Scenarios for solar thermal energy applications in Brazil

International Nuclear Information System (INIS)

Martins, F.R.; Abreu, S.L.; Pereira, E.B.

2012-01-01

The Solar and Wind Energy Resource Assessment (SWERA) database is used to prepare and discuss scenarios for solar thermal applications in Brazil. The paper discusses low temperature applications (small and large scale water heating) and solar power plants for electricity production (concentrated solar power plants and solar chimney plants) in Brazil. The results demonstrate the feasibility of large-scale application of solar energy for water heating and electricity generation in Brazil. Payback periods for water heating systems are typically below 4 years if they were used to replace residential electric showerheads in low-income families. Large-scale water heating systems also present high feasibility and many commercial companies are adopting this technology to reduce operational costs. The best sites to set up CSP plants are in the Brazilian semi-arid region where the annual energy achieves 2.2 MW h/m 2 and averages of daily solar irradiation are larger than 5.0 kW h/m 2 /day. The western area of Brazilian Northeastern region meets all technical requirements to exploit solar thermal energy for electricity generation based on solar chimney technology. Highlights: ► Scenarios for solar thermal applications are presented. ► Payback is typically below 4 years for small scale water heating systems. ► Large-scale water heating systems also present high feasibility. ► The Brazilian semi-arid region is the best sites for CSP and chimney tower plants.

Solar Thermal Energy Storage in a Photochromic Macrocycle.

Science.gov (United States)

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

2016-07-25

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

Advances in solar thermal energy in Uruguay

International Nuclear Information System (INIS)

Franco Noceto, P.

2012-01-01

This article is about the law 18585 which declared de solar thermal energy as national interest. This law establishes the obligation to incorporate solar heating systems in health care centers, hotels and sports clubs.

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

Science.gov (United States)

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

2013-01-22

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

Thermal solar energy. Collective domestic hot water installations

International Nuclear Information System (INIS)

Garnier, Cedric; Chauvet, Chrystele; Fourrier, Pascal

2016-01-01

This brochure, edited by ADEME, the French office for energy management and sustainable development, gives a basic outlook on the way to complete the installation of a collective domestic water solar heating system. After some recall of what is solar energy, the thermal solar technology and the energy savings it may induce, this document presents the main hydraulic configurations of a solar heating system with water storage, the dimensioning of a solar water heating system and its cost estimation, the installation and the commissioning of the system, the monitoring and maintenance operations

Solar thermal energy conversion to electrical power

International Nuclear Information System (INIS)

Trinh, Anh-Khoi; González, Ivan; Fournier, Luc; Pelletier, Rémi; Sandoval V, Juan C.; Lesage, Frédéric J.

2014-01-01

The conversion of solar energy to electricity currently relies primarily on the photovoltaic effect in which photon bombardment of photovoltaic cells drives an electromotive force within the material. Alternatively, recent studies have investigated the potential of converting solar radiation to electricity by way of the Seebeck effect in which charge carrier mobility is generated by an asymmetric thermal differential. The present study builds upon these latest advancements in the state-of-the-art of thermoelectric system management by combining solar evacuated tube technology with commercially available Bismuth Telluride semiconductor modules. The target heat source is solar radiation and the target heat sink is thermal convection into the ambient air relying on wind aided forced convection. These sources of energy are reproduced in a laboratory controlled environment in order to maintain a thermal dipole across a thermoelectric module. The apparatus is then tested in a natural environment. The novelty of the present work lies in a net thermoelectric power gain for ambient environment applications and an experimental validation of theoretical electrical characteristics relative to a varying electrical load. - Highlights: • Solar radiation maintains a thermal tension which drives an electromotive force. • Voltage, current and electric power are reported and discussed. • Theoretical optimal thermoelectric conversion predictions are presented. • Theory is validated with experimentally measured data

Application of nanomaterials in solar thermal energy storage

Science.gov (United States)

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

2018-06-01

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

Application of nanomaterials in solar thermal energy storage

Science.gov (United States)

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

2017-12-01

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

Myo-inositol based nano-PCM for solar thermal energy storage

International Nuclear Information System (INIS)

Singh, D.K.; Suresh, S.; Singh, H.; Rose, B.A.J.; Tassou, S.; Anantharaman, N.

2017-01-01

Highlights: • Properties of Myo-Inositol laden with Al_2O_3 and CuO nanoparticles was studied. • The melting point was found to increase for MI-A and decrease for MI-C. • MI interacted only physically on addition of NPs. • Mass changes were <3% after thermal cycling of MI-A and MI-C. • MI-A is more suited for thermal energy storage than MI-C. - Abstract: The thermo-physical behavior of Myo-Inositol (MI), (a sugar alcohol), was investigated as a potential material for developing more compact solar thermal energy storage systems than those currently available. This latent heat storage medium could be utilized for commercial and industrial applications using solar thermal energy storage in the temperature range of 160–260 °C, if its thermal performance was modified. The objective of this investigation was to determine via experimentation, if Al_2O_3 and CuO nanoparticles dispersed in pure MI for mixtures of 1, 2 and 3% (by weight) improved the thermal performance of MI for solar thermal energy systems. Nanoparticles only physically interacted with MI, and not chemically, even after 50 thermal cycles. The distribution of CuO nanoparticles in the nano-PCM was found to be more uniform than alumina nanoparticles. After cycling, nano-MIs studied here suffered a lower decrease in heat of fusion than pure MI, which makes nano-MIs more suitable for solar thermal storage applications at 160–260 °C. Between CuO and Al_2O_3 nanoparticles, latter was found to be more suitable for compact solar thermal energy storage owing to an increase in melting point observed.

estec2007 - 3rd European solar thermal energy conference. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-12-14

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

estec2007 - 3rd European solar thermal energy conference. Proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-12-14

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

Economic Evaluation of a Solar Charged Thermal Energy Store for Space Heating

OpenAIRE

Melo, Manuel

2013-01-01

A thermal energy store corrects the misalignment of heating demand in the winter relative to solar thermal energy gathered in the summer. This thesis reviews the viability of a solar charged hot water tank thermal energy store for a school at latitude 56.25N, longitude -120.85W

Semi-transparent solar energy thermal storage device

Science.gov (United States)

McClelland, John F.

1985-06-18

A visually transmitting solar energy absorbing thermal storage module includes a thermal storage liquid containment chamber defined by an interior solar absorber panel, an exterior transparent panel having a heat mirror surface substantially covering the exterior surface thereof and associated top, bottom and side walls, Evaporation of the thermal storage liquid is controlled by a low vapor pressure liquid layer that floats on and seals the top surface of the liquid. Porous filter plugs are placed in filler holes of the module. An algicide and a chelating compound are added to the liquid to control biological and chemical activity while retaining visual clarity. A plurality of modules may be supported in stacked relation by a support frame to form a thermal storage wall structure.

Solar thermal aircraft

Science.gov (United States)

Bennett, Charles L.

2007-09-18

A solar thermal powered aircraft powered by heat energy from the sun. A heat engine, such as a Stirling engine, is carried by the aircraft body for producing power for a propulsion mechanism, such as a propeller. The heat engine has a thermal battery in thermal contact with it so that heat is supplied from the thermal battery. 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.

Proceedings of the General Committee for solar thermal energy 2017

International Nuclear Information System (INIS)

Loyen, Richard; Gibert, Francois; Porcheyre, Edwige; Laplagne, Valerie; Lambertucci, Stefano; Hauser, Eva; Delmas, Pierre; Mozas, Kevin; Servier, Gerard; Girard, Jean-Paul; Haim, Philippe; Gendron, Marc; Haas, Benjamin; Leclech, Rodrigue; Eberhardt, Mathieu; Bettwy, Fabrice; Berthomieu, Nadine; Barais, Claire; Mingant, Sylvie; Daniel, Charles; GODIN, Olivier; PELe, Charles; Benabdelkarim, Mohamed; Brottier, Laetitia; Cholin, Xavier; Mugnier, Daniel; Marchal, David; Khebchache, Bouzid

2017-10-01

The contributions of this conference first proposed an overview of the status and perspectives of the solar thermal energy sector with a presentation of the present situation and perspectives for the French market, and an overview of situations and initiatives in neighbouring European countries. A second session addressed the possible new economical and marketing models able to face challenges of solar thermal energy in 2018 with focuses on heat kWh purchase, on supply portage through a global operator contract (design-realisation-exploitation-maintenance contracts or CREM contracts, energy performance contracts or CPE), and on issues related to building renovation (solar-gas synergy) and to new buildings (regulatory evolution, E+C label). The third session proposed examples of local good practices: development of solar thermal networks in Auvergne-Rhone-Alpes with the development of these networks and a support to commissioners, ADEME's support with patrimony-rehabilitation contracts, and the solar policy implemented by the Brest metropole. A technological focus was then proposed. It addressed communications about the SOCOL approach, concentration-based solar technology (technology, applications, realisations), and solar heating (assets in new and renovated buildings). Before a synthesis, two interventions addressed the production of solar electron and calories, and works performed on the increase of the solar coverage rate

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

Directory of Open Access Journals (Sweden)

Jorge M. Llamas

2017-08-01

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

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

Directory of Open Access Journals (Sweden)

Krstić-Furundžić Aleksandra

2009-01-01

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

From Molecular Electronics to Solar Thermal Energy Storage

DEFF Research Database (Denmark)

Olsen, Stine Tetzschner

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

Photovoltaic. Solar thermal. Solar thermal electricity

International Nuclear Information System (INIS)

2009-01-01

The year 2008 was excellent for solar energy in the European Union. The growth of the installed capacity for photovoltaic was +159% (it means +4747.018 MW) to reach 9689.952 MW and that for solar thermal was +51.5% (it means +3172.5 MW) to reach 19982.7 MW. Worldwide concentrated solar thermal capacity stood at 679 MW in 2009, while this figure may seem low, the sector has a promising future ahead of it. (A.C.)

