WorldWideScience

Sample records for polarizations solar power

  1. Space Solar Power Technology Demonstration for Lunar Polar Applications: Laser-Photovoltaic Wireless Power Transmission

    Science.gov (United States)

    Henley, M. W.; Fikes, J. C.; Howell, J.; Mankins, J. C.; Howell, Joe T. (Technical Monitor)

    2002-01-01

    Space Solar Power technology offers unique benefits for near-term NASA space science missions, which can mature this technology for other future applications. "Laser-Photo-Voltaic Wireless Power Transmission" (Laser-PV WPT) is a technology that uses a laser to beam power to a photovoltaic receiver, which converts the laser's light into electricity. Future Laser-PV WPT systems may beam power from Earth to satellites or large Space Solar Power satellites may beam power to Earth, perhaps supplementing terrestrial solar photo-voltaic receivers. In a near-term scientific mission to the moon, Laser-PV WPT can enable robotic operations in permanently shadowed lunar polar craters, which may contain ice. Ground-based technology demonstrations are proceeding, to mature the technology for this initial application, in the moon's polar regions.

  2. Solar Power

    Science.gov (United States)

    Ford, Norman C.; Kane, Joseph W.

    1971-01-01

    Proposes a method of collecting solar energy by using available plastics for Fresnel lenses to focus heat onto a converter where thermal dissociation of water would produce hydrogen. The hydrogen would be used as an efficient non-polluting fuel. Cost estimates are included. (AL)

  3. Solar Power Grid

    Science.gov (United States)

    2008-01-01

    Shown here is one of the first images taken by NASA's Phoenix Mars Lander of one of the octagonal solar panels, which opened like two handheld, collapsible fans on either side of the spacecraft. Beyond this view is a small slice of the north polar terrain of Mars. The successfully deployed solar panels are critical to the success of the 90-day mission, as they are the spacecraft's only means of replenishing its power. Even before these images reached Earth, power readings from the spacecraft indicated to engineers that the solar panels were already at work recharging the spacecraft's batteries. Before deploying the Surface Stereo Imager to take these images, the lander waited about 15 minutes for the dust to settle. This image was taken by the spacecraft's Surface Stereo Imager on Sol, or Martian day, 0 (May 25, 2008). The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  4. Solar Power Grid Unfurled

    Science.gov (United States)

    2008-01-01

    Shown here is one of the first images taken by NASA's Phoenix Mars Lander of one of the octagonal solar panels, which opened like two handheld, collapsible fans on either side of the spacecraft. Beyond this view is a small slice of the north polar terrain of Mars. The successfully deployed solar panels are critical to the success of the 90-day mission, as they are the spacecraft's only means of replenishing its power. Even before these images reached Earth, power readings from the spacecraft indicated to engineers that the solar panels were already at work recharging the spacecraft's batteries. Before deploying the Surface Stereo Imager to take these images, the lander waited about 15 minutes for the dust to settle. This image was taken by the spacecraft's Surface Stereo Imager on Sol, or Martian day, 0 (May 25, 2008). This image has been geometrically corrected. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  5. Solar power roof shingle

    Science.gov (United States)

    Forestieri, A. F.; Ratajczak, A. F.; Sidorak, L. G.

    1975-01-01

    Silicon solar cell module provides both all-weather protection and electrical power. Module consists of array of circular silicon solar cells bonded to fiberglass substrate roof shingle with fluorinated ethylene propylene encapsulant.

  6. Solar thermal power plants

    International Nuclear Information System (INIS)

    Schnatbaum, L.

    2009-01-01

    The solar thermal power plant technology, the opportunities it presents and the developments in the market are outlined. The focus is on the technology of parabolic trough power plants, a proven technology for solar power generation on a large scale. In a parabolic trough power plant, trough-shaped mirrors concentrate the solar irradiation onto a pipe in the focal line of the collector. The thermal energy thus generated is used for electricity generation in a steam turbine. Parabolic trough plants can be combined with thermal storage and fossil or biomass fired heat exchangers to generate electricity even when the sun is not shining. Solar Millennium AG in Erlangen has developed the first power plant of this kind in Europe. After two years of construction the plant started operation in Southern Spain in 2008. This one and its sister projects are important steps leading the way for the whole market. The paper also covers the technological challenges, the key components used and the research and development activities concerning this technology. Solar thermal power plants are ideal for covering peak and medium loads in power grids. In hybrid operation they can also cover base-load. The Solar Chimney power plant, another striking technology for the conversion of solar into electric energy, is described briefly. The paper concludes with a look at the future - the import of solar energy from the deserts of North Africa to central Europe. (author)

  7. Can solar power deliver?

    Science.gov (United States)

    Nelson, Jenny; Emmott, Christopher J M

    2013-08-13

    Solar power represents a vast resource which could, in principle, meet the world's needs for clean power generation. Recent growth in the use of photovoltaic (PV) technology has demonstrated the potential of solar power to deliver on a large scale. Whilst the dominant PV technology is based on crystalline silicon, a wide variety of alternative PV materials and device concepts have been explored in an attempt to decrease the cost of the photovoltaic electricity. This article explores the potential for such emerging technologies to deliver cost reductions, scalability of manufacture, rapid carbon mitigation and new science in order to accelerate the uptake of solar power technologies.

  8. Concentrated solar power generation using solar receivers

    Science.gov (United States)

    Anderson, Bruce N.; Treece, William Dean; Brown, Dan; Bennhold, Florian; Hilgert, Christoph

    2017-08-08

    Inventive concentrated solar power systems using solar receivers, and related devices and methods, are generally described. Low pressure solar receivers are provided that function to convert solar radiation energy to thermal energy of a working fluid, e.g., a working fluid of a power generation or thermal storage system. In some embodiments, low pressure solar receivers are provided herein that are useful in conjunction with gas turbine based power generation systems.

  9. Pioneering with Solar Power.

    Science.gov (United States)

    Pollack, George; Pollack, Mary

    1982-01-01

    Describes the development of Mississippi County Community College's (MCCC's) solar energy system. Explains the functioning of the campus's computer-controlled photovoltaic concentrator system, MCCC's cooperative agreement with the Arkansas-Missouri Power Company, program funding, the integration of the solar system with other building components,…

  10. Solar powered dugout aeration

    International Nuclear Information System (INIS)

    Murrell, S.

    2001-10-01

    Pasture dugouts are a significant source of water for livestock on the Canadian Prairies and as such, must maintain the best water quality possible. Aeration improves the water quality and is part of a good management plan to reduce overall water treatment costs. Although dugouts can be aerated naturally through wind and wave action and photosynthesis, this generally aerates only the top portion of the dugout. Artificial aeration by air injection into the lowest point of the dugout ensures that the water is oxygenated throughout the entire dugout. Solar aeration can be used in remote areas where grid power is not practical. With solar powered aeration systems, solar panels are used to generate the electrical power needed to run the compressor while storing excess energy in batteries. A solar aeration system includes solar panels, deep cycle batteries to store excess power, a control board with a regulator, a compressor, a weighed feeder hose, and an air diffuser. This publication presented the design of a solar aeration system and its cost. 1 tab., 3 figs

  11. Concentrating Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    Weinstein, Lee A.; Loomis, James; Bhatia, Bikram; Bierman, David M.; Wang, Evelyn N.; Chen, Gang

    2015-12-09

    Solar energy is a bountiful renewable energy resource: the energy in the sunlight that reaches Earth in an hour exceeds the energy consumed by all of humanity in a year.(1) While the phrase “solar energy conversion” probably brings photovoltaic (PV) cells to mind first, PV is not the only option for generating electricity from sunlight. Another promising technology for solar energy conversion is solar–thermal conversion, commonly referred to as concentrating solar power (CSP).(2) The first utility-scale CSP plants were constructed in the 1980s, but in the two decades that followed, CSP saw little expansion.(3, 4) More recent years, however, have seen a CSP renaissance due to unprecedented growth in the adoption of CSP.(3, 5) Photographs of two operating CSP plants, a parabolic trough collector plant and a central receiver (or “power tower”), are shown here.

  12. Solar powered Stirling engine

    Energy Technology Data Exchange (ETDEWEB)

    Meijer, R.J.

    1987-11-24

    In a solar dish module which comprises a dish which receives incident solar rays and reflects them to a focus at which is located the combination of a receiver and a heat engine organized and arranged so that the heat energy of the reflected solar rays collected at the receiver powers the engine, and wherein the receiver and heat engine are supported from the dish by a framework, the improvement is described which comprises journal means for journaling at least the engine on the framework to maintain certain predetermined spatial orientation for the engine in relation to the direction of gravity irrespective of spatial orientation of the dish.

  13. Solar Powered Refrigeration System

    Science.gov (United States)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2002-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  14. Solar Thermal Power.

    Science.gov (United States)

    McDaniels, David K.

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

  15. Solar Sea Power

    Science.gov (United States)

    Zener, Clarence

    1976-01-01

    In their preoccupation with highly complex new energy systems, scientists and statesmen may be overlooking the possibilities of Ocean Thermal Energy Conversion (OTEC). That is the view of a Carnegie-Mellon University physicist who is in the forefront of solar sea power investigation. (Author/BT)

  16. Solar Illumination Control of the Polar Wind

    Science.gov (United States)

    Maes, L.; Maggiolo, R.; De Keyser, J.; André, M.; Eriksson, A. I.; Haaland, S.; Li, K.; Poedts, S.

    2017-11-01

    Polar wind outflow is an important process through which the ionosphere supplies plasma to the magnetosphere. The main source of energy driving the polar wind is solar illumination of the ionosphere. As a result, many studies have found a relation between polar wind flux densities and solar EUV intensity, but less is known about their relation to the solar zenith angle at the ionospheric origin, certainly at higher altitudes. The low energy of the outflowing particles and spacecraft charging means it is very difficult to measure the polar wind at high altitudes. We take advantage of an alternative method that allows estimations of the polar wind flux densities far in the lobes. We analyze measurements made by the Cluster spacecraft at altitudes from 4 up to 20 RE. We observe a strong dependence on the solar zenith angle in the ion flux density and see that both the ion velocity and density exhibit a solar zenith angle dependence as well. We also find a seasonal variation of the flux density.

  17. Concentrating solar thermal power.

    Science.gov (United States)

    Müller-Steinhagen, Hans

    2013-08-13

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

  18. Solar Power Sources: PV, Concentrated PV, and Concentrated Solar Power

    DEFF Research Database (Denmark)

    Kim, Katherine A.; Mentesidi, Konstantina; Yang, Yongheng

    2017-01-01

    Solar power is highly abundant, relatively reliable, and not limited to a geographic region, making it one of the most important renewable energy sources. Catering for a clean and green energy system, solar energy will be an active player in the future mixed power grid that is also undergoing...... a significant change. Beyond this energy transition, the still declining cost of the solar technology has become an important driving force for more solar-powered systems. However, high penetration of solar-powered systems also brings technical challenges to the entire energy systems. In order to fully address...... those issues, the technological properties of solar power should be investigated. Thus, the basics of solar power technology will be introduced and discussed in this chapter....

  19. Solar Power Sources: PV, Concentrated PV, and Concentrated Solar Power

    DEFF Research Database (Denmark)

    Kim, Katherine A.; Mentesidi, Konstantina; Yang, Yongheng

    2017-01-01

    a significant change. Beyond this energy transition, the still declining cost of the solar technology has become an important driving force for more solar-powered systems. However, high penetration of solar-powered systems also brings technical challenges to the entire energy systems. In order to fully address......Solar power is highly abundant, relatively reliable, and not limited to a geographic region, making it one of the most important renewable energy sources. Catering for a clean and green energy system, solar energy will be an active player in the future mixed power grid that is also undergoing...... those issues, the technological properties of solar power should be investigated. Thus, the basics of solar power technology will be introduced and discussed in this chapter....

  20. Scattering Polarization in Solar Flares

    Czech Academy of Sciences Publication Activity Database

    Štěpán, Jiří; Heinzel, Petr

    2013-01-01

    Roč. 778, č. 1 (2013), L6/1-L6/6 ISSN 2041-8205 R&D Projects: GA ČR GAP209/12/1652; GA ČR GPP209/12/P741 Institutional support: RVO:67985815 Keywords : line formation * polarization * radiative transfer Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 5.602, year: 2013

  1. Solar thermal power system

    Science.gov (United States)

    Bennett, Charles L.

    2010-06-15

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

  2. Solar Power Satellites

    CERN Document Server

    Flournoy, Don M

    2012-01-01

    Communication satellites are a $144 billion industry. Is there any space-based industry that could possibly beat that market? 'Solar Power Satellites' shows why and how the space satellite industry will soon begin expanding its market from relaying signals to Earth to generating energy in space and delivering it to the ground as electricity. In all industrialized nations, energy demand is growing exponentially. In the developing world, the need for energy is as basic as food and water. The Sun's energy is available everywhere, and it is non-polluting. As business plans demonstrate its technical feasibility, commercial potential, and environmental acceptability, every country on Earth will look to space for the power it needs.

  3. Decentralised Solar Power at Homes

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Decentralised Solar Power at Homes. Solar PV gives DC Power. But load is AC; Needs a DC-AC convertor. Now if we add a battery. Battery stores only DC. Require a AC-DC convertor for charging; Require a DC-AC convertor during discharging. For low power, each ...

  4. Concentrated solar power: an overview

    International Nuclear Information System (INIS)

    Najam, Z.; Khan, M.I.

    2011-01-01

    Solar thermal power is a relatively new technology and a fine arrangement for the provision of Electrical Energy and Clean Energy in general .The concentrated solar offers a viable option for the Sunny Zones of the world. The efficiency of the System depends on a few factors like Area, Intensity of Sunlight, Type of receiver, Hybridisation etc. Solar Thermal Systems employ lenses or mirrors to focus a large area of sunlight onto a small area. Electrical power is produced when the concentrated light is impugned onto photovoltaic cell made surfaces or used to heat a transfer fluid for a conventional power plant. In this paper we give a brief overview of a baseline Solar Thermal Power Plant, Technological details, Cost and Benefit analysis, a glimpse of solar thermal power and future of solar thermal power. (author)

  5. Lunar solar-power system: Commerical power

    Science.gov (United States)

    Criswell, David R.

    1995-01-01

    The proposed Lunar Solar-Power (LSP) System collects solar power on the moon. The power is converted to beams of microwaves and transmitted to fields of microwave receivers (rectennas) on Earth that provide electric power to local and regional power grids. LSP can provide abundant and low cost energy to Earth to sustain several centuries of economic development on Earth and in space. The LSP power is independent of the biosphere (global warming, weather, and climate changes), independent of reserves of terrestrial non-renewable and renewable power, and is low in total costs compared to other large scale power systems. Efficient utilization of the moon as a platform for solar collectors/power transmitters and as a source of building materials is key to the development and emplacement of the LSP System. LSP development costs can be significantly reduced by the establishment of a manned lunar base.

  6. Concentration solar thermal power

    International Nuclear Information System (INIS)

    Livet, F.

    2011-01-01

    As the production of electricity by concentration solar power (CSP) installations is said to be a source of energy for the future, the author discusses past experiments (notably the French Thermis project), and the different techniques which are currently being used. He indicates the regions which appear to be the most appropriate for this technique. He presents the three main techniques: parabolic cylinder, tower, and Stirling cycle installations. He discusses the issue of intermittency. He proposes an assessment of prices and of their evolution, and indicates the investments made in different installations (in Italy, Spain, Germany and Portugal). He comments the case of hybrid installations (sun and gas), evokes the Desertec project proposed by the German industry which comprises a set of hybrid installations. He notices that there is no significant technological evolution for this process

  7. Financing Solar Thermal Power Plants

    International Nuclear Information System (INIS)

    Price, Henry W.; Kistner, Rainer

    1999-01-01

    The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been build following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply stated, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised in debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects from the financier's perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies

  8. Financing solar thermal power plants

    International Nuclear Information System (INIS)

    Kistner, R.; Price, H.

    1999-01-01

    The commercialization of concentrating solar power technology took a major step forward in the mid 1980s and early 1990s with the development of the SEGS plants in California. Over the years they have proven that parabolic trough power technologies are the most cost-effective approach for commercial scale solar power generation in the sunbelt countries of the world. However, the question must be asked why no additional solar power plants have been built following the bankruptcy of the developer of the SEGS projects, LUZ International Limited. Although many believe the SEGS projects were a success as a result of parabolic trough technology they employ, in truth, the SEGS projects were developed simply because they represented an attractive opportunity for investors. Simply states, no additional projects have been developed because no one has been able to put together a similarly attractive financial package to potential investors. More than $1.2 billion in private capital was raised in debt and equity financing for the nine SEGS plants. Investors and bankers who make these investments are the real clients for solar power technologies. They are not interested in annual solar to electric efficiencies, but in risk, return on investments, and coverage ratios. This paper will take a look at solar power projects form the financier's perspective. The challenge in moving forward is to attract private investors, commercial lenders, and international development agencies and to find innovative solutions to the difficult issues that investment in the global power market poses for solar power technologies

  9. Variations in Solar Parameters and Cosmic Rays with Solar Magnetic Polarity

    Energy Technology Data Exchange (ETDEWEB)

    Oh, S. [Department of Earth Science Education, Chonnam National University, Gwangju, 61186 (Korea, Republic of); Yi, Y., E-mail: suyeonoh@jnu.ac.kr [Department of Astronomy, Space Science and Geology, Chungnam National University, Daejeon, 34134 (Korea, Republic of)

    2017-05-01

    The sunspot number varies with the 11-year Schwabe cycle, and the solar magnetic polarity reverses every 11 years approximately at the solar maximum. Because of polarity reversal, the difference between odd and even solar cycles is seen in solar activity. In this study, we create the mean solar cycle expressed by phase using the monthly sunspot number for all solar cycles 1–23. We also generate the mean solar cycle for sunspot area, solar radio flux, and cosmic ray flux within the allowance of observational range. The mean solar cycle has one large peak at solar maximum for odd solar cycles and two small peaks for most even solar cycles. The odd and even solar cycles have the statistical difference in value and shape at a confidence level of at least 98%. For solar cycles 19–23, the second peak in the even solar cycle is larger than the first peak. This result is consistent with the frequent solar events during the declining phase after the solar maximum. The difference between odd and even solar cycles can be explained by a combined model of polarity reversal and solar rotation. In the positive/negative polarity, the polar magnetic field introduces angular momentum in the same/opposite direction as/to the solar rotation. Thus the addition/subtraction of angular momentum can increase/decrease the motion of plasma to support the formation of sunspots. Since the polarity reverses at the solar maximum, the opposite phenomenon occurs in the declining phase.

  10. CHROMOSPHERIC POLARIZATION IN THE PHOTOSPHERIC SOLAR OXYGEN INFRARED TRIPLET

    Energy Technology Data Exchange (ETDEWEB)

    Del Pino Alemán, Tanausú; Trujillo Bueno, Javier [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2015-07-20

    We present multilevel radiative transfer modeling of the scattering polarization observed in the solar O i infrared triplet around 777 nm. We demonstrate that the scattering polarization pattern observed on the solar disk forms in the chromosphere, far above the photospheric region where the bulk of the emergent intensity profiles originate. We investigate the sensitivity of the polarization pattern to the thermal structure of the solar atmosphere and to the presence of weak magnetic fields (10{sup −2}–100 G) through the Hanle effect, showing that the scattering polarization signals of the oxygen infrared triplet encode information on the magnetism of the solar chromosphere.

  11. Solar dynamic power systems for space station

    Science.gov (United States)

    Irvine, Thomas B.; Nall, Marsha M.; Seidel, Robert C.

    1986-01-01

    The Parabolic Offset Linearly Actuated Reflector (POLAR) solar dynamic module was selected as the baseline design for a solar dynamic power system aboard the space station. The POLAR concept was chosen over other candidate designs after extensive trade studies. The primary advantages of the POLAR concept are the low mass moment of inertia of the module about the transverse boom and the compactness of the stowed module which enables packaging of two complete modules in the Shuttle orbiter payload bay. The fine pointing control system required for the solar dynamic module has been studied and initial results indicate that if disturbances from the station are allowed to back drive the rotary alpha joint, pointing errors caused by transient loads on the space station can be minimized. This would allow pointing controls to operate in bandwidths near system structural frequencies. The incorporation of the fine pointing control system into the solar dynamic module is fairly straightforward for the three strut concentrator support structure. However, results of structural analyses indicate that this three strut support is not optimum. Incorporation of a vernier pointing system into the proposed six strut support structure is being studied.

  12. Concentrated solar thermal power - Now

    Energy Technology Data Exchange (ETDEWEB)

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

    2005-09-15

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

  13. Alfvénic fluctuations in "newborn"' polar solar wind

    Directory of Open Access Journals (Sweden)

    B. Bavassano

    2005-06-01

    Full Text Available The 3-D structure of the solar wind is strongly dependent upon the Sun's activity cycle. At low solar activity a bimodal structure is dominant, with a fast and uniform flow at the high latitudes, and slow and variable flows at low latitudes. Around solar maximum, in sharp contrast, variable flows are observed at all latitudes. This last kind of pattern, however, is a relatively short-lived feature, and quite soon after solar maximum the polar wind tends to regain its role. The plasma parameter distributions for these newborn polar flows appear very similar to those typically observed in polar wind at low solar activity. The point addressed here is about polar wind fluctuations. As is well known, the low-solar-activity polar wind is characterized by a strong flow of Alfvénic fluctuations. Does this hold for the new polar flows too? An answer to this question is given here through a comparative statistical analysis on parameters such as total energy, cross helicity, and residual energy, that are of general use to describe the Alfvénic character of fluctuations. Our results indicate that the main features of the Alfvénic fluctuations observed in low-solar-activity polar wind have been quickly recovered in the new polar flows developed shortly after solar maximum. Keywords. Interplanetary physics (MHD waves and turbulence; Sources of the solar wind – Space plasma physics (Turbulence

  14. Solar thermal and concentrated solar power barometer

    International Nuclear Information System (INIS)

    2013-01-01

    The European concentrated solar power plant market is steeling itself for tough time ahead. The number of projects under construction is a pittance compared with 2012 that was an excellent year for installations (an additional 802.5 MW of capacity recorded). This drop is the result of the moratorium on renewable energy power plants introduced by the Spanish government. The European solar thermal market is hardly any more encouraging . EurObserv'ER holds that it slipped for the fourth year in a row (it dropped 5.5% between 2011 and 2012). The newly-installed solar thermal collector surface area in the EU now stands at 3.4 million m 2 , far short of its 2008 installation record of 4.6 million m 2 . The EU's solar thermal base to date at the end of 2012 is 29.6 GWth with 2.4 GWth installed during the year 2012. This article gives tables gathering the figures of the production for every European country for 2012 and describes the market and the general trend for every EU member

  15. The Solar Ultraviolet Magnetograph Investigation: Polarization Properties

    Science.gov (United States)

    West, E. A.; Porter, J. G.; Davis, J. M.; Gary, G. A.; Kobayashi, K.; Noble, M.

    2005-01-01

    This paper will describe the objectives of the Marshall Space Flight Center (MSFC) Solar Ultraviolet Magnetograph Investigation (SUMI) and the optical components that have been developed to meet those objectives. A sounding rocket payload is being developed to test the feasibility of magnetic field measurements in the Sun s transition region. This paper will review the scientific measurements that will be made by the SUMI sounding rocket program, and the optics have been optimized for simultaneous measurements of two magnetic lines formed in the transition region (CIV at 1550 A and MgII at 2800 A). Finally, this paper will concentrate on the polarization properties of the SUM1 polarimeter and toroidal varied-line-space gratings.

  16. Space Solar Power: Satellite Concepts

    Science.gov (United States)

    Little, Frank E.

    1999-01-01

    Space Solar Power (SSP) applies broadly to the use of solar power for space related applications. The thrust of the NASA SSP initiative is to develop concepts and demonstrate technology for applying space solar power to NASA missions. Providing power from satellites in space via wireless transmission to a receiving station either on earth, another celestial body or a second satellite is one goal of the SSP initiative. The sandwich design is a satellite design in which the microwave transmitting array is the front face of a thin disk and the back of the disk is populated with solar cells, with the microwave electronics in between. The transmitter remains aimed at the earth in geostationary orbit while a system of mirrors directs sunlight to the photovoltaic cells, regardless of the satellite's orientation to the sun. The primary advantage of the sandwich design is it eliminates the need for a massive and complex electric power management and distribution system for the satellite. However, it requires a complex system for focusing sunlight onto the photovoltaic cells. In addition, positioning the photovoltaic array directly behind the transmitting array power conversion electronics will create a thermal management challenge. This project focused on developing designs and finding emerging technology to meet the challenges of solar tracking, a concentrating mirror system including materials and coatings, improved photovoltaic materials and thermal management.

  17. Concentrating solar power

    International Nuclear Information System (INIS)

    Metelli, Enzo; Vignolini, Mauro

    2005-01-01

    Solar energy can be used instead of fossil fuels to produce high-temperature heat for use in many industrial processes and in electricity generation. If carried out on a large scale, the replacement would make it possible to reduce harmful emissions and stabilise the global climate over the long term. ENEA has an innovative project in this sector [it

  18. Solar powered dehumidifier apparatus

    Science.gov (United States)

    Jebens, Robert W.

    1980-12-30

    A thermally insulated light transmitting housing forms a chamber containing a desiccant and having a first gas port open to the ambient and a second gas port connected by a two way valve to a volume to be dried. Solar energy transmitted through the housing heats and dries the desiccant. The increased air pressure due to the heating of the volume to be dried causes the air from the volume to be expelled through the valve into the chamber. The desiccant is then cooled by shielding it from solar energy before the volume cools thereby increasing its moisture absorbing capacity. Then the volume is allowed to cool drawing dehumidified air through the desiccant and the valve into the volume to be dried. This cycle is then repeated.

  19. Hexagon solar power panel

    Science.gov (United States)

    Rubin, I. (Inventor)

    1978-01-01

    A solar energy panel support is described upon which silicon cells are arrayed. The cells are wafer thin and of two geometrical types, both of the same area and electrical rating, namely hexagon cells and hourglass cells. The hourglass cells are composites of half hexagons. A near perfect nesting relationship of the cells achieves a high density packing whereby optimum energy production per panel area is achieved.

  20. Hexagon solar power panel

    Science.gov (United States)

    Rubin, Irwin

    1978-01-01

    A solar energy panel comprises a support upon which silicon cells are arrayed. The cells are wafer thin and of two geometrical types, both of the same area and electrical rating, namely hexagon cells and hourglass cells. The hourglass cells are composites of half hexagons. A near perfect nesting relationship of the cells achieves a high density packing whereby optimum energy production per panel area is achieved.

  1. Solar thermal power meeting - Proceedings

    International Nuclear Information System (INIS)

    2011-07-01

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

  2. Solar-Powered Refrigeration System

    Science.gov (United States)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2001-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure. and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  3. Solar-Powered Refrigeration System

    Science.gov (United States)

    Ewert, Michael K. (Inventor); Bergeron, David J., III (Inventor)

    2002-01-01

    A solar powered vapor compression refrigeration system is made practicable with thermal storage and novel control techniques. In one embodiment, the refrigeration system includes a photovoltaic panel, a variable speed compressor, an insulated enclosure, and a thermal reservoir. The photovoltaic (PV) panel converts sunlight into DC (direct current) electrical power. The DC electrical power drives a compressor that circulates refrigerant through a vapor compression refrigeration loop to extract heat from the insulated enclosure. The thermal reservoir is situated inside the insulated enclosure and includes a phase change material. As heat is extracted from the insulated enclosure, the phase change material is frozen, and thereafter is able to act as a heat sink to maintain the temperature of the insulated enclosure in the absence of sunlight. The conversion of solar power into stored thermal energy is optimized by a compressor control method that effectively maximizes the compressor's usage of available energy. A capacitor is provided to smooth the power voltage and to provide additional current during compressor start-up. A controller monitors the rate of change of the smoothed power voltage to determine if the compressor is operating below or above the available power maximum, and adjusts the compressor speed accordingly. In this manner, the compressor operation is adjusted to convert substantially all available solar power into stored thermal energy.

  4. Concentrated Solar Thermoelectric Power

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Gang [MIT; Ren, Zhifeng [University of Houston

    2015-07-09

    The goal of this project is to demonstrate in the lab that solar thermoelectric generators (STEGs) can exceed 10% solar-to-electricity efficiency, and STEGs can be integrated with phase-change materials (PCM) for thermal storage, providing operation beyond daylight hours. This project achieved significant progress in many tasks necessary to achieving the overall project goals. An accurate Themoelectric Generator (TEG) model was developed, which included realistic treatment of contact materials, contact resistances and radiative losses. In terms of fabricating physical TEGs, high performance contact materials for skutterudite TE segments were developed, along with brazing and soldering methods to assemble segmented TEGs. Accurate measurement systems for determining device performance (in addition to just TE material performance) were built for this project and used to characterize our TEGs. From the optical components’ side, a spectrally selective cermet surface was developed with high solar absorptance and low thermal emittance, with thermal stability at high temperature. A measurement technique was also developed to determine absorptance and total hemispherical emittance at high temperature, and was used to characterize the fabricated spectrally selective surfaces. In addition, a novel reflective cavity was designed to reduce radiative absorber losses and achieve high receiver efficiency at low concentration ratios. A prototype cavity demonstrated that large reductions in radiative losses were possible through this technique. For the overall concentrating STEG system, a number of devices were fabricated and tested in a custom built test platform to characterize their efficiency performance. Additionally, testing was performed with integration of PCM thermal storage, and the storage time of the lab scale system was evaluated. Our latest testing results showed a STEG efficiency of 9.6%, indicating promising potential for high performance concentrated STEGs.

  5. Solar Power System Design for the Solar Probe+ Mission

    Science.gov (United States)

    Landis, Geoffrey A.; Schmitz, Paul C.; Kinnison, James; Fraeman, Martin; Roufberg, Lew; Vernon, Steve; Wirzburger, Melissa

    2008-01-01

    Solar Probe+ is an ambitious mission proposed to the solar corona, designed to make a perihelion approach of 9 solar radii from the surface of the sun. The high temperature, high solar flux environment makes this mission a significant challenge for power system design. This paper summarizes the power system conceptual design for the solar probe mission. Power supplies considered included nuclear, solar thermoelectric generation, solar dynamic generation using Stirling engines, and solar photovoltaic generation. The solar probe mission ranges from a starting distance from the sun of 1 AU, to a minimum distance of about 9.5 solar radii, or 0.044 AU, from the center of the sun. During the mission, the solar intensity ranges from one to about 510 times AM0. This requires power systems that can operate over nearly three orders of magnitude of incident intensity.

  6. Solar Power Use Claims

    Science.gov (United States)

    The U.S. EPA's Green Power Partnership is a voluntary program designed to reduce the environmental impact of electricity generation by promoting renewable energy. EPA evaluates partnership metrics annually to determine progress toward programmatic goals.

  7. Concentrators Enhance Solar Power Systems

    Science.gov (United States)

    2013-01-01

    "Right now, solar electric propulsion is being looked at very seriously," says Michael Piszczor, chief of the photovoltaic and power technologies branch at Glen Research Center. The reason, he explains, originates with a unique NASA mission from the late 1990s. In 1998, the Deep Space 1 spacecraft launched from Kennedy Space Center to test a dozen different space technologies, including SCARLET, or the Solar Concentrator Array with Refractive Linear Element Technology. As a solar array that focused sunlight on a smaller solar cell to generate electric power, SCARLET not only powered Deep Space 1 s instruments but also powered its ion engine, which propelled the spacecraft throughout its journey. Deep Space 1 was the first spacecraft powered by a refractive concentrator design like SCARLET, and also utilized multi-junction solar cells, or cells made of multiple layers of different materials. For the duration of its 38-month mission, SCARLET performed flawlessly, even as Deep Space 1 flew by Comet Borrelly and Asteroid Braille. "Everyone remembers the ion engine on Deep Space 1, but they tend to forget that the SCARLET array powered it," says Piszczor. "Not only did both technologies work as designed, but the synergy between the two, solar power and propulsion together, is really the important aspect of this technology demonstration mission. It was the first successful use of solar electric propulsion for primary propulsion." More than a decade later, NASA is keenly interested in using solar electric propulsion (SEP) for future space missions. A key issue is cost, and SEP has the potential to substantially reduce cost compared to conventional chemical propulsion technology. "SEP allows you to use spacecraft that are smaller, lighter, and less costly," says Piszczor. "Even though it might take longer to get somewhere using SEP, if you are willing to trade time for cost and smaller vehicles, it s a good trade." Potentially, SEP could be used on future science missions

  8. Wireless Power Transmission Options for Space Solar Power

    Science.gov (United States)

    Potter, Seth; Davis, Dean; Born, Martin; Bayer, Martin; Howell, Joe; Mankins, John

    2008-01-01

    Space Solar Power (SSP), combined with Wireless Power Transmission (WPT), offers the far-term potential to solve major energy problems on Earth. In the long term, we aspire to beam energy to Earth from geostationary Earth orbit (GEO), or even further distances in space. In the near term, we can beam power over more moderate distances, but still stretch the limits of today s technology. In recent studies, a 100 kWe-class "Power Plug" Satellite and a 10 kWe-class Lunar Polar Solar Power outpost have been considered as the first steps in using these WPT options for SSP. Our current assessments include consideration of orbits, wavelengths, and structural designs to meet commercial, civilian government, and military needs. Notional transmitter and receiver sizes are considered for use in supplying 5 to 40 MW of power. In the longer term, lunar or asteroidal material can be used. By using SSP and WPT technology for near-term missions, we gain experience needed for sound decisions in designing and developing larger systems to send power from space to Earth.

  9. Solar dynamic power module design

    Science.gov (United States)

    Secunde, Richard R.; Labus, Thomas L.; Lovely, Ronald G.

    1989-01-01

    Studies have shown that the use of solar dynamic (SD) power for the growth areas of the Space Station Freedom program will result in life cycle cost savings when compared to power supplied by photovoltaic sources. In the SD power module, a concentrator collects and focuses solar energy into a heat receiver which has integral thermal energy storage. A Power Conversion Unit (PCU) based on the closed Brayton cycle removes thermal energy from the receiver and converts that energy to electrical energy. Since the closed Brayton cycle is a single phase gas cycle, the conversion hardware (heat exchangers, turbine, compressor, etc.) can be designed for operation in low earth orbit, and tested with confidence in test facilities on earth before launch into space. The concentrator subassemblies will be aligned and the receiver/PCU/radiator combination completely assembled and charged with gas and cooling liquid on earth before launch to, and assembly on, orbit.

  10. Peak Power Markets for Satellite Solar Power

    Science.gov (United States)

    Landis, Geoffrey A.

    2002-01-01

    This paper introduces first Indonesia, comprises 15,000 islands, has land area of two millions square kilometers. Extending from 95 to 141 degrees East longitude and from 6 degrees North to 11 degrees South latitude. Further the market of the Space Solar Power/SPS must be worldwide, including Indonesia. As we know, it can provide electricity anywhere in the world from the Earth's orbit, mostly Indonesia an equator country. We have to perform case studies of various countries to understand their benefits and disadvantages provided by the SSP, because each country has much different condition on energy from other countries. We are at the moment starting the international collaboration between Indonesia and Japan to carry out the case study for Indonesia. We understand that in Indonesia itself each province has much different micro-climate between one province compared to the other. In Japan, METI (Ministry of Economy, Trade and Industry) has already organized a committee to investigate the feasibility of Space Solar Power and to make a plan to launch a space demonstration of the SPS. While, Indonesia is quickly developing economy and increasing their energy demand. We are investigating the detailed energy conditions of Indonesia, the benefits and disadvantages of the Space Solar Power for Indonesia. Especially, we will perform the investigation on the receiving system for the Japanese pilot Space Power Satellite.

  11. Solar Powered Electronic Trash Can

    OpenAIRE

    Engr. Joan P. Lazaro; Engr. Alexis John M. Rubio

    2014-01-01

    The purpose of this study is to create an improvement of a normal trash can using an embedded systemintegrated with a solar panel that aims to improve the disposal practices of schoolchildren and improve the awareness of the students about the emerging capability of solar power. To use the system, the user needs to scan the material of the garbage then the chamber opens depending on what type of material was scanned. As the chamber opens, the user throws the trash inside the chamb...

  12. Modular Solar Electric Power (MSEP) Systems (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Hassani, V.

    2000-06-18

    This presentation discusses the development and deployment of Modular Solar Electric Power (MSEP) systems, the feasibility of application of existing binary power cycles to solar trough technology, and identification of next action items.

  13. Mechanism of Cyclically Polarity Reversing Solar Magnetic Cycle as ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We briefly describe historical development of the concept of solar dynamo mechanism that generates electric current and magnetic field by plasma ... The dynamo is the driver of the cyclically polarity reversing solar magnetic cycle. ... Department of Astronomy, University of Tokyo, Tokyo, Japan 113-0033.

  14. Chapter 11: Concentrating Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, Craig S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Stekli, J. [U.S. Department of Energy; Bueno, P. C. [Southwest Research Institute

    2017-01-02

    This chapter summarizes the applications of the supercritical CO2 (sCO2) Brayton cycle in concentrating solar power (CSP) plants. The design and operation of CSP plants are reviewed to highlight the requirements for the power cycle and attributes that are advantageous for the solar-thermal application. The sCO2 Brayton cycle offers the potential of higher cycle efficiency versus superheated or supercritical steam cycles at temperatures relevant for CSP applications. In addition, Brayton cycle systems using sCO2 are anticipated to have smaller weight and volume, lower thermal mass, and less complex power blocks compared with Rankine cycles due to the higher density of the fluid and simpler cycle design. The simpler machinery and compact size of the sCO2 process may also reduce the installation, maintenance, and operation cost of the system. Power cycle capacities in the range of 10-150 MWe are anticipated for the CSP application. In this chapter, we explore sCO2 Brayton cycle configurations that have attributes that are desirable from the perspective of a CSP application, such as the ability to accommodate dry cooling and daily cycling, as well as integration with thermal energy storage.

  15. Solar Powered Electronic Trash Can

    Directory of Open Access Journals (Sweden)

    Engr. Joan P. Lazaro

    2014-10-01

    Full Text Available The purpose of this study is to create an improvement of a normal trash can using an embedded systemintegrated with a solar panel that aims to improve the disposal practices of schoolchildren and improve the awareness of the students about the emerging capability of solar power. To use the system, the user needs to scan the material of the garbage then the chamber opens depending on what type of material was scanned. As the chamber opens, the user throws the trash inside the chamber, it has 10 seconds to dispose of the trash then the chamber will automatically close. A message appears in the matrix board whether the user had successfully disposed of the trash. The framework of the system discusses the procedure in constructing the propose project. It consists of the input, the processes, and the output. Inputs consist of the software and the hardware requirements. A vital part of the software development is the coding of the embedded system and on hardware development is the construction of the mechanism, after this phase the user tests it for possible enhancement and revision to be incorporated in the mechanism. The output of the system must be a fully functional mechanism that can be executed completely by the user.Upon thorough research, the proponents developed a Solar Powered Electronic Trash Can that helps school-children in proper disposing of their trash. This can also affects the pollution rating by means of proper trash segregation.

  16. Pv-Thermal Solar Power Assembly

    Science.gov (United States)

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

    2001-10-02

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

  17. Solar-powered cooling system

    Science.gov (United States)

    Farmer, Joseph C.

    2015-07-28

    A solar-powered adsorption-desorption refrigeration and air conditioning system that uses nanostructural materials such as aerogels, zeolites, and sol gels as the adsorptive media. Refrigerant molecules are adsorbed on the high surface area of the nanostructural material while the material is at a relatively low temperature, perhaps at night. During daylight hours, when the nanostructural materials is heated by the sun, the refrigerant are thermally desorbed from the surface of the aerogel, thereby creating a pressurized gas phase in the vessel that contains the aerogel. This solar-driven pressurization forces the heated gaseous refrigerant through a condenser, followed by an expansion valve. In the condenser, heat is removed from the refrigerant, first by circulating air or water. Eventually, the cooled gaseous refrigerant expands isenthalpically through a throttle valve into an evaporator, in a fashion similar to that in more conventional vapor recompression systems.

  18. Solar thermal power: the seamless solar link to the conventional power world

    International Nuclear Information System (INIS)

    Geyer, Michael; Quaschning, Volker

    2000-01-01

    This article focuses on solar thermal power generation and describes two solar thermal power concepts, namely, the parabolic trough or solar farm, and the solar central receiver or power tower. Details are given of grid-connected parabolic trough power plants in California and recent developments in collector design and absorber tubes, and the operation of power tower plants with different heat transfer media. Market issues are discussed, and solar thermal power projects under development, and application for support for solar thermal power projects under the Global Environment Facility's Operational Programme by Egypt, India, Iran, Mexico and Morocco are reported

  19. Dispatchable Solar Power Plant Project

    Energy Technology Data Exchange (ETDEWEB)

    Price, Henry [Solar Dynamics LLC, Broomfield, CO (United States)

    2018-01-31

    As penetration of intermittent renewable power increases, grid operators must manage greater variability in the supply and demand on the grid. One result is that utilities are planning to build many new natural gas peaking power plants that provide added flexibility needed for grid management. This report discusses the development of a dispatchable solar power (DSP) plant that can be used in place of natural gas peakers. Specifically, a new molten-salt tower (MST) plant has been developed that is designed to allow much more flexible operation than typically considered in concentrating solar power plants. As a result, this plant can provide most of the capacity and ancillary benefits of a conventional natural gas peaker plant but without the carbon emissions. The DSP system presented was designed to meet the specific needs of the Arizona Public Service (APS) utility 2017 peaking capacity request for proposals (RFP). The goal of the effort was to design a MST peaker plant that had the operational capabilities required to meet the peaking requirements of the utility and be cost competitive with the natural gas alternative. The effort also addresses many perceived barriers facing the commercial deployment of MST technology in the US today. These include MST project development issues such as permitting, avian impacts, visual impacts of tower CSP projects, project schedule, and water consumption. The DSP plant design is based on considerable analyses using sophisticated solar system design tools and in-depth preliminary engineering design. The resulting DSP plant design uses a 250 MW steam power cycle, with solar field designed to fit on a square mile plot of land that has a design point thermal rating of 400 MWt. The DSP plant has an annual capacity factor of about 16% tailored to deliver greater than 90% capacity during the critical Arizona summer afternoon peak. The table below compares the All-In energy cost and capacity payment of conventional combustion turbines

  20. Nanostructured electrodes for Solar Power Generation Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The key to achieving high-power solar arrays for NASA applications is the development of high-efficiency, thin-film solar cells that can be fabricated directly on...

  1. Technology Roadmaps: Concentrating Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-07-01

    The emerging technology known as concentrating solar power, or CSP, holds much promise for countries with plenty of sunshine and clear skies. Its electrical output matches well the shifting daily demand for electricity in places where airconditioning systems are spreading. When backed up by thermal storage facilities and combustible fuel, it offers utilities electricity that can be dispatched when required, enabling it to be used for base, shoulder and peak loads. Within about one to two decades, it will be able to compete with coal plants that emit high levels of CO2. The sunniest regions, such as North Africa, may be able to export surplus solar electricity to neighbouring regions, such as Europe, where demand for electricity from renewable sources is strong. In the medium-to-longer term, concentrating solar facilities can also produce hydrogen, which can be blended with natural gas, and provide low-carbon liquid fuels for transport and other end-use sectors. For CSP to claim its share of the coming energy revolution, concerted action is required over the next ten years by scientists, industry, governments, financing institutions and the public. This roadmap is intended to help drive these indispensable developments.

  2. Simulating solar power plant variability :

    Energy Technology Data Exchange (ETDEWEB)

    Lave, Matthew Samuel; Ellis, Abraham; Stein, Joshua.

    2013-06-01

    It is important to be able to accurately simulate the variability of solar PV power plants for grid integration studies. We aim to inform integration studies of the ease of implementation and application-specific accuracy of current PV power plant output simulation methods. This report reviews methods for producing simulated high-resolution (sub-hour or even sub-minute) PV power plant output profiles for variability studies and describes their implementation. Two steps are involved in the simulations: estimation of average irradiance over the footprint of a PV plant and conversion of average irradiance to plant power output. Six models are described for simulating plant-average irradiance based on inputs of ground-measured irradiance, satellite-derived irradiance, or proxy plant measurements. The steps for converting plant-average irradiance to plant power output are detailed to understand the contributions to plant variability. A forthcoming report will quantify the accuracy of each method using application-specific validation metrics.

  3. Solar Power Generation in Extreme Space Environments

    Science.gov (United States)

    Elliott, Frederick W.; Piszczor, Michael F.

    2016-01-01

    The exploration of space requires power for guidance, navigation, and control; instrumentation; thermal control; communications and data handling; and many subsystems and activities. Generating sufficient and reliable power in deep space through the use of solar arrays becomes even more challenging as solar intensity decreases and high radiation levels begin to degrade the performance of photovoltaic devices. The Extreme Environments Solar Power (EESP) project goal is to develop advanced photovoltaic technology to address these challenges.

  4. Concentrating Solar Power. Technology Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-10-15

    Concentrating solar power can contribute significantly to the world's energy supply. As shown in this roadmap, this decade is a critical window of opportunity during which CSP could become a competitive source of electrical power to meet peak and intermediate loads in the sunniest parts of the world. This roadmap identifies technology, economy and policy goals and milestones needed to support the development and deployment of CSP, as well as ongoing advanced research in CSF. It also sets out the need for governments to implement strong, balanced policies that favour rapid technological progress, cost reductions and expanded industrial manufacturing of CSP equipment to enable mass deployment. Importantly, this roadmap also establishes a foundation for greater international collaboration. The overall aim of this roadmap is to identify actions required - on the part of all stakeholders - to accelerate CSP deployment globally. Many countries, particularly in emerging regions, are only just beginning to develop CSP. Accordingly, milestone dates should be considered as indicative of urgency, rather than as absolutes. This roadmap is a work in progress. As global CSP efforts advance and an increasing number of CSP applications are developed, new data will provide the basis for updated analysis. The IEA will continue to track the evolution of CSP technology and its impacts on markets, the power sector and regulatory environments, and will update its analysis and set additional tasks and milestones as new learning comes to light.

  5. Space Solar Power Program. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Arif, Humayun; Barbosa, Hugo; Bardet, Christophe; Baroud, Michel; Behar, Alberto; Berrier, Keith; Berthe, Phillipe; Bertrand, Reinhold; Bibyk, Irene; Bisson, Joel; Bloch, Lawrence; Bobadilla, Gabriel; Bourque, Denis; Bush, Lawrence; Carandang, Romeo; Chiku, Takemi; Crosby, Norma; De Seixas, Manuel; De Vries, Joha; Doll, Susan; Dufour, Francois; Eckart, Peter; Fahey, Michael; Fenot, Frederic; Foeckersperger, Stefan; Fontaine, Jean-Emmanuel; Fowler, Robert; Frey, Harald; Fujio, Hironobu; Gasa, Jaume Munich; Gleave, Janet; Godoe, Jostein; Green, Iain; Haeberli, Roman; Hanada, Toshiya; Harris, Peter; Hucteau, Mario; Jacobs, Didier Fernand; Johnson, Richard; Kanno, Yoshitsugu; Koenig, Eva Maria; Kojima, Kazuo; Kondepudi, Phani; Kottbauer, Christian; Kulper, Doede; Kulagin, Konstantin; Kumara, Pekka; Kurz, Rainer; Laaksonen, Jyrki; Lang, Andrew Neill; Lathan, Corinna; Le Fur, Thierry; Lewis, David; Louis, Alain; Mori, Takeshi; Morlanes, Juan; Murbach, Marcus; Nagatomo, Hideo; O' brien, Ivan; Paines, Justin; Palaszewski, Bryan; Palmnaes, Ulf; Paraschivolu, Marius; Pathare, Asmin; Perov, Egor; Persson, Jan; Pessoa-Lopes, Isabel; Pinto, Michel; Porro, Irene; Reichert, Michael; Ritt-Fischer, Monika; Roberts, Margaret; Robertson II, Lawrence; Rogers, Keith; Sasaki, Tetsuo; Scire, Francesca; Shibatou, Katsuya; Shirai, Tatsuya; Shiraishi, Atsushi; Soucaille, Jean-Francois; Spivack, Nova; St. Pierre, Dany; Suleman, Afzal; Sullivan, Thomas; Theelen, Bas Johan; Thonstad, Hallvard; Tsuji, Masatoshi; Uchiumi, Masaharu; Vidqvist, Jouni; Warrell, David; Watanabe, Takafumi; Willis, Richard; Wolf, Frank; Yamakawa, Hiroshi; Zhao, Hong

    1992-08-01

    Information pertaining to the Space Solar Power Program is presented on energy analysis; markets; overall development plan; organizational plan; environmental and safety issues; power systems; space transportation; space manufacturing, construction, operations; design examples; and finance.

  6. Space solar power - An energy alternative

    Science.gov (United States)

    Johnson, R. W.

    1978-01-01

    The space solar power concept is concerned with the use of a Space Power Satellite (SPS) which orbits the earth at geostationary altitude. Two large symmetrical solar collectors convert solar energy directly to electricity using photovoltaic cells woven into blankets. The dc electricity is directed to microwave generators incorporated in a transmitting antenna located between the solar collectors. The antenna directs the microwave beam to a receiving antenna on earth where the microwave energy is efficiently converted back to dc electricity. The SPS design promises 30-year and beyond lifetimes. The SPS is relatively pollution free as it promises earth-equivalence of 80-85% efficient ground-based thermal power plant.

  7. Photovoltaics: A Solar Technology for Powering Tomorrow.

    Science.gov (United States)

    Flavin, Christopher

    1983-01-01

    Photovoltaics, the technology that converts sunlight directly into electricity, may soon be a reliable power source for the world's poor. The one major challenge is cost reduction. Many topics are discussed, including solar powering the Third World, designing the solar building, investing in the sun, and the future of photovoltaics. (NW)

  8. Solar power pumping system for domestic appliences

    OpenAIRE

    Lukhwareni, T.; Gouws, R.; Dobzhanskyi, O.

    2014-01-01

    With the world encountering huge pollution problems, use of renewable energy is being encouraged in place of fossils fuels for electricity generation. On such renewable energies is solar power. Solar powered systems are able to generate electricity using photovoltaic (PV) panels, or thermal collectors directly from sunlight. Pool pump electricity consumption has also risen in South Africa. This paper presents the results of the design, and construction of a PV solar system to effect water pum...

  9. PV/thermal solar power assembly

    Science.gov (United States)

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

    2004-01-13

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

  10. Shuttle Engine Designs Revolutionize Solar Power

    Science.gov (United States)

    2014-01-01

    The Space Shuttle Main Engine was built under contract to Marshall Space Flight Center by Rocketdyne, now part of Pratt & Whitney Rocketdyne (PWR). PWR applied its NASA experience to solar power technology and licensed the technology to Santa Monica, California-based SolarReserve. The company now develops concentrating solar power projects, including a plant in Nevada that has created 4,300 jobs during construction.

  11. Maximum Power from a Solar Panel

    Directory of Open Access Journals (Sweden)

    Michael Miller

    2010-01-01

    Full Text Available Solar energy has become a promising alternative to conventional fossil fuel sources. Solar panels are used to collect solar radiation and convert it into electricity. One of the techniques used to maximize the effectiveness of this energy alternative is to maximize the power output of the solar collector. In this project the maximum power is calculated by determining the voltage and the current of maximum power. These quantities are determined by finding the maximum value for the equation for power using differentiation. After the maximum values are found for each time of day, each individual quantity, voltage of maximum power, current of maximum power, and maximum power is plotted as a function of the time of day.

  12. Solar power water distillation unit

    Science.gov (United States)

    Hameed, Kamran; Muzammil Khan, Muhammad; Shahrukh Ateeq, Ijlal; Omair, Syed Muhammad; Ahmer, Muhammad; Wajid, Abdul

    2013-06-01

    Clean drinking water is the basic necessity for every human being, but about 1.1 billion people in the world lacked proper drinking water. There are many different types of water purification processes such as filtration, reverse osmosis, ultraviolet radiation, carbon absorption, but the most reliable processes are distillation and boiling. Water purification, such as distillation, is especially important in regions where water resources or tap water is not suitable for ingesting without boiling or chemical treatment. In design project It treats the water by combining different methods such as Filtration, Distillation and a technique called concentrated solar power (CSP). Distillation is literally the method seen in nature, whereby: the sun heats the water on the earth's surface, the water is turned into a vapor (evaporation) and rises, leaving contaminants behind, to form clouds. As the upper atmosphere drops in temperature the vapors cool and convert back to water to form water. In this project distillation is achieved by using a parabolic mirror which boils water at high temperature. Filtration is done by sand filter and carbon filter. First sand filter catches the sand particles and the carbon filter which has granules of active carbon is used to remove odor dissolved gases from water. This is the Pre-treatment of water. The filtered water is then collected in a water container at a focus of parabolic mirror where distillation process is done. Another important feature of designed project is the solar tracking of a parabolic mirror which increases the efficiency of a parabolic mirror [1],[2].

  13. Solar power water distillation unit

    International Nuclear Information System (INIS)

    Hameed, Kamran; Khan, Muhammad Muzammil; Ateeq, Ijlal Shahrukh; Omair, Syed Muhammad; Ahmer, Muhammad; Wajid, Abdul

    2013-01-01

    Clean drinking water is the basic necessity for every human being, but about 1.1 billion people in the world lacked proper drinking water. There are many different types of water purification processes such as filtration, reverse osmosis, ultraviolet radiation, carbon absorption, but the most reliable processes are distillation and boiling. Water purification, such as distillation, is especially important in regions where water resources or tap water is not suitable for ingesting without boiling or chemical treatment. In design project It treats the water by combining different methods such as Filtration, Distillation and a technique called concentrated solar power (CSP). Distillation is literally the method seen in nature, whereby: the sun heats the water on the earth's surface, the water is turned into a vapor (evaporation) and rises, leaving contaminants behind, to form clouds. As the upper atmosphere drops in temperature the vapors cool and convert back to water to form water. In this project distillation is achieved by using a parabolic mirror which boils water at high temperature. Filtration is done by sand filter and carbon filter. First sand filter catches the sand particles and the carbon filter which has granules of active carbon is used to remove odor dissolved gases from water. This is the Pre-treatment of water. The filtered water is then collected in a water container at a focus of parabolic mirror where distillation process is done. Another important feature of designed project is the solar tracking of a parabolic mirror which increases the efficiency of a parabolic mirror [1],[2].

  14. Comparing thermal and photovoltaic solar power plants

    International Nuclear Information System (INIS)

    Casal, F.G.

    1993-01-01

    A large number of solar thermal power plants of the ''central receiver'' type using air as the heat transfer medium are modeled and their economics are compared with those of their solar photovoltaic counterparts. Those parameters which most significantly affect the production costs of the solar thermal plants are identified and their possible significance for the evaluation of non-electric uses of concentrated solar radiation is discussed. For solar thermal applications the solar multiple has much less impact on the production costs than the costs of the heliostats and of the thermal storage. Areas identifying the superior economic performance of solar thermal power plants versus photovoltaic systems were identified and are presented as graphs of boundaries of equal performance under identical conditions. (Author) 11 refs

  15. Liquid metals for solar power systems

    Science.gov (United States)

    Flesch, J.; Niedermeier, K.; Fritsch, A.; Musaeva, D.; Marocco, L.; Uhlig, R.; Baake, E.; Buck, R.; Wetzel, T.

    2017-07-01

    The use of liquid metals in solar power systems is not new. The receiver tests with liquid sodium in the 1980s at the Plataforma Solar de Almería (PSA) already proved the feasibility of liquid metals as heat transfer fluid. Despite the high efficiency achieved with that receiver, further investigation of liquid metals in solar power systems was stopped due to a sodium spray fire. Recently, the topic has become interesting again and the gained experience during the last 30 years of liquid metals handling is applied to the concentrated solar power community. In this paper, recent activities of the Helmholtz Alliance LIMTECH concerning liquid metals for solar power systems are presented. In addition to the components and system simulations also the experimental setup and results are included.

