

  2. Simulating the Value of Concentrating Solar Power with Thermal Energy Storage in a Production Cost Model

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, P.; Hummon, M.

    2012-11-01

    Concentrating solar power (CSP) deployed with thermal energy storage (TES) provides a dispatchable source of renewable energy. The value of CSP with TES, as with other potential generation resources, needs to be established using traditional utility planning tools. Production cost models, which simulate the operation of grid, are often used to estimate the operational value of different generation mixes. CSP with TES has historically had limited analysis in commercial production simulations. This document describes the implementation of CSP with TES in a commercial production cost model. It also describes the simulation of grid operations with CSP in a test system consisting of two balancing areas located primarily in Colorado.

  3. Solar energy in Czechoslovakia

    OpenAIRE

    Lindberg, Eva

    1990-01-01

    The purpose of my tour to Czechoslovakia was to participate the Third International Conference Applied Optics in Solar Energy, which was held in Prague, Octoher 2-6, 1989, and then visit some scientific institutes and solar collector plants as guest of the Czechoslovakian Academy of Science. This was made possihle hy an exchange researcher grant from the Royal Swedish Academy of Engineering Sciences.

  4. The Energy Crisis and Solar Energy

    Science.gov (United States)

    Bockris, J. O'M.

    1974-01-01

    Examines the status of the energy crisis in Australia. Outlines energy alternatives for the 1990's and describes the present status of solar energy research and the economics of solar energy systems. (GS)

  5. The Energy Crisis and Solar Energy

    Science.gov (United States)

    Bockris, J. O'M.

    1974-01-01

    Examines the status of the energy crisis in Australia. Outlines energy alternatives for the 1990's and describes the present status of solar energy research and the economics of solar energy systems. (GS)

  6. Solar energy policy review

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-08-17

    A number of memoranda and reports are collected which deal with evaluations of solar energy policy options, including direct and indirect labor impacts and costs of different options and consumer protection. (LEW)

  7. Solar energy storage

    CERN Document Server

    Sorensen, Bent

    2015-01-01

    While solar is the fastest-growing energy source in the world, key concerns around solar power's inherent variability threaten to de-rail that scale-up . Currently, integration of intermittent solar resources into the grid creates added complication to load management, leading some utilities to reject it altogether, while other operators may penalize the producers via rate increases or force solar developers to include storage devices on-site to smooth out power delivery at the point of production. However these efforts at mitigation unfold, it is increasingly clear to parties on all sides th

  8. An Update of the Analytical Groundwater Modeling to Assess Water Resource Impacts at the Afton Solar Energy Zone

    Energy Technology Data Exchange (ETDEWEB)

    Quinn, John J. [Argonne National Lab. (ANL), Argonne, IL (United States); Greer, Christopher B. [Argonne National Lab. (ANL), Argonne, IL (United States); Carr, Adrianne E. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2014-10-01

    The purpose of this study is to update a one-dimensional analytical groundwater flow model to examine the influence of potential groundwater withdrawal in support of utility-scale solar energy development at the Afton Solar Energy Zone (SEZ) as a part of the Bureau of Land Management’s (BLM’s) Solar Energy Program. This report describes the modeling for assessing the drawdown associated with SEZ groundwater pumping rates for a 20-year duration considering three categories of water demand (high, medium, and low) based on technology-specific considerations. The 2012 modeling effort published in the Final Programmatic Environmental Impact Statement for Solar Energy Development in Six Southwestern States (Solar PEIS; BLM and DOE 2012) has been refined based on additional information described below in an expanded hydrogeologic discussion.

  9. Solar Energy: Solar System Design Fundamentals.

    Science.gov (United States)

    Knapp, Henry H., III

    This module on solar system design fundamentals is one of six in a series intended for use as supplements to currently available materials on solar energy and energy conservation. Together with the recommended texts and references (sources are identified), these modules provide an effective introduction to energy conservation and solar energy…

  10. Tehnical day: solar energy

    OpenAIRE

    Carli, Barbara

    2012-01-01

    This dissertation presents an example of planning and carrying out a technical activity day in the field of solar energy in primary school grades 7 and 9. Firstly, we briefly present technical activity days, the goals and criteria for the planning of technical days, and the topics and devices connected to the technical day in question and were needed in the execution of the experiments. We have selected four simple experiments in the field of solar energy and prepared the needed worksheets fo...

  11. Surface Meteorology and Solar Energy

    Data.gov (United States)

    National Aeronautics and Space Administration — Surface Meteorology and Solar Energy data - over 200 satellite-derived meteorology and solar energy parameters, monthly averaged from 22 years of data, global solar...

  12. Modeling and control of a small solar fuel cell hybrid energy system

    Institute of Scientific and Technical Information of China (English)

    LI Wei; ZHU Xin-jian; CAO Guang-yi

    2007-01-01

    This paper describes a solar photovoltaic fuel cell (PVEC) hybrid generation system consisting of a photovoltaic (PV) generator, a proton exchange membrane fuel cell (PEMFC), an electrolyser, a supercapacitor, a storage gas tank and power conditioning unit (PCU). The load is supplied from the PV generator with a fuel cell working in parallel. Excess PV energy when available is converted to hydrogen using an electrolyser for later use in the fuel cell. The individual mathematical model for each component is presented. Control strategy for the system is described. MATLAB/Simulink is used for the simulation of this highly nonlinear hybrid energy system. The simulation results are shown in the paper.

  13. Solar radiation models - review

    Directory of Open Access Journals (Sweden)

    M. Jamil Ahmad, G.N. Tiwari

    2010-05-01

    Full Text Available In the design and study of solar energy, information on solar radiation and its components at a given location is very essential. Solar radiation data are required by solar engineers, architects, agriculturists and hydrologists for many applications such as solar heating, cooking, drying and interior illumination of buildings. For this purpose, in the past, several empirical correlations have been developed in order to estimate the solar radiation around the world. The main objective of this study is to review the global solar radiation models available in the literature. There are several formulae which relate global radiation to other climatic parameters such as sunshine hours, relative humidity and maximum temperature. The most commonly used parameter for estimating global solar radiation is sunshine duration. Sunshine duration can be easily and reliably measured and data are widely available.

  14. Analysis of electronic models for solar cells including energy resolved defect densities

    Energy Technology Data Exchange (ETDEWEB)

    Glitzky, Annegret

    2010-07-01

    We introduce an electronic model for solar cells including energy resolved defect densities. The resulting drift-diffusion model corresponds to a generalized van Roosbroeck system with additional source terms coupled with ODEs containing space and energy as parameters for all defect densities. The system has to be considered in heterostructures and with mixed boundary conditions from device simulation. We give a weak formulation of the problem. If the boundary data and the sources are compatible with thermodynamic equilibrium the free energy along solutions decays monotonously. In other cases it may be increasing, but we estimate its growth. We establish boundedness and uniqueness results and prove the existence of a weak solution. This is done by considering a regularized problem, showing its solvability and the boundedness of its solutions independent of the regularization level. (orig.)

  15. Solar Energy Education. Renewable energy activities for earth science

    Energy Technology Data Exchange (ETDEWEB)

    1980-01-01

    A teaching manual is provided to aid teachers in introducing renewable energy topics to earth science students. The main emphasis is placed on solar energy. Activities for the student include a study of the greenhouse effect, solar gain for home heating, measuring solar radiation, and the construction of a model solar still to obtain fresh water. Instructions for the construction of apparatus to demonstrate a solar still, the greenhouse effect and measurement of the altitude and azimuth of the sun are included. (BCS)

  16. Modeling of heat transfer and energy analysis of potato slices and cylinders during solar drying

    Energy Technology Data Exchange (ETDEWEB)

    Tripathy, P.P. [Centre for Energy Studies, Indian Institute of Technology, Hauz Khas, New Delhi 110 016 (India); Kumar, Subodh [Centre for Energy Studies, Indian Institute of Technology, Hauz Khas, New Delhi 110 016 (India)], E-mail: subodh@ces.iitd.ernet.in

    2009-04-15

    In the present work, a method based on energy balance considering the effects of heat capacity of the food product, radiative heat transfer from food product to the drying chamber and solar radiation absorbed in the product during drying is proposed for determination of convective heat transfer coefficient, h{sub c}. A natural convection mixed-mode solar dryer is used for performing the experiments on potato cylinders and slices of same thickness of 0.01 m with respective length and diameter of 0.05 m. The present investigation indicates that the cylindrical samples exhibit higher values of h{sub c} and faster drying rate compared to those of slices, as expected. The h{sub c} values for each sample shape are correlated by an equation of the form Nu = C(Ra){sup n}. Laplace transform is applied to solve the proposed heat transfer diffusion model considering the effect of moisture transfer rate to predict the transient sample temperature. The model is validated through a close agreement between calculated and experimental results of transient sample temperature. Results of energy analysis reveal that for both the sample geometries, decreasing product moisture content during drying resulted in significant reduction in specific energy consumption. For almost similar drying conditions, a considerable amount of reduction in specific energy consumption is achieved for cylinders, as expected.

  17. A Model of Solar Energy Utilisation in the Anaerobic Digestion of Cattle Manure

    NARCIS (Netherlands)

    Mashad, El H.; Loon, van W.K.P.; Zeeman, G.

    2003-01-01

    The anaerobic digestion of cow manure has a higher destruction of pathogens and weed seeds under thermophilic conditions compared to mesophilic conditions. To maintain such conditions, solar energy can be used. In this research, the consequences of the use of solar energy under Egyptian conditions a

  18. Photovoltaic solar energy conversion

    CERN Document Server

    Bauer, Gottfried H

    2015-01-01

    This concise primer on photovoltaic solar energy conversion invites readers to reflect on the conversion of solar light into energy at the most fundamental level and encourages newcomers to the field to help find meaningful answers on how photovoltaic solar energy conversion can work (better), eventually contributing to its ongoing advancement. The book is based on lectures given to graduate students in the Physics Department at the University of Oldenburg over the last two decades, yet also provides an easy-to-follow introduction for doctoral and postdoctoral students from related disciplines such as the materials sciences and electrical engineering. Inspired by classic textbooks in the field, it reflects the author’s own ideas on how to understand, visualize and eventually teach the microscopic physical mechanisms and effects, while keeping the text as concise as possible so as to introduce interested readers to the field and balancing essential knowledge with open questions.

  19. A numerical model for charge transport and energy conversion of perovskite solar cells.

    Science.gov (United States)

    Zhou, Yecheng; Gray-Weale, Angus

    2016-02-14

    Based on the continuity equations and Poisson's equation, we developed a numerical model for perovskite solar cells. Due to different working mechanisms, the model for perovskite solar cells differs from that of silicon solar cells and Dye Sensitized Solar Cells. The output voltage and current are calculated differently, and in a manner suited in particular to perovskite organohalides. We report a test of our equations against experiment with good agreement. Using this numerical model, it was found that performances of solar cells increase with charge carrier's lifetimes, mobilities and diffusion lengths. The open circuit voltage (Voc) of a solar cell is dependent on light intensities, and charge carrier lifetimes. Diffusion length and light intensity determine the saturated current (Jsc). Additionally, three possible guidelines for the design and fabrication of perovskite solar cells are suggested by our calculations. Lastly, we argue that concentrator perovskite solar cells are promising.

  20. Solar energy conversion

    CERN Document Server

    Likhtenshtein, Gertz I

    2012-01-01

    Finally filling a gap in the literature for a text that also adopts the chemist?s view of this hot topic, Prof Likhtenshtein, an experienced author and internationally renowned scientist, considers different physical and engineering aspects in solar energy conversion. From theory to real-life systems, he shows exactly which chemical reactions take place when converting light energy, providing an overview of the chemical perspective from fundamentals to molecular harvesting systems and solar cells. This essential guide will thus help researchers in academia and industry better understa

  1. Surface meteorology and Solar Energy

    Science.gov (United States)

    Stackhouse, Paul W. (Principal Investigator)

    The Release 5.1 Surface meteorology and Solar Energy (SSE) data contains parameters formulated for assessing and designing renewable energy systems. Parameters fall under 11 categories including: Solar cooking, solar thermal applications, solar geometry, tilted solar panels, energy storage systems, surplus product storage systems, cloud information, temperature, wind, other meteorological factors, and supporting information. This latest release contains new parameters based on recommendations by the renewable energy industry and it is more accurate than previous releases. On-line plotting capabilities allow quick evaluation of potential renewable energy projects for any region of the world. The SSE data set is formulated from NASA satellite- and reanalysis-derived insolation and meteorological data for the 10-year period July 1983 through June 1993. Results are provided for 1 degree latitude by 1 degree longitude grid cells over the globe. Average daily and monthly measurements for 1195 World Radiation Data Centre ground sites are also available. [Mission Objectives] The SSE project contains insolation and meteorology data intended to aid in the development of renewable energy systems. Collaboration between SSE and technology industries such as the Hybrid Optimization Model for Electric Renewables ( HOMER ) may aid in designing electric power systems that employ some combination of wind turbines, photovoltaic panels, or diesel generators to produce electricity. [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=1993-06-30] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180].

  2. Solar energy hot water heating and electric utilities. A model validation

    Science.gov (United States)

    1981-10-01

    TRNSYS is a residential solar simulation program designed to provide detailed simulations of individual solar systems composed of almost any presently used residential solar technology. The model is described and a validation of the model is presented using a group of domestic solar hot water systems in the metropolitan Philadelphia area. The collection and reduction of the data used is discussed, and the TRNSYS modeling of the systems is presented. The model results are given and a sensitivity analysis of the models was performed to determine the effect of input changes on the electric auxiliary backup consumption.

  3. Solar Photovoltaic Energy.

    Science.gov (United States)

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

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

  4. Solar energy conversion

    OpenAIRE

    Crabtree, George W.; Lewis, Nathan S.

    2007-01-01

    If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience.

  5. Solar Photovoltaic Energy.

    Science.gov (United States)

    Ehrenreich, Henry; Martin, John H.

    1979-01-01

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

  6. An application of a multi model approach for solar energy prediction in Southern Italy

    Science.gov (United States)

    Avolio, Elenio; Lo Feudo, Teresa; Calidonna, Claudia Roberta; Contini, Daniele; Torcasio, Rosa Claudia; Tiriolo, Luca; Montesanti, Stefania; Transerici, Claudio; Federico, Stefano

    2015-04-01

    The accuracy of the short and medium range forecast of solar irradiance is very important for solar energy integration into the grid. This issue is particularly important for Southern Italy where a significant availability of solar energy is associated with a poor development of the grid. In this work we analyse the performance of two deterministic models for the prediction of surface temperature and short-wavelength radiance for two sites in southern Italy. Both parameters are needed to forecast the power production from solar power plants, so the performance of the forecast for these meteorological parameters is of paramount importance. The models considered in this work are the RAMS (Regional Atmospheric Modeling System) and the WRF (Weather Research and Forecasting Model) and they were run for the summer 2013 at 4 km horizontal resolution over Italy. The forecast lasts three days. Initial and dynamic boundary conditions are given by the 12 UTC deterministic forecast of the ECMWF-IFS (European Centre for Medium Weather Range Forecast - Integrated Forecasting System) model, and were available every 6 hours. Verification is given against two surface stations located in Southern Italy, Lamezia Terme and Lecce, and are based on hourly output of models forecast. Results for the whole period for temperature show a positive bias for the RAMS model and a negative bias for the WRF model. RMSE is between 1 and 2 °C for both models. Results for the whole period for the short-wavelength radiance show a positive bias for both models (about 30 W/m2 for both models) and a RMSE of 100 W/m2. To reduce the model errors, a statistical post-processing technique, i.e the multi-model, is adopted. In this approach the two model's outputs are weighted with an adequate set of weights computed for a training period. In general, the performance is improved by the application of the technique, and the RMSE is reduced by a sizeable fraction (i.e. larger than 10% of the initial RMSE

  7. Teaching Children to Value Solar Energy

    Science.gov (United States)

    Hugerat, Muhamad; Saker, Salem; Odeh, Saeed; Agbaria, Adnan

    2011-01-01

    In this educational initiative, we suggest to build a real model of solar village inside the school, which uses only solar energy. These educational initiatives emphasize the importance of energy for a technological society and the advantage of alternative energy sources. In this scientific educational initiative, the pupils in three elementary…

  8. Purdue Solar Energy Utilization Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Agrawal, Rakesh [Purdue

    2014-01-21

    The objective of this project is to establish and set-up a laboratory that will facilitate research and development of new low-cost and high-efficiency solar energy utilization technologies at Purdue University. The outcome will help spur the creation of solar energy start-up companies and eventually a solar energy industry in Indiana that can help fulfill the growing national demand for solar energy.

  9. Model of Yield Response of Corn to Plant Population and Absorption of Solar Energy

    Science.gov (United States)

    Overman, Allen R.; Scholtz, Richard V.

    2011-01-01

    Biomass yield of agronomic crops is influenced by a number of factors, including crop species, soil type, applied nutrients, water availability, and plant population. This article is focused on dependence of biomass yield (Mg ha−1 and g plant−1) on plant population (plants m−2). Analysis includes data from the literature for three independent studies with the warm-season annual corn (Zea mays L.) grown in the United States. Data are analyzed with a simple exponential mathematical model which contains two parameters, viz. Ym (Mg ha−1) for maximum yield at high plant population and c (m2 plant−1) for the population response coefficient. This analysis leads to a new parameter called characteristic plant population, xc = 1/c (plants m−2). The model is shown to describe the data rather well for the three field studies. In one study measurements were made of solar radiation at different positions in the plant canopy. The coefficient of absorption of solar energy was assumed to be the same as c and provided a physical basis for the exponential model. The three studies showed no definitive peak in yield with plant population, but generally exhibited asymptotic approach to maximum yield with increased plant population. Values of xc were very similar for the three field studies with the same crop species. PMID:21297960

  10. Model of yield response of corn to plant population and absorption of solar energy.

    Directory of Open Access Journals (Sweden)

    Allen R Overman

    Full Text Available Biomass yield of agronomic crops is influenced by a number of factors, including crop species, soil type, applied nutrients, water availability, and plant population. This article is focused on dependence of biomass yield (Mg ha(-1 and g plant(-1 on plant population (plants m(-2. Analysis includes data from the literature for three independent studies with the warm-season annual corn (Zea mays L. grown in the United States. Data are analyzed with a simple exponential mathematical model which contains two parameters, viz. Y(m (Mg ha(-1 for maximum yield at high plant population and c (m(2 plant(-1 for the population response coefficient. This analysis leads to a new parameter called characteristic plant population, x(c = 1/c (plants m(-2. The model is shown to describe the data rather well for the three field studies. In one study measurements were made of solar radiation at different positions in the plant canopy. The coefficient of absorption of solar energy was assumed to be the same as c and provided a physical basis for the exponential model. The three studies showed no definitive peak in yield with plant population, but generally exhibited asymptotic approach to maximum yield with increased plant population. Values of x(c were very similar for the three field studies with the same crop species.

  11. Modeling of the steam hydrolysis in a two-step process for hydrogen production by solar concentrated energy

    Science.gov (United States)

    Valle-Hernández, Julio; Romero-Paredes, Hernando; Pacheco-Reyes, Alejandro

    2017-06-01

    In this paper the simulation of the steam hydrolysis for hydrogen production through the decomposition of cerium oxide is presented. The thermochemical cycle for hydrogen production consists of the endothermic reduction of CeO2 to lower-valence cerium oxide, at high temperature, where concentrated solar energy is used as a source of heat; and of the subsequent steam hydrolysis of the resulting cerium oxide to produce hydrogen. The modeling of endothermic reduction step was presented at the Solar Paces 2015. This work shows the modeling of the exothermic step; the hydrolysis of the cerium oxide (III) to form H2 and the corresponding initial cerium oxide made at lower temperature inside the solar reactor. For this model, three sections of the pipe where the reaction occurs were considered; the steam water inlet, the porous medium and the hydrogen outlet produced. The mathematical model describes the fluid mechanics; mass and energy transfer occurring therein inside the tungsten pipe. Thermochemical process model was simulated in CFD. The results show a temperature distribution in the solar reaction pipe and allow obtaining the fluid dynamics and the heat transfer within the pipe. This work is part of the project "Solar Fuels and Industrial Processes" from the Mexican Center for Innovation in Solar Energy (CEMIE-Sol).

  12. 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.

  13. Modeling of a CeO2 thermochemistry reduction process for hydrogen production by solar concentrated energy

    Science.gov (United States)

    Valle-Hernández, Julio; Romero-Paredes, Hernando; Arancibia-Bulnes, Camilo A.; Villafan-Vidales, Heidi I.; Espinosa-Paredes, Gilberto

    2016-05-01

    In this paper the simulation of the thermal reduction for hydrogen production through the decomposition of cerium oxide is presented. The thermochemical cycle for hydrogen production consists of the endothermic reduction of CeO2 at high temperature, where concentrated solar energy is used as a source of heat; and of the subsequent steam hydrolysis of the resulting cerium oxide to produce hydrogen. For the thermochemical process, a solar reactor prototype is proposed; consisting of a cubic receptacle made of graphite fiber thermally insulated. Inside the reactor a pyramidal arrangement with nine tungsten pipes is housed. The pyramidal arrangement is made respect to the focal point where the reflected energy is concentrated. The solar energy is concentrated through the solar furnace of high radiative flux. The endothermic step is the reduction of the cerium oxide to lower-valence cerium oxide, at very high temperature. The exothermic step is the hydrolysis of the cerium oxide (III) to form H2 and the corresponding initial cerium oxide made at lower temperature inside the solar reactor. For the modeling, three sections of the pipe where the reaction occurs were considered; the carrier gas inlet, the porous medium and the reaction products outlet. The mathematical model describes the fluid mechanics; mass and energy transfer occurring therein inside the tungsten pipe. Thermochemical process model was simulated in CFD. The results show a temperature distribution in the solar reaction pipe and allow obtaining the fluid dynamics and the heat transfer within the pipe. This work is part of the project "Solar Fuels and Industrial Processes" from the Mexican Center for Innovation in Solar Energy (CEMIE-Sol).

  14. Solar energy to biofuels.

    Science.gov (United States)

    Agrawal, Rakesh; Singh, Navneet R

    2010-01-01

    In a solar economy, sustainably available biomass holds the potential to be an excellent nonfossil source of high energy density transportation fuel. However, if sustainably available biomass cannot supply the liquid fuel need for the entire transport sector, alternatives must be sought. This article reviews biomass to liquid fuel conversion processes that treat biomass primarily as a carbon source and boost liquid fuel production substantially by using supplementary energy that is recovered from solar energy at much higher efficiencies than the biomass itself. The need to develop technologies for an energy-efficient future sustainable transport sector infrastructure that will use different forms of energy, such as electricity, H(2), and heat, in a synergistic interaction with each other is emphasized. An enabling template for such a future transport infrastructure is presented. An advantage of the use of such a template is that it reduces the land area needed to propel an entire transport sector. Also, some solutions for the transition period that synergistically combine biomass with fossil fuels are briefly discussed.

  15. Modeling and Zoning Solar Energy Received at the Earth's Surface in Arid and Semiarid Regions of Central Iran

    Directory of Open Access Journals (Sweden)

    azam gholamnia

    2017-02-01

    Full Text Available Introduction: Solar radiation (Rs energy received at the Earth's surface is measured usingclimatological variables in horizontal surface and is widely used in various fields. Domination of hot and dry climates especially in the central regions of Iran results from decreasing cloudiness and precipitation and increasing sunshine hours, which shows the high potential of solar energy in Iran. There is a reasonable climatic field and solar radiation in most of regions and seasons which have provided an essential and suitable field to use and extend new and pure energy. Materials and Methods: One of the common methods to estimate the solar energy received by the earthis usingtemperature variables in any place . An empirical model is proposed to estimate the solar energy as a function of other climatic variables (maximum temperature recorded in 50 climatological, conventional stations; this model is helpful inextending the climatological solar-energy estimation in the study area. The mean values of both measured and estimated solar energy wereobjectively mapped to fill the observation gaps and reduce the noise associated with inhomogeneous statistics and estimation errors. This analysis and the solar irradiation estimation method wereapplied to 50 different climatologicalstations in Iran for monthly data during1980–2005. The main aim of this study wasto map and estimate the solar energy received in four provinces of Yazd, Esfahan, Kerman and Khorasan-e-Jonoubi.The data used in this analysis and its processing, as well as the formulation of an empirical model to estimate the climatological incident of solar energy as a function of other climatic variables, which is complemented with an objective mapping to obtain continuous solar-energy maps. Therefore, firstly the Rswasestimated using a valid model for 50 meteorological stations in which the amounts of solar radiation weren't recorded for arid and semi-arid areas in Iran. Then, the appropriate method

  16. Renewable Resources: a national catalog of model projects. Volume 1. Northeast Solar Energy Center Region

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Northeast Solar Energy Center Region. (WHK).

  17. Renewable Resources: a national catalog of model projects. Volume 3. Southern Solar Energy Center Region

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Southern Solar Energy Center Region. (WHK)

  18. Development, testing, and certification of Owens-Illinois model SEC-601 solar energy collector system

    Science.gov (United States)

    Parker, J. C.

    1979-01-01

    The final results are presented of the additional development work on the existing air-cooled solar energy collector subsystem for use with solar heating and cooling systems. The report discusses the intended use of the final report, describes the deliverable end items, lists program objectives, relates how they were accomplished, deals with problems encountered during fabrication and testing, and includes a certification statement of performance. The report shows that the products developed are marketable and suitable for public use.

  19. Solar energy applications in Nigeria

    Energy Technology Data Exchange (ETDEWEB)

    Ilenikhena, P.A.; Ezemonye, L.I.N.

    2010-09-15

    Solar radiation being abundantly present in Nigeria was one area of focus in renewable energy sources. Researches were carried out and technologies produced for direct harnessing of the energy in six energy centres across the country. Some state governments in collaboration with non-governmental agencies also sponsored solar energy projects in some villages that are not connected to the national grid.

  20. Summary of solar energy technology characterizations

    Energy Technology Data Exchange (ETDEWEB)

    D' Alessio, Dr., Gregory J.; Blaunstein, Dr., Robert R.

    1980-09-01

    This report summarizes the design, operating, energy, environmental, and economic characteristics of 38 model solar systems used in the Technology Assessment of Solar Energy Systems Project including solar heating and cooling of buildings, agricultural and industrial process heat, solar electric conversion, and industrial biomass systems. The generic systems designs utilized in this report were based on systems studies and mission analyses performed by the DOE National Laboratories and the MITRE Corporation. The purpose of those studies were to formulate materials and engineering cost data and performance data of solar equipment once mass produced.

  1. Photovoltaic Solar Energy Generation

    CERN Document Server

    Lotsch, H.K.V; U.Hoffmann, Volker; Rhodes, William T; Asakura, Toshimitsu; Brenner, Karl-Heinz; Hänsch, Theodor W; Kamiya, Takeshi; Krausz, Ferenc; Monemar, Bo; Venghaus, Herbert; Weber, Horst; Weinfurter, Harald

    2005-01-01

    This comprehensive description and discussion of photovoltaics (PV) is presented at a level that makes it accessible to the interested academic. Starting with an historical overview, the text outlines the relevance of photovoltaics today and in the future. Then follows an introduction to the physical background of solar cells and the most important materials and technologies, with particular emphasis placed on future developments and prospects. The book goes beyond technology by also describing the path from the cell to the module to the system, proceeding to important applications, such as grid-connected and stand-alone systems. The composition and development of the markets and the role of PV in future energy systems are also considered. Finally, the discussion turns to the future structure of energy supplies, expected to comprise more distributed generation, and addresses synergies and competition from other carbon-free energy sources.

  2. Modeling Feasibility of a Proposed Renewable Energy System with Wind and Solar Resources and Hydro Storage in Complex Terrain

    Science.gov (United States)

    Jiang, J.; Koracin, D.; Hamilton, R.; Hagen, D.; King, K. C.

    2012-04-01

    High temporal and spatial variability in wind and solar power brings difficulties in integrating these resources into an electricity grid. These difficulties are even more emphasized in areas with complex topography due to complicated flow patterns and cloudiness evolution. This study investigates the feasibility and efficiency of a proposed renewable energy system with wind and solar resources and hydro storages in western Nevada, U.S.A. The state-of-the-art Weather Research and Forecasting (WRF) model was used for the prediction of wind fields and incoming solar radiation at the ground surface. Forecast winds and solar radiation were evaluated with observational data from four wind masts and four meteorological towers in two months, July 2007 and January 2010. Based on a hypothetical wind farm and an assumed neighboring solar power plant both located near the hydro storage facility, as well as considering local power demand, the efficiency of the renewable energy system is projected. One of the main questions was how to optimize a schedule of activating pump storages according to the characteristics of several available hydro pumps, and wind and/or solar power predictions. The results show that segmentation of the pump-storage channel provides improved efficiency of the entire system. This modeled renewable energy system shows promise for possible applications and grid integration.

  3. Decentalized solar photovoltaic energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Krupka, M. C.

    1980-09-01

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

  4. Performance Modeling of Mimosa pudica Extract as a Sensitizer for Solar Energy Conversion

    Directory of Open Access Journals (Sweden)

    M. B. Shitta

    2016-01-01

    Full Text Available An organic material is proposed as a sustainable sensitizer and a replacement for the synthetic sensitizer in a dye-sensitized solar cell technology. Using the liquid extract from the leaf of a plant called Mimosa pudica (M. pudica as a sensitizer, the performance characteristics of the extract of M. pudica are investigated. The photo-anode of each of the solar cell sample is passivated with a self-assembly monolayer (SAM from a set of four materials, including alumina, formic acid, gelatine, and oxidized starch. Three sets of five samples of an M. pudica–based solar cell are produced, with the fifth sample used as the control experiment. Each of the solar cell samples has an active area of 0.3848cm2. A two-dimensional finite volume method (FVM is used to model the transport of ions within the monolayer of the solar cell. The performance of the experimentally fabricated solar cells compares qualitatively with the ones obtained from the literature and the simulated solar cells. The highest efficiency of 3% is obtained from the use of the extract as a sensitizer. It is anticipated that the comparison of the performance characteristics with further research on the concentration of M. pudica extract will enhance the development of a reliable and competitive organic solar cell. It is also recommended that further research should be carried out on the concentration of the extract and electrolyte used in this study for a possible improved performance of the cell.

  5. A model for predicting the potential diffusion of solar energy systems in complex urban environments

    Energy Technology Data Exchange (ETDEWEB)

    La Gennusa, Maria; Lascari, Giovanni; Rizzo, Gianfranco; Scaccianoce, Gianluca [Dipartimento dell' Energia, Universita degli Studi di Palermo, Viale delle Scienze - Building 9, 90128 Palermo (Italy); Sorrentino, Giancarlo, E-mail: sorrentino@dream.unipa.it [Dipartimento dell' Energia, Universita degli Studi di Palermo, Viale delle Scienze - Building 9, 90128 Palermo (Italy)

    2011-09-15

    The necessity to reduce greenhouse gases emission produced by energy building consumptions and to cut the energy bill (mainly due to the use of fossil sources) leads to the employment of renewable energy sources in new planned scenarios. In particular, more and more often municipal energy and environmental plans pay great attention to the possibilities of employment of the solar technologies at urban scale. Solar thermal and photovoltaic (PV) systems are, by far, the most suitable tools to be utilized in urban areas. Obviously, the proper adoption of such systems in buildings does call for the availability of calculation methods suitable to provide the actual level of exploitation of solar energy in urban layouts. In this work, a procedure for evaluating the geographical energy potential of building roofs in urban areas is proposed; in particular, the amount of surface on the roof that could be used for the installation of systems able to capture solar radiation for the energy production is investigated. The proposed procedure is based on the use of the GIS technology and 3D cartography. The effectiveness of the proposed method is assessed by means of an application to the town of Palermo (Italy). - Highlights: > The GIS techniques allow to analyze various future scenarios about urban planning. > We propose a procedure for assessing the extension of superficial urban areas useable for the installation of solar systems. > This procedure allow to compile a scale of priority of intervention. > The cost for financing such interventions is compared to the penalty to pay for not achieving the Kyoto goals.

  6. National Energy Act statutes and solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Howard, J.

    1980-02-01

    The National Energy Act of 1978 contains many provisions that will significantly affect solar technology commercialization and solar energy users. Four of the five statutes that comprise the National Energy Act deserve close attention. The National Energy Conservation Policy Act will promote residential solar installations. The Energy Tax Act will accelerate both residential and commercial solar system applications. The Public Utilities Regulatory Policies Act promotes efficient use of utility resources as well as decentralized power production. And, the Power Plan and Industrial Fuel Use Act places severe restrictions on future burning of petroleum and natural gas, which should lead some operators to build or convert to solar energy systems. Each of the preceding acts are considered in separate sections of this report. Federal regulations issued pursuant to the various provisions are also identified and discussed, and some of the problems with the provisions and regulations are noted.

  7. Support for solar energy collectors

    Science.gov (United States)

    Cole, Corey; Ardell-Smith, Zachary; Ciasulli, John; Jensen, Soren

    2016-11-01

    A solar energy collection system can include support devices configured to accommodate misalignment of components during assembly. For example, the system can include piles fixed to the earth and an adjustable bearing assembly at the upper end of the pile. The adjustable bearing assembly can include at least one of a vertical adjustment device, a lateral adjustment device and an angular adjustment device. The solar energy collection system can also include a plurality of solar energy collection device pre-wired together and mounted to a support member so as to form modular units. The system can also include enhanced supports for wire trays extending between rows of solar energy collection devices.

  8. Solar energy and environmental ethics

    Energy Technology Data Exchange (ETDEWEB)

    Geiger, C.J.

    1984-01-01

    Current directions in the scientific development and advocacy of solar technology emphasize its technical efficiency, its ability to function in place of conventional energy technologies, and measures of its long-run cost effectiveness. Those directions do not consider human experience or the effect of their preoccupation with technical thinking. Even environmental ethics, as it relates to solar energy, and legal aspects of the use of solar energy are biased toward finding fixed solutions to social problems. The German thinker Martin Heidegger argued that meaningful involvement in any saturation depends on one's ability to think clearly and thoroughly. Heidegger's emphasis on thinking and thoughtfulness fits best with ways of using solar energy that are appropriate to both the nature of solar energy and the lifestyles of the users. Truly appropriate use of solar energy requires what Heidegger called a composure toward solar technology, in which solar technology might change to suit new circumstances but not to the point where the user cannot control it. The horizons of solar technology itself are broadened in the context to include scientifically less-sophisticated equipment, and ways of using solar energy that reflect changes in lifestyle and greater awareness of the sun.

  9. Solar energy for the hospital?

    Science.gov (United States)

    1981-01-01

    You can't scrap your boiler and expect solar panels to provide steam for process and heating, but solar systems are cost-effective now for domestic hot water generation, according to a leading solar energy engineering/design/build firm.

  10. Solar energy technical training directory

    Energy Technology Data Exchange (ETDEWEB)

    Corcoleotes, G; Kramer, K; O& #x27; Connor, K

    1979-06-01

    Available solar energy offerings in the technical training area are presented. Institutions are listed alphabetically by state. Each listing includes an institution address and phone number, solar programs or curricula offered, and detailed solar couse information. An alphabetical index of institutions in included. (MHR)

  11. A solar energy controller

    Energy Technology Data Exchange (ETDEWEB)

    Laurentiu, A.

    1981-05-30

    A simplified design of a flat solar energy collector with an absorber made from plastic, and a housing stamped from polyethylene with a thermal insulation layer made from porous plastic is patented. The thermal insulation layer is also stamped out as a hole part in the necessary shape. A transparency made from transparent plastic in the form of a cover is applied to the housing. The cover has edges that attach to the vertical walls of the housing. In order to improve the seal of the internal area of the collector, the edges of the transparency fit into the gap between the vertical walls of the housing and the attachment piece on the walls. The collector is characterized by simplicity in assembly and low cost.

  12. Hydrogen production from solar energy

    Science.gov (United States)

    Eisenstadt, M. M.; Cox, K. E.

    1975-01-01

    Three alternatives for hydrogen production from solar energy have been analyzed on both efficiency and economic grounds. The analysis shows that the alternative using solar energy followed by thermochemical decomposition of water to produce hydrogen is the optimum one. The other schemes considered were the direct conversion of solar energy to electricity by silicon cells and water electrolysis, and the use of solar energy to power a vapor cycle followed by electrical generation and electrolysis. The capital cost of hydrogen via the thermochemical alternative was estimated at $575/kW of hydrogen output or $3.15/million Btu. Although this cost appears high when compared with hydrogen from other primary energy sources or from fossil fuel, environmental and social costs which favor solar energy may prove this scheme feasible in the future.

  13. 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.

  14. Computational modelling of panchromatic porphyrins with strong NIR absorptions for solar energy capture

    Science.gov (United States)

    Agnihotri, Neha

    2016-11-01

    Five potential push-pull porphyrin dyes (PR1-PR5) substituted with extended rylene anhydride units (n = 1-5) as electron acceptors and (4-dimethylamino) phenyl ethynylene as an electron donor have been investigated computationally using density functional theory and time dependent-density functional theory. Their molecular orbital energies are reported together with their singlet and triplet electronic transition energies, oscillator strengths and charge transfer characteristics. These sensitizers are panchromatic, their fully-allowed charge transfer transitions extend well into the near infrared and their HOMO and LUMO energies appear well-matched to the band gap and electrochemical potential requirements of dye-sensitized solar cells (DSSCs).

  15. Advanced Methods for Incorporating Solar Energy Technologies into Electric Sector Capacity-Expansion Models: Literature Review and Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sullivan, P.; Eurek, K.; Margolis, R.

    2014-07-01

    Because solar power is a rapidly growing component of the electricity system, robust representations of solar technologies should be included in capacity-expansion models. This is a challenge because modeling the electricity system--and, in particular, modeling solar integration within that system--is a complex endeavor. This report highlights the major challenges of incorporating solar technologies into capacity-expansion models and shows examples of how specific models address those challenges. These challenges include modeling non-dispatchable technologies, determining which solar technologies to model, choosing a spatial resolution, incorporating a solar resource assessment, and accounting for solar generation variability and uncertainty.

  16. Photovoltaic solar energy; Energia solar fotovoltaica

    Energy Technology Data Exchange (ETDEWEB)

    Fraidenraich, Naum; Tiba, Chigueru; Vilela, Olga de Castro; Barbosa, Elielza Moura de Souza [Universidade Federal de Pernambuco(UFPE), Recife, PE (Brazil). Dept. de Energia Nuclear (DEN). Grupo de Pesquisas em Fontes Alternativas de Energia

    2003-07-01

    This chapter gives an overview on energy generation from thermal solar energy, analysing the international markets of the photovoltaic modules, the changes which are being produced in the application character, the environmental phenomena resulting from the modules production, briefly describes the physical phenomena explaining the photovoltaic effect, analyses the process of module price formation and performs the energy costs resultant for the user and subsides politics being practiced in various countries.

  17. Estimating Roof Solar Energy Potential in the Downtown Area Using a GPU-Accelerated Solar Radiation Model and Airborne LiDAR Data

    OpenAIRE

    Yan Huang; Zuoqi Chen; Bin Wu; Liang Chen; Weiqing Mao; Feng Zhao; Jianping Wu; Junhan Wu; Bailang Yu

    2015-01-01

    Solar energy, as a clean and renewable resource is becoming increasingly important in the global context of climate change and energy crisis. Utilization of solar energy in urban areas is of great importance in urban energy planning, environmental conservation, and sustainable development. However, available spaces for solar panel installation in cities are quite limited except for building roofs. Furthermore, complex urban 3D morphology greatly affects sunlit patterns on building roofs, espe...

  18. Solar energy perspectives for public power

    Energy Technology Data Exchange (ETDEWEB)

    Woodley, N. H.

    1979-06-01

    Perspectives on the utilization of solar energy for electricity production and thermal energy utilization by the public are briefly discussed. Wind energy conversion, biomass conversion, solar thermal, OTEC, photovoltaics, and solar heating and cooling are discussed. (WHK)

  19. Modeling and simulation of a solar power source at 3kW for a clean energy without pollution

    Directory of Open Access Journals (Sweden)

    Louzazni M.

    2014-04-01

    Full Text Available The air pollution was much worse, and it became necessary to replace the fossil energy sources by the renewable energies. The causes are related to reserves that can be exhausted, to pollution and their impacts on the environment. Production of toxic gases from the combustion of coal for the effect of increasing the temperature of the earth. Solar energy is a clean and inexhaustible excellent alternative. We propose a modeling and simulation of a solar system consists of a photovoltaic generator (PVG, a boost chopper, to supply a telecommunications relay station (BTS, According to the load characteristics (I = 60A, V = 48V DC (3 kW. A stage adaptation composed of this chopper controlled by a PWM controller (Pulse Width Modulation is used to control the optimal operating point (MPPT and optimize system performance using Matlab / Simulink.

  20. Modeling the efficiency of Förster resonant energy transfer from energy relay dyes in dye-sensitized solar cells

    KAUST Repository

    Hoke, Eric T.

    2010-02-11

    Förster resonant energy transfer can improve the spectral breadth, absorption and energy conversion efficiency of dye sensitized solar cells. In this design, unattached relay dyes absorb the high energy photons and transfer the excitation to sensitizing dye molecules by Förster resonant energy transfer. We use an analytic theory to calculate the excitation transfer efficiency from the relay dye to the sensitizing dye accounting for dynamic quenching and relay dye diffusion. We present calculations for pores of cylindrical and spherical geometry and examine the effects of the Förster radius, the pore size, sensitizing dye surface concentration, collisional quenching rate, and relay dye lifetime. We find that the excitation transfer efficiency can easily exceed 90% for appropriately chosen dyes and propose two different strategies for selecting dyes to achieve record power conversion efficiencies. © 2010 Optical Society of America.

  1. A hydrogen-solar energy model for the Brazil: energy demand forecasting and economical aspects; Um modelo a hidrogenio-solar para o Brasil: projecoes de demanda de energia e aspectos economicos

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Samuel N.M. de [Univesidade Estadual de Campins (UNICAMP), SP (Brazil). Dept. de Energia; Lima, Lutero C. de; Mendes, Nathan [Uberlandia Univ., MG (Brazil). Dept. de Engenharia Mecanica

    1994-07-01

    This study proposes the introduction of hydrogen-solar renewable and clean fuel for replacing the present fossil fuels. The hydrogen can be produced by electric energy from using photovoltaic cells. The Brazil can be considered a suitable country for this system due to the high insulation in various areas of the country. Forecast for total energy demand, fossil energy, hydrogen prices and total cost of the project is performed by using mathematical modelling.

  2. Technical use of solar energy: Conversion from solar to thermal energy, solar cooling and thermal energy storage

    Science.gov (United States)

    Arafa, A.; Fisch, N.; Hahne, E.; Kraus, K.; Seemann, D.; Seifert, B.; Sohns, J.; Schetter, G.; Schweigerer, W.

    1983-12-01

    Experimental and theoretical studies in the field of solar energy utilization are reviewed. Specific topics considered are: flat plate water collectors, solar absorbers, air collectors, solar absorption cooling, solar simulators, aquifiers, latent heat stores, and space heating systems.