Interreg IIIA SR - AT project SOLARSTRAT. Results of the interviews with experts on solar-thermal energy utilization. Possibilities of support to thermal-solar systems installation

International Nuclear Information System (INIS)

Ilias, I.

2005-01-01

In this presentation author presented the results of collecting of important data for solar-thermal market scenario modelling through interviews with Slovak stakeholders. Interviews with Slovak experts on thermal-solar energy utilisation represents important project activity in order to give a general review of current status of the market in target Bratislava region and to collect important data for next market analyses, which will be prepared by Austrian partner - IFAST. The results of face-to-face interviews and filled questionnaires can be generally presented as follows: - public attitude towards the renewable energy sources and solar energy utilisation is slowly getting better in Slovakia; - evaluating public awareness only 15% share of population is able to consider the possibilities of thermal-solar technologies; - expected increase of fossil fuels and energy prices will help to spread of thermal-solar systems through shorten the pay-back period of investment while prices of thermal-solar systems will increase only slightly; - also expected increase of political and economic public awareness about energy production and demand on thermal-solar systems will help to promote the further development of solar energy utilisation in Slovakia. Respondents were also evaluating the main barriers for better solar energy utilisation: (1) Weak public awareness, no systematic information campaign (examples from real life); (2) Missing support to installation for physical persons, no tax allowances; (3) High investment costs; (4) Unfriendly legislation. Other important barriers for better development of the sector were presented. E.g. assembling companies cannot afford effective promotion, only big producers are able to fund the marketing on their products, which are mainly expensive systems. Public is still considering solar systems as too expensive ('I can't afford it'). Renewable energy sources (RES) are often presented as the alternative to nuclear energy - this

Interreg IIIA SR - AT project SOLARSTRAT. Results of the interviews with experts on solar-thermal energy utilization. Possibilities of support to thermal-solar systems installation

International Nuclear Information System (INIS)

Ilias, I.

2005-01-01

In this presentation author presented the results of collecting of important data for solar-thermal market scenario modelling through interviews with Slovak stakeholders. Interviews with Slovak experts on thermal-solar energy utilisation represents important project activity in order to give a general review of current status of the market in target Bratislava region and to collect important data for next market analyses, which will be prepared by Austrian partner - IFAST. The results of face-to-face interviews and filled questionnaires can be generally presented as follows: - public attitude towards the renewable energy sources and solar energy utilisation is slowly getting better in Slovakia; - evaluating public awareness only 15% share of population is able to consider the possibilities of thermal-solar technologies; - expected increase of fossil fuels and energy prices will help to spread of thermal-solar systems through shorten the pay-back period of investment while prices of thermal-solar systems will increase only slightly; - also expected increase of political and economic public awareness about energy production and demand on thermal-solar systems will help to promote the further development of solar energy utilisation in Slovakia. Respondent were also evaluating the main barriers for better solar energy utilisation: (1) Weak public awareness, no systematic information campaign (examples from real life); (2) Missing support to installation for physical persons, no tax allowances; (3) High investment costs; (4) Unfriendly legislation Other important barriers for better development of the sector were presented. E.g. assembling companies cannot afford effective promotion, only big producers are able to fund the marketing on their products, which are mainly expensive systems. Public is still considering solar systems as too expensive ('I can't afford it'). Renewable energy sources (RES) are often presented as the alternative to nuclear energy - this argument

Survey of EPA facilities for solar thermal energy applications

Science.gov (United States)

Nelson, E. V.; Overly, P. T.; Bell, D. M.

1980-01-01

A study was done to assess the feasibility of applying solar thermal energy systems to EPA facilities. A survey was conducted to determine those EPA facilities where solar energy could best be used. These systems were optimized for each specific application and the system/facility combinations were ranked on the basis of greatest cost effectiveness.

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.

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.

Dynamic tuning of optical absorbers for accelerated solar-thermal energy storage.

Science.gov (United States)

Wang, Zhongyong; Tong, Zhen; Ye, Qinxian; Hu, Hang; Nie, Xiao; Yan, Chen; Shang, Wen; Song, Chengyi; Wu, Jianbo; Wang, Jun; Bao, Hua; Tao, Peng; Deng, Tao

2017-11-14

Currently, solar-thermal energy storage within phase-change materials relies on adding high thermal-conductivity fillers to improve the thermal-diffusion-based charging rate, which often leads to limited enhancement of charging speed and sacrificed energy storage capacity. Here we report the exploration of a magnetically enhanced photon-transport-based charging approach, which enables the dynamic tuning of the distribution of optical absorbers dispersed within phase-change materials, to simultaneously achieve fast charging rates, large phase-change enthalpy, and high solar-thermal energy conversion efficiency. Compared with conventional thermal charging, the optical charging strategy improves the charging rate by more than 270% and triples the amount of overall stored thermal energy. This superior performance results from the distinct step-by-step photon-transport charging mechanism and the increased latent heat storage through magnetic manipulation of the dynamic distribution of optical absorbers.

Solar thermal energy utilization: A bibliography with abstracts

Science.gov (United States)

1976-01-01

Bibliographic series, which is periodically updated, cites documents published since 1957 relating to practical thermal utilization of solar energy. Bibliography is indexed by author, corporate source, title, and keywords.

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

Science.gov (United States)

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

2014-05-01

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

Comprehensive assessment of the role and potential for solar thermal in future energy systems

DEFF Research Database (Denmark)

Hansen, Kenneth; Mathiesen, Brian Vad

2018-01-01

to the energy system configurations. Solar thermal benefits reduce when moving towards a high-renewable energy system as other renewable energy sources start competing with solar thermal on energy prices and energy system flexibility. The findings can be applied to a diversity of energy systems also beyond...

Operational Experience from Solar Thermal Energy Projects

Science.gov (United States)

Cameron, C. P.

1984-01-01

Over the past few years, Sandia National Laboratories were involved in the design, construction, and operation of a number of DOE-sponsored solar thermal energy systems. Among the systems currently in operation are several industrial process heat projects and the Modular Industrial Solar Retrofit qualification test systems, all of which use parabolic troughs, and the Shenandoah Total Energy Project, which uses parabolic dishes. Operational experience has provided insight to both desirable and undesirable features of the designs of these systems. Features of these systems which are also relevant to the design of parabolic concentrator thermal electric systems are discussed. Other design features discussed are system control functions which were found to be especially convenient or effective, such as local concentrator controls, rainwash controls, and system response to changing isolation. Drive systems are also discussed with particular emphasis of the need for reliability and the usefulness of a manual drive capability.

Solar thermal utilization--an overview

International Nuclear Information System (INIS)

Chen Deming; Xu Gang

2007-01-01

Solar energy is an ideal renewable energy source and its thermal utilization is one of its most important applications. We review the status of solar thermal utilization, including: (1) developed technologies which are already widely used all over the world, such as solar assisted water heaters, solar cookers, solar heated buildings and so on; (2) advanced technologies which are still in the development or laboratory stage and could have more innovative applications, including thermal power generation, refrigeration, hydrogen production, desalination, and chimneys; (3) major problems which need to be resolved for advanced utilizaiton of solar thermal energy. (authors)

Smart thermal grid with integration of distributed and centralized solar energy systems

International Nuclear Information System (INIS)

Yang, Libing; Entchev, Evgueniy; Rosato, Antonio; Sibilio, Sergio

2017-01-01

Smart thermal grids (STGs) are able to perform the same function as classical grids, but are developed in order to make better use of distributed, possibly intermittent, thermal energy resources and to provide the required energy when needed through efficient resources utilization and intelligent management. District heating (DH) plays a significant role in the implementation of future smart energy systems. To fulfil its role, DH technologies must be further developed to integrate renewable resources, create low-temperature networks, and consequently to make existing or new DH networks ready for integration into future STGs. Solar heating is a promising option for low-temperature DH systems. Thermal energy storage (TES) can make the availability of the energy supply match the demand. An integration of centralized seasonal and distributed short-term thermal storages would facilitate an efficient recovery of the solar energy. This study, through modelling and simulation, investigates the impacts of such integration on the overall performance of a community-level solar DH system. The performance analysis results show that the solar DH system with integration of distributed and centralized seasonal TESs improves system overall efficiency, and reduces DH network heat losses, primary energy consumption and greenhouse gas emissions, in comparison to the one without integration. - Highlights: • STG should be designed to store energy in the most efficient way at the most effective location. • Integration of centralized seasonal and distributed TESs in a solar DH system is proposed. • Performance of such integrated solar DH system is evaluated and compared to the one without. • The integration results in reduction of primary energy consumption and GHG emission. • The integration improves the overall efficiency of the total solar energy system.

Solar thermal - the new dynamics

International Nuclear Information System (INIS)

2017-01-01

This booklet is intended to engineering consultants and construction professionals and aims at showing them the real interest of solar thermal energy. It notably highlights the very high efficiency which can be reached, the high performance value compared to gas, the high rank of solar thermal energy in terms of profitability over a 20-year period, the fact that solar thermal energy is almost always the most economic solution for buildings and the less expensive in comparison with non renewable energies. It outlines that, as far as purchase is concerned, solar thermal energy is more than competitive, is also a leader as far as financing issues are concerned. It finally briefly describes how the SOCOL initiative can be a support at any step of a solar thermal project

Economic Dispatch for Power System Included Wind and Solar Thermal Energy

Directory of Open Access Journals (Sweden)

Saoussen BRINI

2009-07-01

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

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

Energy Technology Data Exchange (ETDEWEB)

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

2004-07-01

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

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

Energy Technology Data Exchange (ETDEWEB)

Segaser, C. L.