  16. The Lyman-alpha Imager onboard Solar Polar Orbit Telescope

    Science.gov (United States)

    Li, Baoquan; Li, Haitao; Zhou, Sizhong; Jiang, Bo

    2013-12-01

    Solar Polar ORbit Telescope (SPORT) was originally proposed in 2004 by the National Space Science Center, Chinese Academy of Sciences, which is currently being under background engineering study phase in China. SPORT will carry a suite of remote-sensing and in-situ instruments to observe coronal mass ejections (CMEs), solar high-latitude magnetism, and the fast solar wind from a polar orbit around the Sun. The Lyman-alpha Imager (LMI) is one of the key remotesensing instruments onboard SPORT with 45arcmin FOV, 2000mm effective focal length and 1.4arcsec/pixel spatial resolution . The size of LMI is φ150×1000mm, and the weight is less than10kg, including the 7kg telescope tube and 3kg electronic box. There are three 121.6nm filters used in the LMI optical path, so the 98% spectral purity image of 121.6nm can be achieved. The 121.6nm solar Lyman-alpha line is produced in the chromosphere and very sensitive to plasma temperature, plasma velocity and magnetism variation in the chromosphere. Solar Lyman-alpha disk image is an ideal tracker for corona magnetism variation.

  17. Recipe for success in solar power marketing

    International Nuclear Information System (INIS)

    Frauenfelder, S.

    2000-01-01

    This article presents the results of a campaign run jointly by the Swiss Federal Office of Energy and the Association of Swiss Electricity Utilities called 'Solar Power from your Utility'. An analysis of solar power marketing efforts made by ten utilities is presented. The results of assessments of these market measures made by solar power customers and non-customers are presented and questions of pricing, product-image and product-confidence are discussed. Finally, suggestions for the optimisation of the marketing measures are made

  18. Solar energy powered microbial fuel cell with a reversible bioelectrode.

    Science.gov (United States)

    Strik, David P B T B; Hamelers, Hubertus V M; Buisman, Cees 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 cells is the pH membrane gradient which reduces cell voltage and power output. This problem is caused by acid production at the anode, alkaline production at the cathode, and the nonspecific proton exchange through the membrane. Here we report a solution for a new kind of solar energy powered microbial fuel cell via development of a reversible bioelectrode responsible for both biocatalyzed anodic and cathodic electron transfer. Anodic produced protons were used for the cathodic reduction reaction which held the formation of a pH membrane gradient. The microbial fuel cell continuously generated electricity and repeatedly reversed polarity dependent on aeration or solar energy exposure. Identified organisms within biocatalyzing biofilm of the reversible bioelectrode were algae, (cyano)bacteria and protozoa. These results encourage application of solar energy powered microbial fuel cells.

  19. Experimental Investigation of Solar Powered Reverse Osmosis ...

    African Journals Online (AJOL)

    fire7-

    due to its low energy consumption is one of the best desalination alternatives. Solar powered reverse osmosis system was developed and installed at Mekelle University. The main components are photovoltaic panels, two DC powered pumps, carbon filters, and flow meters. The system made to operate in a variable power, ...

  20. Solar small-scale dynamo and polarity of sunspot groups

    Science.gov (United States)

    Sokoloff, D.; Khlystova, A.; Abramenko, V.

    2015-08-01

    In order to clarify a possible role of small-scale dynamo in formation of solar magnetic field, we suggest an observational test for small-scale dynamo action based on statistics of anti-Hale sunspot groups. As we have shown, according to theoretical expectations the small-scale dynamo action has to provide a population of sunspot groups which do not follow the Hale polarity law, and the density of such groups on the time-latitude diagram is expected to be independent on the phase of the solar cycle. Correspondingly, a percentage of the anti-Hale groups is expected to reach its maximum values during solar minima. For several solar cycles, we considered statistics of anti-Hale groups obtained by several scientific teams, including ours, to find that the percentage of anti-Hale groups becomes indeed maximal during a solar minimum. Our interpretation is that this fact may be explained by the small-scale dynamo action inside the solar convective zone.

  1. Solar-powered air-conditioning

    Science.gov (United States)

    Clark, D. C.; Rousseau, J.

    1977-01-01

    Report focuses on recent study on development of solar-powered residential air conditioners and is based on selected literature through 1975. Its purposes are to characterize thermal and mechanical systems that might be useful in development of Rankine-cycle approach to solar cooling and assessment of a Lithium Bromide/Water absorption cycle system.

  2. Solar Power for Future NASA Missions

    Science.gov (United States)

    Bailey, Sheila G.; Landis, Geoffrey A.

    2014-01-01

    An overview of NASA missions and technology development efforts are discussed. Future spacecraft will need higher power, higher voltage, and much lower cost solar arrays to enable a variety of missions. One application driving development of these future arrays is solar electric propulsion.

  3. Advancing Concentrating Solar Power Research (Fact Sheet)

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2014-02-01

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

  4. Consumer attitudes towards domestic solar power systems

    International Nuclear Information System (INIS)

    Faiers, Adam; Neame, Charles

    2006-01-01

    The success of the UK policy to reduce carbon emissions is partly dependent on the ability to persuade householders to become more energy efficient, and to encourage installation of domestic solar systems. Solar power is an innovation in the UK but the current policy of stimulating the market with grants is not resulting in widespread adoption. This case study, using householders in central England, investigates householder attitudes towards characteristics of solar systems and identifies some of the barriers to adoption. The study utilises Diffusion of Innovations theory to identify attitudes towards system attributes, and isolates the characteristics that are preventing a pragmatic 'early majority' from adopting the technology. A group of 'early adopters', and a group of assumed 'early majority' adopters of solar power were surveyed and the results show that overall, although the 'early majority' demonstrate a positive perception of the environmental characteristics of solar power, its financial, economic and aesthetic characteristics are limiting adoption. Differences exist between the two groups showing support for the concept of a 'chasm' between adopter categories after Moore (Crossing the Chasm: Marketing and Selling High-tech Products to Mainstream Customers, second ed. Harper Perennial, New York). However, if consumers cannot identify the relative advantage of solar power over their current sources of power, which is supplied readily and cheaply through a mains system, it is unlikely that adoption will follow. Recommendations concerning the marketing and development of solar products are identified

  5. Low-cost solar electric power

    CERN Document Server

    Fraas, Lewis M

    2014-01-01

    ?This book describes recent breakthroughs that promise major cost reductions in solar energy production in a clear and highly accessible manner. The author addresses the three key areas that have commonly resulted in criticism of solar energy in the past: cost, availability, and variability. Coverage includes cutting-edge information on recently developed 40? efficient solar cells, which can produce double the power of currently available commercial cells. The discussion also highlights the potentially transformative emergence of opportunities for integration of solar energy storage and natura

  6. Online Short-term Solar Power Forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Nielsen, Henrik Aalborg

    This poster presents two approaches to online forecasting of power production from PV systems. The methods are suited for online forecasting in many applications and here they are used to predict hourly values of solar power for horizons up to 32 hours.......This poster presents two approaches to online forecasting of power production from PV systems. The methods are suited for online forecasting in many applications and here they are used to predict hourly values of solar power for horizons up to 32 hours....

  7. Online Short-term Solar Power Forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Nielsen, Henrik Aalborg

    2011-01-01

    This poster presents two approaches to online forecasting of power production from PV systems. The methods are suited for online forecasting in many applications and here they are used to predict hourly values of solar power for horizons up to 32 hours.......This poster presents two approaches to online forecasting of power production from PV systems. The methods are suited for online forecasting in many applications and here they are used to predict hourly values of solar power for horizons up to 32 hours....

  8. Materials in Harnessing Solar Power

    Indian Academy of Sciences (India)

    64

    Mission (JNNSM) [8] to boost India's solar energy harnessing capability. The mission document .... Through “The Solar Mission 2020”, Government of India has projected various goals and time-lines to ...... [40] Kim H S, Lee C R, Im J H, Lee K B, Moehl T, Marchioro A, Moon S J, Humphry-Baker. R, Yum J H, Moser J E, ...

  9. Solar thermal electric power information user study

    Energy Technology Data Exchange (ETDEWEB)

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

    1981-02-01

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

  10. PowerSat: A technology demonstration of a solar power satellite

    Science.gov (United States)

    Sigler, Douglas L. (Editor); Riedman, John; Duracinski, Jon; Edwards, Joe; Brown, Garry; Webb, Ron; Platzke, Mike; Yuan, Xiaolin; Rogers, Pete; Khan, Afsar

    1994-01-01

    PowerSat is a preliminary design strategy for microwave wireless power transfer of solar energy. Solar power satellites convert solar power into microwave energy and use wireless power transmission to transfer the power to the Earth's surface. The PowerSat project will show how new developments in inflatable technology can be used to deploy solar panels and phased array antennas.

  11. Swiss solar power statistics 2007 - Significant expansion

    International Nuclear Information System (INIS)

    Hostettler, T.

    2008-01-01

    This article presents and discusses the 2007 statistics for solar power in Switzerland. A significant number of new installations is noted as is the high production figures from newer installations. The basics behind the compilation of the Swiss solar power statistics are briefly reviewed and an overview for the period 1989 to 2007 is presented which includes figures on the number of photovoltaic plant in service and installed peak power. Typical production figures in kilowatt-hours (kWh) per installed kilowatt-peak power (kWp) are presented and discussed for installations of various sizes. Increased production after inverter replacement in older installations is noted. Finally, the general political situation in Switzerland as far as solar power is concerned are briefly discussed as are international developments.

  12. Solar Powered Automatic Shrimp Feeding System

    Directory of Open Access Journals (Sweden)

    Dindo T. Ani

    2015-12-01

    Full Text Available - Automatic system has brought many revolutions in the existing technologies. One among the technologies, which has greater developments, is the solar powered automatic shrimp feeding system. For instance, the solar power which is a renewable energy can be an alternative solution to energy crisis and basically reducing man power by using it in an automatic manner. The researchers believe an automatic shrimp feeding system may help solve problems on manual feeding operations. The project study aimed to design and develop a solar powered automatic shrimp feeding system. It specifically sought to prepare the design specifications of the project, to determine the methods of fabrication and assembly, and to test the response time of the automatic shrimp feeding system. The researchers designed and developed an automatic system which utilizes a 10 hour timer to be set in intervals preferred by the user and will undergo a continuous process. The magnetic contactor acts as a switch connected to the 10 hour timer which controls the activation or termination of electrical loads and powered by means of a solar panel outputting electrical power, and a rechargeable battery in electrical communication with the solar panel for storing the power. By undergoing through series of testing, the components of the modified system were proven functional and were operating within the desired output. It was recommended that the timer to be used should be tested to avoid malfunction and achieve the fully automatic system and that the system may be improved to handle changes in scope of the project.

  13. Online short-term solar power forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Nielsen, Henrik Aalborg

    2009-01-01

    This paper describes a new approach to online forecasting of power production from PV systems. The method is suited to online forecasting in many applications and in this paper it is used to predict hourly values of solar power for horizons of up to 36 hours. The data used is fifteen-minute obser......This paper describes a new approach to online forecasting of power production from PV systems. The method is suited to online forecasting in many applications and in this paper it is used to predict hourly values of solar power for horizons of up to 36 hours. The data used is fifteen......-minute observations of solar power from 21 PV systems located on rooftops in a small village in Denmark. The suggested method is a two-stage method where first a statistical normalization of the solar power is obtained using a clear sky model. The clear sky model is found using statistical smoothing techniques....... Then forecasts of the normalized solar power are calculated using adaptive linear time series models. Both autoregressive (AR) and AR with exogenous input (ARX) models are evaluated, where the latter takes numerical weather predictions (NWPs) as input. The results indicate that for forecasts up to two hours...

  14. Velocity fluctuations in polar solar wind: a comparison between different solar cycles

    Directory of Open Access Journals (Sweden)

    B. Bavassano

    2009-02-01

    Full Text Available The polar solar wind is a fast, tenuous and steady flow that, with the exception of a relatively short phase around the Sun's activity maximum, fills the high-latitude heliosphere. The polar wind properties have been extensively investigated by Ulysses, the first spacecraft able to perform in-situ measurements in the high-latitude heliosphere. The out-of-ecliptic phases of Ulysses cover about seventeen years. This makes possible to study heliospheric properties at high latitudes in different solar cycles. In the present investigation we focus on hourly- to daily-scale fluctuations of the polar wind velocity. Though the polar wind is a quite uniform flow, fluctuations in its velocity do not appear negligible. A simple way to characterize wind velocity variations is that of performing a multi-scale statistical analysis of the wind velocity differences. Our analysis is based on the computation of velocity differences at different time lags and the evaluation of statistical quantities (mean, standard deviation, skewness, and kurtosis for the different ensembles. The results clearly show that, though differences exist in the three-dimensional structure of the heliosphere between the investigated solar cycles, the velocity fluctuations in the core of polar coronal holes exhibit essentially unchanged statistical properties.

  15. Velocity fluctuations in polar solar wind: a comparison between different solar cycles

    Directory of Open Access Journals (Sweden)

    B. Bavassano

    2009-02-01

    Full Text Available The polar solar wind is a fast, tenuous and steady flow that, with the exception of a relatively short phase around the Sun's activity maximum, fills the high-latitude heliosphere. The polar wind properties have been extensively investigated by Ulysses, the first spacecraft able to perform in-situ measurements in the high-latitude heliosphere. The out-of-ecliptic phases of Ulysses cover about seventeen years. This makes possible to study heliospheric properties at high latitudes in different solar cycles. In the present investigation we focus on hourly- to daily-scale fluctuations of the polar wind velocity. Though the polar wind is a quite uniform flow, fluctuations in its velocity do not appear negligible. A simple way to characterize wind velocity variations is that of performing a multi-scale statistical analysis of the wind velocity differences. Our analysis is based on the computation of velocity differences at different time lags and the evaluation of statistical quantities (mean, standard deviation, skewness, and kurtosis for the different ensembles. The results clearly show that, though differences exist in the three-dimensional structure of the heliosphere between the investigated solar cycles, the velocity fluctuations in the core of polar coronal holes exhibit essentially unchanged statistical properties.

  16. Solar vs. Fission Surface Power for Mars

    Science.gov (United States)

    Rucker, Michelle A.; Oleson, Steve; George, Pat; Landis, Geoffrey A.; Fincannon, James; Bogner, Amee; Jones, Robert E.; Turnbull, Elizabeth; Martini, Michael C.; Gyekenyesi, John Z.; hide

    2016-01-01

    A multi-discipline team of experts from the National Aeronautics and Space Administration (NASA) developed Mars surface power system point design solutions for two conceptual missions. The primary goal of this study was to compare the relative merits of solar- versus fission-powered versions of each surface mission. First, the team compared three different solar power options against a fission power system concept for a sub-scale, uncrewed demonstration mission. The 4.5 meter (m) diameter pathfinder lander's primary mission would be to demonstrate Mars entry, descent, and landing techniques. Once on the Martian surface, the lander's In Situ Resource Utilization (ISRU) payload would demonstrate liquid oxygen propellant production using atmospheric resources. For the purpose of this exercise, location was assumed to be at the Martian equator. The three solar concepts considered included a system that only operated during daylight hours (at roughly half the daily propellant production rate of a round-the-clock fission design), a battery-augmented system that operated through the night (matching the fission concept's propellant production rate), and a system that operated only during daylight, but at a higher rate (again, matching the fission concept's propellant production rate). Including 30% mass growth allowance, total payload masses for the three solar concepts ranged from 1,116 to 2,396 kg, versus the 2,686 kg fission power scheme. However, solar power masses are expected to approach or exceed the fission payload mass at landing sites further from the equator, making landing site selection a key driver in the final power system decision. The team also noted that detailed reliability analysis should be performed on daytime-only solar power schemes to assess potential issues with frequent ISRU system on/off cycling. Next, the team developed a solar-powered point design solution for a conceptual four-crew, 500-day surface mission consisting of up to four landers per

  17. A Comparison Of A Solar Power Satellite Concept To A Concentrating Solar Power System

    Science.gov (United States)

    Smitherman, David V.

    2013-01-01

    A comparison is made of a Solar Power Satellite concept in geostationary Earth orbit to a Concentrating Solar Power system on the ground to analyze overall efficiencies of each infrastructure from solar radiance at 1 AU to conversion and transmission of electrical energy into the power grid on the Earth's surface. Each system is sized for a 1-gigawatt output to the power grid and then further analyzed to determine primary collector infrastructure areas. Findings indicate that even though the Solar Power Satellite concept has a higher end-to-end efficiency, that the combined space and ground collector infrastructure is still about the same size as a comparable Concentrating Solar Power system on the ground.

  18. Solar powered desalination system using Fresnel lens

    Science.gov (United States)

    Sales, M. T. B. F.

    2016-11-01

    The Philippines is surrounded by coastal areas and these areas can be a potential source for potable water. This study aims to design and construct a solar powered desalination system using Fresnel lens. The experimental study was conducted using polluted salt water for the sample and desalination was carried out using the designed system. The desalination system was composed of the solar concentrator, solar still and the condenser system. The Fresnel lens was made of acrylic plastic and was an effective solar concentrator. Solar stills made of dark colored glass bottles were effective in absorbing the solar energy. The condenser system made of polybutylene and polystyrene were effective in condensing the vapor at ambient temperature. The shortest time of vaporization of the salt water was at 293 sec and the optimum angle of position of the lens was 36.42°. The amount of condensate collected was directly proportional to the amount of salt water in the solar still. The highest mean efficiency of the designed set-up was 34.82%. The water produced by the solar powered desalination system using Fresnel lens passed the standards set by WHO (World Health Organization) for drinking water.

  19. Polar ionospheric responses to solar wind IMF changes

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    2000-06-01

    Full Text Available Auroral and airglow emissions over Eureka (89° CGM during the 1997-98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and variable. During most of the period, Bz was northward and polar arcs were observed. Several overpasses by DMSP satellites during the four day period provided a clear picture of the particle precipitation producing the polar arcs. The spectral character of these events indicated excitation by electrons of average energy 300 to 500 eV. Only occasionally were electrons of average energy up to ~1 keV observed and these appeared transitory from the ground optical data. It is noted that polar arcs appear after sudden changes in IMF By, suggesting IMF control over arc initiation. When By is positive there is arc motion from dawn to dusk, while By is negative the motion is consistently dusk to dawn. F-region (anti-sunward convections were monitored through the period from 630.0 nm emissions. The convection speed was low (100-150 m/s when Bz was northward but increased to 500 m/s after Bz turned southward on January 20.Key words: Atmospheric composition and structure (airglow and aurora - Ionosphere (particle precipitation - Magnetospheric Physics (polar cap phenomena

  20. Environmental protection of the solar power satellite

    Science.gov (United States)

    Reiff, P. H.; Freeman, J. W.; Cooke, D. L.

    1980-01-01

    This paper examines theoretically several features of the interactions of the Solar Power Satellite (SPS) with its space environment. The leakage currents through the kapton and sapphire solar cell blankets are calculated. At geosynchronous orbit, this parasitic power loss is only 0.7%, and is easily compensated by oversizing. At low-earth orbit, the power loss is potentially much larger (3%), and anomalous arcing is expected for the high-voltage negative surfaces. Preliminary results of a three-dimensional self-consistent plasma and electric field computer program are presented, confirming the validity of the predictions made from the one-dimensional models. Lastly, the paper proposes magnetic shielding of the satellite, to reduce the power drain and to protect the solar cells from energetic electron and plasma ion bombardment. It is concluded that minor modifications from the baseline SPS design can allow the SPS to operate safely and efficiently in its space environment.

  1. Solar Versus Fission Surface Power for Mars

    Science.gov (United States)

    Rucker, Michelle A.; Oleson, Steve; George, Pat; Landis, Geoffrey A.; Fincannon, James; Bogner, Amee; Jones, Robert E.; Turnbull, Elizabeth; McNatt, Jeremiah; Martini, Michael C.; hide

    2016-01-01

    A multi-discipline team of experts from the National Aeronautics and Space Administration (NASA) developed Mars surface power system point design solutions for two conceptual missions to Mars using In-situ resource utilization (ISRU). The primary goal of this study was to compare the relative merits of solar- versus fission-powered versions of each surface mission. First, the team compared three different solar-power options against a fission power system concept for a sub-scale, uncrewed demonstration mission. This “pathfinder” design utilized a 4.5 meter diameter lander. Its primary mission would be to demonstrate Mars entry, descent, and landing techniques. Once on the Martian surface, the lander’s ISRU payload would demonstrate liquid oxygen propellant production from atmospheric resources. For the purpose of this exercise, location was assumed to be at the Martian equator. The three solar concepts considered included a system that only operated during daylight hours (at roughly half the daily propellant production rate of a round-the-clock fission design), a battery-augmented system that operated through the night (matching the fission concept’s propellant production rate), and a system that operated only during daylight, but at a higher rate (again, matching the fission concept’s propellant production rate). Including 30% mass growth allowance, total payload masses for the three solar concepts ranged from 1,128 to 2,425 kg, versus the 2,751 kg fission power scheme. However, solar power masses increase as landing sites are selected further from the equator, making landing site selection a key driver in the final power system decision. The team also noted that detailed reliability analysis should be performed on daytime-only solar power schemes to assess potential issues with frequent ISRU system on/off cycling.

  2. The place of solar power: an economic analysis of concentrated and distributed solar power

    OpenAIRE

    Banoni, Vanessa Arellano; Arnone, Aldo; Fondeur, Maria; Hodge, Annabel; Offner, J Patrick; Phillips, Jordan K

    2012-01-01

    Abstract Background This paper examines the cost and benefits, both financial and environmental, of two leading forms of solar power generation, grid-tied photovoltaic cells and Dish Stirling Systems, using conventional carbon-based fuel as a benchmark. Methods First we define how these solar technologies will be implemented and why. Then we delineate a model city and its characteristics, which will be used to test the two methods of solar-powered electric distribution. Then we set the constr...

  3. Cermet coatings for solar Stirling space power

    International Nuclear Information System (INIS)

    Jaworske, Donald A.; Raack, Taylor

    2004-01-01

    Cermet coatings, molecular mixtures of metal and ceramic, are being considered for the heat inlet surface of a solar Stirling space power convertor. The role of the cermet coating is to absorb as much of the incident solar energy as possible. The ability to mix metal and ceramic at the atomic level offers the opportunity to tailor the composition and the solar absorptance of these coatings. Several candidate cermet coatings were created and their solar absorptance was characterized as-manufactured and after exposure to elevated temperatures. Coating composition was purposely varied through the thickness of the coating. As a consequence of changing composition, islands of metal are thought to form in the ceramic matrix. Computer modeling indicated that diffusion of the metal atoms played an important role in island formation while the ceramic was important in locking the islands in place. Much of the solar spectrum is absorbed as it passes through this labyrinth

  4. Solar Power. Policy Overview and Good Practices

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Sadie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Walters, Terri [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Esterly, Sean [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Booth, Sarah [Booth Clean Energy LLC, Denver, CO (United States)

    2015-05-01

    As global electricity demand increases, governments are designing and implementing policies to scale up and catalyze renewable energy, which now meets 22% of global electricity demand (REN21 2014). Solar technologies are a critical component of this expanded deployment, and they have experienced unprecedented growth in recent years. As presented in Figure 1, solar prices have decreased significantly over the last decade (REN21 2014) and in 2013, new capacity installation of solar electricity from photovoltaics (PV) 1 surpassed all other renewable energy technologies worldwide—excluding hydropower—with 39 gigawatts installed that year. Concentrating solar thermal power,2 although it still represents a fairly nascent market, also continues to expand as installed capacity increased by 36% in 2013 compared to 2012. In addition to meeting energy demand in an increasingly cost-effective manner, solar deployment can also support critical economic, social, and environmental development goals (Flavin and Hull Aeck, n.d.).

  5. Solar thermal power systems. Program summary

    Energy Technology Data Exchange (ETDEWEB)

    1978-12-01

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

  6. Electrolysers Powered with Solar Energy

    Directory of Open Access Journals (Sweden)

    Ivaylo Y. Nedelchev

    2015-08-01

    Full Text Available The vast fossil fuel consumption and decreasing oil reserves and natural resources, enforce much more need of finding decision for renewable energies and development of constructions for using the so called green resources. One solution of this problem is combination ofalready established solar based sources and brown gas cell construction. Brown gas cell production is based on electrolysis of pure water and as a result generating a real gas fuel. This production can find large utility in different usages.

  7. Development of Solar Powered Irrigation System

    International Nuclear Information System (INIS)

    Abdelkerim, A I; Eusuf, M M R Sami; Salami, M J E; Aibinu, A; Eusuf, M A

    2013-01-01

    Development of a solar powered irrigation system has been discussed in this paper. This system would be SCADA-based and quite useful in areas where there is plenty of sunshine but insufficient water to carry out farming activities, such as rubber plantation, strawberry plantation, or any plantation, that requires frequent watering. The system is powered by solar system as a renewable energy which uses solar panel module to convert Sunlight into electricity. The development and implementation of an automated SCADA controlled system that uses PLC as a controller is significant to agricultural, oil and gas monitoring and control purpose purposes. In addition, the system is powered by an intelligent solar system in which solar panel targets the radiation from the Sun. Other than that, the solar system has reduced energy cost as well as pollution. The system is equipped with four input sensors; two soil moisture sensors, two level detection sensors. Soil moisture sensor measures the humidity of the soil, whereas the level detection sensors detect the level of water in the tank. The output sides consist of two solenoid valves, which are controlled respectively by two moistures sensors

  8. New directions for space solar power

    Science.gov (United States)

    Mankins, John C.

    2009-07-01

    Several of the central issues associated with the eventual realization of the vision of solar power from space for terrestrial markets resolve around the expect costs associated with the assembly, inspection, maintenance and repair of future solar power satellite (SPS) stations. In past studies (for example, NASA's "Fresh Look Study", c. 1995-1997) efforts were made to reduce both the scale and mass of large, systems-level interfaces (e.g., the power management and distribution (PMAD) system) and on-orbit fixed infrastructures through the use of modular systems strategies. These efforts have had mixed success (as reflected in the projected on-orbit mass of various systems concepts. However, the author remains convinced of the importance of modular strategies for exceptionally large space systems in eventually realizing the vision of power from space. This paper will introduce some of the key issues associated with cost-competitive space solar power in terrestrial markets. It will examine some of the relevant SPS concepts and will assess the 'pros and cons' of each in terms of space assembly, maintenance and servicing (SAMS) requirements. The paper discusses at a high level some relevant concepts and technologies that may play r role in the eventual, successful resolution of these challenges. The paper concludes with an example of the kind of novel architectural approach for space solar power that is needed.

  9. Materials in harnessing solar power

    Indian Academy of Sciences (India)

    2018-04-06

    Apr 6, 2018 ... reducing the usage of battery [12]. Further, a suitable battery such as Li ion battery can be used as a power backup. As per the present-day energy storage device technology, the battery design should be in such a way that it can provide a balance among specific energy and power, and life, obtaining ...

  10. Concentrating Solar Power. Report April 2009

    Energy Technology Data Exchange (ETDEWEB)

    Pihl, Erik (Chalmers Univ. of Technology, Enery and Environment, Goeteborg (Sweden))

    2009-04-15

    Concentrating solar power (CSP) technologies offer ways to utilise solar radiation by concentrating the light. In a concentrated form, the light can be utilised more cost efficiently. It is focused with mirrors or lenses and used either as a heat source in thermal power cycles (thermal CSP) or as a light source for high efficiency photovoltaic cells (concentrating photovoltaics, CPV). All concentrating systems use tracking to follow the movement of the sun, in two or three dimensions, and require direct sunlight (no diffusing clouds). CSP plants are often more complex, component wise than those based on flat PV. The extra cost of complexity is generally more than offset by the larger scales, the less need for expensive materials such as purified silicon and a better fit with the current energy infrastructure. Some thermal CSP plants offer great possibilities to deal with the intermittency of solar energy, as the heat generated can be stored in the form of a heated liquid in large tanks for many hours with little additional cost, and drive the thermal power generation also during cloudy periods or at night. CSP is growing rapidly and can be an important portion of future low-carbon energy systems. A prerequisite is that expected cost reductions are, at least largely, realised. In regions with good solar conditions (Mediterranean countries, US Southwest, Middle East, Australia etc), CSP systems already in the short-term future can satisfy significant shares of the power demand, to decrease CO{sub 2} emissions. Less solar-intensive regions (Northern Europe, much of North America etc) can be supplied with CSP power from solar-rich regions by using long distance power grids, for instance the high voltage DC cables being deployed and developed today

  11. Uncertainties in predicting solar panel power output

    Science.gov (United States)

    Anspaugh, B.

    1974-01-01

    The problem of calculating solar panel power output at launch and during a space mission is considered. The major sources of uncertainty and error in predicting the post launch electrical performance of the panel are considered. A general discussion of error analysis is given. Examples of uncertainty calculations are included. A general method of calculating the effect on the panel of various degrading environments is presented, with references supplied for specific methods. A technique for sizing a solar panel for a required mission power profile is developed.

  12. Inclined solar chimney for power production

    Energy Technology Data Exchange (ETDEWEB)

    Panse, S.V., E-mail: sudhirpanse@yahoo.com [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Jadhav, A.S.; Gudekar, A.S. [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Joshi, J.B. [Institute of Chemical Technology, Matunga, Mumbai 400 019 (India); Homi Bhabha National Institute, Trombay, Mumbai 400 094 (India)

    2011-09-15

    Highlights: {yields} Solar energy harnessing using inclined face of high mountains as solar chimney. {yields} Solar chimneys with structural stability, ease of construction and lower cost. {yields} Mathematical model developed, using complete (mechanical and thermal) energy balance. {yields} Can harness wind power also, as wind velocities at mountain top add to power output. {yields} Air temperature and velocity increase, as air rises in inclined chimney. - Abstract: The present concept of solar chimney is a tall vertical chimney constructed at the center of a large area, which is the collector. This creates questions about stability and economic viability of the chimney and also demands elaborate engineering techniques for constructing a tall chimney. We suggest geometry of 'Inclined Solar Chimney' (ISC), which is constructed along the face of a high rising mountain, on which maximum solar insolation is incident throughout the year. The chimney and the collector get merged here. This makes the structure stable, cost effective and easy for construction. A mathematical model has been developed considering the total energy balance. It predicts the temperature and velocity and kinetic power of the emerging air draft for some chosen values of other parameters. The model also shows the proportion in which absorbed solar energy is divided into different forms, and hence predicts the dependence of kinetic of emerging air draft upon dimensions of the chimney and properties of materials used. Further, it is shown that external winds enhance the kinetic power of the emerging air. Thus ISC can also harness the wind energy, available at the top of the mountain.

  13. Solar dynamic power system definition study

    Science.gov (United States)

    Wallin, Wayne E.; Friefeld, Jerry M.

    1988-01-01

    The solar dynamic power system design and analysis study compared Brayton, alkali-metal Rankine, and free-piston Stirling cycles with silicon planar and GaAs concentrator photovoltaic power systems for application to missions beyond the Phase 2 Space Station level of technology for all power systems. Conceptual designs for Brayton and Stirling power systems were developed for 35 kWe and 7 kWe power levels. All power systems were designed for 7-year end-of-life conditions in low Earth orbit. LiF was selected for thermal energy storage for the solar dynamic systems. Results indicate that the Stirling cycle systems have the highest performance (lowest weight and area) followed by the Brayton cycle, with photovoltaic systems considerably lower in performance. For example, based on the performance assumptions used, the planar silicon power system weight was 55 to 75 percent higher than for the Stirling system. A technology program was developed to address areas wherein significant performance improvements could be realized relative to the current state-of-the-art as represented by Space Station. In addition, a preliminary evaluation of hardenability potential found that solar dynamic systems can be hardened beyond the hardness inherent in the conceptual designs of this study.

  14. Polar ionospheric responses to solar wind IMF changes

    Directory of Open Access Journals (Sweden)

    Y. Zhang

    Full Text Available Auroral and airglow emissions over Eureka (89° CGM during the 1997-98 winter show striking variations in relation to solar wind IMF changes. The period January 19 to 22, 1998, was chosen for detailed study, as the IMF was particularly strong and variable. During most of the period, Bz was northward and polar arcs were observed. Several overpasses by DMSP satellites during the four day period provided a clear picture of the particle precipitation producing the polar arcs. The spectral character of these events indicated excitation by electrons of average energy 300 to 500 eV. Only occasionally were electrons of average energy up to ~1 keV observed and these appeared transitory from the ground optical data. It is noted that polar arcs appear after sudden changes in IMF By, suggesting IMF control over arc initiation. When By is positive there is arc motion from dawn to dusk, while By is negative the motion is consistently dusk to dawn. F-region (anti-sunward convections were monitored through the period from 630.0 nm emissions. The convection speed was low (100-150 m/s when Bz was northward but increased to 500 m/s after Bz turned southward on January 20.

    Key words: Atmospheric composition and structure (airglow and aurora - Ionosphere (particle precipitation - Magnetospheric Physics (polar cap phenomena

  15. Solar Power Beaming: From Space to Earth

    Energy Technology Data Exchange (ETDEWEB)

    Rubenchik, A M; Parker, J M; Beach, R J; Yamamoto, R M

    2009-04-14

    Harvesting solar energy in space and power beaming the collected energy to a receiver station on Earth is a very attractive way to help solve mankind's current energy and environmental problems. However, the colossal and expensive 'first step' required in achieving this goal has to-date stifled its initiation. In this paper, we will demonstrate that recent advance advances in laser and optical technology now make it possible to deploy a space-based system capable of delivering 1 MW of energy to a terrestrial receiver station, via a single unmanned commercial launch into Low Earth Orbit (LEO). Figure 1 depicts the overall concept of our solar power beaming system, showing a large solar collector in space, beaming a coherent laser beam to a receiving station on Earth. We will describe all major subsystems and provide technical and economic discussion to support our conclusions.

  16. Short-Term Solar Collector Power Forecasting

    DEFF Research Database (Denmark)

    Bacher, Peder; Madsen, Henrik; Perers, Bengt

    2011-01-01

    This paper describes a new approach to online forecasting of power output from solar thermal collectors. The method is suited for online forecasting in many applications and in this paper it is applied to predict hourly values of power from a standard single glazed large area flat plate collector....... The method is applied for horizons of up to 42 hours. Solar heating systems naturally come with a hot water tank, which can be utilized for energy storage also for other energy sources. Thereby such systems can become an important part of energy systems with a large share of uncontrollable energy sources......-adaptive linear models. The approach is similar to the one by Bacher et al. (2009), but contains additional effects due to differences between solar thermal collectors and photovoltaics. Numerical weather predictions provided by Danish Meteorological Institute are used as input. The applied models adapt over time...

  17. Simulation of hybrid solar power plants

    Science.gov (United States)

    Dieckmann, Simon; Dersch, Jürgen

    2017-06-01

    Hybrid solar power plants have the potential to combine advantages of two different technologies at the cost of increased complexity. The present paper shows the potential of the software greenius for the techno-economic evaluation of hybrid solar power plants and discusses two exemplary scenarios. Depreciated Concentrated Solar Power (CSP) plants based on trough technology can be retrofitted with solar towers in order to reach higher steam cycle temperatures and hence efficiencies. Compared to a newly built tower plant the hybridization of a depreciated trough plant causes about 30% lower LCOE reaching 104 /MWh. The second hybrid scenario combines cost-efficient photovoltaics with dispatchable CSP technology. This hybrid plant offers very high capacity factors up to 69% based on 100% load from 8am to 11pm. The LCOE of the hybrid plant are only slightly lower (174 vs. 186 /MWh) compared to the pure CSP plant because the capital expenditure for thermal storage and power block remains the same while the electricity output is much lower.

  18. Solar-powered hot-air system

    Science.gov (United States)

    1979-01-01

    Solar-powered air heater supplies part or all of space heating requirements of residential or commercial buildings and is interfaced with air to water heat exchanger to heat domestic hot water. System has potential application in drying agricultural products such as cotton, lumber, corn, grains, and peanuts.

  19. Solar-Powered Cooler and Heater for an Automobile Interior

    Science.gov (United States)

    Howard, Richard T.

    2006-01-01

    The apparatus would include a solar photovoltaic panel mounted on the roof and a panellike assembly mounted in a window opening. The window-mounted assembly would include a stack of thermoelectric devices sandwiched between two heat sinks. A fan would circulate interior air over one heat sink. Another fan would circulate exterior air over the other heat sink. The fans and the thermoelectric devices would be powered by the solar photovoltaic panel. By means of a double-pole, double-throw switch, the panel voltage fed to the thermoelectric stack would be set to the desired polarity: For cooling operation, the chosen polarity would be one in which the thermoelectric devices transport heat from the inside heat sink to the outside one; for heating operation, the opposite polarity would be chosen. Because thermoelectric devices are more efficient in heating than in cooling, this apparatus would be more effective as a heater than as a cooler. However, if the apparatus were to include means to circulate air between the outside and the inside without opening the windows, then its effectiveness as a cooler in a hot, sunny location would be increased.

  20. New Markets for Solar Photovoltaic Power Systems

    Science.gov (United States)

    Thomas, Chacko; Jennings, Philip; Singh, Dilawar

    2007-10-01

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

  1. Lightweight Solar Power for Small Satellites

    Science.gov (United States)

    Nabors, Sammy A.

    2015-01-01

    The innovation targets small satellites or CubeSats for which conventional deployable arrays are not feasible due to their size, weight and complexity. This novel solar cell array includes a thin and flexible photovoltaic cell applied to an inflatable structure to create a high surface area array for collecting solar energy in a lightweight, simple and deployable structure. The inflatable array, with its high functional surface area, eliminates the need and the mechanisms required to point the system toward the sun. The power density achievable in these small arrays is similar to that of conventional high-power deployable/pointable arrays used on large satellites or space vehicles. Although inflatable solar arrays have been previously considered by others, the arrays involved the use of traditional rigid solar cells. Researchers are currently working with thin film photovoltaics from various suppliers so that the NASA innovation is not limited to any particular solar cell technology. NASA has built prototypes and tested functionality before and after inflation. As shown in the current-voltage currents below, deployment does not damage the cell performance.

  2. Polarized Light from the Sun: Unification of the Corona and Analysis of the Second Solar Spectrum — Further Implications of a Liquid Metallic Hydrogen Solar Model

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2015-07-01

    in the chromosphere. The prevalence of polarized signals from the Rare Earth metals, a chemically unique group of the periodic table, provides powerful evidence, based on the “Second Solar Spectrum”, that chemical reactions and coordination are taking place in the atmosphere of the Sun. This concept is also supported by the polarized signal from lithium, an element previously hypothesized to assist in stabilizing metallic hydrogen structures. The possibility that some atoms are coordinated with CHS implies that the relative abundance of elements cannot be simply ascertained through the analysis of emission or absorption lines in the solar atmosphere.

  3. Development of concentrated solar power and conventional power plant hybrids

    OpenAIRE

    Suojanen, Suvi

    2016-01-01

    CSP hybrids are one of the possible technical solutions in order to increase the share of renewable energy and decrease greenhouse gas emission levels as well as fuel consump-tion. The main objectives of the thesis are to research state-of-the-art technologies in concentrated solar power (CSP) and conventional power plants, to comprehensively study the possible integration options and to develop one CSP hybrid configuration by using Advanced Process Simulator (Apros), which is a dynamic model...

  4. Concentrating Solar Power Program Review 2013 (Book) (Revised)

    Energy Technology Data Exchange (ETDEWEB)

    2013-06-01

    This U.S. Department of Energy (DOE) Concentrating Solar Power Program Review Meeting booklet will be provided to attendees at the Concentrating Solar Power Review Meeting in Phoenix, Arizona on April 23-25, 2013.

  5. Backscatter, anisotropy, and polarization of solar hard X-rays

    International Nuclear Information System (INIS)

    Bai, T.; Ramaty, R.

    1978-01-01

    Hard X-rays incident upon the photosphere with energies > or approx. =15 keV have high probabilities of backscatter due to Compton collisions with electrons. This effect has a strong influence on the spectrum, intensity, and polarization of solar hard X-rays - especially for anisotropic models in which the primary X-rays are emitted predominantly toward the photosphere. We have carried out a detailed study of X-ray backscatter, and we have investigated the interrelated problems of anisotropy, polarization, center-to-limb variation of the X-ray spectrum, and Compton backscatter in a coherent fashion. The results of this study are compared with observational data. Because of the large contribution from backscatter, for an anisotropic primary X-ray source which is due to bremsstrahlung of accelerated electrons moving predominantly down toward the photosphere, the observed X-ray flux around 30 keV does not depend significantly on the position of flare on the Sun. For such an anisotropic source, the X-ray spectrum observed in the 15-50 keV range becomes steeper with the increasing heliocentric angle of the flare. These results are compatible with the data. The degree of polarization of the sum of the primary and reflected X-rays with energies between about 15 and 30 keV can be very large for anisotropic primary X-ray sources, but it is less than about 4% for isotropic sources. We also discuss the characteristics of the brightness distribution of the X-ray albedo patch created by the Compton backscatter. The height and anisotropy of the primary hard X-ray source might be inferred from the study of the albedo patch

  6. Polar mesosphere summer echoes during the July 2000 solar protonevent

    Directory of Open Access Journals (Sweden)

    V. Barabash

    2004-03-01

    Full Text Available The influence of the solar proton event (SPE 14–16 July 2000 on Polar Mesosphere Summer Echoes (PMSE is examined. PMSE were observed by the Esrange VHF MST Radar (ESRAD at 67°53'N, 21°06'E. The 30MHz Imaging Riometer for Ionospheric Studies IRIS in Kilpisjärvi (69°30'N, 20°47'E registered cosmic radio noise absorption caused by ionisation changes in response to the energetic particle precipitation. An energy deposition/ion-chemical model was used to estimate the density of free electrons and ions in the upper atmosphere. Particle collision frequencies were calculated from the MSISE-90 model. Electric fields were calculated using conductivities from the model and measured magnetic disturbances. The electric field reached a maximum of 91mV/m during the most intensive period of the geomagnetic storm accompanying the SPE. The temperature increase due to Joule and particle heating was calculated, taking into account radiative cooling. The temperature increase at PMSE heights was found to be very small. The observed PMSE were rather intensive and extended over the 80–90km height interval. PMSE almost disappeared above 86km at the time of greatest Joule heating on 15 July 2000. Neither ionisation changes, nor Joule/particle heating can explain the PMSE reduction. Transport effects due to the strong electric field are a more likely explanation. Key words. Meteorology and atmospheric dynamics (middle atmospheric dynamics, ionosphere (ionospheric disturbances; solar radiation and cosmic ray effects

  7. Joint DOA and Polarization Estimation for Unequal Power Sources

    Directory of Open Access Journals (Sweden)

    Qingyuan Fang

    2015-01-01

    Full Text Available For most joint direction of arrival (DOA and polarization estimation methods, the performances of proposed methods in dealing with unequal power sources are not discussed. However, sources with unequal powers apparently exist widely in actual applications. In this study, we propose a joint DOA and polarization estimation method for unequal power sources by utilizing the invariance property of noise subspace (IPNS to the power of sources. This work extends the IPNS method to the dual polarized antenna array for joint DOA and polarization estimation. Moreover, we theoretically prove that the IPNS remains valid even when the sources are correlated. The computer simulations illustrate that the proposed method can effectively estimate the DOA and polarization parameters as the power difference between sources increases, as opposed to the polarimetric multiple signal classification (MUSIC algorithm, which suffers from degradation in resolution probability. In addition, the performances of the proposed method are provided, as well the Cramer Rao Bound (CRB, which show approximate performance as the polarimetric MUSIC algorithm.

  8. Optical study of solar tower power plants

    International Nuclear Information System (INIS)

    Eddhibi, F; Amara, M Ben; Balghouthi, M; Guizani, A

    2015-01-01

    The central receiver technology for electricity generation consists of concentrating solar radiation coming from the solar tracker field into a central receiver surface located on the top of the tower. The heliostat field is constituted of a big number of reflective mirrors; each heliostat tracks the sun individually and reflects the sunlight to a focal point. Therefore, the heliostat should be positioned with high precision in order to minimize optical losses. In the current work, a mathematical model for the analysis of the optical efficiency of solar tower field power plant is proposed. The impact of the different factors which influence the optical efficiency is analyzed. These parameters are mainly, the shading and blocking losses, the cosine effect, the atmospheric attenuation and the spillage losses. A new method for the calculation of blocking and shadowing efficiency is introduced and validated by open literature

  9. Renewable Energy Essentials: Concentrating Solar Thermal Power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

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

  10. Solids-based concentrated solar power receiver

    Energy Technology Data Exchange (ETDEWEB)

    None

    2018-04-10

    A concentrated solar power (CSP) system includes channels arranged to convey a flowing solids medium descending under gravity. The channels form a light-absorbing surface configured to absorb solar flux from a heliostat field. The channels may be independently supported, for example by suspension, and gaps between the channels are sized to accommodate thermal expansion. The light absorbing surface may be sloped so that the inside surfaces of the channels proximate to the light absorbing surface define downward-slanting channel floors, and the flowing solids medium flows along these floors. Baffles may be disposed inside the channels and oriented across the direction of descent of the flowing solids medium. The channels may include wedge-shaped walls forming the light-absorbing surface and defining multiple-reflection light paths for solar flux from the heliostat field incident on the light-absorbing surface.

  11. Experimental investigation of solar powered diaphragm and helical pumps

    Science.gov (United States)

    For several years, many types of solar powered water pumping systems were evaluated, and in this paper, diaphragm and helical solar photovoltaic (PV) powered water pumping systems are discussed. Data were collected on diaphragm and helical pumps which were powered by different solar PV arrays at mul...

  12. Vertical and Horizontal Polarization Observations of Slowly Varying Solar Emissions from Operational Swiss Weather Radars

    Directory of Open Access Journals (Sweden)

    Marco Gabella

    2014-12-01

    Full Text Available The electromagnetic power that arrives from the Sun in the C-band has been used to check the quality of the polarimetric, Doppler weather radar network that has recently been installed in Switzerland. The operational monitoring of this network is based on the analysis of Sun signals in the polar volume data produced during the MeteoSwiss scan program. It relies on a method that has been developed to: (1 determine electromagnetic antenna pointing; (2 monitor receiver stability; and (3 assess the differential reflectivity offset. Most of the results from such a method had been derived using data acquired in 2008, which was a period of quiet solar flux activity. Here, it has been applied, in simplified form, to the currently active Sun period. This note describes the results that have been obtained recently thanks to an inter-comparison of three polarimetric operational radars and the Sun’s reference signal observed in Canada in the S-band by the Dominion Radio Astrophysical Observatory (DRAO. The focus is on relative calibration: horizontal and vertical polarization are evaluated versus the DRAO reference and mutually compared. All six radar receivers (three systems, two polarizations are able to capture and describe the monthly variability of the microwave signal emitted by the Sun. It can be concluded that even this simplified form of the method has the potential to routinely monitor dual-polarization weather radar networks during periods of intense Sun activity.

  13. Solar polar magnetic field dependency of geomagnetic activity semiannual variation indicated in the Aa index

    Science.gov (United States)

    Oh, Suyeon; Yi, Yu

    2018-01-01

    Three major hypotheses have been proposed to explain the well-known semiannual variation of geomagnetic activity, maxima at equinoxes and minima at solstices. This study examined whether the seasonal variation of equinoctial geomagnetic activity is different in periods of opposite solar magnetic polarity in order to understand the contribution of the interplanetary magnetic field (IMF) in the Sun-Earth connection. Solar magnetic polarity is parallel to the Earth's polarity in solar minimum years of odd/even cycles but antiparallel in solar minimum years of even/odd cycles. The daily mean of the aa, Aa indices during each solar minimum was compared for periods when the solar magnetic polarity remained in opposite dipole conditions. The Aa index values were used for each of the three years surrounding the solar minimum years of the 14 solar cycles recorded since 1856. The Aa index reflects seasonal variation in geomagnetic activity, which is greater at the equinoxes than at the solstices. The Aa index reveals solar magnetic polarity dependency in which the geomagnetic activity is stronger in the antiparallel solar magnetic polarity condition than in the parallel one. The periodicity in semiannual variation of the Aa index is stronger in the antiparallel solar polar magnetic field period than in the parallel period. Additionally, we suggest the favorable IMF condition of the semiannual variation in geomagnetic activity. The orientation of IMF toward the Sun in spring and away from the Sun in fall mainly contributes to the semiannual variation of geomagnetic activity in both antiparallel and parallel solar minimum years.

  14. Polar mesosphere summer echoes during the July 2000 solar protonevent

    Directory of Open Access Journals (Sweden)

    V. Barabash

    2004-03-01

    Full Text Available The influence of the solar proton event (SPE 14–16 July 2000 on Polar Mesosphere Summer Echoes (PMSE is examined. PMSE were observed by the Esrange VHF MST Radar (ESRAD at 67°53'N, 21°06'E. The 30MHz Imaging Riometer for Ionospheric Studies IRIS in Kilpisjärvi (69°30'N, 20°47'E registered cosmic radio noise absorption caused by ionisation changes in response to the energetic particle precipitation. An energy deposition/ion-chemical model was used to estimate the density of free electrons and ions in the upper atmosphere. Particle collision frequencies were calculated from the MSISE-90 model. Electric fields were calculated using conductivities from the model and measured magnetic disturbances. The electric field reached a maximum of 91mV/m during the most intensive period of the geomagnetic storm accompanying the SPE. The temperature increase due to Joule and particle heating was calculated, taking into account radiative cooling. The temperature increase at PMSE heights was found to be very small.

    The observed PMSE were rather intensive and extended over the 80–90km height interval. PMSE almost disappeared above 86km at the time of greatest Joule heating on 15 July 2000. Neither ionisation changes, nor Joule/particle heating can explain the PMSE reduction. Transport effects due to the strong electric field are a more likely explanation.

    Key words. Meteorology and atmospheric dynamics (middle atmospheric dynamics, ionosphere (ionospheric disturbances; solar radiation and cosmic ray effects

  15. Polar solar panels: Arctic and Antarctic microbiomes display similar taxonomic profiles.

    Science.gov (United States)

    Tanner, Kristie; Martí, Jose Manuel; Belliure, Josabel; Fernández-Méndez, Mar; Molina-Menor, Esther; Peretó, Juli; Porcar, Manuel

    2018-02-01

    Solar panels located on high (Arctic and Antarctic) latitudes combine the harshness of the climate with that of the solar exposure. We report here that these polar solar panels are inhabited by similar microbial communities in taxonomic terms, dominated by Hymenobacter spp., Sphingomonas spp. and Ascomycota. Our results suggest that solar panels, even on high latitudes, can shape a microbial ecosystem adapted to irradiation and desiccation. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. X-Parameter Based Modelling of Polar Modulated Power Amplifiers

    DEFF Research Database (Denmark)

    Wang, Yelin; Nielsen, Troels Studsgaard; Sira, Daniel

    2013-01-01

    X-parameters are developed as an extension of S-parameters capable of modelling non-linear devices driven by large signals. They are suitable for devices having only radio frequency (RF) and DC ports. In a polar power amplifier (PA), phase and envelope of the input modulated signal are applied...... at separate ports and the envelope port is neither an RF nor a DC port. As a result, X-parameters may fail to characterise the effect of the envelope port excitation and consequently the polar PA. This study introduces a solution to the problem for a commercial polar PA. In this solution, the RF-phase path...... PA for simulations. The simulated error vector magnitude (EVM) and adjacent channel power ratio (ACPR) were compared with the measured data to validate the model. The maximum differences between the simulated and measured EVM and ACPR are less than 2% point and 3 dB, respectively....

  17. A fresh look at space solar power

    International Nuclear Information System (INIS)

    Mankins, J.C.

    1996-01-01

    Studies of systems to provide solar power from space for terrestrial use defined very large, geostationary Earth orbit (GEO) satellite concepts that--given massive initial government investments and extremely low cost space launch--might have led to power production at costs only somewhat higher than expected commercial prices. These studies of space solar power (SSP) succeeded in establishing technical feasibility. Shortly after the completion of the 1970s study, however, US funding came to an abrupt and seemingly permanent halt--in part because projected costs for the reference system were staggering: well in excess of $100B to achieve the first commercial kilowatt-hour of power. SSP has seen sporadic study and limited experimentation during the past decade (e.g., in Japan). Still, no existing SSP concept has engendered private development. New technologies now make possible concepts and approaches that suggest that SSP economic feasibility may be achievable early in the next century. In 1995, NASA's Advanced Concepts Office initiated a study taking a fresh look at innovative concepts for SSP that differ markedly from previously examined concepts, addressing innovative system architectures, markets and technologies that could radically reduce initial and operational costs. This paper will explore the issues associated with SSP and will summarize the results to date of NASA's recent fresh look at this important and increasingly timely field of space applications

  18. Solar power in South Africa; Anpfiff in Suedafrika

    Energy Technology Data Exchange (ETDEWEB)

    Ristau, Oliver

    2010-07-01

    Excellent reimbursement regulations for solar power should be enough to promote photovoltaic energy conversion in South Africa. However, public utilities are not obliged to buy solar power, and the connection of private solar systems to the public grid is a matter for negotiation. Many private investors therefore decide to instal autonomous systems. (orig.)

  19. Solar Dynamic Power System Fault Diagnosis

    Science.gov (United States)

    Momoh, James A.; Dias, Lakshman G.

    1996-01-01

    The objective of this research is to conduct various fault simulation studies for diagnosing the type and location of faults in the power distribution system. Different types of faults are simulated at different locations within the distribution system and the faulted waveforms are monitored at measurable nodes such as at the output of the DDCU's. These fault signatures are processed using feature extractors such as FFT and wavelet transforms. The extracted features are fed to a clustering based neural network for training and subsequent testing using previously unseen data. Different load models consisting of constant impedance and constant power are used for the loads. Open circuit faults and short circuit faults are studied. It is concluded from present studies that using features extracted from wavelet transforms give better success rates during ANN testing. The trained ANN's are capable of diagnosing fault types and approximate locations in the solar dynamic power distribution system.

  20. Design investigation of solar powered lasers for space applications

    Science.gov (United States)

    Taussig, R.; Bruzzone, C.; Quimby, D.; Nelson, L.; Christiansen, W.; Neice, S.; Cassady, P.; Pindroh, A.

    1979-01-01

    The feasibility of solar powered lasers for continuous operation in space power transmission was investigated. Laser power transmission in space over distances of 10 to 100 thousand kilometers appears possible. A variety of lasers was considered, including solar-powered GDLs and EDLs, and solar-pumped lasers. An indirect solar-pumped laser was investigated which uses a solar-heated black body cavity to pump the lasant. Efficiencies in the range of 10 to 20 percent are projected for these indirect optically pumped lasers.

  1. Monitoring of the solar power plants and performance ratio

    Science.gov (United States)

    Sredenšek, Klemen; Šlamberger, Jan; Štumberger, Bojan; Hadžiselimović, Miralem; Seme, Sebastijan

    2017-07-01

    This paper deals with monitoring of solar power plants. We can observe solar power plants with energy yield, monitoring or performance ratio. All these approaches of monitoring solar power plants have their advantages and disadvantages. The procedures of monitoring different solar power plants in Slovenia will be presented and evaluated in the paper. It turns out that energy yield and monitoring of solar power plants don't give enough necessary information concerning proper operation. Energy yield is the ratio between the energy produced and the nominal power of the solar power plant. Energy yield is dependent on the intensity of solar radiation and temperature. It appears that proper operation of solar power plants is best described with the performance ratio, which is the ration between the energy produced and the energy that would be produced at nominal yield. Performance ratio considers the intensity of solar radiation and/or temperature. The results show that the proper operation of the solar power plants is mostly affected by appropriate installation and orientation of solar modules.

  2. Distributed Solar Photovoltaic Power Production - Technology and Benefits

    Energy Technology Data Exchange (ETDEWEB)

    Matos, Al [PSE& G; Stuby, Rick [Petra Solar

    2011-11-02

    As part of its nationally recognized Solar 4 All program, PSE&G has partnered with Petra Solar to deploy the world’s first and largest pole attached solar project. The project, based on Petra Solar’s distributed Smart Solar solution, will create a 40 megawatt solar “virtual power plant.” In deployment as 200,000 individual grid-connected solar power producers on utility poles in PSE&G territory, Petra Solar SunWave® solutions leverage Smart Grid communications and high-tech panel-level inverters to implement a robust system with many technical benefits over traditional solar photovoltaic solutions. The program overview, deployment model, smart grid communications and enabling inverter technology and safety features will be presented, as well the future challenges of, and solutions for, solar power intermittency as photovoltaic penetration on the electric grid increases.

  3. HEMISPHERIC ASYMMETRIES IN THE POLAR SOLAR WIND OBSERVED BY ULYSSES NEAR THE MINIMA OF SOLAR CYCLES 22 AND 23

    International Nuclear Information System (INIS)

    Ebert, R. W.; Dayeh, M. A.; Desai, M. I.; McComas, D. J.; Pogorelov, N. V.