  3. Coupled thermal fluid modelling of a low embedded energy solar thermal collector

    Energy Technology Data Exchange (ETDEWEB)

    Corcoran, M.; Gibbons, C. [Cork Institute of Technology (Ireland). Energy Engineering Group

    2004-07-01

    A mathematical model was developed for a forced convection solar hot water system. The solar collector in this study incorporates a honeycombed extruded polycarbonate structure, for both the cover and water channels. The initial section of the program predicts solar radiation (hourly, monthly and yearly) as an input section to the solar collector calculations. As well as determining the collector performance, the model also facilitates changes to the collector physical properties such as dimensions of the channels, selective and non-selective absorbers, material thermal properties, as well as ambient temperature and flow rate, in order to optimise the system design. The results from the program will allow a full parametric study of different collector design criteria, with this polycarbonate structure. The results will be compared to a standard flat plate collector design, to see if this polycarbonate flat plate collector is a more effective design. ISO 9806-2 standards are being used to validate the results, for the parametric study in the lab, under steady state conditions. The final optimum design will then be tested outdoors using the quasi-dynamic conditions set out by the European Standard EN 12975-2. Weather data, obtained from the weather station set up at CIT, will be used as the input for the weather conditions for out door testing. (orig.)

  4. Solar energy: principles and possibilities.

    Science.gov (United States)

    Rhodes, Christopher J

    2010-01-01

    As the world faces an impending dearth of fossil fuels, most immediately oil, alternative sources of energy must be found. 174 PW worth of energy falls onto the top of the Earth's atmosphere in the form of sunlight which is almost 10,000 times the total amount of energy used by humans on Earth, as taken from all sources, oil, coal, natural gas, nuclear and hydroelectric power combined. If even a fraction of this could be harvested efficiently, the energy crunch could in principle be averted. Various means for garnering energy from the Sun are presented, including photovoltaics (PV), thin film solar cells, quantum dot cells, concentrating PV and thermal solar power stations, which are more efficient in practical terms. Finally the prospects of space based (satellite) solar power are considered. The caveat is that even if the entire world electricity budget could be met using solar energy, the remaining 80% of energy which is not used as electricity but thermal power (heat) still needs to be found in the absence of fossil fuels. Most pressingly, the decline of cheap plentiful crude oil (peak oil) will not find a substitution via solar unless a mainly electrified transportation system is devised and it is debatable that there is sufficient time and conventional energy remaining to accomplish this. The inevitable contraction of transportation will default a deconstruction of the globalised world economy into that of a system of localised communities.

  5. Chemistry of Personalized Solar Energy

    Science.gov (United States)

    Nocera, Daniel G.

    2012-01-01

    Personalized energy (PE) is a transformative idea that provides a new modality for the planet’s energy future. By providing solar energy to the individual, an energy supply becomes secure and available to people of both legacy and non-legacy worlds, and minimally contributes to increasing the anthropogenic level of carbon dioxide. Because PE will be possible only if solar energy is available 24 hours a day, 7 day a week, the key enabler for solar PE is an inexpensive storage mechanism. HX (X = halide or OH−) splitting is a fuel-forming reaction of sufficient energy density for large scale solar storage but the reaction relies on chemical transformations that are not understood at the most basic science level. Critical among these are multielectron transfers that are proton-coupled and involve the activation of bonds in energy poor substrates. The chemistry of these three italicized areas is developed, and from this platform, discovery paths leading to new HX and H2O splitting catalysts are delineated. For the case of the water splitting catalyst, it captures many of the functional elements of photosynthesis. In doing so, a highly manufacturable and inexpensive method has been discovered for solar PE storage. PMID:19775081

  6. Nanomaterials for solar energy

    KAUST Repository

    Revaprasadu, Neerish

    2013-01-01

    Nanostructured metal chalcogenides of the elements copper, iron, tin, lead and cadmium have attracted interest in their use as colloidal nanocrystal inks for solar cells. Some of these materials have the advantages of being available in abundance and having low toxicity. Developing methods for the combination of the elements to produce binary, ternary and quaternary compounds has dominated research in the field. This chapter will provide the most recent developments (from year 2012 onwards) for the synthesis and use of colloidal nanocrystal inks for solar cell applications. © The Royal Society of Chemistry 2014.

  7. Coronal energy input and dissipation in a solar active region 3D MHD model

    CERN Document Server

    Bourdin, Philippe-A; Peter, Hardi

    2015-01-01

    Context. We have conducted a 3D MHD simulation of the solar corona above an active region in full scale and high resolution, which shows coronal loops, and plasma flows within them, similar to observations. Aims. We want to find the connection between the photospheric energy input by field-line braiding with the coronal energy conversion by Ohmic dissipation of induced currents. Methods. To this end we compare the coronal energy input and dissipation within our simulation domain above different fields of view, e.g. for a small loops system in the active region (AR) core. We also choose an ensemble of field lines to compare, e.g., the magnetic energy input to the heating per particle along these field lines. Results. We find an enhanced Ohmic dissipation of currents in the corona above areas that also have enhanced upwards-directed Poynting flux. These regions coincide with the regions where hot coronal loops within the AR core are observed. The coronal density plays a role in estimating the coronal temperatur...

  8. Renewable energy forecasts for solar applications : an Environment Canada perspective

    Energy Technology Data Exchange (ETDEWEB)

    Poulin, L. [Environment Canada, Montreal, PQ (Canada). Meteorological Service of Canada

    2006-07-01

    The Meteorological Service of Canada has made weather datasets available in real-time on the Internet, for use by those with an interest in solar applications. Ensemble weather models can be used to produce medium range forecasts of weather events and to predict the likely available kilowatt-hours (kWhrs) of solar energy. As such, solar sites can maximize their harvest and use of solar energy. This presentation highlighted several different types of renewable energy forecasts obtained from weather models, including forecasts of expected kWhrs from solar panels and wind turbines, daily forecasts of expected solar heated water volumes and forecasts of water collection potential from impending precipitation events. The value of renewable energy forecasts in helping the solar energy sector monitor daily energy loads as well as daily and weekly solar energy supply was emphasized. It was suggested that renewable energy forecasts could raise public awareness of the potential of solar energy applications and help promote the solar energy market. Vendors of solar technology can also use the forecasts to help customers harmonize predicted solar energy coming to their sites with daily energy use patterns. figs.

  9. Photochemical conversion of solar energy.

    Science.gov (United States)

    Balzani, Vincenzo; Credi, Alberto; Venturi, Margherita

    2008-01-01

    Energy is the most important issue of the 21st century. About 85% of our energy comes from fossil fuels, a finite resource unevenly distributed beneath the Earth's surface. Reserves of fossil fuels are progressively decreasing, and their continued use produces harmful effects such as pollution that threatens human health and greenhouse gases associated with global warming. Prompt global action to solve the energy crisis is therefore needed. To pursue such an action, we are urged to save energy and to use energy in more efficient ways, but we are also forced to find alternative energy sources, the most convenient of which is solar energy for several reasons. The sun continuously provides the Earth with a huge amount of energy, fairly distributed all over the world. Its enormous potential as a clean, abundant, and economical energy source, however, cannot be exploited unless it is converted into useful forms of energy. This Review starts with a brief description of the mechanism at the basis of the natural photosynthesis and, then, reports the results obtained so far in the field of photochemical conversion of solar energy. The "grand challenge" for chemists is to find a convenient means for artificial conversion of solar energy into fuels. If chemists succeed to create an artificial photosynthetic process, "... life and civilization will continue as long as the sun shines!", as the Italian scientist Giacomo Ciamician forecast almost one hundred years ago.

  10. Dynamic Modeling and Simulation of a Thermoelectric-Solar Hybrid Energy System Using an Inverse Dynamic Analysis Input Shaper

    Directory of Open Access Journals (Sweden)

    A. M. Yusop

    2014-01-01

    Full Text Available This study presents the behavioral model of thermal temperature and power generation of a thermoelectric-solar hybrid energy system exposed to dynamic transient sources. In the development of thermoelectric-solar hybrid energy system, studies have focused on the regulation of both systems separately. In practice, a separate control system affects hardware pricing. In this study, an inverse dynamic analysis shaping technique based on exponential function is applied to a solar array (SA to stabilize output voltage before this technique is combined with a thermoelectric module (TEM. This method can be used to estimate the maximum power point of the hybrid system by initially shaping the input voltage of SA. The behavior of the overall system can be estimated by controlling the behavior of SA, such that SA can follow the output voltage of TEM as the time constant of TEM is greater than that of SA. Moreover, by employing a continuous and differentiable function, the acquired output behavior of the hybrid system can be attained. Data showing the model is obtained from current experiments with predicted values of temperature, internal resistance, and current attributes of TEM. The simulation results show that the proposed input shaper can be used to trigger the output voltage of SA to follow the TEM behavior under transient conditions.

  11. The Coronal Global Evolutionary Model (CGEM): Using HMI Vector Magnetogram and Doppler Data to Model the Buildup of Free Magnetic Energy in the Solar Corona

    CERN Document Server

    Fisher, George H; Bercik, David J; Kazachenko, Maria D; Lynch, Benjamin J; Welsch, Brian T; Hoeksema, J Todd; Hayashi, Keiji; Liu, Yang; Norton, Aimee A; Dalda, Alberto Sainz; Sun, Xudong; DeRosa, Marc L; Cheung, Mark C M

    2015-01-01

    The most violent space weather events (eruptive solar flares and coronal mass ejections) are driven by the release of free magnetic energy stored in the solar corona. Energy can build up on timescales of hours to days, and then may be suddenly released in the form of a magnetic eruption, which then propagates through interplanetary space, possibly impacting the Earth's space environment. Can we use the observed evolution of the magnetic and velocity fields in the solar photosphere to model the evolution of the overlying solar coronal field, including the storage and release of magnetic energy in such eruptions? The objective of CGEM, the Coronal Global Evolutionary Model, funded by the NASA/NSF Space Weather Modeling program, is to develop and evaluate such a model for the evolution of the coronal magnetic field. The evolving coronal magnetic field can then be used as a starting point for magnetohydrodynamic (MHD) models of the corona, which can then be used to drive models of heliospheric evolution and predi...

  12. The Coronal Global Evolutionary Model: Using HMI Vector Magnetogram and Doppler Data to Model the Buildup of Free Magnetic Energy in the Solar Corona

    Science.gov (United States)

    Fisher, G. H.; Abbett, W. P.; Bercik, D. J.; Kazachenko, M. D.; Lynch, B. J.; Welsch, B. T.; Hoeksema, J. T.; Hayashi, K.; Liu, Y.; Norton, A. A.; Dalda, A. Sainz; Sun, X.; DeRosa, M. L.; Cheung, M. C. M.

    2015-06-01

    The most violent space weather events (eruptive solar flares and coronal mass ejections) are driven by the release of free magnetic energy stored in the solar corona. Energy can build up on timescales of hours to days, and then may be suddenly released in the form of a magnetic eruption, which then propagates through interplanetary space, possibly impacting the Earth's space environment. Can we use the observed evolution of the magnetic and velocity fields in the solar photosphere to model the evolution of the overlying solar coronal field, including the storage and release of magnetic energy in such eruptions? The objective of CGEM, the Coronal Global Evolutionary Model, funded by the NASA/NSF Space Weather Modeling program, is to develop and evaluate such a model for the evolution of the coronal magnetic field. The evolving coronal magnetic field can then be used as a starting point for magnetohydrodynamic (MHD) models of the corona, which can then be used to drive models of heliospheric evolution and predictions of magnetic field and plasma density conditions at 1AU.

  13. The necessity of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Lovejoy, D.

    1996-09-01

    The idea of limits to growth has, understandably, achieved notoriety since the days of Malthus and, more recently, the Club of Rome. However, there must be some limits to the ability of the Earth to sustain a growing population. Fortunately, population models suggest that the world`s population will probably level out at about two to three times the present numbers over the next hundred years. The question is whether the Earth`s resources are sufficient to sustain that population at a high standard of living for all. In this the key issue is energy. It is clear that present trends in energy consumption, especially oil, cannot be sustained much longer. Regardless of this, however, prudence demands a drastic reduction in fossil fuel consumption, in view of the possibility of global warming. It can be shown that, combined with greatly improved energy efficiency, a transition to a solar (renewable) energy based economy capable of sustaining the anticipated growth in the world economy, is possible, but the constraints are extremely tight. (Author)

  14. Energy balance in the solar transition region. I - Hydrostatic thermal models with ambipolar diffusion

    Science.gov (United States)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1990-01-01

    The energy balance in the lower transition region is analyzed by constructing theoretical models which satisfy the energy balance constraint. The energy balance is achieved by balancing the radiative losses and the energy flowing downward from the corona. This energy flow is mainly in two forms: conductive heat flow and hydrogen ionization energy flow due to ambipolar diffusion. Hydrostatic equilibrium is assumed, and, in a first calculation, local mechanical heating and Joule heating are ignored. In a second model, some mechanical heating compatible with chromospheric energy-balance calculations is introduced. The models are computed for a partial non-LTE approach in which radiation departs strongly from LTE but particles depart from Maxwellian distributions only to first order. The results, which apply to cases where the magnetic field is either absent, or uniform and vertical, are compared with the observed Lyman lines and continuum from the average quiet sun. The approximate agreement suggests that this type of model can roughly explain the observed intensities in a physically meaningful way, assuming only a few free parameters specified as chromospheric boundary conditions.

  15. Integrated solar energy system optimization

    Science.gov (United States)

    Young, S. K.

    1982-11-01

    The computer program SYSOPT, intended as a tool for optimizing the subsystem sizing, performance, and economics of integrated wind and solar energy systems, is presented. The modular structure of the methodology additionally allows simulations when the solar subsystems are combined with conventional technologies, e.g., a utility grid. Hourly energy/mass flow balances are computed for interconnection points, yielding optimized sizing and time-dependent operation of various subsystems. The program requires meteorological data, such as insolation, diurnal and seasonal variations, and wind speed at the hub height of a wind turbine, all of which can be taken from simulations like the TRNSYS program. Examples are provided for optimization of a solar-powered (wind turbine and parabolic trough-Rankine generator) desalinization plant, and a design analysis for a solar powered greenhouse.

  16. A solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Vasilyev, L.L.; Avakyan, Yu V.; Dabagyan, T.N.; Grakovich, L.P.; Khustalev, D.K.; Morgun, V.A.; Vartanyan, A.V.

    1984-01-01

    During collector operation, solar emission is absorbed by the evaporator section of the heating tube; the degree of blackness of the forward wall of the section is increased significantly by the use of corrugations in this section. Boiling of the working fluid in the longitudinal slotted channels is accompanied by outbursts of the steam fluid mixture in the direction of the forward wall, resulting in wetting of the longitudinal corrugation on this wall. In this solar collector, there is a continuous flow of the working fluid onto the internal surface of the leading wall of the evaporation section of the heat tube; the working fluid evaporation process is accelerated by the spraying resulting from the popping of vapor bubbles.

  17. Energy balance in the solar transition region. III - Helium emission in hydrostatic, constant-abundance models with diffusion

    Science.gov (United States)

    Fontenla, J. M.; Avrett, E. H.; Loeser, R.

    1993-01-01

    In our previous papers we described the mathematical formalism and the computed results for energy-balance hydrostatic models of the solar transition region. In this paper we discuss in some detail the limitations of the hydrostatic and one-dimensional assumptions used. Then we analyze the determination of helium emission when diffusion is included. We use transport coefficients estimated from kinetic theory to determine the helium departures from local ionization balance. We calculate the helium spectra for each of our models and evaluate the role of helium in the energy transport. Also, we investigate the effects of coronal illumination on the structure of the transition region and upper chromosphere, and show how coronal illumination affects various EUV lines and the He I 10830 A line. Comparing with both absolute intensities and detailed line profiles, we show that our models are consistent not only with the observed hydrogen spectra but also with the available helium spectra.

  18. Statistical cloud coverage as determined from sunshine duration: a model applicable in daylighting and solar energy forecasting

    Science.gov (United States)

    Kómar, Ladislav; Kocifaj, Miroslav

    2016-12-01

    A radiative/luminous energy budget is difficult to predict on a daily or hourly base if cloud coverage is obtained by subjective methods in discrete time points. A simple theoretical model that overcomes this shortcoming through interrelation of absolute cloud fraction and sunshine duration is presented. The latter is measured routinely at the meteorological stations worldwide. The model is based on statistical probability of clear line of sight, where Poisson spatial cloud distribution is analyzed for three different cloud shapes. A validation of the model using long-term measurements show a good correlation between experimentally determined and theoretically predicted data. The absolute cloud fraction obtained this way are a base for daylighting and solar energy applications including simulations of luminance/radiance sky distributions under different meteorological conditions. A simple calculation tool is developed and demonstrated on global horizontal illuminance (GHI).

  19. Modeling particle acceleration and transport during high-energy solar gamma-ray events: Results from the HESPERIA project

    Science.gov (United States)

    Afanasiev, Alexandr; Battarbee, Markus; Vainio, Rami; Rouillard, Alexis; Aran, Angels; Sipola, Robert; Pomoell, Jens

    2016-04-01

    The EU/H2020 project "High Energy Solar Particle Events foRecastIng and Analysis" (HESPERIA) has an objective to gain improved understanding of solar energetic particle (SEP) acceleration, release and transport related to long-duration gamma-ray emissions recently observed by Fermi/LAT. We have performed simulation studies for particle acceleration and transport for the 17 May 2012 event, which is also a Ground Level Enhancement (GLE) of solar cosmic rays. The particle event is modeled assuming that it is accelerated by the shock wave driven by the erupting coronal mass ejection (CME). We first analyze the 3-dimensional propagation of the shock through the corona using imaging observations from SDO, SOHO and STEREO spacecraft. The derived kinematics of the shock is combined with magnetohydrodynamic and potential field modeling of the ambient corona to derive the evolution of the shock parameters on a large set of field lines. We then employ the self-consistent Coronal Shock Acceleration (CSA) simulation model of the University of Turku to study the acceleration process on selected field lines and combine it with a new model of downstream particle transport to assess the energy spectrum and time profile of accelerated particles precipitating in the dense surface regions below the corona. We also employ the Shock and Particle (SaP) simulation model of the University of Barcelona to analyze the interplanetary counterpart of the Fermi event. In this paper, we will present the observations of the event, our approach to the modeling and the first results of the analysis. The work has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 637324 (HESPERIA).

  20. Solar energy program. Annual report, 1978

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-02-01

    this annual report describes the work done at Argonne National Laboratory on the Solar Energy Program during FY 1978 (July 1, 1977 to June 30, 1978). Areas included in this report are solar energy collection, heating and cooling, thermal energy storage, ocean thermal energy conversion, photovoltaics, satellite power systems, bioconversion, central receiver solar thermal power, and wind energy conversion.

  1. Solar Energy-An Everyday Occurrence

    Science.gov (United States)

    Keister, Carole; Cornell, Lu Beth

    1978-01-01

    Describes a solar energy research project sponsored by the Energy Research and Development Administration and conducted at Timonium School in Maryland. Elementary student involvement in solar energy studies resulting from the project is noted. (MDR)

  2. Solar Energy-An Everyday Occurrence

    Science.gov (United States)

    Keister, Carole; Cornell, Lu Beth

    1978-01-01

    Describes a solar energy research project sponsored by the Energy Research and Development Administration and conducted at Timonium School in Maryland. Elementary student involvement in solar energy studies resulting from the project is noted. (MDR)

  3. Photovoltaic Solar Energy Generation

    Science.gov (United States)

    Goetzberger, Adolf; Hoffmann, Volker U.

    This comprehensive description and discussion of photovoltaics (PV) is presented at a level that makes it accessible to the interested academic. Starting with an historical overview, the text outlines the relevance of photovoltaics today and in the future. Then follows an introduction to the physical background of solar cells and the most important materials and technologies, with particular emphasis placed on future developments and prospects. The book goes beyond technology by also describing the path from the cell to the module to the system, proceeding to important applications such as grid-connected and stand-alone systems.

  4. Solar energy engineering processes and systems

    CERN Document Server

    Kalogirou, Soteris A

    2013-01-01

    As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

  5. Solar energy engineering processes and systems

    CERN Document Server

    Kalogirou, Soteris A

    2009-01-01

    As perhaps the most promising of all the renewable energy sources available today, solar energy is becoming increasingly important in the drive to achieve energy independence and climate balance. This new book is the masterwork from world-renowned expert Dr. Soteris Kalogirou, who has championed solar energy for decades. The book includes all areas of solar energy engineering, from the fundamentals to the highest level of current research. The author includes pivotal subjects such as solar collectors, solar water heating, solar space heating and cooling, industrial process heat, solar desalina

  6. Uncertainty analysis of a model of an energy distribution system with solar panel generation by Time-Varying Data Analysis, Monte Carlo Simulation and Fuzzy Interval Analysis

    OpenAIRE

    Ferrario, Elisa; Pini, Alessia

    2013-01-01

    International audience; The uncertainties in the model of an energy distribution system made of a solar panel, a storage energy system and loads (power demanded by the end-users) are investigated, treating the epistemic variables as possibilistic and the aleatory ones as probabilistic. In particular, time-varying probabilistic distributions of the solar irradiation and the power demanded by the end-users is inferred from historical data. Then a computational framework for the joint propagatio...

  7. Short review on solar energy systems

    Science.gov (United States)

    Herez, Amal; Ramadan, Mohamad; Abdulhay, Bakri; Khaled, Mahmoud

    2016-07-01

    Solar energy can be utilized mainly in heat generation and electricity production. International energy agency (IEA) shows, in a comparative study on the world energy consumption that in 2050 solar arrays installation will provide about 45% of world energy demand. Solar energy is one of the most important renewable energy source which plays a great role in providing energy solutions. As known there is wide variety of types of collectors and applications of solar energy. This paper aimed to make a short review on solar energy systems, according to types of collectors and applications used.

  8. Solar Energy for Rural Egypt

    Science.gov (United States)

    Abdelsalam, Tarek I.; Darwish, Ziad; Hatem, Tarek M.

    Egypt is currently experiencing the symptoms of an energy crisis, such as electricity outage and high deficit, due to increasing rates of fossil fuels consumption. Conversely, Egypt has a high solar availability of more than 18.5 MJ daily. Additionally, Egypt has large uninhabited deserts on both sides of the Nile valley and Sinai Peninsula, which both represent more than 96.5 % of the nation's total land area. Therefore, solar energy is one of the promising solutions for the energy shortage in Egypt. Furthermore, these vast lands are advantageous for commissioning large-scaled solar power projects, not only in terms of space availability, but also of availability of high quality silicon (sand) required for manufacturing silicon wafers used in photovoltaic (PV) modules. Also, rural Egypt is considered market a gap for investors, due to low local competition, and numerous remote areas that are not connected to the national electricity grid. Nevertheless, there are some obstacles that hinder the progress of solar energy in Egypt; for instance, the lack of local manufacturing capabilities, security, and turbulent market in addition to other challenges. This paper exhibits an experience of the authors designing and installing decentralized PV solar systems, with a total rated power of about 11 kW, installed at two rural villages in at the suburbs of Fayoum city, in addition to a conceptual design of a utility scale, 2 MW, PV power plant to be installed in Kuraymat. The outcomes of this experience asserted that solar PV systems can be a more technically and economically feasible solution for the energy problem in rural villages.

  9. Energy Storage and Release through the Solar Activity Cycle Models Meet Radio Observations

    CERN Document Server

    Nindos, Alexander

    2012-01-01

    For nearly sixty years, radio observations have provided a unique insight into the physics of the active and quiescent solar atmosphere. Thanks to the variety of emission mechanisms and to the large altitude range available to observations, fundamental plasma parameters have been measured from the low chromosphere to the upper corona and interplanetary medium. This book presents current research in solar radio astronomy and shows how well it fits in the exceptional scientific context brought by the current space solar observatories. It essentially contains contributed research and review papers presented during the 2010 Community of European Solar Radio Astronomers (CESRA) meeting, which took place in Belgium in June 2010. This book is aimed at graduate students and researchers working in solar physics and space science. Previously published in Solar Physics journal, Vol. 273/2, 2011.

  10. Solar energy and substainable development

    Science.gov (United States)

    Roux, Maria Carmen; Nalin, Olivier

    2010-05-01

    At the dawn of the 21st century, the world population doesn't stop rising. More than ever, energy and environment problems remain at the heart of our society concerns. What will we leave to the future generations ? Therefore, a twenty pupil class of 4e (13 and 14 year old pupils) has made a specific work about this topic, called "solar power and sustainable development". Initially, the pupils participated to the settlement of a meteorological station on the school grounds. This station, which provides readings about temperature, relative humidity, rainfall, sun radiations, wind power and wind heading is fed by photovoltaic cells and thus works independently. The pupils have then come to realize the ecological and practical interests of such a functioning (e.g. : for the latter : neither batteries nor electrical wires are needed). These past few years, in Provence (a highly sunny region), many solar panel installations have been created and many private house roofs have been equipped with photovoltaic cells. Indeed, this energy presents some significant assets : it is free, clean and will never run out. The village of Vinon sur Verdon, where stands our college, is partly fed by a solar panel park, located a few kilometers away. Strongly sensitive to the assets of this energy source, the pupils have made a poster asserting the benefits of solar power. Another side of solar energy has been asserted : the output of hot sanitary water. They have built a miniature on this topic. In order to be thorough, some elements remain in shadow, such as environment impacts done by the making, the transport and the recycling of solar panels that will be brought up in a collaboration with research establishments.

  11. 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...

  12. Food dehydration by solar energy.

    Science.gov (United States)

    Bolin, H R; Salunkhe, D K

    1982-01-01

    Solar driers that are currently being investigated for drying of agricultural products can be divided into two major divisions, depending upon how they transfer the incident solar energy to the product to be dried. These two divisions are direct and indirect drying, with some work also being done on combination drying procedures. In direct solar driers, the product to be dried is usually either inside a tent, greenhouse, or a glass-topped box, where the product to be dried is heated by the direct rays from the sun and the moist air is removed by ambient wind movement. These dryers do accelerate moisture loss rate and the product is usually safe from inclement weather. These dryers usually do not require fans for forced air circulation. With indirect drying, the opposite is true, where most require powered fans for forced air circulation. With this type of dryer, both flatplate and inflated tube solar heat absorbers are used, with each offering certain advantages. Also, combination dryers have been built that utilize both direct and indirect principles. Product evaluation of solar dried foods indicate that in most cases the physical properties, flavor, and vitamin A and C retention were as good as, or better than, conventional dried foods. The economics of the solar systems indicate that most drying procedures are economically feasible for use in small-scale operations only, with the exception of grain drying.

  13. Numerical simulation of flare energy build-up and release via Joule dissipation. [solar MHD model

    Science.gov (United States)

    Wu, S. T.; Bao, J. J.; Wang, J. F.

    1986-01-01

    A new numerical MHD model is developed to study the evolution of an active region due to photospheric converging motion, which leads to magnetic-energy buildup in the form of electric current. Because this new MHD model has incorporated finite conductivity, the energy conversion occurs from magnetic mode to thermal mode through Joule dissipation. In order to test the causality relationship between the occurrence of flare and photospheric motion, a multiple-pole configuration with neutral point is used. Using these results it is found that in addition to the converging motion, the initial magnetic-field configuration and the redistribution of the magnetic flux at photospheric level enhance the possibility for the development of a flare.

  14. A simple model for the energy supply of a stand-alone house using a hybrid wind-solar power system

    Science.gov (United States)

    Beke, Tamas

    2016-01-01

    A research project for secondary school students involving both physical measurements and modelling is presented. The problem to be solved is whether and how a typical house can be supplied with energy off-grid, based entirely on renewable energy sources, more specifically, on solar and wind energy, while using relatively simple devices, namely, photovoltaic modules, wind turbines and accumulators. To this end our students carried out a long term measurement series in order to assess the typical energy consumption of houses. Further, the number of solar modules and wind turbines, and the necessary accumulator capacity, was estimated.

  15. Solar energy and the aeronautics industry. Thesis

    Science.gov (United States)

    Benedek, L.

    1985-01-01

    An introduction to the physical aspects of solar energy, incidental energy and variations in solar flux is presented, along with an explanation of the physical principles of obtaining solar energy. The history of the application of solar energy to aeronautics, including the Gossamer Penguin and the Solar Challenger is given. Finally, an analysis of the possibilities of using a reaction motor with hybrid propulsion combining solar energy with traditional fuels as well as calculations of the proposed cycle and its mode of operation are given.

  16. Solar wind-magnetosphere energy input functions

    Energy Technology Data Exchange (ETDEWEB)

    Bargatze, L.F.; McPherron, R.L.; Baker, D.N.

    1985-01-01

    A new formula for the solar wind-magnetosphere energy input parameter, P/sub i/, is sought by applying the constraints imposed by dimensional analysis. Applying these constraints yields a general equation for P/sub i/ which is equal to rho V/sup 3/l/sub CF//sup 2/F(M/sub A/,theta) where, rho V/sup 3/ is the solar wind kinetic energy density and l/sub CF//sup 2/ is the scale size of the magnetosphere's effective energy ''collection'' region. The function F which depends on M/sub A/, the Alfven Mach number, and on theta, the interplanetary magnetic field clock angle is included in the general equation for P/sub i/ in order to model the magnetohydrodynamic processes which are responsible for solar wind-magnetosphere energy transfer. By assuming the form of the function F, it is possible to further constrain the formula for P/sub i/. This is accomplished by using solar wind data, geomagnetic activity indices, and simple statistical methods. It is found that P/sub i/ is proportional to (rho V/sup 2/)/sup 1/6/VBG(theta) where, rho V/sup 2/ is the solar wind dynamic pressure and VBG(theta) is a rectified version of the solar wind motional electric field. Furthermore, it is found that G(theta), the gating function which modulates the energy input to the magnetosphere, is well represented by a ''leaky'' rectifier function such as sin/sup 4/(theta/2). This function allows for enhanced energy input when the interplanetary magnetic field is oriented southward. This function also allows for some energy input when the interplanetary magnetic field is oriented northward. 9 refs., 4 figs.

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

    Science.gov (United States)

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

    2015-09-01

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

  18. Modeling of solar polygeneration plant

    Science.gov (United States)

    Leiva, Roberto; Escobar, Rodrigo; Cardemil, José

    2017-06-01

    In this work, a exergoeconomic analysis of the joint production of electricity, fresh water, cooling and process heat for a simulated concentrated solar power (CSP) based on parabolic trough collector (PTC) with thermal energy storage (TES) and backup energy system (BS), a multi-effect distillation (MED) module, a refrigeration absorption module, and process heat module is carried out. Polygeneration plant is simulated in northern Chile in Crucero with a yearly total DNI of 3,389 kWh/m2/year. The methodology includes designing and modeling a polygeneration plant and applying exergoeconomic evaluations and calculating levelized cost. Solar polygeneration plant is simulated hourly, in a typical meteorological year, for different solar multiple and hour of storage. This study reveals that the total exergy cost rate of products (sum of exergy cost rate of electricity, water, cooling and heat process) is an alternative method to optimize a solar polygeneration plant.

  19. Estimating Solar Energy Potential in Buildings on a Global Level

    DEFF Research Database (Denmark)

    Petrichenko, Ksenia

    2015-01-01

    This chapter contributes to the debate around net-zero energy concept from a global perspective. By means of comprehensive modelling, it analyses how much global building energy consumption could be reduced through utilisation of building-integrated solar energy technologies and energy......-efficiency improvements. Valuable insights on the locations and building types, in which it is feasible to achieve a net-zero level of energy performance through solar energy utilisation, are presented in world maps....

  20. Comparative evaluation of solar, fission, fusion, and fossil energy resources. Part 1: Solar energy

    Science.gov (United States)

    Williams, J. R.

    1974-01-01

    The utilization of solar energy to meet the energy needs of the U.S. is discussed. Topics discussed include: availability of solar energy, solar energy collectors, heating for houses and buildings, solar water heater, electric power generation, and ocean thermal power.

  1. Error Assessment of Solar Irradiance Forecasts and AC Power from Energy Conversion Model in Grid-Connected Photovoltaic Systems

    Directory of Open Access Journals (Sweden)

    Gianfranco Chicco

    2015-12-01

    Full Text Available Availability of effective estimation of the power profiles of photovoltaic systems is essential for studying how to increase the share of intermittent renewable sources in the electricity mix of many countries. For this purpose, weather forecasts, together with historical data of the meteorological quantities, provide fundamental information. The weak point of the forecasts depends on variable sky conditions, when the clouds successively cover and uncover the solar disc. This causes remarkable positive and negative variations in the irradiance pattern measured at the photovoltaic (PV site location. This paper starts from 1 to 3 days-ahead solar irradiance forecasts available during one year, with a few points for each day. These forecasts are interpolated to obtain more irradiance estimations per day. The estimated irradiance data are used to classify the sky conditions into clear, variable or cloudy. The results are compared with the outcomes of the same classification carried out with the irradiance measured in meteorological stations at two real PV sites. The occurrence of irradiance spikes in “broken cloud” conditions is identified and discussed. From the measured irradiance, the Alternating Current (AC power injected into the grid at two PV sites is estimated by using a PV energy conversion model. The AC power errors resulting from the PV model with respect to on-site AC power measurements are shown and discussed.

  2. Projections of long-term changes in solar radiation based on CMIP5 climate models and their influence on energy yields of photovoltaic systems

    Science.gov (United States)

    Wild, Martin; Folini, Doris; Henschel, Florian; Müller, Björn

    2015-04-01

    Traditionally, for the planning and assessment of solar energy systems, the amount of solar radiation (sunlight) incident on the Earth's surface is assumed to be constant over the years. However, with changing climate and air pollution levels, solar resources may no longer be stable over time and undergo substantial decadal changes. Observational records covering the past decades confirm long-term changes in this quantity. Here we examine, how the latest generation of climate models used for the 5th IPCC report projects potential changes in surface solar radiation over the coming decades, and how this may affect, in combination with the expected greenhouse warming, solar power output from photovoltaic (PV) systems. For this purpose, projections up to the mid 21th century from 39 state of the art climate models from the Coupled Model Intercomparison Project Phase 5 (CMIP5) are analysed globally and for selected key regions with major solar power production capacity. The large model ensemble allows to assess the degree of consistency of their projections. Models are largely consistent in the sign of the projected changes in solar radiation under cloud-free conditions as well as in surface temperatures over most of the globe, while still reasonably consistent over a considerable part of the globe in the sign of changes in cloudiness and associated changes in solar radiation. A first order estimate of the impact of solar radiation and temperature changes on energy yields of PV systems under the RPC8.5 scenario indicates statistically significant decreases in PV outputs in large parts of the world, but notable exceptions with positive trends in parts of Europe and the South-East of China. Projected changes between 2006 and 2049 under the RCP8.5 scenario overall are on the order of 1 % per decade for horizontal planes, but may be larger for tilted or tracked planes as well as on shorter (decadal) timescales. Related References: Wild, M., Folini, D., Henschel, F., and M

  3. Solar Energy Education. Industrial arts: student activities. Field test edition

    Energy Technology Data Exchange (ETDEWEB)

    1981-02-01

    In this teaching manual several activities are presented to introduce students to information on solar energy through classroom instruction. Wind power is also included. Instructions for constructing demonstration models for passive solar systems, photovoltaic cells, solar collectors and water heaters, and a bicycle wheel wind turbine are provided. (BCS)

  4. Solar insolation model

    Science.gov (United States)

    Smith, J. H.

    1980-01-01

    Computer program SOLINS helps engineers with relatively complex task of choosing best orientation of fixed flat-plate solar collectors for local conditions. Program models average hourly solar insolation on fixed but arbitrarily-oriented surface. Consideration is given to problems of array spacing, shadowing, and use of augmentation reflectors to increase insolation at collector surface.

  5. Solar energy in buildings: Implications for California energy policy

    Science.gov (United States)

    Hirshberg, A. S.; Davis, E. S.

    1977-01-01

    An assessment of the potential of active solar energy systems for buildings in California is summarized. The technology used for solar heating, cooling, and water heating in buildings is discussed. The major California weather zones and the solar energy designs are described, as well as the sizing of solar energy systems and their performance. The cost of solar energy systems is given both at current prices and at prices consistent with optimistic estimates for the cost of collectors. The main institutional barriers to the wide spread use of solar energy are summarized.

  6. Solar energy – new photovoltaic technologies

    DEFF Research Database (Denmark)

    Sommer-Larsen, Peter

    2009-01-01

    of its major energy sources. Solar energy is a focus point in many strategies for a sustainable energy supply. The European Commission’s Strategic Energy Plan (SET-plan) envisages a Solar Europe Initiative, where photovoltaics and concentrated solar power (CSP) supply as much power as wind mills......Solar energy technologies directly convert sunlight into electricity and heat, or power chemical reactions that convert simple molecules into synthetic chemicals and fuels. The sun is by far the most abundant source of energy, and a sustainable society will need to rely on solar energy as one...... in the future. Much focus is directed towards photovoltaics presently. Installation of solar cell occurs at an unprecedented pace and the expectations of the photovoltaics industry are high: a total PV capacity of 40 GW by 2012 as reported by a recent study. The talk progresses from general solar energy topics...

  7. Solar energy – new photovoltaic technologies

    DEFF Research Database (Denmark)

    Sommer-Larsen, Peter

    2009-01-01

    Solar energy technologies directly convert sunlight into electricity and heat, or power chemical reactions that convert simple molecules into synthetic chemicals and fuels. The sun is by far the most abundant source of energy, and a sustainable society will need to rely on solar energy as one...... of its major energy sources. Solar energy is a focus point in many strategies for a sustainable energy supply. The European Commission’s Strategic Energy Plan (SET-plan) envisages a Solar Europe Initiative, where photovoltaics and concentrated solar power (CSP) supply as much power as wind mills...... in the future. Much focus is directed towards photovoltaics presently. Installation of solar cell occurs at an unprecedented pace and the expectations of the photovoltaics industry are high: a total PV capacity of 40 GW by 2012 as reported by a recent study. The talk progresses from general solar energy topics...

  8. Solar Energy Forecast System Development and Implementation

    Science.gov (United States)

    Jascourt, S. D.; Kirk-Davidoff, D. B.; Cassidy, C.

    2012-12-01

    Forecast systems for predicting real-time solar energy generation are being developed along similar lines to those of more established wind forecast systems, but the challenges and constraints are different. Clouds and aerosols play a large role, and for tilted photovoltaic panels and solar concentrating plants, the direct beam irradiance, which typically has much larger forecast errors than global horizontal irradiance, must be utilized. At MDA Information Systems, we are developing a forecast system based on first principles, with the well-validated REST2 clear sky model (Gueymard, 2008) at its backbone. In tuning the model and addressing aerosol scattering and surface albedo, etc., we relied upon the wealth of public data sources including AERONET (aerosol optical depth at different wavelengths), Suominet (GPS integrated water vapor), NREL MIDC solar monitoring stations, SURFRAD (includes upwelling shortwave), and MODIS (albedo in different wavelength bands), among others. The forecast itself utilizes a blend of NWP model output, which must be brought down to finer time resolution based on the diurnal cycle rather than simple interpolation. Many models currently do not output the direct beam irradiance, and one that does appears to have a bias relative to its global horizontal irradiance, with equally good performance attained by utilizing REST2 and the model global radiation to estimate the direct component. We will present a detailed assessment of various NWP solar energy products, evaluating forecast skill at a range of photovoltaic installations.

  9. Renewable Resources: a national catalog of model projects. Volume 2. Mid-American Solar Energy Complex Region

    Energy Technology Data Exchange (ETDEWEB)

    None

    1980-07-01

    This compilation of diverse conservation and renewable energy projects across the United States was prepared through the enthusiastic participation of solar and alternate energy groups from every state and region. Compiled and edited by the Center for Renewable Resources, these projects reflect many levels of innovation and technical expertise. In many cases, a critique analysis is presented of how projects performed and of the institutional conditions associated with their success or failure. Some 2000 projects are included in this compilation; most have worked, some have not. Information about all is presented to aid learning from these experiences. The four volumes in this set are arranged in state sections by geographic region, coinciding with the four Regional Solar Energy Centers. The table of contents is organized by project category so that maximum cross-referencing may be obtained. This volume includes information on the Mid-American Solar Energy Complex Region. (WHK)

  10. Solar energy sciences and engineering applications

    CERN Document Server

    Enteria, Napoleon

    2013-01-01

    Solar energy is available all over the world in different intensities. Theoretically, the solar energy available on the surface of the earth is enough to support the energy requirements of the entire planet. However, in reality, progress and development of solar science and technology depends to a large extent on human desires and needs. This is due to the various barriers to overcome and to deal with the economics of practical utilization of solar energy.This book will introduce the rapid development and progress in the field of solar energy applications for science and technology: the advanc

  11. Wuestite - a solar energy carrier

    Energy Technology Data Exchange (ETDEWEB)

    Weidenkaff, A.; Nueesch, P.; Wokaun, A. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Reller, A. [Hamburg Univ., Hamburg (Germany)

    1997-06-01

    Hydrogen is produced when Wuestite (Fe{sub 1-y}O) is oxidised by water. This reaction is part of a two-step thermochemical metal oxide cycle for the storage of solar energy in the form of chemical energy carriers, characterised by a high chemical potential. The reaction was studied in a tubular furnace with on-line gas analysis and further characterised in detail by DTA und high-temperature X-ray powder diffraction. The influence of non-stoichiometry, morphology and temperature on the mechanism and kinetics of the water-splitting reaction was determined. (author) 3 figs., tabs., 3 refs.

  12. Internalizing the externalities of solar technology: Methodologies for incorporating externalities in the assessment of policy options and technology assessments of solar energy initiatives and R and D programs using Brookhaven models

    Energy Technology Data Exchange (ETDEWEB)

    Marcuse, W

    1978-05-01

    Internalizing the costs for implementing solar energy may never be, the author says. In the meantime, budget allocation decisions must be made. It is the purpose of this paper to identify capabilities currently in existence at BNL that help to provide answers to the value of increasing the contribution of solar energy. This paper presents several alternative approaches. BNL models that are useful for the economic measurement of energy related environmental damage are NEDS/REPS1 NEDS/REPS; ESNS; PRESTO; and optimization models (M-RESOM, BECOM, SOGEPH, BESOM, DESOM/TESOM/MARICAL). The approaches suggested would be much more useful if they were evaluated by certain criteria. This is the goal of most systems research on internalizing externalities. The methods described provide quantitative measures for the following criteria, although no single method provides all of them: the residuals produced with and without solar; the impact of residuals on life, property, ecosystems, and ambience; the intergenerational effects; the effect of oil imports on security; the depletion of non-renewable resources; the quantification (as far as possible) of externalities; and the appropriate level of aggregration. In most cases in this paper, examples are given. The most common criteria is that the energy demands must be driven by an economic model that in turn is driven by an energy model that produces the energy prices and the fuel mix. Solar technology implementation is particularly dependent on relative prices, economic activity, and energy demand. (MCW)

  13. Modeling the cooperative energy transfer dynamics of quantum cutting for solar cells

    NARCIS (Netherlands)

    Rabouw, Freddy T.; Meijerink, Andries

    2015-01-01

    Cooperative energy transfer (ET) is a quantum cutting (or downconversion) process where a luminescent center splits its excited state energy in two by simultaneous transfer to two nearby acceptor centers, thus yielding two low-energy photons for each high-energy photon absorbed. It has the potential

  14. Solar Energy Education. Renewable energy: a background text. [Includes glossary

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Some of the most common forms of renewable energy are presented in this textbook for students. The topics include solar energy, wind power hydroelectric power, biomass ocean thermal energy, and tidal and geothermal energy. The main emphasis of the text is on the sun and the solar energy that it yields. Discussions on the sun's composition and the relationship between the earth, sun and atmosphere are provided. Insolation, active and passive solar systems, and solar collectors are the subtopics included under solar energy. (BCS)

  15. Modeling of Solar Concentrators

    Science.gov (United States)

    Rockey, D. E.

    1984-01-01

    Algorithm developed for predicting power output, uniformity of intensity and operating temperature of concentrator-enhanced photovoltaic solar cell arrays. Optimum values for parameters such as reflector geometry found prior to constructing scale models for testing.