1978-08-01

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

Solar Air Heaters with Thermal Heat Storages

OpenAIRE

Saxena, Abhishek; Goel, Varun

2013-01-01

Solar energy can be converted into different forms of energy, either to thermal energy or to electrical energy. Solar energy is converted directly into electrical power by photovoltaic modules, while solar collector converts solar energy into thermal energy. Solar collector works by absorbing the direct solar radiation and converting it into thermal energy, which can be stored in the form of sensible heat or latent heat or a combination of sensible and latent heats. A theoretical study has be...

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

Science.gov (United States)

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

2016-09-05

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

The solarPACES strategy for the solar thermal breakthrough

International Nuclear Information System (INIS)

Burch, G.D.; Grasse, W.

1997-01-01

IEA(International Energy Agency)/SolarPACES(Solar Power and Chemical Energy systems)represents a world wide coalition for information sharing and collaboration on applications of concentrated solar energy. The current SolarPACES community has built up solar thermal system know-how over 15 years, is operating the three main solar test centres in the world. Its main activities are in the following four fields: solar thermal electric power systems, solar chemistry, solar technology and advanced applications and non-technical activities. The article presents the talk on the strategy of solarPACES given at the International Workshop on applied solar energy held in Tashkent(Uzbekistan) in June 1997. (A.A.D.)

Full-energy-chain analysis of greenhouse gas emissions for solar thermal electric power generation systems

International Nuclear Information System (INIS)

Norton, B.; Lawson, W.R.

1997-01-01

Technical attributes and environmental impacts of solar thermal options for centralized electricity generation are discussed. In particular, the full-energy-chain, including embodied energy and energy production, is considered in relation to greenhouse gas emission arising from solar thermal electricity generation. Central receiver, parabolic dish, parabolic trough and solar pond systems are considered. (author)

Solar Energy.

Science.gov (United States)

Eaton, William W.

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

Solar thermal barometer

International Nuclear Information System (INIS)

Anon.

2004-01-01

After the bad year of 2002, the european solar thermal market returned to double-digit growth rate in 2003: 22%. Nevertheless, the sector still has not recovered the growth rate it had in the early 2000 and European Commission targets are still far from being reached. This paper presents the thermal solar industry barometer. Data on the evolution of annually installed surfaces in the european union since 1993, the cumulated capacity of thermal collectors installed in the European Union, the estimation of the annual energy production associated to european solar thermal capacities and the main companies of the European Union thermal solar sector are presented and discussed. (A.L.B.)

Economic impact of latent heat thermal energy storage systems within direct steam generating solar thermal power plants with parabolic troughs

International Nuclear Information System (INIS)

Seitz, M.; Johnson, M.; Hübner, S.

2017-01-01

Highlights: • Integration of a latent heat thermal energy storage system into a solar direct steam generation power cycle. • Parametric study of solar field and storage size for determination of the optimal layout. • Evaluation of storage impact on the economic performance of the solar thermal power plant. • Economic comparison of new direct steam generation plant layout with state-of-the-art oil plant layout. - Abstract: One possible way to further reduce levelized costs of electricity of concentrated solar thermal energy is to directly use water/steam as the primary heat transfer fluid within a concentrated collector field. This so-called direct steam generation offers the opportunity of higher operating temperatures and better exergy efficiency. A technical challenge of the direct steam generation technology compared to oil-driven power cycles is a competitive storage technology for heat transfer fluids with a phase change. Latent heat thermal energy storages are suitable for storing heat at a constant temperature and can be used for direct steam generation power plants. The calculation of the economic impact of an economically optimized thermal energy storage system, based on a latent heat thermal energy storage system with phase change material, is the main focus of the presented work. To reach that goal, a thermal energy storage system for a direct steam generation power plant with parabolic troughs in the solar field was thermally designed to determine the boundary conditions. This paper discusses the economic impact of the designed thermal energy storage system based on the levelized costs of electricity results, provided via a wide parametric study. A state-of-the-art power cycle with a primary and a secondary heat transfer fluid and a two-tank thermal energy storage is used as a benchmark technology for electricity generation with solar thermal energy. The benchmark and direct steam generation systems are compared to each other, based respectively

Performance analysis of an integrated energy storage and energy upgrade thermochemical solid–gas sorption system for seasonal storage of solar thermal energy

International Nuclear Information System (INIS)

Li, Tingxian; Wang, Ruzhu; Kiplagat, Jeremiah K.; Kang, YongTae

2013-01-01

An innovative dual-mode thermochemical sorption energy storage method is proposed for seasonal storage of solar thermal energy with little heat losses. During the charging phase in summer, solar thermal energy is stored in form of chemical bonds resulting from thermochemical decomposition process, which enables the stored energy to be kept several months at ambient temperature. During the discharging phase in winter, the stored thermal energy is released in the form of chemical reaction heat resulting from thermochemical synthesis process. Thermodynamic analysis showed that the advanced dual-mode thermochemical sorption energy storage is an effective method for the long-term seasonal storage of solar energy. A coefficient of performance (COP h ) of 0.6 and energy density higher than 1000 kJ/kg of salt can be attained from the proposed system. During the discharging phase at low ambient temperatures, the stored thermal energy can be upgraded by use of a solid–gas thermochemical sorption heat transformer cycle. The proposed thermochemical sorption energy storage has distinct advantages over the conventional sensible heat and latent heat storage, such as higher energy storage density, little heat losses, integrated energy storage and energy upgrade, and thus it can contribute to improve the seasonal utilization of solar thermal energy. - Highlights: ► A dual-mode solid thermochemical sorption is proposed for seasonal solar thermal energy storage. ► Energy upgrade techniques into the energy storage system are integrated. ► Performance of the proposed seasonal energy storage system is evaluated. ► Energy density and COP h from the proposed system are as high as 1043 kJ/kg of salt and 0.60, respectively

Influence of nanomaterials on properties of latent heat solar thermal energy storage materials – A review

International Nuclear Information System (INIS)

Raam Dheep, G.; Sreekumar, A.

2014-01-01

Highlights: • Classification of phase change materials. • Studies on phase change properties of various phase change materials. • Influence of nanomaterials on properties of phase change materials. - Abstract: Thermal energy storage system plays a critical role in developing an efficient solar energy device. As far as solar thermal devices are concerned, there is always a mismatch between supply and demand due to intermittent and unpredictable nature of solar radiation. A well designed thermal energy storage system is capable to alleviate this demerit by providing a constant energy delivery to the load. Many research works is being carried out to determine the suitability of thermal energy storage system to integrate with solar thermal gadgets. This review paper summarizes the numerous investigations on latent heat thermal energy storage using phase change materials (PCM) and its classification, properties, selection criteria, potential research areas and studies involved to analyze the thermal–physical properties of PCM

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

Directory of Open Access Journals (Sweden)

Smajo Sulejmanovic

2014-11-01

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

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

DEFF Research Database (Denmark)

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

2016-01-01

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

Thermal performance of a linear Fresnel reflector solar concentrator PV/T energy systems

Energy Technology Data Exchange (ETDEWEB)

Gomaa, Mohamed R. [State Engineering University of Armenia (Armenia)], E-Mail: Dmoh_elbehary@yahoo.com

2011-07-01

This is a report on an investigation of photovoltaic/thermal (PV/T) collectors. Solar energy conversion efficiency was increased by taking advantage of PV/T collectors and low solar concentration technologies, combined into a PV/T system operated at elevated temperature. The main novelty is the coupling of a linear Fresnel mirror reflecting concentrator with a channel PV/T collector. Concentrator PV/T collectors can function at temperatures over 100 degrees celsius, and thus thermal energy can be made to drive processes such as refrigeration, desalination and steam production. Solar system analytical thermal performance gives efficiency values over 60%. Combined electric and thermal (CET) efficiency is high. A combined electric and heat power for the linear fresnel reflector approach that employs high performance CPV technology to produce both electricity and thermal energy at low to medium temperatures is presented. A well-functioning PV/T system can be designed and constructed with low concentration and a total efficiency of nearly 80% can be attained.

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

Science.gov (United States)

Lotz, David Allen

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

Thermal solar energy in Spain. State of the art and objectives

International Nuclear Information System (INIS)

Glenn, Jaouen

2006-01-01

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

Study and modeling of energy performance of a hybrid photovoltaic/thermal solar collector: Configuration suitable for an indirect solar dryer

International Nuclear Information System (INIS)

Slimani, Mohamed El Amine; Amirat, Madjid; Bahria, Sofiane; Kurucz, Ildikó; Aouli, M’heni; Sellami, Rabah

2016-01-01

Highlights: • The simulation results are in compliance with the experimental measurements indicated in the previous literature. • The accuracy of the numerical model is due to the presented energy analysis and also to the well-adopted correlations. • A comparative study between two solar photovoltaic/thermal air collectors was carried out. • The thermal efficiency of the analyzed hybrid collector increased by 30.85% compared to the basic configuration. • The air temperature supplied by a double-pass photovoltaic/thermal collector is very suitable for solar drying. - Abstract: In this paper, a configuration of photovoltaic-thermal hybrid solar collector embeddable in an indirect solar dryer system is studied. In the present structure of the solar photovoltaic/thermal air collector, the air goes through a double pass below and above the photovoltaic module. A system of electrical and thermal balance equations is developed and analyzed governing various electric and heat transfer parameters in the solar hybrid air collector. The numerical model planned for this study gives a good precision of results, which are close to the experimental ones (of previous literature), and makes it possible to have a good assessment of energy performance regarding the studied configuration (temperature, electric and thermal powers, electrical and thermal efficiencies, etc.). The numerical results show the energy effectiveness of this hybrid collector configuration and particularly its interesting use in an indirect solar dryer system that provides a more suitable air temperature for drying agricultural products. The values of the electrical, thermal and overall energy efficiencies reaches 10.5%, 70% and 90% respectively, with a mass flow rate of 0.0155 kg/s and weather data sample for the month of June in the Algiers site. The results presented in this study also reveal how important the effect of certain parameters and operating conditions on the performance of the hybrid

Methane-steam reforming by molten salt - membrane reactor using concentrated solar thermal energy

International Nuclear Information System (INIS)

Watanuki, K.; Nakajima, H.; Hasegawa, N.; Kaneko, H.; Tamaura, Y.