    2013-01-01

    We examined solar wind plasma and interplanetary magnetic field (IMF) observations from Ulysses' first and third orbits to study hemispheric differences in the properties of the solar wind and IMF originating from the Sun's large polar coronal holes (PCHs) during the declining and minimum phase of solar cycles 22 and 23. We identified hemispheric asymmetries in several parameters, most notably ∼15%-30% south-to-north differences in averages for the solar wind density, mass flux, dynamic pressure, and energy flux and the radial and total IMF magnitudes. These differences were driven by relatively larger, more variable solar wind density and radial IMF between ∼36°S-60°S during the declining phase of solar cycles 22 and 23. These observations indicate either a hemispheric asymmetry in the PCH output during the declining and minimum phase of solar cycles 22 and 23 with the southern hemisphere being more active than its northern counterpart, or a solar cycle effect where the PCH output in both hemispheres is enhanced during periods of higher solar activity. We also report a strong linear correlation between these solar wind and IMF parameters, including the periods of enhanced PCH output, that highlight the connection between the solar wind mass and energy output and the Sun's magnetic field. That these enhancements were not matched by similar sized variations in solar wind speed points to the mass and energy responsible for these increases being added to the solar wind while its flow was subsonic.

  4. 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

  5. Energy analysis of the solar power satellite.

    Science.gov (United States)

    Herendeen, R A; Kary, T; Rebitzer, J

    1979-08-03

    The energy requirements to build and operate the proposed Solar Power Satellite are evaluated and compared with the energy it produces. Because the technology is so speculative, uncertainty is explicitly accounted for. For a proposed 10-gigawatt satellite system, the energy ratio, defined as the electrical energy produced divided by the primary nonrenewable energy required over the lifetime of the system, is of order 2, where a ratio of 1 indicates the energy breakeven point. This is significantly below the energy ratio of today's electricity technologies such as light-water nuclear or coal-fired electric plants.

  6. Space-Based Solar Power System Architecture

    Science.gov (United States)

    2012-12-01

    winter, and day- night cycles to less than an average of 250 W/m2”; a drop of 1117 W/m2. Current terrestrial-based solar panels can, at a maximum...CA. Harris Corporation of Melbourne , FL, developed the satellites’ 22-meter L-band reflector” (Boeing Corporation, 2010b, p. 2). c. Lockheed Martin...the long- term to increased competition and risk, PowerSat has published a white paper outlining their notional first satellite. It appears to operate

  7. Modern prospects of development of branch of solar power

    Science.gov (United States)

    Luchkina, Veronika

    2017-10-01

    Advantages of solar energy for modern companies are evident already. Article describes mechanism of the solar electricity generation. Process of production of solar modules with appliance of the modern technologies of sun energy production. The branch of solar energy “green energy” become advanced in Russia and has a stable demand. Classification of investments on the different stages of construction projects of solar power plants and calculation of their economic efficiency. Studying of introduction of these technologies allows to estimate the modern prospects of development of branch of solar power.

  8. Characteristics of the Polarity Inversion Line and Solar Flare Forecasts

    Science.gov (United States)

    Sadykov, Viacheslav M.; Kosovichev, Alexander G.

    2017-08-01

    Studying connection between solar flares and properties of magnetic field in active regions is very important for understanding the flare physics and developing space weather forecasts. In this work, we analyze relationship between the flare X-ray peak flux from the GOES satellite, and characteristics of the line-of-sight (LOS) magnetograms obtained by the SDO/HMI instrument during the period of April, 2010 - June, 2016. We try to answer two questions: 1) What characteristics of the LOS magnetic field are most important for the flare initiation and magnitude? 2) Is it possible to construct a reliable forecast of ≥ M1.0 and ≥ X1.0 class flares based only on the LOS magnetic field characteristics? To answer these questions, we apply a Polarity Inversion Line (PIL) detection algorithm, and derive various properties of the PIL and the corresponding Active Regions (AR). The importance of these properties for flare forecasting is determined by their ability to separate flaring cases from non-flaring, and their Fisher ranking score. It is found that the PIL characteristics are of special importance for the forecasts of both ≥ M1.0 and ≥ X1.0 flares, while the global AR characteristics become comparably discriminative only for ≥ X1.0 flares. We use the Support Vector Machine (SVM) classifier and train it on the six characteristics of the most importance for each case. The obtained True Skill Statistics (TSS) values of 0.70 for ≥ M1.0 flares and 0.64 for ≥ X1.0 flares are better than the currently-known expert-based predictions. Therefore, the results confirm the importance of the LOS magnetic field data and, in particular, the PIL region characteristics for flare forecasts.

  9. MgII Linear Polarization Measurements Using the MSFC Solar Ultraviolet Magnetograph Sounding Rocket

    Science.gov (United States)

    West, Edward; Cirtain, Jonathan; Kobayashi, Ken; Davis, John; Gary, Allen

    2011-01-01

    This paper will describe the Marshall Space Flight Center's Solar Ultraviolet Magnetograph Investigation (SUMI) sounding rocket program, with emphasis on the polarization characteristics of the VUV optics and their spectral, spatial and polarization resolution. SUMI's first flight (7/30/2010) met all of its mission success criteria and this paper will describe the data that was acquired with emphasis on the MgII linear polarization measurements.

  10. Solar Powered Reverse Trash Vendo Machine

    Directory of Open Access Journals (Sweden)

    Alexis John M. Rubio

    2016-05-01

    Full Text Available –The study was conducted with the purpose of developing a Solar Powered Reverse Trash Vendo Machine that aims to encourage people to engage in recycling and to diminish the practice of improper waste disposal in thePhilippines. The device used a Gizduino X ATMega 1281 as its main processing module along with a Gizduino 644 microcontroller board, anda GSM Shield module for communication. Arduino1.6 IDE is used to program the Gizduinoboards. The device is powered by a 15V rechargeable battery, which is charged by a solar panel retrofitted at the roof of the device, this is to promote energy conservation, and green engineering principles in the development of the study.The device can process empty plastic bottles (500ml. max with a base diameter of 3.5 inches, and aluminium cans. These recyclable materials are placed inside the machine and is scanned, then crushed and placed in a bin. An inductive sensor is used to detect either the material is a plastic bottle or an aluminium can. To compensate the user for recycling, an equivalent monetary value will be dispensed. The owner of the device can check the status of the coin dispenser and bins through an Android messaging application developed using the Eclipse IDE and the Java programming language, and when a certain limit is reached by the coin dispenser or the trash bins, an automatic text message notification will be sent to the owner.

  11. 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)

  12. High-speed solar wind streams and polar mesosphere winter echoes at Troll, Antarctica

    Directory of Open Access Journals (Sweden)

    S. Kirkwood

    2015-06-01

    Full Text Available A small, 54 MHz wind-profiler radar, MARA, was operated at Troll, Antarctica (72° S, 2.5° E, continuously from November 2011 to January 2014, covering two complete Antarctic winters. Despite very low power, MARA observed echoes from heights of 55–80 km (polar mesosphere winter echoes, PMWE on 60% of all winter days (from March to October. This contrasts with previous reports from radars at high northern latitudes, where PWME have been reported only by very high power radars or during rare periods of unusually high electron density at PMWE heights, such as during solar proton events. Analysis shows that PWME at Troll were not related to solar proton events but were often closely related to the arrival of high-speed solar wind streams (HSS at the Earth, with PWME appearing at heights as low as 56 km and persisting for up to 15 days following HSS arrival. This demonstrates that HSS effects penetrate directly to below 60 km height in the polar atmosphere. Using local observations of cosmic-noise absorption (CNA, a theoretical ionization/ion-chemistry model and a statistical model of precipitating energetic electrons associated with HSS, the electron density conditions during the HSS events are estimated. We find that PMWE detectability cannot be explained by these variations in electron density and molecular-ion chemistry alone. PWME become detectable at different thresholds depending on solar illumination and height. In darkness, PWME are detected only when the modelled electron density is above a threshold of about 1000 cm−3, and only above 75 km height, where negative ions are few. In daylight, the electron density threshold falls by at least 2 orders of magnitude and PWME are found primarily below 75 km height, even in conditions when a large proportion of negative ions is expected. There is also a strong dawn–dusk asymmetry with PWME detected very rarely during morning twilight but often during evening twilight. This behaviour cannot be

  13. High-speed solar wind streams and polar mesosphere winter echoes at Troll, Antarctica

    Energy Technology Data Exchange (ETDEWEB)

    Kirkwood, S.; Belova, E. [Swedish Institute of Space Physics, Kiruna (Sweden). Polar Atmospheric Research; Osepian, A. [Polar Geophysical Institute, Murmansk (Russian Federation); Lee, Y.S. [Korea Astronomy and Space Science Institute, Daejeon (Korea, Republic of)

    2015-10-01

    A small, 54 MHz wind-profiler radar, MARA, was operated at Troll, Antarctica (72 S, 2.5 E), continuously from November 2011 to January 2014, covering two complete Antarctic winters. Despite very low power, MARA observed echoes from heights of 55-80 km (polar mesosphere winter echoes, PMWE) on 60% of all winter days (from March to October). This contrasts with previous reports from radars at high northern latitudes, where PWME have been reported only by very high power radars or during rare periods of unusually high electron density at PMWE heights, such as during solar proton events. Analysis shows that PWME at Troll were not related to solar proton events but were often closely related to the arrival of high-speed solar wind streams (HSS) at the Earth, with PWME appearing at heights as low as 56 km and persisting for up to 15 days following HSS arrival. This demonstrates that HSS effects penetrate directly to below 60 km height in the polar atmosphere. Using local observations of cosmic-noise absorption (CNA), a theoretical ionization/ion-chemistry model and a statistical model of precipitating energetic electrons associated with HSS, the electron density conditions during the HSS events are estimated. We find that PMWE detectability cannot be explained by these variations in electron density and molecular-ion chemistry alone. PWME become detectable at different thresholds depending on solar illumination and height. In darkness, PWME are detected only when the modelled electron density is above a threshold of about 1000 cm{sup -3}, and only above 75 km height, where negative ions are few. In daylight, the electron density threshold falls by at least 2 orders of magnitude and PWME are found primarily below 75 km height, even in conditions when a large proportion of negative ions is expected. There is also a strong dawn-dusk asymmetry with PWME detected very rarely during morning twilight but often during evening twilight. This behaviour cannot be explained if PMWE

  14. The place of solar power: an economic analysis of concentrated and distributed solar power

    Science.gov (United States)

    2012-01-01

    Background This paper examines the cost and benefits, both financial and environmental, of two leading forms of solar power generation, grid-tied photovoltaic cells and Dish Stirling Systems, using conventional carbon-based fuel as a benchmark. Methods First we define how these solar technologies will be implemented and why. Then we delineate a model city and its characteristics, which will be used to test the two methods of solar-powered electric distribution. Then we set the constraining assumptions for each technology, which serve as parameters for our calculations. Finally, we calculate the present value of the total cost of conventional energy needed to power our model city and use this as a benchmark when analyzing both solar models’ benefits and costs. Results The preeminent form of distributed electricity generation, grid-tied photovoltaic cells under net-metering, allow individual homeowners a degree of electric self-sufficiency while often turning a profit. However, substantial subsidies are required to make the investment sensible. Meanwhile, large dish Stirling engine installations have a significantly higher potential rate of return, but face a number of pragmatic limitations. Conclusions This paper concludes that both technologies are a sensible investment for consumers, but given that the dish Stirling consumer receives 6.37 dollars per watt while the home photovoltaic system consumer receives between 0.9 and 1.70 dollars per watt, the former appears to be a superior option. Despite the large investment, this paper deduces that it is far more feasible to get few strong investors to develop a solar farm of this magnitude, than to get 150,000 households to install photovoltaic arrays in their roofs. Potential implications of the solar farm construction include an environmental impact given the size of land require for this endeavour. However, the positive aspects, which include a large CO2 emission reduction aggregated over the lifespan of the farm

  15. The place of solar power: an economic analysis of concentrated and distributed solar power.

    Science.gov (United States)

    Banoni, Vanessa Arellano; Arnone, Aldo; Fondeur, Maria; Hodge, Annabel; Offner, J Patrick; Phillips, Jordan K

    2012-04-23

    This paper examines the cost and benefits, both financial and environmental, of two leading forms of solar power generation, grid-tied photovoltaic cells and Dish Stirling Systems, using conventional carbon-based fuel as a benchmark. First we define how these solar technologies will be implemented and why. Then we delineate a model city and its characteristics, which will be used to test the two methods of solar-powered electric distribution. Then we set the constraining assumptions for each technology, which serve as parameters for our calculations. Finally, we calculate the present value of the total cost of conventional energy needed to power our model city and use this as a benchmark when analyzing both solar models' benefits and costs. The preeminent form of distributed electricity generation, grid-tied photovoltaic cells under net-metering, allow individual homeowners a degree of electric self-sufficiency while often turning a profit. However, substantial subsidies are required to make the investment sensible. Meanwhile, large dish Stirling engine installations have a significantly higher potential rate of return, but face a number of pragmatic limitations. This paper concludes that both technologies are a sensible investment for consumers, but given that the dish Stirling consumer receives 6.37 dollars per watt while the home photovoltaic system consumer receives between 0.9 and 1.70 dollars per watt, the former appears to be a superior option. Despite the large investment, this paper deduces that it is far more feasible to get few strong investors to develop a solar farm of this magnitude, than to get 150,000 households to install photovoltaic arrays in their roofs. Potential implications of the solar farm construction include an environmental impact given the size of land require for this endeavour. However, the positive aspects, which include a large CO2 emission reduction aggregated over the lifespan of the farm, outweigh any minor concerns or potential

  16. The place of solar power: an economic analysis of concentrated and distributed solar power

    Directory of Open Access Journals (Sweden)

    Banoni Vanessa

    2012-04-01

    Full Text Available Abstract Background This paper examines the cost and benefits, both financial and environmental, of two leading forms of solar power generation, grid-tied photovoltaic cells and Dish Stirling Systems, using conventional carbon-based fuel as a benchmark. Methods First we define how these solar technologies will be implemented and why. Then we delineate a model city and its characteristics, which will be used to test the two methods of solar-powered electric distribution. Then we set the constraining assumptions for each technology, which serve as parameters for our calculations. Finally, we calculate the present value of the total cost of conventional energy needed to power our model city and use this as a benchmark when analyzing both solar models’ benefits and costs. Results The preeminent form of distributed electricity generation, grid-tied photovoltaic cells under net-metering, allow individual homeowners a degree of electric self-sufficiency while often turning a profit. However, substantial subsidies are required to make the investment sensible. Meanwhile, large dish Stirling engine installations have a significantly higher potential rate of return, but face a number of pragmatic limitations. Conclusions This paper concludes that both technologies are a sensible investment for consumers, but given that the dish Stirling consumer receives 6.37 dollars per watt while the home photovoltaic system consumer receives between 0.9 and 1.70 dollars per watt, the former appears to be a superior option. Despite the large investment, this paper deduces that it is far more feasible to get few strong investors to develop a solar farm of this magnitude, than to get 150,000 households to install photovoltaic arrays in their roofs. Potential implications of the solar farm construction include an environmental impact given the size of land require for this endeavour. However, the positive aspects, which include a large CO2 emission reduction aggregated

  17. Polarization Observations of the Total Solar Eclipse of August 21, 2017

    Science.gov (United States)

    Burkepile, J.; Boll, A.; Casini, R.; de Toma, G.; Elmore, D. F.; Gibson, K. L.; Judge, P. G.; Mitchell, A. M.; Penn, M.; Sewell, S. D.; Tomczyk, S.; Yanamandra-Fisher, P. A.

    2017-12-01

    A total solar eclipse offers ideal sky conditions for viewing the solar corona. Light from the corona is composed of three components: the E-corona, made up of spectral emission lines produced by ionized elements in the corona; the K-corona, produced by photospheric light that is Thomson scattered by coronal electrons; and the F-corona, produced by sunlight scattered from dust particles in the near Sun environment and in interplanetary space. Polarized white light observations of the corona provide a way of isolating the K-corona to determine its structure, brightness, and density. This work focuses on broadband white light polarization observations of the corona during the upcoming solar eclipse from three different instruments. We compare coronal polarization brightness observations of the August 21, 2017 total solar eclipse from the NCAR/High Altitude Observatory (HAO) Rosetta Stone experiment using the 4-D Technology PolarCam camera with the two Citizen PACA_CATE17Pol telescopes that will acquire linear polarization observations of the eclipse and the NCAR/HAO K-Cor white light coronagraph observations from the Mauna Loa Solar Observatory in Hawaii. This comparison includes a discussion of the cross-calibration of the different instruments and reports the results of the coronal polarization brightness and electron density of the corona. These observations will be compared with results from previous coronal measurements taken at different phases of the solar cycle. In addition, we report on the performance of the three different polarimeters. The 4-D PolarCam uses a linear polarizer array, PACA_CATE17Pol uses a nematic liquid crystal retarder in a single beam configuration and K-Cor uses a pair of ferroelectric liquid crystal retarders in a dual-beam configuration. The use of the 4-D PolarCam camera in the Rosetta Stone experiment is to demonstrate the technology for acquiring high cadence polarization measurements. The Rosetta Stone experiment is funded through

  18. The Contribution of Solar Power Funding for Online Content ...

    African Journals Online (AJOL)

    The Contribution of Solar Power Funding for Online Content Accessibility and Sustainability of Blended Learning in Rural Africa: The Tanzania Perspective. ... Despite these appealing features, penetration of solar electricity in remote and rural areas in Tanzania is limited by high initial cost of building a stand-alone solar ...

  19. THE HANLE AND ZEEMAN POLARIZATION SIGNALS OF THE SOLAR Ca II 8542 Å LINE

    Energy Technology Data Exchange (ETDEWEB)

    Štěpán, Jiri [Astronomical Institute ASCR, Fričova 298, 251 65 Ondřejov (Czech Republic); Bueno, Javier Trujillo [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain)

    2016-07-20

    We highlight the main results of a three-dimensional (3D) multilevel radiative transfer investigation about the solar disk-center polarization of the Ca ii 8542 Å line. First, through the use of a 3D model of the solar atmosphere, we investigate the linear polarization that occurs due to the atomic level polarization produced by the absorption and scattering of anisotropic radiation, taking into account the symmetry-breaking effects caused by its thermal, dynamic, and magnetic structure. Second, we study the contribution of the Zeeman effect to the linear and circular polarization. Finally, we show examples of the Stokes profiles produced by the joint action of the atomic level polarization and the Hanle and Zeeman effects. We find that the Zeeman effect tends to dominate the linear polarization signals only in the localized patches of opposite magnetic polarity, where the magnetic field is relatively strong and slightly inclined; outside such very localized patches, the linear polarization is often dominated by the contribution of atomic level polarization. We demonstrate that a correct modeling of this last contribution requires taking into account the symmetry-breaking effects caused by the thermal, dynamic, and magnetic structure of the solar atmosphere, and that in the 3D model used the Hanle effect in forward-scattering geometry (disk-center observation) mainly reduces the polarization corresponding to the zero-field case. We emphasize that, in general, a reliable modeling of the linear polarization in the Ca ii 8542 Å line requires taking into account the joint action of atomic level polarization and the Hanle and Zeeman effects.

  20. Concentrating Solar Power Gen3 Demonstration Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    Mehos, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Turchi, Craig [National Renewable Energy Lab. (NREL), Golden, CO (United States); Vidal, Judith [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wagner, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ma, Zhiwen [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ho, Clifford [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kolb, William [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Andraka, Charles [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Kruizenga, Alan [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2017-01-01

    Today's power-tower concentrating solar power (CSP) technology exists in large part as a result of Department of Energy (DOE) and utility industry funding of demonstration systems in the 1980s and 1990s. Today's most advanced towers are integrated with molten-salt thermal energy storage, delivering thermal energy at 565 degrees C for integration with conventional steam-Rankine cycles. The supercritical carbon dioxide power cycle has been identified as a likely successor to the steam-Rankine power cycle due to its potential for high efficiency when operating at elevated temperatures of 700 degrees C or greater. Over the course of the SunShot Initiative, DOE has supported a number of technology pathways that can operate efficiently at these temperatures and that hold promise to be reliable and cost effective. Three pathways - molten salt, particle, and gaseous - were selected for further investigation based on a two-day workshop held in August of 2016. The information contained in this roadmap identifies research and development challenges and lays out recommended research activities for each of the three pathways. DOE foresees that by successfully addressing the challenges identified in this roadmap, one or more technology pathways will be positioned for demonstration and subsequent commercialization within the next ten years. Based on current knowledge of the three power tower technologies, all three have the potential to achieve the SunShot goal of 6 cents/kilowatt-hour. Further development, modeling, and testing are now required to bring one or more of the technologies to a stage where integrated system tests and pilot demonstrations are feasible.

  1. Analysis of a solar powered absorption system

    International Nuclear Information System (INIS)

    Said, S.A.M.; El-Shaarawi, M.A.I.; Siddiqui, M.U.

    2015-01-01

    Highlights: • Conventional absorption system modified to increase COP. • Results indicated increase of 10% in COP due to dephlegmator heat recovery. • Results indicated increase of 8% in COP due to refrigerant storage unit. • Results indicated increase of 18% in COP due to combined effect of modifications. • Simulation results indicated a very good agreement with the measured results. - Abstract: Today, fossil fuel is the primary extensively used source of energy. However, its negative impact on the environment have forced the energy research continuity to seriously consider renewable sources of energy. Solar energy, in particular, has been the main focus in this regard because it is a source of clean energy and naturally available. This study presents the design and analysis of a solar powered absorption refrigeration system modified to increase its coefficient of performance (COP). The modifications include recovering of waste heat from a dephlegmator and utilization of a refrigerant storage unit. The simulation results indicate an increase of 10% in the COP of the conventional design using dephlegmator heat recovery and an increase of 8% in the COP of the conventional design due to the use of a refrigerant storage. The analysis for the combined effect of modifications indicates an increase of 18% in the COP compared to conventional design. Calculated values of coefficient of performance indicate a very good agreement with the ones obtained based on measurement

  2. Solar Power Station Output Inverter Control Design

    Directory of Open Access Journals (Sweden)

    J. Bauer

    2011-04-01

    Full Text Available The photovoltaic applications spreads in these days fast, therefore they also undergo great development. Because the amount of the energy obtained from the panel depends on the surrounding conditions, as intensity of the sun exposure or the temperature of the solar array, the converter must be connected to the panel output. The Solar system equipped with inverter can supply small loads like notebooks, mobile chargers etc. in the places where the supplying network is not present. Or the system can be used as a generator and it shall deliver energy to the supply network. Each type of the application has different requirements on the converter and its control algorithm. But for all of them the one thing is common – the maximal efficiency. The paper focuses on design and simulation of the low power inverter that acts as output part of the whole converter. In the paper the design of the control algorithm of the inverter for both types of inverter application – for islanding mode and for operation on the supply grid – is discussed. Attention is also paid to the design of the output filter that should reduce negative side effects of the converter on the supply network.

  3. Energy parameter estimation in solar powered wireless sensor networks

    KAUST Repository

    Mousa, Mustafa

    2014-02-24

    The operation of solar powered wireless sensor networks is associated with numerous challenges. One of the main challenges is the high variability of solar power input and battery capacity, due to factors such as weather, humidity, dust and temperature. In this article, we propose a set of tools that can be implemented onboard high power wireless sensor networks to estimate the battery condition and capacity as well as solar power availability. These parameters are very important to optimize sensing and communications operations and maximize the reliability of the complete system. Experimental results show that the performance of typical Lithium Ion batteries severely degrades outdoors in a matter of weeks or months, and that the availability of solar energy in an urban solar powered wireless sensor network is highly variable, which underlines the need for such power and energy estimation algorithms.

  4. Beam-Forming Concentrating Solar Thermal Array Power Systems

    Science.gov (United States)

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

    2016-01-01

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

  5. Solar Power Augmented Electrolysis Module for Energy Storage

    Data.gov (United States)

    National Aeronautics and Space Administration — Integrating solar photovoltaic power with regenerative fuel cell systems for energy storage can often be very complex and costly. It usually requires complex power...

  6. Solar Powering Your Community: A Guide for Local Governments (Book)

    Energy Technology Data Exchange (ETDEWEB)

    None

    2011-01-01

    DOE designed this guide—Solar Powering Your Community: A Guide for Local Governments—to assist local government officials and stakeholders in designing and implementing strategic local solar plans. The 2011 edition contains the most recent lessons and successes from the 25 Solar America Cities and other communities promoting solar energy. Because DOE recognizes that there is no one path to solar market development, this guide introduces a range of policy and program options that can help a community build a local solar infrastructure.

  7. HYBRID FUEL CELL-SOLAR CELL SPACE POWER SUBSYSTEM CAPABILITY.

    Science.gov (United States)

    This report outlines the capabilities and limitations of a hybrid solar cell- fuel cell space power subsystem by comparing the proposed hybrid system...to conventional power subsystem devices. The comparisons are based on projected 1968 capability in the areas of primary and secondary battery, fuel ... cell , solar cell, and chemical dynamic power subsystems. The purpose of the investigation was to determine the relative merits of a hybrid power

  8. Polar and equatorial coronal hole winds at solar minima: From the heliosphere to the inner corona

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, L.; Landi, E., E-mail: lzh@umich.edu [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, Ann Arbor, MI 48105 (United States)

    2014-02-01

    Fast solar wind can be accelerated from at least two different sources: polar coronal holes and equatorial coronal holes. Little is known about the relationship between the wind coming from these two different latitudes and whether these two subcategories of fast wind evolve in the same way during the solar cycle. Nineteen years of Ulysses observations, from 1990 to 2009, combined with ACE observations from 1998 to the present provide us with in situ measurements of solar wind properties that span two entire solar cycles. These missions provide an ideal data set to study the properties and evolution of the fast solar wind originating from equatorial and polar holes. In this work, we focus on these two types of fast solar wind during the minima between solar cycles 22 and 23 and 23 and 24. We use data from SWICS, SWOOPS, and VHM/FGM on board Ulysses and SWICS, SWEPAM, and MAG on board ACE to analyze the proton kinetic, thermal, and dynamic characteristics, heavy ion composition, and magnetic field properties of these two fast winds. The comparison shows that: (1) their kinetic, thermal, compositional, and magnetic properties are significantly different at any time during the two minima and (2) they respond differently to the changes in solar activity from cycle 23 to 24. These results indicate that equatorial and polar fast solar wind are two separate subcategories of fast wind. We discuss the implications of these results and relate them to remote-sensing measurements of the properties of polar and equatorial coronal holes carried out in the inner corona during these two solar minima.

  9. Polar and equatorial coronal hole winds at solar minima: From the heliosphere to the inner corona

    International Nuclear Information System (INIS)

    Zhao, L.; Landi, E.

    2014-01-01

    Fast solar wind can be accelerated from at least two different sources: polar coronal holes and equatorial coronal holes. Little is known about the relationship between the wind coming from these two different latitudes and whether these two subcategories of fast wind evolve in the same way during the solar cycle. Nineteen years of Ulysses observations, from 1990 to 2009, combined with ACE observations from 1998 to the present provide us with in situ measurements of solar wind properties that span two entire solar cycles. These missions provide an ideal data set to study the properties and evolution of the fast solar wind originating from equatorial and polar holes. In this work, we focus on these two types of fast solar wind during the minima between solar cycles 22 and 23 and 23 and 24. We use data from SWICS, SWOOPS, and VHM/FGM on board Ulysses and SWICS, SWEPAM, and MAG on board ACE to analyze the proton kinetic, thermal, and dynamic characteristics, heavy ion composition, and magnetic field properties of these two fast winds. The comparison shows that: (1) their kinetic, thermal, compositional, and magnetic properties are significantly different at any time during the two minima and (2) they respond differently to the changes in solar activity from cycle 23 to 24. These results indicate that equatorial and polar fast solar wind are two separate subcategories of fast wind. We discuss the implications of these results and relate them to remote-sensing measurements of the properties of polar and equatorial coronal holes carried out in the inner corona during these two solar minima.

  10. A Comparative Study of Magnetic Fields in the Solar Photosphere and Chromosphere at Equatorial and Polar Latitudes

    Science.gov (United States)

    Petrie, G. J. D.; Patrikeeva, I.

    2009-07-01

    Besides their own intrinsic interest, correct interpretation of solar surface magnetic field observations is crucial to our ability to describe the global magnetic structure of the solar atmosphere. Photospheric magnetograms are often used as lower boundary conditions in models of the corona, but not data from the nearly force-free chromosphere. National Solar Observatory's (NSO) Synoptic Optical Long-term Investigations of the Sun VSM (Vector Spectromagnetograph) produces full-disk line-of-sight magnetic flux images deriving from both photospheric and chromospheric layers on a daily basis. In this paper, we investigate key properties of the magnetic field in these two layers using more than five years of VSM data. We find from near-equatorial measurements that the east-west inclination angle of most photospheric fields is less than about 12°, while chromospheric fields expand in all directions to a significant degree. Using a simple stereoscopic inversion, we find evidence that photospheric polar fields are also nearly radial but that during 2008 the chromospheric field in the south pole was expanding superradially. We obtain a spatially resolved polar photospheric flux distribution up to 80° latitude whose strength increases poleward approximately as cosine(colatitude) to the power 9-10. This distribution would give a polar field strength of 5-6 G. We briefly discuss implications for future synoptic map construction and modeling.

  11. The research and development of the automatic solar power tracker

    OpenAIRE

    Li Yan Ping; Yuan Zhong Ying

    2016-01-01

    The article describes a kind of automatic tracker using solar power. It depends on two important parts which are servo system and adjusting mechanism system to keep the tracker operating normally. The article focuses on describing the characteristics and functions of two systems and the operating details of the automatic solar power tracker.

  12. The research and development of the automatic solar power tracker

    Directory of Open Access Journals (Sweden)

    Li Yan Ping

    2016-01-01

    Full Text Available The article describes a kind of automatic tracker using solar power. It depends on two important parts which are servo system and adjusting mechanism system to keep the tracker operating normally. The article focuses on describing the characteristics and functions of two systems and the operating details of the automatic solar power tracker.

  13. POLAR NETWORK INDEX AS A MAGNETIC PROXY FOR THE SOLAR CYCLE STUDIES

    International Nuclear Information System (INIS)

    Priyal, Muthu; Banerjee, Dipankar; Ravindra, B.; Singh, Jagdev; Karak, Bidya Binay; Muñoz-Jaramillo, Andrés; Choudhuri, Arnab Rai

    2014-01-01

    The Sun has a polar magnetic field which oscillates with the 11 yr sunspot cycle. This polar magnetic field is an important component of the dynamo process which operates in the solar convection zone and produces the sunspot cycle. We have direct systematic measurements of the Sun's polar magnetic field only from about the mid-1970s. There are, however, indirect proxies which give us information about this field at earlier times. The Ca-K spectroheliograms taken at the Kodaikanal Solar Observatory during 1904-2007 have now been digitized with 4k × 4k CCD and have higher resolution (∼0.86 arcsec) than the other available historical data sets. From these Ca-K spectroheliograms, we have developed a completely new proxy (polar network index, hereafter PNI) for the Sun's polar magnetic field. We calculate PNI from the digitized images using an automated algorithm and calibrate our measured PNI against the polar field as measured by the Wilcox Solar Observatory for the period 1976-1990. This calibration allows us to estimate the polar fields for the earlier period up to 1904. The dynamo calculations performed with this proxy as input data reproduce reasonably well the Sun's magnetic behavior for the past century

  14. Marketing of green electrons. Solar-power stock exchanges

    International Nuclear Information System (INIS)

    Nussbaumer-Waelti, E.

    1999-01-01

    An independent power producer evaluates the current solar-power stock exchanges in Switzerland. Most stock exchanges have been created by electric utilities which want to deliver 'green' power to those of their clients asking for. A first group of solar-power stock exchanges offer to take over the produced solar power at a marginal price. Among them, some organise a competition between the potential solar-power producers, in order to press down the investment cost for the new photovoltaic plants to build. Other stock exchanges propose a periodical adaptation of the prices, especially an adaptation to the capital interest rate. For sure, the total length of the time period for which the contract is established is one of the decisive factors. Because no bank is ready to grant a credit for such an investment without having seen a long-running take-over contract for the produced power [de

  15. HEMISPHERIC ASYMMETRIES IN THE POLAR SOLAR WIND OBSERVED BY ULYSSES NEAR THE MINIMA OF SOLAR CYCLES 22 AND 23

    Energy Technology Data Exchange (ETDEWEB)

    Ebert, R. W.; Dayeh, M. A.; Desai, M. I.; McComas, D. J. [Southwest Research Institute, P.O. Drawer 28510, San Antonio, TX 78228 (United States); Pogorelov, N. V. [Physics Department, University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

    2013-05-10

    We examined solar wind plasma and interplanetary magnetic field (IMF) observations from Ulysses' first and third orbits to study hemispheric differences in the properties of the solar wind and IMF originating from the Sun's large polar coronal holes (PCHs) during the declining and minimum phase of solar cycles 22 and 23. We identified hemispheric asymmetries in several parameters, most notably {approx}15%-30% south-to-north differences in averages for the solar wind density, mass flux, dynamic pressure, and energy flux and the radial and total IMF magnitudes. These differences were driven by relatively larger, more variable solar wind density and radial IMF between {approx}36 Degree-Sign S-60 Degree-Sign S during the declining phase of solar cycles 22 and 23. These observations indicate either a hemispheric asymmetry in the PCH output during the declining and minimum phase of solar cycles 22 and 23 with the southern hemisphere being more active than its northern counterpart, or a solar cycle effect where the PCH output in both hemispheres is enhanced during periods of higher solar activity. We also report a strong linear correlation between these solar wind and IMF parameters, including the periods of enhanced PCH output, that highlight the connection between the solar wind mass and energy output and the Sun's magnetic field. That these enhancements were not matched by similar sized variations in solar wind speed points to the mass and energy responsible for these increases being added to the solar wind while its flow was subsonic.

  16. Direct Drive Solar-Powered Arcjet Thruster

    Science.gov (United States)

    Polzin, Kurt; Martin, Adam

    2015-01-01

    Electric thrusters typically require a power processing unit (PPU) to convert the spacecraft-provided power to the voltage and current that a thruster needs for operation. NASA Marshall Space Flight Center has initiated fundamental studies on whether an arcjet thruster can be operated directly with the power produced by solar arrays without any additional conversion. Elimination of the PPU significantly reduces system-level complexity of the propulsion system, and lowers developmental cost and risk. The proposed work will aim to refine the proof-of-concept presently being assembled and begin to identify and address technical questions related to power conditioning and noise suppression in the system, and heating of the thruster in long-duration operation. The apparatus proposed for investigation has a target power level of 400 to 1,000 W. The proposed direct-drive arcjet is potentially a highly scalable concept, applicable to spacecraft with up to hundreds of kilowatts and beyond. The design of the arcjet built for this effort was based on previous low power (1 kW class) arcjets.1-3 It has a precision machined 99.95% pure tungsten anode that also serves as the nozzle with a 0.040-in- (1-mm-) diameter, 0.040-in-long constrictor region. An additional anode with a 0.020-in- (0.5-mm-) diameter, 0.020-inlong constrictor region was purchased, but has not yet been used. The cathode is a 0.125-in-diameter tungsten welding electrode doped with lanthum-oxygen; its tip was precision ground to a 308deg angle and terminates in a blunt end. The two electrodes are separated by a boron-nitride insulator that also serves as the propellant manifold; it ends in six small holes which introduce the propellant gas in the diverging section of the nozzle, directly adjacent to the cathode. The electrodes and insulator are housed in a stainless-steel outer body, with a Macor insulator at the mid-plane to provide thermal isolation between the front and back halves of the device. The gas

  17. Impact of climate change on future concentrated solar power (CSP) production

    Science.gov (United States)

    Wild, Martin; Folini, Doris; Henschel, Florian

    2017-02-01

    Traditionally, for the planning and assessment of solar power plants, the amount of solar radiation incident on the Earth's surface is assumed to be invariable 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 several decades indeed confirm long-term changes in this quantity. In a previous study (Wild et al. 2015, Solar Energy)1 we examined how the latest generation of climate models (CMIP5) projects potential changes in surface solar radiation over the coming decades, and how this may affect, in combination with the expected greenhouse warming, future power output from photovoltaic (PV) systems. In the present complementary study, we use the CMIP5 model projections to estimate possible future changes in power output from Concentrated Solar Power (CSP) systems due to changing climate and air pollution levels up to the mid-21th century. The results indicate a potential for future increases in CSP production in many parts of the globe, with few exceptions such as the North of India and the irrelevant polar areas. Compared to the changes in PV production, the estimated future production changes by CSP are larger by a factor of 4.

  18. Schools Going Solar: A Guide to Schools Enjoying the Power of Solar Energy. Volume 2.

    Science.gov (United States)

    Hitchcock, Susan Tyler

    This companion document updates an April 1998 volume on designing schools to use solar energy as a power source. Volume 2 presents numerous case studies of solar installations in new and existing schools across the United States and Europe, updates and presents new examples of solar education programs, and offers an updated resource listing of…

  19. Solar Power in the Middle East

    Science.gov (United States)

    Hayes, Denis

    1975-01-01

    Describes the present state of solar technology, points out the need for research and development in this area, and indicates the important role solar technology could play in Third World development. (GS)

  20. Thermal design guidelines of solar power towers

    International Nuclear Information System (INIS)

    Rodríguez-Sánchez, M.R.; Soria-Verdugo, Antonio; Almendros-Ibáñez, José Antonio; Acosta-Iborra, Antonio; Santana, Domingo

    2014-01-01

    One of the main problems of solar power tower plants with molten salt as heat transfer fluid is the reliability of central receivers. The receiver must withstand high working temperatures, molten salt corrosion and important solar flux transients that lead to thermal stresses and fatigue. Despite these difficulties, it is necessary an estimation of the receiver thermal efficiency in order to have an accurate estimation of the investment cost of the solar plant and to assure the lifetime estimation of the receiver. A thermal, mechanical and hydrodynamic analysis of these receivers has been developing in this work, assuming constant heat flux in each axial discretized section of the tube wall but considering circumferential temperature variations in the perimeter of the tubes caused by the difference between the heat flux received by the front part of the tubes and by the rear part. The thermal analysis shows that the radiation losses are higher than in literature, and consequently the thermal efficiency is lower too. This is due to the fact that the effective tube wall temperature for radiation is higher than the mean tube wall temperature, especially if the rear temperature of the tubes is considered. Besides, it has been found that the highest temperatures and thermal stresses are sited on the eastern and western panels of the receivers. Film temperature is the most limiting parameter for the receiver design due to it is responsible for salt decomposition and tube corrosion. Therefore, once the tube material is chosen, the film temperature cannot exceed a critical value over which the corrosion ratio raises rapidly. Small tube diameters and low number of panels results in low film temperatures, although this kind of design increases the pressure drop. Therefore, a compromise between film temperature and pressure drop can lead to a receiver design that ensures its lifetime, and at the same time, optimizes the investment and operational cost of the receiver

  1. The Evaluation of Solar Contribution in Solar Aided Coal-Fired Power Plant

    Directory of Open Access Journals (Sweden)

    Rongrong Zhai

    2013-01-01

    Full Text Available Solar aided coal-fired power plants utilize various types of solar thermal energy for coupling coal-fired power plants by using the characteristics of various thermal needs of the plants. In this way, the costly thermal storage system and power generating system will be unnecessary while the intermittent and unsteady way of power generation will be avoided. Moreover, the large-scale utilization of solar thermal power and the energy-saving aim of power plants will be realized. The contribution evaluating system of solar thermal power needs to be explored. This paper deals with the evaluation method of solar contribution based on the second law of thermodynamics and the principle of thermoeconomics with a case of 600 MW solar aided coal-fired power plant. In this study, the feasibility of the method has been carried out. The contribution of this paper is not only to determine the proportion of solar energy in overall electric power, but also to assign the individual cost components involving solar energy. Therefore, this study will supply the theoretical reference for the future research of evaluation methods and new energy resource subsidy.

  2. Rankine-Brayton engine powered solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L [Livermore, CA

    2009-12-29

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

  3. Rankline-Brayton engine powered solar thermal aircraft

    Science.gov (United States)

    Bennett, Charles L [Livermore, CA

    2012-03-13

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

  4. Power management circuits for self-powered systems based on micro-scale solar energy harvesting

    Science.gov (United States)

    Yoon, Eun-Jung; Yu, Chong-Gun

    2016-03-01

    In this paper, two types of power management circuits for self-powered systems based on micro-scale solar energy harvesting are proposed. First, if a solar cell outputs a very low voltage, less than 0.5 V, as in miniature solar cells or monolithic integrated solar cells, such that it cannot directly power the load, a voltage booster is employed to step up the solar cell's output voltage, and then a power management unit (PMU) delivers the boosted voltage to the load. Second, if the output voltage of a solar cell is enough to drive the load, the PMU directly supplies the load with solar energy. The proposed power management systems are designed and fabricated in a 0.18-μm complementary metal-oxide-semiconductor process, and their performances are compared and analysed through measurements.

  5. Study of the Effect of Active Regions on the Scattering Polarization in the Solar Corona

    Science.gov (United States)

    Derouich, M.; Badruddin

    2018-03-01

    The solar photospheric/chromospheric light exciting atoms/ions is not homogeneous because of the presence of active regions (ARs). The effect of ARs on the scattering polarization at the coronal level is an important ingredient for a realistic determination of the magnetic field. This effect is usually disregarded or mixed with other effects in the sense that the degree of its importance is not well known. The aim of this paper is to study the effect of atmospheric inhomogeneities on the coronal scattering polarization. We determined quantitatively the importance of the atmospheric inhomogeneities by using given geometries of solar ARs (plages and sunspots).

  6. The Future of Solar Power in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Gerard Reid

    2015-07-01

    Full Text Available We used detailed industry data to analyse the impacts of expected further cost reductions on the competitiveness of solar power in Britain, and assess whether the solar market can survive without support in the near future. We investigated three solar power markets: large-scale, ground-mounted “solar farms” (defined in our analysis as larger than a 5000 kilowatt system; commercial roof-top (250 kW; and residential rooftop (3 kW. We found that all three would be economic without support in the next decade. Such an outcome assumes progressively falling support under a stable policy regime. We found that unsubsidised residential solar power may be cheaper with battery storage within the next five to 10 years. Unsupported domestic solar battery packs achieve payback periods of less than 10 years by 2025. That could create an inflexion point driving adoption of domestic solar systems. The variability of solar power will involve some grid integration costs at higher penetration levels, such as more frequent power market scheduling; more interconnector capacity; storage; and backup power. These costs and responses could be weighed against non-market benefits including the potential for grid balancing; lower carbon and particulate emissions; and energy security.

  7. Power Converters Maximize Outputs Of Solar Cell Strings

    Science.gov (United States)

    Frederick, Martin E.; Jermakian, Joel B.

    1993-01-01

    Microprocessor-controlled dc-to-dc power converters devised to maximize power transferred from solar photovoltaic strings to storage batteries and other electrical loads. Converters help in utilizing large solar photovoltaic arrays most effectively with respect to cost, size, and weight. Main points of invention are: single controller used to control and optimize any number of "dumb" tracker units and strings independently; power maximized out of converters; and controller in system is microprocessor.

  8. Evaluation methods of solar contribution in solar aided coal-fired power generation system

    International Nuclear Information System (INIS)

    Zhu, Yong; Zhai, Rongrong; Zhao, Miaomiao; Yang, Yongping; Yan, Qin

    2015-01-01

    Highlights: • Five methods for evaluating solar contribution are analyzed. • Method based on the second law of thermodynamics and thermal economics is more suitable for SACPGS. • Providing reliable reference for the formulation of feed-in tariff policies in China. - Abstract: Solar aided coal-fired power plants utilize solar thermal energy to couple with coal-fired power plants of various types by adopting characteristics of different thermal needs of plants. In this way, the costly thermal storage system and power generating system will become unnecessary, meanwhile the intermittent and unsteady nature of power generation can be avoided. In addition, large-scale utilization of solar thermal power and energy saving can be achieved. With the ever-deepening analyses of solar aided coal-fired power plants, the contribution evaluating system of solar thermal power is worth further exploration. In this paper, five common evaluation methods of solar contribution are analyzed, and solar aided coal-fired power plants of 1000 MW, 600 MW and 330 MW are studied with these five methods in a comparative manner. Therefore, this study can serve as a theoretical reference for future research of evaluation methods and subsidies for new energy

  9. Is solar power too expensive? In the long term, no

    International Nuclear Information System (INIS)

    Hawkins, A. C.

    2007-01-01

    This short article reports on a workshop held by the International Energy Agency (IEA) in Zurich, Switzerland, which addressed the question if solar power is too expensive. The article summarises the presentations of energy and financial experts from around the world who attended the workshop. Developments in solar technology, traditional energy supply and the various applications of solar energy are discussed. Marketing aspects and price developments are examined and the risks and chances offered by the solar business are discussed. The lack of purchasing power in developing countries is also addressed.

  10. Proton irradiation effects of amorphous silicon solar cell for solar power satellite

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Yousuke; Oshima, Takeshi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment; Sasaki, Susumu; Kuroda, Hideo; Ushirokawa, Akio

    1997-03-01

    Flexible amorphous silicon(fa-Si) solar cell module, a thin film type, is regarded as a realistic power generator for solar power satellite. The radiation resistance of fa-Si cells was investigated by the irradiations of 3,4 and 10 MeV protons. The hydrogen gas treatment of the irradiated fa-Si cells was also studied. The fa-Si cell shows high radiation resistance for proton irradiations, compared with a crystalline silicon solar cell. (author)

  11. Using Power Purchase Agreements for Solar Deployment at Universities

    Energy Technology Data Exchange (ETDEWEB)

    Heeter, Jenny; O' Shaughnessy, Eric

    2016-02-24

    More than 60 universities have used solar power purchase agreements (PPAs) to deploy more than 100 megawatts of solar PV on campuses around the country. This webinar is intended for university financial planners and other stakeholders who are assessing the financial aspects of deploying solar. The speakers will provide an overview of how universities are using PPAs and key PPA components. In addition, they will discuss the process of using PPAs, why PPAs make sense for campus solar deployment, and the benefits and challenges for universities. Tools and other resources will be shared to help universities interested in using PPAs for campus solar deployment.

  12. Coronal temperatures, heating, and energy flow in a polar region of the sun at solar maximum

    Science.gov (United States)

    Withbroe, G. L.; Kohl, J. L.; Weiser, H.; Munro, R. H.

    1985-01-01

    The profiles of resonantly scattered Lyman-alpha coronal radiation have been used to determine the hydrogen kinetic temperature from 1.5 to 4 solar radius from the center of the polar region of the corona observed in 1980 at solar maximum. Hydrogen temperatures derived from the line profiles were found to decrease with height from 1.2 million K at r = 1.5 solar radii to 600,000 K at r = 4 solar radius. Comparison of the measured kinetic temperatures with predictions from a semiempirical two-fluid model showed evidence of a small amount of heating or a nonthermal contribution to the motions of coronal protons between 1.5 and 4 solar radius. The widths of the profiles confirmed an upper limit of 110 + or - 15 km/s on the rms magnitude of the line-of-sight component of velocities between 1.5 and 4 solar radius. Density measurements obtained in situ in the solar wind in the ecliptic were used to locate the sources of low speed and high-speed winds in the polar region. An eclipse photograph of the corona at solar maximum is provided.

  13. Effect of III-nitride polarization on V{sub OC} in p-i-n and MQW solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Namkoong, Gon; Boland, Patrick; Foe, Kurniawan; Latimer, Kevin [Department of Electrical and Computer Engineering, Old Dominion University, Applied Research Center, 12050 Jefferson Avenue, Newport News, VA 23606 (United States); Bae, Si-Young; Shim, Jae-Phil; Lee, Dong-Seon [School of Information and Communications, Gwangju Institute of Science and Technology, 261 Cheomdan-gwagiro (Oryong-dong), Buk-gu, Gwangju 500-712 (Korea, Republic of); Jeon, Seong-Ran [Korea Photonics Technology Institute, 971-35, Wolchul-dong, Buk-gu, Gwangju, 500-779 (Korea, Republic of); Doolittle, W. Alan [School of Electrical and Computer Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States)

    2011-02-15

    We performed detailed studies of the effect of polarization on III-nitride solar cells. Spontaneous and piezoelectric polarizations were assessed to determine their impacts upon the open circuit voltages (V{sub OC}) in p-i(InGaN)-n and multi-quantum well (MQW) solar cells. We found that the spontaneous polarization in Ga-polar p-i-n solar cells strongly modifies energy band structures and corresponding electric fields in a way that degrades V{sub OC} compared to non-polar p-i-n structures. In contrast, we found that piezoelectric polarization in Ga-polar MQW structures does not have a large influence on V{sub OC} compared to non-polar MQW structures. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. MCU-Based Solar Powered Chicken Feeder

    Directory of Open Access Journals (Sweden)

    Elenor M. Reyes

    2015-12-01

    Full Text Available Poultry is a great potential industry particularly in Batangas Province. The method of feeding chicken needs to be considered as chicken must be fed regularly to be more productive. The conventional method of feeding chicken is the need to continuously provide the food, be alert and conscious on the food remaining in cages and to feed the chickens in a correct period of time to avoid the decline of the production. Growers also find it difficult to manage their businesses effectively because they need to be around the cages every now and then to monitor the poultry. Timing and exactness are the key to provide a uniform time in feeding the chickens. This will benefit the owner of the business in terms of time and effort. Another advantage of this project is in terms of savings to the owner of the poultry business. This technology was designed to automatically feed chickens at a given period of time and to give alarm when the feeds are running out of supply. The power to be supplied to this prototype will be drawn from the sun by means of solar panels and will be stored in typical car battery. The feeds will be stored in a container and evenly distributed by using a conveyor to the feeding basin of the poultry. It will be more efficient than manual conventional way of feeding because less effort will be needed in feeding the chickens and less feeds will be wasted. In addition to that, the stored power can also be used for lighting purposes for the growers to save energy and energy bills.

  15. Light funnel concentrator panel for solar power

    Science.gov (United States)

    1987-01-01

    The solar concentrator design concept provides a theoretical concentration efficiency of 96 percent with power-to-weight ratios as high as 50 W/kg. Further, it eliminates the need for fragile reflective coatings and is very tolerant to pointing inaccuracies. The concept differs from conventional reflective mirrors and lens design in that is uses the principle of total internal reflection in order to funnel incident sunlight into a concentrator photovoltaic cell. The feasibility of the light funnel concentrator concept was determined through a balanced approach of analysis, development, and fabrication of prototypes, and testing of components. A three-dimensional optical model of the light funnel concentrator and photovoltaic cell was developed in order to assess the ultimate performance of such systems. In addition, a thermal and structural analysis of a typical unit was made. Techniques of fabricating the light funnel cones, optically coupling them to GaAs concentrator cells, bonding the funnels to GaAs cells, making electrical interconnects, and bonding substrates was explored and a prototype light funnel concentrator unit was fabricated and tested. Testing of the system included measurements of optical concentrating efficiency, optical concentrator to cell coupling efficiency, and electrical efficiency.

  16. Methods and systems for concentrated solar power

    Science.gov (United States)

    Ma, Zhiwen

    2016-05-24

    Embodiments described herein relate to a method of producing energy from concentrated solar flux. The method includes dropping granular solid particles through a solar flux receiver configured to transfer energy from concentrated solar flux incident on the solar flux receiver to the granular solid particles as heat. The method also includes fluidizing the granular solid particles from the solar flux receiver to produce a gas-solid fluid. The gas-solid fluid is passed through a heat exchanger to transfer heat from the solid particles in the gas-solid fluid to a working fluid. The granular solid particles are extracted from the gas-solid fluid such that the granular solid particles can be dropped through the solar flux receiver again.

  17. Sustainable Buildings. Using Active Solar Power

    Energy Technology Data Exchange (ETDEWEB)

    Sharp, M. Keith [Univ. of Louisville, KY (United States); Barnett, Russell [Univ. of Louisville, KY (United States)

    2015-04-20

    The objective of this project is to promote awareness and knowledge of active solar energy technologies by installing and monitoring the following demonstration systems in Kentucky: 1) Pool heating system, Churchill Park School, 2) Water heating and daylighting systems, Middletown and Aiken Road Elementary Schools, 3) Photovoltaic street light comparison, Louisville Metro, 4) up to 25 domestic water heating systems across Kentucky. These tasks will be supported by outreach activities, including a solar energy installer training workshop and a Kentucky Solar Energy Conference.

  18. Thermal energy storage for CSP (Concentrating Solar Power

    Directory of Open Access Journals (Sweden)

    Py Xavier

    2017-01-01

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

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

    Science.gov (United States)

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

    2017-07-01

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

  20. Solar particle effects on minor components of the Polar atmosphere

    Directory of Open Access Journals (Sweden)

    A. Damiani

    2008-02-01

    Full Text Available Solar activity can influence the Earth's environment, and in particular the ozone layer, by direct modulation of the e.m. radiation or through variability of the incoming cosmic ray flux (solar and galactic particles. In particular, solar energetic particles (SEPs provide additional external energy to the terrestrial environment; they are able to interact with the minor constituents of the atmospheric layer and produce ionizations, dissociations, dissociative ionizations and excitations. This paper highlights the SEP effects on the chemistry of the upper atmosphere by analysing some SEP events recorded during 2005 in the descending phase of the current solar cycle. It is shown that these events can lead to short- (hours and medium- (days term ozone variations through catalytic cycles (e.g. HOx and NOx increases. We focus attention on the relationship between ozone and OH data (retrieved from MLS EOS AURA for four SEP events: 17 and 20 January, 15 May and 8 September. We confirm that SEP effects are different on the night and day hemispheres at high latitudes.

  1. Mechanism of Cyclically Polarity Reversing Solar Magnetic Cycle as ...

    Indian Academy of Sciences (India)

    tribpo

    solar dynamo mechanism that generates electric current and magnetic field by plasma flows inside the .... on the flow which makes the flow pattern twist and propagate to drive the dynamo must be strong enough to .... drive electric current in cosmos, Elsassar, a friend of Einstein, proposed that non- axisymmetric flows could ...

  2. Heat Rate Enhancement of IGCC Power Plant Coupled with Solar thermal power plant

    OpenAIRE

    Kotdawala, Rasesh R; V., Jyothi; Kanaujia, Gaurav; Adapa, Bharath

    2016-01-01

    Integrated gasification  combined cycle power plant (IGCC) has shown the potential of having higher operating thermal efficiency, than supercritical thermal power plants as it combines the advantages of coal gasification and combined cycle power plant. Solar thermal plant has shown great promise to augment the thermal efficiency of the fossil based power plants and reducing CO2 emissions. In this research paper, impact of integrating solar thermal power plant utilizing linear Fresnel collecto...

  3. An Empirical Orthogonal Function Reanalysis of the Northern Polar External and Induced Magnetic Field During Solar Cycle 23

    Science.gov (United States)

    Shore, R. M.; Freeman, M. P.; Gjerloev, J. W.

    2018-01-01

    We apply the method of data-interpolating empirical orthogonal functions (EOFs) to ground-based magnetic vector data from the SuperMAG archive to produce a series of month length reanalyses of the surface external and induced magnetic field (SEIMF) in 110,000 km2 equal-area bins over the entire northern polar region at 5 min cadence over solar cycle 23, from 1997.0 to 2009.0. Each EOF reanalysis also decomposes the measured SEIMF variation into a hierarchy of spatiotemporal patterns which are ordered by their contribution to the monthly magnetic field variance. We find that the leading EOF patterns can each be (subjectively) interpreted as well-known SEIMF systems or their equivalent current systems. The relationship of the equivalent currents to the true current flow is not investigated. We track the leading SEIMF or equivalent current systems of similar type by intermonthly spatial correlation and apply graph theory to (objectively) group their appearance and relative importance throughout a solar cycle, revealing seasonal and solar cycle variation. In this way, we identify the spatiotemporal patterns that maximally contribute to SEIMF variability over a solar cycle. We propose this combination of EOF and graph theory as a powerful method for objectively defining and investigating the structure and variability of the SEIMF or their equivalent ionospheric currents for use in both geomagnetism and space weather applications. It is demonstrated here on solar cycle 23 but is extendable to any epoch with sufficient data coverage.