  16. CURRENT TRENDS IN THE USE OF SOLAR ENERGY

    Directory of Open Access Journals (Sweden)

    Vanya Zhivkova

    2013-06-01

    Full Text Available Solar energy represents the amount of solar radiation per unit time on unit area. Solar energy is used to obtain thermal energy through solar, and electrical energy through exist for solar energy: passive and active. The utilization of solar energy is essential for the development of human civilization.

  17. Energy Conversion: Nano Solar Cell

    Science.gov (United States)

    Yahaya, Muhammad; Yap, Chi Chin; Mat Salleh, Muhamad

    2009-09-01

    Problems of fossil-fuel-induced climate change have sparked a demand for sustainable energy supply for all sectors of economy. Most laboratories continue to search for new materials and new technique to generate clean energy at affordable cost. Nanotechnology can play a major role in solving the energy problem. The prospect for solar energy using Si-based technology is not encouraging. Si photovoltaics can produce electricity at 20-30 c//kWhr with about 25% efficiency. Nanoparticles have a strong capacity to absorb light and generate more electrons for current as discovered in the recent work of organic and dye-sensitized cell. Using cheap preparation technique such as screen-printing and self-assembly growth, organic cells shows a strong potential for commercialization. Thin Films research group at National University Malaysia has been actively involved in these areas, and in this seminar, we will present a review works on nanomaterials for solar cells and particularly on hybrid organic solar cell based on ZnO nanorod arrays. The organic layer consisting of poly[2-methoxy-5-(2-ethylhexyloxy)-1, 4-phenylenevinylene] (MEHPPV) and [6, 6]-phenyl C61-butyric acid 3-ethylthiophene ester (PCBE) was spin-coated on ZnO nanorod arrays. ZnO nanorod arrays were grown on FTO glass substrates which were pre-coated with ZnO nanoparticles using a low temperature chemical solution method. A gold electrode was used as the top contact. The device gave a short circuit current density of 2.49×10-4 mA/cm2 and an open circuit voltage of 0.45 V under illumination of a projector halogen light at 100 mW/cm2.

  18. Solar-energy storage-systems analysis

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, R W

    1981-04-01

    Systems analysis activities at Brookhaven National Laboratory (BNL) related to energy storage in solar applications are described, and the purpose, methods and, where available, the results of each study are summarized. Areas of investigation include storage of electrical and thermal energy in solar total energy systems, a theoretical investigation of the value of storage, and the national fuel displacement potential of semi-passive solar storage walls. Investigations of the cost effectiveness of a spectrum of passive solar storage devices and the value of several possible improvements in these devices constitutes BNL's contribution to the Solar Applications Analysis for Energy Storage (SAAES) project.

  19. Modeling and numerical simulation of a novel solar-powered absorption air conditioning system driven by a bubble pump with energy storage

    Institute of Scientific and Technical Information of China (English)

    QIU Jia; LIANG Jian; CHEN GuangMing; DU RuXu

    2009-01-01

    This paper presents a novel solar-powered absorption air conditioning system driven by a bubble pump with energy storage. It solves the problem of unreliable solar energy supply by storing the working fluids and hence, functions 24 h per day. First, the working principles are described and the dynamic models for the primary energy storage components are developed. Then, the system is evaluated based on a numerical simulation. Based on the meteorological data of a typical day in a subtropical area, with the area of a solar collector being set at 19.15 m2, whilst the initial charging mass, mass fraction and temperature of the solution are respectively set at 379.5 kg, 54.16% and 34.5 ℃, it is found that the respective coefficients of performance (COP) of the air conditioning system and the en-tire system (including the solar panel) are 0.7771 and 0.4372. In particular, the energy storage density of the system is 206.69 MJ/m3 which is much greater than those of chilled water or hot water storage systems under comparable conditions. This makes the new system much more compact and efficient. Finally, an automatic control strategy is given to achieve the highest COP when solar energy fluctuates.

  20. Mobil Solar Energy Corporation thin EFG octagons

    Science.gov (United States)

    Kalejs, J. P.

    1994-06-01

    Mobil Solar Energy Corporation manufactures photovoltaic modules based on its unique Edge-defined Film-fed Growth (EFG) process for producing octagon-shaped hollow polycrystalline silicon tubes. The octagons are cut by lasers into 100 mm x 100 mm wafers which are suitable for solar cell processing. This process avoids slicing, grinding and polishing operations which are wasteful of material and are typical of most other wafer production methods. EFG wafers are fabricated into solar cells and modules using processes that have been specially developed to allow scaling up to high throughput rates. The goals of the Photovoltaic Manufacturing Technology Initiative (PVMaT) program at Mobil Solar were to improve the EFG manufacturing line through technology advances that accelerate cost reduction in production and stimulate market growth for its product. The program was structured into three main tasks: to decrease silicon utilization by lowering wafer thickness from 400 to 200 (mu)m; to enhance laser cutting yields and throughput while improving the wafer strength; and to raise crystal growth productivity and yield. The technical problems faced and the advances made in the Mobil Solar PVMaT program are described. The author concludes with a presentation of the results of a detailed cost model for EFT module production. This model describes the accelerated reductions in manufacturing costs which are already in place and the future benefits anticipated to result from the technical achievements of the PVMaT program.

  1. Using experiments and demographic models to assess rare plant vulnerability to utlity-scale solar energy development

    Science.gov (United States)

    Moore, K. A.

    2015-12-01

    Pressing challenges for the implementation of solar energy are the effects of construction and operation on protected animal and plant species. Siting and mitigation of solar energy often requires understanding of basic biology and distributions of rare species that are unknown. How can we rapidly collect the information necessary on species- and site-specific population dynamics to effectively design mitigation and conservation measures? We have developed an integrated approach to assessing the vulnerability of a suite of representative rare plant species in the region. We implemented a prioritized series of demographic and experimental studies over the past four years to identify the types of species, populations, and life stages most vulnerable to impact or prone to conservation efforts. We have found substantial variation in vegetative and sexual reproduction between study populations for several rare plants, including between populations that vary in putative impact by development and/or effects of experimental solar arrays. For a subset of species, we designed population viability analysis and applied them to identify sensitive vital rates and compare quasi-extinction probabilities under different climate and impact scenarios. By utilizing practical experiments to test for the effects of real or simulated impacts, we found differences in vital rates between natural and disturbed populations adjacent to and within solar installations. We draw conclusions from our work to guide the analysis of benefits, permitting, and design of utility-scale solar energy facilities.

  2. Employment impacts of solar energy in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Cetin, Muejgan, E-mail: mujgan@sistemyon.com.tr [SISTEM Yoenetim Danismanligi Ltd. Sti. Atatuerk Cad. Ulastirici sok. Eris Sitesi A Blok No:3/7 Sahrayicedid-Erenkoey Istanbul (Turkey); Egrican, Niluefer [Suntek International Orhangazi Cad. No:54/A Dragos- Istanbul (Turkey)

    2011-11-15

    Solar energy is considered a key source for the future, not only for Turkey, also for all of the world. Therefore the development and usage of solar energy technologies are increasingly becoming vital for sustainable economic development. The main objective of this study is investigating the employment effects of solar energy industry in Turkey. Some independent reports and studies, which analyze the economic and employment impacts of solar energy industry in the world have been reviewed. A wide range of methods have been used in those studies in order to calculate and to predict the employment effects. Using the capacity targets of the photovoltaic (PV) and concentrated solar power (CSP) plants in the solar Roadmap of Turkey, the prediction of the direct and indirect employment impacts to Turkey's economy is possible. As a result, solar energy in Turkey would be the primary source of energy demand and would have a big employment effects on the economics. That can only be achieved with the support of governmental feed-in tariff policies of solar energy and by increasing research-development funds. - Highlights: > The objective of the study, is investigating employment effects of solar energy. > Using the capacity targets of the PV and CSP plants in solar roadmap of Turkey. > Direct employment has been calculated by constructing of the solar power plant. > If multiplier effect is accepted as 2, total employment will be doubled. > Validity of the figures depends on the government's policies.

  3. Introductory guide to solar energy

    CSIR Research Space (South Africa)

    Cawood, WN

    1976-01-01

    Full Text Available an extra tank to pre-heat the water supplied to the geyser. Solar water heaters can also be added to a system where an appliance such as a solid fuel stove or gas water heater is employed, with a useful saving in fuel. The following diagrams illustrate... were imminent. From what was said earlier it is obvious that the sun must eventually supply most of the earth's energy needs. In several parts of the world hot air engines that take their heat from the sun are in use to drive water pumps. One...

  4. Improving Air Quality with Solar Energy

    Science.gov (United States)

    2008-04-01

    This fact sheet series highlights how renewable energy and energy efficiency technologies can and are being used to reduce air emissions and meet environmental goals, showcasing case studies and technology-specific topics. This one focus on solar energy technologies.

  5. Non-ionizing energy loss calculations for modeling electron-induced degradation of Cu(In, Ga)Se2 thin-film solar cells

    Science.gov (United States)

    Lu, Ming; Xu, Jing; Huang, Jian-Wei

    2016-09-01

    The lowest energies which make Cu, In, Ga, and Se atoms composing Cu(In, Ga)Se2 (CIGS) material displaced from their lattice sites are evaluated, respectively. The non-ionizing energy loss (NIEL) for electron in CIGS material is calculated analytically using the Mott differential cross section. The relation of the introduction rate (k) of the recombination centers to NIEL is modified, then the values of k at different electron energies are calculated. Degradation modeling of CIGS thin-film solar cells irradiated with various-energy electrons is performed according to the characterization of solar cells and the recombination centers. The validity of the modeling approach is verified by comparison with the experimental data. Project supported by the National Natural Science Foundation of China (Grant No. 11547151).

  6. Biomimetic utilization of solar energy

    Science.gov (United States)

    Dzhabiev, T. S.; Shilov, Aleksandr E.

    2012-12-01

    The most interesting recent publications dealing with so-called artificial photosynthesis, i.e., the development of photocatalytic converters of solar energy to the chemical bond energy using the fundamental principles of natural oxygenic photosynthesis, are discussed. The key stages of photosynthesis that should be reproduced in the artificial converters include light harvesting and transport of the light quantum to reaction centres where photoinduced charge separation occurs to give elementary reducing agents and oxidants (electrons and holes). The dark catalytic reactions involving the elementary reducing agents and oxidants give stable end products, namely, dioxygen and carbohydrates in the natural photosynthesis or dioxygen and hydrogen in the artificial photosynthesis. The bibliography includes 99 references.

  7. Organoruthenium Complexes for Solar Energy Harvesting

    NARCIS (Netherlands)

    Wadman, S.H.

    2008-01-01

    One of the greatest challenges of this time is providing the world with the energy it needs to sustain human kind's current standard of living. Solar energy is the most abundant and ubiquitous renewable energy source available, and as such it holds great promises. Traditionally, the field of solar e

  8. The thermodynamic solar energy; Le solaire thermodynamique

    Energy Technology Data Exchange (ETDEWEB)

    Rivoire, B. [Centre National de la Recherche Scientifique (CNRS-IMP), 66 - Perpignan (France)

    2002-04-01

    The thermodynamic solar energy is the technic in the whole aiming to transform the solar radiation energy in high temperature heat and then in mechanical energy by a thermodynamic cycle. These technic are most often at an experimental scale. This paper describes and analyzes the research programs developed in the advanced countries, since 1980. (A.L.B.)

  9. Combined solar collector and energy storage system

    Science.gov (United States)

    Jensen, R. N. (Inventor)

    1980-01-01

    A combined solar energy collector, fluid chiller and energy storage system is disclosed. A movable interior insulated panel in a storage tank is positionable flush against the storage tank wall to insulate the tank for energy storage. The movable interior insulated panel is alternately positionable to form a solar collector or fluid chiller through which the fluid flows by natural circulation.

  10. Chalcogenide Materials for Solar Energy Conversion

    Directory of Open Access Journals (Sweden)

    Péter Turmezei

    2004-11-01

    Full Text Available The problem of electrical energy storage can possibly be solved with the help of electrochemical solar cells, which are suitable to generate either electrical energy or hydrogen gas under special conditions. The greatest problem of the electrochemical solar cell technology is to find novel materials which have appropriate properties for electrochemical energy conversion. In this work Cd4GeSe6, a novel material for electrochemical solar cells, will be presented.

  11. Modeling the time and energy behavior of the GCR intensity in the periods of low activity around the last three solar minima

    CERN Document Server

    Krainev, M B; Kalinin, M S; Svirzhevskaya, A K; Svirzhevsky, N S

    2014-01-01

    Using the simple model for the description of the GCR modulation in the heliosphere and the sets of parameters discussed in the accompanying paper we model some features of the time and energy behavior of the GCR intensity near the Earth observed during periods of low solar activity around three last solar minima. In order to understand the mechanisms underlying these features in the GCR behavior, we use the suggested earlier decomposition of the calculated intensity into the partial intensities corresponding to the main processes (diffusion, adiabatic losses, convection and drifts).

  12. Solar Energy Cell with Rare Earth Film

    Institute of Scientific and Technical Information of China (English)

    Li Baojun; Yang Tao; Zhou Yao; Zhou Meng; Fu Xiliang; Fu Li

    2004-01-01

    The characteristic of the solar energy cell with the rare earth film according to theory of molecular structure was introduced.When sunlight shines, the molecules of the rare earth film can absorb energy of the photon and jump to the excited state from the basic state, and play a role in storing solar energy.When sunlight do not shine, the electron of the excited state returns to the basic state, the rare earth film can automatically give out light and shine to surface of the solar cell, which can make solar cell continuously generate electric current.The rare earth film can absorb direct,scattering sunlight, and increase density of solar energy to reach surface of the solar cell, and play focusing function.The rare earth film can bear 350 ~ 500 ℃, which make the solar cell be able to utilize the focusing function system.Because after luminescence of the rare earth film, it can release again the absorbed solar energy through 1 ~ 8 h, and play a role in storing solar energy; The solar cell with the rare-earth film can generate electricity during night and cloudy days, and remarkably increase efficiency of the solar cell.

  13. Assessing the urban solar energy resource potential of Davao City, Philippines, using LiDAR Digital Surface Model (DSM) and GRASS GIS

    Science.gov (United States)

    Teves, Justine; Sola, Eula Fae; Pintor, Ben Hur; Ang, Ma. Rosario Concepcion

    2016-10-01

    Solar energy is emerging as one of the top options for renewable energy sources in the Philippines, with largescale solar photovoltaic (PV) farms being built all over the country. Solar energy resource in the urban environment has great potential in making a city self-sustaining, but has not been fully explored for the country. In order to represent its potential, reliable resource assessment should be done. This study aims to assess the available solar energy resource in Davao City, a trade and commerce hub in southern Philippines. The functions of GRASS GIS, specifically the r.sun module, in modelling incoming solar radiation is discussed, along with the use of a one-meter LiDAR Digital Surface Model (DSM) and Linke Turbidity coefficients as inputs. The average Julian day of each month was used to compute the Global Horizontal Irradiation (GHI) values under clear-sky or cloudless conditions. To account for the effects of the clouds in the study area, the clear-sky indices (Kc) were computed using data from solar recording stations of the Bureau of Soils and Water Management (BSWM) found within and around the region. These were multiplied to the modelled clear-sky GHI rasters to get the real-sky GHI. The results show that the city's average GHI potential ranges from 2693.79 Wh/m2 and 4453.13 Wh/m2. Average values are particularly higher around the months of March and April, while lower values are seen in the months of November and January. Areas with higher potential are seen in the southern portion of the city, consistent in built-up areas.

  14. Upscaling of business model experiments in off-grid PV solar energy in India

    NARCIS (Netherlands)

    Jolly, Suyash; Raven, Rob; Romijn, Henny

    2012-01-01

    Rapidly developing countries like India face numerous challenges related to social and environmental sustainability, which are associated with their fast economic growth and rising energy demand, climate change, and widening disparities between the rich and the poor. Recently, a number of claims hav

  15. Performance study of a laboratory model shallow solar pond with and without single transparent glass cover for solar thermal energy conversion applications.

    Science.gov (United States)

    Ganesh, S; Arumugam, S

    2016-12-01

    The thermal performance of a shallow solar pond with and without the single transparent glass cover has been investigated experimentally. This experiment has been performed during the summer season of 2014 under the operational condition for five different storage volumes of water upto a maximum of 10liter. The pond performance is investigated in terms of the rate of energy collected and its collection efficiency. A Low Density Polyethylene (LDPE) black sheet liner of 200μm thickness was laid on all the interior sides of the pond for solar energy absorption. A clear transparent PVC plastic sheet of 150μm thickness was laid over the water surface as evaporation suppressing membrane. Calibrated Copper constantan thermocouples were used to measure the temperatures of the system. A highest temperature of 81.5°C has been achieved for the stored volume of 2liter of water, when the pond was used with a single transparent glass cover of 5mm thickness. When the shallow solar pond was used without the transparent glass cover the system attained a maximum temperature of 62°C for the same stored volume of 2liter. A comparison between the two conditions of with and without the transparent glass cover, on the thermal performance of the SSP has been reported. A shallow solar pond system of the present type could be used us a source of warm water, of desired temperature, below 10°C which are required for the domestic and industrial utilities. The global warming is increased day by day; inorder to reduce global warming a typical method of small scale shallow solar pond has been used to absorb the radiation from the sun to convert it to useful heat energy by the source of water. The SSP is an eco friendly way to generate energy without polluting our environment and in an environment safety manner. Based on environmental safety this study has experimentally investigated the thermal performance of the shallow solar pond.

  16. Solar Flares and the High Energy Solar Spectroscopic Imager (HESSI)

    Science.gov (United States)

    Holman, Gordon D.; Fisher, Richard R. (Technical Monitor)

    2001-01-01

    Solar flares are the biggest explosions in the solar system. They are important both for understanding explosive events in the Universe and for their impact on human technology and communications. The satellite-based HESSI is designed to study the explosive release of energy and the acceleration of electrons, protons, and other charged particles to high energies in solar flares. HESSI produces "color" movies of the Sun in high-energy X rays and gamma rays radiated by these energetic particles. HESSI's X-ray and gamma-ray images of flares are obtained using techniques similar to those used in radio interferometry. Ground-based radio observations of the Sun provide an important complement to the HESSI observations of solar flares. I will describe the HESSI Project and the high-energy aspects of solar flares, and how these relate to radio astronomy techniques and observations.

  17. The Solar Energy Timetable. Worldwatch Paper 19.

    Science.gov (United States)

    Hayes, Denis

    This publication proposes a timetable for converting the world economy to solar energy. The contents include: (1) A solar-powered world by 2025; (2) Heating and cooling; (3) Renewable fuels; (4) Electricity; (5) Getting there from here; and (6) Notes. Numerous facts are presented within these sections. International solar research programs are…

  18. Development of technologies for solar energy utilization

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-09-01

    With relation to the development of photovoltaic power systems for practical use, studies were made on thin-substrate polycrystalline solar cells and thin-film solar cells as manufacturing technology for solar cells for practical use. The technological development for super-high efficiency solar cells was also being advanced. Besides, the research and development have been conducted of evaluation technology for photovoltaic power systems and systems to utilize the photovoltaic power generation and peripheral technologies. The demonstrative research on photovoltaic power systems was continued. The international cooperative research on photovoltaic power systems was also made. The development of a manufacturing system for compound semiconductors for solar cells was carried out. As to the development of solar energy system technologies for industrial use, a study of elemental technologies was first made, and next the development of an advanced heat process type solar energy system was commenced. In addition, the research on passive solar systems was made. An investigational study was carried out of technologies for solar cities and solar energy snow melting systems. As international joint projects, studies were made of solar heat timber/cacao drying plants, etc. The paper also commented on projects for international cooperation for the technological development of solar energy utilization systems. 26 figs., 15 tabs.

  19. Solar Energy Systems for Ohioan Residential Homeowners

    Science.gov (United States)

    Luckett, Rickey D.

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

  20. Environmental aspects of solar energy technologies

    Energy Technology Data Exchange (ETDEWEB)

    Strojan, C.L.

    1980-09-01

    Solar energy technologies have environmental effects, and these may be positive or negative compared with current ways of producing energy. In this respect, solar energy technologies are no different from other energy systems. Where solar energy technologies differ is that no unresolvable technological problems (e.g., CO/sub 2/ emissions) or sociopolitical barriers (e.g., waste disposal, catastrophic accidents) have been identified. This report reviews some of the environmental aspects of solar energy technologies and ongoing research designed to identify and resolve potential environmental concerns. It is important to continue research and assessment of environmental aspects of solar energy to ensure that unanticipated problems do not arise. It is also important that the knowledge gained through such environmental research be incorporated into technology development programs and policy initiatives.

  1. Solar energy application, economics, and public perception

    CERN Document Server

    Adaramola, Muyiwa

    2015-01-01

    Due to climate change, the rise in energy demand, and issues of energy security, more countries are being forced to reexamine their energy policies and consider more renewable sources of energy. Solar power is expected to play a significant role in the changing face of energy economies, due in a large part to the recent technological advances in the field and the significant decrease in cost. This book describes these advances and examines the current state of solar power from a variety of angles. The various sections of the book cover the following topics: an overview of hybrid solar energy s

  2. Solar energy resources not accounted in Brazilian National Energy Balance

    Energy Technology Data Exchange (ETDEWEB)

    Pinheiro, Paulo Cesar da Costa [Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG (Brazil). Dept. de Engenharia Mecanica], Emails: pinheiro@netuno.Lcc.ufmg.br, pinheiro@demec.ufmg.br

    2009-07-01

    The main development vector of a society is the energy. The solar energy is the main energy source on the planet earth. Brazil is a tropical country, and the incident solar energy on its soil (15 trillion MWh/year) is 20,000 times its annual oil production. Several uses of solar energy are part of our lives in a so natural way that it despised in the consumption and use energy balance. In Brazil, solar energy is used directly in many activities and not accounted for in Energy Balance (BEN 2007), consisting of a virtual power generation. This work aims to make a preliminary assessment of solar energy used in different segments of the Brazilian economy. (author)

  3. Development of solar energy in Peru

    Science.gov (United States)

    Pierson, H. O.; Nahui, A.

    1981-06-01

    Development of solar energy technology utilization in Peru is discussed. Peru receives a high degree of solar radiation (except for part of its coastal area) and has almost an ideal climate for the development of solar energy. The development of low temperature applications, including the design of passive solar heated buildings for the high Andes, the design and evaluation of various types of solar water heaters and crop dryers for both household and industrial uses (based on flat plate collectors), and the construction of a desalinization prototype plant are reported. Photovoltaic systems are investigated for suitable applications and have an excellent potential, especially in telecommunications.

  4. Research opportunities to advance solar energy utilization.

    Science.gov (United States)

    Lewis, Nathan S

    2016-01-22

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

  5. Solar energy research and development: program balance. Annex, Volume II

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-02-01

    Each of the seven solar energy technologies that have been assessed in the study are treated: photovoltaic devices, solar thermal power systems, wind energy systems, solar heating and cooling systems, agricultural and industrial heat processes, biomass conversion technologies, and ocean thermal energy conversion systems. A brief technical overview of storage for solar electric technologies is presented and some principles concerning how different levels of success on electrical storage can affect the commercial viability of solar electric options are discussed. A description is given of the solar penetration model that was developed and applied as an analytical tool in the study. This computer model has served the primary purpose of evaluating the competiveness of the solar energy systems in the markets in which they are expected to compete relative to that of the alternative energy sources. This is done under a variety of energy supply, demand, and price conditions. The seven sections treating the solar energy technologies contain discussions on each of six subject areas: description of the technology; economic projections; the potential contribution of the technology in different marketplaces; environmental considerations; international potential; and the present and possible future emphases within the RD and D program. The priority item for each of the technology sections has been the documentation of the economic projections.

  6. Energy collection efficiency of holographic planar solar concentrators.

    Science.gov (United States)

    Castro, Jose M; Zhang, Deming; Myer, Brian; Kostuk, Raymond K

    2010-02-10

    We analyze the energy collection properties of holographic planar concentrator systems. The effects of solar variation on daily and annual energy collection are evaluated. Hologram diffraction efficiency, polarization, crosstalk in cascaded elements, and constraints imposed by the radiance theorem, as well as solar illumination characteristics, are considered. A planar holographic solar concentrator configuration is designed and modeled to maximize energy collection efficiency during the course of a year without the need for tracking. Results indicated that nearly 50% of the available energy illuminating hologram areas can be collected by photovoltaic cells without the need of tracking.

  7. Application of diffusion research to solar energy policy issues

    Energy Technology Data Exchange (ETDEWEB)

    Roessner, J. D.; Posner, D.; Shoemaker, F.; Shama, A.

    1979-03-01

    This paper examines two types of information requirements that appear to be basic to DOE solar-energy-policy decisions: (1) how can the future market success of solar energy technologies be estimated, and (2) what factors influence the adoption of solar energy technologies, and what specific programs could promote solar energy adoption most effectively. This paper assesses the ability of a body of research, referred to here as diffusion research, to supply information that could partially satisfy these requirements. This assessment proceeds, first, by defining in greater detail a series of policy issues that face DOE. These are divided into cost reduction and performance improvement issues which include issues confronting the technology development component of the solar energy program, and barriers and incentives issues which are most relevant to problems of solar energy application. Second, these issues are translated into a series of questions that the diffusion approach can help resolve. Third, various elements within diffusion research are assessed in terms of their abilities to answer policy questions. Finally, the strengths and limitations of current knowledge about the diffusion of innovations are summarized, the applicability of both existing knowledge and the diffusion approach to the identified solar-energy-policy issues are discussed, and ways are suggested in which diffusion approaches can be modified and existing knowledge employed to meet short- and long-term goals of DOE. The inquiry covers the field of classical diffusion research, market research and consumer behavior, communication research, and solar-energy market-penetration modeling.

  8. Modeling and Control for Smart Grid Integration\\ud of Solar/Wind Energy Conversion System

    OpenAIRE

    2011-01-01

    Performance optimization, system reliability and operational efficiency are key characteristics of smart grid systems. In this paper a novel model of smart grid-connected PV/WT hybrid system is developed. It comprises photovoltaic array, wind turbine, asynchronous (induction) generator, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P&O) algorithm is used for maximizing the generated power based on maximum power point tracker (...

  9. Nuclear Processes at Solar Energy

    CERN Document Server

    Broggini, C

    2003-01-01

    LUNA, Laboratory for Underground Nuclear Astrophysics at Gran Sasso, is measuring fusion cross sections down to the energy of the nucleosynthesis inside stars. Outstanding results obtained up to now are the cross-section measurements within the Gamow peak of the Sun of $^{3}He(^{3}He,2p)^{4}He$ and the $D(p,\\gamma)^{3}He$. The former plays a big role in the proton-proton chain, largely affecting the calculated solar neutrino luminosity, whereas the latter is the reaction that rules the proto-star life during the pre-main sequence phase. The implications of such measurements will be discussed. Preliminary results obtained last year on the study of $^{14}N(p,\\gamma)^{15}O$, the slowest reaction of the CNO cycle, will also be shown.

  10. Light harvesting for quantum solar energy conversion

    Science.gov (United States)

    Markvart, Tomas

    2000-05-01

    's functions can be used to advantage. The Green's function provides a convenient vehicle for the determination of the probability of energy collection - known as the trapping probability in the photosynthetic unit. Using the reciprocity relation, both quantities are shown to be closely related to the distribution of the energy carriers in the dark. The collection probability can then be discussed in detail, by solving the semiconductor device equations in the case of solar cell, and by linking the Green's function formalism to the random walk model in the case of the photosynthetic unit. The concept of resonant energy transfer is beginning to enter the arena of solid-state optoelectronics. It is an aim of this paper to show that similar phenomena - which exist in the domain of bioenergetics - can throw new light on a range of energy transfer and collection processes that are of considerable importance in many modern optoelectronic devices.

  11. Solar Energy Generation in Three Dimensions

    CERN Document Server

    Bernardi, Marco; Wan, Jin H; Villalon, Rachelle; Grossman, Jeffrey C

    2011-01-01

    Optimizing the conversion of solar energy to electricity is central to the World's future energy economy. Flat photovoltaic panels are commonly deployed in residential and commercial rooftop installations without sun tracking systems and using simple installation guidelines to optimize solar energy collection. Large-scale solar energy generation plants use bulky and expensive sun trackers to avoid cosine losses from photovoltaic panels or to concentrate sunlight with mirrors onto heating fluids.[1,2] However, none of these systems take advantage of the three-dimensional nature of our biosphere, so that solar energy collection largely occurs on flat structures in contrast with what is commonly observed in Nature.[3,4] Here we formulate, solve computationally and study experimentally the problem of collecting solar energy in three-dimensions.[5] We demonstrate that absorbers and reflectors can be combined in the absence of sun tracking to build three-dimensional photovoltaic (3DPV) structures that can generate ...

  12. Solar energy education. Renewable energy activities for general science

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Renewable energy topics are integrated with the study of general science. The literature is provided in the form of a teaching manual and includes such topics as passive solar homes, siting a home for solar energy, and wind power for the home. Other energy topics are explored through library research activities. (BCS)

  13. Solar Energy Education. Renewable energy activities for biology

    Energy Technology Data Exchange (ETDEWEB)

    1982-01-01

    An instructional aid for teachers is presented that will allow biology students the opportunity to learn about renewable energy sources. Some of the school activities include using leaves as collectors of solar energy, solar energy stored in wood, and a fuel value test for green and dry woods. A study of organic wastes as a source of fuel is included. (BCS)

  14. Nanostructured Solar Irradiation Control Materials for Solar Energy Conversion

    Science.gov (United States)

    Kang, Jinho; Marshall, I. A.; Torrico, M. N.; Taylor, C. R.; Ely, Jeffry; Henderson, Angel Z.; Kim, J.-W.; Sauti, G.; Gibbons, L. J.; Park, C.; Lowther, S. E.; Lillehei, P. T.; Bryant, R. G.

    2012-01-01

    Tailoring the solar absorptivity (alpha(sub s)) and thermal emissivity (epsilon(sub T)) of materials constitutes an innovative approach to solar energy control and energy conversion. Numerous ceramic and metallic materials are currently available for solar absorbance/thermal emittance control. However, conventional metal oxides and dielectric/metal/dielectric multi-coatings have limited utility due to residual shear stresses resulting from the different coefficient of thermal expansion of the layered materials. This research presents an alternate approach based on nanoparticle-filled polymers to afford mechanically durable solar-absorptive and thermally-emissive polymer nanocomposites. The alpha(sub s) and epsilon(sub T) were measured with various nano inclusions, such as carbon nanophase particles (CNPs), at different concentrations. Research has shown that adding only 5 wt% CNPs increased the alpha(sub s) and epsilon(sub T) by a factor of about 47 and 2, respectively, compared to the pristine polymer. The effect of solar irradiation control of the nanocomposite on solar energy conversion was studied. The solar irradiation control coatings increased the power generation of solar thermoelectric cells by more than 380% compared to that of a control power cell without solar irradiation control coatings.

  15. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The

  16. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  17. Solar energy for industrial process heat

    Science.gov (United States)

    Barbieri, R. H.; Pivirotto, D. L.

    1979-01-01

    Findings of study of potential use for solar energy utilization by California dairy industry, prove that applicable solar energy system furnish much of heat needed for milk processing with large savings in expenditures for oil and gas and ensurance of adequate readily available sources of process heat.

  18. Projects in a Solar Energy Course.

    Science.gov (United States)

    Lindsay, Richard H.

    1983-01-01

    Describes student projects on applications of solar energy optics to home design. Project criterion (requiring sketches and detailed calculations of time rate of energy flow/production) is that half the heat for the heating season be taken from the solar resource; calculations must be based on meteorological data for a specific location. (JM)

  19. Wind loads on solar energy systems

    NARCIS (Netherlands)

    Kampen, B.J.M. van; Geurts, C.P.W.; Borsboom, W.A.; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads 0on solar energy systems,. which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The re

  20. Photovoltaic Solar Energy : From Fundamentals to Applications

    NARCIS (Netherlands)

    Reinders, Angelina H.M.E.; Verlinden, P.J.; van Sark, W.G.J.H.M.; Freundlich, A.

    2016-01-01

    Solar PV is now the third most important renewable energy source, after hydro and wind power, in terms of global installed capacity. Bringing together the expertise of international PV specialists Photovoltaic Solar Energy: From Fundamentals to Applications provides a comprehensive and up-to-date

  1. Solar energy in Norway; Solstroem i Norge

    Energy Technology Data Exchange (ETDEWEB)

    Thorud, Bjoern; Nordal, Siv Helen; Bugge, Lars; Authen, Mari L.; Bernhard, Peter

    2012-10-15

    Enova SF produced in 2010/11 a report that described the potential of solar energy until 2020. Developments in the market for the production of electricity from solar energy happens so fast that it is prepared a new report describing the market and technology per 2012. (eb)

  2. Photovoltaic Solar Energy - From Fundamentals to Applications

    NARCIS (Netherlands)

    Reinders, A.H.M.E.; Verlinden, P.J.; Sark, W.G.J.H.M.; Freundlich, A.

    2017-01-01

    Solar PV is now the third most important renewable energy source, after hydro and wind power, in terms of global installed capacity. Bringing together the expertise of international PV specialists Photovoltaic Solar Energy: From Fundamentals to Applications provides a comprehensive and up-to-date ac

  3. Establishing oleaginous microalgae research models for consolidated bioprocessing of solar energy.

    Science.gov (United States)

    Wang, Dongmei; Lu, Yandu; Huang, He; Xu, Jian

    2012-01-01

    Algal feedstock is the foundation of the emerging algal biofuel industry. However, few algae found in nature have demonstrated the combination of high biomass accumulation rate, robust oil yield and tolerance to environmental stresses, all complex traits that a large-scale, economically competitive production scheme demands. Therefore, untangling the intricate sub-cellular networks underlying these complex traits, in one or a series of carefully selected algal research models, has become an urgent research mission, which can take advantage of the emerging model oleaginous microalgae that have already demonstrated small, simple and tackleable genomes and the potential for large-scale open-pond cultivation. The revolutions in whole-genome-based technologies, coupled with systems biology, metabolic engineering and synthetic biology approaches, would enable the rational design and engineering of algal feedstock and help to fill the gaps between the technical and economical reality and the enormous potential of algal biofuels.

  4. Modeling recombination processes and predicting energy conversion efficiency of dye sensitized solar cells from first principles

    Science.gov (United States)

    Ma, Wei; Meng, Sheng

    2014-03-01

    We present a set of algorithms based on solo first principles calculations, to accurately calculate key properties of a DSC device including sunlight harvest, electron injection, electron-hole recombination, and open circuit voltages. Two series of D- π-A dyes are adopted as sample dyes. The short circuit current can be predicted by calculating the dyes' photo absorption, and the electron injection and recombination lifetime using real-time time-dependent density functional theory (TDDFT) simulations. Open circuit voltage can be reproduced by calculating energy difference between the quasi-Fermi level of electrons in the semiconductor and the electrolyte redox potential, considering the influence of electron recombination. Based on timescales obtained from real time TDDFT dynamics for excited states, the estimated power conversion efficiency of DSC fits nicely with the experiment, with deviation below 1-2%. Light harvesting efficiency, incident photon-to-electron conversion efficiency and the current-voltage characteristics can also be well reproduced. The predicted efficiency can serve as either an ideal limit for optimizing photovoltaic performance of a given dye, or a virtual device that closely mimicking the performance of a real device under different experimental settings.

  5. Solar energy for electricity and fuels.

    OpenAIRE

    Inganäs, Olle; Sundström, V

    2016-01-01

    Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorga...

  6. Solar-energy potential in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Sozen, Adnan; Ozalp, Mehmet [Gazi Univ., Mechanical Education Dept., Ankara (Turkey); Arcaklioglu, Erol [Kirikkale Univ., Mechanical Engineering Dept., Kirikkale (Turkey); Kanit, E. Galip [Turkish State Meteorological Office, Ankara (Turkey)

    2005-04-01

    In this study, a new formula based on meteorological and geographical data was developed to determine the solar-energy potential in Turkey using artificial neural-networks (ANNs). Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) learning algorithms and a logistic sigmoid transfer function were used in the network. Meteorological data for the last four years (2000-2003) from 18 cities (Bilecik, Kirsehir, Akhisar, Bingol, Batman, Bodrum, Uzunkopru, Sile, Bartin, Yalova, Horasan, Polatli, Malazgirt, Koycegiz, Manavgat, Dortyol, Karatas and Birecik) spread over Turkey were used as data in order to train the neural network. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine duration, and mean temperature) were used in the input layer of the network. Solar radiation is the output layer. One-month test data for each city was used, and these months data were not used for training. The results show that the maximum mean absolute percentage error (MAPE) was found to be 3.448% and the R{sup 2} value 0.9987 for Polatli. The best approach was found for Kirsehir (MAPE=1.2257, R{sup 2}=0.9998). The MAPE and R{sup 2} for the testing data were 3.3477 and 0.998534, respectively. The ANN models show greater accuracy for evaluating solar-resource possibilities in regions where a network of monitoring stations has not been established in Turkey. This study confirms the ability of the ANN to predict solar-radiation values precisely (Author)

  7. Solar-energy potential in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Soezen, Adnan; Arcaklioglu, Erol; Oezalp, Mehmet; Kanit, E. Galip

    2005-04-01

    In this study, a new formula based on meteorological and geographical data was developed to determine the solar-energy potential in Turkey using artificial neural-networks (ANNs). Scaled conjugate gradient (SCG) and Levenberg-Marquardt (LM) learning algorithms and a logistic sigmoid transfer function were used in the network. Meteorological data for the last four years (2000 {yields} 2003) from 18 cities (Bilecik, Kirsehir, Akhisar, Bingoel, Batman, Bodrum, Uzunkoeprue, Sile, Bartin, Yalova, Horasan, Polatli, Malazgirt, Koeycegiz, Manavgat, Doertyol, Karatas and Birecik) spread over Turkey were used as data in order to train the neural network. Meteorological and geographical data (latitude, longitude, altitude, month, mean sunshine duration, and mean temperature) were used in the input layer of the network. Solar radiation is the output layer. One-month test data for each city was used, and these months data were not used for training. The results show that the maximum mean absolute percentage error (MAPE) was found to be 3.448% and the R{sup 2} value 0.9987 for Polatli. The best approach was found for Kirsehir (MAPE=1.2257, R{sup 2}=0.9998). The MAPE and R{sup 2} for the testing data were 3.3477 and 0.998534, respectively. The ANN models show greater accuracy for evaluating solar-resource possibilities in regions where a network of monitoring stations has not been established in Turkey. This study confirms the ability of the ANN to predict solar-radiation values precisely.

  8. Application of Solar Energy to Air Conditioning Systems

    Energy Technology Data Exchange (ETDEWEB)

    M, Nash J; J, Harstad A

    1976-11-01

    The results of a survey of solar energy system applications of air conditioning are summarized. Techniques discussed are both solar powered (absorption cycle and the heat engine/ Rankine cycle) and solar related (heat pump). Brief descriptions of the physical implications of various air conditioning techniques, discussions of status, proposed technological improvements, methods of utilization and simulation models are presented, along with an extensive bibliography of related literature.

  9. Application of solar energy to air conditioning systems

    Science.gov (United States)

    Nash, J. M.; Harstad, A. J.

    1976-01-01

    The results of a survey of solar energy system applications of air conditioning are summarized. Techniques discussed are both solar powered (absorption cycle and the heat engine/Rankine cycle) and solar related (heat pump). Brief descriptions of the physical implications of various air conditioning techniques, discussions of status, proposed technological improvements, methods of utilization and simulation models are presented, along with an extensive bibliography of related literature.

  10. Ultrafast Electron Dynamics in Solar Energy Conversion.

    Science.gov (United States)

    Ponseca, Carlito S; Chábera, Pavel; Uhlig, Jens; Persson, Petter; Sundström, Villy

    2017-08-23

    Electrons are the workhorses of solar energy conversion. Conversion of the energy of light to electricity in photovoltaics, or to energy-rich molecules (solar fuel) through photocatalytic processes, invariably starts with photoinduced generation of energy-rich electrons. The harvesting of these electrons in practical devices rests on a series of electron transfer processes whose dynamics and efficiencies determine the function of materials and devices. To capture the energy of a photogenerated electron-hole pair in a solar cell material, charges of opposite sign have to be separated against electrostatic attractions, prevented from recombining and being transported through the active material to electrodes where they can be extracted. In photocatalytic solar fuel production, these electron processes are coupled to chemical reactions leading to storage of the energy of light in chemical bonds. With the focus on the ultrafast time scale, we here discuss the light-induced electron processes underlying the function of several molecular and hybrid materials currently under development for solar energy applications in dye or quantum dot-sensitized solar cells, polymer-fullerene polymer solar cells, organometal halide perovskite solar cells, and finally some photocatalytic systems.

  11. Investigation of Solar and Solar-Gas Thermal Energy Sources

    Directory of Open Access Journals (Sweden)

    Jan Zupa

    2003-01-01

    Full Text Available The article deals with the investigation of solar thermal sources of electrical and heat energy as well as the investigation of hybrid solar-gas thermal sources of electrical and heat energy (so called photothermal sources. Photothermal sources presented here utilize computer-controlled injection of the conversion fluid into special capillary porous substance that is adjusted to direct temperature treatment by the concentrated thermal radiation absorption.

  12. Developing and upgrading of solar system thermal energy storage simulation models. Technical progress report, March 1, 1978-August 31, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, J K; von Fuchs, G F; Warren, A W; Zob, A P

    1979-07-01

    The objective of the program are: 1) collect, standardize, and link existing TES models from the literature and other STO contractors; 2) correlate TES models with available TES component test data; 3) develop streamlined versions of validated TES component models; and 4) provide DOE and industry with a competent solar TES simulation tool. Progress during the reporting period was concerned primarily with the first and second objectives. A rock bed model was evolved and analytical results were correlated with component test data, and water tank model development was continued in detail. Progress is detailed. (WHK)

  13. Solar energy for electricity and fuels.

    Science.gov (United States)

    Inganäs, Olle; Sundström, Villy

    2016-01-01

    Solar energy conversion into electricity by photovoltaic modules is now a mature technology. We discuss the need for materials and device developments using conventional silicon and other materials, pointing to the need to use scalable materials and to reduce the energy payback time. Storage of solar energy can be achieved using the energy of light to produce a fuel. We discuss how this can be achieved in a direct process mimicking the photosynthetic processes, using synthetic organic, inorganic, or hybrid materials for light collection and catalysis. We also briefly discuss challenges and needs for large-scale implementation of direct solar fuel technologies.