2006-01-01

By utilization of concentrated solar thermal energy for steam reforming of natural gas, which is an endothermic reaction, the chemical energy of natural gas can be up-graded. The chemical system for steam reforming of natural gas with concentrated solar thermal energy was studied to produce hydrogen by using the thermal storage with molten salt and the membrane reactor. The original steam reforming module with hydrogen permeable palladium membrane was developed and fabricated. Steam reforming of methane proceeded with the original module with palladium membrane below the decomposition temperature of molten salt (around 870 K). (authors)

Buffer thermal energy storage for an air Brayton solar engine

Science.gov (United States)

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

1981-01-01

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

Solar thermal aided power generation

International Nuclear Information System (INIS)

Hu, Eric; Yang, YongPing; Nishimura, Akira; Yilmaz, Ferdi; Kouzani, Abbas

2010-01-01

Fossil fuel based power generation is and will still be the back bone of our world economy, albeit such form of power generation significantly contributes to global CO 2 emissions. Solar energy is a clean, environmental friendly energy source for power generation, however solar photovoltaic electricity generation is not practical for large commercial scales due to its cost and high-tech nature. Solar thermal is another way to use solar energy to generate power. Many attempts to establish solar (solo) thermal power stations have been practiced all over the world. Although there are some advantages in solo solar thermal power systems, the efficiencies and costs of these systems are not so attractive. Alternately by modifying, if possible, the existing coal-fired power stations to generate green sustainable power, a much more efficient means of power generation can be reached. This paper presents the concept of solar aided power generation in conventional coal-fired power stations, i.e., integrating solar (thermal) energy into conventional fossil fuelled power generation cycles (termed as solar aided thermal power). The solar aided power generation (SAPG) concept has technically been derived to use the strong points of the two technologies (traditional regenerative Rankine cycle with relatively higher efficiency and solar heating at relatively low temperature range). The SAPG does not only contribute to increase the efficiencies of the conventional power station and reduce its emission of the greenhouse gases, but also provides a better way to use solar heat to generate the power. This paper presents the advantages of the SAPG at conceptual level.

Spectrally-engineered solar thermal photovoltaic devices

Science.gov (United States)

Lenert, Andrej; Bierman, David; Chan, Walker; Celanovic, Ivan; Soljacic, Marin; Wang, Evelyn N.; Nam, Young Suk; McEnaney, Kenneth; Kraemer, Daniel; Chen, Gang

2018-03-27

A solar thermal photovoltaic device, and method of forming same, includes a solar absorber and a spectrally selective emitter formed on either side of a thermally conductive substrate. The solar absorber is configured to absorb incident solar radiation. The solar absorber and the spectrally selective emitter are configured with an optimized emitter-to-absorber area ratio. The solar thermal photovoltaic device also includes a photovoltaic cell in thermal communication with the spectrally selective emitter. The spectrally selective emitter is configured to permit high emittance for energies above a bandgap of the photovoltaic cell and configured to permit low emittance for energies below the bandgap.

Solar energy

International Nuclear Information System (INIS)

Anon.

1992-01-01

This chapter discusses the role solar energy may have in the energy future of the US. The topics discussed in the chapter include the solar resource, solar architecture including passive solar design and solar collectors, solar-thermal concentrating systems including parabolic troughs and dishes and central receivers, photovoltaic cells including photovoltaic systems for home use, and environmental, health and safety issues

Heating up the market with solar thermal energy; Mit Solarthermie den Markt aufheizen

Energy Technology Data Exchange (ETDEWEB)

Leukefeld, T. [Soli fer Solardach GmbH, Freiberg (Germany)

2006-07-01

Compared to the market for solar current, the market for solar thermal energy only grows slowly. The markets depends on subsidies and as soon as somebody reacts too slowly the sales are decreasing. It is typical for a pioneer product but unsuitable for our proven technology that solar thermal campaigns attempt to sell an ideology instead of addressing the latent purchasing readiness of the customer. The leading groups in the market who have a strong buying power remain sceptical, mostly they are not reached at all. A healthy growth of the solar thermal energy field in Germany can not be achieved like this. Why do the solar pioneers not have the economic success? Where do the variations come from, why are the sales increases behind the expectations? Where do we hamper ourselves, which obstacles in the market do we allow? This contribution reports on some hindrances based on own gained experience and evaluates them from different perspectives. (orig.)

Solar Energy Perspectives In Egypt

International Nuclear Information System (INIS)

Comsan, M.N.H.

2010-01-01

Egypt belongs to the global sun-belt. The country is in advantageous position with solar energy. In 1991 solar atlas for Egypt was issued indicating that the country enjoys 2900-3200 hours of sunshine annually with annual direct normal energy density 1970-3200 kWh/m2 and technical solar-thermal electricity generating potential of 73.6 Peta watt hour (PWh). Egypt was among the first countries to utilize solar energy. In 1910, a practical industrial scale solar system engine was built at Maadi south to Cairo using solar thermal parabolic collectors. The engine was used to produce steam which drove a series of large water pumps for irrigation. Nowadays utilization of solar energy includes use of photovoltaic cells, solar water heating and solar thermal power. Use of solar thermal technology may include both electricity generation and water desalination, which is advantageous for Egypt taking in consideration its shortage in water supply. The article discusses perspectives of solar energy in Egypt and developmental trends till 2050

Thermal analysis of a hybrid solar energy saving system inside a greenhouse

International Nuclear Information System (INIS)

Ntinas, G.K.; Fragos, V.P.; Nikita-Martzopoulou, Ch.

2014-01-01

Highlights: • A hybrid solar system consisted of water filled polyethylene sleeves was examined. • The thermal behaviour of the system was studied based on the sleeves energy balance. • Water temperature and heat exchanges of the sleeves were dynamically estimated. • Experimental data used to validate the predictions of the mathematical model. • The use of the system led to an energy saving of 23% inside a heated greenhouse. - Abstract: The intensive greenhouse energy requirements are a major operational and economical problem for producers around the world. Energy conservation techniques and innovative applications of solar energy for heating are being employed in greenhouse operation to reduce heating costs during cold periods. The present study investigated the development of a mathematical model to predict the thermal efficiency of a novel hybrid solar energy saving system inside a heated greenhouse. The solar system consisted of a transparent water-filled polyethylene sleeve and two perforated air-filled polyethylene tubes on the top peripheral sides of it. Above the sleeve and between the two tubes, rockwool substrates were placed for hydroponic cultivation of tomato crop. In order to validate this model, experiments were carried out in two identical parts of a polyethylene arched-type greenhouse to obtain data during winter. By comparing the measured and the predicted values, a correlation of 95% was found, indicating that the model can simulate the water temperature inside the hybrid solar sleeves. Moreover, the additional energy provided by the hybrid solar system reached approximately 23% during the examined period, depending on solar radiation levels

The SolarPACES strategy for the solar thermal breakthrough

Energy Technology Data Exchange (ETDEWEB)

Burch, G.D. [U.S. Department of Energy, Washington, DC (United States)

1997-12-31

Our national solar thermal research programs and our combined efforts conducted through IEA/SolarPACES have brought about many breakthroughs in the development of solar thermal technology. We have components and systems that are much more efficient, much more reliable, and can be built much more cost-efficiently than just a few years ago. As our technology development proceeds, we undoubtedly will continue to make significant progress, breakthroughs in fact, in all these areas - progress that will bring us even closer to economic parity with more conventional forms of energy. And while this progress is absolutely necessary, the question is whether it will be enough to allow solar thermal to break into the mainstream of global energy supply. Our new IEA/SolarPACES strategy, crafted and approved over the course of the past year, has recognized the changes we must face and given us license to begin to make those changes. We must begin addressing financial hurdles, work to create a more favorable regulatory and tax environment, support development of international partnerships, and expand the visibility and excitement of solar thermal technology to achieve the final breakthroughs we need to allow solar thermal energy to live up to its vast potential. (orig./AKF)

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)

The SERI solar energy storage program

Science.gov (United States)

Copeland, R. J.; Wright, J. D.; Wyman, C. E.

1980-01-01

In support of the DOE thermal and chemical energy storage program, the solar energy storage program (SERI) provides research on advanced technologies, systems analyses, and assessments of thermal energy storage for solar applications in support of the Thermal and Chemical Energy Storage Program of the DOE Division of Energy Storage Systems. Currently, research is in progress on direct contact latent heat storage and thermochemical energy storage and transport. Systems analyses are being performed of thermal energy storage for solar thermal applications, and surveys and assessments are being prepared of thermal energy storage in solar applications. A ranking methodology for comparing thermal storage systems (performance and cost) is presented. Research in latent heat storage and thermochemical storage and transport is reported.

Solar thermal energy utilization. German studies on technology and application. Vol. 1. General investigations on energy availability

Energy Technology Data Exchange (ETDEWEB)

Becker, M. (Deutsche Forschungs- und Versuchsanstalt fuer Luft- und Raumfahrt e.V. (DFVLR), Koeln (Germany, F.R.). Hauptabteilung Energietechnik) (ed.)