  4. Detecting photovoltaic solar panels using hyperspectral imagery and estimating solar power production

    Science.gov (United States)

    Czirjak, Daniel

    2017-04-01

    Remote sensing platforms have consistently demonstrated the ability to detect, and in some cases identify, specific targets of interest, and photovoltaic solar panels are shown to have a unique spectral signature that is consistent across multiple manufacturers and construction methods. Solar panels are proven to be detectable in hyperspectral imagery using common statistical target detection methods such as the adaptive cosine estimator, and false alarms can be mitigated through the use of a spectral verification process that eliminates pixels that do not have the key spectral features of photovoltaic solar panel reflectance spectrum. The normalized solar panel index is described and is a key component in the false-alarm mitigation process. After spectral verification, these solar panel arrays are confirmed on openly available literal imagery and can be measured using numerous open-source algorithms and tools. The measurements allow for the assessment of overall solar power generation capacity using an equation that accounts for solar insolation, the area of solar panels, and the efficiency of the solar panels conversion of solar energy to power. Using a known location with readily available information, the methods outlined in this paper estimate the power generation capabilities within 6% of the rated power.

  5. A parametric simulation of solar chimney power plant

    Science.gov (United States)

    Beng Hooi, Lim; Kannan Thangavelu, Saravana

    2018-01-01

    The strong solar radiation, continuous supplies of sunlight and environmental friendly factors have made the solar chimney power plant becoming highly feasible to build in Malaysia. Solar chimney power plant produces upward buoyancy force through the greenhouse effect. Numerical simulation was performed on the model of a solar chimney power plant using the ANSYS Fluent software by applying standard k-epsilon turbulence model and discrete ordinates (DO) radiation model to solve the relevant equations. A parametric study was carried out to evaluate the performance of solar chimney power plant, which focused on the temperature rise in the collector, air velocity at the chimney base, and pressure drop inside the chimney were based on the results of temperature, velocity, and static pressure distributions. The results demonstrate reliability by comparing a model with the experimental data of Manzanares Spanish prototype. Based on the numerical results, power capacity and efficiency were analysed theoretically. Results indicate that a stronger solar radiation and larger prototype will improve the performance of solar chimney power plant.

  6. Grid-Parity Solar Power for Department of Defense Installations

    Science.gov (United States)

    2014-02-01

    Economics (LCOE). $0.110/kWh real dollar LCOE. $3.20/W solar power plant cost. Energy generated & performance degradation. Cost of solar ...This includes uptime of all components of the plant including the solar panels, inverters, and all BoS Components. Photovoltaic Peak Capacity...periodic basis. SAM incorporates the best available models to provide optimal analysis of overall economics , including the levelized cost of

  7. Progress commercializing solar-electric power systems

    International Nuclear Information System (INIS)

    Dracker, R.; De Laquil, P. III

    1996-01-01

    The commercial status of the principal solar electric technologies -- photovoltaic and solar thermal -- is reviewed. Current and near-term market niches are identified, and projected longer-term markets are explored along with the key strategies for achieving them, including technological breakthroughs, manufacturing developments, economies of scale and mass production, and market creation. Market barriers and public policy impacts on commercialization are discussed

  8. Experimental Investigation of Solar Powered Reverse Osmosis ...

    African Journals Online (AJOL)

    This paper deals with application of reverse osmosis, driven by desalination system using solar energy, to supply safe drinking water for the rural areas of northern Ethiopia. ... The entire process of irradiation potential measurements, the amount of energy generated using solar panel, and the amount of TDS is discussed.

  9. THERMOCHEMICAL HEAT STORAGE FOR CONCENTRATED SOLAR POWER

    Energy Technology Data Exchange (ETDEWEB)

    PROJECT STAFF

    2011-10-31

    Thermal energy storage (TES) is an integral part of a concentrated solar power (CSP) system. It enables plant operators to generate electricity beyond on sun hours and supply power to the grid to meet peak demand. Current CSP sensible heat storage systems employ molten salts as both the heat transfer fluid and the heat storage media. These systems have an upper operating temperature limit of around 400 C. Future TES systems are expected to operate at temperatures between 600 C to 1000 C for higher thermal efficiencies which should result in lower electricity cost. To meet future operating temperature and electricity cost requirements, a TES concept utilizing thermochemical cycles (TCs) based on multivalent solid oxides was proposed. The system employs a pair of reduction and oxidation (REDOX) reactions to store and release heat. In the storage step, hot air from the solar receiver is used to reduce the oxidation state of an oxide cation, e.g. Fe3+ to Fe2+. Heat energy is thus stored as chemical bonds and the oxide is charged. To discharge the stored energy, the reduced oxide is re-oxidized in air and heat is released. Air is used as both the heat transfer fluid and reactant and no storage of fluid is needed. This project investigated the engineering and economic feasibility of this proposed TES concept. The DOE storage cost and LCOE targets are $15/kWh and $0.09/kWh respectively. Sixteen pure oxide cycles were identified through thermodynamic calculations and literature information. Data showed the kinetics of re-oxidation of the various oxides to be a key barrier to implementing the proposed concept. A down selection was carried out based on operating temperature, materials costs and preliminary laboratory measurements. Cobalt oxide, manganese oxide and barium oxide were selected for developmental studies to improve their REDOX reaction kinetics. A novel approach utilizing mixed oxides to improve the REDOX kinetics of the selected oxides was proposed. It partially

  10. Discovery of Scattering Polarization in the Hydrogen Ly α Line of the Solar Disk Radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kano, R.; Narukage, N.; Ishikawa, R.; Bando, T.; Katsukawa, Y.; Kubo, M.; Giono, G.; Hara, H.; Suematsu, Y. [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Bueno, J. Trujillo [Instituto de Astrofísica de Canarias, La Laguna, Tenerife, E-38205 (Spain); Winebarger, A.; Kobayashi, K. [Marshall Space Flight Center, National Aeronautics and Space Administration (NASA), Huntsville, AL 35812 (United States); Auchère, F. [Institut d’Astrophysique Spatiale, Université Paris Sud, Batiment 121, F-91405 Orsay (France); Ishikawa, S.; Shimizu, T.; Sakao, T.; Tsuneta, S. [Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, 3-1-1 Yoshinodai, Chuo, Sagamihara, Kanagawa 252-5210 (Japan); Ichimoto, K. [Hida Observatory, Kyoto University, Takayama, Gifu 506-1314 (Japan); Goto, M. [National Institute for Fusion Science, Toki, Gifu 509-5292 (Japan); Belluzzi, L., E-mail: ryouhei.kano@nao.ac.jp [Istituto Ricerche Solari Locarno, CH-6605 Locarno Monti (Switzerland); and others

    2017-04-10

    There is a thin transition region (TR) in the solar atmosphere where the temperature rises from 10,000 K in the chromosphere to millions of degrees in the corona. Little is known about the mechanisms that dominate this enigmatic region other than the magnetic field plays a key role. The magnetism of the TR can only be detected by polarimetric measurements of a few ultraviolet (UV) spectral lines, the Ly α line of neutral hydrogen at 121.6 nm (the strongest line of the solar UV spectrum) being of particular interest given its sensitivity to the Hanle effect (the magnetic-field-induced modification of the scattering line polarization). We report the discovery of linear polarization produced by scattering processes in the Ly α line, obtained with the Chromospheric Lyman-Alpha Spectro-Polarimeter (CLASP) rocket experiment. The Stokes profiles observed by CLASP in quiet regions of the solar disk show that the Q / I and U / I linear polarization signals are of the order of 0.1% in the line core and up to a few percent in the nearby wings, and that both have conspicuous spatial variations with scales of ∼10 arcsec. These observations help constrain theoretical models of the chromosphere–corona TR and extrapolations of the magnetic field from photospheric magnetograms. In fact, the observed spatial variation from disk to limb of polarization at the line core and wings already challenge the predictions from three-dimensional magnetohydrodynamical models of the upper solar chromosphere.

  11. Solar Power and Solar Fuels Synthesis Report. Technology, market and research activities 2006-2011

    Energy Technology Data Exchange (ETDEWEB)

    Ridell, Bengt; Nilsson, Ronny; Rehnlund, Bjoern [Grontmij, Stockholm (Sweden); Kasemo, Bengt [Chalmers Univ. of Technology, Goeteborg (Sweden)

    2012-11-01

    The objectives of the synthesis is to survey the situation and give an accumulated and concentrated knowledge about status, needs and opportunities for Swedish research and Swedish industry within the area of solar power and solar fuels, to be used for prioritisation of further efforts. The synthesis shall identify strengths and weaknesses in areas fundamental for development of solar power and solar fuels, focused on the development in Sweden, but in an international context. The synthesis shall also cover proposals for future Swedish research efforts and organisation of future Swedish research programs.

  12. New design algorithm and reliability testing of solar powered near ...

    African Journals Online (AJOL)

    New design algorithm and reliability testing of solar powered near-space flight vehicle for defense and security. ... To overcome this problem, we propose a pseudo-satellite system where telecommunication devices are carried on a perpetually flying solar aircraft cruising at stratospheric altitude. Our aircraft will combine ...

  13. Exploring Solar Power at Zion-Benton High

    Science.gov (United States)

    Kasper, Rick

    1978-01-01

    Developed to provide students with actual hands-on experience in constructing energy-efficient homes and to increase the community's and students' knowledge of solar power as an alternate source of energy, a building trades program at a high school in Zion, Illinois has its students building single-family solar energy homes. (BM)

  14. Solar Power Plants: Dark Horse in the Energy Stable

    Science.gov (United States)

    Caputo, Richard S.

    1977-01-01

    Twelfth in a series of reports on solar energy, this article provides information relating to the following questions: (1) economic cost of solar-thermal-electric central power plants; (2) cost comparison with nuclear or coal plants; (3) locations of this energy source; and (4) its use and social costs. (CS)

  15. Stillwater Hybrid Geo-Solar Power Plant Optimization Analyses

    Energy Technology Data Exchange (ETDEWEB)

    Wendt, Daniel S.; Mines, Gregory L.; Turchi, Craig S.; Zhu, Guangdong; Cohan, Sander; Angelini, Lorenzo; Bizzarri, Fabrizio; Consoli, Daniele; De Marzo, Alessio

    2015-09-02

    The Stillwater Power Plant is the first hybrid plant in the world able to bring together a medium-enthalpy geothermal unit with solar thermal and solar photovoltaic systems. Solar field and power plant models have been developed to predict the performance of the Stillwater geothermal / solar-thermal hybrid power plant. The models have been validated using operational data from the Stillwater plant. A preliminary effort to optimize performance of the Stillwater hybrid plant using optical characterization of the solar field has been completed. The Stillwater solar field optical characterization involved measurement of mirror reflectance, mirror slope error, and receiver position error. The measurements indicate that the solar field may generate 9% less energy than the design value if an appropriate tracking offset is not employed. A perfect tracking offset algorithm may be able to boost the solar field performance by about 15%. The validated Stillwater hybrid plant models were used to evaluate hybrid plant operating strategies including turbine IGV position optimization, ACC fan speed and turbine IGV position optimization, turbine inlet entropy control using optimization of multiple process variables, and mixed working fluid substitution. The hybrid plant models predict that each of these operating strategies could increase net power generation relative to the baseline Stillwater hybrid plant operations.

  16. Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields

    International Nuclear Information System (INIS)

    Chitta, L. P.; Peter, H.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; Noort, M. van; Rodríguez, J. Blanco; Iniesta, J. C. Del Toro; Suárez, D. Orozco; Schmidt, W.; Pillet, V. Martínez; Knölker, M.

    2017-01-01

    How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the solar corona. To address the above question, we use high-resolution line-of-sight magnetic field data from the Imaging Magnetograph eXperiment instrument on the Sunrise balloon-borne observatory and coronal observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory of an emerging active region. We find that the coronal loops are often rooted at the locations with minor small-scale but persistent opposite-polarity magnetic elements very close to the larger dominant polarity. These opposite-polarity small-scale elements continually interact with the dominant polarity underlying the coronal loop through flux cancellation. At these locations we detect small inverse Y-shaped jets in chromospheric Ca ii H images obtained from the Sunrise Filter Imager during the flux cancellation. Our results indicate that magnetic flux cancellation and reconnection at the base of coronal loops due to mixed polarity fields might be a crucial feature for the supply of mass and energy into the corona.

  17. Solar Coronal Loops Associated with Small-scale Mixed Polarity Surface Magnetic Fields

    Energy Technology Data Exchange (ETDEWEB)

    Chitta, L. P.; Peter, H.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; Noort, M. van [Max-Planck-Institut für Sonnensystemforschung, Justus-von-Liebig-Weg 3, D-37077 Göttingen (Germany); Rodríguez, J. Blanco [Grupo de Astronomía y Ciencias del Espacio, Universidad de Valencia, E-46980 Paterna, Valencia (Spain); Iniesta, J. C. Del Toro; Suárez, D. Orozco [Instituto de Astrofísica de Andalucía (CSIC), Apartado de Correos 3004, E-18080 Granada (Spain); Schmidt, W. [Kiepenheuer-Institut für Sonnenphysik, Schöneckstr. 6, D-79104 Freiburg (Germany); Pillet, V. Martínez [National Solar Observatory, 3665 Discovery Drive, Boulder, CO 80303 (United States); Knölker, M., E-mail: chitta@mps.mpg.de [High Altitude Observatory, National Center for Atmospheric Research, P.O. Box 3000, Boulder, CO 80307-3000 (United States)

    2017-03-01

    How and where are coronal loops rooted in the solar lower atmosphere? The details of the magnetic environment and its evolution at the footpoints of coronal loops are crucial to understanding the processes of mass and energy supply to the solar corona. To address the above question, we use high-resolution line-of-sight magnetic field data from the Imaging Magnetograph eXperiment instrument on the Sunrise balloon-borne observatory and coronal observations from the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory of an emerging active region. We find that the coronal loops are often rooted at the locations with minor small-scale but persistent opposite-polarity magnetic elements very close to the larger dominant polarity. These opposite-polarity small-scale elements continually interact with the dominant polarity underlying the coronal loop through flux cancellation. At these locations we detect small inverse Y-shaped jets in chromospheric Ca ii H images obtained from the Sunrise Filter Imager during the flux cancellation. Our results indicate that magnetic flux cancellation and reconnection at the base of coronal loops due to mixed polarity fields might be a crucial feature for the supply of mass and energy into the corona.

  18. Recommended revised sections to line focus solar central power systems

    Energy Technology Data Exchange (ETDEWEB)

    1978-10-18

    The design requirements, subsystem characteristics, environmental requirements, and cost and performance evaluation techniques are defined for the Line Focus Solar Central Power Systems. Specific passages revised are enumerated. (LEW)

  19. Small Footprint Solar/Wind-powered CASTNET System Dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — In this Research Effort “Small Footprint Solar/Wind-Powered CASTNET System” there are two data sets. One data set contains atmospheric concentration measurements, at...

  20. The Design of Concentrated Solar Power Plants for Dubrovnik (Croatia

    Directory of Open Access Journals (Sweden)

    Huili Zhang

    2015-06-01

    Full Text Available The Croatian electricity demand exceeds domestic production and about 30 % of additional power is covered from imports. The Croatian government is planning to add domestic production capacity, using natural gas and coal as the main fuel. Due to the attractive solar irradiation in Croatia, these new projects offer the possibility to build these thermal power plants as hybrid plants by adding solar energy within the production. The present paper will investigate the potential of solar energy in the Southern Croatian region, and its possible contribution in a hybrid set-up. The paper assesses the required input data and presents a hybrid Concentrated Solar Power (CSP& design. The results demonstrate the potential of adding a CSP in a hybrid power plant in Southern Croatia.

  1. Lunar Surface Solar Electric Power System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose a concentrated photovoltaic electric power system for lunar operations called C-Lite Lunar. The novel technology produces a near-term solar array system...

  2. Research notes : solar powered markers not up to challenge.

    Science.gov (United States)

    2008-06-01

    ODOT performed preliminary tests on eight different models of solar powered raised pavement markers. These included environmental tests (extreme temperatures, immersion), optical performance tests, and observation tests. Federal Highway Administratio...

  3. Telecommunications equipment power supply in the Arctic by means of solar panels

    Science.gov (United States)

    Terekhin, Vladimir; Lagunov, Alexey

    2016-09-01

    Development of the Arctic region is one of the priorities in the Russian Federation. Amongst other things, a reliable telecommunications infrastructure in the Arctic is required. Petrol and diesel generators are traditionally employed but their use has considerable environmental impact. Solar panels can be used as an alternative power source. The electricity generated will be sufficient to supply small-sized telecommunications equipment with total the power of over 80 watts. An installation consisting of the solar modules, a charge controller, batteries, an inverter and load was designed. Tests were conducted at Cape Desire of the Novaya Zemlya (island). The solar panels provided in excess of 80 W from 7 a.m. to 11 p.m. The batteries charge during this time was sufficient to provide the power supply for the communication equipment during the night, from 11 p.m. to 7 a.m. The maximum value of 638 W of the power generation was observed at 3 p.m. The minimum value of 46 W was at 4 a.m. The solar modules thus can be used during the polar day to power the telecommunications equipment.

  4. Heat Transfer Phenomena in Concentrating Solar Power Systems.

    Energy Technology Data Exchange (ETDEWEB)

    Armijo, Kenneth Miguel; Shinde, Subhash L.

    2016-11-01

    Concentrating solar power (CSP) utilizes solar thermal energy to drive a thermal power cycle for the generation of electricity. CSP systems are facilitated as large, centralized power plants , such as power towers and trough systems, to take advantage of ec onomies of scale through dispatchable thermal energy storage, which is a principle advantage over other energy generation systems . Additionally, the combination of large solar concentration ratios with high solar conversion efficiencies provides a strong o pportunity of employment of specific power cycles such as the Brayton gas cycle that utilizes super critical fluids such as supercritical carbon dioxide (s CO 2 ) , compared to other sola r - fossil hybrid power plants. A comprehensive thermal - fluids examination is provided by this work of various heat transfer phenomena evident in CSP technologies. These include sub - systems and heat transfer fundamental phenomena evident within CSP systems , which include s receivers, heat transfer fluids (HTFs), thermal storage me dia and system designs , thermodynamic power block systems/components, as well as high - temperature materials. This work provides literature reviews, trade studies, and phenomenological comparisons of heat transfer media (HTM) and components and systems, all for promotion of high performance and efficient CSP systems. In addition, f urther investigations are also conducted that provide advanced heat transfer modeling approaches for gas - particle receiver systems , as well as performance/efficiency enhancement re commendations, particularly for solarized supercritical power systems .

  5. Solar power satellite life-cycle energy recovery consideration

    Science.gov (United States)

    Weingartner, S.; Blumenberg, J.

    The construction, in-orbit installation and maintenance of a solar power satellite (SPS) will demand large amounts of energy. As a minimum requirement for an energy effective power satellite it is asked that this amount of energy be recovered. The energy effectiveness in this sense resulting in a positive net energy balance is a prerequisite for cost-effective power satellite. This paper concentrates on life-cycle energy recovery instead on monetary aspects. The trade-offs between various power generation systems (different types of solar cells, solar dynamic), various construction and installation strategies (using terrestrial or extra-terrestrial resources) and the expected/required lifetime of the SPS are reviewed. The presented work is based on a 2-year study performed at the Technical University of Munich. The study showed that the main energy which is needed to make a solar power satellite a reality is required for the production of the solar power components (up to 65%), especially for the solar cell production. Whereas transport into orbit accounts in the order of 20% and the receiving station on earth (rectenna) requires about 15% of the total energy investment. The energetic amortization time, i.e. the time the SPS has to be operational to give back the amount of energy which was needed for its production installation and operation, is about two years.

  6. Solar power satellite—Life-cycle energy recovery considerations

    Science.gov (United States)

    Weingartner, S.; Blumenberg, J.

    1995-05-01

    The construction, in-orbit installation and maintenance of a solar power satellite (SPS) will demand large amounts of energy. As a minimum requirement for an energy effective power satellite it is asked that this amount of energy be recovered. The energy effectiveness in this sense resulting in a positive net energy balance is a prerequisite for a cost-effective power satellite. This paper concentrates on life-cycle energy recovery instead of monetary aspects. The trade-offs between various power generation systems (different types of solar cells, solar dynamic), various construction and installation strategies (using terrestrial or extra-terrestrial resources) and the expected/required lifetime of the SPS are reviewed. The presented work is based on a 2-year study performed at the Technical University of Munich. The study showed that the main energy which is needed to make a solar power satellite a reality is required for the production of the solar power plant components (up to 65%), especially for the solar cell production. Whereas transport into orbit accounts in the order of 20% and the receiving station on Earth (rectenna) requires in the order of 15% of the total energy investment. The energetic amortization time, i.e. the time the SPS has to be operational to give back the amount of energy which was needed for its production, installation and operation, is in the order of two years.

  7. A Charge Controller Design For Solar Power System

    Directory of Open Access Journals (Sweden)

    Nandar Oo

    2015-08-01

    Full Text Available This paper presents the solar charge controller circuit for controlling the overcharging and discharging from solar panel. This circuit regulates the charging of the battery in a solar system by monitoring battery voltage and switching the solar or other power source off when the battery reaches a preset voltage. This circuit is low voltages disconnect circuit. A charge controller circuit can increase battery life by preventing over-charging which can cause loss of electrolyte. The flow chart is also provided.

  8. Designing High Efficient Solar Powered OLED Lighting Systems

    DEFF Research Database (Denmark)

    Ploug, Rasmus Overgaard; Poulsen, Peter Behrensdorff; Thorsteinsson, Sune

    2016-01-01

    for the 10 Wp version. Furthermore, we present measurements of state-of-the-art commercial available OLED with regards to the luminous flux, luminous efficacy, luminance homogeneity, temperature dependency and IV characteristic of the OLED panels. In addition, solar powered OLED product concepts are proposed.......OLEDs used in solar powered lighting applications is a market of the future. This paper reports the development of electronic Three-Port-Converters for PV OLED product integration in the low-power area respectively for 1-10 Wp and 10-50 Wp with a peak efficiency of 97% at 1.8 W of PV power...

  9. Utilizing Solar Power Technologies for On-Orbit Propellant Production

    Science.gov (United States)

    Fikes, John C.; Howell, Joe T.; Henley, Mark W.

    2006-01-01

    The cost of access to space beyond low Earth orbit may be reduced if vehicles can refuel in orbit. The cost of access to low Earth orbit may also be reduced by launching oxygen and hydrogen propellants in the form of water. To achieve this reduction in costs of access to low Earth orbit and beyond, a propellant depot is considered that electrolyzes water in orbit, then condenses and stores cryogenic oxygen and hydrogen. Power requirements for such a depot require Solar Power Satellite technologies. A propellant depot utilizing solar power technologies is discussed in this paper. The depot will be deployed in a 400 km circular equatorial orbit. It receives tanks of water launched into a lower orbit from Earth, converts the water to liquid hydrogen and oxygen, and stores up to 500 metric tons of cryogenic propellants. This requires a power system that is comparable to a large Solar Power Satellite capable of several 100 kW of energy. Power is supplied by a pair of solar arrays mounted perpendicular to the orbital plane, which rotates once per orbit to track the Sun. The majority of the power is used to run the electrolysis system. Thermal control is maintained by body-mounted radiators; these also provide some shielding against orbital debris. The propellant stored in the depot can support transportation from low Earth orbit to geostationary Earth orbit, the Moon, LaGrange points, Mars, etc. Emphasis is placed on the Water-Ice to Cryogen propellant production facility. A very high power system is required for cracking (electrolyzing) the water and condensing and refrigerating the resulting oxygen and hydrogen. For a propellant production rate of 500 metric tons (1,100,000 pounds) per year, an average electrical power supply of 100 s of kW is required. To make the most efficient use of space solar power, electrolysis is performed only during the portion of the orbit that the Depot is in sunlight, so roughly twice this power level is needed for operations in sunlight

  10. Design approach for solar cell and battery of a persistent solar powered GPS tracker

    Science.gov (United States)

    Sahraei, Nasim; Watson, Sterling M.; Pennes, Anthony; Marius Peters, Ian; Buonassisi, Tonio

    2017-08-01

    Sensors with wireless communication can be powered by photovoltaic (PV) devices. However, using solar power requires thoughtful design of the power system, as well as a careful management of the power consumption, especially for devices with cellular communication (because of their higher power consumption). A design approach can minimize system size, weight, and/or cost, while maximizing device performance (data transmission rate and persistence). In this contribution, we describe our design approach for a small form-factor, solar-powered GPS tracker with cellular communication. We evaluate the power consumption of the device in different stages of operation. Combining measured power consumption and the calculated energy-yield of a solar cell, we estimate the battery capacity and solar cell area required for 5 years of continuous operation. We evaluate trade-offs between PV and battery size by simulating the battery state of charge. The data show a trade-off between battery capacity and solar-cell area for given target data transmission rate and persistence. We use this analysis to determine the combination of solar panel area and battery capacity for a given application and the data transmission rate that results in minimum cost or total weight of the system.

  11. High Temperature Surface Parameters for Solar Power

    National Research Council Canada - National Science Library

    Butler, C. F; Jenkins, R. J; Rudkin, R. L; Laughridge, F. I

    1960-01-01

    ... at a given distance from the sun. Thermal conversion efficiencies with a concentration ratio of 50 have been computed for each surface when exposed to solar radiation at the Earth's mean orbital radius...

  12. Parabolic Trough Solar Power for Competitive U.S. Markets

    International Nuclear Information System (INIS)

    Price, Henry W.

    1998-01-01

    Nine parabolic trough power plants located in the California Mojave Desert represent the only commercial development of large-scale solar power plants to date. Although all nine plants continue to operate today, no new solar power plants have been completed since 1990. Over the last several years, the parabolic trough industry has focused much of its efforts on international market opportunities. Although the power market in developing countries appears to offer a number of opportunities for parabolic trough technologies due to high growth and the availability of special financial incentives for renewables, these markets are also plagued with many difficulties for developers. In recent years, there has been some renewed interest in the U.S. domestic power market as a result of an emerging green market and green pricing incentives. Unfortunately, many of these market opportunities and incentives focus on smaller, more modular technologies (such as photovoltaics or wind power), and as a result they tend to exclude or are of minimum long-term benefit to large-scale concentrating solar power technologies. This paper looks at what is necessary for large-scale parabolic trough solar power plants to compete with state-of-the-art fossil power technology in a competitive U.S. power market

  13. Modelling extensive solar power production in urban and rural areas

    OpenAIRE

    Elfving, Gustav; Jansson, Emil

    2017-01-01

    Renewable energy sources, in form of solar power, is a growing source of energy. Not only at an industry level but also at a commercial level. Grid-connected, building-applied solar power has increased rapidly and as the implementation of solar energy grows, so does the importance of being able to evaluate locations that are of interest of installations with respect to its potential production and its impact on the electrical grid. In this thesis the energy production for different future sce...

  14. Solar mirrors characterization for concentrating solar power technology

    OpenAIRE

    Contino, Alessandro Patrizio

    2012-01-01

    The increasing availability on the market of different types of solar reflectors such as: polymeric film mirrors, aluminum mirrors and thin glass mirrors, together with: the lack of available norms in this area, and a valid methodology to compare the performances of the candidate reflectors; highlights the necessity to conduct a more detailed analysis on these new technologies. The objective of the present work is to suggest a valuable method to compare the reflectance performance of mirro...

  15. Solar Power for Near Sun, High-Temperature Missions

    Science.gov (United States)

    Landis, Geoffrey A.

    2008-01-01

    Existing solar cells lose performance at the high temperatures encountered in Mercury orbit and inward toward the sun. For future missions designed to probe environments close to the sun, it is desirable to develop array technologies for high temperature and high light intensity. Approaches to solar array design for near-sun missions include modifying the terms governing temperature of the cell and the efficiency at elevated temperature, or use of techniques to reduce the incident solar energy to limit operating temperature. An additional problem is found in missions that involve a range of intensities, such as the Solar Probe + mission, which ranges from a starting distance of 1 AU from the sun to a minimum distance of 9.5 solar radii, or 0.044 AU. During the mission, the solar intensity ranges from one to about 500 times AM0. This requires a power system to operate over nearly three orders of magnitude of incident intensity.

  16. Shuttle Topography Data Inform Solar Power Analysis

    Science.gov (United States)

    2013-01-01

    The next time you flip on a light switch, there s a chance that you could be benefitting from data originally acquired during the Space Shuttle Program. An effort spearheaded by Jet Propulsion Laboratory (JPL) and the National Geospatial-Intelligence Agency (NGA) in 2000 put together the first near-global elevation map of the Earth ever assembled, which has found use in everything from 3D terrain maps to models that inform solar power production. For the project, called the Shuttle Radar Topography Mission (SRTM), engineers at JPL designed a 60-meter mast that was fitted onto Shuttle Endeavour. Once deployed in space, an antenna attached to the end of the mast worked in combination with another antenna on the shuttle to simultaneously collect data from two perspectives. Just as having two eyes makes depth perception possible, the SRTM data sets could be combined to form an accurate picture of the Earth s surface elevations, the first hight-detail, near-global elevation map ever assembled. What made SRTM unique was not just its surface mapping capabilities but the completeness of the data it acquired. Over the course of 11 days, the shuttle orbited the Earth nearly 180 times, covering everything between the 60deg north and 54deg south latitudes, or roughly 80 percent of the world s total landmass. Of that targeted land area, 95 percent was mapped at least twice, and 24 percent was mapped at least four times. Following several years of processing, NASA released the data to the public in partnership with NGA. Robert Crippen, a member of the SRTM science team, says that the data have proven useful in a variety of fields. "Satellites have produced vast amounts of remote sensing data, which over the years have been mostly two-dimensional. But the Earth s surface is three-dimensional. Detailed topographic data give us the means to visualize and analyze remote sensing data in their natural three-dimensional structure, facilitating a greater understanding of the features

  17. Mini Solar and Sea Current Power Generation System

    Science.gov (United States)

    Almenhali, Abdulrahman; Alshamsi, Hatem; Aljunaibi, Yaser; Almussabi, Dheyab; Alshehhi, Ahmed; Hilal, Hassan Bu

    2017-07-01

    The power demand in United Arab Emirates is increased so that there is a consistent power cut in our region. This is because of high power consumption by factories and also due to less availability of conventional energy resources. Electricity is most needed facility for the human being. All the conventional energy resources are depleting day by day. So we have to shift from conventional to non-conventional energy resources. In this the combination of two energy resources is takes place i.e. wind and solar energy. This process reviles the sustainable energy resources without damaging the nature. We can give uninterrupted power by using hybrid energy system. Basically this system involves the integration of two energy system that will give continuous power. Solar panels are used for converting solar energy and wind turbines are used for converting wind energy into electricity. This electrical power can utilize for various purpose. Generation of electricity will be takes place at affordable cost. This paper deals with the generation of electricity by using two sources combine which leads to generate electricity with affordable cost without damaging the nature balance. The purpose of this project was to design a portable and low cost power system that combines both sea current electric turbine and solar electric technologies. This system will be designed in efforts to develop a power solution for remote locations or use it as another source of green power.

  18. The prospects for cost competitive solar PV power

    International Nuclear Information System (INIS)

    Reichelstein, Stefan; Yorston, Michael

    2013-01-01

    New solar Photovoltaic (PV) installations have grown globally at a rapid pace in recent years. We provide a comprehensive assessment of the cost competitiveness of this electric power source. Based on data available for the second half of 2011, we conclude that utility-scale PV installations are not yet cost competitive with fossil fuel power plants. In contrast, commercial-scale installations have already attained cost parity in the sense that the generating cost of power from solar PV is comparable to the retail electricity prices that commercial users pay, at least in certain parts of the U.S. This conclusion is shown to depend crucially on both the current federal tax subsidies for solar power and an ideal geographic location for the solar installation. Projecting recent industry trends into the future, we estimate that utility-scale solar PV facilities are on track to become cost competitive by the end of this decade. Furthermore, commercial-scale installations could reach “grid parity” in about ten years, if the current federal tax incentives for solar power were to expire at that point. - Highlights: ► Assessment of the cost competitiveness of new solar Photovoltaic (PV) installations. ► Utility-scale PV installations are not yet cost competitive with fossil fuel power plants. ► Commercial-scale installations have already attained cost parity in certain parts of the U.S. ► Utility-scale solar PV facilities are on track to become cost competitive by the end of this decade

  19. Brownfields City of Houston Solar Project: Solar Power Analysis and Design Specifications

    Science.gov (United States)

    This document details the scope of work elements completed in support of this project, as well as recommendations for next steps towards solar project development and power purchase agreement negotiation and finalization.

  20. Possibilities for retrofitting of the existing thermal electric power plants using solar power technologies

    International Nuclear Information System (INIS)

    Matjanov, Erkinjon K.; Abduganieva, Farogat A.; Aminov, Zarif Z.

    2012-01-01

    Full text: Total installed electric power output of the existing thermal electric power plants in Uzbekistan is reaches 12 GW. Thermal electric power plants, working on organic fuel, produce around 88 % of the electricity in the country. The emission coefficient of CO 2 gases is 620 gram/kwph. Average electric efficiency of the thermal electric power plants is 32.1 %. The mentioned above data certifies, that the existing thermal electric power plants of Uzbekistan are physically and morally aged and they need to be retrofitted. Retrofitting of the existing thermal electric power plants can be done by several ways such as via including gas turbine toppings, by using solar technologies, etc. Solar thermal power is a relatively new technology which has already shown its enormous promise. With few environmental impacts and a massive resource, it offers a comparable opportunity to the sunniest Uzbekistan. Solar thermal power uses direct sunlight, so it must be sited in regions with high direct solar radiation. In many regions, one square km of land is enough to generate as much as 100-120 GWh of electricity per year using the solar thermal technology. This is equivalent to the annual production of a 50 MW conventional coal or gas-fired mid-load power plant. Solar thermal power plants can be designed for solar-only or for hybrid operation. Producing electricity from the energy in the sun's rays is a straightforward process: direct solar radiation can be concentrated and collected by a range of Concentrating Solar Power technologies to provide medium- to high temperature heat. This heat is then used to operate a conventional power cycle, for example through a steam turbine or a Stirling engine. Solar heat collected during the day can also be stored in liquid or solid media such as molten salts, ceramics, concrete or, in the future, phase-changing salt mixtures. At night, it can be extracted from the storage medium thereby continuing turbine operation. Currently, the

  1. A Remote Power Management Strategy for the Solar Energy Powered Bicycle

    Directory of Open Access Journals (Sweden)

    Chung-Hsing Chao

    2011-12-01

    Full Text Available In this paper, a solar energy powered bicycle by a wireless sensor network (WSN far-end network monitoring solar energy to transfer the electrical energy storage and the effectiveness analysis is proposed. In order to achieve this goal, an embarked ZigBee by a solar-powered bicycle the far-end wireless network supervisory system is setup. Experimental results prove that our prototype, the solar energy powered bicycle, can manage the solar energy for charging two Lead-Acid batteries pack. As a result, the user by the wireless network in parking period knows the data on the amount of immediate solar radiation, the degree of illumination, the ambient temperature, and electrical energy storage capacity information by the internet interface.

  2. Investigation of solar photovoltaic module power output by various models

    International Nuclear Information System (INIS)

    Jakhrani, A.Q.; Othman, A.K.; Rigit, A.R.H.; Baini, R.

    2012-01-01

    This paper aims to investigate the power output of a solar photovoltaic module by various models and to formulate a suitable model for predicting the performance of solar photovoltaic modules. The model was used to correct the configurations of solar photovoltaic systems for sustainable power supply. Different types of models namely the efficiency, power, fill factor and current-voltage characteristic curve models have been reviewed. It was found that the examined models predicted a 40% yield of the rated power in cloudy weather conditions and up to 80% in clear skies. The models performed well in terms of electrical efficiency in cloudy days if the influence of low irradiance were incorporated. Both analytical and numerical methods were employed in the formulation of improved model which gave +- 2% error when compared with the rated power output of solar photovoltaic module. The proposed model is more practical in terms of number of variables used and acceptable performance in humid atmospheres. Therefore, it could be useful for the estimation of power output of the solar photovoltaic systems in Sarawak region. (author)

  3. A solar powered wireless computer mouse: industrial design concepts

    NARCIS (Netherlands)

    Reich, N.H.; Veefkind, M.; van Sark, W.G.J.H.M.; Alsema, E.A.; Turkenburg, W.C.; Silvester, S.

    2009-01-01

    A solar powered wireless computer mouse (SPM) was chosen to serve as a case study for the evaluation and optimization of industrial design processes of photovoltaic (PV) powered consumer systems. As the design process requires expert knowledge in various technical fields, we assessed and compared

  4. The Potential for Low-Cost Concentrating Solar Power Systems

    International Nuclear Information System (INIS)

    Price, Henry W.; Carpenter, Stephen

    1999-01-01

    Concern over the possibility of global climate change as a result of anthropogenic greenhouse gas buildup in the atmosphere is resulting in increased interest in renewable energy technologies. The World Bank recently sponsored a study to determine whether solar thermal power plants can achieve cost parity with conventional power plants. The paper reviews the conclusions of that study

  5. Combined solar photovoltaic and hydroelectric pumped storage power plant

    International Nuclear Information System (INIS)

    Gzraryan, R.V.

    2009-01-01

    Combined model of solar photovoltaic and pumped storage stations aimed at power supply for 40 rural houses are considered. The electric circuits of station and their acting regularities are developed and submitted. The both generation curve of photovoltaic station and load curve of electrical customer are considered. The power of hydraulic unit, pumping unit and photovoltaic station are calculated

  6. Livestock water pumping with wind and solar power

    Science.gov (United States)

    Recent developments in pumping technologies have allowed for efficient use of renewable energies like wind and solar to power new pumps for remote water pumping. A helical type, positive displacement pump was developed a few years ago and recently modified to accept input from a variable power sourc...

  7. Making Ultraviolet Spectro-Polarimetry Polarization Measurements with the MSFC Solar Ultraviolet Magnetograph Sounding Rocket

    Science.gov (United States)

    West, Edward; Cirtain, Jonathan; Kobayashi, Ken; Davis, John; Gary, Allen

    2011-01-01

    This paper will describe the Marshall Space Flight Center's Solar Ultraviolet Magnetograph Investigation (SUMI) sounding rocket program. This paper will concentrate on SUMI's VUV optics, and discuss their spectral, spatial and polarization characteristics. While SUMI's first flight (7/30/2010) met all of its mission success criteria, there are several areas that will be improved for its second and third flights. This paper will emphasize the MgII linear polarization measurements and describe the changes that will be made to the sounding rocket and how those changes will improve the scientific data acquired by SUMI.

  8. Space-based solar power generation: staged scenario

    Energy Technology Data Exchange (ETDEWEB)

    Glaser, P.E. [Arthur D. Little, Inc., Cambridge, MA (United States); Davidson, F.P. [Massachusetts Inst. of Technology, Macro-Engineering Research Group, Cambridge, MA (United States); Csigi, K.I. [ERIC International, Cambridge, MA (United States)

    1998-06-01

    Despite forecasts of increased global energy demand and warnings of environmental degradation associated with fossil fuel use, the idea of solar power satellites (SPS) generating power for microwave transmission to the Earth`s surface, has met widespread opposition or simply apathy. The authors urge a staged approach to the ultimate goal of developing SPS technology and infrastructure to meet global energy forecasts. The ``terracing`` idea means that technologies applicable to SPS will be developed to meet existing or planned projects to known scientific and economic value. A forty year growth plan for the ``terraced`` evolution of the solar power satellite is set out to illustrate this idea. (UK)

  9. Solar power from space: the worldwide grid of the future

    International Nuclear Information System (INIS)

    Anon.

    2000-01-01

    Recent interest in the feasibility and prospects for generating large amounts of electricity from space-based solar power systems is reviewed. The interest is generated by reports which suggest that sun-surfacing solar arrays in stationary earth orbit at an altitude 22,300 miles would not only be unaffected by the Earth's day-night cycle, cloud cover and atmospheric dust, but would also receive some eight times as much sunlight as solar collectors at the Earth's surface. The prediction is that relevant technology will be perfected to the point where by the middle of the 21. century a large share of the world's demand for electricity will be met by a series of very large space-based solar photovoltaic arrays. Several billion watts of power could be beamed to the Earth at microwave radio frequencies for collection by wide area rectifying ground antennas for conversion to electricity via transmitters connected to the photovoltaic arrays. A chronological account of development of this concept of beaming solar power from space shows that the idea has been around since the 1880s, gaining more and more credibility with each advance in space science . The moon, too, has been suggested as an ideal site for developing large-scale solar power systems that beam microwave energy to Earth. The lunar soil could supply silicon to build solar arrays, and metals such as iron and aluminum, for support structures and electric wiring. NASA is actively pursuing this line of inquiry, especially since all the problems involved with solar energy generation on earth, are absent on the moon.While a breakthrough is not imminent, the significant progress achieved to date in demonstrating the feasibility of wireless power transmission from space provides good reason for continuing to pursue this line of investigation

  10. 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).

  11. Solar Powered Automobile Interior Climate Control System

    Science.gov (United States)

    Howard, Richard T. (Inventor)

    2003-01-01

    There is provided a climate control system for a parked vehicle that includes a solar panel, thermostatic switch, fans, and thermoelectric coolers. The solar panel can serve as the sole source of electricity for the system. The system affords convenient installation and removal by including solar panels that are removably attached to the exterior of a vehicle. A connecting wire electrically connects the solar panels to a housing that is removably mounted to a partially opened window on the vehicle. The thermostatic switch, fans, and thermoelectric coolers are included within the housing. The thermostatic switch alternates the direction of the current flow through the thermoelectric coolers to selectively heat or cool the interior of the vehicle. The interior surface of the thermoelectric coolers are in contact with interior heat sinks that have air circulated across them by an interior fan. Similarly, the exterior surface of the thermoelectric coolers are in contact with exterior heat sinks that have air circulated across them by an exterior fan.

  12. Occurrence frequencies of polar mesosphere summer echoes observed at 69° N during a full solar cycle

    Science.gov (United States)

    Latteck, R.; Bremer, J.

    2013-07-01

    Polar mesosphere summer echoes (PMSE) are strong enhancements of received signal power at very high radar frequencies occurring at altitudes between about 80 and 95 km at polar latitudes during summer. PMSE are caused by inhomogeneities in the electron density of the radar Bragg scale within the plasma of the cold summer mesopause region in the presence of negatively charged ice particles. Thus the occurrence of PMSE contains information about mesospheric temperature and water vapour content but also depends on the ionisation due to solar wave radiation and precipitating high energetic particles. Continuous and homogeneous observations of PMSE have been done on the North-Norwegian island Andøya (69.3° N, 16.0° E) from 1999 until 2008 using the ALWIN VHF radar at 53.5 MHz. In 2009 the Leibniz-Institute of Atmospheric Physics in Kühlungsborn, Germany (IAP) started the installation of the Middle Atmosphere Alomar Radar System (MAARSY) at the same location. The observation of mesospheric echoes could be continued in spring 2010 starting with an initial stage of expansion of MAARSY and is carried out with the completed installation of the radar since May 2011. Since both the ALWIN radar and MAARSY are calibrated, the received echo strength of PMSE from 14 yr of mesospheric observations could be converted to absolute signal power. Occurrence frequencies based on different common thresholds of PMSE echo strength were used for investigations of the solar and geomagnetic control of the PMSE as well as of possible long-term changes. The PMSE are positively correlated with the solar Lyman α radiation and the geomagnetic activity. The occurrence frequencies of the PMSE show slightly positive trends but with marginal significance levels.

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

    Science.gov (United States)

    Novosel, Urška; Avsec, Jurij

    2017-07-01

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

  14. Long-Term Modeling of Solar Energy: Analysis of Concentrating Solar Power (CSP) and PV Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yabei; Smith, Steven J.

    2007-08-16

    This report presents an overview of research conducted on solar energy technologies and their implementation in the ObjECTS framework. The topics covered include financing assumptions and selected issues related to the integration of concentrating thermal solar power (CSP) and photovoltaics PV technologies into the electric grid. A review of methodologies for calculating the levelized energy cost of capital-intensive technologies is presented, along with sensitivity tests illustrating how the cost of a solar plant would vary depending on financing assumptions. An analysis of the integration of a hybrid concentrating thermal solar power (CSP) system into the electric system is conducted. Finally a failure statistics analysis for PV plants illustrates the central role of solar irradiance uncertainty in determining PV grid integration characteristics.

  15. Solar radiation for sea-water desalination and electric power generation via vacuum solar collectors

    International Nuclear Information System (INIS)

    Mottinelli, L.; Reali, M.; El-Nashar, A.M.; Giusiano, F.; Vigotti, R.

    1996-01-01

    The present report concerns the energetic potential of vacuum solar which are rather versatile and efficient devices for converting solar energy into thermal energy. Two main energetic applications have been analysed: the first one for a solar sea water desalination plant which has been operated in Abu Dhabi for the past ten years, the other for a conceptual solar thermoelectric-power plant having a fair thermodynamic efficiency (15-20%). A simple technology for the manufacture of vacuum solar collectors in a standard mechanical shop is being developed in collaboration between ENEL Sp A (DSR-CRIS, Milano) and WED (Abu Dhabi). Such technology should have an important economy-saving potential per se and would also make repair and substitution operations simple enough for the actual operators of the vacuum solar collector system without any need of external assistance. The technic-operative-economical features of the Abu Dhabi solar desalination plant suggest that the use novel simplified vacuum solar collectors could have a considerable technic economical potential. The analysis of the conceptual solar thermo-electric-power plant focuses on its general layout and singles out key technological issues which ought to be addressed in an overall feasibility study. 5 figs., 3 tabs

  16. Space-based solar power conversion and delivery systems study

    Science.gov (United States)

    1976-01-01

    Even at reduced rates of growth, the demand for electric power is expected to more than triple between now and 1995, and to triple again over the period 1995-2020. Without the development of new power sources and advanced transmission technologies, it may not be possible to supply electric energy at prices that are conductive to generalized economic welfare. Solar power is renewable and its conversion and transmission from space may be advantageous. The goal of this study is to assess the economic merit of space-based photovoltaic systems for power generation and a power relay satellite for power transmission. In this study, satellite solar power generation and transmission systems, as represented by current configurations of the Satellite Solar Station (SSPS) and the Power Relay Satellite (PRS), are compared with current and future terrestrial power generation and transmission systems to determine their technical and economic suitability for meeting power demands in the period of 1990 and beyond while meeting ever-increasing environmental and social constraints.

  17. Economic analysis of power generation from floating solar chimney power plant

    International Nuclear Information System (INIS)

    Zhou, Xinping; Yang, Jiakuan; Xiao, Bo; Wang, Fen

    2009-01-01

    Solar chimney thermal power technology that has a long life span is a promising large-scale solar power generating technology. This paper performs economic analysis of power generation from floating solar chimney power plant (FSCPP) by analyzing cash flows during the whole service period of a 100 MW plant. Cash flows are influenced by many factors including investment, operation and maintenance cost, life span, payback period, inflation rate, minimum attractive rate of return, non-returnable subsidy rate, interest rate of loans, sale price of electricity, income tax rate and whether additional revenue generated by carbon credits is included or not. Financial incentives and additional revenue generated by carbon credits can accelerate the development of the FSCPP. Sensitivity analysis to examine the effects of the factors on cash flows of a 100 MW FSCPP is performed in detail. The results show that the minimum price for obtaining minimum attractive rate of return (MARR) of 8% reaches 0.83 yuan (kWh) -1 under financial incentives including loans at a low interest rate of 2% and free income tax. Comparisons of economics of the FSCPP and reinforced concrete solar chimney power plant or solar photovoltaic plant are also performed by analyzing their cash flows. It is concluded that FSCPP is in reality more economical than reinforced concrete solar chimney power plant (RCSCPP) or solar photovoltaic plant (SPVP) with the same power capacity. (author)

  18. Solar Power System Source Versus Generator/PHCN Energy ...

    African Journals Online (AJOL)

    It was assumed that the power supply to the estate from PHCN was an average of 14 Hours a day while the remaining 10 hours had power supplied from the generator. The cost analysis for the two alternatives showed that the solar system required at least N 2,343,714,496:00 to supply power to the estate for a 25 year ...

  19. Solar photovoltaic power generation system and understanding of green energy

    International Nuclear Information System (INIS)

    Yoo, Chun Sik

    2004-03-01

    This book introduces sunlight generation system and green energy, which includes new and renewable energy such as photovoltaic power generation, solar thermal, wind power, bio energy, waste energy, geothermal energy, ocean energy and fuel cell photovoltaic industry like summary, technology trend, market trend, development strategy of the industry in Korea, and other countries, design of photovoltaic power generation system supporting policy and related business of new and renewable energy.

  20. Concentrated solar power in the built environment

    Science.gov (United States)

    Montenon, Alaric C.; Fylaktos, Nestor; Montagnino, Fabio; Paredes, Filippo; Papanicolas, Costas N.

    2017-06-01

    Solar concentration systems are usually deployed in large open spaces for electricity generation; they are rarely used to address the pressing energy needs of the built environment sector. Fresnel technology offers interesting and challenging CSP energy pathways suitable for the built environment, due to its relatively light weight (system into the HVAC (Heating, Ventilation, and Air Conditioning) system of a recently constructed office & laboratory building, the Novel Technologies Laboratory (NTL). The multi-generative system will support cooling, heating and hot water production feeding the system of the NTL building, as a demonstration project, part of the STS-MED program (Small Scale Thermal Solar District Units for Mediterranean Communities) financed by the European Commission under the European Neighbourhood and Partnership Instrument (ENPI), CBCMED program.

  1. Parametric cost model for solar space power and DIPS systems

    International Nuclear Information System (INIS)

    Meisl, C.J.

    1993-01-01

    A detailed cost model has been developed to parametrically determine the program development and production cost of (1) photovoltaic, (2) solar dynamic and (3) dynamic isotope (DIPS) space power systems. The model is applicable in the net electrical power range of 3 to 300 kWe for solar power, and 0.5 to 10 kWe for DIPS. Application of the cost model allows spacecraft or space-based power system architecture and design trade studies or budgetary forecasting and cost benefit analyses. The cost model considers all major power subsystems (i.e., power generation, power conversion, energy storage, thermal management, and power management/distribution/control). It also considers system cost effects such as integration, testing, management, etc. The cost breakdown structure, model assumptions, ground rules, bases, Cost Estimation Relationship (CER) format and rationale are presented, and the application of the cost model to 100-kWe solar space power plants and to a 1.0-kWe DIPS are demonstrated

  2. Solar thermal electric power generation - an attractive option for Pakistan

    International Nuclear Information System (INIS)

    Khan, N.A

    1999-01-01

    Solar Thermal Energy is being successfully used for production of electricity in few developed countries for more than 10 years. In solar Electric Generating Systems high temperature is generated by concentrating solar energy on black absorber pipe in evacuated glass tubes. This heat is absorbed and transported with the help of high temperature oil in to highly insulated heat exchanger storage tanks. They are subsequently used to produce steam that generates power through steam turbines as in standard thermal power plants. Various components involved in Solar thermal field have been developed at the Solar Systems Laboratory of College of EME, NUST Rawalpindi. It is considered as a cost effective alternate for power generation. The research has been partially sponsored by Ministry of Science and Technology under its Public Sector Development Program (PSDP) in (1996-1998). Parabolic mirror design, fabrication, polishing, installation, solar tracking, absorber pipe, glass tubes, steam generation al have been developed. This paper will cover the details of indigenous technological break through made in this direction. (author)

  3. GPP Webinar: Market Outlook and Innovations in Wind and Solar Power

    Science.gov (United States)

    Green Power Partnership webinar reviewing the state of the renewable energy industry as a whole, with a focus on wind and solar power and exploring recent marketplace innovations in wind and solar power and renewable energy purchases.

  4. A Polar Fuzzy Control Scheme for Hybrid Power System Using Vehicle-To-Grid Technique

    Directory of Open Access Journals (Sweden)

    Mohammed Elsayed Lotfy

    2017-07-01

    Full Text Available A novel polar fuzzy (PF control approach for a hybrid power system is proposed in this research. The proposed control scheme remedies the issues of system frequency and the continuity of demand supply caused by renewable sources’ uncertainties. The hybrid power system consists of a wind turbine generator (WTG, solar photovoltaics (PV, a solar thermal power generator (STPG, a diesel engine generator (DEG, an aqua-electrolyzer (AE, an ultra-capacitor (UC, a fuel-cell (FC, and a flywheel (FW. Furthermore, due to the high cost of the battery energy storage system (BESS, a new idea of vehicle-to-grid (V2G control is applied to use the battery of the electric vehicle (EV as equivalent to large-scale energy storage units instead of small batteries to improve the frequency stability of the system. In addition, EV customers’ convenience is taken into account. A minimal-order observer is used to estimate the supply error. Then, the area control error (ACE signal is calculated in terms of the estimated supply error and the frequency deviation. ACE is considered in the frequency domain. Two PF approaches are utilized in the intended system. The mission of each controller is to mitigate one frequency component of ACE. The responsibility for ACE compensation is shared among all parts of the system according to their speed of response. The performance of the proposed control scheme is compared to the conventional fuzzy logic control (FLC. The effectiveness and robustness of the proposed control technique are verified by numerical simulations under various scenarios.

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

    Science.gov (United States)

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

    1979-01-01

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

  6. Comparison of solar pond concepts for electrical power generation

    Energy Technology Data Exchange (ETDEWEB)

    Drumheller, K; Duffy, J B; Harling, O K; Knutsen, C A; McKinnon, M A; Peterson, P L; Shaffer, L H; Styris, D L; Zaworski, R

    1975-10-01

    The objectives of this study were to: (1) Identify the various solar pond concepts for electric power generation, including but not limited to: (a) nonconvective salt gradient solar pond, (b) ponds with various plastic or other membranes at suitable locations to minimize or eliminate convection, (c) ponds which are totally or partially gelled to reduce or eliminate convection, and (d) shallow convecting ponds; (2) analyze and compare the performance of these various concepts; and (3) estimate the pond cost and overall power plant system cost for each concept assuming the nonconvective gradient salt pond as the base case. The approach includes a preliminary design of several power plant systems based on solar pond concepts, and performance and economic evaluation based on these preliminary designs. (WDM)

  7. Energy Decisions: Is Solar Power the Solution?

    Science.gov (United States)

    Childress, Vincent W.

    2011-01-01

    People around the world are concerned about affordable energy. It is needed to power the global economy. Petroleum-based transportation and coal-fired power plants are economic prime movers fueling the global economy, but coal and gasoline are also the leading sources of air pollution. Both of these sources produce greenhouse gases and toxins.…

  8. A Comparative Study of Magnetic Fields in the Solar Photosphere and Chromosphere at Low and Polar Latitudes

    Science.gov (United States)

    Patrikeeva, Irina; Petrie, G.

    2009-05-01

    The SOLIS Vector-Spectromagnetograph produces full-disk line-of-sight (LOS) magnetic flux images deriving from both photospheric and chromospheric layers on a daily basis. We investigate key properties of the magnetic field in these two layers using more than five years of VSM data. We find from near-equatorial measurements that the East-West inclination angle of most photospheric fields is about 12°, while chromospheric fields expand in all directions to a significant degree. Using a simple stereoscopic inversion we find evidence that photospheric polar fields are also nearly radial, but that during 2008 the chromospheric field in the south pole was expanding super-radially. We obtain a spatially-resolved polar photospheric flux distribution up to 80° latitude whose strength increases poleward approximately as cosine(colatitude) to the power 9-10. This distribution would give a polar field strength of 5-6 G. These results have implications for future synoptic map construction and global modeling. This work is carried out through the National Solar Observatory Research Experiences for Undergraduate (REU) site program, which is co-funded by the Department of Defense in partnership with the National Science Foundation REU Program.

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

    Energy Technology Data Exchange (ETDEWEB)

    Braun, Gerald W.

    1980-06-01

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

  10. A heat receiver design for solar dynamic space power systems

    Science.gov (United States)

    Baker, Karl W.; Dustin, Miles O.; Crane, Roger

    1990-01-01

    An advanced heat pipe receiver designed for a solar dynamic space power system is described. The power system consists of a solar concentrator, solar heat receiver, Stirling heat engine, linear alternator and waste heat radiator. The solar concentrator focuses the sun's energy into a heat receiver. The engine and alternator convert a portion of this energy to electric power and the remaining heat is rejected by a waste heat radiator. Primary liquid metal heat pipes transport heat energy to the Stirling engine. Thermal energy storage allows this power system to operate during the shade portion of an orbit. Lithium fluoride/calcium fluoride eutectic is the thermal energy storage material. Thermal energy storage canisters are attached to the midsection of each heat pipe. The primary heat pipes pass through a secondary vapor cavity heat pipe near the engine and receiver interface. The secondary vapor cavity heat pipe serves three important functions. First, it smooths out hot spots in the solar cavity and provides even distribution of heat to the engine. Second, the event of a heat pipe failure, the secondary heat pipe cavity can efficiently transfer heat from other operating primary heat pipes to the engine heat exchanger of the defunct heat pipe. Third, the secondary heat pipe vapor cavity reduces temperature drops caused by heat flow into the engine. This unique design provides a high level of reliability and performance.