  14. Semi-empirical model of solar plages

    Institute of Scientific and Technical Information of China (English)

    FANG; Cheng

    2001-01-01

    [1] Zirin, H., Astrophysics of the Sun, Chapter 7, Cambridge: Cambridge University Press, 1988.[2] Shine, R. A., Linsky, J. L., Physical properties of solar chromospheric plages II. Chromospheric plage models, Solar Phys., 1974, 39: 49.[3] Kelch, W. L., Linsky, J. L., Physical properties of solar chromospheric plages III. Models based on CaII and MgII observations, Solar Phys., 1978, 58: 37.[4] Lemaire, P., Goutlebroze, J. C., Vial, J. C. et al., Physical properties of the solar chromosphere deduced from optically thick lines, A & A, 1981, 103: 160.[5] Fontenla, J. M., Avrett, E. H., Loeser, R., Energy balance in the solar transition region II. Effects of pressure and energy input on hydrostatic models, ApJ, 1991, 377: 712.[6] Fontenla, J. M., Avrett, E. H., Loeser, R., Energy balance in the solar transition region III. Helium emission in hydrostatic, constant-abundance models with diffusion, ApJ, 1993, 406: 319.[7] Pierce, A. K., Slaughter, C., Solar limb darkening I: λλ(30337297), Solar Phys., 1977, 51: 25.[8] Pierce, A. K., Slaughter, C., Weinberger, D., Solar limb darkening in the interval 740424018*!, II, Solar Phys., 1977, 52: 179.[9] Nechel, H., Labs, D., The solar radiation between 3300 and 12500*!, Solar Phys., 1984, 90: 205.[10] Vernazza, J. E., Avrett, E. H., Loeser, R., Structure of the solar chromosphere I. Basic computations and summary of the results, ApJ, 1973, 184: 605.[11] Mihalas, D., Stellar Atmospheres, San Francisco: W. H. Freeman and Company, 1978.[12] Fang, C., Hnoux, J. -C., Self-consistent model of flare heated solar chromosphere, A & A, 1983, 118: 139.[13] Ding, M. D., Fang, C., A semi-empirical model of sunspot penumbra, A & A, 1989, 225: 204.[14] Vernazza, J. E., Avrett, E. H., Loeser, R., Structure of the solar chromosphere III. Models of the EUV brightness components of the quiet Sun, ApJ Suppl., 1981, 45: 635.[15] Canfield, R. C., Athey, R

  15. Spatio-temporal Assessment Of The Land Use Implications Of Solar PV And Bioenergy Deployment In The UK TM Energy Model

    Science.gov (United States)

    Sobral Mourao, Z.; Konadu, D. D.; Skelton, S.; Lupton, R.

    2015-12-01

    The UK TIMES model (UKTM) succeeds the UK MARKAL as the underlying model of the UK Department of Energy and Climate Change (DECC) for long term energy system planning and policy development. It generates energy system pathways which achieve the 80% greenhouse gas (GHG) emissions reduction target by 2050, stipulated in the UK Climate Change Act (2008), at the least possible cost. Some of these pathways prescribe large-scale deployment of solar PV and indigenously sourced bioenergy, which are land intensive and could result in significant land use transitions; but would this create competition and stress for UK land use? To answer the above question, this study uses an integrated spatio-temporal modelling approach, ForeseerTM, which characterises the interdependencies between the energy and land systems by evaluating the land required under each pathways for solar PV and bioenergy, based on scenarios of a range of PV conversion efficiencies, and energy crop yield projections. The outcome is compared with availability of suitable locations for solar PV and sustainable limits of agricultural land appropriation for bioenergy production to assess potential stresses and competition with other land use services. Preliminary results show UKTM pathways could pose significant impact on the UK land use system. Bioenergy deployment could potentially compete with other land services by taking up a significant part of the available UK agricultural land thus competing directly with food production, most notably livestock production. For pathways with significant solar PV deployment, direct competition would not be focussed on the high quality land used for food crop production but rather for land used for livestock production and other ecosystem services.

  16. Solar Energy: Its Technologies and Applications

    Science.gov (United States)

    Auh, P. C.

    1978-06-01

    Solar heat, as a potential source of clean energy, is available to all of us. Extensive R and D efforts are being made to effectively utilize this renewable energy source. A variety of different technologies for utilizing solar energy have been proven to be technically feasible. Here, some of the most promising technologies and their applications are briefly described. These are: Solar Heating and Cooling of Buildings (SHACOB), Solar Thermal Energy Conversion (STC), Wind Energy Conversion (WECS), Bioconversion to Fuels (BCF), Ocean Thermal Energy Conversion (OTEC), and Photovoltaic Electric Power Systems (PEPS). Special emphasis is placed on the discussion of the SHACOB technologies, since the technologies are being expeditiously developed for the near commercialization.

  17. Solar energy: a viable alternative energy source; Energia solar: uma fonte de energia alternativa viavel

    Energy Technology Data Exchange (ETDEWEB)

    Queiros Mattoso e Sousa, Karla de; Sousa, Renato M.A. de [KR Consultoria Projetos e Edificacoes Ltda., MG (Brazil)

    1997-01-01

    This work describes the advantages of using solar energy for water heating instead of conventional systems. Also, the socio and environmental benefits are specified. Finally, the different stages, by which the carrying out of a solar energy project goes through are described, starting by a technical and economical analysis, followed by calculations, and the installation of the solar system. 2 figs., 8 tabs.

  18. Modeling and characterization of double resonant tunneling diodes for application as energy selective contacts in hot carrier solar cells

    Science.gov (United States)

    Jehl, Zacharie; Suchet, Daniel; Julian, Anatole; Bernard, Cyril; Miyashita, Naoya; Gibelli, Francois; Okada, Yoshitaka; Guillemolles, Jean-Francois

    2017-02-01

    Double resonant tunneling barriers are considered for an application as energy selective contacts in hot carrier solar cells. Experimental symmetric and asymmetric double resonant tunneling barriers are realized by molecular beam epitaxy and characterized by temperature dependent current-voltage measurements. The negative differential resistance signal is enhanced for asymmetric heterostructures, and remains unchanged between low- and room-temperatures. Within Tsu-Esaki description of the tunnel current, this observation can be explained by the voltage dependence of the tunnel transmission amplitude, which presents a resonance under finite bias for asymmetric structures. This effect is notably discussed with respect to series resistance. Different parameters related to the electronic transmission of the structure and the influence of these parameters on the current voltage characteristic are investigated, bringing insights on critical processes to optimize in double resonant tunneling barriers applied to hot carrier solar cells.

  19. Potency of Solar Energy Applications in Indonesia

    Directory of Open Access Journals (Sweden)

    Noer Abyor Handayani

    2012-07-01

    Full Text Available Currently, 80% of conventional energy is used to fulfill general public's needs andindustries. The depletion of oil and gas reserves and rapid growth in conventional energyconsumption have continuously forced us to discover renewable energy sources, like solar, wind,biomass, and hydropower, to support economic development in the future. Solar energy travels at aspeed of 186,000 miles per second. Only a small part of the radiant energy that the sun emits intospace ever reaches the Earth, but that is more than enough to supply all our energy demand.Indonesia is a tropical country and located in the equator line, so it has an abundant potential ofsolar energy. Most of Indonesian area get enough intensity of solar radiation with the average dailyradiation around 4 kWh/m2. Basically, the solar systems use solar collectors and concentrators forcollecting, storing, and using solar radiation to be applied for the benefit of domestics, commercials,and industrials. Common applications for solar thermal energy used in industry are the SWHs, solardryers, space heating, cooling systems and water desalination.

  20. A new MATLAB/Simulink model of triple-junction solar cell and MPPT based on artificial neural networks for photovoltaic energy systems

    Directory of Open Access Journals (Sweden)

    Hegazy Rezk

    2015-09-01

    Full Text Available This paper presents a new Matlab/Simulink model of a PV module and a maximum power point tracking (MPPT system for high efficiency InGaP/InGaAs/Ge triple-junction solar cell. The proposed technique is based on Artificial Neural Network. The equivalent circuit model of the triple-junction solar cell includes the parameters of each sub-cell. It is also include the effect of the temperature variations on the energy gap of each sub-cell as well as the diode reverse saturation currents. The implementation of a PV model is based on the triple-junction solar cell in the form of masked block in Matlab/Simulink software package that has a user-friendly icon and dialog. It is fast and accurate technique to follow the maximum power point. The simulation results of the proposed MPPT technique are compared with Perturb and Observe MPPT technique. The output power and energy of the proposed technique are higher than that of the Perturb and Observe MPPT technique. The proposed technique increases the output energy per day for a one PV module from 3.37 kW h to 3.75 kW h, i.e. a percentage of 11.28%.

  1. High Energy Particles in the Solar Corona

    CERN Document Server

    Widom, A; Larsen, L

    2008-01-01

    Collective Ampere law interactions producing magnetic flux tubes piercing through sunspots into and then out of the solar corona allow for low energy nuclear reactions in a steady state and high energy particle reactions if a magnetic flux tube explodes in a violent event such as a solar flare. Filamentous flux tubes themselves are vortices of Ampere currents circulating around in a tornado fashion in a roughly cylindrical geometry. The magnetic field lines are parallel to and largely confined within the core of the vortex. The vortices may thereby be viewed as long current carrying coils surrounding magnetic flux and subject to inductive Faraday and Ampere laws. These laws set the energy scales of (i) low energy solar nuclear reactions which may regularly occur and (ii) high energy electro-weak interactions which occur when magnetic flux coils explode into violent episodic events such as solar flares or coronal mass ejections.

  2. Solar energy storage researchers information user study

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-03-01

    The results of a series of telephone interviews with groups of users of information on solar energy storage are described. In the current study only high-priority groups were examined. Results from 2 groups of researchers are analyzed: DOE-Funded Researchers and Non-DOE-Funded Researchers. 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. 76 FR 60475 - Issuance of a Loan Guarantee to Tonopah Solar Energy, LLC, for the Crescent Dunes Solar Energy...

    Science.gov (United States)

    2011-09-29

    ... Issuance of a Loan Guarantee to Tonopah Solar Energy, LLC, for the Crescent Dunes Solar Energy Project... 2009 (Recovery Act), to Tonopah Solar Energy, LLC (TSE), for construction and start-up of the Crescent Dunes Solar Energy Project (the Project). The Project is a proposed 110- megawatt solar power...

  4. Joint Solar Power Industry and Department of Energy Solar Resource and Meteorological Assessment Project (SOLRMAP)

    Science.gov (United States)

    Wilcox, Steve; Myers, Daryl

    2009-08-01

    The U.S. Department of Energy's National Renewable Energy Laboratory has embarked on a collaborative effort with the solar industry to establish high quality solar and meteorological measurements. This Solar Resource and Meteorological Assessment Project (SOLRMAP) provides high quality measurements to support deployment of concentrating solar thermal power projects in the United States. The no-funds-exchanged collaboration brings NREL solar resource assessment expertise together with industry needs for measurements. The end result will be high quality data sets to support the financing, design, and monitoring of large scale solar power projects for industry in addition to research-quality data for NREL model development. NREL provides consultation for instrumentation and station deployment, along with instrument calibrations, data acquisition, quality assessment, data distribution, and summary reports. Industry participants provide equipment, infrastructure, and station maintenance.

  5. Renewable Energy Solar Power Surges On

    Institute of Scientific and Technical Information of China (English)

    DAVID HENDRICKSON

    2006-01-01

    @@ With the increased focus and attention solar power is receiving around the world as a potentially significant energy alternative, it makes sense that China's solar enterprises are today doing big business and raking in massive profits. Among the most notable returns have been those of newcomer Suntech Power Holdings.

  6. Neutrino Cross Sections at Solar Energies

    Science.gov (United States)

    Strigari, Louis

    2017-01-01

    I will review neutrino nucleus cross section measurements and uncertainties for energies applicable to solar neutrinos. I will discuss how these cross sections are important for interpreting solar neutrino experimental data, and highlight the most important neutrino-nucleus interactions that will be relevant for forthcoming dark matter direct detection experiments. NSF PHY-1522717.

  7. Tower Power: Producing Fuels from Solar Energy

    Science.gov (United States)

    Antal, M. J., Jr.

    1976-01-01

    This article examines the use of power tower technologies for the production of synthetic fuels. This process overcomes the limitations of other processes by using a solar furnace to drive endothermic fuel producing reactions and the resulting fuels serve as a medium for storing solar energy. (BT)

  8. Dormitory Solar-Energy-System Economics

    Science.gov (United States)

    1982-01-01

    102-page report analyzes long-term economic performance of a prepackaged solar energy assembly system at a dormitory installation and extrapolates to four additional sites about the U.S. Method of evaluation is f-chart procedure for solar-heating and domestic hotwater systems.

  9. Energy transfer in the solar system

    Science.gov (United States)

    Jelbring, H.

    2013-12-01

    Different types of energy transfer are presented from the literature and are approached and commented on. It follows from these articles that energy transfer in addition to solar irradiation is less well understood by contemporary scientist. The transformation of energy between kinetic and potential energy in planetary orbits might be of crucial importance for understanding energy transfer between celestial bodies and the development of commensurabilities. There is evidence pointing to interactions (friction) between space and satellites producing volcanism. The reversible transfer of energy between the orbit of Moon and Earth's rotational energy is crucial to the creation of the 13.6-day and 27.3-day periods in both solar variables and Earth bound climate variables. It is hypothesized that the Earth-Moon system is modulating the sunspot numbers and creating both these periods, and that the great planets are responsible for the 11 yr solar cycle.

  10. General solar energy information user study

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-03-01

    This report describes the results of a series of telephone interviews with groups of users of information on general solar energy. 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 13 groups of respondents are analyzed in this report: Loan Officers, Real Estate Appraisers, Tax Assessors, Insurers, Lawyers, Utility Representatives, Public Interest Group Representatives, Information and Agricultural Representatives, Public Interest Group Representatives, Information and Agricultural Specialists at State Cooperative Extension Service Offices, and State Energy Office Representatives. 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.

  11. Active Solar Energy Use Approaching Sustainability

    Directory of Open Access Journals (Sweden)

    NikouJavadiEshkalak,

    2014-06-01

    Full Text Available Nowadays, sustainability becomes one of the most important issues that should be taken into consideration in various fields especially in architecture. Our responsibility for the future generation insinuates us for using renewable energy sources and integrating this pioneer system into the built environment. Although the world is facing problems of fossil fuel resources but unfortunately Utilization of solar energy received limited attention until recently. However, Integrating of active solar energy devices into the building envelopes is one of the good strategies for heat producing and power generating simultaneously from the same building. This paper discusses some characteristics about integration of PV s and solar thermal collectors. Therefore, the aim of this paper is to find suitable and possible ways of PV s and solar thermal collector's building integration in order to increasing energy efficiency without any impact on architectural features. \\

  12. Nanoflare heating model for collisionless solar corona

    Indian Academy of Sciences (India)

    U L VISAKH KUMAR; BILIN SUSAN VARGHESE; P J KURIAN

    2017-02-01

    The problem of coronal heating remains one of the greatest unresolved problems in space science. Magnetic reconnection plays a significant role in heating the solar corona. When two oppositely directed magnetic fields come closer to form a current sheet, the current density of the plasma increases due to which magnetic reconnection and conversion of magnetic energy into thermal energy takes place. The present paper deals with a model for reconnection occurring in the solar corona under steady state in collisionless regime. The model predicts that reconnection time in the solar corona varies inversely with the cube of magnetic field and varies directly with the Lindquist number. Our analysis shows that reconnections are occurring within a time interval of600 s in the solar corona, producing nanoflares in the energy range $10^{21}–10^{23}$ erg/s which matches with Yohkoh X-ray observations.

  13. Nanoflare heating model for collisionless solar corona

    Science.gov (United States)

    Visakh Kumar, U. L.; Varghese, Bilin Susan; Kurian, P. J.

    2017-02-01

    The problem of coronal heating remains one of the greatest unresolved problems in space science. Magnetic reconnection plays a significant role in heating the solar corona. When two oppositely directed magnetic fields come closer to form a current sheet, the current density of the plasma increases due to which magnetic reconnection and conversion of magnetic energy into thermal energy takes place. The present paper deals with a model for reconnection occurring in the solar corona under steady state in collisionless regime. The model predicts that reconnection time in the solar corona varies inversely with the cube of magnetic field and varies directly with the Lindquist number. Our analysis shows that reconnections are occurring within a time interval of 600 s in the solar corona, producing nanoflares in the energy range 10 21-10 23 erg /s which matches with Yohkoh X-ray observations.

  14. Energy Analysis of a Student-Designed Solar House

    Directory of Open Access Journals (Sweden)

    Samantha Wermager

    2013-12-01

    Full Text Available This paper presents the findings from an undergraduate research project concerning the energy efficiency, consumption, and generation of a 1000 ft2 (92.9 m2 solar house. The results were compared to a home of similar size and layout, built using traditional construction methods. The solar house was modeled after the Chameleon House: Missouri University of Science and Technology’s 2013 entry in the U.S. Department of Energy Solar Decathlon. The efficiency of the design was analyzed using Energy-10 Version 1.8 software. For this comparison, a fictional American couple was created and a breakdown of their energy-use habits was recorded to accurately depict the magnitude of energy consumption. A 71% energy savings was forecasted using the Energy-10 software through the incorporation of various energy-conserving strategies in the home’s design. In addition, if a 9.1 kW photovoltaic array is also installed on a home of this size, it is possible to fully offset the energy consumption of the home. The forecasted energy usage and production detailed in this report shall be used for analyzing the integrity of the design of the Chameleon House as well as future solar houses constructed by the Missouri S&T Solar House Team.

  15. Production, consumption and research on solar energy

    DEFF Research Database (Denmark)

    Sanz-Casado, Elias; Lascurain-Sánchez, Maria Luisa; Serrano-Lopez, Antonio Eleazar

    2014-01-01

    An analysis of scientific publications on solar energy was conducted to determine whether public interest in the subject is mirrored by more intense research in the area. To this end, the research published by Spain and Germany, the two EU countries with the highest installed photovoltaic capacit...... intense. The main conclusion is the divergence in Germany and Spain between solar energy demand/output growth, being exponential, and the growth of research papers on the subject, which is linear...

  16. Development of a Greek solar map based on solar model estimations

    Science.gov (United States)

    Kambezidis, H. D.; Psiloglou, B. E.; Kavadias, K. A.; Paliatsos, A. G.; Bartzokas, A.

    2016-05-01

    The realization of Renewable Energy Sources (RES) for power generation as the only environmentally friendly solution, moved solar systems to the forefront of the energy market in the last decade. The capacity of the solar power doubles almost every two years in many European countries, including Greece. This rise has brought the need for reliable predictions of meteorological data that can easily be utilized for proper RES-site allocation. The absence of solar measurements has, therefore, raised the demand for deploying a suitable model in order to create a solar map. The generation of a solar map for Greece, could provide solid foundations on the prediction of the energy production of a solar power plant that is installed in the area, by providing an estimation of the solar energy acquired at each longitude and latitude of the map. In the present work, the well-known Meteorological Radiation Model (MRM), a broadband solar radiation model, is engaged. This model utilizes common meteorological data, such as air temperature, relative humidity, barometric pressure and sunshine duration, in order to calculate solar radiation through MRM for areas where such data are not available. Hourly values of the above meteorological parameters are acquired from 39 meteorological stations, evenly dispersed around Greece; hourly values of solar radiation are calculated from MRM. Then, by using an integrated spatial interpolation method, a Greek solar energy map is generated, providing annual solar energy values all over Greece.

  17. Community impediments to implementation of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Armstrong, M. D.; Armstrong, J. E.

    1979-11-01

    The complete array of institutional problems expected to energy when solar technology are implemented on a national scale is assembled. The findings of the study are presented in two formats. First, the results are organized by the time frames of delays in solar implementation caused by the inherent difficulties a national energy policy would encounter in changing the way a given institution responds to specific solar technologies. Delay categories of 10 years or more, 6 to 8 years, and 3 to 5 years were selected; all were assigned under the assumption that a strong national policy promoting adoption of solar technologies would be in effect. The second format constitutes a description of the difficulties at the community level, associated with implementing each solar technology. (MHR)

  18. Solar electric energy supply at high altitude

    Energy Technology Data Exchange (ETDEWEB)

    Knaupp, W.; Mundschau, E. [Zentrum fur Sonnenenergie- und Wasserstoff-Forschung (ZSW), Ulm (Germany)

    2004-04-01

    Solar-hydrogen systems were analyzed regarding their usability as energy supply system for high altitude platforms. In a first step for an assessment of solar and photovoltaic resources near-ground spectral transmittances of atmosphere were extended with simplified height correction functions to achieve spectral irradiance descriptions versus atmospheric height up to 25 km. The influence of atmospheric height to different solar cell technologies regarding electrical performance was quantified at some examples for the aspect of spectral distribution with the help of the introduced spectral height factor. The main attention during analysis of the whole solar-hydrogen energy system was directed to characteristics of current or near term available technology. Specific power weight of photovoltaic system, electrolyzer, fuel cell and gas tanks and their dependence on operation mode and power range were assessed. A pre-design of a solar-hydrogen energy system was carried out for an airship (volume 580,000 m3) withstanding continuous wind speeds up to {approx} 130 km/h. The calculated coverage ratio of photovoltaic and load share of energy system mark the frame of usability. Depending on the airship size, shape and other external boundary conditions the total electrical energy demand could be covered by a solar-hydrogen energy system of current or near term technology for full year operation. However further investigations are necessary regarding e.g. further mass reductions. (author)

  19. Solar Energy and the Western Asian Countries

    Science.gov (United States)

    De Morais Mendonca Teles, Antonio

    2016-07-01

    The Western Asian countries receive the most abundant solar radiation of the world. They also have enormous reserves of oil and natural gas. But the world reserves of those fuels will certainly diminish greatly as the worldwide demand for energy will increase steadily in the coming decades. And the suppliers of energy will have to contend with public concerns about the polluting effects of those fuels and the possible dangers of nuclear energy. Clearly a power source based on an non exhaustible and non-polluting fuel could be expected to find a role. It now appears that such a source is at hand in the solar energy. Here in this paper, under the principles in the United Nations' Agenda 21, we suggest to Western Asian countries, the study and own development of the following technologies based on solar energy; and comment about them: *photo-voltaic solar cell power plants - in the future, its cost per kilowatt-hour will probably be competitive as to other sources of electrical energy. A new technique, the solar non-imaging concentrator, with amorphous silicon-based thin films solar cells at the focus of the concentrators, can collect and intensify solar radiation far better than conventional concentrators do, thus reducing much more the cost; *bio-gas - using biological gas to produce energy and for heating/cooling purposes; *wind generation of electricity - it's nowadays, a non-expensive technique; *water pump for irrigation and human consuming, driving their power from photovoltaic cells; *and the study and own development of solar lasers for peaceful scientific studies. In this new kind of laser, the external necessary pumping energy comes from the high intensity of sunlight, produced with non-imaging concentrators. Solar lasers can give unexpected new great uses for mankind. Those achievements will require international cooperation and transfer of information, sustained research and development work, and some initial subsides by independent governments. Solar

  20. Silicon nanowires for photovoltaic solar energy conversion.

    Science.gov (United States)

    Peng, Kui-Qing; Lee, Shuit-Tong

    2011-01-11

    Semiconductor nanowires are attracting intense interest as a promising material for solar energy conversion for the new-generation photovoltaic (PV) technology. In particular, silicon nanowires (SiNWs) are under active investigation for PV applications because they offer novel approaches for solar-to-electric energy conversion leading to high-efficiency devices via simple manufacturing. This article reviews the recent developments in the utilization of SiNWs for PV applications, the relationship between SiNW-based PV device structure and performance, and the challenges to obtaining high-performance cost-effective solar cells.

  1. Solar energy control system. [temperature measurement

    Science.gov (United States)

    Currie, J. R. (Inventor)

    1981-01-01

    A solar energy control system for a hot air type solar energy heating system wherein thermocouples are arranged to sense the temperature of a solar collector, a space to be heated, and a top and bottom of a heat storage unit is disclosed. Pertinent thermocouples are differentially connected together, and these are employed to effect the operation of dampers, a fan, and an auxiliary heat source. In accomplishing this, the differential outputs from the thermocouples are amplified by a single amplifier by multiplexing techniques. Additionally, the amplifier is corrected as to offset by including as one multiplex channel a common reference signal.

  2. 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.

  3. Bioinspired fractal electrodes for solar energy storages.

    Science.gov (United States)

    Thekkekara, Litty V; Gu, Min

    2017-03-31

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10(-3) Whcm(-3). In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10(-1) Whcm(-3)- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications.

  4. Bioinspired fractal electrodes for solar energy storages

    Science.gov (United States)

    Thekkekara, Litty V.; Gu, Min

    2017-03-01

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10-3 Whcm-3. In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10-1 Whcm-3- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications.

  5. Bioinspired fractal electrodes for solar energy storages

    Science.gov (United States)

    Thekkekara, Litty V.; Gu, Min

    2017-01-01

    Solar energy storage is an emerging technology which can promote the solar energy as the primary source of electricity. Recent development of laser scribed graphene electrodes exhibiting a high electrical conductivity have enabled a green technology platform for supercapacitor-based energy storage, resulting in cost-effective, environment-friendly features, and consequent readiness for on-chip integration. Due to the limitation of the ion-accessible active porous surface area, the energy densities of these supercapacitors are restricted below ~3 × 10−3 Whcm−3. In this paper, we demonstrate a new design of biomimetic laser scribed graphene electrodes for solar energy storage, which embraces the structure of Fern leaves characterized by the geometric family of space filling curves of fractals. This new conceptual design removes the limit of the conventional planar supercapacitors by significantly increasing the ratio of active surface area to volume of the new electrodes and reducing the electrolyte ionic path. The attained energy density is thus significantly increased to ~10−1 Whcm−3- more than 30 times higher than that achievable by the planar electrodes with ~95% coulombic efficiency of the solar energy storage. The energy storages with these novel electrodes open the prospects of efficient self-powered and solar-powered wearable, flexible and portable applications. PMID:28361924

  6. Adjudication accessibility of the solar energy with GIS tools

    Directory of Open Access Journals (Sweden)

    Radim Rybár

    2007-06-01

    Full Text Available Constantly increase prise of oil and natural gas at the world market, increase consumption of electric power forces people to look for new energy sources. Concentration to renewable energy is an attention of specialist and non-professional public. The solar energy is one of the renewable energy. A lot of different factors influence as possibilities using the solar energy. For adjudication possibilities using solar energy is needed to know and calculate quantity accessibility of radiation and its energy for potential locality. This calculation is determined by geographic location, critical time, climatic and meteorological conditions, and position study plain. GIS tools can be very useful for this calculation. Created digital terrain model of Košice fold is used for the adjudication accessibility solar energy. The basic attribute of digital terrain model is used, such as possibilities deduce more parameters like slope and aspect. Basic location parameter of adjudication plain by determine accessibility of the solar radiation is a slope β and an azimuth plain normale An.

  7. Solar energy utilization in the USSR

    Science.gov (United States)

    Shpilrain, E. E.

    1991-05-01

    The conditions for solar energy utilization in the USSR are not too favorable. Only in the country's southern regions is there sufficient insolation to make solar energy utilization economic. In higher latitudes, only seasonal use of solar energy is reasonable. Up to now, the main application of solar energy has been to produce low-temperature heat for hot water production, drying of agricultural goods, space heating and thermal treatment of concrete. A substantial proportion of the solar heating installations are flat plate solar collectors. The total installed area of solar collectors slightly exceeds 100,000 square meters. The collectors are produced by large- and small-scale industry. Where selective coatings are applied to the absorber plates, black nickel or chromium are the main coating materials. Recently launched new projects aim to develop and produce advanced collectors, with enhanced efficiency and reliability. There has been substantial progress in developing photovoltaic (PV) cells for space applications, but terrestrial application of PV is still in a very early stage. Annual production of PV cells totals about 100 kW, based on mono- or polycrystalline silicon. R&D work on thin-film PV cells is in progress. Work is in progress on the development of automated production lines to manufacture 1 MW/yr of crystalline and amorphous silicon. A 5-MW tower-type demonstration plant, with a circular heliostat field, uses steam as the working fluid. Experience with this plant has revealed several disadvantages, including commonwealth of independent states.

  8. Environmental benefits of domestic solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Kalogirou, Soteris A. [Higher Technical Inst., Dept. of Mechanical Engineering, Nicosia (Cyprus)

    2004-11-01

    All nations of the world depend on fossil fuels for their energy needs. However the obligation to reduce CO{sub 2} and other gaseous emissions in order to be in conformity with the Kyoto agreement is the reason behind which countries turn to non-polluting renewable energy sources. In this paper the pollution caused by the burning of fossil fuels is initially presented followed by a study on the environmental protection offered by the two most widely used renewable energy systems, i.e. solar water heating and solar space heating. The results presented in this paper show that by using solar energy, considerable amounts of greenhouse polluting gases are avoided. For the case of a domestic water heating system, the saving, compared to a conventional system, is about 80% with electricity or Diesel backup and is about 75% with both electricity and Diesel backup. In the case of space heating and hot water systems the saving is about 40%. It should be noted, however, that in the latter, much greater quantities of pollutant gases are avoided. Additionally, all systems investigated give positive and very promising financial characteristics. With respect to life cycle assessment of the systems, the energy spent for manufacture and installation of the solar systems is recouped in about 1.2 years, whereas the payback time with respect to emissions produced from the embodied energy required for the manufacture and installation of the systems varies from a few months to 9.5 years according to the fuel and the particular pollutant considered. Moreover, due to the higher solar contribution, solar water heating systems have much shorter payback times than solar space heating systems. It can, therefore, be concluded that solar energy systems offer significant protection to the environment and should be employed whenever possible in order to achieve a sustainable future. (Author)

  9. Magnetic Energy Release in Solar Flares

    Science.gov (United States)

    Forbes, Terry G.

    2017-01-01

    Solar flares are the result of a rapid release of magnetic energy stored in the solar corona. An ideal-MHD process, such as a loss of magnetic equilibrium, most likely initiates the flare, but the non-ideal process of magnetic reconnection quickly becomes the dominant mechanism by which energy is released. Within the last few years EUV and X-ray instruments have directly observed the kind of plasma flows and heating indicative of magnetic reconnection. Relatively cool plasma is observed moving slowly into the reconnection region where it is transformed into two high-temperature, high-speed outflow jets moving in opposite directions. Observations of the flow in these jets suggest that they are accelerated to the ambient Alfvén speed in a manner that resembles the reconnection process first proposed by H. E. Petschek in 1964. This result is somewhat surprising because Petschek-type reconnection does not occur in most numerical simulations of magnetic reconnection. The apparent contradiction between the observations and the simulations can be understood by the fact that most simulations assume a uniform resistivity model that is unlikely to occur in reality. Recently, we have developed a theory that shows how the type of reconnection is related to the plasma resistivity. The theory is based on a form of the time-dependent, MHD-nozzle equations that incorporate the plasma resistivity. These equations are very similar to the equations used to describe magnetized plasma flow in astrophysical jets.

  10. The state of solar energy resource assessment in Chile

    Energy Technology Data Exchange (ETDEWEB)

    Ortega, Alberto; Escobar, Rodrigo [Mechanical and Metallurgical Engineering Department, Pontificia Universidad Catolica de Chile, Vicuna Mackenna 4860, Macul, Santiago (Chile); Colle, Sergio [Laboratorios de Engenharia de Processos de Conversao e Tecnologia de Energia - LEPTEN, Mechanical Engineering Department, Universidade Federal de Santa Catarina, Florianopolis (Brazil); de Abreu, Samuel Luna [IFSC - Instituto Federal de Santa Catarina, Campus Sao Jose, Sao Jose - SC (Brazil)

    2010-11-15

    The Chilean government has determined that a renewable energy quota of up to 10% of the electrical energy generated must be met by 2024. This plan has already sparked interest in wind, geothermal, hydro and biomass power plants in order to introduce renewable energy systems to the country. Solar energy is being considered only for demonstration, small-scale CSP plants and for domestic water heating applications. This apparent lack of interest in solar energy is partly due to the absence of a valid solar energy database, adequate for energy system simulation and planning activities. One of the available solar radiation databases is 20-40 years old, with measurements taken by pyranographs and Campbell-Stokes devices. A second database from the Chilean Meteorological Service is composed by pyranometer readings, sparsely distributed along the country and available from 1988, with a number of these stations operating intermittently. The Chilean government through its National Energy Commission (CNE) has contracted the formulation of a simulation model and also the deployment of network of measurement stations in northern Chile. Recent efforts by the authors have resulted in a preliminary assessment by satellite image processing. Here, we compare the existing databases of solar radiation in Chile. Monthly mean solar energy maps are created from ground measurements and satellite estimations and compared. It is found that significant deviation exists between sources, and that all ground-station measurements display unknown uncertainty levels, thus highlighting the need for a proper, country-wide long-term resource assessment initiative. However, the solar energy levels throughout the country can be considered as high, and it is thought that they are adequate for energy planning activities - although not yet for proper power plant design and dimensioning. (author)

  11. Study of energy transfer from the solar wind to Earth's magnetosphere using the 3D- MHD BATS-R-US global model

    Science.gov (United States)

    Jauer, P. R.; Gonzalez, W. D.; de Souza Costa, C. L.; Souza, V. M.

    2013-12-01

    The interaction, transport and conversion of energy between the solar wind and Earth's magnetosphere have been studied for decades through in situ measurements and Magnetohydrodynamics simulation, (MHD). Nevertheless, due to the vast regions of space and nonlinearities of the physical processes there are many questions that still remain without conclusive answers. Currently, the MHD simulation is a powerful tool that helps other means of already existing research, even within its theoretical limitation; it provides information of the space regions where in situ measurements are rare or nonexistent. The aim of this work is the study of energy transfer from the solar wind through the calculation of the divergence of the Poynting vector for the inner regions of the Earth's magnetosphere, especially the magneto tail using 3D global MHD numerical code Space Weather Modelling Framework (SWMF) / (Block Adaptive Tree Solar wind Roe Upwind Scheme) (BATS-R-US), developed by the University of Michigan. We conducted a simulation study for the event that occurred on September 21-27, 1999, for which the peak value of the interplanetary magnetic field was -22 nT, and gave rise to an intense magnetic storm with peak Dst of -160 nT. Furthermore, we compare the results of the power estimated by the model - through the integration of the Poynting vector in rectangular region of the tail, with a domain -130 powerful tool to reproduce the observations with a good degree of reliability.

  12. The solar energy; L'Energie solaire

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2004-07-01

    This document provides information the today technology concerning the photovoltaic cells and presents the research programs in the domain: silver cells, black silicon, spherical cells, mini sensors, solar spectrum cells Hercules europe project of solar energy concentration. Many Internet addresses are provided. (A.L.B.)

  13. The HESP (High Energy Solar Physics) project

    Science.gov (United States)

    Kai, K.

    1986-01-01

    A project for space observations of solar flares for the coming solar maximum phase is briefly described. The main objective is to make a comprehensive study of high energy phenomena of flares through simultaneous imagings in both hard and soft X-rays. The project will be performed with collaboration from US scientists. The HESP (High Energy Solar Physics) WG of ISAS (Institute of Space and Astronautical Sciences) has extensively discussed future aspects of space observations of high energy phenomena of solar flares based on successful results of the Hinotori mission, and proposed a comprehensive research program for the next solar maximum, called the HESP (SOLAR-A) project. The objective of the HESP project is to make a comprehensive study of both high energy phenomena of flares and quiet structures including pre-flare states, which have been left uncovered by SMM and Hinotori. For such a study simultaneous imagings with better resolutions in space and time in a wide range of energy will be extremely important.

  14. Groove / Solar energy cataloque; Groove aurinkoenergian yritysluettelo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2013-06-01

    According to Tekes, renewable energy offer Finnish companies opportunities for renewal and international growth. Especially in the field of solar energy, development is fast and the market is growing rapidly. The purpose of this catalogue is to provide information about organizations active in the field of solar energy so that different players can find each other more easily. Information is provided about organizations active both on the supply side (solar energy solution and service providers) and demand side (cities, construction contractors, real estate owners) as well as research teams at universities and research centers. We hope that this catalogue will help different actors to find each other both nationally and internationally so that good development and demonstration projects in the field of solar energy can get started. Tekes participates for instance in Solar Eranet, a joint effort of several funding organizations in Europe support transnational solar projects. This catalogue is provided by Tekes program Groove - Growth from renewables. Tekes' programmes and initiatives are topical entities targeted at financial and expert service areas. Within the programmes and initiatives, businesses and public research units can develop new know-how, build networks and have an impact on the development of their field. (orig.)

  15. VT Renewable Energy Sites - Solar

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Renewable Energy Atlas of Vermont and this dataset were created to assist town energy committees, the Clean Energy Development Fund and other...

  16. Harnessing Solar Energy for Every Home: Energy Saving Applications

    OpenAIRE

    2014-01-01

    Most of the present day resources of energy are limited and irreplaceable. The next generation will face acute energy crisis if alternate resources of energy are not developed concurrently. Increasing cost and import of conventional resources have bad effect on the economy of a country, and the only cheaper solution is “unlimited power” from the sun. The use of solar energy is so far limited in household applications. In fact, if we harness only 0.0034 percent of the solar energy reaching the...

  17. 24 CFR 203.18a - Solar energy system.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 2 2010-04-01 2010-04-01 false Solar energy system. 203.18a... § 203.18a Solar energy system. (a) The dollar limitation provided in § 203.18(a) may be increased by up... to the installation of a solar energy system. (b) Solar energy system is defined as any...

  18. Passive solar energy information user study

    Energy Technology Data Exchange (ETDEWEB)

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

    1980-11-01

    The results of a series of telephone interviews with groups of users of information on passive solar heating and cooling 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 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 seven passive groups respondents are analyzed in this report: Federally Funded Researchers, Manufacturer Representatives, Architects, Builders, Educators, Cooperative Extension Service County Agents, and Homeowners. 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.

  19. Economic and Environmental Consequences of Widespread Expansion of Solar energy

    Science.gov (United States)

    Satija, Gaurav

    The purpose of the thesis is to examine the sustainability of an expansion in solar energy subject to resource constraints of Indium. Coal and natural gas are taken as competitors for solar in the energy market. The consumer electronics market also competes with solar PV production because of Indium's use in the manufacturing of LCD screens. A partial equilibrium model is made which determines the rate of extraction of indium, coal and natural gas endogenously. Consumer demand is modeled by the use of cost shares. Generation of electricity and production of LCDs are modeled using Constant Elasticity of Substitution functions. Initial production capacity for both electricity and LCD is considered in the model. The model then endogenously determines the level of investment required. Model simulations are performed to predict the extraction paths and production levels for a timeline of 100 years. A sensitivity analysis is performed to see the reaction of the model to changes in consumer demand and learning rates in solar energy. The response of the model to imposition of various emission caps is also shown. Results of the model show that indium scarcity prevents solar from expanding significantly to a level where it can take over from non-renewable sources of energy. Increased research in solar technologies would not be of much help unless more Indium is available, either by recycling of solar PVs and LCDs or searching for alternate technologies to manufacture LCD screes. Emission caps are able to control excessive usage of fossil fuels and preserve them for a longer time.

  20. Solar combisystems with forecast control to increase the solar fraction and lower the auxiliary energy cost

    DEFF Research Database (Denmark)

    Perers, Bengt; Furbo, Simon; Fan, Jianhua

    2011-01-01

    Solar Combi systems still need quite a lot of auxiliary energy especially in small systems without seasonal storage possibilities. The control of the auxiliary energy input both in time and power is important to utilize as much as possible of the solar energy available from the collectors and also...... energy sources. It can be either direct electric heating elements or a heat pump upgrading ambient energy in the air, ground, solar collector or waste heat from the house. The paper describes system modeling and simulation results. Advanced laboratory experiments are also starting now with three...... to use low backup energy prices during the day if electricity is used. The storage function and both stratified charging and extraction of heat, are very important, to separate different temperature zones in the storage. This paper describes a step towards forecast control for electricity based auxiliary...

  1. Solar Neutrino Data, Solar Model Uncertainties and Neutrino Oscillations

    CERN Document Server

    Krauss, L M; White, M; Krauss, Lawrence M.; Gates, Evalyn; White, Martin

    1993-01-01

    We incorporate all existing solar neutrino flux measurements and take solar model flux uncertainties into account in deriving global fits to parameter space for the MSW and vacuum solutions of the solar neutrino problem.

  2. Solar Neutrino Data, Solar Model Uncertainties and Neutrino Oscillations

    OpenAIRE

    1992-01-01

    We incorporate all existing solar neutrino flux measurements and take solar model flux uncertainties into account in deriving global fits to parameter space for the MSW and vacuum solutions of the solar neutrino problem.

  3. Energy Savings for Solar Heating Systems

    DEFF Research Database (Denmark)

    Thür, Alexander; Furbo, Simon; Shah, Louise Jivan

    2006-01-01

    showed a good degree of similarity. With the boiler model, various simulations of solar domestic hot water heating systems were done for different hot water demands and collector sizes. The result shows that the potential of fuel reduction can be much higher than the solar gain of the solar thermal...... system. For some conditions the fuel reduction can be up to the double of the solar gain due to a strong increase of the system efficiency. As the monitored boilers were not older than 3 years, it can be assumed that the saving potential with older boilers could be even higher than calculated...

  4. Multiscale modeling and experimental interpretation of perovskite oxide materials in thermochemical energy storage and conversion for application in concentrating solar power

    Science.gov (United States)

    Albrecht, Kevin J.

    Decarbonization of the electric grid is fundamentally limited by the intermittency of renewable resources such as wind and solar. Therefore, energy storage will play a significant role in the future of grid-scale energy generation to overcome the intermittency issues. For this reason, concentrating solar power (CSP) plants have been a renewable energy generation technology of interest due to their ability to participate in cost effective and efficient thermal energy storage. However, the ability to dynamically dispatch a CSP plant to meet energy demands is currently limited by the large quantities of sensible thermal energy storage material needed in a molten salt plant. Perovskite oxides have been suggested as a thermochemical energy storage material to enhance the energy storage capabilities of particle-based CSP plants, which combine sensible and chemical modes of energy storage. In this dissertation, computational models are used to establish the thermochemical energy storage potential of select perovskite compositions, identify system configurations that promote high values of energy storage and solar-to-electric efficiency, assess the kinetic and transport limitation of the chemical mode of energy storage, and create receiver and reoxidation reactor models capable of aiding in component design. A methodology for determining perovskite thermochemical energy storage potential is developed based on point defect models to represent perovskite non-stoichiometry as a function of temperature and gas phase oxygen partial pressure. The thermodynamic parameters necessary for the model are extracted from non-stoichiometry measurements by fitting the model using an optimization routine. The procedure is demonstrated for Ca0.9Sr0.1MnO 3-d which displayed combined energy storage values of 705.7 kJ/kg -1 by cycling between 773 K and 0.21 bar oxygen to 1173 K and 10 -4 bar oxygen. Thermodynamic system-level models capable of exploiting perovskite redox chemistry for energy

  5. Toward Revealing the Critical Role of Perovskite Coverage in Highly Efficient Electron-Transport Layer-Free Perovskite Solar Cells: An Energy Band and Equivalent Circuit Model Perspective.

    Science.gov (United States)

    Huang, Like; Xu, Jie; Sun, Xiaoxiang; Du, Yangyang; Cai, Hongkun; Ni, Jian; Li, Juan; Hu, Ziyang; Zhang, Jianjun

    2016-04-20

    Currently, most efficient perovskite solar cells (PVKSCs) with a p-i-n structure require simultaneously electron transport layers (ETLs) and hole transport layers (HTLs) to help collecting photogenerated electrons and holes for obtaining high performance. ETL free planar PVKSC is a relatively new and simple structured solar cell that gets rid of the complex and high temperature required ETL (such as compact and mesoporous TiO2). Here, we demonstrate the critical role of high coverage of perovskite in efficient ETL free PVKSCs from an energy band and equivalent circuit model perspective. From an electrical point of view, we confirmed that the low coverage of perovskite does cause localized short circuit of the device. With coverage optimization, a planar p-i-n(++) device with a power conversion efficiency of over 11% was achieved, implying that the ETL layer may not be necessary for an efficient device as long as the perovskite coverage is approaching 100%.

  6. Closed landfills to solar energy power plants: Estimating the solar potential of closed landfills in California

    Science.gov (United States)

    Munsell, Devon R.