1987-01-01

The first volume of a three-volume series titled 'Solar thermal energy utilization' comprises three papers dealing with general investigations into energy availability. Their titles are: Yearly yield of solar CRS-process heat and temperature of reaction; - literature survey in the field of primary and secondary concentrating solar energy systems concerning the choice and manufacturing process of suitable materials; - considerations and proposals for future research and development of high temperature solar processes. Each of the three chapters was abstracted for entry into the database. (HWJ).

New thermal energies in France. Solar, biomass, geothermal and aero-thermal: which perspectives by 2015?

International Nuclear Information System (INIS)

2012-01-01

Whereas thermal renewable energies are to become inescapable, and notably 'green heat' which is acclaimed by real estate professionals as well as by industries, their market is foreseen to grow at a rate of 6 per cent a year until 2015. This high rate is notably due to the soaring price of conventional energies like electricity, gas or oil fuel, but also to environmental constraints related to the reduction of greenhouse gas emissions. A first part proposes an overview of the French market of new sources of thermal renewable energies for a domestic use in 2011, and discusses perspectives by 2015. A detailed analysis of the three main technologies (heat pumps, thermal solar devices, wood fuelled domestic heating devices) is proposed and challenges faced by involved enterprises and possible answers provided by professionals are also detailed. A second part gathers and comments data related to thermal energy production for industrial and collective use (in collective housing and office building): energy production level, legal and regulatory framework, evolution of demand, predictions for the different energy sources (wood energy, geothermal, waste energetic valorisation). It also proposes an analysis of stakes related to these applications. The third part proposes an assessment of the size of the different sectors by presenting key economic figures (turnover, staff, etc.). While the fourth part proposes an overview of leaders for each sector (thermal solar, biomass, and heat pump) and a more detailed presentation of 14 important actors, the fifth and last part proposes a large set of financial and economic indicators of 200 involved operators

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

Directory of Open Access Journals (Sweden)

Theebhan Mogana

2016-01-01

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

Solar Energy Technician/Installer

Science.gov (United States)

Moore, Pam

2007-01-01

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

Solar engineering of thermal processes

CERN Document Server

Duffie, John A

2013-01-01

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

Solar-thermal energy - How progress will be made

International Nuclear Information System (INIS)

Frei, U.; Hawkins, A. C.

2004-01-01

This second part of a two-part article is based on a lecture given by professor Ueli Frei of the University of Applied Science in Rapperswil, Switzerland. It discusses present and future system technologies that can be used for thermal applications of solar energy. The importance of correct engineering and planning is stressed. The evolution of solar collector technology since 1980 is examined and the important progress made in this area is looked at. A selection of graphical representations illustrate the progress that has already been made and that which can be expected in the future

Development of road hydronic snow-ice melting system with solar energy and seasonal underground thermal energy storage

Energy Technology Data Exchange (ETDEWEB)

Gao, Q.; Liu, Y.; Ma, C.Q.; Li, M.; Huang, Y.; Yu, M. [Jilin Univ., Changchun (China). Dept. of Thermal Energy Engineering; Liu, X.B. [Climate Master Inc., OK (United States)

2008-07-01

Snow and ice melting technologies that used thermal energy storage were explored. The study included analyses of solar heat slab, seasonal underground thermal energy storage, and embedded pipe technologies. Different road materials, roadbed construction methods, and underground rock and soil conditions were also discussed. New processes combining all 3 of the main technologies were also reviewed. Other thermal ice melting technologies included conductive concrete and asphalt; heating cables, and hydronic melting systems. Geothermal energy is increasingly being considered as a means of melting snow and ice from roads and other infrastructure. Researchers have also been focusing on simulating heat transfer in solar collectors and road-embedded pipes. Demonstration projects in Japan, Switzerland, and Poland are exploring the use of combined geothermal and solar energy processes to remove snow and ice from roads. Research on hydronic melting technologies is also being conducted in the United States. The study demonstrated that snow-ice melting energy storage systems will become an important and sustainable method of snow and ice removal in the future. The technology efficiently uses renewable energy sources, and provides a cost-effective means of replacing or reducing chemical melting agents. 33 refs., 1 fig.

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

Science.gov (United States)

Ehrke, Elizabeth

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

Solar energy: a UK assessment

Energy Technology Data Exchange (ETDEWEB)

1976-01-01

A panel convened by UK-ISES to analyze all aspects of solar energy systems and to assess the potential for solar energy utilization and research and development needs in the UK and for export is reported. Topics covered include: solar energy in relation to other energy sources; international solar energy research and development program; the physical nature of solar energy and its availability in the UK and other countries; thermal collection, storage, and low-temperature applications; solar energy and architecture; solar thermal power systems; solar cells; agricultural and biological systems; photochemical systems; social, legal, and political considerations with particular reference to the UK; and future policy on solar research and development for the UK. (WDM)

A comparative study on three types of solar utilization technologies for buildings: Photovoltaic, solar thermal and hybrid photovoltaic/thermal systems

International Nuclear Information System (INIS)

Huide, Fu; Xuxin, Zhao; Lei, Ma; Tao, Zhang; Qixing, Wu; Hongyuan, Sun

2017-01-01

Highlights: • Models of Solar thermal, Photovoltaic and Photovoltaic/thermal systems are developed. • Experiments are performed to validate the simulation results. • Annual performances of the three solar systems used in china are predicted. • Energy comparison between the three solar systems is analyzed. - Abstract: Buildings need energy including heat and electricity, and both of them can be provided by the solar systems. Solar thermal and photovoltaic systems absorb the solar energy and can supply the heat and electricity for buildings, respectively. However, for the urban residential buildings, the limited available area makes installation of the solar thermal collectors and photovoltaic modules together impossible. A hybrid photovoltaic/thermal system can simultaneously generate heat and electricity, which is deemed to be quite suitable for the urban residential buildings application. And yet, for a rural house of China, the available area for installation of the solar collectors is large but daily domestic hot water demand of a rural family is generally not exceeded 300 L. If only the hybrid photovoltaic/thermal collectors are installed on the whole available area, this will lead to an overproduction of the thermal energy, especially in summer. Moreover, buildings requiring for the heat and electricity are different in different regions and different seasons. In this paper, simulation models of the solar thermal, photovoltaic and hybrid photovoltaic/thermal systems are presented, and experiments are also performed to validate the simulation results. Using the validated models, performances of the three solar systems for residential applications were predicted. And energy comparison between the three solar systems used in Hongkong, Lhasa, Shanghai and Beijing of China, respectively, were also studied. Results show that, for the urban residential building with limited available installation space, a hybrid photovoltaic/thermal system may have the

Solar energy guide

International Nuclear Information System (INIS)

Lentz, A.; Winter, R.

1993-07-01

Many aspects with regard to the practical use of solar energy are discussed. This guide is aimed at informing local and regional administrators, committee members of housing corporations and public utilities and public relations officers on the possibilities to use solar energy. In chapter one an overview is given of the use of solar energy in the housing sector, the recreational sector, agricultural sector, industry, trade and other sectors. In the chapters two, three and four attention is paid to passive solar energy, active thermal solar energy and photovoltaic energy respectively. In the chapters five and six aspects concerning the implementation of solar energy systems in practice are discussed. First an outline of the parties involved in implementing solar energy is given: the municipality, the energy utility, the province, local authorities, advisors, housing constructors and the occupants of the buildings. Then attention is paid to the consequences of implementing solar energy for the building inspection and regulations, the finances, energy savings and the environment. In chapter seven an overview is given of the subsidy regulations of the European Community, the Dutch national and local governments. Chapter contains addresses of solar thermal systems, photovoltaic systems and other institutes operating in the field of solar energy, as well as the titles of a number of brochures and courses. 51 figs., 7 tabs., 86 refs

Renewable energy worldwide outlooks: solar energy

International Nuclear Information System (INIS)

Darnell, J.R.

1994-01-01

Solar energy yield is weak because it is very diffuse. The solar energy depends on the weather. The collectors need the beam radiation. Wavelength is important for some applications that include not only the visible spectrum but also infrared and ultraviolet radiation. The areas of the greatest future population growth are high on solar energy resources. We have different types of conversion systems where energy can be converted from solar to electric or thermal energy. Photovoltaic cells are made of silicone or gallium arsenide, this latter for the space use. For the solar energy applications there is a storage problem: electric batteries or superconducting magnets. Today, the highest use of solar energy is in the low temperature thermal category with over 90% of the world contribution from this energy. The penetration of solar energy will be higher in rural areas than in urban regions. But there are technical, institutional, economic constraints. In spite of that the use of solar energy would be increasing and will go on to increase thereafter. The decreasing costs over time are a real phenomenon and there is a broad public support for increased use of that energy. 15 figs

Buffer thermal energy storage for a solar Brayton engine

Science.gov (United States)

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

1981-01-01

A study has been completed on the application of latent-heat buffer thermal energy storage to a point-focusing solar receiver equipped with an air Brayton engine. To aid in the study, a computer program was written for complete transient/stead-state Brayton cycle performance. The results indicated that thermal storage can afford a significant decrease in the number of engine shutdowns as compared to operating without thermal storage. However, the number of shutdowns does not continuously decrease as the storage material weight increases. In fact, there appears to be an optimum weight for minimizing the number of shutdowns.

Analysis of dynamic effects in solar thermal energy conversion systems

Science.gov (United States)

Hamilton, C. L.

1978-01-01

The paper examines a study the purpose of which is to assess the performance of solar thermal power systems insofar as it depends on the dynamic character of system components and the solar radiation which drives them. Using a dynamic model, the daily operation of two conceptual solar conversion systems was simulated under varying operating strategies and several different time-dependent radiation intensity functions. These curves ranged from smoothly varying input of several magnitudes to input of constant total energy whose intensity oscillated with periods from 1/4 hour to 6 hours.