  11. WAGO IPCs manage energy on unique solar-powered boat

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2010-07-15

    This article described WAGO's contribution to the world's largest solar-powered boat, the Turanor PlanetSolar, a catamaran research vessel that was developed for solar power research. The boat has over 500 square metres of photovoltaic (PV) panels and 11 tons of batteries, including the 388 V lithium ion (NCA) battery. WAGO provided three 758 Series IPCs with control functionality and electrical components. The IPCs control charging for 3 batteries and 10 Drivetek Maximum Power Pick Trackers by way of 13 CAN buscouplers. The high-end DC/DC converters improve the solar absorption of the PV panels, which are fixed and mounted on the deck. For dependability in severe marine environments, WAGO's electrical components feature gas-tight connections that are vibration and thermal-cycling resistant. The Turanor accommodates a crew of four and has no gasoline back-ups for steering or propulsion. In 2011, the Turanor will embark on the first solar-powered circumnavigation of the globe by any means of transport. 1 fig.

  12. Solar Array Power Conditioning for a Spinning Satellite

    Science.gov (United States)

    De Luca, Antonio; Chirulli, Giovanni

    2008-09-01

    The conditioning of the output power from a solar array can mainly be achieved by the adoption of DET or MPPT based architecture. There are several factors that can orientate the choice of the system designer towards one solution or the other; some of them maybe inherent to the mission derived requirements (Illumination levels, EMC cleanliness, etc.), others come directly from a careful assessment of performances and losses of both power conditioner and solar array.Definition of the criteria on which basis the final choice is justified is important as they have to guarantee a clear determination of the available versus the required power in all those mission conditions identifiable as design drivers for the overall satellite system both in terms of mass and costs.Such criteria cannot just be simple theoretical enunciations of principles; nor the meticulous definition of them on a case by case basis for different types of missions as neither option gives a guarantee of being conclusive.The aim of this paper is then to suggest assessment steps and guidelines that can be considered generically valid for any mission case, starting from the exposition of the trade off activity performed in order to choose the power conditioning solution for a spinning satellite having unregulated power bus architecture. Calculations and numerical simulations have been made in order to establish the needed solar array surface in case of adoption of a DET or MPPT solution, taking into account temperature and illumination levels on the solar cells, as well as power losses and inefficiencies from the solar generator to the main power bus, in different mission phases. Particular attention has been taken in order to correctly evaluate the thermal effects on the rest of the spacecraft as function of the adopted power system regulation.

  13. Deployable Propulsion, Power and Communications Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, L.; Carr, J.; Boyd, D.

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication.

  14. ANALYSING SOLAR-WIND HYBRID POWER GENERATING SYSTEM

    Directory of Open Access Journals (Sweden)

    Mustafa ENGİN

    2005-02-01

    Full Text Available In this paper, a solar-wind hybrid power generating, system that will be used for security lighting was designed. Hybrid system was installed and solar cells, wind turbine, battery bank, charge regulators and inverter performance values were measured through the whole year. Using measured values of overall system efficiency, reliability, demanded energy cost per kWh were calculated, and percentage of generated energy according to resources were defined. We also include in the paper a discussion of new strategies to improve hybrid power generating system performance and demanded energy cost per kWh.

  15. Solar chimney power generation project - The case for Botswana

    International Nuclear Information System (INIS)

    Ketlogetswe, Clever; Seabe, Omphemetse O.; Fiszdon, Jerzy K.

    2008-01-01

    Import of a huge proportion of electrical energy from the Southern African Power Pool, and the geographical location and population distribution of Botswana stimulated the need to consider renewable energy as an alternative to imported power. The paper describes a systematic experimental study on a mini-solar chimney system. Particular attention is given to measurements of air velocity, temperature and solar radiation. The results for the selected 5 and 6 clear days of October and November, respectively, are presented. These results enable the relationship between average insolation, temperature difference and velocity for selected clear days to be discussed. (author)

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

    Science.gov (United States)

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

    2010-01-01

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

  17. Lightweight Phase-Change Material For Solar Power

    Science.gov (United States)

    Stark, Philip

    1993-01-01

    Lightweight panels containing phase-change materials developed for use as heat-storage elements of compact, lightweight, advanced solar dynamic power system. During high insolation, heat stored in panels via latent heat of fusion of phase-change material; during low insolation, heat withdrawn from panels. Storage elements consist mainly of porous carbon-fiber structures imbued with germanium. Developed for use aboard space station in orbit around Earth, also adapted to lightweight, compact, portable solar-power systems for use on Earth.

  18. Italy trials solar-thermal power plant

    Science.gov (United States)

    Cartlidge, Edwin

    2008-08-01

    It was in the Sicilian port of Syracuse that in 213 BC the Greek mathematician Archimedes was reputed to have torched an invading Roman fleet by concentrating the Sun's rays onto the enemy ships using large mirrors. Now, on a site very close to where Archimedes set up his putative solar weapon, engineers are building an array of parabolic mirrors to convert the Sun's energy into electricity. It is claimed that the technology, which uses molten salt to transfer energy to turbines, could be competitive with fossil fuels if it is deployed on a large enough scale in sunny climates.

  19. Concentrated Solar Power: Components and materials

    Directory of Open Access Journals (Sweden)

    Kribus A.

    2017-01-01

    Full Text Available CSP technologies are well developed and offer many advantages compared to other renewable energy options. They can also be very effective in many locations with high solar radiation around the world. However today they are less competitive than other technologies. Understanding the limitations, and identifying opportunities for improvements, requires a detailed analysis of the energy conversion processes, the needed components, and the required technologies for these plant components. Here we present the three main energy conversion steps in a CSP plant, the behavior and limitations of the technologies that are currently used in commercial CSP plants, and some directions for development of plant components that will offer better performance.

  20. Concentrated Solar Power: Components and materials

    Science.gov (United States)

    Kribus, A.

    2017-07-01

    CSP technologies are well developed and offer many advantages compared to other renewable energy options. They can also be very effective in many locations with high solar radiation around the world. However today they are less competitive than other technologies. Understanding the limitations, and identifying opportunities for improvements, requires a detailed analysis of the energy conversion processes, the needed components, and the required technologies for these plant components. Here we present the three main energy conversion steps in a CSP plant, the behavior and limitations of the technologies that are currently used in commercial CSP plants, and some directions for development of plant components that will offer better performance.

  1. Maximum-power-point tracking control of solar heating system

    KAUST Repository

    Huang, Bin-Juine

    2012-11-01

    The present study developed a maximum-power point tracking control (MPPT) technology for solar heating system to minimize the pumping power consumption at an optimal heat collection. The net solar energy gain Q net (=Q s-W p/η e) was experimentally found to be the cost function for MPPT with maximum point. The feedback tracking control system was developed to track the optimal Q net (denoted Q max). A tracking filter which was derived from the thermal analytical model of the solar heating system was used to determine the instantaneous tracking target Q max(t). The system transfer-function model of solar heating system was also derived experimentally using a step response test and used in the design of tracking feedback control system. The PI controller was designed for a tracking target Q max(t) with a quadratic time function. The MPPT control system was implemented using a microprocessor-based controller and the test results show good tracking performance with small tracking errors. It is seen that the average mass flow rate for the specific test periods in five different days is between 18.1 and 22.9kg/min with average pumping power between 77 and 140W, which is greatly reduced as compared to the standard flow rate at 31kg/min and pumping power 450W which is based on the flow rate 0.02kg/sm 2 defined in the ANSI/ASHRAE 93-1986 Standard and the total collector area 25.9m 2. The average net solar heat collected Q net is between 8.62 and 14.1kW depending on weather condition. The MPPT control of solar heating system has been verified to be able to minimize the pumping energy consumption with optimal solar heat collection. © 2012 Elsevier Ltd.

  2. Solar energy thermally powered electrical generating system

    Science.gov (United States)

    Owens, William R. (Inventor)

    1989-01-01

    A thermally powered electrical generating system for use in a space vehicle is disclosed. The rate of storage in a thermal energy storage medium is controlled by varying the rate of generation and dissipation of electrical energy in a thermally powered electrical generating system which is powered from heat stored in the thermal energy storage medium without exceeding a maximum quantity of heat. A control system (10) varies the rate at which electrical energy is generated by the electrical generating system and the rate at which electrical energy is consumed by a variable parasitic electrical load to cause storage of an amount of thermal energy in the thermal energy storage system at the end of a period of insolation which is sufficient to satisfy the scheduled demand for electrical power to be generated during the next period of eclipse. The control system is based upon Kalman filter theory.

  3. Solar power generation in a rural region

    International Nuclear Information System (INIS)

    1991-01-01

    The book contains the papers discussions and results of a German/Senegalese seminar on photovoltaic power generation in rural regions of Senegal which was held in Dakar on 19-23 November 1990. (HP) [de

  4. Air emissions due to wind and solar power.

    Science.gov (United States)

    Katzenstein, Warren; Apt, Jay

    2009-01-15

    Renewables portfolio standards (RPS) encourage large-scale deployment of wind and solar electric power. Their power output varies rapidly, even when several sites are added together. In many locations, natural gas generators are the lowest cost resource available to compensate for this variability, and must ramp up and down quickly to keep the grid stable, affecting their emissions of NOx and CO2. We model a wind or solar photovoltaic plus gas system using measured 1-min time-resolved emissions and heat rate data from two types of natural gas generators, and power data from four wind plants and one solar plant. Over a wide range of renewable penetration, we find CO2 emissions achieve approximately 80% of the emissions reductions expected if the power fluctuations caused no additional emissions. Using steam injection, gas generators achieve only 30-50% of expected NOx emissions reductions, and with dry control NOx emissions increase substantially. We quantify the interaction between state RPSs and NOx constraints, finding that states with substantial RPSs could see significant upward pressure on NOx permit prices, if the gas turbines we modeled are representative of the plants used to mitigate wind and solar power variability.

  5. Solar powered wrist worn acquisition system for continuous photoplethysmogram monitoring.

    Science.gov (United States)

    Dieffenderfer, James P; Beppler, Eric; Novak, Tristan; Whitmire, Eric; Jayakumar, Rochana; Randall, Clive; Qu, Weiguo; Rajagopalan, Ramakrishnan; Bozkurt, Alper

    2014-01-01

    We present a solar-powered, wireless, wrist-worn platform for continuous monitoring of physiological and environmental parameters during the activities of daily life. In this study, we demonstrate the capability to produce photoplethysmogram (PPG) signals using this platform. To adhere to a low power budget for solar-powering, a 574 nm green light source is used where the PPG from the radial artery would be obtained with minimal signal conditioning. The system incorporates two monocrystalline solar cells to charge the onboard 20 mAh lithium polymer battery. Bluetooth Low Energy (BLE) is used to tether the device to a smartphone that makes the phone an access point to a dedicated server for long term continuous storage of data. Two power management schemes have been proposed depending on the availability of solar energy. In low light situations, if the battery is low, the device obtains a 5-second PPG waveform every minute to consume an average power of 0.57 mW. In scenarios where the battery is at a sustainable voltage, the device is set to enter its normal 30 Hz acquisition mode, consuming around 13.7 mW. We also present our efforts towards improving the charge storage capacity of our on-board super-capacitor.

  6. Freshwater generation from a solar chimney power plant

    International Nuclear Information System (INIS)

    Ming, Tingzhen; Gong, Tingrui; Richter, Renaud K. de; Liu, Wei; Koonsrisuk, Atit

    2016-01-01

    Highlights: • A solar chimney system for freshwater generation is proposed. • Precipitation of nine cities in China is analyzed. • Effectiveness of this device between the arid region and the humid region is given. • The amount of potable water produced by this device is remarkable. - Abstract: A modified solar chimney power plant is presented which is not only a solar thermal system able to achieve output power but also is able to extract freshwater from the air. This solar chimney power plant has no greenhouse canopy which is replaced by a collector made of black tubes around the chimney to warm the water and air. The effectiveness of this engineering structure is analyzed in comparison to natural precipitation at nine cities in China; one-dimensional compressible flow and heat transfer mathematical model has been developed to describe the moist air which cools down along the chimney and condenses above the lifting condensation level. The recovery of water is a partial duplication of natural atmospheric convection processes because of the unstable environment lapse rate. The results showed that there is often a high-strength positive correlation between the natural precipitation and the water production by this modified solar chimney power plant in those cities, Water production by the device in the conditions of the study can produce up to 37.9 × 10 6 tons of water per year in Guangzhou, and 29.7 × 10 6 tons of water per year in Chengdu, the correlation coefficient is even up to 0.875. Moreover, this device is more efficient in arid regions, might increase the rainfalls and enhance the regional water cycle. The amount of potable water produced by this modified solar chimney power plant is remarkable and might be able to benefit to several millions of people.

  7. Solar power plant performance evaluation: simulation and experimental validation

    Science.gov (United States)

    Natsheh, E. M.; Albarbar, A.

    2012-05-01

    In this work the performance of solar power plant is evaluated based on a developed model comprise photovoltaic array, battery storage, 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 (MPPT) implementation. The outcome of the developed model are validated and supported by a case study carried out using operational 28.8kW grid-connected solar power plant located in central Manchester. Measurements were taken over 21 month's period; using hourly average irradiance and cell temperature. It was found that system degradation could be clearly monitored by determining the residual (the difference) between the output power predicted by the model and the actual measured power parameters. It was found that the residual exceeded the healthy threshold, 1.7kW, due to heavy snow in Manchester last winter. More important, the developed performance evaluation technique could be adopted to detect any other reasons that may degrade the performance of the P V panels such as shading and dirt. Repeatability and reliability of the developed system performance were validated during this period. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.

  8. Solar power plant performance evaluation: simulation and experimental validation

    International Nuclear Information System (INIS)

    Natsheh, E M; Albarbar, A

    2012-01-01

    In this work the performance of solar power plant is evaluated based on a developed model comprise photovoltaic array, battery storage, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P and O) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The outcome of the developed model are validated and supported by a case study carried out using operational 28.8kW grid-connected solar power plant located in central Manchester. Measurements were taken over 21 month's period; using hourly average irradiance and cell temperature. It was found that system degradation could be clearly monitored by determining the residual (the difference) between the output power predicted by the model and the actual measured power parameters. It was found that the residual exceeded the healthy threshold, 1.7kW, due to heavy snow in Manchester last winter. More important, the developed performance evaluation technique could be adopted to detect any other reasons that may degrade the performance of the P V panels such as shading and dirt. Repeatability and reliability of the developed system performance were validated during this period. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.

  9. High-Power Solar Electric Propulsion for Future NASA Missions

    Science.gov (United States)

    Manzella, David; Hack, Kurt

    2014-01-01

    NASA has sought to utilize high-power solar electric propulsion as means of improving the affordability of in-space transportation for almost 50 years. Early efforts focused on 25 to 50 kilowatt systems that could be used with the Space Shuttle, while later efforts focused on systems nearly an order of magnitude higher power that could be used with heavy lift launch vehicles. These efforts never left the concept development phase in part because the technology required was not sufficiently mature. Since 2012 the NASA Space Technology Mission Directorate has had a coordinated plan to mature the requisite solar array and electric propulsion technology needed to implement a 30 to 50 kilowatt solar electric propulsion technology demonstration mission. Multiple solar electric propulsion technology demonstration mission concepts have been developed based on these maturing technologies with recent efforts focusing on an Asteroid Redirect Robotic Mission. If implemented, the Asteroid Redirect Vehicle will form the basis for a capability that can be cost-effectively evolved over time to provide solar electric propulsion transportation for a range of follow-on mission applications at power levels in excess of 100 kilowatts.

  10. Solar-powered oxygen delivery: proof of concept.

    Science.gov (United States)

    Turnbull, H; Conroy, A; Opoka, R O; Namasopo, S; Kain, K C; Hawkes, M

    2016-05-01

    A resource-limited paediatric hospital in Uganda. Pneumonia is a leading cause of child mortality worldwide. Access to life-saving oxygen therapy is limited in many areas. We designed and implemented a solar-powered oxygen delivery system for the treatment of paediatric pneumonia. Proof-of-concept pilot study. A solar-powered oxygen delivery system was designed and piloted in a cohort of children with hypoxaemic illness. The system consisted of 25 × 80 W photovoltaic solar panels (daily output 7.5 kWh [range 3.8-9.7kWh]), 8 × 220 Ah batteries and a 300 W oxygen concentrator (output up to 5 l/min oxygen at 88% [±2%] purity). A series of 28 patients with hypoxaemia were treated with solar-powered oxygen. Immediate improvement in peripheral blood oxygen saturation was documented (median change +12% [range 5-15%], P oxygen and hospital discharge were respectively 7.5 h, 9.8 h, 44 h and 4 days. Solar energy can be used to concentrate oxygen from ambient air and oxygenate children with respiratory distress and hypoxaemia in a resource-limited setting.

  11. 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.

  12. Role of Concentrating Solar Power in Integrating Solar and Wind Energy: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Denholm, P.; Mehos, M.

    2015-06-03

    As wind and solar photovoltaics (PV) increase in penetration it is increasingly important to examine enabling technologies that can help integrate these resources at large scale. Concentrating solar power (CSP) when deployed with thermal energy storage (TES) can provide multiple services that can help integrate variable generation (VG) resources such as wind and PV. CSP with TES can provide firm, highly flexible capacity, reducing minimum generation constraints which limit penetration and results in curtailment. By acting as an enabling technology, CSP can complement PV and wind, substantially increasing their penetration in locations with adequate solar resource.

  13. Solar thermal and concentrated solar power barometer - EurObserv'ER - May 2012

    International Nuclear Information System (INIS)

    2012-05-01

    27545 MWth: the EU's solar thermal base to date at the end of 2011. After two years of sharp decline, the European solar thermal market is bottoming out. The EurObserv'ER survey findings are that the installation figure fell just 1.9% in comparison with 2010, giving a newly-installed collector area of 3.7 million m 2 . The concentrated solar power sector has been forging ahead alongside the heat production applications, and at the end of 2011 installed capacity passed the one gigawatt mark in Spain for the first time with 1157.2 MWe

  14. Deployable Propulsion and Power Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, Les; Carr, John

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. The Near Earth Asteroid (NEA) Scout reconnaissance mission will demonstrate solar sail propulsion on a 6U CubeSat interplanetary spacecraft and lay the groundwork for their future use in deep space science and exploration missions. Solar sails use sunlight to propel vehicles through space by reflecting solar photons from a large, mirror-like sail made of a lightweight, highly reflective material. This continuous photon pressure provides propellantless thrust, allowing for very high delta V maneuvers on long-duration, deep space exploration. Since reflected light produces thrust, solar sails require no onboard propellant. The Lightweight Integrated Solar Array and Transceiver (LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between power, communications, and GN&C (guidance navigation and control) subsystems. This restricts payload capability and limits the value of these low-cost satellites. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft. The NEA Scout mission, funded by NASA's Advanced Exploration Systems Program and managed by NASA MSFC, will use the solar sail as its primary propulsion system, allowing it to survey and image one or more NEA's of interest for possible future human exploration. NEA Scout uses a 6U cubesat (to be provided by NASA's Jet Propulsion Laboratory), an 86 sq m solar sail and will weigh less than 12 kilograms. NEA Scout will be launched on the first flight of the Space Launch System in 2018. Similar in concept

  15. Residential Solar Power and the Physics Teacher

    Science.gov (United States)

    Carpenter, David

    2007-10-01

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

  16. LOW POWER UPCONVERSION FOR SOLAR FUELS PHOTOCHEMISTRY

    Energy Technology Data Exchange (ETDEWEB)

    Castellano, Felix N. [Bowling Green State University

    2013-08-05

    Earth abundant copper(I) diimine complexes represent a renewable and economically feasible alternative to commonly used heavy metal containing chromophores. In the metal-to-ligand charge transfer (MLCT) excited state, copper(I) diimine complexes typically undergo a significant structural rearrangement, leading to molecules with large Stokes shifts and very short excited state lifetimes, thereby limiting their usefulness as sensitizers in bimolecular electron and triplet energy transfer reactions. Strategically placed bulky substituents on the coordinating phenanthroline ligands have proven useful in restricting the transiently produced excited state Jahn-Teller distortion, leading to longer-lived excited states. By combining bulky sec-butyl groups in the 2- and 9- positions with methyl groups in the 3-,4-, 7-, and 8- positions, a remarkably long-lived (2.8 μs in DCM) copper(I) bis-phenanthroline complex, [Cu(dsbtmp)2]+, has been synthesized and characterized. Unlike other copper(I) diimine complexes, [Cu(dsbtmp)2]+ also retains a μs lifetime in coordinating solvents such as acetonitrile and water as a result of the cooperative sterics inherent in the molecular design. Preliminary results on the use of this complex in hydrogen-forming homogeneous photocatalysis is presented. Photon upconversion based on sensitized triplet-triplet annihilation (TTA) represents a photochemical means to generate high-energy photons (or high-energy chemical products) from low-energy excitation, having potential applications in solar energy conversion and solar fuels producing devices. For the first time, synthetically facile and earth abundant Cu(I) MLCT sensitizers have been successfully incorporated into two distinct photochemical upconversion schemes, affording both red-to-green and orange-to-blue wavelength conversions. Preliminary results on aqueous-based photochemical upconversion as well as intramolecular Sn(IV) porphyrins containing axially coordinated aromatic hydrocarbon

  17. 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.

  18. Solar-powered turbocompressor heat pump system

    Science.gov (United States)

    Landerman, A.M.; Biancardi, F.R.; Melikian, G.; Meader, M.D.; Kepler, C.E.; Anderson, T.J.; Sitler, J.W.

    1982-08-12

    The turbocompressor comprises a power turbine and a compressor turbine having respective rotors and on a common shaft, rotatably supported by bearings. A first working fluid is supplied by a power loop and is expanded in the turbine. A second working fluid is compressed in the turbine and is circulated in a heat pump loop. A lubricant is mixed with the second working fluid but is excluded from the first working fluid. The bearings are cooled and lubricated by a system which circulates the second working fluid and the intermixed lubricant through the bearings. Such system includes a pump, a thermostatic expansion valve for expanding the working fluid into the space between the bearings, and a return conduit system for withdrawing the expanded working fluid after it passes through the bearings and for returning the working fluid to the evaporator. A shaft seal excludes the lubricant from the power turbine. The power loop includes a float operable by liquid working fluid in the condenser for controlling a recirculation valve so as to maintain a minimum liquid level in the condenser, while causing a feed pump to pump most of the working fluid into the vapor generator. The heat pump compressor loop includes a float in the condenser for operating and expansion valve to maintain a minimum liquid working fluid level in the condenser while causing most of the working fluid to be expanded into the evaporator.

  19. Designing high efficient solar powered lighting systems

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Thorsteinsson, Sune; Lindén, Johannes

    2016-01-01

    -Port-Converters respectively for 1-10Wp and 10-50 Wp with a peak efficiency of 97% at 1.8 W of PV power for the 10 Wp version. Furthermore, a modelling tool for L2L products has been developed and a laboratory for feeding in component data not available in the datasheets to the model is described....

  20. Sandwich module prototype progress for space solar power

    Science.gov (United States)

    Jaffe, Paul; Hodkin, Jason; Harrington, Forest; Person, Clark; Nurnberger, Michael; Nguyen, Bang; LaCava, Susie; Scheiman, Dave; Stewart, Grant; Han, Andrew; Hettwer, Ethan; Rhoades, Daniel

    2014-02-01

    Space solar power (SSP) has been broadly defined as the collection of solar energy in space and its wireless transmission for use on earth. This approach potentially gives the benefit of provision of baseload power while avoiding the losses due to the day/night cycle and tropospheric effects that are associated with terrestrial solar power. Proponents have contended that the implementation of such systems could offer energy security, environmental, and technological advantages to those who would undertake their development. Among recent implementations commonly proposed for SSP, the modular symmetrical concentrator (MSC) and other modular concepts have received considerable attention. Each employs an array of modules for performing conversion of concentrated sunlight into microwaves or laser beams for transmission to earth. While prototypes of such modules have been designed and developed previously by several groups, none have been subjected to the challenging conditions inherent to the space environment and the possible solar concentration levels in which an array of modules might be required to operate. The research described herein details our team's efforts in the development of photovoltaic arrays, power electronics, microwave conversion electronics, and antennas for microwave-based "sandwich" module prototypes. The implementation status and testing results of the prototypes are reviewed.

  1. Electrostatic protection of the Solar Power Satellite and rectenna

    Science.gov (United States)

    Freeman, J. W.; Few, A. A., Jr.; Reiff, P. H.; Cooke, D.; Bohannon, J.; Haymes, B.

    1979-01-01

    Several features of the interactions of the solar power satellite (SPS) with its space environment were examined theoretically. The voltages produced at various surfaces due to space plasmas and the plasma leakage currents through the kapton and sapphire solar cell blankets were calculated. At geosynchronous orbit, this parasitic power loss is only 0.7%, and is easily compensated by oversizing. At low-Earth orbit, the power loss is potentially much larger (3%), and anomalous arcing is expected for the EOTV high voltage negative surfaces. Preliminary results of a three dimensional self-consistent plasma and electric field computer program are presented, confirming the validity of the predictions made from the one dimensional models. Magnetic shielding of the satellite, to reduce the power drain and to protect the solar cells from energetic electron and plasma ion bombardment is considered. It is concluded that minor modifications can allow the SPS to operate safely and efficiently in its space environment. The SPS design employed in this study is the 1978 MSFC baseline design utilizing GaAs solar cells at CR-2 and an aluminum structure.

  2. Concentrating solar power: Still small but learning fast

    Science.gov (United States)

    Pitz-Paal, Robert

    2017-07-01

    Concentrating solar power had a difficult market start compared to other renewable technologies, leading to a total global capacity of only 5 GW today after more than a decade of deployment. A comprehensive global empirical study identifies distinct deployment phases, with high learning rates exceeding 25% over the past 5 years.

  3. Solar Power Tower Design Basis Document, Revision 0

    Energy Technology Data Exchange (ETDEWEB)

    ZAVOICO,ALEXIS B.

    2001-07-01

    This report contains the design basis for a generic molten-salt solar power tower. A solar power tower uses a field of tracking mirrors (heliostats) that redirect sunlight on to a centrally located receiver mounted on top a tower, which absorbs the concentrated sunlight. Molten nitrate salt, pumped from a tank at ground level, absorbs the sunlight, heating it up to 565 C. The heated salt flows back to ground level into another tank where it is stored, then pumped through a steam generator to produce steam and make electricity. This report establishes a set of criteria upon which the next generation of solar power towers will be designed. The report contains detailed criteria for each of the major systems: Collector System, Receiver System, Thermal Storage System, Steam Generator System, Master Control System, and Electric Heat Tracing System. The Electric Power Generation System and Balance of Plant discussions are limited to interface requirements. This design basis builds on the extensive experience gained from the Solar Two project and includes potential design innovations that will improve reliability and lower technical risk. This design basis document is a living document and contains several areas that require trade-studies and design analysis to fully complete the design basis. Project- and site-specific conditions and requirements will also resolve open To Be Determined issues.

  4. Flight of the loon : solar-powered boating

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2006-04-01

    Details of the first solar-powered, zero-emission boat to venture across the Trent-Severn waterway were presented. Called the 'Loon', the boat is now being manufactured for environmentally-conscious boaters around the world. The seating arrangement, pontoon design, and propulsion system were all designed to minimize impacts on the ecosystem. A prototype boat was built and tested in the summer of 2005 to determine the viability of the solar-powered boat, and a family trip down the waterway was completed in August. Results of the trip encouraged the inventor to raise capital and a suitable production facility. After several months of development, the first production boat was completed with many improvements to the original prototype. An entrepreneur from Belize was the first person to place an order after he discovered that most commercially-available solar-powered boats were higher-priced and less capable than the Loon. High gas prices and the detrimental effects of fuel exhaust in lakes have caused many people to become sensitive to the issues surrounding fuel use and pleasure boats. It was concluded that a storefront has recently been opened north of Orillia in order to sell the solar-powered craft. 3 figs.

  5. Research notes : solar powered navigational lighting system demonstration project.

    Science.gov (United States)

    2011-04-01

    ODOT will be installing a solar powered navigational lighting system on the AstoriaMegler Bridge as part of a pilot project approved by the Federal Highways Administration (FHWA). The coastal bridge is the connection across the Columbia River on U.S....

  6. Emerging US Space Launch, Trends and Space Solar Power

    Science.gov (United States)

    Zapata, Edgar

    2015-01-01

    Reviews the state of the art of emerging US space launch and spacecraft. Reviews the NASA budget ascontext, while providing example scenarios. Connects what has been learned in space systems commercial partnershipsto a potential path for consideration by the space solar power community.

  7. Design and Thermal Analysis of a Solar Powered Cold Storage ...

    African Journals Online (AJOL)

    Design and Thermal Analysis of a Solar Powered Cold Storage Ware-House Using a Phase- Change Material. ... of Nigeria of perishable agricultural products at different conservation temperatures corresponding to the solidification temperatures of phase change materials using cheap and abundant source of energy.

  8. Automated identification and tracking of polar-cap plasma patches at solar minimum

    Directory of Open Access Journals (Sweden)

    R. Burston

    2014-03-01

    Full Text Available A method of automatically identifying and tracking polar-cap plasma patches, utilising data inversion and feature-tracking methods, is presented. A well-established and widely used 4-D ionospheric imaging algorithm, the Multi-Instrument Data Assimilation System (MIDAS, inverts slant total electron content (TEC data from ground-based Global Navigation Satellite System (GNSS receivers to produce images of the free electron distribution in the polar-cap ionosphere. These are integrated to form vertical TEC maps. A flexible feature-tracking algorithm, TRACK, previously used extensively in meteorological storm-tracking studies is used to identify and track maxima in the resulting 2-D data fields. Various criteria are used to discriminate between genuine patches and "false-positive" maxima such as the continuously moving day-side maximum, which results from the Earth's rotation rather than plasma motion. Results for a 12-month period at solar minimum, when extensive validation data are available, are presented. The method identifies 71 separate structures consistent with patch motion during this time. The limitations of solar minimum and the consequent small number of patches make climatological inferences difficult, but the feasibility of the method for patches larger than approximately 500 km in scale is demonstrated and a larger study incorporating other parts of the solar cycle is warranted. Possible further optimisation of discrimination criteria, particularly regarding the definition of a patch in terms of its plasma concentration enhancement over the surrounding background, may improve results.

  9. Improved high temperature solar absorbers for use in Concentrating Solar Power central receiver applications.

    Energy Technology Data Exchange (ETDEWEB)

    Stechel, Ellen Beth; Ambrosini, Andrea; Hall, Aaron Christopher; Lambert, Timothy L.; Staiger, Chad Lynn; Bencomo, Marlene

    2010-09-01

    Concentrating solar power (CSP) systems use solar absorbers to convert the heat from sunlight to electric power. Increased operating temperatures are necessary to lower the cost of solar-generated electricity by improving efficiencies and reducing thermal energy storage costs. Durable new materials are needed to cope with operating temperatures >600 C. The current coating technology (Pyromark High Temperature paint) has a solar absorptance in excess of 0.95 but a thermal emittance greater than 0.8, which results in large thermal losses at high temperatures. In addition, because solar receivers operate in air, these coatings have long term stability issues that add to the operating costs of CSP facilities. Ideal absorbers must have high solar absorptance (>0.95) and low thermal emittance (<0.05) in the IR region, be stable in air, and be low-cost and readily manufacturable. We propose to utilize solution-based synthesis techniques to prepare intrinsic absorbers for use in central receiver applications.

  10. Performance of the Solar Two central receiver power plant

    Energy Technology Data Exchange (ETDEWEB)

    Prairie, M.R.; Pacheco, J.E.; Gilbert, R.L.; Reilly, H.E. [Sandia National Labs., Albuquerque, NM (United States); Speidel, P.J. [Shada Environmental Specialists, Inc., Huntington Beach, CA (United States); Kelly, B.D. [Bechtel Corp., San Francisco, CA (United States)

    1998-09-01

    Solar Two is a utility-led project to promote the commercialization of solar power towers by retrofitting the Solar One pilot plant from a water/steam-based system to a molten salt system. Solar Two is capable of producing 10 MW(e) net electricity with enough thermal storage capacity to operate the turbine for three hours after sunset. The plant was turned over to its operations and maintenance contractor in February 1998, marking transition from start-up to the test and evaluation phase. Solar Two has collected as much as 230 MWh thermal and generated as much as 72 MWh(e) gross electricity in one day. The plant has demonstrated dispatchability after dark, during clouds, and during sunshine hours. To date, Solar Two has collected thermal energy at a maximum rate of 39 MW(t) and generated gross electricity at a maximum rate of 11.1 MW(e). Important lessons have been learned in the areas of heat trace, valve selection, materials of construction, and steam generator design. Testing has begun in a number of areas relating to receiver performance, storage tank performance, salt chemistry, overnight thermal conditioning, electricity dispatching, performance monitoring and evaluation, availability tracking, and receiver controls.

  11. Software and codes for analysis of concentrating solar power technologies.

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Clifford Kuofei

    2008-12-01

    This report presents a review and evaluation of software and codes that have been used to support Sandia National Laboratories concentrating solar power (CSP) program. Additional software packages developed by other institutions and companies that can potentially improve Sandia's analysis capabilities in the CSP program are also evaluated. The software and codes are grouped according to specific CSP technologies: power tower systems, linear concentrator systems, and dish/engine systems. A description of each code is presented with regard to each specific CSP technology, along with details regarding availability, maintenance, and references. A summary of all the codes is then presented with recommendations regarding the use and retention of the codes. A description of probabilistic methods for uncertainty and sensitivity analyses of concentrating solar power technologies is also provided.

  12. High temperature helical tubular receiver for concentrating solar power system

    Science.gov (United States)

    Hossain, Nazmul

    In the field of conventional cleaner power generation technology, concentrating solar power systems have introduced remarkable opportunity. In a solar power tower, solar energy concentrated by the heliostats at a single point produces very high temperature. Falling solid particles or heat transfer fluid passing through that high temperature region absorbs heat to generate electricity. Increasing the residence time will result in more heat gain and increase efficiency. A novel design of solar receiver for both fluid and solid particle is approached in this paper which can increase residence time resulting in higher temperature gain in one cycle compared to conventional receivers. The helical tubular solar receiver placed at the focused sunlight region meets the higher outlet temperature and efficiency. A vertical tubular receiver is modeled and analyzed for single phase flow with molten salt as heat transfer fluid and alloy625 as heat transfer material. The result is compared to a journal paper of similar numerical and experimental setup for validating our modeling. New types of helical tubular solar receivers are modeled and analyzed with heat transfer fluid turbulent flow in single phase, and granular particle and air plug flow in multiphase to observe the temperature rise in one cyclic operation. The Discrete Ordinate radiation model is used for numerical analysis with simulation software Ansys Fluent 15.0. The Eulerian granular multiphase model is used for multiphase flow. Applying the same modeling parameters and boundary conditions, the results of vertical and helical receivers are compared. With a helical receiver, higher temperature gain of heat transfer fluid is achieved in one cycle for both single phase and multiphase flow compared to the vertical receiver. Performance is also observed by varying dimension of helical receiver.

  13. Effects of Power Tracking Algorithms on Lifetime of Power Electronic Devices Used in Solar Systems

    Directory of Open Access Journals (Sweden)

    Canras Batunlu

    2016-10-01

    Full Text Available In photovoltaic solar energy systems, power management algorithms (PMAs, usually called maximum power point tracking (MPPT algorithms, are widely used for extracting maximum available power at every point in time. However, tracking the maximum power has negative effects on the availability of solar energy systems. This is due, mainly, to the created disturbances and thermal stresses on the associated power electronic converters (PECs. This work investigates the effects of PMA on the lifetime consumption, thermal stresses and failures on DC-DC converters used in solar systems. Firstly theoretical analysis and modelling of photovoltaic solar systems including converter’s electro thermal characteristics were developed. Subsequently, experiments on photovoltaic solar systems were carried out using two different PMAs, namely, perturb and observe (P&O and incremental conductance (IC. Real-time data was collected, under different operating conditions, including thermal behavior using thermal imaging camera and dSPACE. Converters’ thermal cycling was found to be approximately 3 °C higher with the IC algorithm. The steady state temperature was 52.7 °C, for the IC while it was 42.6 °C for P&O. Although IC algorithm offers more accurate power management tool, it causes more severe thermal stresses which, in this study, has led to approximately 1.4 times greater life consumption compared to P&O.

  14. Polarization Characteristics of Zebra Patterns in Type IV Solar Radio Bursts

    Energy Technology Data Exchange (ETDEWEB)

    Kaneda, K.; Misawa, H.; Tsuchiya, F.; Obara, T. [Planetary Plasma and Atmospheric Research Center, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Iwai, K. [National Institute of Information and Communications Technology, 4-2-1, Nukui-Kitamachi, Koganei, Tokyo 184-8795 (Japan); Katoh, Y. [Department of Geophysics, Graduate School of Science, Tohoku University, Sendai, Miyagi 980-8578 (Japan); Masuda, S., E-mail: k.kaneda@pparc.gp.tohoku.ac.jp [Institute for Space—Earth Environmental Research, Nagoya University, Nagoya, Aichi 464-8601 (Japan)

    2017-06-10

    The polarization characteristics of zebra patterns (ZPs) in type IV solar bursts were studied. We analyzed 21 ZP events observed by the Assembly of Metric-band Aperture Telescope and Real-time Analysis System between 2010 and 2015 and identified the following characteristics: a degree of circular polarization (DCP) in the range of 0%–70%, a temporal delay of 0–70 ms between the two circularly polarized components (i.e., the right- and left-handed components), and dominant ordinary-mode emission in about 81% of the events. For most events, the relation between the dominant and delayed components could be interpreted in the framework of fundamental plasma emission and depolarization during propagation, though the values of DCP and delay were distributed across wide ranges. Furthermore, it was found that the DCP and delay were positively correlated (rank correlation coefficient R = 0.62). As a possible interpretation of this relationship, we considered a model based on depolarization due to reflections at sharp density boundaries assuming fundamental plasma emission. The model calculations of depolarization including multiple reflections and group delay during propagation in the inhomogeneous corona showed that the DCP and delay decreased as the number of reflections increased, which is consistent with the observational results. The dispersive polarization characteristics could be explained by the different numbers of reflections causing depolarization.

  15. Integration of Small Solar Tower Systems Into Distributed Power Islands

    International Nuclear Information System (INIS)

    Romero, M.; Marcos, M. J.; Tellez, F. M.; Blanco, M.; Fernandez, V.; Baonza, F.; Berger, S.

    1999-01-01

    One of the short-term priorities for renewable energies in Europe is their integration for local power supply into communities and energy islands (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-parks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leading to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begun. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The chief questions are whether solar towers can be redesigned for such distributed markets and the keys to their feasibility. This paper includes the design and performance analysis of a 1.36-MW plant and integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostats configuration and tower height. A practical application is analyzed for a shopping center with 85% power demand during day-time by using a hybrid solar tower and a gas turbine producing electricity and waste heat for hot water and heating and cooling of spaces. The operation mode proposed is covering night demand with power from the grid and solar-gas power island mode during 14 hours daytime with a maximum power production of 1.36 MW. (Author) 26 refs

  16. Integration of Small Solar tower Systems into Distributed Power Islands

    Energy Technology Data Exchange (ETDEWEB)

    Romero, M.; Marcos, M. J.; Tellez, F. M.; Blanco, M.; Fernandez, V.; Baonza, F.; Berger, S. [Ciemat, Madrid (Spain)

    2000-07-01

    One of the short-term priorities for renewable energies in Europe is their integration for local power supply into communities and energy islands (blocks of buildings, new neighborhoods in residential areas, shopping centers, hospitals, recreational areas, eco-paks, small rural areas or isolated ones such as islands or mountain communities). Following this strategy, the integration of small tower fields into so-called MIUS (Modular Integrated Utility Systems) is proposed. This application strongly influences field concepts leadings to modular multi-tower systems able to more closely track demand, meet reliability requirements with fewer megawatts of installed power and spread construction costs over time after output has begum. In addition, integration into single-cycle high-efficiency gas turbines plus waste-heat applications clearly increments the solar share. The chief questions are whether solar towers can be redesigned for such distributed markets and the keys to their feasibility. This paper includes the design and performance analysis of a 1.36-MW plant and integration in the MIUS system, as well as the expected cost of electricity and a sensitivity analysis of the small tower plant's performance with design parameters like heliostat configuration and tower height. A practical application is analyzed for a shopping center with 85% power demand during day-time by using a hybrid solar tower and a gas turbine producing electricity and waste heat for hot water and heating and cooling of spaces. The operation mode proposed is covering night demand with power from the grid and solar-gas power island mode during 14 hours daytime with a maximum power production of 1.36 MW. (Author) 26 refs.

  17. Energy and exergy analysis of solar power tower plants

    International Nuclear Information System (INIS)

    Xu Chao; Wang Zhifeng; Li Xin; Sun Feihu

    2011-01-01

    Establishing the renewable electricity contribution from solar thermal power systems based on energy analysis alone cannot legitimately be complete unless the exergy concept becomes a part of that analysis. This paper presents a theoretical framework for the energy analysis and exergy analysis of the solar power tower system using molten salt as the heat transfer fluid. Both the energy losses and exergy losses in each component and in the overall system are evaluated to identify the causes and locations of the thermodynamic imperfection. Several design parameters including the direct normal irradiation (DNI), the concentration ratio, and the type of power cycle are also tested to evaluate their effects on the energy and exergy performance. The results show that the maximum exergy loss occurs in the receiver system, followed by the heliostat field system, although main energy loss occurs in the power cycle system. The energy and exergy efficiencies of the receiver and the overall system can be increased by increasing the DNI and the concentration ratio, but that increment in the efficiencies varies with the values of DNI and the concentration ratio. It is also found that the overall energy and exergy efficiencies of the solar tower system can be increased to some extent by integrating advanced power cycles including reheat Rankine cycles and supercritical Rankine cycles. - Highlights: →We presented a theoretical framework for the energy and exergy analysis of the solar tower system. →We tested the effects of several design parameters on the energy and exergy performance. →The maximum exergy loss occurs in the receiver system, followed by the heliostat field system. →Integrating advanced power cycles leads to increases in the overall energy and exergy efficiencies.

  18. Solar Power System Evaluated for the Human Exploration of Mars

    Science.gov (United States)

    Kerslake, Thomas W.

    2000-01-01

    The electric power system is a crucial element of any mission for the human exploration of the Martian surface. The bulk of the power generated will be delivered to crew life support systems, extravehicular activity suits, robotic vehicles, and predeployed in situ resource utilization (ISRU) equipment. In one mission scenario, before the crew departs for Mars, the ISRU plant operates for 435 days producing liquefied methane and oxygen for ascent-stage propellants and water for crew life support. About 200 days after ISRU production is completed, the crew arrives for a 500-day surface stay. In this scenario, the power system must operate for a total of 1130 days (equivalent to 1100 Martian "sols"), providing 400 MW-hr of energy to the ISRU plant and up to 18 kW of daytime user power. A photovoltaic power-generation system with regenerative fuel cell (RFC) energy storage has been under study at the NASA Glenn Research Center at Lewis Field. The conceptual power system is dominated by the 4000- m2 class photovoltaic array that is deployed orthogonally as four tent structures, each approximately 5 m on a side and 100-m long. The structures are composed of composite members deployed by an articulating mast, an inflatable boom, or rover vehicles, and are subsequently anchored to the ground. Array panels consist of thin polymer membranes with thin-film solar cells. The array is divided into eight independent electrical sections with solar cell strings operating at 600 V. Energy storage is provided by regenerative fuel cells based on hydrogen-oxygen proton exchange membrane technology. Hydrogen and oxygen reactants are stored in gaseous form at 3000 psi, and the water produced is stored at 14.7 psi. The fuel cell operating temperature is maintained by a 40-m2 deployable pumped-fluid loop radiator that uses water as the working fluid. The power management and distribution (PMAD) architecture features eight independent, regulated 600-Vdc channels. Power management and

  19. SPS-ALPHA: The First Practical Solar Power Satellite via Arbitrarily Large PHased Array

    Data.gov (United States)

    National Aeronautics and Space Administration — SPS-ALPHA (Solar Power Satellite via Arbitrarily Large Phased Array) is a novel, bio-mimetic approach to the challenge of space solar power. If successful, this...

  20. Space power system utilizing Fresnel lenses for solar power and also thermal energy storage

    Science.gov (United States)

    Turner, R. H.

    1983-01-01

    A solar power plant suitable for earth orbits passing through Van Allen radiation belts is described. The solar-to-electricity conversion efficiency is estimated to be around 9 percent, and the expected power-to-weight ratio is competitive with photovoltaic arrays. The system is designed to be self-contained, to be indifferent to radiation belt exposures, store energy for periods when the orbiting system is in earth shadow (so that power generation is contant), have no moving parts and no working fluids, and be robust against micrometeorite attack. No electrical batteries are required.

  1. Textile solar light collectors based on models for polar bear hair

    Energy Technology Data Exchange (ETDEWEB)

    Bahners, Thomas; Schlosser, Uwe; Schollmeyer, Eckhard [Deutsches Textilforschungszentrum Nord-West e.V., Adlerstr. 1, D-47798 Krefeld (Germany); Gutmann, Rainer [Institut fuer Textilchemie und Chemiefasern, Koerschtalstr. 26, D-73770 Denkendorf (Germany)

    2008-12-15

    Concepts of technical fibers following models for the polar bear hair to be used for textile solar collectors are discussed. The approach to coat fibers with a thin layer into which fluorescent dyestuff was dispersed was studied experimentally. Modified fibers made of different polymers were characterized with respect to optical properties relevant for the bionic model. In the case of poly(methylmethacrylate) fibers, the envisaged effect could be achieved to high efficiency. The optical performance could be enhanced by ultrasonic dispersion of the dyestuff in the coating matrix. The effect is less significant in semi-crystalline fibers such as poly(ethylene terephthalate), which is attributed to diffuse scattering. (author)

  2. Deployable Propulsion, Power and Communication Systems for Solar System Exploration

    Science.gov (United States)

    Johnson, Les; Carr, John A.; Boyd, Darren

    2017-01-01

    NASA is developing thin-film based, deployable propulsion, power, and communication systems for small spacecraft that could provide a revolutionary new capability allowing small spacecraft exploration of the solar system. By leveraging recent advancements in thin films, photovoltaics, and miniaturized electronics, new mission-level capabilities will be enabled aboard lower-cost small spacecraft instead of their more expensive, traditional counterparts, enabling a new generation of frequent, inexpensive deep space missions. Specifically, thin-film technologies are allowing the development and use of solar sails for propulsion, small, lightweight photovoltaics for power, and omnidirectional antennas for communication. Like their name implies, solar sails 'sail' by reflecting sunlight from a large, lightweight reflective material that resembles the sails of 17th and 18th century ships and modern sloops. Instead of wind, the sail and the ship derive their thrust by reflecting solar photons. Solar sail technology has been discussed in the literature for quite some time, but it is only since 2010 that sails have been proven to work in space. Thin-film photovoltaics are revolutionizing the terrestrial power generation market and have been found to be suitable for medium-term use in the space environment. When mounted on the thin-film substrate, these photovoltaics can be packaged into very small volumes and used to generate significant power for small spacecraft. Finally, embedded antennas are being developed that can be adhered to thin-film substrates to provide lightweight, omnidirectional UHF and X-band coverage, increasing bandwidth or effective communication ranges for small spacecraft. Taken together, they may enable a host of new deep space destinations to be reached by a generation of spacecraft smaller and more capable than ever before.

  3. Designing high efficient solar powered lighting systems

    DEFF Research Database (Denmark)

    Poulsen, Peter Behrensdorff; Thorsteinsson, Sune; Lindén, Johannes

    2016-01-01

    Some major challenges in the development of L2L products is the lack of efficient converter electronics, modelling tools for dimensioning and furthermore, characterization facilities to support the successful development of the products. We report the development of 2 Three-Port-Converters respec......Some major challenges in the development of L2L products is the lack of efficient converter electronics, modelling tools for dimensioning and furthermore, characterization facilities to support the successful development of the products. We report the development of 2 Three-Port......-Converters respectively for 1-10Wp and 10-50 Wp with a peak efficiency of 97% at 1.8 W of PV power for the 10 Wp version. Furthermore, a modelling tool for L2L products has been developed and a laboratory for feeding in component data not available in the datasheets to the model is described....

  4. Solar thermal and concentrated solar power barometer - EurObserv'ER - May 2013

    International Nuclear Information System (INIS)

    2013-05-01

    The European concentrated solar power plant market is steeling itself for tough time ahead. The number of projects under construction is a pittance compared with 2012 that was an excellent year for installations (an additional 802.5 MW of capacity recorded). This drop is the result of the moratorium on renewable energy power plants introduced by the Spanish government. The European solar thermal market is hardly any more encouraging. EurObserv'ER holds that it slipped for the fourth year in a row (it dropped 5.5% between 2011 and 2012). The newly-installed solar thermal collector surface area in the EU now stands at 3.4 million m 2 , far short of its 2008 installation record of 4.6 million m 2

  5. Power Systems Evaluated for Solar Electric Propulsion Vehicles

    Science.gov (United States)

    Kerslake, Thomas W.; Gefert, Leon P.

    2000-01-01

    Solar electric propulsion (SEP) mission architectures are applicable to a wide range NASA missions including the robotic exploration of the outer planets in the next decade and the human exploration of Mars within the next 2 decades. SEP enables architectures that are very mass efficient with reasonable power levels (1-MW class) aerobrake and cryogenic upper-stage transportation technologies are utilized. In this architecture, the efficient SEP stage transfers the payload from low Earth orbit (LEO) High Energy Elliptical Parking Orbit (HEEPO) within a period of 6 to 12 months. highthrust, cryogenic upper stage and payload then separate from the SEP vehicle for injection to the planetary target, allowing for fast heliocentric trip times. This mission architecture offers a potential reduction in mass to LEO in comparison to alternative all-chemical nuclear propulsion schemes. Mass reductions may allow launch vehicle downsizing enable missions that would have been grounded because of cost constraints. The preceding figure illustrates a conceptual SEP stage design for a human Mars mission. Researchers at the NASA Glenn Research Center at Lewis Field designed conceptual SEP vehicle, conceived the mission architecture to use this vehicle, and analyzed the vehicle s performance. This SEP stage has a dry mass of 35 metric tons (MT), 40 MT of xenon propellant, and a photovoltaic array that spans 110 m, providing power to a cluster of eight 100-kW Hall thrusters. The stage can transfer an 80-MT payload and upper stage to the desired HEEPO. Preliminary packaging studies show this space-station-class SEP vehicle meets the proposed "Magnum" launch vehicle and volume requirements with considerable margin. An SEP vehicle for outer planetary missions, such as the Europa Mapper Mission, would be dramatically smaller than human Mars mission SEP stage. In this mission architecture, the SEP power system with the payload to provide spacecraft power throughout the mission. Several

  6. Orbital Space Solar Power Option for a Lunar Village

    Science.gov (United States)

    Johnson, Les

    2017-01-01

    One of the most significant challenges to the implementation of a continuously manned lunar base is power. During the lunar day (14 Earth days), it is conceptually simple to deploy solar arrays to generate the estimated 35 kilowatts of continuous power required. However, generating this level of power during the lunar night (also 14 Earth days) has been an extremely difficult problem to solve. Conventional solutions range from the requirement that the base be located at the lunar south pole so as to take advantage of the continuous sunshine available there to developing a space-qualified nuclear reactor and power plant to generate the needed energy. There is a third option: Use the soon-to-be-available Space Launch System to place a space based solar power station in lunar orbit that would beam the needed energy to the lunar base. Several detailed studies have been performed by NASA, universities and others looking at the lunar south pole for locating the base. The results are encouraging: by taking advantage of the moon's orbital tilt, large solar arrays can be deployed there to track the sun continuously and generate the power needed to sustain the base. The problem with this approach is inherent to its design: it will only work at the lunar south pole. There is no other site on the Moon with geometry favorable to generating continuous solar power. NASA has also considered the development of a compact fission reactor and power plant to generate the needed power, allowing the base to be sited anywhere on the Moon. The problem with this approach is that there are no space fission reactors available, none are being planned and the cost of developing one is prohibitively expensive. Using an orbiting space based solar power station to generate electrical power and beam it to a base sited anywhere on the moon should therefore be considered. The technology to collect sunlight, generate greater than the estimated 35 kilowatts of power, and beam it to the surface using

  7. Thermoeconomic optimization of a Kalina cycle for a central receiver concentrating solar power plant

    DEFF Research Database (Denmark)

    Modi, Anish; Kærn, Martin Ryhl; Andreasen, Jesper Graa

    2016-01-01

    Concentrating solar power plants use a number of reflecting mirrors to focus and convert the incident solar energy to heat, and a power cycle to convert this heat into electricity. This paper evaluates the use of a high temperature Kalina cycle for a central receiver concentrating solar power plant...... and the economic perspectives, the results suggest that it is not beneficial to use the Kalina cycle for high temperature concentrating solar power plants....

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

    Science.gov (United States)

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

    2015-06-01

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

  9. Power spectra trends in imaging polarimetry of outdoor solar illuminated scenes

    Science.gov (United States)

    Kupinski, Meredith; Chipman, Russell

    2016-05-01

    The 1=∫2 power law (where ∫ is spatial frequency) characterizes the spatial power spectrum of non-polarimetric images of outdoor scenes when averaged over an appropriately large ensemble. This empirical result has been repeatedly verified in diverse imaging applications. In this work we compare the ensemble-averaged power spectrum of radiance and polarized radiance images. Outdoor scenes have been imaged over the past three-years using JPL's Ground-based Multiangle SpectroPolarimetric Imager (Ground-MSPI)[1] at the University of Arizona (UA). Ground-MSPI is an eight-band spectropolarimetric camera mounted on a rotating gimbal to acquire pushbroom imagery of solar illuminated outdoor landscapes. This Ground-MSPI image library offers a unique opportunity to quantify the statistical trends between polarimetric and non-polarimetric measurements. From power spectrum analysis of 1,975 images in our collection we report that the magnitude of the 1=∫-exponent is lower for the polarized radiance image than the corresponding radiance image. This result quantifies the contrast mechanism difference for imaging polarimetry, indicates higher spatial frequency content in passive polarimetry of outdoor environments, and supports the assertion that polarimetry offers unique detection capabilities.

  10. A solar pond driven distillation and power production system

    Science.gov (United States)

    Johnson, D. H.; Leboeuf, C. M.; Waddington, D.

    In this paper a solar pond driven distillation and power production system is described. The storage layer of the solar pond serves as the holding tank for the concentrated brine effluent from the distillation process as well as the collector and storage medium for solar energy used to heat incoming salty river water. Steam from the distillation process expands through a turbine/generator combination to provide power for the water circulation and vacuum pumps of the system. Water from the surface mixed layer of the pond is used to condense the steam. The closely integrated distillation and power production system converts an incoming stream of brackish or saline water into an outlet stream of the required purity. Salt and power are also products of the system. A thermodynamic analysis of the energy and mass balances of the system has been performed and a performance model of the system has been developed. This has been used to size the system for the application of desalting saline tributaries of the Colorado River.

  11. SOLAR PHOTOVOLTAIC OUTPUT POWER FORECASTING USING BACK PROPAGATION NEURAL NETWORK

    Directory of Open Access Journals (Sweden)

    B. Jency Paulin

    2016-01-01

    Full Text Available Solar Energy is an important renewable and unlimited source of energy. Solar photovoltaic power forecasting, is an estimation of the expected power production, that help the grid operators to better manage the electric balance between power demand and supply. Neural network is a computational model that can predict new outcomes from past trends. The artificial neural network is used for photovoltaic plant energy forecasting. The output power for solar photovoltaic cell is predicted on hourly basis. In historical dataset collection process, two dataset was collected and used for analysis. The dataset was provided with three independent attributes and one dependent attributes. The implementation of Artificial Neural Network structure is done by Multilayer Perceptron (MLP and training procedure for neural network is done by error Back Propagation (BP. In order to train and test the neural network, the datasets are divided in the ratio 70:30. The accuracy of prediction can be done by using various error measurement criteria and the performance of neural network is to be noted.