    Solar radiation is a promising source of renewable energy because it is abundant and the technologies to harvest it are quickly improving. An ongoing challenge is to find suitable and effective areas to implement solar energy technologies without causing ecological harm. In this regard, one type of land use that has been largely overlooked for siting solar technologies is closed or soon to be closed landfills. Utilizing Geographic Information System (GIS) based solar modeling; this study makes an inventory of solar generation potential for such sites in the state of California. The study takes account of various site characteristics in relation to the siting needs of photovoltaic (PV) geomembrane and dish-Stirling technologies (e.g., size, topography, closing date, solar insolation, presence of landfill gas recovery projects, and proximity to transmission grids and roads). This study reaches the three principal conclusions. First, with an estimated annual solar electricity generation potential of 3.7 million megawatt hours (MWh), closed or soon to be closed landfill sites could provide an amount of power significantly larger than California's current solar electric generation. Secondly, the possibility of combining PV geomembrane, dish-Stirling, and landfill gas (LFG) to energy technologies at particular sites deserves further investigation. Lastly, there are many assumptions, challenges, and limitations in conducting inventory studies of solar potential for specific sites, including the difficulty in finding accurate data regarding the location and attributes of potential landfills to be analyzed in the study. Furthermore, solar modeling necessarily simplifies a complex phenomenon, namely incoming solar radiation. Additionally, site visits, while necessary for finding details of the site, are largely impractical for a large scale study.

  7. Rosier future for solar energy conversion

    Institute of Scientific and Technical Information of China (English)

    SONG Jianlan

    2008-01-01

    @@ Recent progress in dye-sensitized solar cells (DSCs) research and development,which use innovative light-harvesting dye (the "sensitizer") to improve the optical absorption coefficient of the stained nanostructured electrodes,might color our seemingly dimming future energy security with a tint of rose,despite the looming depletion of fossil fuels.Costing only 10~20% as its silicon counterparts,the new devices might make it affordable for much more people to utilize solar energy,a handy renewable energy source.

  8. Using Solar Energy to Desalinate Water.

    Science.gov (United States)

    Tabor, Harry Z.

    1978-01-01

    Material presented is adapted from Desalination with Solar Energy, a paper presented before the International Symposium on Energy Sources and Development, held in Spain in 1977. Desalination systems energized by the sun, conditions governing their efficiency, and their costs are discussed. (HM)

  9. Energy Primer: Solar, Water, Wind, and Biofuels.

    Science.gov (United States)

    Portola Inst., Inc., Menlo Park, CA.

    This is a comprehensive, fairly technical book about renewable forms of energy--solar, water, wind, and biofuels. The biofuels section covers biomass energy, agriculture, aquaculture, alcohol, methane, and wood. The focus is on small-scale systems which can be applied to the needs of the individual, small group, or community. More than one-fourth…

  10. Energy Primer: Solar, Water, Wind, and Biofuels.

    Science.gov (United States)

    Portola Inst., Inc., Menlo Park, CA.

    This is a comprehensive, fairly technical book about renewable forms of energy--solar, water, wind, and biofuels. The biofuels section covers biomass energy, agriculture, aquaculture, alcohol, methane, and wood. The focus is on small-scale systems which can be applied to the needs of the individual, small group, or community. More than one-fourth…

  11. Modeling, Control, and Simulation of a Solar Hydrogen/Fuel Cell Hybrid Energy System for Grid-Connected Applications

    Directory of Open Access Journals (Sweden)

    Tourkia Lajnef

    2013-01-01

    Full Text Available Different energy sources and converters need to be integrated with each other for extended usage of alternative energy, in order to meet sustained load demands during various weather conditions. The objective of this paper is to associate photovoltaic generators, fuel cells, and electrolysers. Here, to sustain the power demand and solve the energy storage problem, electrical energy can be stored in the form of hydrogen. By using an electrolyser, hydrogen can be generated and stored for future use. The hydrogen produced by the electrolyser using PV power is used in the FC system and acts as an energy buffer. Thus, the effects of reduction and even the absence of the available power from the PV system can be easily tackled. Modeling and simulations are performed using MATLAB/Simulink and SimPowerSystems packages and results are presented to verify the effectiveness of the proposed system.

  12. Port of Galveston Solar Energy Project

    Energy Technology Data Exchange (ETDEWEB)

    Falcioni, Diane [Port of Galveston (POG), Galveston, TX (United States); Cuclis, Alex [Houston Advanced Research Center, The Woodlands, TX (United States); Freundlich, Alex [Univ. of Houston, Houston, TX (United States)

    2014-03-31

    This study on the performance characteristics of existing solar technologies in a maritime environment was funded by an award given to The Port of Galveston (POG) from the U.S. Department of Energy (DOE). The study includes research performed by The Center for Advanced Materials at the University of Houston (UH). The UH researchers examined how solar cell efficiencies and life spans can be improved by examining the performance of a variety of antireflective (AR) coatings mounted on the top of one of the POG’s Cruise Terminals. Supplemental supporting research was performed at the UH laboratories. An educational Kiosk was constructed with a 55” display screen providing information about solar energy, the research work UH performed at POG and real time data from the solar panels located on the roof of the Cruise Terminal. The Houston Advanced Research Center (HARC) managed the project.

  13. On the energy release in solar flares

    CERN Document Server

    Pustil'nik, L A; Beskrovnaya, N G; 10.1063/1.3701351

    2012-01-01

    High-resolution observations show the fine structure of the global equilibrium magnetic field configuration in solar atmosphere to be essentially different from that assumed in the traditional 'potential + force-free' field scenarios. The interacting large-scale structures of fine field elements are separated by numerous non-force-free elements (tangential discontinuities) which are neglected in the traditional field picture. An incorporation of these elements into the model implies a dynamical rather than statical character of equilibrium of the field configuration. A transition of the system into flaring can be triggered by the ballooning mode of flute instability of prominences or/and coronal condensations. Tearing-mode and MHD instabilities as well as the effects of overheating of the turbulent current sheet prevent the field from stationary reconnection as it is adopted in the traditional scenario. We speculate around the assumption that the energy release in active regions is governed by the same scenar...

  14. Inorganic perovskite photocatalysts for solar energy utilization.

    Science.gov (United States)

    Zhang, Guan; Liu, Gang; Wang, Lianzhou; Irvine, John T S

    2016-10-24

    The development and utilization of solar energy in environmental remediation and water splitting is being intensively studied worldwide. During the past few decades, tremendous efforts have been devoted to developing non-toxic, low-cost, efficient and stable photocatalysts for water splitting and environmental remediation. To date, several hundreds of photocatalysts mainly based on metal oxides, sulfides and (oxy)nitrides with different structures and compositions have been reported. Among them, perovskite oxides and their derivatives (layered perovskite oxides) comprise a large family of semiconductor photocatalysts because of their structural simplicity and flexibility. This review specifically focuses on the general background of perovskite and its related materials, summarizes the recent development of perovskite photocatalysts and their applications in water splitting and environmental remediation, discusses the theoretical modelling and calculation of perovskite photocatalysts and presents the key challenges and perspectives on the research of perovskite photocatalysts.

  15. Evaluation of solar radiation abundance and electricity production capacity for application and development of solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Rahim, Mustamin [Department of Architecture, Khairun University, Ternate (Indonesia); Environmental and Renewable Energy Systems Division, Graduate School of Engineering, Gifu University (Japan); Yoshino, Jun; Yasuda, Takashi [Environmental and Renewable Energy Systems Division, Graduate School of Engineering, Gifu University (Japan)

    2012-07-01

    This study was undertaken to analyze solar radiation abundance to ascertain the potential of solar energy as an electrical energy resource. Local weather forecasting for predicting solar radiation is performed using a meteorological model MM5. The prediction results are compared with observed results obtained from the Japan Meteorological Agency for verification of the data accuracy. Results show that local weather forecasting has high accuracy. Prediction of solar radiation is similar with observation results. Monthly average values of solar radiation are sufficiently good during March–September. Electrical energy generated by photovoltaic cells is almost proportional to the solar radiation amount. Effects of clouds on solar radiation can be removed by monthly averaging. The balance between supply and demand of electricity can be estimated using a standard curve obtained from the temporal average. When the amount of solar radiation every hour with average of more than 100 km radius area does not yield the standard curve, we can estimate the system of storage and auxiliary power necessary based on the evaluated results of imbalance between supply and demand.

  16. Solar energy system with wind vane

    Energy Technology Data Exchange (ETDEWEB)

    Grip, Robert E

    2015-11-03

    A solar energy system including a pedestal defining a longitudinal axis, a frame that is supported by the pedestal and that is rotateable relative to the pedestal about the longitudinal axis, the frame including at least one solar device, and a wind vane operatively connected to the frame to urge the frame relative to the pedestal about the longitudinal axis in response to wind acting on the wind vane.

  17. Reliability engineering in solar energy: workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Gross, G.

    1980-03-01

    A workshop to reveal the scope of reliability-related activities in solar energy conversion projects and in nonsolar segments of industry is described. Two reliability programs, one in heating and cooling and one in photovoltaics, are explicated. This document also presents general suggestions for the establishment of a unified program for reliability, durability, maintainability, and safety (RDM and S) in present and future solar projects.

  18. Reliability engineering in solar energy: workshop proceedings

    Energy Technology Data Exchange (ETDEWEB)

    Gross, G.

    1980-03-01

    A workshop to reveal the scope of reliability-related activities in solar energy conversion projects and in nonsolar segments of industry is described. Two reliability programs, one in heating and cooling and one in photovoltaics, are explicated. This document also presents general suggestions for the establishment of a unified program for reliability, durability, maintainability, and safety (RDM and S) in present and future solar projects.

  19. Solar Energy Education. Home economics: student activities. Field test edition

    Energy Technology Data Exchange (ETDEWEB)

    1981-03-01

    A view of solar energy from the standpoint of home economics is taken in this book of activities. Students are provided information on solar energy resources while performing these classroom activities. Instructions for the construction of a solar food dryer and a solar cooker are provided. Topics for study include window treatments, clothing, the history of solar energy, vitamins from the sun, and how to choose the correct solar home. (BCS)

  20. 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)

  1. Solar Spots - Activities to Introduce Solar Energy into the K-8 Curricula.

    Science.gov (United States)

    Longe, Karen M.; McClelland, Michael J.

    Following an introduction to solar technology which reviews solar heating and cooling, passive solar systems (direct gain systems, thermal storage walls, sun spaces, roof ponds, and convection loops), active solar systems, solar electricity (photovoltaic and solar thermal conversion systems), wind energy, and biomass, activities to introduce solar…

  2. Phase change energy storage for solar dynamic power systems

    Science.gov (United States)

    Chiaramonte, F. P.; Taylor, J. D.

    1992-01-01

    This paper presents the results of a transient computer simulation that was developed to study phase change energy storage techniques for Space Station Freedom (SSF) solar dynamic (SD) power systems. Such SD systems may be used in future growth SSF configurations. Two solar dynamic options are considered in this paper: Brayton and Rankine. Model elements consist of a single node receiver and concentrator, and takes into account overall heat engine efficiency and power distribution characteristics. The simulation not only computes the energy stored in the receiver phase change material (PCM), but also the amount of the PCM required for various combinations of load demands and power system mission constraints. For a solar dynamic power system in low earth orbit, the amount of stored PCM energy is calculated by balancing the solar energy input and the energy consumed by the loads corrected by an overall system efficiency. The model assumes an average 75 kW SD power system load profile which is connected to user loads via dedicated power distribution channels. The model then calculates the stored energy in the receiver and subsequently estimates the quantity of PCM necessary to meet peaking and contingency requirements. The model can also be used to conduct trade studies on the performance of SD power systems using different storage materials.

  3. Materials science for solar energy conversion systems

    CERN Document Server

    Granqvist, CG

    1991-01-01

    Rapid advances in materials technology are creating many novel forms of coatings for energy efficient applications in solar energy. Insulating heat mirrors, selective absorbers, transparent insulation and fluorescent concentrators are already available commercially. Radiative cooling, electrochromic windows and polymeric light pipes hold promise for future development, while chemical and photochemical processes are being considered for energy storage. This book investigates new material advances as well as applications, costs, reliability and industrial production of existing materials. Each c

  4. Solar energy program evaluation: an introduction

    Energy Technology Data Exchange (ETDEWEB)

    deLeon, P.

    1979-09-01

    The Program Evaluation Methodology provides an overview of the practice and methodology of program evaluation and defines more precisely the evaluation techniques and methodologies that would be most appropriate to government organizations which are actively involved in the research, development, and commercialization of solar energy systems. Formal evaluation cannot be treated as a single methodological approach for assessing a program. There are four basic types of evaluation designs - the pre-experimental design; the quasi-experimental design based on time series; the quasi-experimental design based on comparison groups; and the true experimental design. This report is organized to first introduce the role and issues of evaluation. This is to provide a set of issues to organize the subsequent sections detailing the national solar energy programs. Then, these two themes are integrated by examining the evaluation strategies and methodologies tailored to fit the particular needs of the various individual solar energy programs. (MCW)

  5. The Texas Instruments Solar Energy System development

    Science.gov (United States)

    Johnson, E. L.

    The system is described, showing that energy conversion and storage functions are combined in a novel way. Here, small silicon solar cells are immersed in an electrolyte and the current generated by the cells is used directly to electrolyze a halogen acid, for example, HBr. The hydrogen and bromine produced can be stored separately until needed and then recombined in a fuel cell to give electrical energy on demand. The fuel cell HBr product is returned to the solar chemical convertor, thus completing the closed loop energy cycle. In summarizing the achievements to date, it is noted that feasibility demonstration of a 13% array electrical efficiency prepared by a laboratory process and 10% array efficiencies have been obtained from potentially scalable solar cell and array processes.

  6. Solar energy - When, where and how

    Science.gov (United States)

    Touryan, K. J.

    1981-05-01

    A comprehensive review is presented of the conversion technologies by which solar energy may be turned into useful end products. The degree of maturity of these technologies, which include photovoltaics, biomass conversion, and direct and indirect solar thermal conversion systems such as wind energy and ocean thermal gradients, ranges from those that are available commercially, such as hot water heating, to those that are in a robust embryonic stage, such as the production of ethanol from woody biomass. The cost, performance, market potential and environmental/social impact of these technologies are considered to determine (1) what fraction of the U.S. energy budget will be solar in the short, middle, and long terms, and (2) what the mix and distribution of these technologies will be in the year 2000.

  7. Surface Plasmon-Assisted Solar Energy Conversion.

    Science.gov (United States)

    Dodekatos, Georgios; Schünemann, Stefan; Tüysüz, Harun

    2016-01-01

    The utilization of localized surface plasmon resonance (LSPR) from plasmonic noble metals in combination with semiconductors promises great improvements for visible light-driven photocatalysis, in particular for energy conversion. This review summarizes the basic principles of plasmonic photocatalysis, giving a comprehensive overview about the proposed mechanisms for enhancing the performance of photocatalytically active semiconductors with plasmonic devices and their applications for surface plasmon-assisted solar energy conversion. The main focus is on gold and, to a lesser extent, silver nanoparticles in combination with titania as semiconductor and their usage as active plasmonic photocatalysts. Recent advances in water splitting, hydrogen generation with sacrificial organic compounds, and CO2 reduction to hydrocarbons for solar fuel production are highlighted. Finally, further improvements for plasmonic photocatalysts, regarding performance, stability, and economic feasibility, are discussed for surface plasmon-assisted solar energy conversion.

  8. Solar energy system economic evaluation for Solaron Akron, Akron, Ohio

    Science.gov (United States)

    1980-01-01

    The economic analysis of the solar energy system that was installed at Akron, Ohio is developed for this and four other sites typical of a wide range of environmental and economic conditions. The analysis is accomplished based on the technical and economic models in the f chart design procedure with inputs based on the characteristics of the installed parameters of present worth of system cost over a projected twenty year life: life cycle savings, year of positive savings and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables is also investigated. Results show that only in Albuquerque, New Mexico, where insolation is 1828 Btu/sq ft/day and the conventional energy cost is high, is this solar energy system marginally profitable.

  9. Solar Energy Research Center Instrumentation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Thomas, J.; Papanikolas, John, P.

    2011-11-11

    SOLAR ENERGY RESEARCH CENTER INSTRUMENTATION FACILITY The mission of the Solar Energy Research Center (UNC SERC) at the University of North Carolina at Chapel Hill (UNC-CH) is to establish a world leading effort in solar fuels research and to develop the materials and methods needed to fabricate the next generation of solar energy devices. We are addressing the fundamental issues that will drive new strategies for solar energy conversion and the engineering challenges that must be met in order to convert discoveries made in the laboratory into commercially available devices. The development of a photoelectrosynthesis cell (PEC) for solar fuels production faces daunting requirements: (1) Absorb a large fraction of sunlight; (2) Carry out artificial photosynthesis which involves multiple complex reaction steps; (3) Avoid competitive and deleterious side and reverse reactions; (4) Perform 13 million catalytic cycles per year with minimal degradation; (5) Use non-toxic materials; (6) Cost-effectiveness. PEC efficiency is directly determined by the kinetics of each reaction step. The UNC SERC is addressing this challenge by taking a broad interdisciplinary approach in a highly collaborative setting, drawing on expertise across a broad range of disciplines in chemistry, physics and materials science. By taking a systematic approach toward a fundamental understanding of the mechanism of each step, we will be able to gain unique insight and optimize PEC design. Access to cutting-edge spectroscopic tools is critical to this research effort. We have built professionally-staffed facilities equipped with the state-of the-art instrumentation funded by this award. The combination of staff, facilities, and instrumentation specifically tailored for solar fuels research establishes the UNC Solar Energy Research Center Instrumentation Facility as a unique, world-class capability. This congressionally directed project funded the development of two user facilities: TASK 1: SOLAR

  10. Artificial photosynthesis: biomimetic approaches to solar energy conversion and storage.

    Science.gov (United States)

    Kalyanasundaram, K; Graetzel, M

    2010-06-01

    Using sun as the energy source, natural photosynthesis carries out a number of useful reactions such as oxidation of water to molecular oxygen and fixation of CO(2) in the form of sugars. These are achieved through a series of light-induced multi-electron-transfer reactions involving chlorophylls in a special arrangement and several other species including specific enzymes. Artificial photosynthesis attempts to reconstruct these key processes in simpler model systems such that solar energy and abundant natural resources can be used to generate high energy fuels and restrict the amount of CO(2) in the atmosphere. Details of few model catalytic systems that lead to clean oxidation of water to H(2) and O(2), photoelectrochemical solar cells for the direct conversion of sunlight to electricity, solar cells for total decomposition of water and catalytic systems for fixation of CO(2) to fuels such as methanol and methane are reviewed here.

  11. Photovoltaic solar energy. Proceedings; Photovoltaische Solarenergie. Tagungsband

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    and limits (Mike Meinhardt); (17) Washing with the sun - Direct consumption of locally generated PV current by means of directed load shift in private households (Georg Bopp); (18) Efficiency by synergy. Export initiative renewable energies (Berthold Breid); (19) Modular PV power supply in the Empire of the Midth (Michael Wollny); (20) Breakthrough to a new era of PV hybrid systems with the help of standardised components communication? (Michael Mueller); (21) New PV stand-alone supply for frequency variable loads (Wolfgang Hernschier); (22) Characterization of solar batteries in long-term investigations according IEC 61427 (Wolfgang Wiesner); (23) Professional PV plant configuration - the status quo of the PV prpgrams (Mike Zehner); (24) Simulating renewable power projects with greenius{sup Free} (Volker Quaschning); (25) Analysis of the effect of shade and equivalent circuit of PV modules with the simulation software ''Solar Pro'' (Yusuke Mataki); (26) From data sheet values to the system gain - on realistic modelling of small PV generators (Hans Georg Beyer); (27) Form follows function - follows form function? - Ineractions between building functions and photovoltaic (Wolfgang Willkomm); (28) Market chances and technology perspectives for the Swiss facade construction by means of building integrated PV systems (Reto Miloni); (29) Passiv solar office building BIOHAUS Paderborn - architectonic overview and a first energy balance (Willi Ernst, Ralf Zirkler); (30) Building integration and education in Austria (Gernot Becker); (31) Photovoltaic and light (Thomas Herzog); (32) 10 years of test experience with the certification of design of photovoltaic modules (Andreas Cox); (32) Large size solar cells and the IEC 61215 - New challenges for the module junction (Eckehard Hofmueller); (33) Limits of power output optimisation of PV arrays by pre-sorting of PV modules (Werner Herrmann); (34) Coloured and patterned CIS modules (Dieter Geyer); (35) Energy

  12. Open cycle cooling systems using solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Lazzarin, R.; Sovrano, M.

    Open cycle cooling systems are particularly suitable for utilizing solar energy. In all these systems the adsorption and absorption phenomena are very important, hence they are described separately. The cycles used are essentially two: the Baum-Kakabaev cycle using liquid absorbers and the dehumidification/humidification cycle where also adsorbent substances can be utilized. Solar energy is used in the regeneration process of dehumidifying substances. Reactivation modes can be various: suitability of one mode or the other can depend on the climate of the site where the system is installed.

  13. Limits to solar and biomass energy growth

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, Y.M.; D' Alessio, G.J.

    1983-01-01

    Drawing on some 45 assessments made by the Technology Assessments of Solar Energy (TASE), the authors examine the potential for commercialization of solar and biomass technologies. The book is divided into four major parts: Part I describes and compares technologies; Part II describes the natural and capital resources necessary for commercialization; Part III examines social, economic, and environmental impacts and institutional and regulatory factors; and Part IV analyzes the consequences of several deployment scenarios. The authors conclude that the disproportionate resource requirements for a modest energy contribution will be liminting factor. 103 references, 80 figures, 32 tables. (DCK)

  14. Dye-sensitized Solar Cells for Solar Energy Harvesting

    Science.gov (United States)

    Roy, M. S.; Deol, Y. S.; Kumar, Manish; Prasad, Narottam; Janu, Yojana

    2011-10-01

    Dye-sensitized solar cells (DSSCs) also known as Gratzel cells, have attracted the interests of researchers to a great extent because of its cost effective and easy manufacturing process without involving highly sophisticated lithographic technique and high cost raw materials as usually seen in conventional solar cell. Based on simple photo-electrochemical process, it has got immense potential in converting solar energy to electrical power in remote and desert area where the supply of conventional power is not possible. The overall peak power-production efficiency of dye-sensitized solar cells has been reported around 11 percent, so they are best suited to low-density applications and the price-to-performance ratio obtained through these solar cells is superior to others. DSSCs have ability to absorb even diffused sunlight and therefore work in cloudy whether as well without much impact over the efficiency. The present communication deals with a review of our work on DSSCs wherein we have used cost effective natural dyes/pigments as a sensitizer of nc-TiO2 and discussed about various key factors affecting the conversion efficiency of DSSC.

  15. Adaptability of solar energy conversion systems on ships

    Science.gov (United States)

    Visa, I.; Cotorcea, A.; Neagoe, M.; Moldovan, M.

    2016-08-01

    International trade of goods largely uses maritime/transoceanic ships driven by engines using fossil fuels. This two centuries tradition is technologically mature but significantly adds to the CO2 emissions; therefore, recent trends focus on on-board implementation of systems converting the solar energy into power (photovoltaic systems) or heat (solar-thermal systems). These systems are carbon-emissions free but are still under research and plenty of effort is devoted to fast reach maturity and feasibility. Unlike the systems implemented in a specific continental location, the design of solar energy conversion systems installed on shipboard has to face the problem generated by the system base motion along with the ship travelling on routes at different latitudes: the navigation direction and sense and roll-pitch combined motion with reduced amplitude, but with relatively high frequency. These raise highly interesting challenges in the design and development of mechanical systems that support the maximal output in terms of electricity or heat. The paper addresses the modelling of the relative position of a solar energy conversion surface installed on a ship according to the current position of the sun; the model is based on the navigation trajectory/route, ship motion generated by waves and the relative sun-earth motion. The model describes the incidence angle of the sunray on the conversion surface through five characteristic angles: three used to define the ship orientation and two for the solar angles; based on, their influence on the efficiency in solar energy collection is analyzed by numerical simulations and appropriate recommendations are formulated for increasing the solar energy conversion systems adaptability on ships.

  16. Some analytic models of passive solar building performance: a theoretical approach to the design of energy-conserving buildings

    Energy Technology Data Exchange (ETDEWEB)

    Goldstein, D.B.

    1978-11-01

    This paper describes an application of the fundamental methods of physics to solve a problem of environmental and economic interest: the description of the thermal performance of passive solar buildings. Such a description is of great practical interest to building designers; however, this paper is not intended to be of use to architects and engineers in its present form. Its intention is to provide a theoretical basis for understanding passive solar buildings; further effort is needed to develop rules of solar engineering.

  17. Energy in Mexico: a profile of solar energy activity in its national context

    Energy Technology Data Exchange (ETDEWEB)

    Hawkins, D.

    1980-04-01

    The geopolitical, economic, and cultural aspects of the United States of Mexico are presented. Mexico's energy profile includes the following: energy policy objectives, government energy structure, organizations for implementation, indigeneous energy sources, imported energy sources, solar energy research and development, solar energy organizations and solar energy related legislation and administrative policies. International agreements, contacts, manufacturers, and projects are listed. (MRH)

  18. Urban air pollution and solar energy

    Science.gov (United States)

    Gammon, R. B.; Huning, J. R.; Reid, M. S.; Smith, J. H.

    1981-01-01

    The design and performance of solar energy systems for many potential applications (industrial/residential heat, electricity generation by solar concentration and photovoltaics) will be critically affected by local insolation conditions. The effects of urban air pollution are considered and reviewed. A study of insolation data for Alhambra, California (9 km south of Pasadena) shows that, during a recent second-stage photochemical smog alert (greater than or equal to 0.35 ppm ozone), the direct-beam insolation at solar noon was reduced by 40%, and the total global by 15%, from clean air values. Similar effects have been observed in Pasadena, and are attributable primarily to air pollution. Effects due to advecting smog have been detected 200 km away, in the Mojave Desert. Preliminary performance and economic simulations of solar thermal and photovoltaic power systems indicate increasing nonlinear sensitivity of life cycle plant cost to reductions in insolation levels due to pollution.

  19. Solar energy apparatus with apertured shield

    Science.gov (United States)

    Collings, Roger J. (Inventor); Bannon, David G. (Inventor)

    1989-01-01

    A protective apertured shield for use about an inlet to a solar apparatus which includesd a cavity receiver for absorbing concentrated solar energy. A rigid support truss assembly is fixed to the periphery of the inlet and projects radially inwardly therefrom to define a generally central aperture area through which solar radiation can pass into the cavity receiver. A non-structural, laminated blanket is spread over the rigid support truss in such a manner as to define an outer surface area and an inner surface area diverging radially outwardly from the central aperture area toward the periphery of the inlet. The outer surface area faces away from the inlet and the inner surface area faces toward the cavity receiver. The laminated blanket includes at least one layer of material, such as ceramic fiber fabric, having high infra-red emittance and low solar absorption properties, and another layer, such as metallic foil, of low infra-red emittance properties.

  20. Energy dissipation processes in solar wind turbulence

    CERN Document Server

    Wang, Y; Feng, X S; Xu, X J; Zhang, J; Sun, T R; Zuo, P B

    2015-01-01

    Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation cannot be ultimately achieved without collisions, and so how turbulent kinetic energy is dissipated in the nearly collisionless solar wind is a challenging problem. Wave particle interactions and magnetic reconnection are two possible dissipation mechanisms, but which mechanism dominates is still a controversial topic. Here we analyze the dissipation region scaling around a solar wind magnetic reconnection region. We find that the magnetic reconnection region shows a unique multifractal scaling in the dissipation range, while the ambient solar wind turbulence reveals a monofractal dissipation process for most of the time. These results provide the first observational evidences for the intermittent multifractal dissipation region scaling around a magnetic reconnection site, and they also have significant implications for the fundamental energy...

  1. ENERGY DISSIPATION PROCESSES IN SOLAR WIND TURBULENCE

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y.; Wei, F. S.; Feng, X. S.; Sun, T. R.; Zuo, P. B. [SIGMA Weather Group, State Key Laboratory for Space Weather, National Space Science Center, Chinese Academy of Sciences, Beijing 100190 (China); Xu, X. J. [Space Science Institute, Macau University of Science and Technology, Macao (China); Zhang, J., E-mail: yw@spaceweather.ac.cn [School of Physics, Astronomy and Computational Sciences, George Mason University, 4400 University Drive, MSN 3F3, Fairfax, Virginia 22030 (United States)

    2015-12-15

    Turbulence is a chaotic flow regime filled by irregular flows. The dissipation of turbulence is a fundamental problem in the realm of physics. Theoretically, dissipation ultimately cannot be achieved without collisions, and so how turbulent kinetic energy is dissipated in the nearly collisionless solar wind is a challenging problem. Wave particle interactions and magnetic reconnection (MR) are two possible dissipation mechanisms, but which mechanism dominates is still a controversial topic. Here we analyze the dissipation region scaling around a solar wind MR region. We find that the MR region shows unique multifractal scaling in the dissipation range, while the ambient solar wind turbulence reveals a monofractal dissipation process for most of the time. These results provide the first observational evidences for intermittent multifractal dissipation region scaling around a MR site, and they also have significant implications for the fundamental energy dissipation process.

  2. Geostellar: Remote Solar Energy Assessments Personalized

    Energy Technology Data Exchange (ETDEWEB)

    2015-10-01

    Geostellar has produced an online tool that generates a unique solar profile for homeowners to learn about the financial benefits to installing rooftop solar panels on their home. The website incorporates the physical building characteristics of the home, including shading, slope, and orientation of the roof, and applies electricity costs and incentives to determine the best solar energy estimated energy production values against actual installed rooftop photovoltaic systems. The validation conducted by NREL concluded that over three-quarters of Geostellar's potential size estimates are at least as large as the actual installed systems, indicating a correct assessment of roof availability. In addition, 87% of Geostellar's 25-year production estimates are within 90% of the actual PV Watts results.

  3. Luminescent solar concentrators and all-inorganic nanoparticle solar cells for solar energy harvesting

    Science.gov (United States)

    Sholin, Veronica

    Increasing energy demand and the parallel increase of greenhouse gas emissions are challenging researchers to find new and cleaner energy sources. Solar energy harvesting is arguably the most promising candidate for replacing fossil-fuel power generation. Photovoltaics are the most direct way of collecting solar energy; cost continues to hinder large-scale implementation of photovoltaics, however. Therefore, alternative technologies that will allow the extraction of solar power, while maintaining the overall costs of fabrication, installation, collection, and distribution low, must be explored. This thesis focuses on the fabrication and testing of two types of devices that step up to this challenge: the luminescent solar concentrator (LSC) and all-inorganic nanoparticle solar cells. In these devices I make use of novel materials, semiconducting polymers and inorganic nanoparticles, both of which have lower costs than the crystalline materials used in the fabrication of traditional photovoltaics. Furthermore, the cost of manufacturing LSCs and the nanoparticle solar cells is lower than the manufacturing cost of traditional optics-based concentrators and crystalline solar cells. An LSC is essentially a slab of luminescent material that acts as a planar light pipe. The LSC absorbs incoming photons and channels fluoresced photons toward appropriately located solar cells, which perform the photovoltaic conversion. By covering large areas with relatively inexpensive fluorescing organic dyes or semiconducting polymers, the area of solar cell needed is greatly reduced. Because semiconducting polymers and quantum dots may have small absorption/emission band overlaps, tunable absorption, and longer lifetimes, they are good candidates for LSC fabrication, promising improvement with respect to laser dyes traditionally used to fabricate LSCs. Here the efficiency of LSCs consisting of liquid solutions of semiconducting polymers encased in glass was measured and compared to the

  4. Thermochemical process for seasonal storage of solar energy: characterization and modeling of a high-density reactive bed

    OpenAIRE

    Michel, Benoit; Mazet, Nathalie; Mauran, Sylvain; Stitou, Driss; Jing XU

    2012-01-01

    International audience; This paper focuses on the characterization and modeling of a solid/gas thermochemical reaction between a porous reactive bed and moist air flowing through it. The aim is the optimization of both energy density and permeability of the reactive bed, in order to realize a high density thermochemical system for seasonal thermal storage for house heating application. Several samples with different implementation parameters (density, binder, diffuser, porous bed texture) hav...

  5. Energy transfer processes in solar energy conversion

    Energy Technology Data Exchange (ETDEWEB)

    Fayer, M.D.

    1986-11-01

    By combining picosecond optical experiments and detailed statistical mechanics theory we continue to increase our understanding of the complex interplay of structure and dynamics in important energy transfer situations. A number of different types of problems will be focused on experimentally and theoretically. They are excitation transport among chromophores attached to finite size polymer coils; excitation transport among chromophores in monolayers, bilayers, and finite and infinite stacks of layers; excitation transport in large vesicle systems; and photoinduced electron transfer in glasses and liquids, focusing particularly on the back transfer of the electron from the photogenerated radical anion to the radical cation. 33 refs., 13 figs.

  6. Solar Energy Education. Reader, Part II. Sun story. [Includes glossary

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    Magazine articles which focus on the subject of solar energy are presented. The booklet prepared is the second of a four part series of the Solar Energy Reader. Excerpts from the magazines include the history of solar energy, mythology and tales, and selected poetry on the sun. A glossary of energy related terms is included. (BCS)

  7. Wind loads on solar energy roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van

    2007-01-01

    This paper presents an overview of the wind loads on roofs, equipped with solar energy products, so called Active Roofs. Values given in this paper have been based on wind tunnel and full scale measurements, carried out at TNO, and on an interpretation of existing rules and guidelines. The results a

  8. Solar electric power generation photovoltaic energy systems

    CERN Document Server

    Krauter, Stefan CW

    2007-01-01

    Solar electricity is a viable, environmentally sustainable alternative to the world's energy supplies. In support, this work examines the various technical parameters of photovoltaic systems. It analyzes the study of performance and yield (including optical, thermal, and electrical parameters and interfaces).

  9. Utilization of solar energy in South Africa

    CSIR Research Space (South Africa)

    Whillier, A

    1953-04-01

    Full Text Available Design curves based on measurements of solar irradiation in South Africa are presented for two geographic areas, the highveld and the Cape Peninsula, giving data on the amount of thermal energy that can be collected from the sun by use of flat...

  10. Solar Energy Education. Reader, Part IV. Sun schooling

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    A collection of magazine articles which focus on solar energy is presented. This is the final book of the four part series of the Solar Energy Reader. The articles include brief discussions on energy topics such as the sun, ocean energy, methane gas from cow manure, and solar homes. Instructions for constructing a sundial and a solar stove are also included. A glossary of energy related terms is provided. (BCS)

  11. Solar energy utilization by physical methods.

    Science.gov (United States)

    Wolf, M

    1974-04-19

    On the basis of the estimated contributions of these differing methods of the utilization of solar energy, their total energy delivery impact on the projected U.S. energy economy (9) can be evaluated (Fig. 5). Despite this late energy impact, the actual sales of solar energy utilization equipment will be significant at an early date. Potential sales in photovoltaic arrays alone could exceed $400 million by 1980, in order to meet the projected capacity buildup (10). Ultimately, the total energy utilization equipment industry should attain an annual sales volume of several tens of billion dollars in the United States, comparable to that of several other energy related industries. Varying amounts of technology development are required to assure the technical and economic feasibility of the different solar energy utilization methods. Several of these developments are far enough along that the paths can be analyzed from the present time to the time of demonstration of technical and economic feasibility, and from there to production and marketing readiness. After that point, a period of market introduction will follow, which will differ in duration according to the type of market addressed. It may be noted that the present rush to find relief from the current energy problem, or to be an early leader in entering a new market, can entail shortcuts in sound engineering practice, particularly in the areas of design for durability and easy maintenance, or of proper application engineering. The result can be loss of customer acceptance, as has been experienced in the past with various products, including solar water heaters. Since this could cause considerable delay in achieving the expected total energy impact, it will be important to spend adequate time at this stage for thorough development. Two other aspects are worth mentioning. The first is concerned with the economic impacts. Upon reflection on this point, one will observe that largescale solar energy utilization will

  12. Fluid circulating pump operated by same incident solar energy which heats energy collection fluid

    Science.gov (United States)

    Collins, E. R.

    1980-01-01

    The application of using a spacecraft solar powered pump terrestrially to reduce or eliminate the need for fossil fuel generated electricity for domestic solar hot water systems was investigated. A breadboard prototype model was constructed utilizing bimetals to convert thermal energy into mechanical motion by means of a toggle operated shutter mechanism. Although it did not meet expected thermal efficiency, the prototype model was sufficient to demonstrate the mechanical concept.

  13. Solar energy system economic evaluation: IBM System 2, Togus, Maine

    Science.gov (United States)

    1980-01-01

    The economic analysis of the solar energy system, is developed for Torgus and four other sites typical of a wide range of environmental and economic conditions in the continental United States. This analysis is accomplished based on the technical and economic models in the f-chart design procedure with inputs taken on the characteristics of the installed system and local conditions. The results are expressed in terms of the economic parameters of present worth of system cost over a projected twenty year life, life cycle savings, year of positive savings and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables is also investigated. Results demonstrate that the solar energy system is economically viable at all of the five sites for which the analysis was conducted.

  14. Technology Roadmaps: Solar photovoltaic energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    Solar PV power is a commercially available and reliable technology with a significant potential for long-term growth in nearly all world regions. This roadmap estimates that by 2050, PV will provide around 11% of global electricity production and avoid 2.3 gigatonnes (Gt) of CO2 emissions per year. Achieving this roadmap's vision will require an effective, long-term and balanced policy effort in the next decade to allow for optimal technology progress, cost reduction and ramp-up of industrial manufacturing for mass deployment. Governments will need to provide long-term targets and supporting policies to build confidence for investments in manufacturing capacity and deployment of PV systems. PV will achieve grid parity -- i.e. competitiveness with electricity grid retail prices -- by 2020 in many regions. As grid parity is achieved, the policy framework should evolve towards fostering self-sustained markets, with the progressive phase-out of economic incentives, but maintaining grid access guarantees and sustained R&D support.

  15. Development of a Conceptual Structure for Architectural Solar Energy Systems.

    Science.gov (United States)

    Ringel, Robert F.

    Solar subsystems and components were identified and conceptual structure was developed for architectural solar energy heating and cooling systems. Recent literature related to solar energy systems was reviewed and analyzed. Solar heating and cooling system, subsystem, and component data were compared for agreement and completeness. Significant…

  16. Chalcogenide Perovskites for Solar Energy Harvesting

    Science.gov (United States)

    Perera, Samanthe

    Methylammonium Lead halide perovskites have recently emerged as a promising candidate for realizing high efficient low cost photovoltaic modules. Charge transport properties of the solution processed halide perovskites are comparable to some of the existing absorbers used in the current PV industry which require sophisticated processing techniques. Due to this simple processing required to achieve high efficiencies, halide perovskites have become an active field of research. As a result, perovskite solar cells are rapidly reaching towards theoretical efficiency limit of close to 30%. It's believed that ionicity inherent to perovskite materials is one of the contributing factors for the excellent charge transport properties of perovskites. Despite the growing interest for solar energy harvesting purposes, these halide perovskites have serious limitations such as toxicity and instability that need to be addressed in order to commercialize the solar cells incorporating them. This dissertation focuses on a new class of ionic semiconductors, chalcogenide perovskites for solar energy harvesting purposes. Coming from the family perovskites they are expected to have same excellent charge transport properties inherent to perovskites due to the ionicity. Inspired by few theoretical studies on chalcogenide perovskites, BaZrS3 and its Ti alloys were synthesized by sulfurizing the oxide counterpart. Structural characterizations have confirmed the predicted distorted perovskite phase. Optical characterizations have verified the direct band gap suitable for thin film single junction solar cells. Anion alloying was demonstrated by synthesizing oxysulfides with widely tunable band gap suitable for applications such as solid state lighting and sensing.

  17. Sustainability and economics: The Adirondack Park experience, a forest economic-ecological model, and solar energy policy

    Science.gov (United States)

    Erickson, Jon David

    The long-term sustainability of human communities will depend on our relationship with regional environments, our maintenance of renewable resources, and our successful disengagement from nonrenewable energy dependence. This dissertation investigates sustainability at these three levels, following a critical analysis of sustainability and economics. At the regional environment level, the Adirondack Park of New York State is analyzed as a potential model of sustainable development. A set of initial and ongoing conditions are presented that both emerge from and support a model of sustainability in the Adirondacks. From these conditions, a clearer picture emerges of the definition of regional sustainability, consequences of its adoption, and lessons from its application. Next, an economic-ecological model of the northern hardwood forest ecosystem is developed. The model integrates economic theory and intertemporal ecological concepts, linking current harvest decisions with future forest growth, financial value, and ecosystem stability. The results indicate very different economic and ecological outcomes by varying opportunity cost and ecosystem recovery assumptions, and suggest a positive benefit to ecological recovery in the forest rotation decision of the profit maximizing manager. The last section investigates the motives, economics, and international development implications of renewable energy (specifically photovoltaic technology) in rural electrification and technology transfer, drawing on research in the Dominican Republic. The implications of subsidizing a photovoltaic market versus investing in basic research are explored.

  18. Development of three-dimensional magnetohydrodynamic model for solar corona and solar wind simulation

    Science.gov (United States)

    Yuan, Xingqiu; Trichtchenko, Larisa; Boteler, David

    Propagation of coronal mass ejections from solar surface to the Earth magnetosphere is strongly influenced by the conditions in solar corona and ambient solar wind. Thus, reliable simulation of the background solar wind is the primary task toward the development of numerical model for the transient events. In this paper we introduce a new numerical model which has been specifically designed for numerical study of the solar corona and ambient solar wind. This model is based on our recently developed three-dimensional Spherical Coordinate Adaptive Magneto-Hydro-Dynamic (MHD) code (SCA-MHD-3D) [Yuan et al., 2009]. Modifications has been done to include the observed magnetic field at the photosphere as inner boundary conditions. The energy source term together with reduced plasma gamma are used in the nonlinear MHD equations in order to simulate the solar wind acceleration from subsonic speed at solar surface to supersonic speed at the inter-heliosphere region, and the absorbing boundary conditions are used at the solar surface. This model has been applied to simulate the background solar wind condition for several different solar rotations, and comparison between the observation and model output have shown that it reproduces many features of solar wind, including open and closed magnetic fields, fast and slow solar wind speed, sector boundaries, etc.

  19. Solar energy conversion systems engineering and economic analysis radiative energy input/thermal electric output computation. Volume III

    Energy Technology Data Exchange (ETDEWEB)

    Russo, G.

    1982-09-01

    The direct energy flux analytical model, an analysis of the results, and a brief description of a non-steady state model of a thermal solar energy conversion system implemented on a code, SIRR2, as well as the coupling of CIRR2 which computes global solar flux on a collector and SIRR2 are presented. It is shown how the CIRR2 and, mainly, the SIRR2 codes may be used for a proper design of a solar collector system. (LEW)

  20. Near-term Forecasting of Solar Total and Direct Irradiance for Solar Energy Applications

    Science.gov (United States)

    Long, C. N.; Riihimaki, L. D.; Berg, L. K.