Volumetric solar thermal receiver principles and technological approach

International Nuclear Information System (INIS)

Sagie, D.; Gruntman, S.; Taragan, E.; Danino, M.; Weiss, S.; Mimon, Y.

1996-01-01

Solar energy has received much interest in recent years, being a clean free of pollution or other environmental dotage), and inexhaustible energy source. It is also considered safer than some other non conventional energy sources (like nuclear energy). The interest in solar energy is motivated mainly by the growing awareness of the environmental problems associated with the use of . conventional keels. However, solar energy may become a serious alternative only if it can be used efficiently in major energy consuming industries (like the chemical industry), or be used for electricity generation. Those facilities are nowadays solely depend on fossil fuels as the prime source of energy . The solar energy, reaches file Earth as radiation, can be utilized either by direct quantum conversion using photo-voltaic solar cells, or by converting the radiation into thermal energy, to be used directly for heating, or to feed a thermal to electric converting cycle. Alter three decades of huge spending on the development of photo-voltaic systems those devices are commercially competitive only on very small energy scale, while solar thermal commercial applications are evident. The prominent examples are the domestic heating water receivers (direct thermal), and LUZ International electricity generation plants which are currently operated on a commercial basis, supplying 80 MWe per plant. Direct thermal exploitation of solar energy is naturally more efficient than converting to electricity but is limited to specific applications and locations especially since thermal storage at high temperature is not commercially viable. Efficient electricity production at competitive price is clearly the biggest opportunity for solar energy. (authors)

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

Science.gov (United States)

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

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

Perspectives for solar thermal applications in Taiwan

International Nuclear Information System (INIS)

Chang, Keh-Chin; Lin, Wei-Min; Leu, Tzong-Shyng; Chung, Kung-Ming

2016-01-01

Taiwan has long depended on imported fossil energy. The government is thus actively promoting the use of renewable energy. Since 2000, domestic installations of solar water heaters have increased substantially because of the long-term subsidies provided for such systems. However, data on the annual installation area of solar collectors in recent years indicated that the solar thermal industry in Taiwan has reached a bottleneck. The long-term policy providing subsidies must thus be revised. It is proposed that future thermal applications in Taiwan should focus on building-integrated solar thermal, photovoltaic/thermal, and industrial heating processes. Regarding building-integrated solar thermal systems, the current subsidy model can be continued (according to area of solar collectors); nevertheless, the application of photovoltaic/thermal and industrial heating systems must be determined according to the thermal output of such systems. - Highlights: •The long-term subsidization for solar water heaters has lost effectiveness. •Solar thermal applications include BIST, PV/T and industrial heating process. •A performance-based subsidy policy should be implemented.

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

Energy Technology Data Exchange (ETDEWEB)

Rosell, J.; Chemisana, D.

2009-07-01

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

Solar energy

International Nuclear Information System (INIS)

Kruisheer, N.

1992-01-01

In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills

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

Science.gov (United States)

Williams, J. R.

1974-01-01

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

Solar thermal production of zinc: Program strategy

Energy Technology Data Exchange (ETDEWEB)

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

1999-08-01

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

Cost/benefit comparison of thermal solar energy systems in Switzerland

International Nuclear Information System (INIS)

Suter, J.M.

1991-10-01

A comparison is made between thermal solar energy systems of different size for five different applications in the three main climatic zones in Switzerland. Conventional ways of energy conservation are also included in the comparison. A cost/benefit ratio is calculated for each system. The investment is used as a cost indicator whereas the useful solar heat or the conventional energy saving is chosen as benefit. It is shown that the most systems sold today in Switzerland - combined hot water and space heating systems for single family houses - have the poorest cost/benefit ratio among all systems considered in the analysis. Four applications with more favourable cost/benefit ratio are identified. Large systems have generally a better cost/benefit ratio than smaller ones, although the total investment is higher. Photovoltaics is even less favourable than all thermal systems considered. The large scale penetration of technologies with good cost/benefit ratio lies in the public interest. Supporting activities should consider the priority set by the cost/benefit ratio. (author) 1 fig., 14 refs

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

Science.gov (United States)

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

1985-01-01

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

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

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

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

Phase change thermal storage for a solar total energy system

Science.gov (United States)

Rice, R. E.; Cohen, B. M.

1978-01-01

An analytical and experimental program is being conducted on a one-tenth scale model of a high-temperature (584 K) phase-change thermal energy storage system for installation in a solar total energy test facility at Albuquerque, New Mexico, U.S.A. The thermal storage medium is anhydrous sodium hydroxide with 8% sodium nitrate. The program will produce data on the dynamic response of the system to repeated cycles of charging and discharging simulating those of the test facility. Data will be correlated with a mathematical model which will then be used in the design of the full-scale system.

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.

Candidate thermal energy storage technologies for solar industrial process heat applications

Science.gov (United States)

Furman, E. R.

1979-01-01

A number of candidate thermal energy storage system elements were identified as having the potential for the successful application of solar industrial process heat. These elements which include storage media, containment and heat exchange are shown.

Polymeric materials for solar thermal applications

CERN Document Server

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

2012-01-01

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

Solar energy: Technology and applications

Science.gov (United States)

Williams, J. R.

1974-01-01

It is pointed out that in 1970 the total energy consumed in the U.S. was equal to the energy of sunlight received by only 0.15% of the land area of the continental U.S. The utilization of solar energy might, therefore, provide an approach for solving the energy crisis produced by the consumption of irreplaceable fossil fuels at a steadily increasing rate. Questions regarding the availability of solar energy are discussed along with the design of solar energy collectors and various approaches for heating houses and buildings by utilizing solar radiation. Other subjects considered are related to the heating of water partly or entirely with solar energy, the design of air conditioning systems based on the use of solar energy, electric power generation by a solar thermal and a photovoltaic approach, solar total energy systems, industrial and agricultural applications of solar energy, solar stills, the utilization of ocean thermal power, power systems based on the use of wind, and solar-energy power systems making use of geosynchronous power plants.

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-03-30

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

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.

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.

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.

Fuels and chemicals from biomass using solar thermal energy

Science.gov (United States)

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

1981-01-01

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

Cheap effective thermal solar-energy collectors

Energy Technology Data Exchange (ETDEWEB)

Highgate, D.J.; Probert, S.D. [Cranfield University, Bedford (United Kingdom). Dept. of Applied Energy

1996-04-01

A light-weight flexible solar-collector, with a wavelength-selective absorption surface and an insolation-transparent thermal-insulation protecter for its aperture, was built and tested. Its cheapness and high performance, relative to a conventional flat-plate solar-collector, provide a prima-facie case for the more widespread adoption of its design. (author)

Thermal energy storage for solar power generation - State of the art

Science.gov (United States)

Shukla, K. N.

1981-12-01

High temperature storage for applications in solar-thermal electric systems is considered. Noting that thermal storage is in either the form of latent, sensible or chemically stored heat, sensible heat storage is stressed as the most developed of the thermal storage technologies, spanning direct heating of a storage medium from 120-1250 C. Current methods involve solids, packed beds, fluidized beds, liquids, hot water, organic liquids, and inorganic liquids and molten salts. Latent heat storage comprises phase-change materials that move from solid to liquid with addition of heat and liquid to solid with the removal of heat. Metals or inorganic salts are candidates, and the energy balances are outlined. Finally, chemical heat storage is examined, showing possible high energy densities through catalytic, thermal dissociation reactions.

A survey of manufacturers of solar thermal energy systems

Science.gov (United States)

Levine, N.; Slonski, M. L.

1982-01-01

Sixty-seven firms that had received funding for development of solar thermal energy systems (STES) were surveyed. The effect of the solar thermal technology systems program in accelerating (STES) were assessed. The 54 firms still developing STES were grouped into a production typology comparing the three major technologies with three basic functions. It was discovered that large and small firms were developing primarily central receiver systems, but also typically worked on more than one technology. Most medium-sized firms worked only on distributed systems. Federal support of STES was perceived as necessary to allow producers to take otherwise unacceptable risks. Approximately half of the respondents would drop out of STES if support were terminated, including a disproportionate number of medium-sized firms. A differentiated view of the technology, taking into account differing firm sizes and the various stages of technology development, was suggested for policy and planning purposes.

Solar Thermal Utilization: Past, Present and Future

Science.gov (United States)

2010-09-01

SO•C NON-FOCUSSING FLAT PLATE / (FPC) 100- 150•C For low temperature 50- 200•C COMPOUND applications PARABOLIC EVACUATED CONCENTRATOR ~ (ETC...2030 Ø 200GW BY 2050 Ø 20 MILLION SQ.METER SOLAR THERMAL COLLECTORS (20GW power) Ø 20 MILLION SOLAR LIGHTS LAUNCHING OF SOLAR INDIA SOLAR THERMAL...Temperature (20oC- 80oC) NALSUN ApplicationsThermal Conversion range SOLAR ENERGY COLLECTORS 40- GO•C UNGLAZED COLLECTORS 60- 90•C SOLAR POND 60

Nanostructured Solar Irradiation Control Materials for Solar Energy Conversion

Science.gov (United States)

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

High-temperature molten salt thermal energy storage systems for solar applications

Science.gov (United States)

Petri, R. J.; Claar, T. D.; Ong, E.