  12. Maximizing Output Power of a Solar Panel via Combination of Sun Tracking and Maximum Power Point Tracking by Fuzzy Controllers

    Directory of Open Access Journals (Sweden)

    Mohsen Taherbaneh

    2010-01-01

    Full Text Available In applications with low-energy conversion efficiency, maximizing the output power improves the efficiency. The maximum output power of a solar panel depends on the environmental conditions and load profile. In this paper, a method based on simultaneous use of two fuzzy controllers is developed in order to maximize the generated output power of a solar panel in a photovoltaic system: fuzzy-based sun tracking and maximum power point tracking. The sun tracking is performed by changing the solar panel orientation in horizontal and vertical directions by two DC motors properly designed. A DC-DC converter is employed to track the solar panel maximum power point. In addition, the proposed system has the capability of the extraction of solar panel I-V curves. Experimental results present that the proposed fuzzy techniques result in increasing of power delivery from the solar panel, causing a reduction in size, weight, and cost of solar panels in photovoltaic systems.

  13. Saving assessment using the PERS in solar power towers

    International Nuclear Information System (INIS)

    Rodriguez-Sanchez, M.R.; Sanchez-Gonzalez, A.; Marugan-Cruz, C.; Santana, D.

    2014-01-01

    Highlights: • The lamination of the solar salt is avoided using the PERS and the main energy sink. • The PERS using salt pump as turbine saves 30–50% of the parasitic power. • The most appropriate configuration is a similar turbine three times one salt pump. • The payback period is around two years, and the economical savings from 1 to 4 M$. - Abstract: The improvement of the solar power tower using solar salt is one of the main goals of researchers. Any method or invention to improve the efficiency of this technology contributes to promote the renewable energies. The use of a Potential Energy Recovery System (PERS) in two different solar power tower plants of 20 and 100 MW has been analysed. The PERS is formed, at least, by one turbine, located at the hot salt pipe coming from the receiver. The turbine is engaged to the shaft of the feed pump, which raises the heat transfer fluid from the cold tank to the receiver. It reduces the parasitic power consumption of the plant, and increases its global efficiency. Different PERS configurations have been modelled. Based on an energetic and economic analysis, the optimal configuration is a geometrical similar turbine of three times the volume flow rate of one feed pump. The PERS has been proven to be a cost reductive and clean tool. For a 100 MW power plant of 30-year lifetime the investment cost is 1.26 M$ and the annual cash flow is 0.89 M$, while for a plant of 20 MW these values are 0.26 M$ and 0.19 M$, respectively

  14. 76 FR 69284 - Certain Integrated Solar Power Systems and Components Thereof: Notice of Institution of...

    Science.gov (United States)

    2011-11-08

    ... the United States after importation of certain integrated solar power systems and components thereof... certain integrated solar power systems and components thereof that infringe one or more of claims 6 and 10... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-811] Certain Integrated Solar Power...

  15. Solar power. [comparison of costs to wind, nuclear, coal, oil and gas

    Science.gov (United States)

    Walton, A. L.; Hall, Darwin C.

    1990-01-01

    This paper describes categories of solar technologies and identifies those that are economic. It compares the private costs of power from solar, wind, nuclear, coal, oil, and gas generators. In the southern United States, the private costs of building and generating electricity from new solar and wind power plants are less than the private cost of electricity from a new nuclear power plant. Solar power is more valuable than nuclear power since all solar power is available during peak and midpeak periods. Half of the power from nuclear generators is off-peak power and therefore is less valuable. Reliability is important in determining the value of wind and nuclear power. Damage from air pollution, when factored into the cost of power from fossil fuels, alters the cost comparison in favor of solar and wind power. Some policies are more effective at encouraging alternative energy technologies that pollute less and improve national security.

  16. Solar-Powered Desalination: A Modelling and Experimental Study

    Science.gov (United States)

    Leblanc, Jimmy; Andrews, John

    2007-10-01

    Water shortage is becoming one of the major problems worldwide. As such, desalination technologies have been implemented to meet growing demands for fresh water. Among the desalination technologies, thermal desalination, including multi stage flash (MSF) and multi effect evaporation (MEE), is the current leading desalination process. Reverse osmosis (RO) is also being increasingly used. Despite technological improvements, thermal desalination and reverse osmosis continue to be intensive fossil-fuel consumers and contribute to increased levels of greenhouse gases. As energy costs rise, thermal desalination by solar energy and/or low cost waste heat is likely to become increasingly attractive. As part of a project investigating the productive use of saline land and the development of sustainable desalination systems, the feasibility of producing potable water from seawater or brackish water using desalination systems powered by renewable energy in the form of low-temperature solar-thermal sources has been studied. A salinity-gradient solar pond and an evacuated tube solar collector system have been used as heat sources. Solar ponds combine solar energy collection with long-term storage and can provide reliable thermal energy at temperature ranges from 50 to 90 °C. A visual basic computer model of the different multi-stage flash desalination processes coupled with a salinity-gradient solar pond was developed to determine which process is preferable in regards to performance and greenhouse impact. The governing mathematical equations are derived from mass balances, heat energy balances, and heat transfer characteristics. Using the results from the modelling, a small-scale solar-powered desalination system, capable of producing up to 500 litres of fresh water per day, was designed and manufactured. This single-stage flash system consists of two main units: the heat supply and storage system and the flash desalination unit. Two different condenser heat exchanger

  17. Efficient Cells Cut the Cost of Solar Power

    Science.gov (United States)

    2013-01-01

    If you visit Glenn Research Center, you might encounter a photovoltaic (PV) array that looks unlike anything you've ever seen. In fact, what one would normally identify as the panel is actually a series of curved mirrors called solar concentrators, engineered to reflect sunlight rather than absorb it. These concentrators gather, intensify, and focus sun beams upward, aiming at a fixture containing specialized silicon concentrated PV chips the actual solar cells. If you stay by the array for a while, you'll notice that the solar concentrators follow the path of the sun throughout the day, changing position to best capture and utilize the sunlight. The specialized chips that make the technology possible are the brainchild of Bernard Sater, an engineer who had worked at Glenn since the early 1960s before retiring to pursue his unique ideas for harnessing solar power. Sater contributed to multiple PV projects in the latter part of his career at the Center, including research and development on the International Space Station s solar arrays. In his spare time, he enjoyed tinkering with new approaches to solar power, experiments that resulted in the system installed at Glenn today. Sater s basic idea had two components. First, he wanted to create a silicon cell that was smaller, more efficient, and much lower cost than those available at the time. To ensure that the potential of such a chip could be realized, he also planned on pairing it with a system that could concentrate sunlight and focus it directly on the cell. When he retired from Glenn in 1994 to focus on researching and developing the technology full time, Sater found that NASA was interested in the concept and ready to provide funding, facilities, and expertise in order to assist in its development.

  18. PowerFilm PowerShade Fixed Site Solar System Cost Reduction Plan

    Science.gov (United States)

    2014-07-31

    design drawing for the Gen II PowerShade. high. The 27" width was quite acceptable for packing in a diaper and crate. Based on these resuks, we pursued...were cost effectiveness of fabric and solar module utilization . This is essentially choosing dimensions which create minimum scrap material in the...power from a local utility company. Mode 3 is a grid tie connection without external battery storage, in this mode, all the available power from

  19. Power generation from wind turbines in a solar chimney

    Energy Technology Data Exchange (ETDEWEB)

    Foote, Tudor [Graduate Student, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States); Agarwal, Ramesh K. [William Palm Professor, Department of Mechanical Engineering and Materials Science, Washington University in St. Louis, Jolley Hall, Campus Box 1185, One Brookings Drive, St. Louis, Missouri, 63130 (United States)

    2013-07-01

    Recent studies have shown that shrouded wind turbines can generate greater power compared to bare turbines. A solar chimney generates an upward draft of wind inside a tower and a shroud around the wind turbine. There are numerous empty silos on farms in the U.S. that can be converted to solar chimneys with minor modifications at modest cost. The objective of this study is to determine the potential of these silos/chimneys for generating wind power. The study is conducted through analytical/computational approach by employing the commercial Computational Fluid Dynamics (CFD) software. Computations are performed for five different geometric configurations consisting of a turbine, a cylindrical silo, and/or a venturi and/or a diffuser using the dimensions of typical silos and assuming Class 3 wind velocity. The incompressible Navier-Stokes equations with the Boussinesq approximation and a two equation realizable {kappa}-{epsilon} model are employed in the calculations, and the turbine is modeled as an actuator disk. The power coefficient (Cp) and generated power are calculated for the five cases. Consistent with recent literature, it was found that the silos with diffusers increase the Cp beyond Betz’s limit significantly and thus the generated power. It should be noted that Cp is calculated by normalizing it by the turbine area swept by the wind. This study shows the potential of using abandoned silos in the mid-west and other parts of the country for localized wind power generation.

  20. Solar-Powered Plasmon-Enhanced Heterogeneous Catalysis

    Directory of Open Access Journals (Sweden)

    Naldoni Alberto

    2016-06-01

    Full Text Available Photocatalysis uses semiconductors to convert sunlight into chemical energy. Recent reports have shown that plasmonic nanostructures can be used to extend semiconductor light absorption or to drive direct photocatalysis with visible light at their surface. In this review, we discuss the fundamental decay pathway of localized surface plasmons in the context of driving solar-powered chemical reactions. We also review different nanophotonic approaches demonstrated for increasing solar-to-hydrogen conversion in photoelectrochemical water splitting, including experimental observations of enhanced reaction selectivity for reactions occurring at the metalsemiconductor interface. The enhanced reaction selectivity is highly dependent on the morphology, electronic properties, and spatial arrangement of composite nanostructures and their elements. In addition, we report on the particular features of photocatalytic reactions evolving at plasmonic metal surfaces and discuss the possibility of manipulating the reaction selectivity through the activation of targeted molecular bonds. Finally, using solar-to-hydrogen conversion techniques as an example, we quantify the efficacy metrics achievable in plasmon-driven photoelectrochemical systems and highlight some of the new directions that could lead to the practical implementation of solar-powered plasmon-based catalytic devices.

  1. Exergetic analysis of parabolic trough solar thermal power plants

    Science.gov (United States)

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

    2014-12-01

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

  2. Concentrating Solar Power: Best Practices Handbook for the Collection and Use of Solar Resource Data (CSP)

    Energy Technology Data Exchange (ETDEWEB)

    Stoffel, T.; Renne, D.; Myers, D.; Wilcox, S.; Sengupta, M.; George, R.; Turchi, C.

    2010-09-01

    As the world looks for low-carbon sources of energy, solar power stands out as the most abundant energy resource. Harnessing this energy is the challenge for this century. Photovoltaics and concentrating solar power (CSP) are two primary forms of electricity generation using sunlight. These use different technologies, collect different fractions of the solar resource, and have different siting and production capabilities. Although PV systems are most often deployed as distributed generation sources, CSP systems favor large, centrally located systems. Accordingly, large CSP systems require a substantial investment, sometimes exceeding $1 billion in construction costs. Before such a project is undertaken, the best possible information about the quality and reliability of the fuel source must be made available. That is, project developers need to have reliable data about the solar resource available at specific locations to predict the daily and annual performance of a proposed CSP plant. Without these data, no financial analysis is possible. This handbook presents detailed information about solar resource data and the resulting data products needed for each stage of the project.

  3. Flat plate solar collector for water pre-heating using concentrated solar power (CSP)

    Science.gov (United States)

    Peris, Leonard Sunny; Shekh, Md. Al Amin; Sarker, Imran

    2017-12-01

    Numerous attempt and experimental conduction on different methods to harness energy from renewable sources are being conducted. This study is a contribution to the purpose of harnessing solar energy as a renewable source by using flat plate solar collector medium to preheat water. Basic theory of solar radiation and heat convection in water (working fluid) has been combined with heat conduction process by using copper tubes and aluminum absorber plate in a closed conduit, covered with a glazed through glass medium. By this experimental conduction, a temperature elevation of 35°C in 10 minutes duration which is of 61.58% efficiency range (maximum) has been achieved. The obtained data and experimental findings are validated with the theoretical formulation and an experimental demonstration model. A cost effective and simple form of heat energy extraction method for space heating/power generation has been thoroughly discussed with possible industrial implementation possibilities. Under-developed and developing countries can take this work as an illustration for renewable energy utilization for sustainable energy prospect. Also a full structure based data to derive concentrated solar energy in any geographical location of Bangladesh has been outlined in this study. These research findings can contribute to a large extent for setting up any solar based power plant in Bangladesh irrespective of its installation type.

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

    Directory of Open Access Journals (Sweden)

    T. T. Chow

    2012-01-01

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

  5. Anisotropic Behaviour of Magnetic Power Spectra in Solar Wind Turbulence.

    Science.gov (United States)

    Banerjee, S.; Saur, J.; Gerick, F.; von Papen, M.

    2017-12-01

    Introduction:High altitude fast solar wind turbulence (SWT) shows different spectral properties as a function of the angle between the flow direction and the scale dependent mean magnetic field (Horbury et al., PRL, 2008). The average magnetic power contained in the near perpendicular direction (80º-90º) was found to be approximately 5 times larger than the average power in the parallel direction (0º- 10º). In addition, the parallel power spectra was found to give a steeper (-2) power law than the perpendicular power spectral density (PSD) which followed a near Kolmogorov slope (-5/3). Similar anisotropic behaviour has also been observed (Chen et al., MNRAS, 2011) for slow solar wind (SSW), but using a different method exploiting multi-spacecraft data of Cluster. Purpose:In the current study, using Ulysses data, we investigate (i) the anisotropic behaviour of near ecliptic slow solar wind using the same methodology (described below) as that of Horbury et al. (2008) and (ii) the dependence of the anisotropic behaviour of SWT as a function of the heliospheric latitude.Method:We apply the wavelet method to calculate the turbulent power spectra of the magnetic field fluctuations parallel and perpendicular to the local mean magnetic field (LMF). According to Horbury et al., LMF for a given scale (or size) is obtained using an envelope of the envelope of that size. Results:(i) SSW intervals always show near -5/3 perpendicular spectra. Unlike the fast solar wind (FSW) intervals, for SSW, we often find intervals where power parallel to the mean field is not observed. For a few intervals with sufficient power in parallel direction, slow wind turbulence also exhibit -2 parallel spectra similar to FSW.(ii) The behaviours of parallel and perpendicular power spectra are found to be independent of the heliospheric latitude. Conclusion:In the current study we do not find significant influence of the heliospheric latitude on the spectral slopes of parallel and perpendicular

  6. Changes in the chemical composition of the atmosphere in the polar regions of the Earth after solar proton flares (3d modeling)

    Science.gov (United States)

    Krivolutsky, A. A.; Vyushkova, T. Yu.; Mironova, I. A.

    2017-03-01

    The paper presents the results of numerical photochemical simulations of the impact of the most powerful solar proton flares during the 23rd solar cycle on the ozonosphere in the polar regions of the Earth. A global 3D photochemical model, CHARM, developed at Central Aerological Observatory (CAO) was used in the simulations. The model introduces an additional source of nitrogen atoms and OH radicals. These components are formed due to the ionization effect of solar protons in the Earth's atmosphere. The ionization rate was determined from data on proton fluxes measured by GOES satellites. The production rate of additional NO x and HO x molecules per ion pair was based on published theoretical studies. It is shown that the most intense flares in the 23rd solar cycle (2000, 2001, and 2003) destroyed ozone in the mesosphere to a great extent (sometimes completely, for example, during the July 14, 2000, event). It is found that the response of ozone to solar proton events follows a seasonal pattern. For the first time, the long-term effect of solar proton events is identified; it is approximately one year.

  7. Sizing and preliminary hardware testing of solar powered UAV

    Directory of Open Access Journals (Sweden)

    S. Jashnani

    2013-12-01

    Full Text Available Integrating solar energy into modern aircraft technology has been a topic of interest and has received a lot of attention from researchers over the last two decades. A few among the many potential applications of this technology are the possibility of continuous self sustained flight for purposes such as information relay, surveillance and monitoring. This paper discusses the altitude and payload mass, as independent parameters, and their influence on the size and design of the aircraft. To estimate available solar power, two different models have been presented; one for low altitudes and the other for high altitudes. An engineering ground model was built to simulate the power and propulsion system over 24 h of continuous operation. The paper presents data from tests performed till date and lessons learnt while dealing with the construction of the engineering ground model as well as changes that can be made to improve the design.

  8. Starting characteristics of direct current motors powered by solar cells

    Science.gov (United States)

    Singer, S.; Appelbaum, J.

    1989-01-01

    Direct current motors are used in photovoltaic systems. Important characteristics of electric motors are the starting to rated current and torque ratios. These ratios are dictated by the size of the solar cell array and are different for the various dc motor types. Discussed here is the calculation of the starting to rated current ratio and starting to rated torque ratio of the permanent magnet, and series and shunt excited motors when powered by solar cells for two cases: with and without a maximum-power-point-tracker (MPPT) included in the system. Comparing these two cases, one gets a torque magnification of about 3 for the permanent magnet motor and about 7 for other motor types. The calculation of the torques may assist the PV system designer to determine whether or not to include an MPPT in the system.

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

    Science.gov (United States)

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

    1985-01-01

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

  10. Power spectra of mesospheric velocities in polar regions

    Science.gov (United States)

    Czechowsky, P.; Ruster, R.

    1985-01-01

    The mobile SOUSY radar was operated on Andoya in Northern Norway during the MAP/WINE campaign from November 1983 to February 1984 and for about two weeks in June 1984 to study the seasonal dependence of mesospheric structures and dynamics at polar latitudes. During the winter period, measurements were carried out on 57 days, primarily in coordination with the schedule of the rocket experiments. Echoes were detected in the troposphere and stratosphere up to 30 km and at mesospheric heights from about 50 to 90 km with a distinct maximum around noon. In summer, the radar system was operated continuously from 19th to the 28th of June 1984. Echoes occurred almost for 24 hours in the height range from 70 to 95 km showing no recognizable diurnal variation. Similar observations in polar latitudes were carried out for several years with the Poker Flat Radar in Alaska.

  11. 24/7 Solar Minimum Polar Cap and Auroral Ion Temperature Observations

    Science.gov (United States)

    Sojka, Jan J.; Nicolls, Michael; van Eyken, Anthony; Heinselman, Craig; Bilitza, Dieter

    2011-01-01

    During the International Polar Year (IPY) two Incoherent Scatter Radars (ISRs) achieved close to 24/7 continuous observations. This presentation describes their data sets and specifically how they can provide the International Reference Ionosphere (IRI) a fiduciary E- and F-region ionosphere description for solar minimum conditions in both the auroral and polar cap regions. The ionospheric description being electron density, ion temperature and electron temperature profiles from as low as 90 km extending to several scale heights above the F-layer peak. The auroral location is Poker Flat in Alaska at 65.1 N latitude, 212.5 E longitude where the NSF s new Poker Flat Incoherent Scatter Radar (PFISR) is located. This location during solar minimum conditions is in the auroral region for most of the day but is at midlatitudes, equator ward of the cusp, for about 4-8 h per day dependent upon geomagnetic activity. In contrast the polar location is Svalbard, at 78.2 N latitude, 16.0 E longitude where the EISCAT Svalbard Radar (ESR) is located. For most of the day the ESR is in the Northern Polar Cap with a noon sector passage often through the dayside cusp. Of unique relevance to IRI is that these extended observations have enabled the ionospheric morphology to be distinguished between quiet and disturbed geomagnetic conditions. During the IPY year, 1 March 2007 - 29 February 2008, about 50 solar wind Corotating Interaction Regions (CIRs) impacted geospace. Each CIR has a two to five day geomagnetic disturbance that is observed in the ESR and PFISR observations. Hence, this data set also enables the quiet-background ionospheric climatology to be established as a function of season and local time. These two separate climatologies for the ion temperature at an altitude of 300 km are presented and compared with IRI ion temperatures. The IRI ion temperatures are about 200-300 K hotter than the observed values. However, the MSIS neutral temperature at 300 km compares favorably

  12. Solar Electricity: The Power of Choice, Third Quarter 2001

    Energy Technology Data Exchange (ETDEWEB)

    Schnelten, K.; Moon, S.; Miller, J.

    2001-12-01

    Solar Electricity: The Power of Choice (formerly NREL PV Working With Industry) is a quarterly newsletter devoted to the photovoltaics (PV) research and development activities performed by NREL staff in concert with their industry and university partners. This issue is devoted to coverage of the Program Review Meeting of the National Center for Photovoltaics, held in October, 2001. The editorialist for this issue is Kannan Ramanathan, chair of the Program Review and a research scientist with the National Center for Photovoltaics at NREL.

  13. Solar powered irrigation management using neutron scattering technique

    International Nuclear Information System (INIS)

    Hegazi, A.M.A

    2010-01-01

    This study was conducted to modify a locally assembled solar-powered irrigation system. A direct-coupled photovoltaic pumping system has been assembled and installed in the Egyptian desert in Inshas at the Nuclear Research Center (31 degree 21 ' E, 30 degree 17 ' N). 800 Watt DC motor with brushes was modified to match unsteady PV generator current output. The DC motor was supplied with PV generator current, which was divided between 9 and 4 modules. Pump-set output was tested at different insolation levels and a relationship was carried out from observed data. Hourly solar insolation averages for ten years period were obtained from a program named (Meteo-Norm) software in order to predict and calculate the average daily pumping system water delivery in cubic meters. Preliminary experiment was conducted to acquire a relationship between PVP system outputs and solar-radiation intensity values; which differ from time to time during the day and through different seasons. Solar radiation, power consumption (as Voltage and Current), motor RPM and pump flow varied, while head was kept constant at 4 meter.The system showed trustworthy response to the PV generator output power demonstrated in DC motor RPM and consequently water deliver Based on the obtained results of this study, conclusions are:1.Parameters affecting the performance of solar generator under desert conditions were ambient temperature and contaminants. Focusing on the controllable parameter; dust contaminants; experiments were made to find out the best cleaning period which has limited decrease of the PV output. Results showed that output power was 22% lower for the panel with no cleaning for 20 days. Recommendation is made to do cleaning schedule every three days. 2.Maximizing photovoltaic system efficiency is achieved in order to minimize the initial costs, in other words; more power generated from the PV system unit. These can be obtained by tracking the sun rays through the daytime. Solar tracker was

  14. Electrostatic protection of the solar power satellite and rectenna. Part 1: Protection of the solar power satellite

    Science.gov (United States)

    1980-01-01

    Several features of the interactions of the Solar Power Satellite (SPS) with its space environment are examined theoretically. The voltages produced at various surfaces due to space plasmas and the plasma leakage currents through the kapton and sapphire solar cell blankets are calculated. At geosynchronous orbit, this parasitic power loss is only 0.7%, and is easily compensated by oversizing. At low Earth orbit, the power loss is potentially much larger (3%), and anomalous arcing is expected for the EOTV high voltage negative surfaces. Preliminary results of a three dimensional self consistent plasma and electric field computer program are presented, confirming the validity of the predictions made from the one dimensional models. Lastly, magnetic shielding of the satellite is considered to reduce the power drain and to protect the solar cells from energetic electron and plasma ion bombardment. It is concluded that minor modifications can allow the SPS to operate safely and efficiently in its space environment. Subsequent design changes will substantially alter the basic conclusions.

  15. concentrated solar power and solar thermal Barometer - EurObserv'ER - May 2015

    International Nuclear Information System (INIS)

    2015-05-01

    European concentrated solar power capacity remained stable in 2014 and will probably post a negligible increase in 2015. Construction work on a number of new facilities in Italy that are scheduled for commissioning in 2016 and 2017 could commence in the second half of the year. The European solar thermal market for producing heat, domestic hot water and heating has not found the recipe for recovery. According to EurObserv'ER, the market contracted by a further 3.7% from its 2013 level which is the sixth decrease in a row

  16. Non-Power Purchase Agreement (PPA) Options for Financing Solar Deployment at Universities

    Energy Technology Data Exchange (ETDEWEB)

    2016-10-01

    Financing solar using power purchase agreements (PPAs) has facilitated solar deployment of more than 100 megawatts (MW) at universities--as compared to 50 MW facilitated by financing models not using PPAs. This brochure, which overviews existing financing models and funding mechanisms available for solar procurement, focuses on non-PPA financing models. For more information on solar deployment at universities using PPAs, refer to Using Power Purchase Agreements for Solar Deployment at Universities.

  17. Assessment of distributed solar power systems: Issues and impacts

    Science.gov (United States)

    Moyle, R. A.; Chernoff, H.; Schweizer, T. C.; Patton, J. B.

    1982-11-01

    The installation of distributed solar-power systems presents electric utilities with a host of questions. Some of the technical and economic impacts of these systems are discussed. Among the technical interconnect issues are isolated operation, power quality, line safety, and metering options. Economic issues include user purchase criteria, structures and installation costs, marketing and product distribution costs, and interconnect costs. An interactive computer program that allows easy calculation of allowable system prices and allowable generation-equipment prices was developed as part of this project. It is concluded that the technical problems raised by distributed solar systems are surmountable, but their resolution may be costly. The stringent purchase criteria likely to be imposed by many potential system users and the economies of large-scale systems make small systems (less than 10 to 20 kW) less attractive than larger systems. Utilities that consider life-cycle costs in making investment decisions and third-party investors who have tax and financial advantages are likely to place the highest value on solar-power systems.

  18. Solar updraft power generator with radial and curved vanes

    Science.gov (United States)

    Hafizh, Hadyan; Hamsan, Raziff; Zamri, Aidil Azlan Ahmad; Keprawi, Mohamad Fairuz Mohamad; Shirato, Hiromichi

    2018-02-01

    Solar radiation is the largest source of energy available on earth and the solar updraft power generator (SUPG) is a renewable energy facility capable of harnessing its abundant power. Unlike the conventional wind turbines that harness natural wind in the atmosphere and often encounter with the intermittent issue or even complete cut-off from airflow, the SUPG creates artificial wind as a result of solar-induced convective flows. However, the SUPG has an inherent low total efficiency due to the conversion of thermal energy into pressure energy. Acknowledging the low efficiency and considering its potential as a renewable energy facility, the current work aims to increase the total efficiency by installing a series of guide walls inside the collector. Two types of guide walls were used i.e. radial and curved vanes. The result with curved vanes showed that the updraft velocity is higher compare to those without vanes. About 18% and 64% improvement of updraft velocity and mechanical power were attained respectively. Furthermore, it was observed that the role of radial vanes configuration was more to produce a smooth updraft velocity profile rather than increasing the total efficiency.

  19. More on duel purpose solar-electric power plants

    Science.gov (United States)

    Hall, F. F.

    Rationale for such plants is reviewed and plant elements are listed. Dual purpose solar-electric plants would generate both electricity and hydrogen gas for conversion to ammonia or methanol or direct use as a fuel of unsurpassed specific power and cleanliness. By-product oxygen would also be sold to owners of hydrogen age equipment. Evolved gasses at high pressure could be fired in compressorless gas turbines, boilerless steam-turbines or fuel-cell-inverter hydrogen-electric power drives of high thermal efficiency as well as in conventional internal combustion engines.

  20. Solar Powering Your Community: A Guide for Local Governments; Second Edition

    Energy Technology Data Exchange (ETDEWEB)

    2011-01-01

    DOE designed this guide "Solar Powering Your Community: A Guide for Local Governments" to assist local government officials and stakeholders in designing and implementing strategic local solar plans. The 2011 edition contains the most recent lessons and successes from the 25 Solar America Cities and other communities promoting solar energy. Because DOE recognizes that there is no one path to solar market development, this guide introduces a range of policy and program options that can help a community build a local solar infrastructure.

  1. Mortality monitoring design for utility-scale solar power facilities

    Science.gov (United States)

    Huso, Manuela; Dietsch, Thomas; Nicolai, Chris

    2016-05-27

    IntroductionSolar power represents an important and rapidly expanding component of the renewable energy portfolio of the United States (Lovich and Ennen, 2011; Hernandez and others, 2014). Understanding the impacts of renewable energy development on wildlife is a priority for the U.S. Fish and Wildlife Service (FWS) in compliance with Department of Interior Order No. 3285 (U.S. Department of the Interior, 2009) to “develop best management practices for renewable energy and transmission projects on the public lands to ensure the most environmentally responsible development and delivery of renewable energy.” Recent studies examining effects of renewable energy development on mortality of migratory birds have primarily focused on wind energy (California Energy Commission and California Department of Fish and Game, 2007), and in 2012 the FWS published guidance for addressing wildlife conservation concerns at all stages of land-based wind energy development (U.S. Fish and Wildlife Service, 2012). As yet, no similar guidelines exist for solar development, and no published studies have directly addressed the methodology needed to accurately estimate mortality of birds and bats at solar facilities. In the absence of such guidelines, ad hoc methodologies applied to solar energy projects may lead to estimates of wildlife mortality rates that are insufficiently accurate and precise to meaningfully inform conversations regarding unintended consequences of this energy source and management decisions to mitigate impacts. Although significant advances in monitoring protocols for wind facilities have been made in recent years, there remains a need to provide consistent guidance and study design to quantify mortality of bats, and resident and migrating birds at solar power facilities (Walston and others, 2015).In this document, we suggest methods for mortality monitoring at solar facilities that are based on current methods used at wind power facilities but adapted for the

  2. The Solar Umbrella: A Low-cost Demonstration of Scalable Space Based Solar Power

    Science.gov (United States)

    Contreras, Michael T.; Trease, Brian P.; Sherwood, Brent

    2013-01-01

    Within the past decade, the Space Solar Power (SSP) community has seen an influx of stakeholders willing to entertain the SSP prospect of potentially boundless, base-load solar energy. Interested parties affiliated with the Department of Defense (DoD), the private sector, and various international entities have all agreed that while the benefits of SSP are tremendous and potentially profitable, the risk associated with developing an efficient end to end SSP harvesting system is still very high. In an effort to reduce the implementation risk for future SSP architectures, this study proposes a system level design that is both low-cost and seeks to demonstrate the furthest transmission of wireless power to date. The overall concept is presented and each subsystem is explained in detail with best estimates of current implementable technologies. Basic cost models were constructed based on input from JPL subject matter experts and assume that the technology demonstration would be carried out by a federally funded entity. The main thrust of the architecture is to demonstrate that a usable amount of solar power can be safely and reliably transmitted from space to the Earth's surface; however, maximum power scalability limits and their cost implications are discussed.

  3. Power Management Strategy by Enhancing the Mission Profile Configuration of Solar-Powered Aircraft

    Directory of Open Access Journals (Sweden)

    Parvathy Rajendran

    2016-01-01

    Full Text Available Solar energy offers solar-powered unmanned aerial vehicle (UAV the possibility of unlimited endurance. Some researchers have developed techniques to achieve perpetual flight by maximizing the power from the sun and by flying in accordance with its azimuth angles. However, flying in a path that follows the sun consumes more energy to sustain level flight. This study optimizes the overall power ratio by adopting the mission profile configuration of optimal solar energy exploitation. Extensive simulation is conducted to optimize and restructure the mission profile phases of UAV and to determine the optimal phase definition of the start, ascent, and descent periods, thereby maximizing the energy from the sun. In addition, a vertical cylindrical flight trajectory instead of maximizing the solar inclination angle has been adopted. This approach improves the net power ratio by 30.84% compared with other techniques. As a result, the battery weight may be massively reduced by 75.23%. In conclusion, the proposed mission profile configuration with the optimal power ratio of the trajectory of the path planning effectively prolongs UAV operation.

  4. 100 Gbps IM/DD links using quad-polarization: Performance, complexity, and power dissipation

    DEFF Research Database (Denmark)

    Saldaña Cercos, Silvia; Piels, Molly; Estaran Tolosa, Jose Manuel

    2015-01-01

    A computational complexity, power consumption, and receiver sensitivity analysis for three different scenarios for short-range direct detection links is presented: 1) quad-polarization, 2) wavelength division multiplexing (WDM), and 3) parallel optics. Results show that the power consumption...... penalty associated to the quad-polarization digital signal processing (DSP) is negligibly small. However, the required analog to digital converters account for 47.6% of the total system power consumption. Transmission of 4x32 Gbps over 2 km standard single mode fiber is achieved with a receiver...

  5. Design of a nanopatterned long focal-length planar focusing collector for concentrated solar power

    Science.gov (United States)

    Ding, Qing; Choubal, Aakash; Toussaint, Kimani C.

    2017-02-01

    Concentrated solar power (CSP) facilities heavily utilize parabolic troughs to collect and concentrate sunlight onto receivers that deliver solar thermal energy to heat engines for generating electricity. However, parabolic troughs are bulky and heavy and result in a large capital investment for CSP plants, thereby making it difficult for CSP technology to be competitive with photovoltaics. We present the design of a planar focusing collector (PFC) with focal length beyond the micron scale. The PFC design is based on the use of a nanostructured silver surface for linearly polarized singlewavelength light. The designed PFC consists of metallic nanogrooves on a dielectric substrate. The geometric properties, namely the width and depth, of a single-unit nanogroove allows for full control of the optical phase at desired spatial coordinates along the nanogroove short-axis for a single wavelength. Moreover, we show numerically that such phase control can be used to construct a phase front that mimics that of a cylindrical lens. In addition, we determine the concentration ratio by comparing the width of our PFC design to the cross-sectional width of its focal spot. We also determine the conversion efficiency at long focal lengths by evaluating the ratio of the collected optical power to the incoming optical power. Finally, we examine the focusing behavior across multiple wavelengths and angles of incidence. Our work shows how nano-optics and plasmonics could contribute to this important area of CSP technology.

  6. Onset of the Magnetic Explosion in Solar Polar Coronal X-Ray Jets

    Science.gov (United States)

    Moore, Ronald L.; Sterling, Alphonse C.; Panesar, Navdeep

    2017-08-01

    We examine the onset of the driving magnetic explosion in 15 random polar coronal X-ray jets. Each eruption is observed in a coronal X-ray movie from Hinode and in a coronal EUV movie from Solar Dynamics Observatory. Contrary to the Sterling et al (2015, Nature, 523, 437) scenario for minifilament eruptions that drive polar coronal jets, these observations indicate: (1) in most polar coronal jets (a) the runaway internal tether-cutting reconnection under the erupting minifilament flux rope starts after the spire-producing breakout reconnection starts, not before it, and (b) aleady at eruption onset, there is a current sheet between the explosive closed magnetic field and ambient open field; and (2) the minifilament-eruption magnetic explosion often starts with the breakout reconnection of the outside of the magnetic arcade that carries the minifilament in its core. On the other hand, the diversity of the observed sequences of occurrence of events in the jet eruptions gives further credence to the Sterlling et al (2015, Nature, 523, 437) idea that the magnetic explosions that make a polar X-ray jet work the same way as the much larger magnetic explosions that make and flare and CME. We point out that this idea, and recent observations indicating that magnetic flux cancelation is the fundamental process that builds the field in and around pre-jet minifilaments and triggers the jet-driving magnetic explosion, together imply that usually flux cancelation inside the arcade that explodes in a flare/CME eruption is the fundamental process that builds the explosive field and triggers the explosion.This work was funded by the Heliophysics Division of NASA's Science Mission Directorate through its Living With a Star Targeted Research and Technology Program, its Heliophsyics Guest Investigators Program, and the Hinode Project.

  7. Utilizing Maximum Power Point Trackers in Parallel to Maximize the Power Output of a Solar (Photovoltaic) Array

    Science.gov (United States)

    2012-12-01

    input and output parameters required for efficiency calculations. 70 B. MPPT SELECTION 1. STEVAL SPV1020 MPPT with DC-DC Boost Converter The...the power output of the solar array. Currently, most military applications that utilize solar energy omit or use only a single MPPT per PV system. The...photovoltaic (PV) system to use a maximum power point tracker ( MPPT ) to increase the power output of the solar array. Currently, most military

  8. Modeling of Maximum Power Point Tracking Controller for Solar Power System

    Directory of Open Access Journals (Sweden)

    Aryuanto Soetedjo

    2012-09-01

    Full Text Available In this paper, a Maximum Power Point Tracking (MPPT controller for solar power system is modeled using MATLAB Simulink. The model consists of PV module, buck converter, and MPPT controller. The contribution of the work is in the modeling of buck converter that allowing the input voltage of the converter, i.e. output voltage of PV is changed by varying the duty cycle, so that the maximum power point could be tracked when the environmental changes. The simulation results show that the developed model performs well in tracking the maximum power point (MPP of the PV module using Perturb and Observe (P&O Algorithm.

  9. Development of solar concentrators for high-power solar-pumped lasers.

    Science.gov (United States)

    Dinh, T H; Ohkubo, T; Yabe, T

    2014-04-20

    We have developed unique solar concentrators for solar-pumped solid-state lasers to improve both efficiency and laser output power. Natural sunlight is collected by a primary concentrator which is a 2  m×2  m Fresnel lens, and confined by a cone-shaped hybrid concentrator. Such solar power is coupled to a laser rod by a cylinder with coolant surrounding it that is called a liquid light-guide lens (LLGL). Performance of the cylindrical LLGL has been characterized analytically and experimentally. Since a 14 mm diameter LLGL generates efficient and uniform pumping along a Nd:YAG rod that is 6 mm in diameter and 100 mm in length, 120 W cw laser output is achieved with beam quality factor M2 of 137 and overall slope efficiency of 4.3%. The collection efficiency is 30.0  W/m2, which is 1.5 times larger than the previous record. The overall conversion efficiency is more than 3.2%, which can be comparable to a commercial lamp-pumped solid-state laser. The concept of the light-guide lens can be applied for concentrator photovoltaics or other solar energy optics.

  10. Scope for solar hydrogen power plants along Indian coasts

    Science.gov (United States)

    Hajra, Debdyut; Mukhopadhyay, Swarnav

    2016-09-01

    Energy is at the core of economic growth and development in the present day world. But relentless and unchecked use of harmful energy resources like fossil fuels (coil and oil), nuclear energy has taken a toll on mother nature. The energy coffers are being rapidly depleted and within a few years all of them will become empty, leaving nothing for the future generations to build on. Their constant usage has degraded the air quality and given way to land and water pollution. Scientists and world leaders have initiated a call for action to shift our dependence from currently popular energy sources to cleaner and renewable energy sources. Search for such energy sources have been going on for many years. Solar energy, wind energy, ocean energy, tidal energy, biofuel, etc. have caught the attention of people. Another such important which has become popular is 'Solar Hydrogen'. Many visionary scientists have called hydrogen the energy of the future. It is produced from water by direct or indirect use of sunlight in a sustainable manner. This paper discusses the current energy scenario, the importance of solar-hydrogen as a fuel and most importantly the scope for solar hydrogen power plants along Indian coastline.

  11. Dynamic Modeling of the Solar Field in Parabolic Trough Solar Power Plants

    Directory of Open Access Journals (Sweden)

    Lourdes A. Barcia

    2015-11-01

    Full Text Available Parabolic trough solar power plants use a thermal fluid to transfer thermal energy from solar radiation to a water-steam Rankine cycle in order to drive a turbine that, coupled to an electrical generator, produces electricity. These plants have a heat transfer fluid (HTF system with the necessary elements to transform solar radiation into heat and to transfer that thermal energy to the water-steam exchangers. In order to get the best possible performance in the Rankine cycle and, hence, in the thermal plant, it is necessary that the thermal fluid reach its maximum temperature when leaving the solar field (SF. Also, it is mandatory that the thermal fluid does not exceed the maximum operating temperature of the HTF, above which it degrades. It must be noted that the optimal temperature of the thermal fluid is difficult to obtain, since solar radiation can change abruptly from one moment to another. The aim of this document is to provide a model of an HTF system that can be used to optimize the control of the temperature of the fluid without interfering with the normal operation of the plant. The results obtained with this model will be contrasted with those obtained in a real plant.

  12. Solar Electric Propulsion (SEP) Tug Power System Considerations

    Science.gov (United States)

    Kerslake, Thomas W.; Bury, Kristen M.; Hojinicki, Jeffrey S.; Sajdak, Adam M.; Scheiddegger, Robert J.

    2011-01-01

    Solar electric propulsion (SEP) technology is truly at the "intersection of commercial and military space" as well as the intersection of NASA robotic and human space missions. Building on the use of SEP for geosynchronous spacecraft station keeping, there are numerous potential commercial and military mission applications for SEP stages operating in Earth orbit. At NASA, there is a resurgence of interest in robotic SEP missions for Earth orbit raising applications, 1-AU class heliocentric missions to near Earth objects (NEOs) and SEP spacecraft technology demonstrations. Beyond these nearer term robotic missions, potential future human space flight missions to NEOs with high-power SEP stages are being considered. To enhance or enable this broad class of commercial, military and NASA missions, advancements in the power level and performance of SEP technologies are needed. This presentation will focus on design considerations for the solar photovoltaic array (PVA) and electric power system (EPS) vital to the design and operation of an SEP stage. The engineering and programmatic pros and cons of various PVA and EPS technologies and architectures will be discussed in the context of operating voltage and power levels. The impacts of PVA and EPS design options on the remaining SEP stage subsystem designs, as well as spacecraft operations, will also be discussed.

  13. Study on Pyroelectric Harvesters Integrating Solar Radiation with Wind Power

    Directory of Open Access Journals (Sweden)

    Chun-Ching Hsiao

    2015-07-01

    Full Text Available Pyroelectric harvesters use temperature fluctuations to generate electrical outputs. Solar radiation and waste heat are rich energy sources that can be harvested. Pyroelectric energy converters offer a novel and direct energy-conversion technology by transforming time-dependent temperatures directly into electricity. Moreover, the great challenge for pyroelectric energy harvesting lies in finding promising temperature variations or an alternating thermal loading in real situations. Hence, in this article, a novel pyroelectric harvester integrating solar radiation with wind power by the pyroelectric effect is proposed. Solar radiation is a thermal source, and wind is a dynamic potential. A disk generator is used for harvesting wind power. A mechanism is considered to convert the rotary energy of the disk generator to drive a shutter for generating temperature variations in pyroelectric cells using a planetary gear system. The optimal period of the pyroelectric cells is 35 s to harvest the stored energy, about 70 μJ, while the rotary velocity of the disk generator is about 31 RPM and the wind speed is about 1 m/s. In this state, the stored energy acquired from the pyroelectric harvester is about 75% more than that from the disk generator. Although the generated energy of the proposed pyroelectric harvester is less than that of the disk generator, the pyroelectric harvester plays a complementary role when the disk generator is inactive in situations of low wind speed.

  14. The potential of concentrating solar power in South Africa

    Energy Technology Data Exchange (ETDEWEB)

    Fluri, Thomas P. [Department of Mechanical and Mechatronic Engineering, University of Stellenbosch, Private Bag X1, Matieland 7602 (South Africa)

    2009-12-15

    In this paper all provinces of South Africa with a good potential for the implementation of large-scale concentrating solar power plants are identified using geographic information systems. The areas are assumed suitable if they get sufficient sunshine, are close enough to transmission lines, are flat enough, their respective vegetation is not under threat and they have a suitable land use profile. Various maps are created showing the solar resource, the slope, areas with 'least threatened' vegetation, proximity to transmission lines and areas suitable for the installation of large concentrating solar power plants. Assuming the installation of parabolic trough plants, it is found that the identified suitable areas could accommodate plants with a nominal capacity of 510.3 GW in the Northern Cape, 25.3 GW in the Free State, 10.5 GW in the Western Cape and 1.6 GW in the Eastern Cape, which gives a total potential nominal capacity of 547.6 GW for the whole country. (author)

  15. The performance of the first Jordan Badia's solar powered refrigerator

    International Nuclear Information System (INIS)

    Mohammed Awwad Al-Dabbas

    2012-01-01

    We are facing a significant challenge in Jordan's Badia region. Such challenge present us given that it will be environmentally protected with easy access to the refrigeration process to food and medical vaccines keeping at a reasonably and economical low cost. Solar cooling method that is generated from the sun as a substitute for batteries or electrical power is characteristic of its kind to store a power system for continued use. A pilot project of solar refrigerator was tested to collect technological data on a standard basis so the method control tests are accurate and precise. Solar refrigerator does not require electricity, which utilizes a combination of heat conduction and convection. In addition, it can be made from readily available material such as cardboard, sand, and recycled metal. It is constructed from two cylinders: an inner metal cylinder, fitted inside, and an outer cylinder that can be made of wood or plastic, etc, and organic material such as (sand, wool, or soil) placed in the left space between the two cylinders which is then saturated with water. As heat from the sun evaporates the water, the inner chamber is cooled to reduce and maintains the temperature at (6 degree C). (authors)

  16. Radiation Testing of PICA at the Solar Power Tower

    Science.gov (United States)

    White, Susan

    2010-01-01

    Sandia National Laboratory's Solar Power Tower was used to irradiate specimens of Phenolic Impregnated Carbon Ablator (PICA), in order to evaluate whether this thermal protection system material responded differently to potential shock layer radiative heating than to convective heating. Tests were run at 50, 100 and 150 Watts per square centimeter levels of concentrated solar radiation. Experimental results are presented both from spectral measurements on 1- 10 mm thick specimens of PICA, as well as from in-depth temperature measurements on instrumented thicker test specimens. Both spectral measurements and measured in-depth temperature profiles showed that, although it is a porous, low-density material, PICA does not exhibit problematic transparency to the tested high levels of NIR radiation, for all pragmatic cm-to-inch scale thicknesses. PICA acted as a surface absorber to efficiently absorb the incident visible and near infrared incident radiation in the top 2 millimeter layer in the Solar Power Tower tests up to 150 Watts per square centimeter.

  17. Precipitation and total power consumption in the ionosphere: Global MHD simulation results compared with Polar and SNOE observations

    Directory of Open Access Journals (Sweden)

    M. Palmroth

    2006-05-01

    Full Text Available We compare the ionospheric electron precipitation morphology and power from a global MHD simulation (GUMICS-4 with direct measurements of auroral energy flux during a pair of substorms on 28-29 March 1998. The electron precipitation power is computed directly from global images of auroral light observed by the Polar satellite ultraviolet imager (UVI. Independent of the Polar UVI measurements, the electron precipitation energy is determined from SNOE satellite observations on the thermospheric nitric oxide (NO density. We find that the GUMICS-4 simulation reproduces the spatial variation of the global aurora rather reliably in the sense that the onset of the substorm is shown in GUMICS-4 simulation as enhanced precipitation in the right location at the right time. The total integrated precipitation power in the GUMICS-4 simulation is in quantitative agreement with the observations during quiet times, i.e., before the two substorm intensifications. We find that during active times the GUMICS-4 integrated precipitation is a factor of 5 lower than the observations indicate. However, we also find factor of 2-3 differences in the precipitation power among the three different UVI processing methods tested here. The findings of this paper are used to complete an earlier objective, in which the total ionospheric power deposition in the simulation is forecasted from a mathematical expression, which is a function of solar wind density, velocity and magnetic field. We find that during this event, the correlation coefficient between the outcome of the forecasting expression and the simulation results is 0.83. During the event, the simulation result on the total ionospheric power deposition agrees with observations (correlation coefficient 0.8 and the AE index (0.85.

  18. Feasibility Investigation for a Solar Power Generation Facility

    Science.gov (United States)

    Nathan, Lakshmi

    2010-01-01

    The Energy Policy Act of 2005 states that by fiscal year 2013, at least 7.5% of the energy consumed by the government must be renewable energy. In an effort to help meet this goal, Johnson Space Center (JSC) is considering installing a solar power generation facility. The purpose of this project is to conduct a feasibility investigation for such a facility. Because Kennedy Space Center (KSC) has a solar power generation facility, the first step in this investigation is to learn about KSC's facility and obtain information on how it was constructed. After collecting this information, the following must be determined: the amount of power desired, the size of the facility, potential locations for it, and estimated construction and maintenance costs. Contacts with JSC's energy provider must also be established to determine if a partnership would be agreeable to both parties. Lastly, all of this data must be analyzed to decide whether or not JSC should construct the facility. The results from analyzing the data collected indicate that a 200 kW facility would provide enough energy to meet 1% of JSC's energy demand. This facility would require less than 1 acre of land. In the map below, potential locations are shown in green. The solar power facility is projected to cost $2 M. So far, the information collected indicates that such a facility could be constructed. The next steps in this investigation include contacting JSC's energy provider, CenterPoint Energy, to discuss entering a partnership; developing a life cycle cost analysis to determine payback time; developing more detailed plans; and securing funding.

  19. Lightweight DC-DC Converter with Partial Power Processing and MPPT for a Solar Powered Aircraft

    Science.gov (United States)

    Diab-Marzouk, Ahmad

    A lightweight dc-dc partial power processing converter is demonstrated for solar aerospace applications. A system-level model is conceived to determine conformity to payload and target distance objectives, with the Solarship aircraft used as an application example. The concept of partial power processing is utilized to realize a high efficiency lightweight converter that performs Max Peak Power Tracking (MPPT) to transfer power from the aircraft solar array to the high-voltage battery bus. The isolated Cuk is determined to be a suitable converter topology for the application. A small-signal model is derived for control design. The operation of a 400V, 2.7 kW prototype is verified at high frequency (200 kHz), high efficiency (> 98%), small mass (0.604 kg), and uses no electrolytic capacitors. MPPT operation is verified on a 376 V commercial solar installation at The University of Toronto. The prototype serves as an enabling technology for solar aerospace applications.

  20. Intelligent solar-powered automobile-ventilation system

    International Nuclear Information System (INIS)

    Huang, K. David; Tzeng, S.-C.; Ma Weiping; Wu Mingfung

    2005-01-01

    This study adopts airflow management technology to improve the local temperature distributions in an automobile to counteract the greenhouse effect. The automobile's temperature can be reduced to almost the outside temperature before the driver or passenger gets into the vehicle. When the engine is idling, the greenhouse-control system can be activated to remove the hot air from the car. An appropriate negative pressure is maintained to prevent stuffiness and save energy. The greenhouse-control system requires electrical power when the engine is idle, and a battery cannot supply sufficient power. An auxiliary solar-power supply can save energy and reduce the greenhouse effect of sunlight, while creating a comfortable traveling environment. It ensures that the engine is not overburdened and increases its service life, conserving energy, protecting the environment and improving comfort

  1. Solar Stirling power generation - Systems analysis and preliminary tests

    Science.gov (United States)

    Selcuk, M. K.; Wu, Y.-C.; Moynihan, P. I.; Day, F. D., III

    1977-01-01

    The feasibility of an electric power generation system utilizing a sun-tracking parabolic concentrator and a Stirling engine/linear alternator is being evaluated. Performance predictions and cost analysis of a proposed large distributed system are discussed. Design details and preliminary test results are presented for a 9.5 ft diameter parabolic dish at the Jet Propulsion Laboratory (Caltech) Table Mountain Test Facility. Low temperature calorimetric measurements were conducted to evaluate the concentrator performance, and a helium flow system is being used to test the solar receiver at anticipated working fluid temperatures (up to 650 or 1200 C) to evaluate the receiver thermal performance. The receiver body is designed to adapt to a free-piston Stirling engine which powers a linear alternator assembly for direct electric power generation. During the next phase of the program, experiments with an engine and receiver integrated into the concentrator assembly are planned.

  2. Solar powered rotorcraft: a multidisciplinary engineering challenge for undergraduate students

    Science.gov (United States)

    Danner, Aaron J.; Henz, Martin; Teo, Brian Shohei

    2017-08-01

    Controlled, fully solar-powered flight in a rotorcraft is a difficult engineering challenge. Over the past five years, multidiciplinary teams of undergraduate engineering students at the National University of Singapore have built and test-flown a succession of increasingly impressive and larger, more efficient aircraft. While many other multidisciplinary or purely photonics projects are available to students in our programme, this particular project attracts an unusual level of excitement and devotion among students working on it. Why is that the case, and what, in general, makes a good final year undergraduate design project? These questions will be explored. Additionally, videos of solar helicopter test flights and spectacular crashes will be shown in the presentation for which the proceedings below have been prepared.

  3. Numerical evaluation of the Kalina cycle for concentrating solar power plants

    DEFF Research Database (Denmark)

    Modi, Anish

    Concentrating solar power plants use a number of reflecting mirrors to focus and convert the incident solar energy to heat, and a power cycle to convert this heat into electricity. One of the key challenges currently faced by the solar industry is the high cost of electricity production....... These costs may be driven down by developing more cost-effective plant components and improving the system designs. This thesis focuses on the power cycle aspect of the concentrating solar power plants by studying the use a Kalina cycle with ammonia-water mixtures as the cycle working fluid. The potential...... of using a Kalina cycle is evaluated with a thermoeconomic optimization with a turbine inlet temperature of 500 C for a central receiver solar power plant with direct vapour generation, and 370 C for a parabolic trough solar power plant with Therminol VP-1 as the solar field heat transfer fluid. No thermal...

  4. Early commercial demonstration of space solar power using ultra-lightweight arrays

    Science.gov (United States)

    Reed, Kevin; Willenberg, Harvey J.

    2009-11-01

    Space solar power shows great promise for future energy sources worldwide. Most central power stations operate with power capacity of 1000 MW or greater. Due to launch size limitations and specific power of current, rigid solar arrays, the largest solar arrays that have flown in space are around 50 kW. Thin-film arrays offer the promise of much higher specific power and deployment of array sizes up to several MW with current launch vehicles. An approach to early commercial applications for space solar power to distribute power to charge hand-held, mobile battery systems by wireless power transmission (WPT) from thin-film solar arrays in quasi-stationary orbits will be presented. Four key elements to this prototype will be discussed: (1) Space and near-space testing of prototype wireless power transmission by laser and microwave components including WPT space to space and WPT space to near-space HAA transmission demonstrations; (2) distributed power source for recharging hand-held batteries by wireless power transmission from MW space solar power systems; (3) use of quasi-geostationary satellites to generate electricity and distribute it to targeted areas; and (4) architecture and technology for ultra-lightweight thin-film solar arrays with specific energy exceeding 1 kW/kg. This approach would yield flight demonstration of space solar power and wireless power transmission of 1.2 MW. This prototype system will be described, and a roadmap will be presented that will lead to still higher power levels.

  5. Investigating the Correlation Between Wind and Solar Power Forecast Errors in the Western Interconnection: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.; Hodge, B. M.; Florita, A.

    2013-05-01

    Wind and solar power generations differ from conventional energy generation because of the variable and uncertain nature of their power output. This variability and uncertainty can have significant impacts on grid operations. Thus, short-term forecasting of wind and solar generation is uniquely helpful for power system operations to balance supply and demand in an electricity system. This paper investigates the correlation between wind and solar power forecasting errors.

  6. Parametric analysis of a hybrid solar concentrating photovoltaic/concentrating solar power (CPV/CSP) system

    International Nuclear Information System (INIS)

    Han, Xue; Zhao, Guankun; Xu, Chao; Ju, Xing; Du, Xiaoze; Yang, Yongping

    2017-01-01

    Highlights: • Performance of the hybrid system is evaluated with the energy and exergy analyses. • Trapezoidal-shaped distribution of concentrated radiation flux density is adopted. • Effects of the influencing factors are investigated to optimize the design parameters. • Performance and reliability of the system with various DNIs are also discussed. - Abstract: This paper presents a parametric study of a recently proposed concentrating photovoltaic/concentrating solar power (CPV/CSP) hybrid system based on the energy and exergy analyses. A steady-state physical model is established for the hybrid system to carry out the energy and exergy analyses, in which a more general trapezoidal-shaped distribution of concentrated solar energy flux density is employed. Effects of various parameters are investigated including the average optical concentration ratio, the outlet temperature of R134a from the solar thermal receiver, and the coolant saturation vapor temperature. The results show that the generating efficiency and the power output of the hybrid system can increase by about 20% compared with the CPV-alone system, which indicates that the proposed hybrid system has a great potential to increase the utilization ratio of solar energy. Increasing the average optical concentration ratio or decreasing the outlet temperature of R134a from the solar thermal receiver can result in evident increases of both the energy efficiency and the exergy efficiency of the hybrid system. It is also shown that the energy and exergy efficiencies of the organic Rankine cycle (ORC) subsystem are nearly independent of the Direct Normal Irradiance (DNI), and the hybrid system can be always operated with a high efficiency despite of the DNI change at different moments or days.