    2012-12-01

    Integration of solar renewable energy into the power grid, like wind energy, is hindered by the variable nature of the solar resource. One challenge of the integration problem for shorter time periods is the phenomenon of "ramping events" where the electrical output of the solar power system increases or decreases significantly and rapidly over periods of minutes or less. Advance warning, of even just a few minutes, allows power system operators to compensate for the ramping. However, the ability for short-term prediction on such local "point" scales is beyond the abilities of typical model-based weather forecasting. Use of surface-based solar radiation measurements has been recognized as a likely solution for providing input for near-term (5 to 30 minute) forecasts of solar energy availability and variability. However, it must be noted that while fixed-orientation photovoltaic panel systems use the total (global) downwelling solar radiation, tracking photovoltaic and solar concentrator systems use only the direct normal component of the solar radiation. Thus even accurate near-term forecasts of total solar radiation will under many circumstances include inherent inaccuracies with respect to tracking systems due to lack of information of the direct component of the solar radiation. We will present examples and statistical analyses of solar radiation partitioning showing the differences in the behavior of the total/direct radiation with respect to the near-term forecast issue. We will present an overview of the possibility of using a network of unique new commercially available total/diffuse radiometers in conjunction with a near-real-time adaptation of the Shortwave Radiative Flux Analysis methodology (Long and Ackerman, 2000; Long et al., 2006). The results are used, in conjunction with persistence and tendency forecast techniques, to provide more accurate near-term forecasts of cloudiness, and both total and direct normal solar irradiance availability and

  1. Nanophysics of solar and renewable energy

    CERN Document Server

    Wolf, Edward L

    2012-01-01

    This easy accessible textbook provides an overview of solar to electric energy conversion, followed by a detailed look at one aspect, namely photovoltaics, including the underlying principles and fabrication methods. Professor Wolf, an experienced author and teacher, reviews such green technologies as solar-heated-steam power, hydrogen, and ""artificial leaf"" approaches, as well as nuclear fusion. Throughout the book, carefully chosen, up-to-date examples are used to illustrate important concepts and research tools.The opening chapters give a broad and exhaustive survey of long term energ

  2. Adaptive control of solar energy collector systems

    CERN Document Server

    Lemos, João M; Igreja, José M

    2014-01-01

    This book describes methods for adaptive control of distributed-collector solar fields: plants that collect solar energy and deliver it in thermal form. Controller design methods are presented that can overcome difficulties found in these type of plants:they are distributed-parameter systems, i.e., systems with dynamics that depend on space as well as time;their dynamics is nonlinear, with a bilinear structure;there is a significant level of uncertainty in plant knowledge.Adaptive methods form the focus of the text because of the degree of uncertainty in the knowledge of plant dynamics. Parts

  3. Solar gravitational energy and luminosity variations

    CERN Document Server

    Fazel, Z; Lefebvre, S; Ajabshirizadeh, A; Pireaux, S; 10.1016/j.newst.2007.05.003

    2009-01-01

    Due to non-homogeneous mass distribution and non-uniform velocity rate inside the Sun, the solar outer shape is distorted in latitude. In this paper, we analyze the consequences of a temporal change in this figure on the luminosity. To do so, we use the Total Solar Irradiance (TSI) as an indicator of luminosity. Considering that most of the authors have explained the largest part of the TSI modulation with magnetic network (spots and faculae) but not the whole, we could set constraints on radius and effective temperature variations (dR, dT). However computations show that the amplitude of solar irradiance modulation is very sensitive to photospheric temperature variations. In order to understand discrepancies between our best fit and recent observations of Livingston et al. (2005), showing no effective surface temperature variation during the solar cycle, we investigated small effective temperature variation in irradiance modeling. We emphasized a phase-shift (correlated or anticorrelated radius and irradianc...

  4. Renewable Energy: Solar Fuels GRC and GRS

    Energy Technology Data Exchange (ETDEWEB)

    Lewis, Nathan [California Inst. of Technology (CalTech), Pasadena, CA (United States); Gray, Nancy Ryan [Gordon Research Conferences, West Kingston, RI (United States)

    2010-02-26

    sources from a carbon-neutral source. Sunlight is by far the most abundant global carbon-neutral energy resource. More solar energy strikes the surface of the earth in one hour than is obtained from all of the fossil fuels consumed globally in a year. Sunlight may be used to power the planet. However, it is intermittent, and therefore it must be converted to electricity or stored chemical fuel to be used on a large scale. The 'grand challenge' of using the sun as a future energy source faces daunting challenges - large expanses of fundamental science and technology await discovery. A viable solar energy conversion scheme must result in a 10-50 fold decrease in the cost-to-efficiency ratio for the production of stored fuels, and must be stable and robust for a 20-30 year period. To reduce the cost of installed solar energy conversion systems to $0.20/peak watt of solar radiation, a cost level that would make them economically attractive in today's energy market, will require revolutionary technologies. This GRC seeks to present a forum for the underlying science needed to permit future generations to use the sun as a renewable and sustainable primary energy source. Speakers will discuss recent advances in homoogeneous and heterogeneous catalysis of multi-electron transfer processes of importance to solar fuel production, such as water oxidation and reduction, and carbon dioxide reduction. Speakers will also discuss advances in scaleably manufacturable systems for the capture and conversion of sunlight into electrical charges that can be readily coupled into, and utilized for, fuel production in an integrated system.

  5. Energy modelling software

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available The construction industry has turned to energy modelling in order to assist them in reducing the amount of energy consumed by buildings. However, while the energy loads of buildings can be accurately modelled, energy models often under...

  6. Efficient conversion of solar energy to biomass and electricity.

    Science.gov (United States)

    Parlevliet, David; Moheimani, Navid Reza

    2014-01-01

    The Earth receives around 1000 W.m(-2) of power from the Sun and only a fraction of this light energy is able to be converted to biomass (chemical energy) via the process of photosynthesis. Out of all photosynthetic organisms, microalgae, due to their fast growth rates and their ability to grow on non-arable land using saline water, have been identified as potential source of raw material for chemical energy production. Electrical energy can also be produced from this same solar resource via the use of photovoltaic modules. In this work we propose a novel method of combining both of these energy production processes to make full utilisation of the solar spectrum and increase the productivity of light-limited microalgae systems. These two methods of energy production would appear to compete for use of the same energy resource (sunlight) to produce either chemical or electrical energy. However, some groups of microalgae (i.e. Chlorophyta) only require the blue and red portions of the spectrum whereas photovoltaic devices can absorb strongly over the full range of visible light. This suggests that a combination of the two energy production systems would allow for a full utilization of the solar spectrum allowing both the production of chemical and electrical energy from the one facility making efficient use of available land and solar energy. In this work we propose to introduce a filter above the algae culture to modify the spectrum of light received by the algae and redirect parts of the spectrum to generate electricity. The electrical energy generated by this approach can then be directed to running ancillary systems or producing extra illumination for the growth of microalgae. We have modelled an approach whereby the productivity of light-limited microalgae systems can be improved by at least 4% through using an LED array to increase the total amount of illumination on the microalgae culture.

  7. Optimization of a solar cooling system with interior energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Sanjuan, C.; Soutullo, S.; Heras, M.R. [Department of Energy, Energy Efficiency in Buildings Unit, CIEMAT, Madrid E-28040 (Spain)

    2010-07-15

    This paper focuses on the optimization of the performance of a solar absorption cooling system composed by four units with interior energy storage. A full dynamic simulation model that includes the solar collector field, the absorption heat pump system and the building load calculation has been developed. It has been applied to optimize the coupling of a system based on this new technology of solar powered absorption heat pump, to a bioclimatic building recently constructed in the Plataforma Solar de Almeria (PSA) in Spain. The absorption heat pump system considered is composed by four heat pumps that store energy in the form of crystallized salts so that no external storage capacity is required. Each heat pump is composed of two separate barrels that can charge (store energy from the solar field) and discharge (deliver heat or cold to the building) independently. Different configurations of the four units have been analysed taking into account the storage possibilities of the system and its capacity to respond to the building loads. It has been shown how strong the influence of the control strategies in the overall performance is, and the importance of using hourly simulations models when looking for highly efficient buildings. (author)

  8. Tandem photovoltaic solar cells and increased solar energy conversion efficiency

    Science.gov (United States)

    Loferski, J. J.

    1976-01-01

    Tandem photovoltaic cells, as proposed by Jackson (1955) to increase the efficiency of solar energy conversion, involve the construction of a system of stacked p/n homojunction photovoltaic cells composed of different semiconductors. It had been pointed out by critics, however, that the total power which could be extracted from the cells in the stack placed side by side was substantially greater than the power obtained from the stacked cells. A reexamination of the tandem cell concept in view of the development of the past few years is conducted. It is concluded that the use of tandem cell systems in flat plate collectors, as originally envisioned by Jackson, may yet become feasible as a result of the development of economically acceptable solar cells for large scale terrestrial power generation.

  9. Tandem photovoltaic solar cells and increased solar energy conversion efficiency

    Science.gov (United States)

    Loferski, J. J.

    1976-01-01

    Tandem photovoltaic cells, as proposed by Jackson (1955) to increase the efficiency of solar energy conversion, involve the construction of a system of stacked p/n homojunction photovoltaic cells composed of different semiconductors. It had been pointed out by critics, however, that the total power which could be extracted from the cells in the stack placed side by side was substantially greater than the power obtained from the stacked cells. A reexamination of the tandem cell concept in view of the development of the past few years is conducted. It is concluded that the use of tandem cell systems in flat plate collectors, as originally envisioned by Jackson, may yet become feasible as a result of the development of economically acceptable solar cells for large scale terrestrial power generation.

  10. Annual energy yield of the fluorescent solar concentrator

    Energy Technology Data Exchange (ETDEWEB)

    Van Sark, W.G.J.H.M.; Hellenbrand, G.F.M.G. [Department of Science, Technology and Society, Copernicus Institute for Sustainable Development and Innovation, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht (Netherlands); Bende, E.E.; Burgers, A.R.; Slooff, L.H. [ECN Solar Energy, P.O. Box 1, 1755 ZG Petten (Netherlands)

    2008-09-15

    Fluorescent solar concentrators are but one candidate for lowering the costs of photovoltaic technology. State-of-the-art device conversion efficiencies are around 4%, and the device configuration can be optimized in terms of Euro per Watt. This paper aims to estimate the annual energy yield of such an optimized device configuration, using a detailed minutely spectral irradiance data set, describing a full year in the Netherlands, in combination with a ray-tracing model of the fluorescent solar concentrator. The spectral dataset is modeled using experimentally determined global, direct, and diffuse irradiation data on a minutely basis. Performance variations during the day for a number of typical days are investigated, i.e., for a clear summer day, a cloudy summer day, a clear winter day, and a cloudy winter day, using a ray-trace model of the fluorescent solar concentrator. Also, monthly aggregated spectra are used, as well as an annually aggregated spectrum to determine monthly and annual energy yields, respectively. As a result of a cost-per-unit-of-power optimization study, an optimum size of 23x23x0.1 cm{sup 3} was used, and an annual energy yield of 41.3 kWh/m{sup 2} could be estimated; this is 4.7 times lower than the annual energy yield of a state-of-the-art silicon solar cell.

  11. Solar energy converter using surface plasma waves

    Science.gov (United States)

    Anderson, L. M. (Inventor)

    1984-01-01

    Sunlight is dispersed over a diffraction grating formed on the surface of a conducting film on a substrate. The angular dispersion controls the effective grating period so that a matching spectrum of surface plasmons is excited for parallel processing on the conducting film. The resulting surface plasmons carry energy to an array of inelastic tunnel diodes. This solar energy converter does not require different materials for each frequency band, and sunlight is directly converted to electricity in an efficient manner by extracting more energy from the more energetic photons.

  12. Solar energy legal bibliography. Final report. [160 references

    Energy Technology Data Exchange (ETDEWEB)

    Seeley, D.; Euser, B.; Joyce, C.; Morgan, G. H.; Laitos, J. G.; Adams, A.

    1979-03-01

    The Solar Energy Legal Bibliography is a compilation of approximately 160 solar publications abstracted for their legal and policy content (through October 1978). Emphasis is on legal barriers and incentives to solar energy development. Abstracts are arranged under the following categories: Antitrust, Biomass, Building Codes, Consumer Protection, Environmental Aspects, Federal Legislation and Programs, Financing/Insurance, International Law, Labor, Land Use (Covenants, Easements, Nuisance, Zoning), Local Legislation and Programs, Ocean Energy, Patents and Licenses, Photovoltaics, Solar Access Rights, Solar Heating and Cooling, Solar Thermal Power Systems, Standards, State Legislation and Programs, Tax Law, Tort Liability, Utilities, Warranties, Wind Resources, and General Solar Law.

  13. Solar models and solar neutrino oscillations

    OpenAIRE

    2004-01-01

    We provide a summary of the current knowledge, theoretical and experimental, of solar neutrino fluxes and of the masses and mixing angles that characterize solar neutrino oscillations. We also summarize the principal reasons for doing new solar neutrino experiments and what we think may be learned from the future measurements.

  14. Solar energy in Italy: a profile of renewable energy activity in its national context

    Energy Technology Data Exchange (ETDEWEB)

    Shea, C.A.

    1980-12-01

    The following are included: country overview; energy summary; Italian Republic-geopolitical, economic, and cultural aspects; the energy profile; imported energy sources; solar energy research and development; solar energy organizations; solar energy related legislation and administration policies; and international agreements, contacts, manufacturers, and projects. (MHR)

  15. Solar energy, conservation, and rental housing

    Energy Technology Data Exchange (ETDEWEB)

    Levine, A.; Raab, J.

    1981-03-01

    Renters must pay the majority of energy costs either directly or in their rents. They have limited financial and legal abilities to make improvements necessary to increase substantially the energy efficiency of rental housing. This report discusses the problem of how to increase investments in energy conservation and solar energy devices for rental housing, which constitutes over one-third of US housing. As background, this report characterizes the rental-housing market, including owners' decision-making criteria. Federal, state, and local policies that affect energy-related investments in rental housing are described. Programs are divided into five major categories: (1) programs for tenants, (2) financial incentives for owners, (3) leasing of solar energy equipment, (4) mediation between tenants and landlords, and (5) regulation. The report concludes that energy and conservation programs aimed at the residential sector must disaggregate owner-occupied housing from rental housing for maximum effect. No one program is advocated since local rental-housing markets differ substantially. For improvements greater than no-cost or low-cost items, programs must be directed at rental-housing owners and not only at tenants.

  16. Solar energy in the context of energy use, energy transportation and energy storage.

    Science.gov (United States)

    MacKay, David J C

    2013-08-13

    Taking the UK as a case study, this paper describes current energy use and a range of sustainable energy options for the future, including solar power and other renewables. I focus on the area involved in collecting, converting and delivering sustainable energy, looking in particular detail at the potential role of solar power. Britain consumes energy at a rate of about 5000 watts per person, and its population density is about 250 people per square kilometre. If we multiply the per capita energy consumption by the population density, then we obtain the average primary energy consumption per unit area, which for the UK is 1.25 watts per square metre. This areal power density is uncomfortably similar to the average power density that could be supplied by many renewables: the gravitational potential energy of rainfall in the Scottish highlands has a raw power per unit area of roughly 0.24 watts per square metre; energy crops in Europe deliver about 0.5 watts per square metre; wind farms deliver roughly 2.5 watts per square metre; solar photovoltaic farms in Bavaria, Germany, and Vermont, USA, deliver 4 watts per square metre; in sunnier locations, solar photovoltaic farms can deliver 10 watts per square metre; concentrating solar power stations in deserts might deliver 20 watts per square metre. In a decarbonized world that is renewable-powered, the land area required to maintain today's British energy consumption would have to be similar to the area of Britain. Several other high-density, high-consuming countries are in the same boat as Britain, and many other countries are rushing to join us. Decarbonizing such countries will only be possible through some combination of the following options: the embracing of country-sized renewable power-generation facilities; large-scale energy imports from country-sized renewable facilities in other countries; population reduction; radical efficiency improvements and lifestyle changes; and the growth of non-renewable low

  17. Solar PV Energy Conversion System and its Configurations

    OpenAIRE

    Ahteshamul Haque

    2016-01-01

    Solar PV based energy conversion system is now used in commercial and residential buildings. Advancements in Power electronics leads the researchers to enhance the use of solar application in various configurations. These configurations may be used to utilize the energy optimally. The main objective of this paper is to present an overview of the various configurations of solar PV energy conversion system

  18. Solar Energy Education. Renewable energy activities for junior high/middle school science

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    Some basic topics on the subject of solar energy are outlined in the form of a teaching manual. The manual is geared toward junior high or middle school science students. Topics include solar collectors, solar water heating, solar radiation, insulation, heat storage, and desalination. Instructions for the construction of apparatus to demonstrate the solar energy topics are provided. (BCS)

  19. Solar Energy Education. Reader, Part I. Energy, Society, and the Sun

    Energy Technology Data Exchange (ETDEWEB)

    1981-05-01

    A collection of magazine articles which were selected for information on solar energy is presented in this booklet. This booklet is the first of a four part series of the Solar Energy Reader. The articles provide brief discussions on topics such as the power of the sun, solar energy developments for homes, solar energy versus power plants, solar access laws, and the role of utilities with respect to the sun's energy. (BCS)

  20. Economical solar-heating or cooling system with new solar-energy concentrators

    Science.gov (United States)

    Shimada, K.

    1975-01-01

    Economical solar energy collector, made from array of cylindrical Fresnel lenses, does not require tracking mechanism. As the sun changes position, lenses focus solar energy on different collector elements.

  1. Solar hybrid power plants: Solar energy contribution in reaching full dispatchability and firmness

    Science.gov (United States)

    Servert, Jorge F.; López, Diego; Cerrajero, Eduardo; Rocha, Alberto R.; Pereira, Daniel; Gonzalez, Lucía

    2016-05-01

    Renewable energies for electricity generation have always been considered as a risk for the electricity system due to its lack of dispatchability and firmness. Renewable energies penetration is constrained to strong grids or else its production must be limited to ensure grid stability, which is kept by the usage of hydropower energy or fossil-fueled power plants. CSP technology has an opportunity to arise not only as a dispatchable and firm technology, but also as an alternative that improves grid stability. To achieve that objective, solar hybrid configurations are being developed, being the most representative three different solutions: SAPG, ISCC and HYSOL. A reference scenario in Kingdom of Saudi Arabia (KSA) has been defined to compare these solutions, which have been modelled, simulated and evaluated in terms of dispatchability and firmness using ratios defined by the authors. The results show that: a) SAPG obtains the highest firmness KPI values, but no operation constraints have been considered for the coal boiler and the solar energy contribution is limited to 1.7%, b) ISCC provides dispatchable and firm electricity production but its solar energy contribution is limited to a 6.4%, and c) HYSOL presents the higher solar energy contribution of all the technologies considered: 66.0% while providing dispatchable and firm generation in similar conditions as SAPG and ISCC.

  2. Solar Energy Research Center Instrumentation Facility

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, Thomas, J.; Papanikolas, John, P.

    2011-11-11

    SOLAR ENERGY RESEARCH CENTER INSTRUMENTATION FACILITY The mission of the Solar Energy Research Center (UNC SERC) at the University of North Carolina at Chapel Hill (UNC-CH) is to establish a world leading effort in solar fuels research and to develop the materials and methods needed to fabricate the next generation of solar energy devices. We are addressing the fundamental issues that will drive new strategies for solar energy conversion and the engineering challenges that must be met in order to convert discoveries made in the laboratory into commercially available devices. The development of a photoelectrosynthesis cell (PEC) for solar fuels production faces daunting requirements: (1) Absorb a large fraction of sunlight; (2) Carry out artificial photosynthesis which involves multiple complex reaction steps; (3) Avoid competitive and deleterious side and reverse reactions; (4) Perform 13 million catalytic cycles per year with minimal degradation; (5) Use non-toxic materials; (6) Cost-effectiveness. PEC efficiency is directly determined by the kinetics of each reaction step. The UNC SERC is addressing this challenge by taking a broad interdisciplinary approach in a highly collaborative setting, drawing on expertise across a broad range of disciplines in chemistry, physics and materials science. By taking a systematic approach toward a fundamental understanding of the mechanism of each step, we will be able to gain unique insight and optimize PEC design. Access to cutting-edge spectroscopic tools is critical to this research effort. We have built professionally-staffed facilities equipped with the state-of the-art instrumentation funded by this award. The combination of staff, facilities, and instrumentation specifically tailored for solar fuels research establishes the UNC Solar Energy Research Center Instrumentation Facility as a unique, world-class capability. This congressionally directed project funded the development of two user facilities: TASK 1: SOLAR

  3. Water Desalination Systems Powered by Solar Energy

    Science.gov (United States)

    Barseghyan, A.

    2015-12-01

    The supply of potable water from polluted rivers, lakes, unsafe wells, etc. is a problem of high priority. One of the most effective methods to obtain low cost drinking water is desalination. Advanced water treatment system powered by Solar Energy and based on electrodialysis for water desalination and purification, is suggested. Technological and economic evaluations and the benefits of the suggested system are discussed. The Advanced Water Treatment System proposed clears water not only from different salts, but also from some infections, thus decreasing the count of diseases which are caused by the usage of non-clear water. Using Solar Energy makes the system stand alone which is convenient to use in places where power supply is problem.

  4. Solar and Wind Power in Hybird Energy Systems in China

    OpenAIRE

    Ge, Qing

    2014-01-01

    In order to solve problems created by traditional energy, reducing the amount of usage of traditional energy and enlarging the range of usage of new energy, particularly some renewable energy should be developed immediately. In the recent years, China has been paying more attention to the utilization of renewable energy resources. Wind energy and solar energy are particularly popular due to lower cost and high economic effectiveness. As the development of wind energy and solar energy, scienti...

  5. Solar energy parking canopy demonstration project

    Energy Technology Data Exchange (ETDEWEB)

    Cylwik, Joe [City of Big Bear Lake, Big Bear, CA (United States); David, Lawrence [City of Big Bear Lake, Big Bear, CA (United States)

    2015-09-24

    The goal of this pilot/demonstration program is to measure the viability of using solar photovoltaic (PV) technology at three locations in a mountain community environment given the harsh weather conditions. An additional goal is to reduce long-term operational costs, minimize green house gas emissions, lower the dependency on energy produced from fossil fuels, and improve the working environment and health of city employees and residents.

  6. Switchable window modeling. Task 12: Building energy analysis and design tools for solar applications, Subtask A.1: High-performance glazing

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, S.; Selkowitz, S.; Winkelmann, F.

    1992-06-30

    This document presents the work conducted as part of Subtask A.1, High-Performance Glazing, of Task 12 of the IEA Solar Heating and Cooling Program. At the start of the task, the participants agreed that chromogenic technology (switchable glazing) held considerable promise, and that algorithms to accurately model their dynamic behavior were needed. The purpose of this subtask was to develop algorithms that could be incorporated into building energy analysis programs for predicting the thermal and optical performance of switchable windows. The work entailed a review of current techniques for modelling switchable glazing in windows and switchable windows in buildings and methods for improving upon existing modeling approaches. The proposed approaches correct some of the shortcomings in the existing techniques, and could be adapted for use in other similar programs. The proposed approaches generally provide more detailed calculations needed for evaluating the short-term (hourly and daily) impact of switchable windows on the energy and daylighting performance of a building. Examples of the proposed algorithms are included.

  7. Solar/electric heating systems for the future energy system

    Energy Technology Data Exchange (ETDEWEB)

    Furbo, S.; Dannemand, M.; Perers, B. [and others

    2013-05-15

    cost by 50% of the remaining auxiliary use (COP = 2) but the investment cost for the system will increase significantly. Systems based on electric heating elements are most suitable for houses with a low heat demand, while systems based on a heat pump are most attractive for houses with a high heat demand. The socio economic benefit for the national energy system is in the range 2175-6057 DKK per year for a system. A non adaptive control system based on weather forecasts, prognoses for electricity prices and simple prognoses for solar heat production of solar collectors and heat demand for a house has been tested in real life in a laboratory test facility for three different solar heating system designs: Two systems were based on electric heating elements and one system was based a heat pump. More advanced adaptive models for control based on forecasts have been developed by DTU Informatics. Solar contribution from collectors, heat demand of a house and electricity price and weather is treated to improve the efficiency and comfort of this concept in a real system with as little input as possible. Also double check of the forecast results is built in. It is expected that such an advanced control system will further decrease the energy costs somewhat for the consumer. (LN)

  8. Review of feasible solar energy applications to water processes

    Energy Technology Data Exchange (ETDEWEB)

    Blanco, J.; Malato, S.; Fernandez-Ibanez, P.; Alarcon, D.; Gernjak, W.; Maldonado, M.I. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas-Plataforma Solar de Almeria (CIEMAT-PSA), Tabernas (Almeria) (Spain)

    2009-08-15

    In the context of an upcoming energy crisis due to the decline of the Oil Era, water problems are expected to substantially worsen. And vice versa, due to the close relationship between water and energy issues, water problems are also expected to contribute to increased energy problems. Furthermore, environmental considerations, such as global warming, will surely add significant pressure. In this scenario, renewable energies are rapidly increasing their contribution to the global mix, with solar energy clearly having the greatest potential, and in view of the worldwide coincidence that where there is water stress and/or scarcity, there are also good solar radiation levels, the conclusion seems clear suitable technologies must be developed to permit the use of solar energy to simultaneously help solve energy and water problems. The main solar energy applications for water processes presented in this paper are: (1) solar desalination; (2) solar detoxification and; (3) solar disinfection. (author)

  9. Easy Solar Photovoltaic Panel as Renewable Energy System Device

    Directory of Open Access Journals (Sweden)

    Kalaivani D/O Ramachandran

    2016-04-01

    Full Text Available Solar power is energy from the sun that is converted into electrical energy. Solar energy is the abundant renewable energy source available, and the Malaysia has some of the richest solar resources in the world. Electric energy is becoming one of the source energy which is required daily. However, electric power outages always happened. Easy Solar Photovoltaic Panel as Renewable Energy System Device isimplemented as an electric power source by using solar as a help and support. It is used by providing charge through solar panel from sunlight. Then, the charge is flowing through the solar controller to charges battery that will flow to the load. Since energy that obtained from the battery are shaped in direct current (DC, then the inverter used to change direct current (DC to alternating current (AC for purpose of using device or application that using alternating current (AC to operate.

  10. Online National Solar Energy Directory and 2005 Solar Decathlon Product Directory. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Hamm, Julia; Taylor, Mike

    2008-12-31

    The Solar Electric Power Association (SEPA), in partnership with the American Solar Energy Society, developed an online National Solar Energy Directory with clear, comprehensive information on suppliers and purchasing options. The site was originally located at FindSolar.com, but has recently been moved to Find-Solar.org. The original FindSolar.com domain name has been taken by the American Solar Energy Society (a partner in this project) and utilized for a similar but different project. This Find-Solar.org directory offers the rapidly growing base of potential solar customers a simple, straightforward destination to learn about their solar options. Members of the public are able to easily locate contractors in their geographic area and verify companies' qualifications with accurate third-party information. It allows consumers to obtain key information on the economics, incentives, desirability, and workings of a solar energy system, as well as competing quotes from different contractors and reviews from customers they have worked with previously. Find-Solar.org is a means of facilitating the growing public interest in solar power and overcoming a major barrier to widespread development of U.S. solar markets. In addition to the development of Find-Solar.org, SEPA developed a separate online product directory for the 2005 DOE Solar Decathlon to facilitate the communication of information about the energy efficiency and renewable energy products used in each university team's home.

  11. Solar Energy Systems for Lunar Oxygen Generation

    Science.gov (United States)

    Colozza, Anthony J.; Heller, Richard S.; Wong, Wayne A.; Hepp, Aloysius F.

    2010-01-01

    An evaluation of several solar concentrator-based systems for producing oxygen from lunar regolith was performed. The systems utilize a solar concentrator mirror to provide thermal energy for the oxygen production process. Thermal energy to power a Stirling heat engine and photovoltaics are compared for the production of electricity. The electricity produced is utilized to operate the equipment needed in the oxygen production process. The initial oxygen production method utilized in the analysis is hydrogen reduction of ilmenite. Utilizing this method of oxygen production a baseline system design was produced. This baseline system had an oxygen production rate of 0.6 kg/hr with a concentrator mirror size of 5 m. Variations were performed on the baseline design to show how changes in the system size and process (rate) affected the oxygen production rate. An evaluation of the power requirements for a carbothermal lunar regolith reduction reactor has also been conducted. The reactor had a total power requirement between 8,320 to 9,961 W when producing 1000 kg/year of oxygen. The solar concentrator used to provide the thermal power (over 82 percent of the total energy requirement) would have a diameter of less than 4 m.

  12. Combined Solar and Wind Energy Systems

    Science.gov (United States)

    Tripanagnostopoulos, Y.; Souliotis, M.; Makris, Th.

    2010-01-01

    In this paper we present the new concept of combined solar and wind energy systems for buildings applications. Photovoltaics (PV) and small wind turbines (WTs) can be install on buildings, in case of sufficient wind potential, providing the building with electricity. PVs can be combined with thermal collectors to form the hybrid photovoltaic/thermal (PV/T) systems. The PVs (or the PV/Ts) and WT subsystems can supplement each other to cover building electrical load. In case of using PV/T collectors, the surplus of electricity, if not used or stored in batteries, can increase the temperature of the thermal storage tank of the solar thermal unit. The description of the experimental set-up of the suggested PV/T/WT system and experimental results are presented. In PV/T/WT systems the output from the solar part depends on the sunshine time and the output of the wind turbine part depends on the wind speed and is obtained any time of day or night. The use of the three subsystems can cover a great part of building energy load, contributing to conventional energy saving and environment protection. The PV/T/WT systems are considered suitable in rural and remote areas with electricity supply from stand-alone units or mini-grid connection. PV/T/WT systems can also be used in typical grid connected applications.

  13. GPP Webinar: The Solar Roadmap—Navigating the Evolving Solar Energy Market

    Science.gov (United States)

    GPP and State & Local Climate and Energy Branch webinar on the Solar Roadmap and the evolving solar energy market. This webinar discussed local and state government’s success stories and opportunities for progress in renewable energy goals using the Solar

  14. Renewable energy integration into the Australian National Electricity Market: Characterising the energy value of wind and solar generation

    OpenAIRE

    Nicholas Boerema; Merlinde Kay; Iain MacGill

    2010-01-01

    This paper examines how key characteristics of the underlying wind and solar resources may impact on their energy value within the Australian National Electricity Market(NEM). Analysis has been performed for wind generation using half hour NEM data for South Australia over the 2008-9 financial year. The potential integration of large scale solar generation has been modelled using direct normal solar radiant energy measurements from the Bureau of Meteorology for six sites across the NEM. For w...

  15. Predictive Factors Associated with Solar Energy Development in Laikipia District Central Kenya

    Directory of Open Access Journals (Sweden)

    Oscar Wambuguh

    2015-10-01

    Full Text Available The abundance of sunlight and the availability affordable solar technologies in many areas far from grid-based electricity has sparked the development of renewable energy technologies (RETs which tap solar radiation energy to provide electricity. A study on solar photovoltaics (SPVs use and utilization took place in the Wiyumiririe Location of Kenya. A purposive randomized convenience sample of 246 households was selected and landowner interviews conducted guided by a questionnaire, followed by field surveys and observations. Although solar energy contributed less than a quarter of total household energy needs, residents specifically associated it with specific developmental initiatives. Correlation and logistic regression model analyses showed that solar power development was closely associated (and thus can be predicted from five main independent variables. The findings of the study allowed the development of a probabilistic model general enough to be applicable elsewhere in the development of alternative energy resources particularly those based on solar input.

  16. Energy savings for solar heating systems; Solvarmeanlaegs energibesparelser

    Energy Technology Data Exchange (ETDEWEB)

    Furbo, S.; Fan, J.

    2011-01-15

    Energy savings for a number of new solar heating systems in one family houses have been determined by means of information on the energy consumption of the houses before and after installation of the solar heating systems. The investigated solar heating systems are marketed by Velux Danmark A/S, Sonnnenkraft Scandinavia A/S and Batec Solvarme A/S. Solar domestic hot water systems as well as solar combi systems are included in the investigations The houses have different auxiliary energy supply systems: Natural gas boilers, oil fired burners, electrical heating and district heating. Some of the houses have a second auxiliary energy supply system. The collector areas vary from 1.83 m{sup 2} to 9.28 m{sup 2}. Some of the solar heating systems are based on energy units with a new integrated natural gas boiler and a heat storage for the solar heating system. The existing energy systems in the houses are for most of the houses used as the auxiliary energy systems for the solar heating systems. The yearly energy savings for the houses where the only change is the installation of the solar heating system vary from 300 kWh per m{sup 2} solar collector to 1300 kWh per m{sup 2} solar collector. The average yearly energy savings is about 670 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector are not influenced by the solar heating system type, the company marketing the system, the auxiliary energy supply system, the collector area, the collector tilt, the collector azimuth, the energy consumption of the house or the location of the house. The yearly energy savings for the houses with solar heating systems based on energy units including a new natural gas boiler vary from 790 kWh per m{sup 2} solar collector to 2090 kWh per m{sup 2} solar collector. The average yearly energy savings is about 1520 kWh per m{sup 2} solar collector for these solar heating systems. The energy savings per m{sup 2} solar collector for

  17. Helioseismology challenges models of solar convection

    CERN Document Server

    Gizon, Laurent; 10.1073/pnas.1208875109

    2012-01-01

    Convection is the mechanism by which energy is transported through the outermost 30% of the Sun. Solar turbulent convection is notoriously difficult to model across the entire convection zone where the density spans many orders of magnitude. In this issue of PNAS, Hanasoge et al. (2012) employ recent helioseismic observations to derive stringent empirical constraints on the amplitude of large-scale convective velocities in the solar interior. They report an upper limit that is far smaller than predicted by a popular hydrodynamic numerical simulation.

  18. Electrochemical nano-coating processes in solar energy systems

    Directory of Open Access Journals (Sweden)

    F. Kadırgan

    2006-01-01

    Full Text Available The efficiencies of electrochemically prepared nano-thick CdS and black nickel coatings were investigated as a function of their preparation conditions in the application field of energy; such as, solar-electricity conversion, solar cells, and solar-thermal conversion, spectrally selective solar collectors.

  19. Modeling the impact of forest biomass change on the subsequent ground level solar energy to enhance the understanding of ecosystem service tradeoffs

    Science.gov (United States)

    Background/Question/Methods Solar radiation is a significant environmental driver that impacts the quality and resilience of terrestrial and aquatic habitats, yet its spatiotemporal variations are complicated to model accurately at high resolution over large, complex watersheds. ...

  20. Solar models: An historical overview

    Energy Technology Data Exchange (ETDEWEB)

    Bahcall, John N. E-mail: jnb@ias.edu

    2003-04-01

    I will summarize in four slides the 40 years of development of the standard solar model that is used to predict solar neutrino fluxes and then describe the current uncertainties in the predictions. I will dispel the misconception that the p-p neutrino flux is determined by the solar luminosity and present a related formula that gives, in terms of the p-p and {sup 7}Be neutrino fluxes, the ratio of the rates of the two primary ways of terminating the p-p fusion chain. I will also attempt to explain why it took so long, about three and a half decades, to reach a consensus view that new physics is being learned from solar neutrino experiments. Finally, I close with a personal confession.

  1. Solar Models An Historical Overview

    CERN Document Server

    Bahcall, J N

    2002-01-01

    I summarize in four slides the 40 years of development of the standard solar model that is used to predict solar neutrino fluxes and then describe the current uncertainties in the predictions. I next dispel the misconception that the p-p neutrino flux is determined by the solar luminosity and present a related formula that gives, in terms of the p-p and 7Be neutrino fluxes, the ratio of the rates of the two primary ways of terminating the p-p fusion chain. I will also attempt to explain why it took so long, about three and a half decades, to reach a consensus view that new physics is being learned from solar neutrino experiments. Finally, I close with a personal confession.

  2. Deterministically Driven Avalanche Models of Solar Flares

    Science.gov (United States)

    Strugarek, Antoine; Charbonneau, Paul; Joseph, Richard; Pirot, Dorian

    2014-08-01

    We develop and discuss the properties of a new class of lattice-based avalanche models of solar flares. These models are readily amenable to a relatively unambiguous physical interpretation in terms of slow twisting of a coronal loop. They share similarities with other avalanche models, such as the classical stick-slip self-organized critical model of earthquakes, in that they are driven globally by a fully deterministic energy-loading process. The model design leads to a systematic deficit of small-scale avalanches. In some portions of model space, mid-size and large avalanching behavior is scale-free, being characterized by event size distributions that have the form of power-laws with index values, which, in some parameter regimes, compare favorably to those inferred from solar EUV and X-ray flare data. For models using conservative or near-conservative redistribution rules, a population of large, quasiperiodic avalanches can also appear. Although without direct counterparts in the observational global statistics of flare energy release, this latter behavior may be relevant to recurrent flaring in individual coronal loops. This class of models could provide a basis for the prediction of large solar flares.

  3. Commercial applications of solar total energy systems. Volume 4. Appendices. Final report. [Solar Total Energy System Evaluation Program (STESEP) code

    Energy Technology Data Exchange (ETDEWEB)

    Boobar, M.G.; McFarland, B.L.; Nalbandian, S.J.; Willcox, W.W.; French, E.P.; Smith, K.E.

    1978-07-01

    A methodology has been developed by Atomics International under contract to the Department of Energy to define the applicability of solar total energy systems (STES) to the commercial sector (e.g., retail stores, shopping centers, offices, etc.) in the United States. Candidate STES concepts were selected to provide on-site power generation capability, as well as thermal energy for both heating and cooling applications. Each concept was evaluated on the basis of its cost effectiveness (i.e., as compared to other concepts) and its ability to ultimately penetrate and capture a significant segment of this market, thereby resulting in a saving of fossil fuel resources. This volume contains the appendices. Topics include deterministic insolation model computer code; building energy usage data; computer simulation programs for building energy demand analysis; model buildings for STES evaluation; Solar Total Energy System Evaluation Program (STESEP) computer code; transient simulation of STES concept; solar data tape analysis; program listings and sample output for use with TRNSYS; transient simulation, and financial parameters sensitivities. (WHK)

  4. Optimal Electron Energies for Driving Chromospheric Evaporation in Solar Flares

    CERN Document Server

    Reep, Jeffrey; Alexander, David

    2015-01-01

    In the standard model of solar flares, energy deposition by a beam of electrons drives strong chromospheric evaporation leading to a significantly denser corona and much brighter emission across the spectrum. Chromospheric evaporation was examined in great detail by Fisher, Canfield, & McClymont (1985a,b,c), who described a distinction between two different regimes, termed explosive and gentle evaporation. In this work, we examine the importance of electron energy and stopping depths on the two regimes and on the atmospheric response. We find that with explosive evaporation, the atmospheric response does not depend strongly on electron energy. In the case of gentle evaporation, lower energy electrons are significantly more efficient at heating the atmosphere and driving up-flows sooner than higher energy electrons. We also find that the threshold between explosive and gentle evaporation is not fixed at a given beam energy flux, but also depends strongly on the electron energy and duration of heating. Furt...

  5. Community Solar Program Final Report for Austin Energy

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2013-02-10

    Austin Energy seeks to expand its portfolio of renewable programs with an innovative community solar program. The program provides an opportunity for Austin Energy's customers, who are unable or uninterested in installing solar on their own premises, to purchase solar power.

  6. U.S. Department of Energy Workshop Report: Solar Resources and Forecasting

    Energy Technology Data Exchange (ETDEWEB)

    Stoffel, T.

    2012-06-01

    This report summarizes the technical presentations, outlines the core research recommendations, and augments the information of the Solar Resources and Forecasting Workshop held June 20-22, 2011, in Golden, Colorado. The workshop brought together notable specialists in atmospheric science, solar resource assessment, solar energy conversion, and various stakeholders from industry and academia to review recent developments and provide input for planning future research in solar resource characterization, including measurement, modeling, and forecasting.

  7. Computational Analysis of Energy Pooling to Harvest Low-Energy Solar Energy in Organic Photovoltaic Devices

    Science.gov (United States)

    Lacount, Michael; Shaheen, Sean; Rumbles, Garry; van de Lagemaat, Jao; Hu, Nan; Ostrowski, Dave; Lusk, Mark

    2014-03-01

    Current photovoltaic energy conversions do not typically utilize low energy sunlight absorption, leaving large sections of the solar spectrum untapped. It is possible, though, to absorb such radiation, generating low-energy excitons, and then pool them to create higher energy excitons, which can result in an increase in efficiency. Calculation of the rates at which such upconversion processes occur requires an accounting of all possible molecular quantum electrodynamics (QED) pathways. There are two paths associated with the upconversion. The cooperative mechanism involves a three-body interaction in which low energy excitons are transferred sequentially onto an acceptor molecule. The accretive pathway, requires that an exciton transfer its energy to a second exciton that subsequently transfers its energy to the acceptor molecule. We have computationally modeled both types of molecular QED obtaining rates using a combination of DFT and many-body Green function theory. The simulation platform is exercised by considering upconversion events associated with material composed of a high energy absorbing core of hexabenzocoronene (HBC) and low energy absorbing arms of oligothiophene. In addition, we make estimates for all competing processes in order to judge the relative efficiencies of these two processes.

  8. Climate studies with a multi-layer energy balance model. I - Model description and sensitivity to the solar constant. II - The role of feedback mechanisms in the CO2 problem

    Science.gov (United States)

    Peng, L.; Chou, M.-D.; Arking, A.

    1982-01-01

    A nine-layer zonally averaged, steady-state model, based upon thermal energy balance, is developed for use in climate sensitivity studies and includes an accurate treatment of radiative transfer, parameterized meridional and vertical energy transport, and thermodynamic interaction between the surface and the atmosphere. A high degree of nonlinearity is exhibited by the model in a study of sensitivity to changes in the solar constant. The change in the hemispheric mean surface temperature is +3.1 C in response to a 2% increase in the solar constant and -4.3 C in response to a 2% decrease in the solar constant. The sensitivity varies with latitude, and the response of atmospheric temperature varies with height. In addition, the model is used to study the sensitivity of climate to a doubling of the atmospheric CO2 content. It is found that the tropospheric temperature lapse rate decreases at low latitudes but increases at high latitudes in response to a doubled CO2 content. Averaged over the Northern Hemisphere, the change is +2.3 C in the surface temperature and +0.47 C in the earth's brightness temperature. The effects of some feedback mechanisms on the climate sensitivity to a doubled CO2 content show that the sensitivity of surface temperature approximately doubles at all latitudes due to the change in water vapor content.

  9. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.; Hagstroem, M.; Lund, P. [Helsinki Univ. of Technology, Otaniemi (Finland). Advanced Energy Systems

    1998-10-01

    The main technical constraint in solar energy systems which operate around the year is the lack of suitable long-term energy storage. Conventional solutions to overcome the problem of seasonal storage in PV power systems are to use oversized batteries as a seasonal energy storage, or to use a diesel back-up generator. However, affordable lead-acid batteries are not very suitable for seasonal energy storage because of a high self-discharge rate and enhanced deterioration and divergence of the single cells during prolonged periods of low state of charge in times of low irradiation. These disadvantages can be avoided by a back-up system, e.g. a diesel generator, which car supply energy to the loads and charge the battery to the full state of charge to avoid the above mentioned disadvantages. Unfortunately, diesel generators have several disadvantages, e.g. poor starting reliability, frequent need for maintenance and noise

  10. Wind and solar energy in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Nasir, S.M.; Raza, S.M. (Balochistan Univ., Quetta (Pakistan). Dept. of Physics)

    1993-04-01

    Hourly wind-speed data at four meteorological observatories (Quetta, Karachi, Peshawar, and Lahore) in Pakistan have been analysed to determine monthly and annual wind power and these are then compared with the monthly mean solar radiation energies for the period 1980-1984. The monthly average wind speeds for the four stations range from 2.5 to 4.4, 2.75 to 6.7, 0.6 to 1.7, and 0.7 to 1.6 m/sec while the solar radiation varies from 3.6 to 7.65, 3.39 to 6.31, 2.4 to 6.35, and 2.8 to 6.27 kWh/m[sup 2], respectively. (author)

  11. Calculating the Solar Energy of a Flat Plate Collector

    Directory of Open Access Journals (Sweden)

    Ariane Rosario

    2014-09-01

    Full Text Available The amount of solar energy that could be obtained by a flat plate solar collector of one square meter dimension is calculated in three different locations: Tampa FL, Fairbanks AL, and Pontianak Indonesia, considering the varying sunset time for each day of the year. The results show that if the collectors are placed near the equator, more total energy could be obtained. In fact, by placing a solar collector in Pontianak, Indonesia 12.42% more solar energy can be obtained than by placing it in Tampa and 96.9% more solar energy than Alaska.