1983-01-01

Experimental results of compatibility screening studies of 100 salt/containment/thermal conductivity enhancement (TCE) combinations for the high temperature solar thermal application range of 704 deg to 871 C (1300 to 1600 F) are presented. Nine candidate containment/HX alloy materials and two TCE materials were tested with six candidate solar thermal alkali and alkaline earth carbonate storage salts (both reagent and technical grade of each). Compatibility tests were conducted with salt encapsulated in approx. 6.0 inch x 1 inch welded containers of test material from 300 to 3000 hours. Compatibility evaluations were end application oriented, considering the potential 30 year lifetime requirement of solar thermal power plant components. Analyses were based on depth and nature of salt side corrosion of materials, containment alloy thermal aging effects, weld integrity in salt environment, air side containment oxidation, and chemical and physical analyses of the salt. A need for more reliable, and in some cases first time determined thermophysical and transport property data was also identified for molten carbonates in the 704 to 871 C temperature range. In particular, accurate melting point (mp) measurements were performed for Li2CO3 and Na2CO3 while melting point, heat of fusion, and specific heat determinations were conducted on 81.3 weight percent Na2CO3-18.7 weight percent K2CO3 and 52.2 weight percent BaCO3-47.8 weight percent Na2CO3 to support future TES system design and ultimate scale up of solar thermal energy storage (TES) subsystems.

New combined plant with integrated solar thermal energy; Neue Kombi-Anlage mit integrierter Solarwaerme

Energy Technology Data Exchange (ETDEWEB)

Leithner, R.; Dobrowolski, R.; Gresch, H. [Technische Univ. Braunschweig (Germany). Inst. fuer Waerme- und Brennstofftechnik

1998-06-01

In California there are already 350 MW{sub e} worth of solar thermal energy plants in operation on a more or less commercial basis. In these installations thermal oil in parabolic gutters is heated from 300 C to 400 C. The thermal oil passes its thermal energy on to a water vapour circuit via a heat exchanger. The water vapour circuit can also be heated with natural gas, for instance at night when solar energy is not available. However, as yet no existing plant fulfils all three of the following requirements: its construction should entail the lowest possible investment costs and it should be able to run without solar energy and without an expensive storage system; it should have the greatest possible efficiency, especially at times when solar energy is not available (e.g. at night); at the same time, the solar thermal energy should be harvested at the lowest possible temperature so as to make expensive concentrating equipment superfluous. These seemingly contradictory demands are now met by a new concept involving a combined gas and steam plant whose operation is based on the injection of water into the compressed air rather than on a high excess of air. This water is evaporated by solar thermal energy at temperatures below 170 C according to its partial pressure. [Deutsch] Es gibt bereits ueber 350 MWe solarthermische Anlagen in Kalifornien, die mehr oder weniger kommerziell betrieben werden. Bei diesen Anlagen wird Thermaloel von 300 C auf 400 C in Parabolrinnen erhitzt. In einem Waermetauscher gibt das Thermaloel die Waerme an einen Wasserdampfkreislauf ab, der auch mit Erdgas beheizt werden kann, wenn wie z.B. nachts keine Solarwaerme verfuegbar ist. In einem weiteren Schritt wurde vorgeschlagen, das Wasser direkt zu verdampfen. Keine dieser Anlagen genuegt jedoch gleichzeitig den folgenden drei Anforderungen: Die Anlage sollte mit moeglichst niedrigen Investitionskosten gebaut und auch ohne Solarwaerme bzw. ohne aufwendigen Speicher betrieben werden koennen

Molecularly Engineered Azobenzene Derivatives for High Energy Density Solid-State Solar Thermal Fuels.

Science.gov (United States)

Cho, Eugene N; Zhitomirsky, David; Han, Grace G D; Liu, Yun; Grossman, Jeffrey C

2017-03-15

Solar thermal fuels (STFs) harvest and store solar energy in a closed cycle system through conformational change of molecules and can release the energy in the form of heat on demand. With the aim of developing tunable and optimized STFs for solid-state applications, we designed three azobenzene derivatives functionalized with bulky aromatic groups (phenyl, biphenyl, and tert-butyl phenyl groups). In contrast to pristine azobenzene, which crystallizes and makes nonuniform films, the bulky azobenzene derivatives formed uniform amorphous films that can be charged and discharged with light and heat for many cycles. Thermal stability of the films, a critical metric for thermally triggerable STFs, was greatly increased by the bulky functionalization (up to 180 °C), and we were able to achieve record high energy density of 135 J/g for solid-state STFs, over a 30% improvement compared to previous solid-state reports. Furthermore, the chargeability in the solid state was improved, up to 80% charged from 40% charged in previous solid-state reports. Our results point toward molecular engineering as an effective method to increase energy storage in STFs, improve chargeability, and improve the thermal stability of the thin film.

solar thermal power systems advanced solar thermal technology project, advanced subsystems development

Science.gov (United States)

1979-01-01

The preliminary design for a prototype small (20 kWe) solar thermal electric generating unit was completed, consisting of several subsystems. The concentrator and the receiver collect solar energy and a thermal buffer storage with a transport system is used to provide a partially smoothed heat input to the Stirling engine. A fossil-fuel combustor is included in the receiver designs to permit operation with partial or no solar insolation (hybrid). The engine converts the heat input into mechanical action that powers a generator. To obtain electric power on a large scale, multiple solar modules will be required to operate in parallel. The small solar electric power plant used as a baseline design will provide electricity at remote sites and small communities.

Photovoltaic. Solar thermal. Solar thermal electricity;Le Photovoltaique. Le solaire thermique. L'heliothermodynamique

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

The year 2008 was excellent for solar energy in the European Union. The growth of the installed capacity for photovoltaic was +159% (it means +4747.018 MW) to reach 9689.952 MW and that for solar thermal was +51.5% (it means +3172.5 MW) to reach 19982.7 MW. Worldwide concentrated solar thermal capacity stood at 679 MW in 2009, while this figure may seem low, the sector has a promising future ahead of it. (A.C.)

Solar thermal

International Nuclear Information System (INIS)

Jones, J.

2006-01-01

While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m 3 - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become increasingly important as

Solar thermal

Energy Technology Data Exchange (ETDEWEB)

Jones, J.

2006-07-15

While wind power is widely acknowledged as the most developed of the 'new' renewables, the number two technology, in terms of installed capacity functioning worldwide, is solar heating, or solar thermal. The author has investigated recent industry reports on how these markets are developing. The authors of an International Energy Agency (IEA) survey studied 41 countries in depth at the end of 2004, revealing that 141 million m{sup 3} - corresponding to an installed capacity of 98.4 GWth - were installed in the sample countries (these nations represent 3.74 billion people, about 57% of the world's population). The installed capacity within the areas studied represents approximately 85%-90% of the solar thermal market worldwide. The use of solar heating varies greatly between countries - even close neighbours - and between economic regions. Its uptake often has more to do with policy than solar resource. There is also different uptake of technology. In China, Europe and Japan, plants with flat-plate and evacuated tube collectors are used, mainly to heat water and for space heating. Unglazed plastic collectors, used mainly for swimming pool heating, meanwhile, dominate the North American markets. Though the majority of solar heating installations today are installed on domestic rooftops, the larger-scale installations should not be overlooked. One important part of the market is the hotel sector - in particular hotels in locations that serve the seasonal summer holiday market, where solar is extremely effective. Likewise hospitals and residential homes, multi-family apartment blocks and sports centres are all good examples of places where solar thermal can deliver results. There are also a growing number of industrial applications, where solar thermal can meet the hot water needs (and possibly more) of a range of industries, such as food processing and agriculture. The ability of solar to provide a heat source for cooling is expected to become

Detailed partial load investigation of a thermal energy storage concept for solar thermal power plants with direct steam generation

Science.gov (United States)

Seitz, M.; Hübner, S.; Johnson, M.

2016-05-01

Direct steam generation enables the implementation of a higher steam temperature for parabolic trough concentrated solar power plants. This leads to much better cycle efficiencies and lower electricity generating costs. For a flexible and more economic operation of such a power plant, it is necessary to develop thermal energy storage systems for the extension of the production time of the power plant. In the case of steam as the heat transfer fluid, it is important to use a storage material that uses latent heat for the storage process. This leads to a minimum of exergy losses during the storage process. In the case of a concentrating solar power plant, superheated steam is needed during the discharging process. This steam cannot be superheated by the latent heat storage system. Therefore, a sensible molten salt storage system is used for this task. In contrast to the state-of-the-art thermal energy storages within the concentrating solar power area of application, a storage system for a direct steam generation plant consists of a latent and a sensible storage part. Thus far, no partial load behaviors of sensible and latent heat storage systems have been analyzed in detail. In this work, an optimized fin structure was developed in order to minimize the costs of the latent heat storage. A complete system simulation of the power plant process, including the solar field, power block and sensible and latent heat energy storage calculates the interaction between the solar field, the power block and the thermal energy storage system.

Optically Transparent Thermally Insulating Silica Aerogels for Solar Thermal Insulation.

Science.gov (United States)

Günay, A Alperen; Kim, Hannah; Nagarajan, Naveen; Lopez, Mateusz; Kantharaj, Rajath; Alsaati, Albraa; Marconnet, Amy; Lenert, Andrej; Miljkovic, Nenad

2018-04-18

Rooftop solar thermal collectors have the potential to meet residential heating demands if deployed efficiently at low solar irradiance (i.e., 1 sun). The efficiency of solar thermal collectors depends on their ability to absorb incoming solar energy and minimize thermal losses. Most techniques utilize a vacuum gap between the solar absorber and the surroundings to eliminate conduction and convection losses, in combination with surface coatings to minimize reradiation losses. Here, we present an alternative approach that operates at atmospheric pressure with simple, black, absorbing surfaces. Silica based aerogels coated on black surfaces have the potential to act as simple and inexpensive solar thermal collectors because of their high transmission to solar radiation and low transmission to thermal radiation. To demonstrate their heat-trapping properties, we fabricated tetramethyl orthosilicate-based silica aerogels. A hydrophilic aerogel with a thickness of 1 cm exhibited a solar-averaged transmission of 76% and thermally averaged transmission of ≈1% (at 100 °C). To minimize unwanted solar absorption by O-H groups, we functionalized the aerogel to be hydrophobic, resulting in a solar-averaged transmission of 88%. To provide a deeper understanding of the link between aerogel properties and overall efficiency, we developed a coupled radiative-conductive heat transfer model and used it to predict solar thermal performance. Instantaneous solar thermal efficiencies approaching 55% at 1 sun and 80 °C were predicted. This study sheds light on the applicability of silica aerogels on black coatings for solar thermal collectors and offers design priorities for next-generation solar thermal aerogels.