  7. PowerShades. Transparent photovoltaics and solar shading. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Bezzel, E. (PhotoSolar ApS, Taastrup (Denmark)); Univ. of Neuchatel, Institute of Microtechnology, Neuchatel (CH)); Savcor Denmark A/S, Ballerup (Denmark)); Chem-Tec Plating A/S, Uldum (Denmark)); Danish Technological Institute (DTI), Taastrup (Denmark))

    2008-06-15

    This report marks the end of the PSO funded R and D project PowerShades. The objective of the project has been to establish knowledge about the manufacturing of PowerShade transparent photovoltaics and to demonstrate the viability of PowerShade, both as a product and when considered a building element. It has not been the objective to demonstrate a full-scale manufacturing of PowerShade, but to establish the knowledge that enables industrial manufacturing. The overall objective of the project has been achieved, and the large majority of the milestones defined have been met to full extent. It has been shown that PowerShade photovoltaic cells with an electrical efficiency of 5% can be reached, and it is expected that future work will lead to even better efficiency. Also, it has been demonstrated by full size side by side comparison that PowerShade transparent photovoltaics may replace exterior solar shading devices without compromise to the thermal properties of the building. The project has identified a number of work areas that must be addressed before an industrial manufacturing can be established. The efficiency of the photovoltaic generator must be increased and the stability of the entire product documented. Also, some of the identified processing steps must be scaled in capacity before manufacturing can be considered. (author)

  8. A solar thermal electric power plant for small communities

    Science.gov (United States)

    Holl, R. J.

    1979-01-01

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

  9. Solar central receiver hybrid power system. Phase I study

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-11-01

    A management plan is presented for implementation during the Solar Central Receiver Hybrid Power System - Phase I study project. The project plan and the management controls that will be used to assure technically adequate, timely and cost effective performance of the work required to prepare the designated end products are described. Bechtel in-house controls and those to be used in directing the subcontractors are described. Phase I of the project consists of tradeoff studies, parametric analyses, and engineering studies leading to conceptual definition and evaluation of a commercial hybrid power system that has the potential for supplying economically competitive electric power to a utility grid in the 1985-1990 time frame. The scope also includes the preparation of a development plan for the resolution of technical uncertainties and the preparation of plans and a proposal for Phase II of the program. The technical approach will be based on a central receiver solar energy collection scheme which supplies thermal energy to a combined cycle, generating system, consisting of a gas turbine cycle combined with a steam bottoming cycle by means of a heat recovery steam generator.

  10. A procedure to size solar-powered irrigation (photoirrigation) schemes

    Energy Technology Data Exchange (ETDEWEB)

    Cuadros, F. [Universidad de Extremadura, Badajoz (Spain). Dpto e Fisica; Lopez-Rodriguez, F.; Marcos, A. [Universidad de Extremadura, Badajoz (Spain). Dpto de Expresion Grafica; Coello, J. [Universidad Agraria ' La Molina' , Lima (Peru)

    2004-04-01

    The high cost of photovoltaic solar power makes it necessary, before undertaking any subsequent study, to dimension photovoltaic installations as accurately as possible. We here present a procedure to estimate the required dimension of a photovoltaic installation designed to power a pumping system for the drip irrigation of an olive tree orchard in SW Spain. The method consists of three main stages: (1) One determines the irrigation requirements of the specific estate according to the characteristics of its soil-type and climate. (2) A hydraulic analysis of the pumping system is made according to the depth of the aquifer and the height needed to stabilize the pressure in the water distribution network. (3) Finally, one determines the peak photovoltaic power required to irrigate a 10 ha sub-plot of the estate taking into account the overall yield of the photovoltaic-pump-irrigation system. We call this arrangement 'photoirrigation', and believe that it may be of great utility to improve the output of such socially significant crops as olives and wine grapes, optimizing the use of water and solar energy resources at the same time as preserving the environment. (author)

  11. Cloud Instrument Powered by Solar Cell Sends Data to Pachube

    Directory of Open Access Journals (Sweden)

    Doru Ursutiu

    2010-11-01

    Full Text Available Despite the economic downturn, there have been quite a few new developments in the world of remote measurements lately. Tag4M (www.tag4m.com introduced the concept of cloud instrument where sensors connected to WiFi tags send data to off-the-shelf Access Points which are part of the WiFi infrastructure that exists in enterprises, retail outlets, factories, and warehouses. Access Points route the data to the Internet where specialized web applications receive the information for processing and display. One of these specialized web applications is Pachube, (http://www.pachube.com which bills itself as a “real-time data brokerage platform”. Pachube enables people to tag and share real time sensor data from objects, devices and spaces around the world. This article presents the pachube cloud instrument where sensors connected to Tag4M WiFi tags send digitized data to www.pachube.com for public display. The article contains very detailed analysis of the solar cell power source that is used to continuously power the Tag4M tag during this application. Cloud Instruments powered by solar cells enable people around the world to share real time sensor data using web pages on the Internet. This is a very interesting and exciting technology development that we want to bring to your attention.

  12. Solar Dynamic Power System Stability Analysis and Control

    Science.gov (United States)

    Momoh, James A.; Wang, Yanchun

    1996-01-01

    The objective of this research is to conduct dynamic analysis, control design, and control performance test of solar power system. Solar power system consists of generation system and distribution network system. A bench mark system is used in this research, which includes a generator with excitation system and governor, an ac/dc converter, six DDCU's and forty-eight loads. A detailed model is used for modeling generator. Excitation system is represented by a third order model. DDCU is represented by a seventh order system. The load is modeled by the combination of constant power and constant impedance. Eigen-analysis and eigen-sensitivity analysis are used for system dynamic analysis. The effects of excitation system, governor, ac/dc converter control, and the type of load on system stability are discussed. In order to improve system transient stability, nonlinear ac/dc converter control is introduced. The direct linearization method is used for control design. The dynamic analysis results show that these controls affect system stability in different ways. The parameter coordination of controllers are recommended based on the dynamic analysis. It is concluded from the present studies that system stability is improved by the coordination of control parameters and the nonlinear ac/dc converter control stabilize system oscillation caused by the load change and system fault efficiently.

  13. Non-Radioisotope Power Systems For Sunless Solar System Exploration Missions

    Data.gov (United States)

    National Aeronautics and Space Administration — Several targets of interest in solar system exploration require non-solar power sources due to permanent shading or extreme distance from the sun. This study will...

  14. High-power all fiber-integrated linearly polarized picosecond ytterbium-doped master-oscillator power amplifier

    Science.gov (United States)

    Hong, Chang; Liu, Jiang; Sun, Ruoyu; Shi, Yuhang; Wang, Yu; Wang, Pu

    2018-01-01

    We demonstrated an all-fiber-integrated linearly-polarized picosecond ytterbium-doped master-oscillator power-amplifier system, which yielded 225-W of average output power and the corresponding slope efficiency is 70.5%. The seed source was a compact passively mode-locked polarization-maintaining ytterbium-doped all-fiber oscillator with a pulse duration of 80-ps at 58.2-MHz repetition rate. In combination with two pre-amplifiers and a large-mode-area polarization-maintaining ytterbium-doped all-fiber master amplifier, output pulse energy up to 3.8-μJ with 48.3-kW pulse peak power was obtained without the need of complex free-space coupling and output setups. The polarization extinction ratio were measured to be 14.5 dB and the beam quality M2 factors was less than 1.49 in the both orthogonal directions at maximum output power.

  15. DIRECT OBSERVATION OF SOLAR CORONAL MAGNETIC FIELDS BY VECTOR TOMOGRAPHY OF THE CORONAL EMISSION LINE POLARIZATIONS

    International Nuclear Information System (INIS)

    Kramar, M.; Lin, H.; Tomczyk, S.

    2016-01-01

    We present the first direct “observation” of the global-scale, 3D coronal magnetic fields of Carrington Rotation (CR) Cycle 2112 using vector tomographic inversion techniques. The vector tomographic inversion uses measurements of the Fe xiii 10747 Å Hanle effect polarization signals by the Coronal Multichannel Polarimeter (CoMP) and 3D coronal density and temperature derived from scalar tomographic inversion of Solar Terrestrial Relations Observatory (STEREO)/Extreme Ultraviolet Imager (EUVI) coronal emission lines (CELs) intensity images as inputs to derive a coronal magnetic field model that best reproduces the observed polarization signals. While independent verifications of the vector tomography results cannot be performed, we compared the tomography inverted coronal magnetic fields with those constructed by magnetohydrodynamic (MHD) simulations based on observed photospheric magnetic fields of CR 2112 and 2113. We found that the MHD model for CR 2112 is qualitatively consistent with the tomography inverted result for most of the reconstruction domain except for several regions. Particularly, for one of the most noticeable regions, we found that the MHD simulation for CR 2113 predicted a model that more closely resembles the vector tomography inverted magnetic fields. In another case, our tomographic reconstruction predicted an open magnetic field at a region where a coronal hole can be seen directly from a STEREO-B/EUVI image. We discuss the utilities and limitations of the tomographic inversion technique, and present ideas for future developments

  16. Possible effect of extreme solar energetic particle events of September–October 1989 on polar stratospheric aerosols: a case study

    Directory of Open Access Journals (Sweden)

    I. A. Mironova

    2013-09-01

    Full Text Available The main ionization source of the middle and low Earth's atmosphere is related to energetic particles coming from outer space. Usually it is ionization from cosmic rays that is always present in the atmosphere. But in a case of a very strong solar eruption, some solar energetic particles (SEPs can reach middle/low atmosphere increasing the ionization rate up to some orders of magnitude at polar latitudes. We continue investigating such a special class of solar events and their possible applications for natural variations of the aerosol content. After the case study of the extreme SEP event of January 2005 and its possible effect upon polar stratospheric aerosols, here we analyze atmospheric applications of the sequence of several events that took place over autumn 1989. Using aerosol data obtained over polar regions from two satellites with space-borne optical instruments SAGE II and SAM II that were operating during September–October 1989, we found that an extreme major SEP event might have led to formation of new particles and/or growth of preexisting ultrafine particles in the polar stratospheric region. However, the effect of the additional ambient air ionization on the aerosol formation is minor, in comparison with temperature effect, and can take place only in the cold polar atmospheric conditions. The extra aerosol mass formed under the temperature effect allows attributing most of the changes to the "ion–aerosol clear sky mechanism".

  17. False Dawn of a Solar Age: A History of Solar Heating and Power During the Energy Crisis, 1973-1986

    Science.gov (United States)

    Scavo, Jordan Michael

    The unfolding of the energy crisis in the early 1970s brought solar to the fore as a topic for national discussion. National dialogues about solar power and national energy policy were one way that Americans interpreted their present and envisioned their nation's future. Yet, policy makers and the general public considered alternative energies, including solar, largely based on the economic conditions of their eras, considerations that, at least until the Reagan era, often transcended political ideologies and parties. Energy prices and the emerging political expediency of replacing fossil fuels were the primary drivers in shaping federal energy policies and public interest during this era. Enthusiasm for solar power often corresponded to the market price of petroleum. By the late 1970s, a lot of people believed the same. Amid growing public enthusiasm, President Carter eventually came out strongly in favor of solar energy, mounting solar panels on the White House and unveiling a plan to procure 20% of the nation's energy from the sun by the year 2000. During the 1960s and 1970s, Americans changed their energy values in response to concerns over environmentalism and the antinuclear movement. Pollution, environmental disasters, and energy crises during the 1960s and 1970s brought terms like "clean energy" and "renewable energy" into the national lexicon, and solar often served as the most prominent symbol of those ideas. At the same time, advocates presented solar as a stark contrast to nuclear: solar energy made life on earth possible; nuclear energy made it perilous. Science fiction and futurism shaped the American popular imagination through its presentation of solar technology. Each genre suffused the other and ingrained in the American national consciousness a sense of grandiose wonderment about the potential for solar energy, a potential that often did not match the contemporary applications for solar technology. The emergence of solar industries alarmed oil

  18. Space Solar Power Satellite Technology Development at the Glenn Research Center: An Overview

    Science.gov (United States)

    Dudenhoefer, James E.; George, Patrick J.

    2000-01-01

    NASA Glenn Research Center (GRC). is participating in the Space Solar Power Exploratory Research and Technology program (SERT) for the development of a solar power satellite concept. The aim of the program is to provide electrical power to Earth by converting the Sun's energy and beaming it to the surface. This paper will give an overall view of the technologies being pursued at GRC including thin film photovoltaics, solar dynamic power systems, space environmental effects, power management and distribution, and electric propulsion. The developmental path not only provides solutions to gigawatt sized space power systems for the future, but provides synergistic opportunities for contemporary space power architectures. More details of Space Solar Power can be found by reading the references sited in this paper and by connecting to the web site http://moonbase.msfc.nasa.gov/ and accessing the "Space Solar Power" section "Public Access" area.

  19. Convex relaxation of Optimal Power Flow in Distribution Feeders with embedded solar power

    DEFF Research Database (Denmark)

    Hermann, Alexander Niels August; Wu, Qiuwei; Huang, Shaojun

    2016-01-01

    There is an increasing interest in using Distributed Energy Resources (DER) directly coupled to end user distribution feeders. This poses an array of challenges because most of today’s distribution feeders are designed for unidirectional power flow. Therefore when installing DERs such as solar...... panels with uncontrolled inverters, the upper limit of installable capacity is quickly reached in many of today’s distribution feeders. This problem can often be mitigated by optimally controlling the voltage angles of inverters. However, the optimal power flow problem in its standard form is a large...... scale non-convex optimization problem, and thus can’t be solved precisely and also is computationally heavy and intractable for large systems. This paper examines the use of a convex relaxation using Semi-definite programming to optimally control solar power inverters in a distribution grid in order...

  20. Peeled film GaAs solar cells for space power

    Science.gov (United States)

    Wilt, D. M.; Deangelo, F. L.; Thomas, R. D.; Bailey, S. G.; Landis, G. A.; Brinker, D. J.; Fatemi, N. S.

    1990-01-01

    Gallium arsenide (GaAs) peeled film solar cells were fabricated, by Organo-Metallic Vapor Phase Epitaxy (OMVPE), incorporating an aluminum arsenide (AlAs) parting layer between the device structure and the GaAs substrate. This layer was selectively removed by etching in dilute hydrofloric (HF) acid to release the epitaxial film. Test devices exhibit high series resistance due to insufficient back contact area. A new design is presented which uses a coverglass superstrate for structural support and incorporates a coplanar back contact design. Devices based on this design should have a specific power approaching 700 W/Kg.

  1. SPS market analysis. [small solar thermal power systems

    Science.gov (United States)

    Goff, H. C.

    1980-01-01

    A market analysis task included personal interviews by GE personnel and supplemental mail surveys to acquire statistical data and to identify and measure attitudes, reactions and intentions of prospective small solar thermal power systems (SPS) users. Over 500 firms were contacted, including three ownership classes of electric utilities, industrial firms in the top SIC codes for energy consumption, and design engineering firms. A market demand model was developed which utilizes the data base developed by personal interviews and surveys, and projected energy price and consumption data to perform sensitivity analyses and estimate potential markets for SPS.

  2. Photovoltaic and thermal energy conversion for solar powered satellites

    Science.gov (United States)

    Von Tiesenhausen, G. F.

    1976-01-01

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

  3. Peeled film GaAs solar cells for space power

    Science.gov (United States)

    Wilt, D. M.; Deangelo, F. L.; Thomas, R. D.; Bailey, S. G.; Landis, G. A.; Brinker, D. J.; Fatemi, N. S.

    1990-05-01

    Gallium arsenide (GaAs) peeled film solar cells were fabricated, by Organo-Metallic Vapor Phase Epitaxy (OMVPE), incorporating an aluminum arsenide (AlAs) parting layer between the device structure and the GaAs substrate. This layer was selectively removed by etching in dilute hydrofloric (HF) acid to release the epitaxial film. Test devices exhibit high series resistance due to insufficient back contact area. A new design is presented which uses a coverglass superstrate for structural support and incorporates a coplanar back contact design. Devices based on this design should have a specific power approaching 700 W/Kg.

  4. A planet in a polar orbit of 1.4 solar-mass star

    Directory of Open Access Journals (Sweden)

    Guenther E.W.

    2015-01-01

    Full Text Available Although more than a thousand transiting extrasolar planets have been discovered, only very few of them orbit stars that are more massive than the Sun. The discovery of such planets is interesting, because they have formed in disks that are more massive but had a shorter life time than those of solar-like stars. Studies of planets more massive than the Sun thus tell us how the properties of the proto-planetary disks effect the formation of planets. Another aspect that makes these planets interesting is that they have kept their original orbital inclinations. By studying them we can thus find out whether the orbital axes planets are initially aligned to the stars rotational axes, or not. Here we report on the discovery of a planet of a 1.4 solar-mass star with a period of 5.6 days in a polar orbit made by CoRoT. This new planet thus is one of the few known close-in planets orbiting a star that is substantially more massive than the Sun.

  5. Cost competitiveness of a solar cell array power source for ATS-6 educational TV terminal

    Science.gov (United States)

    Masters, R. M.

    1975-01-01

    A cost comparison is made between a terrestrial solar cell array power system and a variety of other power sources for the ATS-6 Satellite Instructional Television Experiment (SITE) TV terminals in India. The solar array system was sized for a typical Indian location, Lahore. Based on present capital and fuel costs, the solar cell array power system is a close competitor to the least expensive alternate power system. A feasibility demonstration of a terrestrial solar cell array system powering an ATS-6 receiver terminal at Cleveland, Ohio is described.

  6. Evaluation of the cooking power in three different solar cookers box-type

    Science.gov (United States)

    Terres, H.; Lizardi, A.; Chávez, S.; López, R.; Vaca, M.

    2017-01-01

    In the present work calculations for the cooking power in three different solar cookers are shown. The designs considered for the solar cookers are square, rectangular and octagonal. Agree to the results, a solar cooker with larger area for the solar radiation inlet has the biggest cooking power. The cooking powers obtained for the solar cookers are 4.04 W (0.49 m2), 2.06 W (0.15 m2) and 0.88 W (0.19 m2) which correspond to square, rectangular and octagonal designs respectively. For the evaluation, the standard ASAE S580 JAN03 was considered to evaluate the cooking power in the solar cookers. Following the method established in this standard was possible to calculate the cooking power and evaluate the solar cookers at the same time. This activity except for what has been done in the standard, have not been done in other works.

  7. Evaluation of the cooking power in three different solar cookers box-type

    International Nuclear Information System (INIS)

    Terres, H; Lizardi, A; Chávez, S; López, R; Vaca, M

    2017-01-01

    In the present work calculations for the cooking power in three different solar cookers are shown. The designs considered for the solar cookers are square, rectangular and octagonal. Agree to the results, a solar cooker with larger area for the solar radiation inlet has the biggest cooking power. The cooking powers obtained for the solar cookers are 4.04 W (0.49 m"2), 2.06 W (0.15 m"2) and 0.88 W (0.19 m"2) which correspond to square, rectangular and octagonal designs respectively. For the evaluation, the standard ASAE S580 JAN03 was considered to evaluate the cooking power in the solar cookers. Following the method established in this standard was possible to calculate the cooking power and evaluate the solar cookers at the same time. This activity except for what has been done in the standard, have not been done in other works. (paper)

  8. Solar power engineering in the future world: A view from Russia

    International Nuclear Information System (INIS)

    Strebkov, D. S.

    2012-01-01

    The paper suggests an energy model for the future world based on solar power engineering and new Russian energy technologies. Chlorine-free solar silicon technologies, stationary concentrators, solar modules with service lives doubled up to 40 years, matrix solar elements with an efficiency factor of 20% at a concentration of 5-500, and resonance waveguide methods for transmitting energy for solar energy systems are considered. (author)

  9. Passive solar power in the shade of French energy policy, 1945-1986

    International Nuclear Information System (INIS)

    Teissier, Pierre

    2013-01-01

    The installation in 1949 of the LES (solar energy laboratory) on Mont Louis-Odeillo in the Pyrenees, was emblematic of public commitment to passive solar power. Throughout the 1950's solar furnaces were supported for research into materials and solar powered homes, moving in phase with colonial policy. Then, with the construction at Odeillo of a giant solar furnace as part of the 'policy of grandeur', policy swung in the opposite direction. The study concludes with the role that the LES played at the time of the energy crisis in the 1970's and questions the French model of not developing solar energy

  10. Univariate Time Series Prediction of Solar Power Using a Hybrid Wavelet-ARMA-NARX Prediction Method

    Energy Technology Data Exchange (ETDEWEB)

    Nazaripouya, Hamidreza; Wang, Yubo; Chu, Chi-Cheng; Pota, Hemanshu; Gadh, Rajit

    2016-05-02

    This paper proposes a new hybrid method for super short-term solar power prediction. Solar output power usually has a complex, nonstationary, and nonlinear characteristic due to intermittent and time varying behavior of solar radiance. In addition, solar power dynamics is fast and is inertia less. An accurate super short-time prediction is required to compensate for the fluctuations and reduce the impact of solar power penetration on the power system. The objective is to predict one step-ahead solar power generation based only on historical solar power time series data. The proposed method incorporates discrete wavelet transform (DWT), Auto-Regressive Moving Average (ARMA) models, and Recurrent Neural Networks (RNN), while the RNN architecture is based on Nonlinear Auto-Regressive models with eXogenous inputs (NARX). The wavelet transform is utilized to decompose the solar power time series into a set of richer-behaved forming series for prediction. ARMA model is employed as a linear predictor while NARX is used as a nonlinear pattern recognition tool to estimate and compensate the error of wavelet-ARMA prediction. The proposed method is applied to the data captured from UCLA solar PV panels and the results are compared with some of the common and most recent solar power prediction methods. The results validate the effectiveness of the proposed approach and show a considerable improvement in the prediction precision.

  11. Ultra-Portable Solar-Powered 3D Printers for Onsite Manufacturing of Medical Resources.

    Science.gov (United States)

    Wong, Julielynn Y

    2015-09-01

    The first space-based fused deposition modeling (FDM) 3D printer is powered by solar photovoltaics. This study seeks to demonstrate the feasibility of using solar energy to power a FDM 3D printer to manufacture medical resources at the Mars Desert Research Station and to design an ultra-portable solar-powered 3D printer for off-grid environments. Six solar panels in a 3×2 configuration, a voltage regulator/capacitor improvised from a power adapter, and two 12V batteries in series were connected to power a FDM 3D printer. Three designs were printed onsite and evaluated by experts post analogue mission. A solar-powered 3D printer composed of off-the-shelf components was designed to be transported in airline carry-on luggage. During the analogue mission, the solar-powered printer could only be operated for printer was designed that could print an estimated 16 dental tools or 8 mallet finger splints or 7 scalpel handles on one fully charged 12V 150Wh battery with a 110V AC converter. It is feasible to use solar energy to power a 3D printer to manufacture functional and personalized medical resources at a Mars analogue research station. Based on these findings, a solar-powered suitcase 3D printing system containing solar panels, 12V battery with charge controller and AC inverter, and back-up solar charge controller and inverter was designed for transport to and use in off-grid communities.

  12. Data-driven modeling of solar-powered urban microgrids.

    Science.gov (United States)

    Halu, Arda; Scala, Antonio; Khiyami, Abdulaziz; González, Marta C

    2016-01-01

    Distributed generation takes center stage in today's rapidly changing energy landscape. Particularly, locally matching demand and generation in the form of microgrids is becoming a promising alternative to the central distribution paradigm. Infrastructure networks have long been a major focus of complex networks research with their spatial considerations. We present a systemic study of solar-powered microgrids in the urban context, obeying real hourly consumption patterns and spatial constraints of the city. We propose a microgrid model and study its citywide implementation, identifying the self-sufficiency and temporal properties of microgrids. Using a simple optimization scheme, we find microgrid configurations that result in increased resilience under cost constraints. We characterize load-related failures solving power flows in the networks, and we show the robustness behavior of urban microgrids with respect to optimization using percolation methods. Our findings hint at the existence of an optimal balance between cost and robustness in urban microgrids.

  13. The use of solar energy for powering a portable autoclave.

    Science.gov (United States)

    Dravid, M N; Chandak, A; Phute, S U; Khadse, R K; Adchitre, H R; Kulkarni, S D

    2012-04-01

    Climate change and the depletion of fossil fuels have forced the developed world to look for clean energy alternatives. Solar cooking is developing in Asian and African countries blessed with ample sun, but is still at an early stage. A portable autoclave was developed in India using this technology. The Prince-40 Concentrator provided adequate capacity to autoclave culture media and treat biomedical waste in a small laboratory set-up, and could save electricity worth Rs. 15,000 (188.10 GBP)/year or LPG worth Rs. 37,500 (470.25 GBP)/year. This technology would be of immense use in health centres in rural areas with frequent power cuts or no power supply. Copyright © 2012 The Healthcare Infection Society. Published by Elsevier Ltd. All rights reserved.

  14. Simultaneously improving optical absorption of both transverse-electric polarized and transverse-magnetic polarized light for organic solar cells with Ag grating used as transparent electrode

    Directory of Open Access Journals (Sweden)

    Yongbing Long

    2014-08-01

    Full Text Available Theoretical simulations are performed to investigate optical performance of organic solar cells with Ag grating electrode. It is demonstrated that optical absorption for both transverse-electric (TE polarized and transverse-magnetic(TM polarized light is simultaneously improved when compared with that for the device without the Ag grating. The improvement is respectively attributed to the resonance and the surface plasmon polaritons within the device. After an additional WO3 layer is capped on the Ag grating, absorption of TE-polarized light is further improved due to resonance of double microcavities within the device, and absorption of TM-polarized light is improved by the combined effects of the microcavity resonance and the surface plasmon polaritons. Correspondingly, the short current density for randomly polarized light is improved by 18.1% from that of the device without the Ag grating. Finally, it is demonstrated that high transmission may not be an essential prerequisite for metallic gratings when they are used as transparent electrode since absorption loss caused by low transmission can be compensated by using a capping layer to optimize optical resonance of the WMC structure within the device.

  15. Solar radiation concentrators paired with multijunction photoelectric converters in ground-based solar power plants (Part II)

    Science.gov (United States)

    Ionova, E. A.; Ulanov, M. V.; Davidyuk, N. Yu.; Sadchikov, N. A.

    2017-04-01

    The present work is devoted to determining the conditions of the joint operation of photoelectric converter-solar concentrator pairs, which are used in solar power plants with concentrators. Three-cascade photoconverters based on A3B5 materials with different distributions of solar radiation in spectral ranges are studied. Concentrators of solar radiation are designed as the Fresnel lenses with silicon-on-glass structure. Refractive lens profile fabricated on the basis of Wacker RT604 silicone rubber is characterized by significant changes in refractive index with temperature. The effect of geometric parameters of the Fresnel lenses and their operating temperature on characteristics of solar radiation concentration in specified spectral intervals have been examined. The parameters of concentrators being paired with a photoelectric converter, which may ensure the efficient functioning of the solar power plant, have been calculated.

  16. Concentrated solar power (CSP innovation analysis in South Africa

    Directory of Open Access Journals (Sweden)

    Craig, Toyosi Onalapo

    2017-08-01

    Full Text Available South Africa aims to generate 42 per cent of its electricity from renewable energy technology sources by 2030. Concentrating solar power (CSP is one of the major renewable energy technologies that have been prioritised by South Africa, given the abundant solar resources available in the region. Seven CSP plants have been, or are being, built; three of them are already connected to the national grid. However, the impacts of this technology on South African research, development, and innovation have not been investigated to date. This paper thus analyses the CSP technologies in South Africa in terms of the existing technology adoption models and diffusion strategies, used by government and its agencies, to improve the development and deployment of these technologies. It is found that CSP has been treated generally like other renewable energy technologies through the Renewable Energy Independent Power Producer Procurement Programme (REIPPPP, although a tariff plan for CSP plants of the future has been made. No specific technology diffusion or adoption model for CSP was found; so this paper explores how it can be developed.

  17. Designing a solar powered Stirling heat engine based on multiple criteria: Maximized thermal efficiency and power

    International Nuclear Information System (INIS)

    Ahmadi, Mohammad Hossein; Sayyaadi, Hoseyn; Dehghani, Saeed; Hosseinzade, Hadi

    2013-01-01

    Highlights: • Thermodynamic model of a solar-dish Stirling engine was presented. • Thermal efficiency and output power of the engine were simultaneously maximized. • A final optimal solution was selected using several decision-making methods. • An optimal solution with least deviation from the ideal design was obtained. • Optimal solutions showed high sensitivity against variation of system parameters. - Abstract: A solar-powered high temperature differential Stirling engine was considered for optimization using multiple criteria. A thermal model was developed so that the output power and thermal efficiency of the solar Stirling system with finite rate of heat transfer, regenerative heat loss, conductive thermal bridging loss, finite regeneration process time and imperfect performance of the dish collector could be obtained. The output power and overall thermal efficiency were considered for simultaneous maximization. Multi-objective evolutionary algorithms (MOEAs) based on the NSGA-II algorithm were employed while the solar absorber temperature and the highest and lowest temperatures of the working fluid were considered the decision variables. The Pareto optimal frontier was obtained and a final optimal solution was also selected using various decision-making methods including the fuzzy Bellman–Zadeh, LINMAP and TOPSIS. It was found that multi-objective optimization could yield results with a relatively low deviation from the ideal solution in comparison to the conventional single objective approach. Furthermore, it was shown that, if the weight of thermal efficiency as one of the objective functions is considered to be greater than weight of the power objective, lower absorber temperature and low temperature ratio should be considered in the design of the Stirling engine

  18. Performance Analysis and Optimization of a Solar Powered Stirling Engine with Heat Transfer Considerations

    OpenAIRE

    Chieh-Li Chen; Chia-En Ho; Her-Terng Yau

    2012-01-01

    This paper investigates the optimization of the performance of a solar powered Stirling engine based on finite-time thermodynamics. Heat transference in the heat exchangers between a concentrating solar collector and the Stirling engine is studied. The irreversibility of a Stirling engine is considered with the heat transfer following Newton's law. The power generated by a Stirling engine is used as an objective function for maximum power output design with the concentrating solar collec...

  19. Analyzing the Impact of Solar Power on Multi-Hourly Thermal Generator Ramping

    Energy Technology Data Exchange (ETDEWEB)

    Rosenkranz, Joshua-Benedict; Brancucci Martinez-Anido, Carlo; Hodge, Bri-Mathias

    2016-04-08

    Solar power generation, unlike conventional forms of electricity generation, has higher variability and uncertainty in its output because solar plant output is strongly impacted by weather. As the penetration rate of solar capacity increases, grid operators are increasingly concerned about accommodating the increased variability and uncertainty that solar power provides. This paper illustrates the impacts of increasing solar power penetration on the ramping of conventional electricity generators by simulating the operation of the Independent System Operator -- New England power system. A production cost model was used to simulate the power system under five different scenarios, one without solar power and four with increasing solar power penetrations up to 18%, in terms of annual energy. The impact of solar power is analyzed on six different temporal intervals, including hourly and multi-hourly (2- to 6-hour) ramping. The results show how the integration of solar power increases the 1- to 6-hour ramping events of the net load (electric load minus solar power). The study also analyzes the impact of solar power on the distribution of multi-hourly ramping events of fossil-fueled generators and shows increasing 1- to 6-hour ramping events for all different generators. Generators with higher ramp rates such as gas and oil turbine and internal combustion engine generators increased their ramping events by 200% to 280%. For other generator types--including gas combined-cycle generators, coal steam turbine generators, and gas and oil steam turbine generators--more and higher ramping events occurred as well for higher solar power penetration levels.

  20. Efficiency enhancement using voltage biasing for ferroelectric polarization in dye-sensitized solar cells

    Science.gov (United States)

    Kim, Sangmo; Song, Myoung Geun; Bark, Chung Wung

    2018-01-01

    Dye-sensitized solar cells (DSSCs) are one of the most promising third generation solar cells that have been extensively researched over the past decade as alternative to silicon-based solar cells, due to their low production cost and high energy-conversion efficiency. In general, a DSSC consists of a transparent electrode, a counter electrode, and an electrolyte such as dye. To achieve high power-conversion efficiency in cells, many research groups have focused their efforts on developing efficient dyes for liquid electrolytes. In this work, we report on the photovoltaic properties of DSSCs fabricated using a mixture of TiO2 with nanosized Fe-doped bismuth lanthanum titanate (nFe-BLT) powder). Firstly, nFe-BLT powders were prepared using a high-energy ball milling process and then, TiO2 and nFe-BLT powders were stoichiometrically blended. Direct current (DC) bias of 20 MV/m was applied to lab-made DSSCs. With the optimal concentration of nFe-BLT doped in the electrode, their light-to-electricity conversion efficiency could be improved by ∼64% compared with DSSCs where no DC bias was applied.

  1. Fuzzy Controller for a Voltage-Regulated Solar-Powered MPPT System for Hybrid Power System Applications

    Directory of Open Access Journals (Sweden)

    Jaw-Kuen Shiau

    2015-04-01

    Full Text Available This paper presents the design of a fuzzy-logic-based voltage-regulated solar power maximum power point tracking (MPPT system for applications involving hybrid power systems. The system contains a solar power system and battery as the primary and secondary power sources, respectively. The solar system alone supplies power to the electric motor and maintains the output voltage at a predetermined level when it has sufficient power. When the solar power is insufficient, the solar system is operated at its maximum power point (MPP and the battery is engaged to compensate for the insufficiency. First, a variant of the incremental conductance MPP condition was established. Under the MPP condition, the voltage-regulated MPPT system was formulated as a feedback control system, where the MPP condition and voltage regulation requirements were used as the system inputs. Next, a fuzzy controller was developed to perform the voltage-regulated MPPT function for the hybrid power system. A simulation model based on Matrix laboratory (MATLAB/SIMULINK (a block diagram environment for multi-domain simulation and model-based design and a piecewise linear electric circuit simulation (PLECS tool for controlling the dc motor velocity was developed to verify the voltage-regulated solar power MPPT system.

  2. A review of solar energy based heat and power generation systems

    DEFF Research Database (Denmark)

    Modi, Anish; Bühler, Fabian; Andreasen, Jesper Graa

    2017-01-01

    The utilization of solar energy based technologies has attracted increased interest in recent times in order to satisfy the various energy demands of our society. This paper presents a thorough review of the open literature on solar energy based heat and power plants. In order to limit the scope...... of the review, only fully renewable plants with at least the production of electricity and heat/hot water for end use are considered. These include solar photovoltaic and solar thermal based plants with both concentrating and non-concentrating collectors in both solar-only and solar-hybrid configurations....... The paper also presents a selection of case studies for the evaluation of solar energy based combined heat and power generation possibility in Denmark. The considered technologies for the case studies are (1) solar photovoltaic modules, (2) solar flat plate collectors, (3) a ground source heat pump, (4...

  3. Concerning tests of time-reversal invariance via the polarization-analyzing power equality

    International Nuclear Information System (INIS)

    Conzett, H.E.

    1982-01-01

    Previous tests of time-reversal invariance via comparisons of polarizations and analyzing powers in nuclear scattering have been examined. It is found that all of these comparisons fail as adequate tests of time-reversal invariance either because of a lack of experimental precision or the lack of sensitivity to any time-reversal symmetry violation

  4. Power generation plant integrating concentrated solar power receiver and pressurized heat exchanger

    Science.gov (United States)

    Sakadjian, Bartev B; Flynn, Thomas J; Hu, Shengteng; Velazquez-Vargas, Luis G; Maryamchik, Mikhail

    2016-10-04

    A power plant includes a solar receiver heating solid particles, a standpipe receiving solid particles from the solar receiver, a pressurized heat exchanger heating working fluid by heat transfer through direct contact with heated solid particles flowing out of the bottom of the standpipe, and a flow path for solid particles from the bottom of the standpipe into the pressurized heat exchanger that is sealed by a pressure P produced at the bottom of the standpipe by a column of heated solid particles of height H. The flow path may include a silo or surge tank comprising a pressure vessel connected to the bottom of the standpipe, and a non-mechanical valve. The power plant may further include a turbine driven by heated working fluid discharged from the pressurized heat exchanger, and a compressor driven by the turbine.

  5. Concentrated solar power generation: Firm and dispatchable capacity for Brazil's solar future?

    Science.gov (United States)

    Tomaschek, Jan; Haasz, Thomas; Fahl, Ulrich

    2016-05-01

    The Brazilian electricity mix is currently dominated by renewable energy forms, foremost hydropower. Large additional capacity demands are expected in the mid-term future but additional potential for hydro power is limited. In addition it is planned to construct more than 17 GW of wind power and additional capacity of photovoltaics (PV). Due to the fluctuating nature of such renewables, however, wind and PV are hardly able to provide firm capacity. Concentrated solar power (CSP) might be a feasible option to provide firm and dispatchable capacity at low carbon emissions. This study analyses the opportunities for integrating CSP into the Brazilian energy system. Making use of the TiPS-B model, a novel application of the optimization model generator TIMES, we compare different climate protection strategies with a reference scenario and analyze the contribution of CSP to the electricity mix. The analysis covers various types of CSP power plants with molten salt energy storage where we look at possible dispatch strategies considering the fluctuations in electricity supply and use. The consideration of solar water heaters (SWH) is the first step to transfer the power system model to an energy system model that is capable of showing the benefits of energy saving measures on the demand side. It can be demonstrated that the Brazilian power system is likely to change significantly in future. This development would go hand in hand with a strong increase in carbon emissions if no mitigation actions are taken and fossil fueled power plants are used to fill the gap in capacity. CSP power plants are found as a feasible alternative for covering the demand while taking carbon mitigation actions. In a scenario, aiming at 4 and 2 degrees global warming, CSP provides for 7.6 GW and 14.6 GW capacity in 2050, respectively. Different storage configurations are used to provide energy in the evening hours to cover the demand peak providing a strong benefit over photovoltaic electricity

  6. Dependence of InGaN solar cell performance on polarization-induced electric field and carrier lifetime

    International Nuclear Information System (INIS)

    Yang Jing; Zhao De-Gang; Jiang De-Sheng; Liu Zong-Shun; Chen Ping; Li Liang; Wu Liang-Liang; Le Ling-Cong; Li Xiao-Jing; He Xiao-Guang; Yang Hui; Wang Hui; Zhu Jian-Jun; Zhang Shu-Ming; Zhang Bao-Shun

    2013-01-01

    The effects of Mg-induced net acceptor doping concentration and carrier lifetime on the performance of a p—i—n InGaN solar cell are investigated. It is found that the electric field induced by spontaneous and piezoelectric polarization in the i-region could be totally shielded when the Mg-induced net acceptor doping concentration is sufficiently high. The polarization-induced potential barriers are reduced and the short circuit current density is remarkably increased from 0.21 mA/cm 2 to 0.95 mA/cm 2 by elevating the Mg doping concentration. The carrier lifetime determined by defect density of i-InGaN also plays an important role in determining the photovoltaic properties of solar cell. The short circuit current density severely degrades, and the performance of InGaN solar cell becomes more sensitive to the polarization when carrier lifetime is lower than the transit time. This study demonstrates that the crystal quality of InGaN absorption layer is one of the most important challenges in realizing high efficiency InGaN solar cells. (interdisciplinary physics and related areas of science and technology)

  7. Circuit Simulation for Solar Power Maximum Power Point Tracking with Different Buck-Boost Converter Topologies

    Directory of Open Access Journals (Sweden)

    Jaw-Kuen Shiau

    2014-08-01

    Full Text Available The power converter is one of the essential elements for effective use of renewable power sources. This paper focuses on the development of a circuit simulation model for maximum power point tracking (MPPT evaluation of solar power that involves using different buck-boost power converter topologies; including SEPIC, Zeta, and four-switch type buck-boost DC/DC converters. The circuit simulation model mainly includes three subsystems: a PV model; a buck-boost converter-based MPPT system; and a fuzzy logic MPPT controller. Dynamic analyses of the current-fed buck-boost converter systems are conducted and results are presented in the paper. The maximum power point tracking function is achieved through appropriate control of the power switches of the power converter. A fuzzy logic controller is developed to perform the MPPT function for obtaining maximum power from the PV panel. The MATLAB-based Simulink piecewise linear electric circuit simulation tool is used to verify the complete circuit simulation model.

  8. A Novel Extension Decision-Making Method for Selecting Solar Power Systems

    Directory of Open Access Journals (Sweden)

    Meng-Hui Wang

    2013-01-01

    Full Text Available Due to the complex parameters of a solar power system, the designer not only must think about the load demand but also needs to consider the price, weight, and annual power generating capacity (APGC and maximum power of the solar system. It is an important task to find the optimal solar power system with many parameters. Therefore, this paper presents a novel decision-making method based on the extension theory; we call it extension decision-making method (EDMM. Using the EDMM can make it quick to select the optimal solar power system. The paper proposed this method not only to provide a useful estimated tool for the solar system engineers but also to supply the important reference with the installation of solar systems to the consumer.

  9. Measurements of size and composition of particles in polar stratospheric clouds from infrared solar absorption spectra

    International Nuclear Information System (INIS)

    Kinne, S.; Toon, O.B.; Toon, G.C.; Farmer, C.B.; Browell, E.V.; McCormick, M.P.

    1989-01-01

    The attenuation of solar radiation between 1.8- and 15-μm wavelength was measured with the airborne Jet Propulsion Laboratory Mark IV interferometer during the Airborne Antarctic Ozone Expedition in 1987. The measurements not only provide information about the abundance of stratospheric gases, but also about the optical depths of polar stratospheric clouds (PSCs) at wavelengths of negligible gas absorption. The spectral dependence of the PSC optical depth contains information about PSC particle size and particle composition. Thirty-three PSC cases were analyzed and categorized into two types. Type I clouds contain particles with radii of about 0.5 μm and nitric acid concentrations greater than 40%. Type II clouds contain particles composed of water ice with radii of 6 μm and larger. Cloud altitudes were determined from 1.064-μm backscattering observations of the airborne Langley DIAL lidar system. Based on the PSC geometrical thickness, both mass and particle density were estimated. Type I clouds typically had visible wavelength optical depths of about 0.008, mass densities of about 20 ppb, and about 2 particles/cm 3 . The observed type II clouds had optical depths of about 0.03, mass densities of about 400 ppb mass, and about 0.03 particles/cm 3 . The detected PSC type I clouds extended to altitudes of 21 km and were nearly in the ozone-depleted region of the polar stratosphere. The observed type II cases during September were predominantly found at altitudes below 15 km

  10. Crosbyton Solar Power Project. Volume 8: Preliminary design of 55-MWe solar-fossil hybrid electric power plant at Crosbyton, Texas

    Science.gov (United States)

    1982-02-01

    This report presents the preliminary design and the construction cost for a 5 MWe Solar Hybrid Electric Energy Plant (SHEEP) to be built at Crosbyton, Texas. The plant has been designed to serve as a small size, commercially operable power plant which fully demonstrates the function, performance, and cost of this solar technology and integrated steam management concept. Good lifetime performance at minimum cost were the critical design objectives. The major solar components of this plant are ten 203 foot diameter stationary tilted quartersphere solar bowls. Each with a slender 58 foot solar receiver which tracks the solar focus produced by the bowl. At peak insolation the ten bowls will produce sufficient steam to generate 5 MWe. This plant has only a few minutes of thermal storage capability. The plant has a fossil boiler (oil or gas fired) which is integrated into the solar-turbine steam loop to provide supplemental steam for electric generation at night or during periods of low insolation.

  11. Design and simulation of front end power converter for a microgrid with fuel cells and solar power sources

    Science.gov (United States)

    Jeevargi, Chetankumar; Lodhi, Anuj; Sateeshkumar, Allu; Elangovan, D.; Arunkumar, G.

    2017-11-01

    The need for Renewable Energy Sources (RES) is increasing due to increased demand for the supply of power and it is also environment friendly.In the recent few years, the cost of generation of the power from the RES has been decreased. This paper aims to design the front end power converter which is required for integrating the fuel cells and solar power sources to the micro grid. The simulation of the designed front end converter is carried out in the PSIM 9.1.1 software. The results show that the designed front end power converter is sufficient for integrating the micro grid with fuel cells and solar power sources.

  12. Control of Solar Power Plants Connected Grid with Simple Calculation Method on Residential Homes

    Science.gov (United States)

    Kananda, Kiki; Nazir, Refdinal

    2017-12-01

    One of the most compatible renewable energy in all regions to apply is solar energy. Solar power plants can be built connected to existing or stand-alone power grids. In assisting the residential electricity in which there is a power grid, then a small scale solar energy power plants is very appropriate. However, the general constraint of solar energy power plants is still low in terms of efficiency. Therefore, this study will explain how to control the power of solar power plants more optimally, which is expected to reactive power to zero to raise efficiency. This is a continuation of previous research using Newton Rapshon control method. In this study we introduce a simple method by using ordinary mathematical calculations of solar-related equations. In this model, 10 PV modules type of ND T060M1 with a 60 Wp capacity are used. The calculations performed using MATLAB Simulink provide excellent value. For PCC voltage values obtained a stable quantity of approximately 220 V. At a maximum irradiation condition of 1000 W / m2, the reactive power value of Q solar generating system maximum 20.48 Var and maximum active power of 417.5 W. In the condition of lower irradiation, value of reactive power Q almost close to zero 0.77Var. This simple mathematical method can provide excellent quality control power values.

  13. Retrofitting a Geothermal Plant with Solar and Storage to Increase Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Guangdong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McTigue, Joshua Dominic P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Turchi, Craig S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Castro, Jose [Coso Operating Co.; Mungas, Greg [Hyperlight Energy; Kramer, Nick [Hyperlight Energy; King, John [Hyperlight Energy

    2017-10-04

    Solar hybridization using concentrating solar power (CSP) can be an effective approach to augment the power generation and power cycle efficiency of a geothermal power plant with a declining resource. Thermal storage can further increase the dispatchability of a geothermal/solar hybrid system, which is particularly valued for a national grid with high renewable penetration. In this paper, a hybrid plant design with thermal storage is proposed based on the requirements of the Coso geothermal field in China Lake, California. The objective is to increase the power production by 4 MWe. In this system, a portion of the injection brine is recirculated through a heat exchanger with the solar heat transfer fluid, before being mixed with the production well brine. In the solar heating loop the brine should be heated to at least 155 degrees C to increase the net power. The solar field and storage were sized based on solar data for China Lake. Thermal storage is used to store excess power at the high-solar-irradiation hours and generate additional power during the evenings. The solar field size, the type and capacity of thermal storage and the operating temperatures are critical factors in determining the most economic hybrid system. Further investigations are required to optimize the hybrid system and evaluate its economic feasibility.

  14. Comparison of sensorless dimming control based on building modeling and solar power generation

    International Nuclear Information System (INIS)

    Lee, Naeun; Kim, Jonghun; Jang, Cheolyong; Sung, Yoondong; Jeong, Hakgeun

    2015-01-01

    Artificial lighting in office buildings accounts for about 30% of the total building energy consumption. Lighting energy is important to reduce building energy consumption since artificial lighting typically has a relatively large energy conversion factor. Therefore, previous studies have proposed a dimming control using daylight. When applied dimming control, method based on building modeling does not need illuminance sensors. Thus, it can be applied to existing buildings that do not have illuminance sensors. However, this method does not accurately reflect real-time weather conditions. On the other hand, solar power generation from a PV (photovoltaic) panel reflects real-time weather conditions. The PV panel as the sensor improves the accuracy of dimming control by reflecting disturbance. Therefore, we compared and analyzed two types of sensorless dimming controls: those based on the building modeling and those that based on solar power generation using PV panels. In terms of energy savings, we found that a dimming control based on building modeling is more effective than that based on solar power generation by about 6%. However, dimming control based on solar power generation minimizes the inconvenience to occupants and can also react to changes in solar radiation entering the building caused by dirty window. - Highlights: • We conducted sensorless dimming control based on solar power generation. • Dimming controls using building modeling and solar power generation were compared. • The real time weather conditions can be considered by using solar power generation. • Dimming control using solar power generation minimizes inconvenience to occupants

  15. The effect of pole's height on the output performance of solar power ...

    African Journals Online (AJOL)

    Solar energy is a renewable (non-conventional) source of energy supply that has been used as a reliable energy source in view of its economic importance and its wide range of applications. In this study the effect of pole's height on the output performance of solar power system has been investigated. A solar panel of 45 ...

  16. Investigating Pulsed Discharge Polarity Employing Solid-State Pulsed Power Electronics

    DEFF Research Database (Denmark)

    Davari, Pooya; Zare, Firuz; Blaabjerg, Frede

    2015-01-01

    , the influence of electric field distribution is analyzed using Finite Element simulations for the employed geometries and mediums. The experimental and simulation results have verified the important role of the applied voltage polarity, employed geometry and medium of the system on plasma generation.......Power electronics technique has become a key technology in solid-state pulsed power supplies. Since pulsed power applications have been matured and found its way into many industrial applications, moving toward energy efficiency is gaining much more interest. Therefore, finding an optimum operation...... condition plays an important role in maintaining the desired performance. Investigating the system parameters contributed to the generated pulses is an effective way in improving the system performance further ahead. One of these parameters is discharge polarity which has received less attention...

  17. Shiraz solar power plant operation with steam engine

    International Nuclear Information System (INIS)

    Yaghoubi, M.; Azizian, K.

    2004-01-01

    The present industrial developments and daily growing need of energy, as well as economical and environmental problem caused by fossil fuels consumption, resulted certain constraint for the future demand of energy. During the past two decades great attention has been made to use renewable energy for different sectors. In this regard for the first time in Iran, design and construction of a 250 K W Solar power plant in Shiraz, Iran is being carried out and it will go to operation within next year. The important elements of this power plant is an oil cycle and a steam cycle, and several studies have been done about design and operation of this power plant, both for steady state and transient conditions. For the steam cycle, initially a steam turbine was chosen and due to certain limitation it has been replaced by a steam engine. The steam engine is able to produce electricity with hot or saturated vapor at different pressures and temperatures. In this article, the effects of installing a steam engine and changing its vapor inlet pressure and also the effects of sending hot or saturated vapor to generate electricity are studied. Various cycle performance and daily electricity production are determined. The effects of oil cycle temperature on the collector field efficiency, and daily, monthly and annual amount of electricity production is calculated. Results are compared with the steam cycle output when it contains a steam turbine. It is found that with a steam engine it is possible to produce more annual electricity for certain conditions

  18. Electric motorcycle charging station powered by solar energy

    Science.gov (United States)

    Siriwattanapong, Akarawat; Chantharasenawong, Chawin

    2018-01-01

    This research proposes a design and verification of an off-grid photovoltaic system (PVS) for electric motorcycle charging station to be located in King’s Mongkut’s University of Technology Thonburi, Bangkok, Thailand. The system is designed to work independently (off-grid) and it must be able to fully charge the batteries of a typical passenger electric motorcycle every evening. A 1,000W Toyotron electric motorcycle is chosen for this study. It carries five units of 12.8V 20Ah batteries in series; hence its maximum energy requirement per day is 1,200Wh. An assessment of solar irradiation data and the Generation Factor in Bangkok, Thailand suggests that the charging system consists of one 500W PV panel, an MPPT charge controller, 48V 150Ah battery, a 1,000W DC to AC inverter and other safety devices such as fuses and breakers. An experiment is conducted to verify the viability of the off-grid PVS charging station by collecting the total daily energy generation data in the raining season and winter. The data suggests that the designed off-grid solar power charging station for electric motorcycle is able to supply sufficient energy for daily charging requirements.

  19. Advanced sensible heat solar receiver for space power

    Science.gov (United States)

    Bennett, Timothy J.; Lacy, Dovie E.

    1988-01-01

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

  20. Construction and characterization of spherical Si solar cells combined with SiC electric power inverter

    Science.gov (United States)

    Oku, Takeo; Matsumoto, Taisuke; Hiramatsu, Kouichi; Yasuda, Masashi; Shimono, Akio; Takeda, Yoshikazu; Murozono, Mikio

    2015-02-01

    Spherical silicon (Si) photovoltaic solar cell systems combined with an electric power inverter using silicon carbide (SiC) field-effect transistor (FET) were constructed and characterized, which were compared with an ordinary Si-based converter. The SiC-FET devices were introduced in the direct current-alternating current (DC-AC) converter, which was connected with the solar panels. The spherical Si solar cells were used as the power sources, and the spherical Si panels are lighter and more flexible compared with the ordinary flat Si solar panels. Conversion efficiencies of the spherical Si solar cells were improved by using the SiC-FET.

  1. Corrosion Behavior Of Potential Structural Materials For Use In Nitrate Salts Based Solar Thermal Power Plants

    Science.gov (United States)

    Summers, Kodi

    The increasing global demand for electricity is straining current resources of fossil fuels and placing increased pressure on the environment. The implementation of alternative sources of energy is paramount to satisfying global electricity demand while reducing reliance on fossil fuels and lessen the impact on the environment. Concentrated solar power (CSP) plants have the ability to harness solar energy at an efficiency not yet achieved by other technologies designed to convert solar energy to electricity. The problem of intermittency in power production seen with other renewable technologies can be virtually eliminated with the use of molten salt as a heat transfer fluid in CSP plants. Commercial and economic success of CSP plants requires operating at maximum efficiency and capacity which requires high temperature and material reliability. This study investigates the corrosion behavior of structural alloys and electrochemical testing in molten nitrate salts at three temperatures common to CSP plants. Corrosion behavior was evaluated using gravimetric and inductively-coupled plasma optical emission spectroscopy (ICP-OES) analysis. Surface morphology was studied using scanning electron microscopy. Surface oxide structure and chemistry was characterized using X-ray diffraction, Raman spectroscopy, energy dispersive spectroscopy, and X-ray photoelectron spectroscopy. Electrochemical behavior of candidate structural alloys Alloy 4130, austenitic stainless steel 316, and super-austenitic Incoloy 800H was evaluated using potentiodynamic polarization characteristics. It was observed that electrochemical evaluation of these candidate materials correlates well with the corrosion behavior observed from gravimetric and ICP-OES analysis. This study identifies that all three alloys exhibited acceptable corrosion in 300°C molten salt while elevated salt temperatures require the more corrosion resistant alloys, stainless steel 316 and 800H. Characterization of the sample

  2. Dish layouts analysis method for concentrative solar power plant.

    Science.gov (United States)

    Xu, Jinshan; Gan, Shaocong; Li, Song; Ruan, Zhongyuan; Chen, Shengyong; Wang, Yong; Gui, Changgui; Wan, Bin

    2016-01-01

    Designs leading to maximize the use of sun radiation of a given reflective area without increasing the expense on investment are important to solar power plants construction. We here provide a method that allows one to compute shade area at any given time as well as the total shading effect of a day. By establishing a local coordinate system with the origin at the apex of a parabolic dish and z -axis pointing to the sun, neighboring dishes only with [Formula: see text] would shade onto the dish when in tracking mode. This procedure reduces the required computational resources, simplifies the calculation and allows a quick search for the optimum layout by considering all aspects leading to optimized arrangement: aspect ratio, shifting and rotation. Computer simulations done with information on dish Stirling system as well as DNI data released from NREL, show that regular-spacing is not an optimal layout, shifting and rotating column by certain amount can bring more benefits.

  3. Recommendations for the market introduction of solar thermal power stations

    International Nuclear Information System (INIS)

    Trieb, F.; Nitsch, J.

    1998-01-01

    Until 2010, solar thermal power stations based on parabolic trough concentrating collectors can become a competitive option on the world's electricity market, if the market extension of this mature technology is supported by a concerted, long-term programme capable of bundling the forces of industry, finance, insurance and politics. Technical improvements based on the experience of over ten years of successful operation, series production and economies of scale will lead to a further cost reduction of 50% and to electricity costs of 0.06 - 0.04 US$/kWh for hybrid steam cycles and hybrid combined cycles, respectively. Until 2010, a capacity of 7 GW will be installed, avoiding 16 million tons of carbon dioxide per year. The programme comprises an investment of 16 billion US$ and requires external funding of 6%. (author)

  4. Solar salt pond potential site survey for electrical power generation

    Science.gov (United States)

    Hurick, M. G.

    1982-01-01

    A solar salt gradient pond acts as a passive heat sink or thermal battery in which energy can be recovered through the conversion of thermal energy into electrical energy. Here, a condensation of a larger report that focused on the identification of potential salt gradient pond sites in the United States using in-situ resources is presented. It is shown that there are at least 24 states that lie in a primary or secondary potential site category. Fourteen states are assigned as primary states and ten are assigned as secondary. The division is subjectively based on the severity of winter weather. The most promising states are those that lie in the southern half of the country. When the primary and secondary category states are combined with the other states that may be able to support a pond, a total of 38 states exhibit the possibility of supporting power generation sites of various size.