  12. DESIGN AND IMPLEMENTATION OF A SOLAR ENERGY EDUCATIONAL SET

    Directory of Open Access Journals (Sweden)

    İbrahim SEFA

    2007-03-01

    Full Text Available In this study, an educational tool which can be used to obtain electrical energy from solar energy has been designed and implemented. The obtained energy can be used both for direct current and alternating current. Moreover, the energy can be charged into an accumulator group on request. Several experiments related to obtaining electrical energy from solar energy, storing the energy and conversion systems are prepared on the developed educational set. The educational set presented in this paper can be used as an educational tool for increasing knowledge, skill and abilities of students about the converting solar energy to the electrical energy.

  13. The influence of the solar radiation model on the calcutated solar radiation from a horizontal surface to a tilted surface

    DEFF Research Database (Denmark)

    Andersen, Elsa; Lund, Hans; Furbo, Simon

    2004-01-01

    in the calculation. The weather data are measured at the solar radiation measurement station, SMS at the Department of Civil Engineering at the Technical University of Denmark. In this study the weather data are combined with solar collector calculations based on solar collector test carried out at Solar Energy......Measured solar radiation data are most commonly available as total solar radiation on a horizontal surface. When using solar radiation measured on horizontal to calculate the solar radiation on tilted surfaces and thereby the thermal performance of different applications such as buildings and solar...... heating systems, different solar radiation models can be used. The calculation of beam radiation from a horizontal surface to a tilted surface can be done exactly whereas different solar radiation models can calculate the sky diffuse radiation. The sky diffuse radiation can either be assumed evenly...

  14. Next generation solar energy. From fundamentals to applications

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    Within the International Conference between 12th and 14th December, 2011 in Erlangen (Federal Republic of Germany) the following lectures were presented: (1) The opto-electronic physics required to approach the Shockley-Queisser efficiency limit (E. Yablonovitch); (2) The Shockley-Queisser-limit and beyond (G.H. Bauer); (3) Designing composite nanomaterials for photovoltaic devices (B. Rech); (4) Light-Material interactions in energy conversion (H. Atwater); (5) Functional imaging of hybrid nanostructures - Visualizing mechanisms of solar energy utilization (L. Lauhon); (6) Are photosynthetic proteins suitable for PV applications (Y. Rosenwaks); (7) Detailed balance limit in photovoltaic systems (U. Rau); (8) Plasmonics and nanophotonics for next generation photovoltaics (E. Garnett); (9) Dispersion, wave propagation and efficiency analysis of nanowire solar cells (B. Witzigmann); (10) Application of nanostructures to next generation photovoltaics - Opportunities and challenges from an industrial research perspective (L. Tsakalakos); (11) Triplet states in organic and organometallic photovoltaic cells (K.S. Schanze); (12) New photoelectrode architectures (J.T. Hupp); (13) Dendrimers for optoelectronic and photovoltaic applications (P. Ceroni); (14) Photon management with luminescent materials (J. Goldschmidt); (15) Economical aspects of next generation solar cell technologies (W. Hoffmann); (16) Scalability in solar energy conversion - First-row transition metal-based chromophores for dye-sensitized solar cells (J. McCusker); (17) Designing organic materials for photovoltaic devices (A. Harriman); (18) Molecular photovoltaics - What can we learn from model studies (B. Albinsson); (19) Porphyrin-sensitised titanium dioxide solar cells (D. Officer); (20) Light-harvesting: Charge separation, and charge-transportation properties of novel materials for organic photovoltaics (H. Imahori); (21) Phthalocyanines for molecular photovoltaics (T. Torres); (22) Photophysics of

  15. A Systematic Evaluation Model for Solar Cell Technologies

    Directory of Open Access Journals (Sweden)

    Chang-Fu Hsu

    2014-01-01

    Full Text Available Fossil fuels, including coal, petroleum, natural gas, and nuclear energy, are the primary electricity sources currently. However, with depletion of fossil fuels, global warming, nuclear crisis, and increasing environmental consciousness, the demand for renewable energy resources has skyrocketed. Solar energy is one of the most popular renewable energy resources for meeting global energy demands. Even though there are abundant studies on various solar technology developments, there is a lack of studies on solar technology evaluation and selection. Therefore, this research develops a model using interpretive structural modeling (ISM, benefits, opportunities, costs, and risks concept (BOCR, and fuzzy analytic network process (FANP to aggregate experts' opinions in evaluating current available solar cell technology. A case study in a photovoltaics (PV firm is used to examine the practicality of the proposed model in selecting the most suitable technology for the firm in manufacturing new products.

  16. Solar/Electromagnetic Energy Harvesting and Wireless Power Transmission

    OpenAIRE

    2014-01-01

    This paper presents a review of existing works and solutions in the field of solar/electromagnetic energy harvesting and wireless power transmission. More specifically, the paper covers: solar/electromagnetic harvesters where solar antenna structures are used to obtain a compact implementation, direct current (dc) combining circuits necessary to combine the outputs of the solar and the electromagnetic harvesters, and efficient solar-to-electromagnetic (EM) converters that can be used to synth...

  17. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

    1998-12-31

    Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

  18. Evaluation of the solar energy potential in Piracicaba, Sao Paulo State, Brazil; Avaliacao do potencial de energia solar no municipio de Piracicaba, SP, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Villa Nova, Nilson Augusto [Sao Paulo Univ., Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz. Dept. de Fisica e Meterorologia; Pereira, Andre Belmont [Universidade Estadual de Ponta Grossa, PR (Brazil). Dept. de Ciencia do Solo e Engenharia Agricola

    1997-07-01

    This paper presents a development of a mathematical model for evaluation of the solar energy potential available in Piracicaba, SP, Brazil, as function of only a radiometric measurement in the zenital passage. Solar energy potential values determined by the proposed methodology will allow the evaluation of the maximum possible performance of the energy capture systems. These potential values will be very important in engineering projects which have the objective of solar energy utilization in its various forms.

  19. Diffusion of solar energy technologies in the new-construction market: a survey of new solar-home and onventional-home buyers

    Energy Technology Data Exchange (ETDEWEB)

    Rains, D.; Dunipace, D.; Woo, C.K.

    1981-02-01

    Comsumer motivations for choosing a solar energy equipped new home when the non-solar or conventional model was also available were investigated. The approach was to test the relative importance of demographic, dwelling unit, and heating system characteristics in household decisions to purchase a home equipped with solar energy devices. Two statistical models were developed: one to examine the relationship between the types of home buyers (as an identifiable market segment) and the decision to purchase a solar home, and the other to compare the energy use of solar vs. conventional homes selected in the sample. (MHR)

  20. Solar energy in California industry - Applications, characteristics and potential

    Science.gov (United States)

    Barbieri, R. H.; Pivirotto, D. S.

    1978-01-01

    Results of a survey to determine the potential applicability of solar thermal energy to industrial processes in California are presented. It is found that if the heat for all industrial processes at temperatures below 212 F were supplied by solar energy, total state energy consumption could be reduced by 100 trillion Btus (2%), while the use of solar energy in processes between 212 and 350 F could displace 500 trillion Btus. The issues and problems with which solar energy must contend are illustrated by a description of fluid milk processing operations. Solar energy application is found to be technically feasible for processes with thermal energy requirements below 212 F, with design, and degree of technical, economic and management feasibility being site specific. It is recommended that the state provide support for federal and industrial research, development and demonstration programs in order to stimulate acceptance of solar process heat application by industry.

  1. Solar energy in California industry - Applications, characteristics and potential

    Science.gov (United States)

    Barbieri, R. H.; Pivirotto, D. S.

    1978-01-01

    Results of a survey to determine the potential applicability of solar thermal energy to industrial processes in California are presented. It is found that if the heat for all industrial processes at temperatures below 212 F were supplied by solar energy, total state energy consumption could be reduced by 100 trillion Btus (2%), while the use of solar energy in processes between 212 and 350 F could displace 500 trillion Btus. The issues and problems with which solar energy must contend are illustrated by a description of fluid milk processing operations. Solar energy application is found to be technically feasible for processes with thermal energy requirements below 212 F, with design, and degree of technical, economic and management feasibility being site specific. It is recommended that the state provide support for federal and industrial research, development and demonstration programs in order to stimulate acceptance of solar process heat application by industry.

  2. Assessment of solar energy programmes in Bhutan

    Energy Technology Data Exchange (ETDEWEB)

    Parthan, B.; Monga, P. [UNIDO, Vienna (Austria); Giri, S. [UNDP, United Nation Building, Thimphu (Bhutan); Adhikari, R.N. [Norlha Associates, Thimphu (Bhutan)

    2004-07-01

    The paper reports on the renewable energy and solar electrification programmes in Bhutan. Findings from a field survey of PV systems have been presented and lessons identified. A discussion of the key results from the assessments are also presented and conclusions drawn. The paper provides direct feedback on the performance of PV systems in difficult geographical conditions such as those prevailing in Bhutan. The results and findings of this paper are relevant to PV industry targeting rural electrification markets and policy makers and aid-planners involved in PV rural electrification initiatives. (authors)

  3. Defect Tolerant Semiconductors for Solar Energy Conversion.

    Science.gov (United States)

    Zakutayev, Andriy; Caskey, Christopher M; Fioretti, Angela N; Ginley, David S; Vidal, Julien; Stevanovic, Vladan; Tea, Eric; Lany, Stephan

    2014-04-03

    Defect tolerance is the tendency of a semiconductor to keep its properties despite the presence of crystallographic defects. Scientific understanding of the origin of defect tolerance is currently missing. Here we show that semiconductors with antibonding states at the top of the valence band are likely to be tolerant to defects. Theoretical calculations demonstrate that Cu3N with antibonding valence band maximum has shallow intrinsic defects and no surface states, in contrast to GaN with bonding valence band maximum. Experimental measurements indicate shallow native donors and acceptors in Cu3N thin films, leading to 10(16)-10(17) cm(-3) doping with either electrons or holes depending on the growth conditions. The experimentally measured bipolar doping and the solar-matched optical absorption onset (1.4 eV) make Cu3N a promising candidate absorber for photovoltaic and photoelectrochemical solar cells, despite the calculated indirect fundamental band gap (1.0 eV). These conclusions can be extended to other materials with antibonding character of the valence band, defining a class of defect-tolerant semiconductors for solar energy conversion applications.

  4. Residual Energy Spectrum of Solar Wind Turbulence

    CERN Document Server

    Chen, C H K; Salem, C S; Maruca, B A

    2013-01-01

    It has long been known that the energy in velocity and magnetic field fluctuations in the solar wind is not in equipartition. In this paper, we present an analysis of 5 years of Wind data at 1 AU to investigate the reason for this. The residual energy (difference between energy in velocity and magnetic field fluctuations) was calculated using both the standard magnetohydrodynamic (MHD) normalization for the magnetic field and a kinetic version, which includes temperature anisotropies and drifts between particle species. It was found that with the kinetic normalization, the fluctuations are closer to equipartition, with a mean normalized residual energy of sigma_r = -0.19 and mean Alfven ratio of r_A = 0.71. The spectrum of residual energy, in the kinetic normalization, was found to be steeper than both the velocity and magnetic field spectra, consistent with some recent MHD turbulence predictions and numerical simulations, having a spectral index close to -1.9. The local properties of residual energy and cros...

  5. Solar energy contribution to the energy demand for air conditioning system in an office building under Tripoli climate conditions

    Directory of Open Access Journals (Sweden)

    Musbah Mohamed H.

    2014-01-01

    Full Text Available The feasibility of solar assisted air conditioning in an office building under Tripoli weather conditions is investigated in this paper. A single-effect lithium bromide absorption cycle powered by means of flat-plate solar collectors was modeled in order to predict the potential of the solar energy share. The cooling load profile was generated by using an detailed hourly based program and Typical meteorological year for Tripoli. System performance and solar energy fraction were calculated by varying two major parameters (collector’s slope angle and collector area. The maximum solar fraction of 48% was obtained by means of 1400 m2 of collector surface area. Analysis of results showed that, besides the collector surface area, the main factors affecting the solar fraction were the local weather conditions (intensity of incident solar radiation and the time of day when the plant was operated.

  6. Alive and well: a short review about standard solar models

    CERN Document Server

    Serenelli, Aldo

    2016-01-01

    Standard solar models (SSMs) provide a reference framework across a number of research fields: solar and stellar models, solar neutrinos, particle physics the most conspicuous among them. The accuracy of the physical description of the global properties of the Sun that SSMs provide has been challenged in the last decade by a number of developments in stellar spectroscopic techniques. Over the same period of time, solar neutrino experiments, and Borexino in particular, have measured the four solar neutrino fluxes from the pp-chains that are associated with 99\\% of the nuclear energy generated in the Sun. Borexino has also set the most stringent limit on CNO energy generation, only $\\sim 40\\%$ larger than predicted by SSMs. More recently, and for the first time, radiative opacity experiments have been performed at conditions that closely resemble those at the base of the solar convective envelope. In this article, we review these developments and discuss the current status of SSMs, including its intrinsic limit...

  7. Alive and well: A short review about standard solar models

    Energy Technology Data Exchange (ETDEWEB)

    Serenelli, Aldo [Campus UAB, Carrer de Can Magrans S/N, Instituto de Ciencias del Espacio (ICE/CSIC-IEEC), Cerdanyola del Valles (Spain)

    2016-04-15

    Standard solar models (SSMs) provide a reference framework across a number of research fields: solar and stellar models, solar neutrinos, particle physics the most conspicuous among them. The accuracy of the physical description of the global properties of the Sun that SSMs provide has been challenged in the last decade by a number of developments in stellar spectroscopic techniques. Over the same period of time, solar neutrino experiments, and Borexino in particular, have measured the four solar neutrino fluxes from the pp-chains that are associated with 99% of the nuclear energy generated in the Sun. Borexino has also set the most stringent limit on CNO energy generation, only ∝ 40% larger than predicted by SSMs. More recently, and for the first time, radiative opacity experiments have been performed at conditions that closely resemble those at the base of the solar convective envelope. In this article, we review these developments and discuss the current status of SSMs, including its intrinsic limitations. (orig.)

  8. Organohalide Perovskites for Solar Energy Conversion.

    Science.gov (United States)

    Lin, Qianqian; Armin, Ardalan; Burn, Paul L; Meredith, Paul

    2016-03-15

    Lead-based organohalide perovskites have recently emerged as arguably the most promising of all next generation thin film solar cell technologies. Power conversion efficiencies have reached 20% in less than 5 years, and their application to other optoelectronic device platforms such as photodetectors and light emitting diodes is being increasingly reported. Organohalide perovskites can be solution processed or evaporated at low temperatures to form simple thin film photojunctions, thus delivering the potential for the holy grail of high efficiency, low embedded energy, and low cost photovoltaics. The initial device-driven "perovskite fever" has more recently given way to efforts to better understand how these materials work in solar cells, and deeper elucidation of their structure-property relationships. In this Account, we focus on this element of organohalide perovskite chemistry and physics in particular examining critical electro-optical, morphological, and architectural phenomena. We first examine basic crystal and chemical structure, and how this impacts important solar-cell related properties such as the optical gap. We then turn to deeper electronic phenomena such as carrier mobilities, trap densities, and recombination dynamics, as well as examining ionic and dielectric properties and how these two types of physics impact each other. The issue of whether organohalide perovskites are predominantly nonexcitonic at room temperature is currently a matter of some debate, and we summarize the evidence for what appears to be the emerging field consensus: an exciton binding energy of order 10 meV. Having discussed the important basic chemistry and physics we turn to more device-related considerations including processing, morphology, architecture, thin film electro-optics and interfacial energetics. These phenomena directly impact solar cell performance parameters such as open circuit voltage, short circuit current density, internal and external quantum efficiency

  9. Global Energetics of Solar Flares. Part III; Nonthermal Energies

    Science.gov (United States)

    Aschwanden, Markus J.; Holman, Gordon; O'Flannagain, Aidan; Caspi, Amir; McTiernan, James M.; Kontar, Eduard P.

    2016-01-01

    This study entails the third part of a global flare energetics project, in which Ramaty High-Energy Solar Spectroscopic Imager (RHESSI) data of 191 M and X-class flare events from the first 3.5 years of the Solar Dynamics Observatory mission are analyzed. We fit a thermal and a nonthermal component to RHESSI spectra, yielding the temperature of the differential emission measure (DEM) tail, the nonthermal power-law slope and flux, and the thermal nonthermal cross-over energy eco. From these parameters, we calculate the total nonthermal energy E(sub nt) in electrons with two different methods: (1) using the observed cross-over energy e(sub co) as low-energy cutoff, and (2) using the low-energy cut off e(sub wt) predicted by the warm thick-target bremsstrahlung model of Kontar et al. Based on a mean temperature of T(sub e) = 8.6 MK in active regions, we find low-energy cutoff energies of e(sub wt) = 6.2 +/-1.6 keV for the warm-target model, which is significantly lower than the cross-over energies e(sub co) = 21 +/- 6 keV. Comparing with the statistics of magnetically dissipated energies E(sub mag) and thermal energies E(sub th) from the two previous studies, we find the following mean (logarithmic) energy ratios with the warm-target model: E(sub nt) = 0.41E(sub mag), E(sub th) = 0.08 E(sub mag), and E(sub th) = 0.15 E(sub nt). The total dissipated magnetic energy exceeds the thermal energy in 95% and the nonthermal energy in 71% of the flare events, which confirms that magnetic reconnection processes are sufficient to explain flare energies. The nonthermal energy exceeds the thermal energy in 85% of the events, which largely confirms the warm thick-target model.

  10. Solar Energy: Progress and Design Concerns of Nanostructured Solar Energy Harvesting Devices (Small 19/2016).

    Science.gov (United States)

    Leung, Siu-Fung; Zhang, Qianpeng; Tavakoli, Mohammad Mahdi; He, Jin; Mo, Xiaoliang; Fan, Zhiyong

    2016-05-01

    Nanoengineered materials and structures can harvest light efficiently for photovoltaic applications. Device structure design optimization and material property improvement are equally important for high performance. On page 2536, X. Mo, Z. Fan, and co-workers summarize the design guidelines of solar energy harvesting devices to assist with a better understanding of device physics.

  11. Nuclear energy + solar energy, why not?; Energia nuclear + energia solar, por que no?

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez C, I.; Nelson E, P., E-mail: ihernandezc91@hotmail.com [UNAM, Facultad de Ingenieria, Ciudad Universitaria, 04510 Ciudad de Mexico (Mexico)

    2016-09-15

    Clean energies such as nuclear and solar are part of the solution to the energy dependence that we face today and also help us to reduce the greenhouse gas emissions, thus avoiding a global average temperature increase that is irreversible and harmful to all living beings on the planet. Independently the nuclear and solar energies have had a great development in recent years, so in this work we set ourselves the task of creating a synergy between them. First, we conducted a survey of different people involved in the area of energy (energy efficiency, clean energy and renewable sources) in order to know if the area of which they are part influences with respect to the impression that they have of safety in terms of supply, return on investment and safety to the health and environment of another energy source for which we use a correlation analysis. With the results obtained we propose to use photo thermic solar energy as a support to reduce the frequency of accidents by station blackout and we perform the analysis of the combination using the methodology of Probabilistic Analysis of Security with the help of SAPHIRE 7 software to realize the event trees by station blackout of a nuclear power plant and faults for a photo-thermal solar plant. Finally, the decrease in the probability of station blackout from the proposed combination is quantified. The results were favorable to indicate that the probability of station blackout is reduced in half and that is why is suggested to continue studying the combination. (Author)

  12. Assessing Rare Metal Availability Challenges for Solar Energy Technologies

    Directory of Open Access Journals (Sweden)

    Leena Grandell

    2015-08-01

    Full Text Available Solar energy is commonly seen as a future energy source with significant potential. Ruthenium, gallium, indium and several other rare elements are common and vital components of many solar energy technologies, including dye-sensitized solar cells, CIGS cells and various artificial photosynthesis approaches. This study surveys solar energy technologies and their reliance on rare metals such as indium, gallium, and ruthenium. Several of these rare materials do not occur as primary ores, and are found as byproducts associated with primary base metal ores. This will have an impact on future production trends and the availability for various applications. In addition, the geological reserves of many vital metals are scarce and severely limit the potential of certain solar energy technologies. It is the conclusion of this study that certain solar energy concepts are unrealistic in terms of achieving TW scales.

  13. Solar microclimatology. [tables (data) on insolation for application to solar energy conversion by electric power plants

    Science.gov (United States)

    Mckenney, D. B.; Beauchamp, W. T.

    1975-01-01

    It has become apparent in recent years that solar energy can be used for electric power production by several methods. Because of the diffuse nature of the solar insolation, the area involved in any central power plant design can encompass several square miles. A detailed design of these large area collection systems will require precise knowledge of the local solar insolation. Detailed information will also be needed concerning the temporal nature of the insolation and the local spatial distribution. Therefore, insolation data was collected and analyzed for a network of sensors distributed over an area of several square kilometers in Arizona. The analyses of this data yielded probability distributions of cloud size, velocity, and direction of motion which were compared with data obtained from the National Weather Service. Microclimatological analyses were also performed for suitable modeling parameters pertinent to large scale electric power plant design. Instrumentation used to collect the data is described.

  14. Solar energy grid integration systems "SEGIS"

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2007-10-01

    The inevitable transformation of the electrical grid to a more distributed generation configuration requires solar system capabilities well beyond simple net-metered, grid-connected approaches. Time-of-use and peak-demand rate structures will require more sophisticated systems designs that integrate energy management and/or energy storage into the system architecture. Controlling power flow into and from the utility grid will be required to ensure grid reliability and power quality. Alternative protection strategies will also be required to accommodate large numbers of distributed energy sources. This document provides an overview of the R&D needs and describes some pathways to promising solutions. The solutions will, in many cases, require R&D of new components, innovative inverter/controllers, energy management systems, innovative energy storage and a suite of advanced control algorithms, technical methodologies, protocols and the associated communications. It is expected that these solutions will help to push the “advanced integrated system” and “smart grid” evolutionary processes forward in a faster but focused manner.

  15. Modelling the influence of photospheric turbulence on solar flare statistics

    Science.gov (United States)

    Mendoza, M.; Kaydul, A.; de Arcangelis, L.; Andrade, J. S., Jr.; Herrmann, H. J.

    2014-09-01

    Solar flares stem from the reconnection of twisted magnetic field lines in the solar photosphere. The energy and waiting time distributions of these events follow complex patterns that have been carefully considered in the past and that bear some resemblance with earthquakes and stockmarkets. Here we explore in detail the tangling motion of interacting flux tubes anchored in the plasma and the energy ejections resulting when they recombine. The mechanism for energy accumulation and release in the flow is reminiscent of self-organized criticality. From this model, we suggest the origin for two important and widely studied properties of solar flare statistics, including the time-energy correlations. We first propose that the scale-free energy distribution of solar flares is largely due to the twist exerted by the vorticity of the turbulent photosphere. Second, the long-range temporal and time-energy correlations appear to arise from the tube-tube interactions. The agreement with satellite measurements is encouraging.

  16. Photovoltaic and photoelectrochemical conversion of solar energy.

    Science.gov (United States)

    Grätzel, Michael

    2007-04-15

    The Sun provides approximately 100,000 terawatts to the Earth which is about 10000 times more than the present rate of the world's present energy consumption. Photovoltaic cells are being increasingly used to tap into this huge resource and will play a key role in future sustainable energy systems. So far, solid-state junction devices, usually made of silicon, crystalline or amorphous, and profiting from the experience and material availability resulting from the semiconductor industry, have dominated photovoltaic solar energy converters. These systems have by now attained a mature state serving a rapidly growing market, expected to rise to 300 GW by 2030. However, the cost of photovoltaic electricity production is still too high to be competitive with nuclear or fossil energy. Thin film photovoltaic cells made of CuInSe or CdTe are being increasingly employed along with amorphous silicon. The recently discovered cells based on mesoscopic inorganic or organic semiconductors commonly referred to as 'bulk' junctions due to their three-dimensional structure are very attractive alternatives which offer the prospect of very low cost fabrication. The prototype of this family of devices is the dye-sensitized solar cell (DSC), which accomplishes the optical absorption and the charge separation processes by the association of a sensitizer as light-absorbing material with a wide band gap semiconductor of mesoporous or nanocrystalline morphology. Research is booming also in the area of third generation photovoltaic cells where multi-junction devices and a recent breakthrough concerning multiple carrier generation in quantum dot absorbers offer promising perspectives.

  17. Evaluation of the photochemical production of hydrogen from solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Heppert, J. A.

    1977-08-09

    The potential for utilizing solar energy through photochemical storage were investigated. Both water and nitrosyl chloride systems are examined. A comprehensive review of the literature led to the conclusion that many major questions must be answered before photochemical energy storage becomes a viable alternate means of exploiting solar energy.

  18. Validation of CFD simulation for flat plate solar energy collector

    Energy Technology Data Exchange (ETDEWEB)

    Selmi, Mohamed; Al-Khawaja, Mohammed J.; Marafia, Abdulhamid [Department of Mechanical Engineering, University of Qatar, P.O. Box 2713, Doha, State of Qatar (Qatar)

    2008-03-15

    The problem of flat plate solar energy collector with water flow is simulated and analyzed using computational fluid dynamics (CFD) software. The considered case includes the CFD modeling of solar irradiation and the modes of mixed convection and radiation heat transfer between tube surface, glass cover, side walls, and insulating base of the collector as well as the mixed convective heat transfer in the circulating water inside the tube and conduction between the base and tube material. The collector performance, after obtaining 3-D temperature distribution over the volume of the body of the collector, was studied with and without circulating water flow. An experimental model was built and experiments were performed to validate the CFD model. The outlet temperature of water is compared with experimental results and there is a good agreement. (author)

  19. Progress in passive solar energy systems. Volume 8. Part 1

    Energy Technology Data Exchange (ETDEWEB)

    Hayes, J.; Andrejko, D.A.

    1983-01-01

    This book presents the papers given at a conference sponsored by the US DOE, the Solar Energy Research Institute, SolarVision, Inc., and the Southern California Solar Energy Society. The topics considered at the conference included sizing solar energy systems for agricultural applications, a farm scale ethanol production plant, the EEC wind energy RandD program, the passive solar performance assessment of an earth-sheltered house, the ARCO 1 MW photovoltaic power plant, the performance of a dendritic web photovoltaic module, second generation point focused concentrators, linear fresnel lens concentrating photovoltaic collectors, photovoltaic conversion efficiency, amorphous silicon thin film solar cells, a photovoltaic system for a shopping center, photovoltaic power generation for the utility industry, spectral solar radiation, and the analysis of insolation data.

  20. U.S. Department of Energy Solar Decathlon

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-12-16

    The U.S. Department of Energy Solar Decathlon is an award-winning program that challenges 20 collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive. In addition to showcasing the cost savings and environmental benefits of market-ready solar technologies, the event encourages participating students to think in new ways about incorporating practical, affordable clean-energy solutions into residential applications.

  1. Solar PV Energy Conversion System and its Configurations

    Directory of Open Access Journals (Sweden)

    Ahteshamul Haque

    2016-02-01

    Full Text Available Solar PV based energy conversion system is now used in commercial and residential buildings. Advancements in Power electronics leads the researchers to enhance the use of solar application in various configurations. These configurations may be used to utilize the energy optimally. The main objective of this paper is to present an overview of the various configurations of solar PV energy conversion system

  2. Solar energy system economic evaluation for Seeco Lincoln, Lincoln, Nebraska

    Science.gov (United States)

    1980-01-01

    The economic analysis of the solar energy system that was installed at Lincoln, Nebraska is developed for this and four other sites typical of a wide range of environmental and economic conditions in the continental United States. This analysis is accomplished based on the technical and economic models in the f chart design procedure with inputs based on the characteristics of the installed system and local conditions. The results are expressed in terms of the economic parameters of present worth of system cost over projected twenty year life: life cycle savings, year of positive savings and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables is also investigated.

  3. Solar energy system economic evaluation: IBM System 4, Clinton, Mississippi

    Science.gov (United States)

    1980-01-01

    An economic analysis of the solar energy system was developed for five sites, typical of a wide range of environmental and economic conditions in the continental United States. The analysis was based on the technical and economic models in the F-chart design procedure, with inputs based on the characteristic of the installed system and local conditions. The results are of the economic parameters of present worth of system cost over a 20 year time span: life cycle savings, year of positive savings and year of payback for the optimized solar energy system at each of the analysis sites. The sensitivity of the economic evaluation to uncertainties in constituent system and economic variables is also investigated.

  4. 76 FR 54454 - Issuance of Loan Guarantee to Genesis Solar, LLC, for the Genesis Solar Energy Project

    Science.gov (United States)

    2011-09-01

    ... Issuance of Loan Guarantee to Genesis Solar, LLC, for the Genesis Solar Energy Project AGENCY: U.S... Genesis Solar, LLC, for construction and startup of the Genesis Solar Energy Project (GSEP), a 250... Statement for the Genesis Solar Energy Project, Riverside County, California (75 Federal Register...

  5. Techno-economic and life-cycle modeling and analysis of various energy storage technologies coupled with a solar photovoltaic array

    Science.gov (United States)

    Peterson, Brian Andrew

    Renewable energies, such as wind and solar, are a growing piece of global energy consumption. The chief motivation to develop renewable energy is two-fold: reducing carbon dioxide emissions and reducing dependence on diminishing fossil fuel supplies. Energy storage is critical to the growth of renewable energy because it allows for renewably-generated electricity to be consumed at times when renewable sources are unavailable, and it also enhances power quality (maintaining voltage and frequency) on an electric grid which becomes increasingly unstable as more renewable energy is added. There are numerous means of storing energy with different advantages, but none has emerged as the clear solution of choice for renewable energy storage. This thesis attempts to explore the current and developing state of energy storage and how it can be efficiently implemented with crystalline silicon solar photovotlaics, which has a minimum expected lifetime of 25 years assumed in this thesis. A method of uniformly comparing vastly different energy storage technologies using empirical data was proposed. Energy storage technologies were compared based on both economic valuation over the system life and cradle-to-gate pollution rates for systems with electrochemical batteries. For stationary, non-space-constrained settings, lead-acid batteries proved to be the most economical. Carbon-enhanced lead-acid batteries were competitive, showing promise as an energy storage technology. Lithium-ion batteries showed the lowest pollution rate of electrochemical batteries examined, but both lithium-ion and lead-acid batteries produce comparable carbon dioxide to coal-derived electricity.

  6. Analysis of Energy Efficiency in Dynamic Optical Networks Employing Solar Energy Sources

    DEFF Research Database (Denmark)

    Wang, Jiayuan; Fagertun, Anna Manolova; Ruepp, Sarah Renée

    2013-01-01

    The paper presents energy efficient routing in dynamic optical networks, where solar energy sources are employed for the network nodes. Different parameters are evaluated, including the number of nodes that have access to solar energy sources, the different maximum solar output power, traffic type...

  7. The solar energy in Israel; L'energie solaire en Israel

    Energy Technology Data Exchange (ETDEWEB)

    Bocquet, L

    2004-05-01

    The solar energy is an important characteristic of Israel, listed in its history and its development. This document presents the solar energy applications in the country in many domains: the solar energy for residential houses, the applications in the agricultural and industrial sectors and the research and development programs. (A.L.B.)

  8. Green cooperative communication network using solar energy sources

    National Research Council Canada - National Science Library

    Sanjay kumar; jaya diptilal; S.V charhate

    2016-01-01

    ..., renewable portfolio standards and voluntary green power programs in many countries. Potential expansion of carbon credit markets also would provide additional incentives to solar energy deployment...

  9. Electrifying Greece with solar and wind energy

    Directory of Open Access Journals (Sweden)

    Mentis Dimitris

    2014-01-01

    Full Text Available Ensuring energy security, reducing GHG emissions and boosting the competitiveness of a country’s economy by attracting investments and technical knowhow are of paramount importance considering the targets of “20-20-20” set by the European community. Being the cradle of civilization, Greece appears today as a country caught in a prolonged hard economic and social crisis, the way out of which its citizens are looking forward as well as the entire European Union. Establishment of the leading renewable energy sources like solar and wind in Greece will not only increase the independence of its own electrification but will also provide with a foundation for developing the market of international trade of “green” energy. This paper initially highlights the current status of photovoltaics and wind turbines in Greece. Furthermore, this study evaluates whether a higher penetration of the above mentioned green energy sources would have positive impact in the economy of the country or not and in what extent they could decline the CO2 emissions until 2020, comparing to the corresponding levels in 2010.

  10. Large solar energy systems within IEA task 14

    NARCIS (Netherlands)

    Geus, A.C. de; Isakson, P.; Bokhoven, T.P.; Vanoli, K.; Tepe, R.

    1996-01-01

    Within IEA Task 14 (Advanced Solar Systems) a working group was established dealing with large advanced solar energy systems (the Large Systems Working group). The goal of this working group was to generate a common base of experiences for the design and construction of advanced large solar systems.

  11. Large solar energy systems within IEA task 14

    NARCIS (Netherlands)

    Geus, A.C. de; Isakson, P.; Bokhoven, T.P.; Vanoli, K.; Tepe, R.

    1996-01-01

    Within IEA Task 14 (Advanced Solar Systems) a working group was established dealing with large advanced solar energy systems (the Large Systems Working group). The goal of this working group was to generate a common base of experiences for the design and construction of advanced large solar systems.

  12. Models of Solar Irradiance Variations: Current Status

    Indian Academy of Sciences (India)

    Natalie A. Krivova; Sami K. Solanki

    2008-03-01

    Regular monitoring of solar irradiance has been carried out since 1978 to show that solar total and spectral irradiance varies at different time scales. Whereas variations on time scales of minutes to hours are due to solar oscillations and granulation, variations on longer time scales are driven by the evolution of the solar surface magnetic field. Here the most recent advances in modelling of solar irradiance variations on time scales longer than a day are briefly reviewed.

  13. California solar energy study: decision-analysis panel report

    Energy Technology Data Exchange (ETDEWEB)

    Margolin, J.B.; Misch, M.R.

    1979-09-01

    In order to investigate motivations behind an individual's decision to purchase or not to purchase a solar energy system for a home, the California Energy Commission initiated a comprehensive survey program to analyze, in some depth, attitudes toward solar energy use. As part of that program, the CEC contracted for a series of panels comprised of homogenous groups of individuals who were not solar adopters, to probe for underlying attitudes about solar and, through the group dynamics process, elicit information which generally cannot be obtained using a standard questionnaire. The results shed additional light on consumer perceptions about the energy situation, the solar industry, economics, government's role and acceptance of the technology which, in turn, affect the individual's decision to adopt or not to adopt a solar energy device.

  14. Bidirectional control system for energy flow in solar powered flywheel

    Science.gov (United States)

    Nola, Frank J. (Inventor)

    1987-01-01

    An energy storage system for a spacecraft is provided which employs a solar powered flywheel arrangement including a motor/generator which, in different operating modes, drives the flywheel and is driven thereby. A control circuit, including a threshold comparator, senses the output of a solar energy converter, and when a threshold voltage is exceeded thereby indicating the availability of solar power for the spacecraft loads, activates a speed control loop including the motor/generator so as to accelerate the flywheel to a constant speed and thereby store mechanical energy, while also supplying energy from the solar converter to the loads. Under circumstances where solar energy is not available and thus the threshold voltage is not exceeded, the control circuit deactivates the speed control loop and activates a voltage control loop that provides for operation of the motor as a generator so that mechanical energy from the flywheel is converted into electrical energy for supply to the spacecraft loads.

  15. Energy collector for collecting solar energy and the like

    Energy Technology Data Exchange (ETDEWEB)

    Bansal, J.M.; Kumar, A.

    1978-10-03

    A solar energy collector connectable with a fluid-circulating system is contained in a plenum within an insulative housing and has a plurality of generally parallel, heat-absorbing conduits extending between intake and outlet manifolds and confronting the sun or other heat source through a transparent window, each conduit being separated from an adjacent conduit by an intervening slot. Positioned below the conduits is a heat-absorbing tank which is connected in fluid-flow relationship with the outlet manifold and also with the circulation system so that a heat-transfer medium may flow continuously between the energy collector and the circulation system. The tank receives radiant energy through the slots and after absorbing some of the radiation reflects the remaining portion upwardly to the conduits to thereby increase radiation intensity on and heat absorption by the conduits. Multiple reflections between tank and conduits further increase energy absorption both by tank and conduit. The conduits may be of round cross section or may have a planar heat-absorbing surface facing the sun and an arcuate, convex surface facing the tank. The tank may be provided with a plurality of arcuate troughs, a trough underlying and paralleling each conduit to both absorb energy and reflect energy toward the overlying conduit. The conduits may be provided with internal air ducts which communicate with the hot-air plenum and permit heat from the hot air to be transferred through the duct walls and to the fluid medium within the conduits.

  16. Improving the Energy Management of a Solar Electric Vehicle

    Directory of Open Access Journals (Sweden)

    GUNESER, M. T.

    2015-11-01

    Full Text Available A solar electric vehicle (SEV is an electric vehicle (EV with onboard photovoltaic cells charging a set of batteries for extended driving range. This study aimed to improve the energy management system of a SEV, called YILDIZ, using a fuzzy logic control system (FLC. A MATLAB based simulation model of three basic components of a solar car: solar cell modules, batteries and motor drive system was performed. An original FLC was developed. For proving its applicability, the performances of the SEV were tested by simulation, in accordance with the standard test drive cycle ECE-15. The characteristics obtained with the original Proportional Integral Fuzzy Logic Control (PI-FLC were compared with those obtained with a classical Proportional Integral (PI controller. Using the designed model, we calculated the range of YILDIZ with and without PV feeding which gave us an opportunity to study and compare both SEV and EV models on real race-track situation. Then the optimum speed, at any time, which enabled the vehicle to reach a chosen destination as quickly as possible, while fully using the available energy, was calculated. Proposed solutions tested on YILDIZ. Results of simulations were compared with YILDIZ run on the Formula-G race track in Izmit, Turkey.

  17. Foaming of aluminium-silicon alloy using concentrated solar energy

    Energy Technology Data Exchange (ETDEWEB)

    Cambronero, L.E.G.; Ruiz-Roman, J.M. [Grupo de Materiales Hibridos, ETSIM-UPM, Madrid, Rios Rosas 21, 28003 Madrid (Spain); Canadas, I.; Martinez, D. [Plataforma Solar de Almeria, CIEMAT, P.O. Box 22, 04200 Tabernas (Almeria) (Spain)

    2010-06-15

    Solar energy is used for the work reported here as a nonconventional heating system to produce aluminium foam from Al-Si alloy precursors produced by powder metallurgy. A commercial precursor in cylindrical bars enclosed in a stainless-steel mould was heated under concentrated solar radiation in a solar furnace with varied heating conditions (heating rate, time, and temperature). Concentrated solar energy close to 300 W/cm{sup 2} on the mould is high enough to achieve complete foaming after heating for only 200 s. Under these conditions, the density and pore distribution in the foam change depending on the solar heating parameters and mould design. (author)

  18. Production of solar radiation bankable datasets from high-resolution solar irradiance derived with dynamical downscaling Numerical Weather prediction model

    Directory of Open Access Journals (Sweden)

    Yassine Charabi

    2016-11-01

    Full Text Available A bankable solar radiation database is required for the financial viability of solar energy project. Accurate estimation of solar energy resources in a country is very important for proper siting, sizing and life cycle cost analysis of solar energy systems. During the last decade an important progress has been made to develop multiple solar irradiance database (Global Horizontal Irradiance (GHI and Direct Normal Irradiance (DNI, using satellite of different resolution and sophisticated models. This paper assesses the performance of High-resolution solar irradiance derived with dynamical downscaling Numerical Weather Prediction model with, GIS topographical solar radiation model, satellite data and ground measurements, for the production of bankable solar radiation datasets. For this investigation, NWP model namely Consortium for Small-scale Modeling (COSMO is used for the dynamical downscaling of solar radiation. The obtained results increase confidence in solar radiation data base obtained from dynamical downscaled NWP model. The mean bias of dynamical downscaled NWP model is small, on the order of a few percents for GHI, and it could be ranked as a bankable datasets. Fortunately, these data are usually archived in the meteorological department and gives a good idea of the hourly, monthly, and annual incident energy. Such short time-interval data are valuable in designing and operating the solar energy facility. The advantage of the NWP model is that it can be used for solar radiation forecast since it can estimate the weather condition within the next 72–120 hours. This gives a reasonable estimation of the solar radiation that in turns can be used to forecast the electric power generation by the solar power plant.

  19. Integration of Wind Energy and Solar Energy in a DC Microgrid Using Fuzzy Logic Control

    Science.gov (United States)

    Jajula, Harshavardhan

    The significance of wind and solar energy as renewable sources for electric power generation has been rapidly increasing. The current project presents a model subsystem that integrates wind and solar energy sources to power a Direct Current (DC) microgrid, along with a backup Battery Energy Storage System (BESS) and a supercapacitor. The microgrid is used for the charging of electric vehicles locally, to supply power to the main grid, and to meet other local demands. The model compares the effectiveness of two control methods: Fuzzy Logic Control (FLC) and Proportional plus Integral control (PI). Simulation results show that the FLC is more efficient in regulating the grid power and DC bus voltage, and at the same time, it is simpler to implement, as compared to the PI controller.

  20. National solar energy education directory. Second edition

    Energy Technology Data Exchange (ETDEWEB)

    Corcoleotes, G; Cronin, S; Kramer, K; O& #x27; Connor, K

    1980-01-01

    The information contained in this directory is derived from responses to a national survey of educational institutions and organizations involved in solar energy educational activities beyond the secondary school level. Phone calls and follow-up mail requests were used to gather additional information when necessary. Every survey instrument was read, coded, and edited before entry into the data base from which this directory was produced. The Directory is organized alphabetically by state. Institutions and organizations within each state are categorized according to type (Colleges and Universities, Junior/Community Colleges, Vocational/Technical Schools, and Other Educational Institutions and Organizations) and listed alphabetically within these categories. Within each institutional listing the amount of information provided will vary according to the completeness of the survey response received from that institution. (MHR)

  1. Modeling and analysis of solar distributed generation

    Science.gov (United States)

    Ortiz Rivera, Eduardo Ivan

    Recent changes in the global economy are creating a big impact in our daily life. The price of oil is increasing and the number of reserves are less every day. Also, dramatic demographic changes are impacting the viability of the electric infrastructure and ultimately the economic future of the industry. These are some of the reasons that many countries are looking for alternative energy to produce electric energy. The most common form of green energy in our daily life is solar energy. To convert solar energy into electrical energy is required solar panels, dc-dc converters, power control, sensors, and inverters. In this work, a photovoltaic module, PVM, model using the electrical characteristics provided by the manufacturer data sheet is presented for power system applications. Experimental results from testing are showed, verifying the proposed PVM model. Also in this work, three maximum power point tracker, MPPT, algorithms would be presented to obtain the maximum power from a PVM. The first MPPT algorithm is a method based on the Rolle's and Lagrange's Theorems and can provide at least an approximate answer to a family of transcendental functions that cannot be solved using differential calculus. The second MPPT algorithm is based on the approximation of the proposed PVM model using fractional polynomials where the shape, boundary conditions and performance of the proposed PVM model are satisfied. The third MPPT algorithm is based in the determination of the optimal duty cycle for a dc-dc converter and the previous knowledge of the load or load matching conditions. Also, four algorithms to calculate the effective irradiance level and temperature over a photovoltaic module are presented in this work. The main reasons to develop these algorithms are for monitoring climate conditions, the elimination of temperature and solar irradiance sensors, reductions in cost for a photovoltaic inverter system, and development of new algorithms to be integrated with maximum

  2. (seminario usos de la energia solar en la vivienda) solar energy applications for dwellings. Seminar 17-19 nov 80

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    Contents include: National Ecoplan; National Urban Development Plan; The National Housing Program and the Use of Solar Systems and not Conventional Energies in Human Settlements; National Infrastructure for the Development of Solar Energy; Plans to Incorporate Solar Energy Systems into Mexican Communities; General Panorama of Solar Energy Projects Being Carried out in Mexico; and Recent Demonstration Projects in Mexico.