  5. Evaluating the enablers in solar power developments in the current scenario using fuzzy DEMATEL

    DEFF Research Database (Denmark)

    Luthra, Sunil; Govindan, Kannan; Kharb, Ravinder K.

    2016-01-01

    Determining solar power initiatives and developments for a country as large as India is difficult due to the involvement of different enablers. The decisions of these enablers will influence the formulation of strategies to encourage solar power development in India. The present research work...... critically analyzes Indian solar power developments to recognize and to evaluate key enablers that will encourage greater usage in Indias current scenario. A literature review that explores the Indian solar power sector is included, with a focus on need potential, and an examination of the key enablers...... is useful in dealing with the inherent ambiguity involved in studying interrelationships among the evaluated enablers. Research findings suggest that Initiatives taken at the state level (E7) and Power sector reforms (E12) have significant influence in adopting and encouraging Indias solar power development...

  6. Efficient Lightweight AC-AC Power Control for Solar UAV, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A highly efficient and lightweight dual bridge matrix power controller development is proposed that will provide high performance to a solar powered high altitude...

  7. Seasonal optimal mix of wind and solar power in a future, highly renewable Europe

    DEFF Research Database (Denmark)

    Heide, Dominik; Bremen, Lueder von; Greiner, Martin

    2010-01-01

    behaviors are able to counterbalance each other to a certain extent to follow the seasonal load curve. The best point of counterbalancing represents the seasonal optimal mix between wind and solar power generation. It leads to a pronounced minimum in required stored energy. For a 100% renewable Europe......The renewable power generation aggregated across Europe exhibits strong seasonal behaviors. Wind power generation is much stronger in winter than in summer. The opposite is true for solar power generation. In a future Europe with a very high share of renewable power generation those two opposite...... the seasonal optimal mix becomes 55% wind and 45% solar power generation. For less than 100% renewable scenarios the fraction of wind power generation increases and that of solar power generation decreases....

  8. Solar Photovoltaic Applications Seminar: Design, installation and operation of small, stand-alone photovoltaic power systems

    Science.gov (United States)

    1980-07-01

    An introduction to photoconductivity, semiconductors, and solar photovoltaic cells is included along with a demonstration of specific applications and application identification. Small solar cell power system design engineering is discussed. Solar PV power system applications involve classical direct electrical energy conversion and electric power system analysis and synthesis. Presentations and examples involve a variety of disciplines including structural analysis, electric power and load analysis, reliability, sizing and optimization; and, installation, operation and maintenance. Four specific system designs are demonstrated: water pumping; domestic uses; navigational and aircraft aids; and telecommunications. All of the applications discussed are for small power requirement (under 2 kilowatts), stand alone systems to be used in remote locations.

  9. Power Spectra, Power Law Exponents, and Anisotropy of Solar Wind Turbulence at Small Scales

    Science.gov (United States)

    Podesta, J. J.; Roberts, D. A.; Goldstein, M. L.

    2006-01-01

    The Wind spacecraft provides simultaneous solar wind velocity and magnetic field measurements with 3- second time resolution, roughly an order of magnitude faster than previous measurements, enabling the small scale features of solar wind turbulence to be studied in unprecedented detail. Almost the entire inertial range can now be explored (the inertial range extends from approximately 1 to 10(exp 3) seconds in the spacecraft frame) although the dissipation range of the velocity fluctuations is still out of reach. Improved measurements of solar wind turbulence spectra at 1 AU in the ecliptic plane are presented including spectra of the energy and cross-helicity, the magnetic and kinetic energies, the Alfven ratio, the normalized cross-helicity, and the Elsasser ratio. Some recent observations and theoretical challenges are discussed including the observation that the velocity and magnetic field spectra often show different power law exponents with values close to 3/2 and 5/3, respectively; the energy (kinetic plus magnetic) and cross-helicity often have approximately equal power law exponents with values intermediate between 3/2 and 5/3; and the Alfven ratio, the ratio of the kinetic to magnetic energy spectra, is often a slowly increasing function of frequency increasing from around 0.4 to 1 for frequencies in the inertial range. Differences between high- and low-speed wind are also discussed. Comparisons with phenomenological turbulence theories show that important aspects of the physics are yet unexplained.

  10. Urban solar irradiance and power prediction from nearby stations

    Directory of Open Access Journals (Sweden)

    Zihao Chen

    2017-06-01

    Full Text Available With the proliferation of small-scale solar PV installations, global horizontal irradiance (GHI and power predictions are becoming critical elements in the integration of PV generation into the grid. This paper considers short-term prediction, from 5 minutes to a few hours, based on historical meteorological measurement data from weather and power monitoring stations located in the Canberra (Australia region. The specific objective of this study is to produce skilful forecasts for (a generic target station using a minimal amount of observations from nearby stations. Thus, although a large number of weather and power variables are collected and used for developing and testing the prediction algorithms, the ultimate aim is to rely on a few predictors, mainly meteorologically based. This will allow the identification of critical instruments which would need to be installed in order to provide satisfactory PV power predictions while limiting capital and operating costs of monitoring. Relative mean absolute error (rMAE is used here to indicate prediction performance. Three statistical methods are tested for two different seasons, a winter and a summer. The relative importance of predictors and stations is assessed. A conversion from GHI to global irradiance on tilted surfaces, by means of simple geometry arguments and notion of irradiance components at a nearby site, is also introduced and tested. Finally, the prediction accuracy is categorised according to different clear-sky indices. Results show that when the clear-sky index exceeds 0.9 (near-to-cloudless conditions, the prediction performance is distinctly better than at lower clear sky indices, by at least 0.05 and 0.2 in terms of rMAE in summer and winter, respectively.

  11. Solar Power Ramp Events Detection Using an Optimized Swinging Door Algorithm: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Mingjian; Zhang, Jie; Florita, Anthony; Hodge, Bri-Mathias; Ke, Deping; Sun, Yuanzhang

    2015-08-07

    Solar power ramp events (SPREs) are those that significantly influence the integration of solar power on non-clear days and threaten the reliable and economic operation of power systems. Accurately extracting solar power ramps becomes more important with increasing levels of solar power penetrations in power systems. In this paper, we develop an optimized swinging door algorithm (OpSDA) to detection. First, the swinging door algorithm (SDA) is utilized to segregate measured solar power generation into consecutive segments in a piecewise linear fashion. Then we use a dynamic programming approach to combine adjacent segments into significant ramps when the decision thresholds are met. In addition, the expected SPREs occurring in clear-sky solar power conditions are removed. Measured solar power data from Tucson Electric Power is used to assess the performance of the proposed methodology. OpSDA is compared to two other ramp detection methods: the SDA and the L1-Ramp Detect with Sliding Window (L1-SW) method. The statistical results show the validity and effectiveness of the proposed method. OpSDA can significantly improve the performance of the SDA, and it can perform as well as or better than L1-SW with substantially less computation time.

  12. The polarization modulators based on liquid crystal variable retarders for the PHI and METIS instruments for the solar orbiter mission

    Science.gov (United States)

    Alvarez-Herrero, A.; García Parejo, P.; Laguna, H.; Villanueva, J.; Barandiarán, J.; Bastide, L.; Reina, M.; Royo, M.

    2017-11-01

    A technical development activity was carried out from 2009 to 2011 under ESA supervision to validate the Liquid Crystal Variable Retarders (LCVRs) as polarization modulators for the Solar Orbiter mission. After this, the technology achieved the Technology Readiness Level 5 (TRL5) corresponding to "Component Validation in Relevant Environment". Afterwards, additional tests and characterizations were performed in order to select the final specifications of the LCVRs cells to optimize their performances under the mission environmental conditions. The LCVRs will be used to measure the complete Stokes vector of the incoming light in PHI (The Polarimetric and Helioseismic Imager for Solar Orbiter) and the linear polarization in the case of METIS (Multi Element Telescope for Imaging and Spectroscopy). PHI is an imaging spectro-polarimeter that will acquire high resolution solar magnetograms. On the other hand, METIS is a solar coronagraph that will analyze the linear polarization for observations of the visible-light K-corona. The polarization modulators are described in this work including the optical, mechanical, thermal and electrical aspects. Both modulators will consist of two identical LCVRs with a relative azimuth orientation of 45° for PHI and parallel for the METIS modulator. In the first case, the configuration allows the analysis of the full Stockes vector with maximum polarimetric efficiencies. In the second setup, wide acceptance angles (stress produced by the mounts to the cells, but taking into account the vibration environment due to the launch loads that the device shall withstand. Additionally, the optical clear aperture has been maximized and the design avoids breaks due to thermo-elastic deformations produced during the thermal cycling. Finally, the electrical cables and connections have been designed to obtain a very compact, modular and robust device.

  13. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    2011-01-01

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption...

  14. Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

    DEFF Research Database (Denmark)

    Heide, Dominik; Greiner, Martin; von Bremen, Lüder

    The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption...

  15. Developing a hybrid solar/wind powered irrigation system for crops in the Great Plains

    Science.gov (United States)

    Some small scale irrigation systems (powered by wind or solar do not require subsidies, but this paper discusses ways to achieve an economical renewable energy powered center pivot irrigation system for crops in the Great Plains. By adding a solar-photovoltaic (PV) array together with a wind...

  16. Solar PV powered mobile cellular base station: Models and use cases in South Africa

    CSIR Research Space (South Africa)

    Aderemi, BA

    2017-09-01

    Full Text Available cells. To this end, solar PV powered base stations have become important integration into a mobile cellular network. Thus, this article exploits the use of solar PV powered mobile cellular base station systems in South Africa. It was also found through...

  17. Combined cycle solar central receiver hybrid power system study. Volume III. Appendices. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-11-01

    A design study for a 100 MW gas turbine/steam turbine combined cycle solar/fossil-fuel hybrid power plant is presented. This volume contains the appendices: (a) preconceptual design data; (b) market potential analysis methodology; (c) parametric analysis methodology; (d) EPGS systems description; (e) commercial-scale solar hybrid power system assessment; and (f) conceptual design data lists. (WHK)

  18. 77 FR 39736 - Certain Integrated Solar Power Systems and Components Thereof; Notice of Termination of the...

    Science.gov (United States)

    2012-07-05

    ... certain integrated solar power systems and components thereof by reason of infringement of certain claims... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-811] Certain Integrated Solar Power Systems and Components Thereof; Notice of Termination of the Investigation Based on Settlement AGENCY: U.S...

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

    Science.gov (United States)

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

    1983-01-01

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

  20. Productivity Enhancement of Solar Still with PV Powered Heating Coil and Chamber Step-Wise Basin

    Directory of Open Access Journals (Sweden)

    Salah Abdallah

    2018-03-01

    Full Text Available There is a strong need to improve the productivity of single slope solar still. PV generator powered electrical heater and chamber step-wise design were introduced to the conventional solar still. An experimental study was performed to investigate the effect of adding the above mentioned modifications on the output parameters of the modified solar still. The inclusion of PV-powered heating coil and chamber step-wise design enhanced the productivity of distiller by up to 1098%.

  1. Possible effect of extreme solar energetic particle event of 20 January 2005 on polar stratospheric aerosols: direct observational evidence

    Science.gov (United States)

    Mironova, I. A.; Usoskin, I. G.; Kovaltsov, G. A.; Petelina, S. V.

    2012-01-01

    Energetic cosmic rays are the main source of ionization of the low-middle atmosphere, leading to associated changes in atmospheric properties. Via the hypothetical influence of ionization on aerosol growth and facilitated formation of clouds, this may be an important indirect link relating solar variability to climate. This effect is highly debated, however, since the proposed theoretical mechanisms still remain illusive and qualitative, and observational evidence is inconclusive and controversial. Therefore, important questions regarding the existence and magnitude of the effect, and particularly the fraction of aerosol particles that can form and grow, are still open. Here we present empirical evidence of the possible effect caused by cosmic rays upon polar stratospheric aerosols, based on a case study of an extreme solar energetic particle (SEP) event of 20 January 2005. Using aerosol data obtained over polar regions from different satellites with optical instruments that were operating during January 2005, such as the Stratospheric Aerosol and Gas Experiment III (SAGE III), and Optical Spectrograph and Infrared Imaging System (OSIRIS), we found a significant simultaneous change in aerosol properties in both the Southern and Northern Polar regions in temporal association with the SEP event. We speculate that ionization of the atmosphere, which was abnormally high in the lower stratosphere during the extreme SEP event, might have led to formation of new particles and/or growth of preexisting ultrafine particles in the polar stratospheric region. However, a detailed interpretation of the effect is left for subsequent studies. This is the first time high vertical resolution measurements have been used to discuss possible production of stratospheric aerosols under the influence of cosmic ray induced ionization. The observed effect is marginally detectable for the analyzed severe SEP event and can be undetectable for the majority of weak-moderate events. The present

  2. Downscaling Solar Power Output to 4-Seconds for Use in Integration Studies (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Hummon, M.; Weekley, A.; Searight, K.; Clark, K.

    2013-10-01

    High penetration renewable integration studies require solar power data with high spatial and temporal accuracy to quantify the impact of high frequency solar power ramps on the operation of the system. Our previous work concentrated on downscaling solar power from one hour to one minute by simulation. This method used clearness classifications to categorize temporal and spatial variability, and iterative methods to simulate intra-hour clearness variability. We determined that solar power ramp correlations between sites decrease with distance and the duration of the ramp, starting at around 0.6 for 30-minute ramps between sites that are less than 20 km apart. The sub-hour irradiance algorithm we developed has a noise floor that causes the correlations to approach ~0.005. Below one minute, the majority of the correlations of solar power ramps between sites less than 20 km apart are zero, and thus a new method to simulate intra-minute variability is needed. These intra-minute solar power ramps can be simulated using several methods, three of which we evaluate: a cubic spline fit to the one-minute solar power data; projection of the power spectral density toward the higher frequency domain; and average high frequency power spectral density from measured data. Each of these methods either under- or over-estimates the variability of intra-minute solar power ramps. We show that an optimized weighted linear sum of methods, dependent on the classification of temporal variability of the segment of one-minute solar power data, yields time series and ramp distributions similar to measured high-resolution solar irradiance data.

  3. Use of a Geothermal-Solar Hybrid Power Plant to Mitigate Declines in Geothermal Resource Productivity

    Energy Technology Data Exchange (ETDEWEB)

    Dan Wendt; Greg Mines

    2014-09-01

    Many, if not all, geothermal resources are subject to decreasing productivity manifested in the form of decreasing brine temperature, flow rate, or both during the life span of the associated power generation project. The impacts of resource productivity decline on power plant performance can be significant; a reduction in heat input to a power plant not only decreases the thermal energy available for conversion to electrical power, but also adversely impacts the power plant conversion efficiency. The reduction in power generation is directly correlated to a reduction in revenues from power sales. Further, projects with Power Purchase Agreement (PPA) contracts in place may be subject to significant economic penalties if power generation falls below the default level specified. A potential solution to restoring the performance of a power plant operating from a declining productivity geothermal resource involves the use of solar thermal energy to restore the thermal input to the geothermal power plant. There are numerous technical merits associated with a renewable geothermal-solar hybrid plant in which the two heat sources share a common power block. The geo-solar hybrid plant could provide a better match to typical electrical power demand profiles than a stand-alone geothermal plant. The hybrid plant could also eliminate the stand-alone concentrated solar power plant thermal storage requirement for operation during times of low or no solar insolation. This paper identifies hybrid plant configurations and economic conditions for which solar thermal retrofit of a geothermal power plant could improve project economics. The net present value of the concentrated solar thermal retrofit of an air-cooled binary geothermal plant is presented as functions of both solar collector array cost and electricity sales price.

  4. Modeling Small Scale Solar Powered ORC Unit for Standalone Application

    Directory of Open Access Journals (Sweden)

    Enrico Bocci

    2012-01-01

    Full Text Available When the electricity from the grid is not available, the generation of electricity in remote areas is an essential challenge to satisfy important needs. In many developing countries the power generation from Diesel engines is the applied technical solution. However the cost and supply of fuel make a strong dependency of the communities on the external support. Alternatives to fuel combustion can be found in photovoltaic generators, and, with suitable conditions, small wind turbines or microhydroplants. The aim of the paper is to simulate the power generation of a generating unit using the Rankine Cycle and using refrigerant R245fa as a working fluid. The generation unit has thermal solar panels as heat source and photovoltaic modules for the needs of the auxiliary items (pumps, electronics, etc.. The paper illustrates the modeling of the system using TRNSYS platform, highlighting standard and “ad hoc” developed components as well as the global system efficiency. In the future the results of the simulation will be compared with the data collected from the 3 kW prototype under construction in the Tuscia University in Italy.

  5. Contribution of Strong Discontinuities to the Power Spectrum of the Solar Wind

    International Nuclear Information System (INIS)

    Borovsky, Joseph E.

    2010-01-01

    Eight and a half years of magnetic field measurements (2 22 samples) from the ACE spacecraft in the solar wind at 1 A.U. are analyzed. Strong (large-rotation-angle) discontinuities in the solar wind are collected and measured. An artificial time series is created that preserves the timing and amplitudes of the discontinuities. The power spectral density of the discontinuity series is calculated and compared with the power spectral density of the solar-wind magnetic field. The strong discontinuities produce a power-law spectrum in the ''inertial subrange'' with a spectral index near the Kolmogorov -5/3 index. The discontinuity spectrum contains about half of the power of the full solar-wind magnetic field over this ''inertial subrange.'' Warnings are issued about the significant contribution of discontinuities to the spectrum of the solar wind, complicating interpretation of spectral power and spectral indices.

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

    DEFF Research Database (Denmark)

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

    2012-01-01

    services that are especially relevant for wind and solar power. These are mainly related to frequency, voltage control and restoration of the system. In addition, based on existing experience and wind integration studies, the paper analyses impacts that high amounts of wind/solar will have on different......With significantly increasing share of variable renewable power generation like wind and solar PV, the need in the power system for ancillary services supporting the network frequency, voltage, etc. changes. Turning this issue around, market opportunities will emerge for wind and solar PV...... technology to deliver such grid services. In the European power system, adequate market mechanisms need to be developed to ensure that there will be an efficient trading of these services. For that purpose a range of (economic) characteristics of wind (and solar) power as providers of grid services need...

  7. System and method for aligning heliostats of a solar power tower

    Science.gov (United States)

    Convery, Mark R.

    2013-01-01

    Disclosed is a solar power tower heliostat alignment system and method that includes a solar power tower with a focal area, a plurality of heliostats that each reflect sunlight towards the focal area of the solar power tower, an off-focal area location substantially close to the focal area of the solar power tower, a communication link between the off-focal area location and a misaligned heliostat, and a processor that interprets the communication between the off-focal area location and the misaligned heliostat to identify the misaligned heliostat from the plurality of heliostats and that determines a correction for the identified misaligned heliostat to realign the misaligned heliostat to reflect sunlight towards the focal area of the solar power tower.

  8. Comparison of candidate solar array maximum power utilization approaches. [for spacecraft propulsion

    Science.gov (United States)

    Costogue, E. N.; Lindena, S.

    1976-01-01

    A study was made of five potential approaches that can be utilized to detect the maximum power point of a solar array while sustaining operations at or near maximum power and without endangering stability or causing array voltage collapse. The approaches studied included: (1) dynamic impedance comparator, (2) reference array measurement, (3) onset of solar array voltage collapse detection, (4) parallel tracker, and (5) direct measurement. The study analyzed the feasibility and adaptability of these approaches to a future solar electric propulsion (SEP) mission, and, specifically, to a comet rendezvous mission. Such missions presented the most challenging requirements to a spacecraft power subsystem in terms of power management over large solar intensity ranges of 1.0 to 3.5 AU. The dynamic impedance approach was found to have the highest figure of merit, and the reference array approach followed closely behind. The results are applicable to terrestrial solar power systems as well as to other than SEP space missions.

  9. Contribution of strong discontinuities to the power spectrum of the solar wind.

    Science.gov (United States)

    Borovsky, Joseph E

    2010-09-10

    Eight and a half years of magnetic field measurements (2(22) samples) from the ACE spacecraft in the solar wind at 1 A.U. are analyzed. Strong (large-rotation-angle) discontinuities in the solar wind are collected and measured. An artificial time series is created that preserves the timing and amplitudes of the discontinuities. The power spectral density of the discontinuity series is calculated and compared with the power spectral density of the solar-wind magnetic field. The strong discontinuities produce a power-law spectrum in the "inertial subrange" with a spectral index near the Kolmogorov -5/3 index. The discontinuity spectrum contains about half of the power of the full solar-wind magnetic field over this "inertial subrange." Warnings are issued about the significant contribution of discontinuities to the spectrum of the solar wind, complicating interpretation of spectral power and spectral indices.

  10. Performance of double source boiler with coal-fired and solar power tower heat for supercritical power generating unit

    International Nuclear Information System (INIS)

    Zhang, Maolong; Du, Xiaoze; Pang, Liping; Xu, Chao; Yang, Lijun

    2016-01-01

    An approach of high-efficiency utilization of solar energy was proposed, by which the high concentrated heat received by the solar tower was integrated to the supercritical coal-fired boiler. Two schemes that solar energy was used to heat superheat steam or subcooled feed water were presented. The thermodynamic and heat transfer models were established. For a practical 660 MW supercritical power generating unit, the standard coal consumption of power generation could be decreased by more than 17 g/kWh by such double source boiler. The drawbacks of both schemes were found and then were amended by adding a flue gas bypass to the boiler. It also can be concluded that the maximum solar contribution of two schemes for the gross power generation are 6.11% and 4.90%, respectively. The solar power efficiency of the re-modified designs were demonstrated be superior to that of PS10. In terms of turbine efficiency, the comparisons with Solar Two plant having similar initial temperature found that the efficiency of Scheme I was 5.25% higher than that of Solar Two while the advantage of Scheme II was existing either. Additionally, in two schemes with flue bypass when the medium was extracted, the thermal efficiency of boiler could be improved as well. - Highlights: • High concentrated solar tower heat is integrated to the supercritical coal-fired boiler. • The double source boiler can use solar energy to heat superheat steam or subcooled feed water. • Power generating coal consumption can be reduced by more than 17 g/kWh by the double source boiler. • The solar contribution of double source boiler for the gross power generation can be as high as 6.11%.

  11. Analysis of polarization methods for elimination of power overshoot in microbial fuel cells

    KAUST Repository

    Watson, Valerie J.

    2011-01-01

    Polarization curves from microbial fuel cells (MFCs) often show an unexpectedly large drop in voltage with increased current densities, leading to a phenomenon in the power density curve referred to as "power overshoot". Linear sweep voltammetry (LSV, 1 mV s- 1) and variable external resistances (at fixed intervals of 20 min) over a single fed-batch cycle in an MFC both resulted in power overshoot in power density curves due to anode potentials. Increasing the anode enrichment time from 30 days to 100 days did not eliminate overshoot, suggesting that insufficient enrichment of the anode biofilm was not the primary cause. Running the reactor at a fixed resistance for a full fed-batch cycle (~ 1 to 2 days), however, completely eliminated the overshoot in the power density curve. These results show that long times at a fixed resistance are needed to stabilize current generation by bacteria in MFCs, and that even relatively slow LSV scan rates and long times between switching circuit loads during a fed-batch cycle may produce inaccurate polarization and power density results for these biological systems. © 2010 Elsevier B.V. All rights reserved.

  12. The influence of solar wind variability on magnetospheric ULF wave power

    International Nuclear Information System (INIS)

    Pokhotelov, D.; Rae, I.J.; Mann, I.R.

    2015-01-01

    Magnetospheric ultra-low frequency (ULF) oscillations in the Pc 4-5 frequency range play an important role in the dynamics of Earth's radiation belts, both by enhancing the radial diffusion through incoherent interactions and through the coherent drift-resonant interactions with trapped radiation belt electrons. The statistical distributions of magnetospheric ULF wave power are known to be strongly dependent on solar wind parameters such as solar wind speed and interplanetary magnetic field (IMF) orientation. Statistical characterisation of ULF wave power in the magnetosphere traditionally relies on average solar wind-IMF conditions over a specific time period. In this brief report, we perform an alternative characterisation of the solar wind influence on magnetospheric ULF wave activity through the characterisation of the solar wind driver by its variability using the standard deviation of solar wind parameters rather than a simple time average. We present a statistical study of nearly one solar cycle (1996-2004) of geosynchronous observations of magnetic ULF wave power and find that there is significant variation in ULF wave powers as a function of the dynamic properties of the solar wind. In particular, we find that the variability in IMF vector, rather than variabilities in other parameters (solar wind density, bulk velocity and ion temperature), plays the strongest role in controlling geosynchronous ULF power. We conclude that, although time-averaged bulk properties of the solar wind are a key factor in driving ULF powers in the magnetosphere, the solar wind variability can be an important contributor as well. This highlights the potential importance of including solar wind variability especially in studies of ULF wave dynamics in order to assess the efficiency of solar wind-magnetosphere coupling.

  13. Solar battery power supply: A reliable power supply system for nursing clinic in Australia`s remote areas

    Energy Technology Data Exchange (ETDEWEB)

    Zahedi, A. [Monash Univ., Caulfield (Australia). Div. of Electrical and Computer Systems Engineering

    1997-12-31

    Design and performance investigation of a new solar-battery system to power health clinics in Australia`s remote and isolated areas is a research project being conducted in the Department. The objective of this paper is to present the solar-battery system and to discuss the design factors of the system.

  14. A Low-Power and Low-Voltage Power Management Strategy for On-Chip Micro Solar Cells

    Directory of Open Access Journals (Sweden)

    Ismail Cevik

    2015-01-01

    Full Text Available Fundamental characteristics of on-chip micro solar cell (MSC structures were investigated in this study. Several MSC structures using different layers in three different CMOS processes were designed and fabricated. Effects of PN junction structure and process technology on solar cell performance were measured. Parameters for low-power and low-voltage implementation of power management strategy and boost converter based circuits utilizing fractional voltage maximum power point tracking (FVMPPT algorithm were determined. The FVMPPT algorithm works based on the fraction between the maximum power point operation voltage and the open circuit voltage of the solar cell structure. This ratio is typically between 0.72 and 0.78 for commercially available poly crystalline silicon solar cells that produce several watts of power under typical daylight illumination. Measurements showed that the fractional voltage ratio is much higher and fairly constant between 0.82 and 0.85 for on-chip mono crystalline silicon micro solar cell structures that produce micro watts of power. Mono crystalline silicon solar cell structures were observed to result in better power fill factor (PFF that is higher than 74% indicating a higher energy harvesting efficiency.

  15. An illustrative note on the system price effect of wind and solar power. The German case

    International Nuclear Information System (INIS)

    Jaegemann, Cosima

    2014-01-01

    Exposing wind and solar power to the market price signal allows for cost-efficient investment decisions, as it incentivizes investors to account for the marginal value (MV el ) of renewable energy technologies. As shown by Lamont (2008), the MV el of wind and solar power units depends on their penetration level. More specifically, the MV el of wind and solar power units is a function of the respective unit's capacity factor and the covariance between its generation profile and the system marginal costs. The latter component of the MV el (i.e., the covariance) is found to decline as the wind and solar power penetration increases, displacing dispatchable power plants with higher short-run marginal costs of power production and thus reducing the system marginal costs in all generation hours. This so called 'system price effect' is analyzed in more detail in this paper. The analysis complements the work Lamont (2008) in two regards. First of all, an alternative expression for the MV el of wind and solar power units is derived, which shows that the MV el of fluctuating renewable energy technologies depends not only on their own penetration level but also on a variety of other parameters that are specific to the electricity system. Second, based on historical wholesale prices and wind and solar power generation data for Germany, a numerical 'ceteris paribus' example for Germany is presented which illustrates that the system price effect is already highly relevant for both wind and solar power generation in Germany.

  16. Evaluating the Solar Slowly Varying Component at C-Band Using Dual- and Single-Polarization Weather Radars in Europe

    Directory of Open Access Journals (Sweden)

    M. Gabella

    2017-01-01

    Full Text Available Six C-band weather radars located in Europe (Finland, Netherlands, and Switzerland have been used to monitor the slowly varying solar emission, which is an oscillation with an amplitude of several decibels and a period of approximately 27 days. It is caused by the fact that the number of active regions that enhance the solar radio emission with respect to the quiet component, as seen from Earth, varies because of the Sun’s rotation about its axis. The analysis is based on solar signals contained in the polar volume data produced during the operational weather scan strategy. This paper presents hundreds of daily comparisons between radar estimates and the Sun’s reference signal, during the current active Sun period (year 2014. The Sun’s reference values are accurately measured by the Dominion Radio Astrophysical Observatory (DRAO at S-band and converted to C-band using a standard DRAO formula. Vertical and horizontal polarization receivers are able to capture the monthly oscillation of the solar microwave signal: the standard deviation of the log-transformed ratio between radars and the DRAO reference ranges from 0.26 to 0.4 dB. A larger coefficient (and a different value for the quiet Sun component in the standard formula improves the agreement.

  17. Eigenanalysis and Graph Theory Combined to Determine the Seasonal and Solar-Cycle Variations of Polar Magnetic Fields

    Science.gov (United States)

    Shore, R. M.; Freeman, M. P.; Gjerloev, J. W.

    2017-12-01

    We apply the meteorological analysis method of Empirical Orthogonal Functions (EOF) to ground magnetometer measurements, and subsequently use graph theory to classify the results. The EOF method is used to characterise and separate contributions to the variability of the Earth's external magnetic field (EMF) in the northern polar region. EOFs decompose the noisy EMF data into a small number of independent spatio-temporal basis functions, which collectively describe the majority of the magnetic field variance. We use these basis functions (computed monthly) to infill where data are missing, providing a self-consistent description of the EMF at 5-minute resolution spanning 1997-2009 (solar cycle 23). The EOF basis functions are calculated independently for each of the 144 months (i.e. 1997-2009) analysed. Since (by definition) the basis vectors are ranked by their contribution to the total variance, their rank will change from month to month. We use graph theory to find clusters of quantifiably-similar spatial basis functions, and thereby track similar patterns throughout the span of 144 months. We find that the discovered clusters can be associated with well-known individual Disturbance Polar (DP)-type equivalent current systems (e.g. DP2, DP1, DPY, NBZ), or with the motion of these systems. Via this method, we thus describe the varying behaviour of these current systems over solar cycle 23. We present their seasonal and solar cycle variations and examine the response of each current system to solar wind driving.

  18. Stochastic Short-term High-resolution Prediction of Solar Irradiance and Photovoltaic Power Output

    Energy Technology Data Exchange (ETDEWEB)

    Melin, Alexander M. [ORNL; Olama, Mohammed M. [ORNL; Dong, Jin [ORNL; Djouadi, Seddik M. [ORNL; Zhang, Yichen [University of Tennessee, Knoxville (UTK), Department of Electrical Engineering and Computer Science

    2017-09-01

    The increased penetration of solar photovoltaic (PV) energy sources into electric grids has increased the need for accurate modeling and prediction of solar irradiance and power production. Existing modeling and prediction techniques focus on long-term low-resolution prediction over minutes to years. This paper examines the stochastic modeling and short-term high-resolution prediction of solar irradiance and PV power output. We propose a stochastic state-space model to characterize the behaviors of solar irradiance and PV power output. This prediction model is suitable for the development of optimal power controllers for PV sources. A filter-based expectation-maximization and Kalman filtering mechanism is employed to estimate the parameters and states in the state-space model. The mechanism results in a finite dimensional filter which only uses the first and second order statistics. The structure of the scheme contributes to a direct prediction of the solar irradiance and PV power output without any linearization process or simplifying assumptions of the signal’s model. This enables the system to accurately predict small as well as large fluctuations of the solar signals. The mechanism is recursive allowing the solar irradiance and PV power to be predicted online from measurements. The mechanism is tested using solar irradiance and PV power measurement data collected locally in our lab.

  19. Temperature and Solar Radiation Effects on Photovoltaic Panel Power

    OpenAIRE

    Karafil, Akif; Ozbay, Harun; Kesler, Metin

    2016-01-01

    Solar energy is converted to electrical energy directly by semi-conductors materials used in Photovoltaic (PV) panels. Although, there has been great advancements in semi-conductor material technology in recent years panel efficiency is very lower. There are many factors affecting the panel efficiency such as tilt angle, shading, dust, solar radiation level, temperature and wiring losses. Among these factors, solar radiation level and temperature are more prominent. The solar radiation level ...

  20. Cost-benefit analysis of hybrid wind-solar power generation by ...

    African Journals Online (AJOL)

    HOMER power optimization software for evaluation of design and performance of both off-grid and gridconnected power systems has been applied for cost-benefit analysis of a wind-solar hybrid power generation system. Comparison was also made with the cost per kilowatt of grid power supply. The hybrid system had a ...

  1. Thermodynamic analyses of solar thermal gasification of coal for hybrid solar-fossil power and fuel production

    International Nuclear Information System (INIS)

    Ng, Yi Cheng; Lipiński, Wojciech

    2012-01-01

    Thermodynamic analyses are performed for solar thermal steam and dry gasification of coal. The selected types of coal are anthracite, bituminous, lignite and peat. Two model conversion paths are considered for each combination of the gasifying agent and the coal type: production of the synthesis gas with its subsequent use in a combined cycle power plant to generate power, and production of the synthesis gas with its subsequent use to produce gasoline via the Fischer–Tropsch synthesis. Replacement of a coal-fired 35% efficient Rankine cycle power plant and a combustion-based integrated gasification combined cycle power plant by a solar-based integrated gasification combined cycle power plant leads to the reduction in specific carbon dioxide emissions by at least 47% and 27%, respectively. Replacement of a conventional gasoline production process via coal gasification and a subsequent Fischer–Tropsch synthesis with gasoline production via solar thermal coal gasification with a subsequent Fischer–Tropsch synthesis leads to the reduction in specific carbon dioxide emissions by at least 39%. -- Highlights: ► Thermodynamic analyses for steam and dry gasification of coal are presented. ► Hybrid solar-fossil paths to power and fuels are compared to those using only combustion. ► Hybrid power production can reduce specific CO 2 emissions by more than 27%. ► Hybrid fuel production can reduce specific CO 2 emissions by more than 39%.

  2. Development of a thin film solar cell interconnect for the PowerSphere concept

    International Nuclear Information System (INIS)

    Simburger, Edward J.; Matsumoto, James H.; Giants, Thomas W.; Garcia, Alexander; Liu, Simon; Rawal, Suraj P.; Perry, Alan R.; Marshall, Craig H.; Lin, John K.; Scarborough, Stephen E.; Curtis, Henry B.; Kerslake, Thomas W.; Peterson, Todd T.

    2005-01-01

    Progressive development of microsatellite technologies has resulted in increased demand for lightweight electrical power subsystems including solar arrays. The use of thin film photovoltaics has been recognized as a key solution to meet the power needs. The lightweight cells can generate sufficient power and still meet critical mass requirements. Commercially available solar cells produced on lightweight substrates are being studied as an option to fulfill the power needs. The commercially available solar cells are relatively inexpensive and have a high payoff potential. Commercially available thin film solar cells are primarily being produced for terrestrial applications. The need to convert the solar cell from a terrestrial to a space compatible application is the primary challenge. Solar cell contacts, grids and interconnects need to be designed to be atomic oxygen resistant and withstand rapid thermal cycling environments. A mechanically robust solar cell interconnect is also required in order to withstand handling during fabrication and survive during launch. The need to produce the solar cell interconnects has been identified as a primary goal of the PowerSphere program and is the topic of this paper. Details of the trade study leading to the final design involving the solar cell wrap around contact, flex blanket, welding process, and frame will be presented at the conference

  3. Evaluation end-of-life power generation of a satellite solar array

    International Nuclear Information System (INIS)

    Taherbaneh, Mohsen; Ghafooifard, H.; Rezaie, A.H.; Rahimi, K.

    2011-01-01

    Research highlights: → We present detailed design description and necessary considerations for solar panels utilized in a specific space mission. → All sources of losses and degradation of the solar panels are fully taken into account. → We introduce a comprehensive novel approach to investigate the electrical behavior of the solar panels. → We use a simple model to calculate the operating temperature range of the solar panels. → We also calculate Mission End-of-Life electrone fluence using SPENVIS. -- Abstract: Knowing the power generated by of solar arrays in a space missions shall satisfy mission requirements; prediction of the power generated by a solar array used in a space mission is very important and necessary. In this research, a detailed design description and necessary considerations for solar panels utilized in a specific space mission is presented. All sources of losses and degradation of solar panels are fully taken into account. This research emphasizes on investigation, analysis and verification of a manufactured solar assembly for a satellite before launch. Solar panels' generated power should be estimated at the end of the mission. For this purpose, radiation values and temperature operating range are specified for the mission. Panels' temperature operating rate is determined through considering a simple model and different spins for the satellite. Mission end-of-life 1 MeV equivalent dose is calculated by SPENVIS suite software. Finally, a comprehensive novel approach is introduced to investigate the electrical behavior of the solar panels. This approach can be implemented in MATLAB environment to obtain output power characteristics of the solar panels for each specific mission. The results are in full accordance with the mission requirements either in beginning-of-life or end-of-life. Therefore, the power prediction of the designed solar array for the mentioned satellite completely satisfies its mission requirements.

  4. Influence of Solar and Lunar Tides on the Mesopause Region as Observed in Polar Mesosphere Summer Echoes Characteristics

    Science.gov (United States)

    Dalin, P.; Kirkwood, S.; Pertsev, N.; Perminov, V.

    2017-10-01

    Long-term observations of polar mesosphere summer echoes (PMSE) from 2002 to 2012 are investigated with the aim to statistically study the effects of solar thermal migrating and lunar gravitational tides on aerosol layers and their environment at altitudes 80-90 km. The solar and lunar tidal periodicities are clearly present in PMSE data. For the first time, both amplitudes and phases of solar and lunar tides are estimated using PMSE data from the ESRAD radar located at Esrange (Sweden). The diurnal, semidiurnal, and terdiurnal solar migrating tides show pronounced periodicities in the PMSE strength and wind velocity components. Lunar tides demonstrate clear oscillations in the PMSE strength and wind velocities as well. "canonical" lunar gravitational tides, corresponding to the lunar gravitational potential, produce rather large amplitudes and are comparable to the solar thermal tides, whereas "noncanonical" lunar oscillations have minor effects on PMSE layers, but are still statistically significant. The influence of diurnal/semidiurnal tides and monthly/semimonthly tidal components is studied separately. Our estimations of solar thermal and lunar tidal amplitudes are in good agreement with those of previous model and experimental studies. A new mechanism of quadratic demodulation of the solar semidiurnal and lunar semidiurnal tides is shown to be valid at the summer mesopause and can explain periodical PMSE oscillations due to the lunar synodic semimonthly tide with period of 14.77 days. Two harmonics with periods of 27.0 and 13.5 days supposedly representing the solar rotation cycle are also clearly present in PMSE data.

  5. Solar fed DC-DC single ended primary inductance converter for low power applications

    Science.gov (United States)

    Narendranath, K. V.; Viswanath, Y.; Babu, K. Suresh; Arunkumar, G.; Elangovan, D.

    2017-11-01

    This paper presents 34 to 36 volts. SEPIC converter for solar fed applications. Now days, there has been tremendous increase in the usage of solar energy and this solar energy is most valuable energy source available all around the world. The solar energy system require a Dc-Dc converter in order to modulate and govern the changing output of the panel. In this paper, a system comprising of Single Ended Primary Inductance Converter [SEPIC] integrated with solar panel is proposed. This paper proposes SEPIC power converter design that will secure high performance and cost efficiency while powering up a LAMP load. This power converter designed with low output ripple voltage, higher efficiency and less electrical pressure on the power switching elements. The simulation and prototype hardware results are presented in this paper.

  6. Prospects for investment in large-scale, grid-connected solar power in Africa

    DEFF Research Database (Denmark)

    Hansen, Ulrich Elmer; Nygaard, Ivan; Pedersen, Mathilde Brix

    Solar power in Africa is on its way to becoming a market-based commodity, thus escaping the niche for individual electricity supply that is mainly supported by international donor organisations. Significant reductions in the cost of photovoltaic (PV) panels and a 400 percent increase in oil prices......-scale investments in grid-connected solar power plants and local assembly facilities for PV panels, have exceeded even optimistic scenarios. Finally, therefore, there seem to be bright prospects for investment in large-scale grid-connected solar power in Africa....... since the 1990s have changed the competiveness of solar PV in all markets, ranging from individual households via institutions to mini-grids and grid-connected installations. In volume and investment, the market for large-scale grid-connected solar power plants is by far the most important...

  7. A Co-Powered Biomass and Concentrated Solar Power Rankine Cycle Concept for Small Size Combined Heat and Power Generation

    Directory of Open Access Journals (Sweden)

    Eileen Tortora

    2013-03-01

    Full Text Available The present work investigates the matching of an advanced small scale Combined Heat and Power (CHP Rankine cycle plant with end-user thermal and electric load. The power plant consists of a concentrated solar power field co-powered by a biomass furnace to produce steam in a Rankine cycle, with a CHP configuration. A hotel was selected as the end user due to its high thermal to electric consumption ratio. The power plant design and its operation were modelled and investigated by adopting transient simulations with an hourly distribution. The study of the load matching of the proposed renewable power technology and the final user has been carried out by comparing two different load tracking scenarios, i.e., the thermal and the electric demands. As a result, the power output follows fairly well the given load curves, supplying, on a selected winter day, about 50 GJ/d of thermal energy and the 6 GJ/d of electric energy, with reduced energy dumps when matching the load.

  8. RADIATIVE TRANSFER MODELING OF THE ENIGMATIC SCATTERING POLARIZATION IN THE SOLAR Na i D{sub 1} LINE

    Energy Technology Data Exchange (ETDEWEB)

    Belluzzi, Luca [Istituto Ricerche Solari Locarno, CH-6605 Locarno Monti (Switzerland); Bueno, Javier Trujillo [Instituto de Astrofísica de Canarias, E-38205 La Laguna, Tenerife (Spain); Degl’Innocenti, Egidio Landi [Dipartimento di Fisica e Astronomia, Università di Firenze, I-50125 Firenze (Italy)

    2015-12-01

    The modeling of the peculiar scattering polarization signals observed in some diagnostically important solar resonance lines requires the consideration of the detailed spectral structure of the incident radiation field as well as the possibility of ground level polarization, along with the atom's hyperfine structure and quantum interference between hyperfine F-levels pertaining either to the same fine structure J-level, or to different J-levels of the same term. Here we present a theoretical and numerical approach suitable for solving this complex non-LTE radiative transfer problem. This approach is based on the density-matrix metalevel theory (where each level is viewed as a continuous distribution of sublevels) and on accurate formal solvers of the transfer equations and efficient iterative methods. We show an application to the D-lines of Na i, with emphasis on the enigmatic D{sub 1} line, pointing out the observable signatures of the various physical mechanisms considered. We demonstrate that the linear polarization observed in the core of the D{sub 1} line may be explained by the effect that one gets when the detailed spectral structure of the anisotropic radiation responsible for the optical pumping is taken into account. This physical ingredient is capable of introducing significant scattering polarization in the core of the Na i D{sub 1} line without the need for ground-level polarization.

  9. Linkages from DOE's Solar Photovoltaic R&D to Commercial Renewable Power from Solar Energy

    Energy Technology Data Exchange (ETDEWEB)

    Ruegg, Rosalie [TIA Consulting Inc., Emerald Isle, NC (United States); Thomas, Patrick [1790 Analytics LLC., Haddonfield, NJ (United States)

    2011-04-01

    DOE's Solar Photovoltaic R&D Subprogram promotes the development of cost-effective systems for directly converting solar energy into electricity for residential, commercial, and industrial applications. This study was commissioned to assess the extent to which the knowledge outputs of R&D funded by the DOE Solar PV subprogram are linked to downstream developments in commercial renewable power. A second purpose was to identify spillovers of the resulting knowledge to other areas of application. A third purpose was to lend support to a parallel benefit-cost study by contributing evidence of attribution of benefits to DOE.

  10. Maximum Power Angle (MPA) Based Maximum Power Point Tracking (MPPT) Technique for Efficiency Optimization of Solar PV System

    OpenAIRE

    SHARMA, DINESH KUMAR; Purohit, Ghanshyam

    2016-01-01

    A novel maximum power angle (MPA) based maximum power point tracking (MPPT) technique is reported. In this technique, a graphical and mathematical approach based maximum power angle determination mechanism is adopted. On the I-V characteristic curve, the angle made from the intersection point of open circuit voltage (VOC) and short circuit current (ISC) with respect to the voltage (V) axis to the point of maximum power (MPP) is determined using the known parameters of the solar PV module. The...

  11. 1480 W Plts Solar Power Plant Architecture With Solar Tracker For Controlling Microcontroller-Based Solar Panel In Tigaraja Village Sub-District Of Tigadolok Regency Of Simalungun

    Directory of Open Access Journals (Sweden)

    Robert Samosir

    2017-12-01

    Full Text Available Electrical energy has become a basic need for human being. In some remote areas however electricity is unreachable and poses a taboo subject and cannot be enjoyed by local people such as in Tigaraja Village Sub-District of Tigadolok Regency of Simalungun. The sun is a renewable energy that it is beneficial for power plant use. With PLTS solar energy can be changed into the sun through the solar panel. Battery Charge Regulator BCR operates stabilizing voltage from solar panel to battery. The battery will save electrical power to be distributed for household consumption. Since battery power has direct current however Inverter operates changing its direct current into alternating current. To optimize absorption of solar energy a servo motor is used to make solar panel moving by following the suns path. Arduino Uno as direct control of solar panel using solar sensor gives current for servo motor. Then the servo motor can move in reverse and forward. Therefore Household goods like water pumps lamps and televisions have been worked when people come home from their work.

  12. Optimisation of Storage for Concentrated Solar Power Plants

    Directory of Open Access Journals (Sweden)

    Luigi Cirocco

    2014-12-01

    Full Text Available The proliferation of non-scheduled generation from renewable electrical energy sources such concentrated solar power (CSP presents a need for enabling scheduled generation by incorporating energy storage; either via directly coupled Thermal Energy Storage (TES or Electrical Storage Systems (ESS distributed within the electrical network or grid. The challenges for 100% renewable energy generation are: to minimise capitalisation cost and to maximise energy dispatch capacity. The aims of this review article are twofold: to review storage technologies and to survey the most appropriate optimisation techniques to determine optimal operation and size of storage of a system to operate in the Australian National Energy Market (NEM. Storage technologies are reviewed to establish indicative characterisations of energy density, conversion efficiency, charge/discharge rates and costings. A partitioning of optimisation techniques based on methods most appropriate for various time scales is performed: from “whole of year”, seasonal, monthly, weekly and daily averaging to those best suited matching the NEM bid timing of five minute dispatch bidding, averaged on the half hour as the trading settlement spot price. Finally, a selection of the most promising research directions and methods to determine the optimal operation and sizing of storage for renewables in the grid is presented.

  13. Jülich solar power tower - system behavior during downtime

    Science.gov (United States)

    Baumann, Torsten; Göhring, Felix; Stadler, Hannes; Doerbeck, Till

    2017-06-01

    At the Jülich Solar Power Tower, two new shut-off dampers have been installed in the hot air piping system in order to reduce thermal losses during downtime of the plant. The thermodynamic behavior of the thermal energy storage and the steam boiler has been investigated with respect to heat losses after shut-down of the plant. Also, the change of temperature and the pressure drop at both shut-off dampers during downtime has been analyzed. Results show that for the storage, a reduction of thermal losses can be achieved by closing the damper overnight. Regarding the steam boiler, no improvements on heat losses were observed. If only two of the four storage chambers have been charged during operation, heat transfer between the chambers is observed after shut-down. It is concluded that natural convection is not the main source of thermal overnight losses, however, it can be lowered thanks to the dampers. Heat conduction and convectional heat transfer at the surfaces also contribute to the decrease of thermal energy, which can be lowered by thicker insulation layers in the future.

  14. The New Solar System: China’s Evolving Solar Industry and Its Implications for Competitive Solar Power in the United States and the World

    Energy Technology Data Exchange (ETDEWEB)

    Ball, Jeffrey [Stanford Univ., CA (United States); Reicher, Dan [Stanford Univ., CA (United States); Sun, Xiaojing [Stanford Univ., CA (United States); Pollock, Caitlin [Stanford Univ., CA (United States)

    2017-03-08

    Solar power is undergoing a revolution. Over the past decade, an energy source as old as the planet and theoretically all but limitless has plummeted in cost and begun in some places to be harnessed in large volume. This dynamic is disrupting the modern energy system and, as energy disruptions always do, rattling the geopolitical order. In the process, the industry that produces the equipment to convert sunlight into electricity is simultaneously reeling, consolidating, and surging. These twin transformations—one of the global energy system, one of the global solar industry—carry profound implications for national economies and for the planet. At the center of both transformations sits China. The New Solar System illuminates key and little- understood changes that are remaking the solar enterprise—in China and thus in the world. Based on this analysis, it recommends changes in U.S. solar policy—particularly timely with a new U.S. administration and Congress—that would put solar power on a more economically sensible path toward environmentally significant growth. The New Solar System does not seek to enable any country to beat another in the global solar industry. It seeks instead to help all countries find their most effective places. By better understanding and playing to their comparative strengths in the solar business, countries would achieve two key objectives. They would reduce the cost for the world of scaling up solar power. And they would be better positioned to fashion policies that maximized the long-term benefit to their own economies from solar’s global growth.

  15. Costs of solar and wind power variability for reducing CO2 emissions.

    Science.gov (United States)

    Lueken, Colleen; Cohen, Gilbert E; Apt, Jay

    2012-09-04

    We compare the power output from a year of electricity generation data from one solar thermal plant, two solar photovoltaic (PV) arrays, and twenty Electric Reliability Council of Texas (ERCOT) wind farms. The analysis shows that solar PV electricity generation is approximately one hundred times more variable at frequencies on the order of 10(-3) Hz than solar thermal electricity generation, and the variability of wind generation lies between that of solar PV and solar thermal. We calculate the cost of variability of the different solar power sources and wind by using the costs of ancillary services and the energy required to compensate for its variability and intermittency, and the cost of variability per unit of displaced CO(2) emissions. We show the costs of variability are highly dependent on both technology type and capacity factor. California emissions data were used to calculate the cost of variability per unit of displaced CO(2) emissions. Variability cost is greatest for solar PV generation at $8-11 per MWh. The cost of variability for solar thermal generation is $5 per MWh, while that of wind generation in ERCOT was found to be on average $4 per MWh. Variability adds ~$15/tonne CO(2) to the cost of abatement for solar thermal power, $25 for wind, and $33-$40 for PV.

  16. Energy Supply Characteristics of a Combined Solar Cell and Diesel Engine System with a Prediction Algorithm for Solar Power Generation

    Science.gov (United States)

    El-Sayed, Abeer Galal; Obara, Shin'ya

    The production of electricity from the solar cells continues to attract interest as a power source for distributed energy generation. It is important to be able to estimate solar cell power to optimize system energy management. This paper proposes a prediction algorithm based on a neural network (NN) to predict the electricity production from a solar cell. The operation plan for a combined solar cell and diesel engine generator system is examined using the NN prediction algorithm. Two systems are examined in this paper: one with and one without a power storage facility. Comparisons are presented of the results from the two systems with respect to the actual calculations of output power and the predicted electricity production from the solar cell. The exhaust heat from the engine is used to supply the heat demand. A back-up boiler is operated when the engine exhaust heat is insufficient to meet the heat demand. Electricity and heat are supplied to the demand side from the proposed systems, and no external sources are used. When the NN production-of-electricity prediction was introduced, the engine generator operating time was reduced by 12.5% in December and 16.7% for March and September. Moreover, an operation plan for the combined system exhaust heat is proposed, and the heat output characteristics of the back-up boiler are characterized.

  17. Improvement of RF Wireless Power Transmission Using a Circularly Polarized Retrodirective Antenna Array with EBG Structures

    Directory of Open Access Journals (Sweden)

    Son Trinh-Van

    2018-02-01

    Full Text Available This paper presents the performance improvement of a circularly polarized (CP retrodirective array (RDA through the suppression of mutual coupling effects. The RDA is designed based on CP Koch-shaped patch antenna elements with an inter-element spacing as small as 0.4 λ for a compact size ( λ is the wavelength in free space at the designed frequency of 5.2 GHz. Electromagnetic band gap (EBG structures are applied to reduce the mutual coupling between the antenna elements, thus improving the circular polarization characteristic of the RDA. Two CP RDAs with EBGs, in the case 5 × 5 and 10 × 10 arrays, are used as wireless power transmitters to transmit a total power of 50 W. A receiver is located at a distance of 1 m away from the transmitter to harvest the transmitted power. At the broadside direction, the simulated results demonstrate that the received powers are improved by approximately 11.32% and 12.45% when using the 5 × 5 and 10 × 10 CP RDAs with the EBGs, respectively, as the transmitters.

  18. Integrating Solar Power onto the Electric Grid - Bridging the Gap between Atmospheric Science, Engineering and Economics

    Science.gov (United States)

    Ghonima, M. S.; Yang, H.; Zhong, X.; Ozge, B.; Sahu, D. K.; Kim, C. K.; Babacan, O.; Hanna, R.; Kurtz, B.; Mejia, F. A.; Nguyen, A.; Urquhart, B.; Chow, C. W.; Mathiesen, P.; Bosch, J.; Wang, G.

    2015-12-01

    One of the main obstacles to high penetrations of solar power is the variable nature of solar power generation. To mitigate variability, grid operators have to schedule additional reliability resources, at considerable expense, to ensure that load requirements are met by generation. Thus despite the cost of solar PV decreasing, the cost of integrating solar power will increase as penetration of solar resources onto the electric grid increases. There are three principal tools currently available to mitigate variability impacts: (i) flexible generation, (ii) storage, either virtual (demand response) or physical devices and (iii) solar forecasting. Storage devices are a powerful tool capable of ensuring smooth power output from renewable resources. However, the high cost of storage is prohibitive and markets are still being designed to leverage their full potential and mitigate their limitation (e.g. empty storage). Solar forecasting provides valuable information on the daily net load profile and upcoming ramps (increasing or decreasing solar power output) thereby providing the grid advance warning to schedule ancillary generation more accurately, or curtail solar power output. In order to develop solar forecasting as a tool that can be utilized by the grid operators we identified two focus areas: (i) develop solar forecast technology and improve solar forecast accuracy and (ii) develop forecasts that can be incorporated within existing grid planning and operation infrastructure. The first issue required atmospheric science and engineering research, while the second required detailed knowledge of energy markets, and power engineering. Motivated by this background we will emphasize area (i) in this talk and provide an overview of recent advancements in solar forecasting especially in two areas: (a) Numerical modeling tools for coastal stratocumulus to improve scheduling in the day-ahead California energy market. (b) Development of a sky imager to provide short term

  19. A study on electric power management for power producer-suppliers utilizing output of megawatt-solar power plants

    Directory of Open Access Journals (Sweden)

    Hirotaka Takano

    2016-01-01

    Full Text Available The growth in penetration of photovoltaic generation units (PVs has brought new power management ideas, which achieve more profitable operation, to Power Producer-Suppliers (PPSs. The expected profit for the PPSs will improve if they appropriately operate their controllable generators and sell the generated electricity to contracted customers and Power Exchanges together with the output of Megawatt-Solar Power Plants (MSPPs. Moreover, we can expect that the profitable cooperation between the PPSs and the MSPPs decreases difficulties in the supply-demand balancing operation for the main power grids. However, it is necessary that the PPSs treat the uncertainty in output prediction of PVs carefully. This is because there is a risk for them to pay a heavy imbalance penalty. This paper presents a problem framework and its solution to make the optimal power management plan for the PPSs in consideration with the electricity procurement from the MSPPs. The validity of the authors’ proposal is verified through numerical simulations and discussions of their results.

  20. Polar solar wind and interstellar wind properties from interplanetary Lyman-alpha radiation measurements

    Science.gov (United States)

    Witt, N.; Blum, P. W.; Ajello, J. M.

    1981-01-01

    The analysis of Mariner 10 observations of Lyman-alpha resonance radiation shows an increase of interplanetary neutral hydrogen densities above the solar poles. This increase is caused by a latitudinal variation of the solar wind velocity and/or flux. Using both the Mariner 10 results and other solar wind observations, the values of the solar wind flux and velocity with latitude are determined for several cases of interest. The latitudinal variation of interplanetary hydrogen gas, arising from the solar wind latitudinal variation, is shown to be most pronounced in the inner solar system. From this result it is shown that spacecraft Lyman-alpha observations are more sensitive to the latitudinal anisotropy for a spacecraft location in the inner solar system near the downwind axis.