  3. Return currents and energy transport in the solar flaring atmosphere

    CERN Document Server

    Codispoti, Anna; Piana, Michele; Pinamonti, Nicola

    2013-01-01

    According to a standard ohmic perspective, the injection of accelerated electrons into the flaring region violates local charge equilibrium and therefore, in response, return currents are driven by an electric field to equilibrate such charge violation. In this framework, the energy loss rate associated to these local currents has an ohmic nature and significantly shortens the acceleration electron path. In the present paper we adopt a different viewpoint and, specifically, we study the impact of the background drift velocity on the energy loss rate of accelerated electrons in solar flares. We first utilize the Rutherford cross-section to derive the formula of the energy loss rate when the collisional target has a finite temperature and the background instantaneously and coherently moves up to equilibrate the electron injection. We then use the continuity equation for electrons and imaging spectroscopy data provided by RHESSI to validate this model. Specifically, we show that this new formula for the energy l...

  4. Carbon nanotube-based heterostructures for solar energy applications.

    Science.gov (United States)

    Wang, Lei; Liu, Haiqing; Konik, Robert M; Misewich, James A; Wong, Stanislaus S

    2013-10-21

    One means of combining the unique physical and chemical properties of both carbon nanotubes and complementary material motifs (such as metal sulfide quantum dots (QDs), metal oxide nanostructures, and polymers) can be achieved by generating carbon nanotube (CNT)-based heterostructures. These materials can be subsequently utilized as novel and interesting constituent building blocks for the assembly of functional light energy harvesting devices and because of their architectural and functional flexibility, can potentially open up novel means of using and taking advantage of existing renewable energy sources. In this review, we present the reliable and reproducible synthesis of several unique model CNT-based heterostructured systems as well as include an accompanying discussion about the charge transfer and energy flow properties of these materials for their potential incorporation into a range of practical solar energy conversion devices.

  5. The Solar Solution: Tracking the Sun with Low Energy Neutrinos

    CERN Document Server

    Hartman, Nicole

    2016-01-01

    As neutrinos become a significant background for projected dark matter experiments, the community will become concerned with determining if events counted in a dark matter experiment are good dark matter candidates or low-energy neutrinos from astrophysical sources. We investigate the feasibility of using neutrino-electron scattering in a terrestrial detector medium as a means to determine the flight direction of the original, low-energy solar neutrino.Using leading-order weak interactions in the Standard Model and constrains from energy and momentum conservation, we developed a simple simulation that suggests that 68% of the time the ejected electron would be within 0.99 radians of the incident neutrino's direction. This suggests that it may be fruitful to pursue low-energy neutrino detection capability that can utilize such ejected electrons.

  6. Solar Model Parameters and Direct Measurements of Solar Neutrino Fluxes

    CERN Document Server

    Bandyopadhyay, A; Goswami, S; Petcov, S T; Bandyopadhyay, Abhijit; Choubey, Sandhya; Goswami, Srubabati

    2006-01-01

    We explore a novel possibility of determining the solar model parameters, which serve as input in the calculations of the solar neutrino fluxes, by exploiting the data from direct measurements of the fluxes. More specifically, we use the rather precise value of the $^8B$ neutrino flux, $\\phi_B$ obtained from the global analysis of the solar neutrino and KamLAND data, to derive constraints on each of the solar model parameters on which $\\phi_B$ depends. We also use more precise values of $^7Be$ and $pp$ fluxes as can be obtained from future prospective data and discuss whether such measurements can help in reducing the uncertainties of one or more input parameters of the Standard Solar Model.

  7. Space satellite power system. [conversion of solar energy by photovoltaic solar cell arrays

    Science.gov (United States)

    Glaser, P. E.

    1974-01-01

    The concept of a satellite solar power station was studied. It is shown that it offers the potential to meet a significant portion of future energy needs, is pollution free, and is sparing of irreplaceable earth resources. Solar energy is converted by photovoltaic solar cell arrays to dc energy which in turn is converted into microwave energy in a large active phased array. The microwave energy is beamed to earth with little attenuation and is converted back to dc energy on the earth. Economic factors are considered.

  8. Efficiency of liquid flat-plate solar energy collector with solar tracking system

    Directory of Open Access Journals (Sweden)

    Chekerovska Marija

    2015-01-01

    Full Text Available An extensive testing programme is performed on a solar collector experimental set-up, installed on a location in Shtip (Republic of Macedonia, latitude 41º 45’ and longitude 22º 12’, in order to investigate the effect of the sun tracking system implementation on the collector efficiency. The set-up consists of two flat plate solar collectors, one with a fixed surface tilted at 30о towards the South, and the other one equipped with dual-axis rotation system. The study includes development of a 3-D mathematical model of the collectors system and a numerical simulation programme, based on the computational fluid dynamics (CFD approach. The main aim of the mathematical modelling is to provide information on conduction, convection and radiation heat transfer, so as to simulate the heat transfer performances and the energy capture capabilities of the fixed and moving collectors in various operating modes. The feasibility of the proposed method was confirmed by experimental verification, showing significant increase of the daily energy capture by the moving collector, compared to the immobile collector unit. The comparative analysis demonstrates a good agreement between the experimental and numerically predicted results at different running conditions, which is a proof that the presented CFD modelling approach can be used for further investigations of different solar collectors configurations and flow schemes.

  9. Thermodynamic analysis of a Rankine cycle powered vapor compression ice maker using solar energy

    National Research Council Canada - National Science Library

    Hu, Bing; Bu, Xianbiao; Ma, Weibin

    2014-01-01

    To develop the organic Rankine-vapor compression ice maker driven by solar energy, a thermodynamic model was developed and the effects of generation temperature, condensation temperature, and working...

  10. Thermodynamic Analysis of a Rankine Cycle Powered Vapor Compression Ice Maker Using Solar Energy

    National Research Council Canada - National Science Library

    Hu, Bing; Bu, Xianbiao; Ma, Weibin

    2014-01-01

      To develop the organic Rankine-vapor compression ice maker driven by solar energy, a thermodynamic model was developed and the effects of generation temperature, condensation temperature, and working...

  11. Solar and Geothermal Energy: New Competition for the Atom

    Science.gov (United States)

    Carter, Luther J.

    1974-01-01

    Describes new emphasis on research into solar and geothermal energy resources by governmental action and recent legislation and the decreased emphasis on atomic power in supplementing current energy shortages. (BR)

  12. Solar and Geothermal Energy: New Competition for the Atom

    Science.gov (United States)

    Carter, Luther J.

    1974-01-01

    Describes new emphasis on research into solar and geothermal energy resources by governmental action and recent legislation and the decreased emphasis on atomic power in supplementing current energy shortages. (BR)

  13. High heat flux engineering in solar energy applications

    Energy Technology Data Exchange (ETDEWEB)

    Cameron, C.P.

    1993-07-01

    Solar thermal energy systems can produce heat fluxes in excess of 10,000 kW/m{sup 2}. This paper provides an introduction to the solar concentrators that produce high heat flux, the receivers that convert the flux into usable thermal energy, and the instrumentation systems used to measure flux in the solar environment. References are incorporated to direct the reader to detailed technical information.

  14. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  15. Application of solar energy to air-conditioning

    Science.gov (United States)

    Harstad, A. J.; Nash, J. M.

    1978-01-01

    Results of survey of application of solar energy to air-conditioning systems are summarized in report. Survey reviewed air-conditioning techniques that are most likely to find residential applications and that are compatible with solar-energy systems being developed.

  16. Solar and wind energy potential and utilization in Pakistan

    Energy Technology Data Exchange (ETDEWEB)

    Raja, I.A. (Balochistan Univ., Quetta (Pakistan). Dept. of Physics); Abro, R.S. (Sheffield Univ. (United Kingdom). School of Architecture Studies)

    1994-08-01

    This paper identifies the potentials of solar and wind energy. The prime sites for wind are coastal area, arid zone and hill terrains. Solar energy is abundant over most parts of the country, the maximum being received over Quetta valley. (author)

  17. Wind loads on solar energy systems, mounted on flat roofs

    NARCIS (Netherlands)

    Geurts, C.P.W.; Bentum, C.A. van; Blackmore, P.

    2005-01-01

    Wind loads on solar energy systems are not covered by current wind loading standards. This paper describes results of a parametric study into the wind loads on solar energy systems, which are placed on flat roofs. Wind tunnel measurements have been carried out on a number of configurations. The resu

  18. Solar energy powered microbial fuel cell with a reversible bioelectrode

    NARCIS (Netherlands)

    Strik, D.P.B.T.B.; Hamelers, H.V.M.; Buisman, C.J.N.

    2010-01-01

    The solar energy powered microbial fuel cell is an emerging technology for electricity generation via electrochemically active microorganisms fueled by solar energy via in situ photosynthesized metabolites from algae, cyanobacteria, or living higher plants. A general problem with microbial fuel cell

  19. Green cooperative communication network using solar energy sources

    Directory of Open Access Journals (Sweden)

    Sanjay kumar

    2016-08-01

    Full Text Available Solar energy has experienced phenomenal growth in recent years due to both technological improvements resulting in cost reductions and government policies supportive of renewable energy development and utilization. This study analyzes the technical, economic and policy aspects of solar energy development and deployment. While the cost of solar energy has declined rapidly in the recent past, it still remains much higher than the cost of conventional energy technologies. Like other renewable energy technologies, solar energy benefits from fiscal and regulatory incentives and mandates, including tax credits and exemptions, feed-in-tariff, preferential interest rates, renewable portfolio standards and voluntary green power programs in many countries. Potential expansion of carbon credit markets also would provide additional incentives to solar energy deployment; however, the scale of incentives provided by the existing carbon market instruments, such as the Clean Development Mechanism of the Kyoto Protocol, is limited. Despite the huge technical potential, development and large-scale, market-driven deployment of solar energy technologies worldwide still has to overcome a number of technical and financial barriers. Unless these barriers are overcome, maintaining and increasing electricity supplies from solar energy will require continuation of potentially costly policy support. Indexing terms/

  20. DOE Solar Energy Technologies Program FY 2006 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    2007-07-01

    The DOE Solar Energy Technologies Program FY 2006 Annual Report chronicles the R&D results of the U.S. Department of Energy Solar Energy Technologies Program for Fiscal Year 2005. In particular, the report describes R&D performed by the Program's national laboratories (National Renewable Energy Laboratory, Sandia National Laboratories, Oak Ridge National Laboratory, and Brookhaven National Laboratory) and university and industry partners.

  1. DOE Solar Energy Technologies Program FY 2005 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    2006-03-01

    The DOE Solar Energy Technologies Program FY 2005 Annual Report chronicles the R&D results of the U.S. Department of Energy Solar Energy Technologies Program for Fiscal Year 2005. In particular, the report describes R&D performed by the Program?s national laboratories (National Renewable Energy Laboratory, Sandia National Laboratories, Oak Ridge National Laboratory, and Brookhaven National Laboratory) and university and industry partners.

  2. DOE Solar Energy Technologies Program 2007 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    2008-07-01

    The DOE Solar Energy Technologies Program FY 2007 Annual Report chronicles the R&D results of the U.S. Department of Energy Solar Energy Technologies Program from October 2006 to September 2007. In particular, the report describes R&D performed by the Program's national laboratories (National Renewable Energy Laboratory, Sandia National Laboratories, Oak Ridge National Laboratory, and Brookhaven National Laboratory) and university and industry partners.

  3. DOE Solar Energy Technologies Program: FY 2004 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    2005-10-01

    The DOE Solar Energy Technologies Program FY 2004 Annual Report chronicles the R&D results of the U.S. Department of Energy Solar Energy Technologies Program for Fiscal Year 2004. In particular, the report describes R&D performed by the Program's national laboratories (National Renewable Energy Laboratory, Sandia National Laboratories, Oak Ridge National Laboratory, and Brookhaven National Laboratory) and university and industry partners.

  4. Solar Kilns: Feasibility of Utilizing Solar Energy for Drying Lumber in Developing Countries,

    Science.gov (United States)

    1977-01-01

    evaluation of shelf type solar driers. Sol. Energy 16(2):81-88. N Selcuk, M. K. 1967. Final report of the solar fruit dryer . Cooperation Medi- terraneenne...at one dryer orientation (long axis north-south) from 30 percent to 10 percent moisture content. 49 Table 15.--Greenhouse-type solar kiln capacity...out the success or failure of some design features, construction details, and applications of solar dryers . Feasibility _; estimates concluded that

  5. Solar Coronal Jets: Observations, Theory, and Modeling

    CERN Document Server

    Raouafi, N E; Pariat, E; Young, P R; Sterling, A C; Savcheva, A; Shimojo, M; Moreno-Insertis, F; DeVore, C R; Archontis, V; Török, T; Mason, H; Curdt, W; Meyer, K; Dalmasse, K; Matsui, Y

    2016-01-01

    Coronal jets represent important manifestations of ubiquitous solar transients, which may be the source of significant mass and energy input to the upper solar atmosphere and the solar wind. While the energy involved in a jet-like event is smaller than that of "nominal" solar flares and coronal mass ejections (CMEs), jets share many common properties with these phenomena, in particular, the explosive magnetically driven dynamics. Studies of jets could, therefore, provide critical insight for understanding the larger, more complex drivers of the solar activity. On the other side of the size-spectrum, the study of jets could also supply important clues on the physics of transients close or at the limit of the current spatial resolution such as spicules. Furthermore, jet phenomena may hint to basic process for heating the corona and accelerating the solar wind; consequently their study gives us the opportunity to attack a broad range of solar-heliospheric problems.

  6. Assessment of wind and solar power in global low-carbon energy scenarios: An introduction

    Energy Technology Data Exchange (ETDEWEB)

    Luderer, Gunnar; Pietzcker, Robert C.; Carrara, Samuel; de Boer, Harmen Sytze; Fujimori, Shinichiro; Johnson, Nils; Mima, Silvana; Arent, Douglas

    2017-04-07

    This preface introduces the special section on the assessment of wind and solar in global low-carbon energy scenarios. The special section documents the results of a coordinated research effort to improve the representation of variable renewable energies (VRE), including wind and solar power, in Integrated Assessment Models (IAM) and presents an overview of the results obtained in the underlying coordinated model inter-comparison exercise.

  7. Diffusion of solar energy technologies in the new-construction market: A survey of new solar-home and conventional-home buyers

    Science.gov (United States)

    Rains, D.; Dunipace, D.; Woo, C. K.

    1981-02-01

    Consumer motivations for choosing a solar energy equipped home when the nonsolar or conventional model was available were investigated. The approach was to test the relative importance of demographic, dwelling unit, and heating system characteristics in household decisions to purchase a home equipped with solar energy devices. Two statistical models were developed: one to examine the relationship between the types of home buyers (as an identifiable market segment) and the decision to purchase a solar home; and the other to compare the energy use of solar vs. conventional homes selected in the sample.

  8. How to use solar energy in the home and garden? Instructions and suggestions for easy self-construction of solar-powered systems: garden lighting, fountains, solar accumulators and solar motors; Wie nutze ich Solarenergie in Haus und Garten?. Bauanleitungen und Anregungen zum leichten Selbstbau von Solaranlagen wie z.B. Solar-Gartenbeleuchtung, Solar-Springbrunnen, Solar-Akkumulatoren, Solar-Elektromotoren

    Energy Technology Data Exchange (ETDEWEB)

    Hanus, B.

    1995-08-01

    The book reports on solar energy utilization: - solar energy and photovoltaics, - solar cell modules for self-construction, - self-sufficient solar power supply, - solar-powered pumps and engines, - ventilation and cooling using solar power, - heating using solar power, - garden lighting using solar power. (HW) [Deutsch] Das Buch berichtet ueber die Nutzung von Solarenergie: - Solarenergie und Photovoltaic; - Solarzellenmodule in Selbstbau; - Selbstversorgung mit Solarstrom; - Solar-Pumpen und -Motoren; - Lueften und Kuehlung mit Solarstrom; - Heizen mit Solarstrom; - Gartenbeleuchtung mit Solarstrom. (orig.)

  9. Solar Energy Technologies Program Newsletter - July 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-07-01

    This quarterly newsletter is intended for participants and stakeholders in the DOE Solar Program. The content includes features on technology development, market transformation, and policy analysis for solar. Highlights include solar industry updates, DOE funding opportunity announcements and awards, and national laboratory technology developments.

  10. Solar Energy Technologies Program Newsletter - September 2009

    Energy Technology Data Exchange (ETDEWEB)

    None

    2009-10-01

    This quarterly newsletter is intended for participants and stakeholders in the DOE Solar Program. The content includes features on technology development, market transformation, and policy analysis for solar. Highlights include solar industry updates, DOE funding opportunity announcements and awards, and national laboratory technology developments.

  11. 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...

  12. Spectral light management for solar energy conversion systems

    Directory of Open Access Journals (Sweden)

    Stanley Cameron

    2016-06-01

    Full Text Available Due to the inherent broadband nature of the solar radiation, combined with the narrow spectral sensitivity range of direct solar to electricity devices, there is a massive opportunity to manipulate the solar spectrum to increase the functionality and efficiency of solar energy conversion devices. Spectral splitting or manipulation facilitates the efficient combination of both high-temperature solar thermal systems, which can absorb over the entire solar spectrum to create heat, and photovoltaic cells, which only convert a range of wavelengths to electricity. It has only recently been possible, with the development of nanofabrication techniques, to integrate micro- and nano-photonic structures as spectrum splitters/manipulators into solar energy conversion devices. In this paper, we summarize the recent developments in beam splitting techniques, and highlight some relevant applications including combined PV-thermal collectors and efficient algae production, and suggest paths for future development in this field.

  13. Spectral light management for solar energy conversion systems

    Science.gov (United States)

    Stanley, Cameron; Mojiri, Ahmad; Rosengarten, Gary

    2016-06-01

    Due to the inherent broadband nature of the solar radiation, combined with the narrow spectral sensitivity range of direct solar to electricity devices, there is a massive opportunity to manipulate the solar spectrum to increase the functionality and efficiency of solar energy conversion devices. Spectral splitting or manipulation facilitates the efficient combination of both high-temperature solar thermal systems, which can absorb over the entire solar spectrum to create heat, and photovoltaic cells, which only convert a range of wavelengths to electricity. It has only recently been possible, with the development of nanofabrication techniques, to integrate micro- and nano-photonic structures as spectrum splitters/manipulators into solar energy conversion devices. In this paper, we summarize the recent developments in beam splitting techniques, and highlight some relevant applications including combined PV-thermal collectors and efficient algae production, and suggest paths for future development in this field.

  14. The energy spectra of anomalous oxygen at the time of two successive solar minima

    CERN Document Server

    Kondratyeva, M A; Tretyakova, S P; Zhuravlev, D A

    1999-01-01

    The energy spectra of anomalous oxygen have been determined from nuclear track detectors exposed aboard the Earth-orbiting satellites at altitudes ranging from approx 250-400 km in two consecutive solar minimum periods of 1986-1987 and 1994-1995 with opposite polarity of the solar magnetic field. A comparison of the spectra shows no contradiction to current drift models.

  15. Energy and exergy performance investigation of transcritical CO2-based Rankine cycle powered by solar energy

    Institute of Scientific and Technical Information of China (English)

    ZHANG XinRong; LI XiaoJuan

    2012-01-01

    A comprehensive performance evaluation of a solar assisted transcritical CO2-based Rankine cycle system is made with exergy analysis method.The actual thermal data taken from the all-day experiment of the system are utilized to determine energy transfer and the exergy destructions in each component of the system.In addition,a hypothetical carbon dioxide expansion turbine is introduced,then two thermodynamic models for solar transcritical carbon dioxide Rankine cycles with a throttling valve (experiment) and with an expansion turbine have been established with exergy analysis method.The obtained results clearly show that solar collector contributes the largest share to system irreversibility and entropy generation in the all-day working state,and the exergy improvement potential of solar collector is the maximum in the working state.So this component should be the optimization design focus to improve system exergy effectiveness.For the cycle with the turbine,the energy efficiency and the entropy generation are not much higher than the cycle with throttling valve,but the exergy efficiency of the cycle with turbine is twice of the cycle with throttling valve.It provides more guidance when the transcritical CO2-based Rankine system is in a large-scale solar application.

  16. Nontechnical Barriers to Solar Energy Use: Review of Recent Literature

    Energy Technology Data Exchange (ETDEWEB)

    Margolis, R.; Zuboy, J.

    2006-09-01

    This paper reviews the nontechnical barriers to solar energy use, drawing on recent literature to help identify key barriers that must be addressed as part of the Technology Acceptance efforts under the U.S. Department of Energy (DOE) Solar America Initiative. A broad literature search yielded more than 400 references, which were narrowed to 19 recent documents on nontechnical barriers to the use of solar energy and other energy efficiency and renewable energy (EE/RE) technologies. Some of the most frequently identified barriers included lack of government policy supporting EE/RE, lack of information dissemination and consumer awareness about energy and EE/RE, high cost of solar and other EE/RE technologies compared with conventional energy, and inadequate financing options for EE/RE projects.

  17. How to Draw Energy Level Diagrams in Excitonic Solar Cells.

    Science.gov (United States)

    Zhu, X-Y

    2014-07-03

    Emerging photovoltaic devices based on molecular and nanomaterials are mostly excitonic in nature. The initial absorption of a photon in these materials creates an exciton that can subsequently dissociate in each material or at their interfaces to give charge carriers. Any attempt at mechanistic understanding of excitonic solar cells must start with drawing energy level diagrams. This seemingly elementary exercise, which is described in textbooks for inorganic solar cells, has turned out to be a difficult subject in the literature. The problem stems from conceptual confusion of single-particle energy with quasi-particle energy and the misleading practice of mixing the two on the same energy level diagram. Here, I discuss how to draw physically accurate energy diagrams in excitonic solar cells using only single-particle energies (ionization potentials and electron affinities) of both ground and optically excited states. I will briefly discuss current understanding on the electronic energy landscape responsible for efficient charge separation in excitonic solar cells.

  18. Solar Energy Program: Chapter from the Energy and EnvironmentalDivision Annual Report 1980

    Energy Technology Data Exchange (ETDEWEB)

    Energy and Environment Division

    1981-03-01

    -cooled and suitable for use with flat plate or higher-temperature collectors. Operation of the controls test facility and computer modeling of collector loop and building load dynamics are yielding quantitative evaluations of the performance of different control strategies for active solar-heating systems. Research is continuing on ''passive'' approaches to solar heating and cooling, where careful considerations of architectural design, construction materials, and the environment are used to moderate a building's interior climate. Computer models of passive concepts are being developed and incorporated into building energy analysis computer programs which are in the public domain. The resulting passive analysis capabilities are used in systems studies leading to design tools and in the design of commercial buildings on a case study basis. The investigation of specific passive cooling methods is an ongoing project; for example, a process is being studied in which heat-storage material would be cooled by radiation to the night sky, and would then provide ''coolness'' to the building. Laboratory personnel involved in the solar cooling, controls, and passive projects are also providing technical support to the Active Heating and Cooling Division and the Passive and Hybrid Division of DOE in developing program plans, evaluating proposals, and making technical reviews of projects at other institutions and in industry. Low-grade heat is a widespread energy resource that could make a significant contribution to energy needs if economical methods can be developed for converting it to useful work. Investigations continued this year on the feasibility of using the ''shape-memory'' alloy, Nitinol, as a basis for constructing heat engines that could operate from energy sources, such as solar-heated water, industrial waste heat, geothermal brines, and ocean thermal gradients. Several projects are investigating longer

  19. Physical aspects of ferroelectric semiconductors for photovoltaic solar energy conversion

    Science.gov (United States)

    Lopez-Varo, Pilar; Bertoluzzi, Luca; Bisquert, Juan; Alexe, Marin; Coll, Mariona; Huang, Jinsong; Jimenez-Tejada, Juan Antonio; Kirchartz, Thomas; Nechache, Riad; Rosei, Federico; Yuan, Yongbo

    2016-10-01

    Solar energy conversion using semiconductors to fabricate photovoltaic devices relies on efficient light absorption, charge separation of electron-hole pair carriers or excitons, and fast transport and charge extraction to counter recombination processes. Ferroelectric materials are able to host a permanent electrical polarization which provides control over electrical field distribution in bulk and interfacial regions. In this review, we provide a critical overview of the physical principles and mechanisms of solar energy conversion using ferroelectric semiconductors and contact layers, as well as the main achievements reported so far. In a ferroelectric semiconductor film with ideal contacts, the polarization charge would be totally screened by the metal layers and no charge collection field would exist. However, real materials show a depolarization field, smooth termination of polarization, and interfacial energy barriers that do provide the control of interface and bulk electric field by switchable spontaneous polarization. We explore different phenomena as the polarization-modulated Schottky-like barriers at metal/ferroelectric interfaces, depolarization fields, vacancy migration, and the switchable rectifying behavior of ferroelectric thin films. Using a basic physical model of a solar cell, our analysis provides a general picture of the influence of ferroelectric effects on the actual power conversion efficiency of the solar cell device, and we are able to assess whether these effects or their combinations are beneficial or counterproductive. We describe in detail the bulk photovoltaic effect and the contact layers that modify the built-in field and the charge injection and separation in bulk heterojunction organic cells as well as in photocatalytic and water splitting devices. We also review the dominant families of ferroelectric materials that have been most extensively investigated and have provided the best photovoltaic performance.

  20. 78 FR 31997 - Greatmat Technology Corp., Kentucky USA Energy, Inc., Solar Energy Ltd., and Visiphor Corp...

    Science.gov (United States)

    2013-05-28

    ... COMMISSION Greatmat Technology Corp., Kentucky USA Energy, Inc., Solar Energy Ltd., and Visiphor Corp., Order... lack of current and accurate information concerning the securities of Solar Energy Ltd. because it has... concerning the securities of Kentucky USA Energy, Inc. because it has not filed any periodic reports...

  1. Technology assessment of solar energy systems. Scenario development and methodology. Volume II

    Energy Technology Data Exchange (ETDEWEB)

    Schiffman, Y.M.

    1981-07-01

    Included are a general overview of the Technology Assessment of Solar Energy systems (TASE) project and a description of the study approach, the development of the TASE scenarios, energy and environmental assumptions, and assumptions and forecasts of the FOSSIL2 National Energy Model upon which the TASE scenarios were based. The Strategic Environmental Assessment System (SEAS) model was used to generate the analytical data base for TASE. Improvements made to SEAS to allow it to model solar and biomass energy technologies are also described.

  2. Solar energy grid integration systems : final report of the Florida Solar Energy Center Team.

    Energy Technology Data Exchange (ETDEWEB)

    Ropp, Michael (Northern Plains Power Technologies, Brookings, SD); Gonzalez, Sigifredo; Schaffer, Alan (Lakeland Electric Utilities, Lakeland, FL); Katz, Stanley (Satcon Technology Corporation, Boston, MA); Perkinson, Jim (Satcon Technology Corporation, Boston, MA); Bower, Ward Isaac; Prestero, Mark (Satcon Technology Corporation, Boston, MA); Casey, Leo (Satcon Technology Corporation, Boston, MA); Moaveni, Houtan (Florida Solar Energy Center of the University of Central Florida, Cocoa, FL); Click, David (Florida Solar Energy Center of the University of Central Florida, Cocoa, FL); Davis, Kristopher (Florida Solar Energy Center of the University of Central Florida, Cocoa, FL); Reedy, Robert (Florida Solar Energy Center of the University of Central Florida, Cocoa, FL); Kuszmaul, Scott S.; Sena-Henderson, Lisa; David, Carolyn; Akhil, Abbas Ali

    2012-03-01

    Initiated in 2008, the Solar Energy Grid Integration Systems (SEGIS) program is a partnership involving the U.S. DOE, Sandia National Laboratories, private sector companies, electric utilities, and universities. Projects supported under the program have focused on the complete-system development of solar technologies, with the dual goal of expanding utility-scale penetration and addressing new challenges of connecting large-scale solar installations in higher penetrations to the electric grid. The Florida Solar Energy Center (FSEC), its partners, and Sandia National Laboratories have successfully collaborated to complete the work under the third and final stage of the SEGIS initiative. The SEGIS program was a three-year, three-stage project that include conceptual design and market analysis in Stage 1, prototype development and testing in Stage 2, and moving toward commercialization in Stage 3. Under this program, the FSEC SEGIS team developed a comprehensive vision that has guided technology development that sets one methodology for merging photovoltaic (PV) and smart-grid technologies. The FSEC team's objective in the SEGIS project is to remove barriers to large-scale general integration of PV and to enhance the value proposition of photovoltaic energy by enabling PV to act as much as possible as if it were at the very least equivalent to a conventional utility power plant. It was immediately apparent that the advanced power electronics of these advanced inverters will go far beyond conventional power plants, making high penetrations of PV not just acceptable, but desirable. This report summarizes a three-year effort to develop, validate and commercialize Grid-Smart Inverters for wider photovoltaic utilization, particularly in the utility sector.

  3. Non-linear absorption for concentrated solar energy transport

    Energy Technology Data Exchange (ETDEWEB)

    Jaramillo, O. A; Del Rio, J.A; Huelsz, G [Centro de Investigacion de Energia, UNAM, Temixco, Morelos (Mexico)

    2000-07-01

    In order to determine the maximum solar energy that can be transported using SiO{sub 2} optical fibers, analysis of non-linear absorption is required. In this work, we model the interaction between solar radiation and the SiO{sub 2} optical fiber core to determine the dependence of the absorption of the radioactive intensity. Using Maxwell's equations we obtain the relation between the refractive index and the electric susceptibility up to second order in terms of the electric field intensity. This is not enough to obtain an explicit expression for the non-linear absorption. Thus, to obtain the non-linear optical response, we develop a microscopic model of an harmonic driven oscillators with damp ing, based on the Drude-Lorentz theory. We solve this model using experimental information for the SiO{sub 2} optical fiber, and we determine the frequency-dependence of the non-linear absorption and the non-linear extinction of SiO{sub 2} optical fibers. Our results estimate that the average value over the solar spectrum for the non-linear extinction coefficient for SiO{sub 2} is k{sub 2}=10{sup -}29m{sup 2}V{sup -}2. With this result we conclude that the non-linear part of the absorption coefficient of SiO{sub 2} optical fibers during the transport of concentrated solar energy achieved by a circular concentrator is negligible, and therefore the use of optical fibers for solar applications is an actual option. [Spanish] Con el objeto de determinar la maxima energia solar que puede transportarse usando fibras opticas de SiO{sub 2} se requiere el analisis de absorcion no linear. En este trabajo modelamos la interaccion entre la radiacion solar y el nucleo de la fibra optica de SiO{sub 2} para determinar la dependencia de la absorcion de la intensidad radioactiva. Mediante el uso de las ecuaciones de Maxwell obtenemos la relacion entre el indice de refraccion y la susceptibilidad electrica hasta el segundo orden en terminos de intensidad del campo electrico. Esto no es

  4. Diurnal Solar Energy Conversion and Photoprotection in Rice Canopies.

    Science.gov (United States)

    Meacham, Katherine; Sirault, Xavier; Quick, W Paul; von Caemmerer, Susanne; Furbank, Robert

    2017-01-01

    Genetic improvement of photosynthetic performance of cereal crops and increasing the efficiency with which solar radiation is converted into biomass has recently become a major focus for crop physiologists and breeders. The pulse amplitude modulated chlorophyll fluorescence technique (PAM) allows quantitative leaf level monitoring of the utilization of energy for photochemical light conversion and photoprotection in natural environments, potentially over the entire crop lifecycle. Here, the diurnal relationship between electron transport rate (ETR) and irradiance was measured in five cultivars of rice (Oryza sativa) in canopy conditions with PAM fluorescence under natural solar radiation. This relationship differed substantially from that observed for conventional short term light response curves measured under controlled actinic light with the same leaves. This difference was characterized by a reduced curvature factor when curve fitting was used to model this diurnal response. The engagement of photoprotective processes in chloroplast electron transport in leaves under canopy solar radiation was shown to be a major contributor to this difference. Genotypic variation in the irradiance at which energy flux into photoprotective dissipation became greater than ETR was observed. Cultivars capable of higher ETR at midrange light intensities were shown to produce greater leaf area over time, estimated by noninvasive imaging.

  5. Implications of solar wind measurements for solar models and composition

    Science.gov (United States)

    Serenelli, Aldo; Scott, Pat; Villante, Francesco L.; Vincent, Aaron C.; Asplund, Martin; Basu, Sarbani; Grevesse, Nicolas; Peña-Garay, Carlos

    2016-11-01

    We critically examine recent claims of a high solar metallicity by von Steiger & Zurbuchen (2016, vSZ16) based on in situ measurements of the solar wind, rather than the standard spectroscopically inferred abundances (Asplund et al. 2009, hereafter AGSS09). We test the claim by Vagnozzi et al. (2016) that a composition based on the solar wind enables one to construct a standard solar model in agreement with helioseismological observations and thus solve the decades-old solar modelling problem. We show that, although some helioseismological observables are improved compared to models computed with spectroscopic abundances, most are in fact worse. The high abundance of refractory elements leads to an overproduction of neutrinos, with a predicted 8B flux that is nearly twice its observed value, and 7Be and CNO fluxes that are experimentally ruled out at high confidence. A combined likelihood analysis shows that models using the vSZ16 abundances are worse than AGSS09 despite a higher metallicity. We also present astrophysical and spectroscopic arguments showing the vSZ16 composition to be an implausible representation of the solar interior, identifying the first ionization potential effect in the outer solar atmosphere and wind as the likely culprit.

  6. Schools Going Solar: A Guide to Schools Enjoying the Power of Solar Energy.

    Science.gov (United States)

    Gibson, Bob; Mayotte, Jenna; Cochran, Jacquie

    Schools today are hosting the solar energy systems that will become commonplace tomorrow in public buildings, homes, and businesses. This publication serves as a guide to how schools are using solar energy, listing scores of schools currently using the sun for lighting, heating, and cooling as well as highlights of innovative programs to expand…

  7. Deterministically Driven Avalanche Models of Solar Flares

    CERN Document Server

    Strugarek, Antoine; Joseph, Richard; Pirot, Dorian

    2014-01-01

    We develop and discuss the properties of a new class of lattice-based avalanche models of solar flares. These models are readily amenable to a relatively unambiguous physical interpretation in terms of slow twisting of a coronal loop. They share similarities with other avalanche models, such as the classical stick--slip self-organized critical model of earthquakes, in that they are driven globally by a fully deterministic energy loading process. The model design leads to a systematic deficit of small scale avalanches. In some portions of model space, mid-size and large avalanching behavior is scale-free, being characterized by event size distributions that have the form of power-laws with index values, which, in some parameter regimes, compare favorably to those inferred from solar EUV and X-ray flare data. For models using conservative or near-conservative redistribution rules, a population of large, quasiperiodic avalanches can also appear. Although without direct counterparts in the observational global st...

  8. SOLAR ENERGY PROGRAM: CHAPTER FROM THE ENERGY AND ENVIRONMENT ANNUAL REPORT 1979

    Energy Technology Data Exchange (ETDEWEB)

    Authors, Various

    1980-10-01

    Solar energy has become a major alternative for supplying a substantial fraction of the nation's future energy needs. The Department of Energy (DOE) supports activities ranging from the demonstration of existing technology to research on future possibilities; and at LBL projects are in progress which span that range of activities. To assess various solar applications it is important to quantify the solar resource. In one project, LBL is cooperating with the Pacific Gas and Electric Company in the implementation and operation of a solar radiation data collection network in northern California. Special instruments have been developed and are now in use to measure the solar and circumsolar (around the sun) radiation. These measurements serve to predict the performance of solar designs which use focusing collectors (mirrors or lenses) to concentrate the sunlight. Efforts are being made to assist DOE in demonstrating existing solar technology. DOE's San Francisco Operations Office (SAN) has been given technical support for its management of commercial-building solar demonstration projects. The installation of a solar hot water and space heating system on an LBL building established model techniques and procedures as part of the DOE Facilities Solar Demonstration Program. Technical support is also provided for SAN in a DOE small scale technology pilot program in which grants are awarded to individuals and organizations to develop and demonstrate solar technologies appropriate to small scale use. In the near future it is expected that research will exert a substantial impact in the areas of solar heating and cooling. An absorption air conditioner is being developed that is air cooled yet suitable for use with temperatures available from flat plate collectors. With inexpensive but sophisticated micro-electronics to control their operation, the performance of many-component solar heating and cooling systems may be improved, and work is under way to develop such a

  9. DETAILED MODELLING OF CHARGING BEHAVIOUR OF SMART SOLAR TANKS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Andersen, Elsa; Furbo, Simon

    2010-01-01

    The charging behaviour of smart solar tanks for solar combisystems for one-family houses is investigated with detailed Computational Fluid Dynamics (CFD) modelling and Particle Image Velocimetry (PIV) measurements. The smart solar tank can be charged with a variable auxiliary volume fitted...... to the expected future energy demand. Therefore the heat loss from the tank is decreased and the thermal performance of the solar heating system is increased compared to a traditional system with a fixed auxiliary volume. The solar tank can be charged either by an electric heating element situated in the tank...... or by an electric heating element in a side-arm mounted on the side of the tank. Detailed CFD models of the smart tanks are built with different mesh densities in the tank and in the side-arm. The thermal conditions of the tank during charging are calculated with the CFD models. The fluid flow and temperature...

  10. DETAILED MODELLING OF CHARGING BEHAVIOUR OF SMART SOLAR TANKS

    DEFF Research Database (Denmark)

    Fan, Jianhua; Andersen, Elsa; Furbo, Simon

    The charging behaviour of smart solar tanks for solar combisystems for one-family houses is investigated with detailed Computational Fluid Dynamics (CFD) modelling and Particle Image Velocimetry (PIV) measurements. The smart solar tank can be charged with a variable auxiliary volume fitted...... to the expected future energy demand. Therefore the heat loss from the tank is decreased and the thermal performance of the solar heating system is increased compared to a traditional system with a fixed auxiliary volume. The solar tank can be charged either by an electric heating element situated in the tank...... or by an electric heating element in a side-arm mounted on the side of the tank. Detailed CFD models of the smart tanks are built with different mesh densities in the tank and in the side-arm. The thermal conditions of the tank during charging are calculated with the CFD models. The fluid flow and temperature...

  11. Heat transfer and flow in solar energy and bioenergy systems

    Science.gov (United States)

    Xu, Ben

    The demand for clean and environmentally benign energy resources has been a great concern in the last two decades. To alleviate the associated environmental problems, reduction of the use of fossil fuels by developing more cost-effective renewable energy technologies becomes more and more significant. Among various types of renewable energy sources, solar energy and bioenergy take a great proportion. This dissertation focuses on the heat transfer and flow in solar energy and bioenergy systems, specifically for Thermal Energy Storage (TES) systems in Concentrated Solar Power (CSP) plants and open-channel algal culture raceways for biofuel production. The first part of this dissertation is the discussion about mathematical modeling, numerical simulation and experimental investigation of solar TES system. First of all, in order to accurately and efficiently simulate the conjugate heat transfer between Heat Transfer Fluid (HTF) and filler material in four different solid-fluid TES configurations, formulas of an e?ective heat transfer coe?cient were theoretically developed and presented by extending the validity of Lumped Capacitance Method (LCM) to large Biot number, as well as verifications/validations to this simplified model. Secondly, to provide design guidelines for TES system in CSP plant using Phase Change Materials (PCM), a general storage tank volume sizing strategy and an energy storage startup strategy were proposed using the enthalpy-based 1D transient model. Then experimental investigations were conducted to explore a novel thermal storage material. The thermal storage performances were also compared between this novel storage material and concrete at a temperature range from 400 °C to 500 °C. It is recommended to apply this novel thermal storage material to replace concrete at high operating temperatures in sensible heat TES systems. The second part of this dissertation mainly focuses on the numerical and experimental study of an open-channel algae

  12. 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.

  13. 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)

  14. 76 FR 78021 - Notice of Availability of the Record of Decision for the Rice Solar Energy, LLC, Rice Solar...

    Science.gov (United States)

    2011-12-15

    ... Bureau of Land Management Notice of Availability of the Record of Decision for the Rice Solar Energy, LLC, Rice Solar Energy Project (RSEP) and California Desert Conservation Area Plan Amendment, California...: Rice Solar Energy, LLC, a subsidiary of SolarReserve, LLC plans to construct a 150 megawatt (MW)...

  15. Cost Effective System Modeling of Active Micro- Module Solar Tracker

    Directory of Open Access Journals (Sweden)

    Md. Faisal Shuvo

    2014-01-01

    Full Text Available The increasing interests in using renewable energies are coming from solar thermal energy and solar photovoltaic systems to the micro production of electricity. Usually we already have considered the solar tracking topology in large scale applications like power plants and satellite but most of small scale applications don’t have any solar tracker system, mainly because of its high cost and complex circuit design. From that aspect, this paper confab microcontroller based one dimensional active micro-module solar tracking system, in which inexpensive LDR is used to generate reference voltage to operate microcontroller for functioning the tracking system. This system provides a fast response of tracking system to the parameters like change of light intensity as well as temperature variations. This micro-module model of tracking system can be used for small scale applications like portable electronic devices and running vehicles.

  16. Very Short-term Nonparametric Probabilistic Forecasting of Renewable Energy Generation - with Application to Solar Energy

    DEFF Research Database (Denmark)

    Golestaneh, Faranak; Pinson, Pierre; Gooi, Hoay Beng

    2016-01-01

    Due to the inherent uncertainty involved in renewable energy forecasting, uncertainty quantification is a key input to maintain acceptable levels of reliability and profitability in power system operation. A proposal is formulated and evaluated here for the case of solar power generation, when only...... approach to generate very short-term predictive densities, i.e., for lead times between a few minutes to one hour ahead, with fast frequency updates. We rely on an Extreme Learning Machine (ELM) as a fast regression model, trained in varied ways to obtain both point and quantile forecasts of solar power...... generation. Four probabilistic methods are implemented as benchmarks. Rival approaches are evaluated based on a number of test cases for two solar power generation sites in different climatic regions, allowing us to show that our approach results in generation of skilful and reliable probabilistic forecasts...

  17. GLOBAL IMPACT OF SOLAR ENERGY, CASE STUDY - GERMANY

    Directory of Open Access Journals (Sweden)

    Gheorghe Caralicea Marculescu

    2014-02-01

    Full Text Available Renewable energy is a socially and politically defined category of energy sources. Renewable energy is generally defined as energy that comes from resources which are continually replenished on a human timescale such as sunlight, wind, rain, tides, waves and geothermal heat. About 16% of global final energy consumption comes from renewable resources, with 10% of all energy from traditional biomass, mainly used for heating, and 3.4% from hydroelectricity. New renewables (small hydro, modern biomass, wind, solar, geothermal, and biofuels accounted for another 3% and are growing rapidly. This paper seeks is aimed at presenting the impact solar energy could have on a world level given the finitude, reachability and ever increasing prices of fossil fuels. As a case study we will present the solar energy industry in Germany emphasizing the advantages and disadvantages this form of energy has in this country and worldwide.

  18. 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.

  19. Photoswitchable Molecular Rings for Solar-Thermal Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Durgun, E; Grossman, JC

    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.

  20. 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.