Phase-Change Thermal Energy Storage

Science.gov (United States)

1989-11-01

The goal of this program is to advance the engineering and scientific understanding of solar thermal technology and to establish the technology base from which private industry can develop solar thermal power production options for introduction into the competitive energy market. Solar thermal technology concentrates the solar flux using tracking mirrors or lenses onto a receiver where the solar energy is absorbed as heat and converted into electricity or incorporated into products as process heat. The two primary solar thermal technologies, central receivers and distributed receivers, employ various point and line-focus optics to concentrate sunlight. Current central receiver systems use fields of heliostats (two-axes tracking mirrors) to focus the sun's radiant energy onto a single, tower-mounted receiver. Point focus concentrators up to 17 meters in diameter track the sun in two axes and use parabolic dish mirrors or Fresnel lenses to focus radiant energy onto a receiver. Troughs and bowls are line-focus tracking reflectors that concentrate sunlight onto receiver tubes along their focal lines. Concentrating collector modules can be used alone or in a multimodule system. The concentrated radiant energy absorbed by the solar thermal receiver is transported to the conversion process by a circulating working fluid. Receiver temperatures range from 100 C in low-temperature troughs to over 1500 C in dish and central receiver systems.

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

Directory of Open Access Journals (Sweden)

Alexandre Hugo

2012-10-01

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

Integration of solar thermal for improved energy efficiency in low-temperature-pinch industrial processes

International Nuclear Information System (INIS)

Atkins, Martin J.; Walmsley, Michael R.W.; Morrison, Andrew S.

2010-01-01

Solar thermal systems have the potential to provide renewable industrial process heat and are especially suited for low pinch temperature processes such as those in the food, beverage, and textile sectors. When correctly integrated within an industrial process, they can provide significant progress towards both increased energy efficiency and reduction in emissions. However, the integration of renewable solar energy into industrial processes presents a challenge for existing process integration techniques due to the non-continuous nature of the supply. A thorough pinch analysis study of the industrial process, taking in to account non-continuous operating rates, should be performed to evaluate the utility demand profile. Solar collector efficiency data under variable climatic conditions should also be collected for the specific site. A systematic method of combining this information leads to improved design and an optimal operating strategy. This approach has been applied to a New Zealand milk powder plant and benefits of several integration strategies, including mass integration, are investigated. The appropriate placement of the solar heat is analogous to the placement of a hot utility source and an energy penalty will be incurred when the solar thermal system provides heat below the pinch temperature.

Integration of solar thermal for improved energy efficiency in low-temperature-pinch industrial processes

Energy Technology Data Exchange (ETDEWEB)

Atkins, Martin J.; Walmsley, Michael R.W.; Morrison, Andrew S. [Energy Research Group, School of Science and Engineering, University of Waikato, Private Bag 3105, Hamilton 3240 (New Zealand)

2010-05-15

Solar thermal systems have the potential to provide renewable industrial process heat and are especially suited for low pinch temperature processes such as those in the food, beverage, and textile sectors. When correctly integrated within an industrial process, they can provide significant progress towards both increased energy efficiency and reduction in emissions. However, the integration of renewable solar energy into industrial processes presents a challenge for existing process integration techniques due to the non-continuous nature of the supply. A thorough pinch analysis study of the industrial process, taking in to account non-continuous operating rates, should be performed to evaluate the utility demand profile. Solar collector efficiency data under variable climatic conditions should also be collected for the specific site. A systematic method of combining this information leads to improved design and an optimal operating strategy. This approach has been applied to a New Zealand milk powder plant and benefits of several integration strategies, including mass integration, are investigated. The appropriate placement of the solar heat is analogous to the placement of a hot utility source and an energy penalty will be incurred when the solar thermal system provides heat below the pinch temperature. (author)

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…

Dish concentrators for solar thermal energy - Status and technology development

Science.gov (United States)

Jaffe, L. D.

1981-01-01

Comparisons are presented of point-focusing, or 'dish' solar concentrator system features, development status, and performance levels demonstrated to date. In addition to the requirements of good optical efficiency and high geometric concentration ratios, the most important future consideration in solar thermal energy dish concentrator design will be the reduction of installed and lifetime costs, as well as the materials and labor costs of production. It is determined that technology development initiatives are needed in such areas as optical materials, design wind speeds and wind loads, structural configuration and materials resistance to prolonged exposure, and the maintenance of optical surfaces. The testing of complete concentrator systems, with energy-converting receivers and controls, is also necessary. Both reflector and Fresnel lens concentrator systems are considered.

Hybrid energy harvesting using active thermal backplane

Science.gov (United States)

Kim, Hyun-Wook; Lee, Dong-Gun

2016-04-01

In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

Molecular solar thermal energy storage in photoswitch oligomers increases energy densities and storage times.

Science.gov (United States)

Mansø, Mads; Petersen, Anne Ugleholdt; Wang, Zhihang; Erhart, Paul; Nielsen, Mogens Brøndsted; Moth-Poulsen, Kasper

2018-05-16

Molecular photoswitches can be used for solar thermal energy storage by photoisomerization into high-energy, meta-stable isomers; we present a molecular design strategy leading to photoswitches with high energy densities and long storage times. High measured energy densities of up to 559 kJ kg -1 (155 Wh kg -1 ), long storage lifetimes up to 48.5 days, and high quantum yields of conversion of up to 94% per subunit are demonstrated in norbornadiene/quadricyclane (NBD/QC) photo-/thermoswitch couples incorporated into dimeric and trimeric structures. By changing the linker unit between the NBD units, we can at the same time fine-tune light-harvesting and energy densities of the dimers and trimers so that they exceed those of their monomeric analogs. These new oligomers thereby meet several of the criteria to be met for an optimum molecule to ultimately enter actual devices being able to undergo closed cycles of solar light-harvesting, energy storage, and heat release.

Transition Region Emission and the Energy Input to Thermal Plasma in Solar Flares

Science.gov (United States)

Holman, Gordon D.; Holman, Gordon D.; Dennis, Brian R.; Haga, Leah; Raymond, John C.; Panasyuk, Alexander

2005-01-01

Understanding the energetics of solar flares depends on obtaining reliable determinations of the energy input to flare plasma. X-ray observations of the thermal bremsstrahlung from hot flare plasma provide temperatures and emission measures which, along with estimates of the plasma volume, allow the energy content of this hot plasma to be computed. However, if thermal energy losses are significant or if significant energy goes directly into cooler plasma, this is only a lower limit on the total energy injected into thermal plasma during the flare. We use SOHO UVCS observations of O VI flare emission scattered by coronal O VI ions to deduce the flare emission at transition region temperatures between 100,000 K and 1 MK for the 2002 July 23 and other flares. We find that the radiated energy at these temperatures significantly increases the deduced energy input to the thermal plasma, but by an amount that is less than the uncertainty in the computed energies. Comparisons of computed thermal and nonthermal electron energies deduced from RHESSI, GOES, and UVCS are shown.

Cost and performance analysis of concentrating solar power systems with integrated latent thermal energy storage

International Nuclear Information System (INIS)

Nithyanandam, K.; Pitchumani, R.

2014-01-01

Integrating TES (thermal energy storage) in a CSP (concentrating solar power) plant allows for continuous operation even during times when solar irradiation is not available, thus providing a reliable output to the grid. In the present study, the cost and performance models of an EPCM-TES (encapsulated phase change material thermal energy storage) system and HP-TES (latent thermal storage system with embedded heat pipes) are integrated with a CSP power tower system model utilizing Rankine and s-CO 2 (supercritical carbon-dioxide) power conversion cycles, to investigate the dynamic TES-integrated plant performance. The influence of design parameters of the storage system on the performance of a 200 MW e capacity power tower CSP plant is studied to establish design envelopes that satisfy the U.S. Department of Energy SunShot Initiative requirements, which include a round-trip annualized exergetic efficiency greater than 95%, storage cost less than $15/kWh t and LCE (levelized cost of electricity) less than 6 ¢/kWh. From the design windows, optimum designs of the storage system based on minimum LCE, maximum exergetic efficiency, and maximum capacity factor are reported and compared with the results of two-tank molten salt storage system. Overall, the study presents the first effort to construct and analyze LTES (latent thermal energy storage) integrated CSP plant performance that can help assess the impact, cost and performance of LTES systems on power generation from molten salt power tower CSP plant. - Highlights: • Presents technoeconomic analysis of thermal energy storage integrated concentrating solar power plants. • Presents a comparison of different storage options. • Presents optimum design of thermal energy storage system for steam Rankine and supercritical carbon dioxide cycles. • Presents designs for maximizing exergetic efficiency while minimizing storage cost and levelized cost of energy

Investigation of solar parabolic trough power plants with and without integrated TES (thermal energy storage) and FBS (fuel backup system) using thermic oil and solar salt

International Nuclear Information System (INIS)

Boukelia, T.E.; Mecibah, M.S.; Kumar, B.N.; Reddy, K.S.

2015-01-01

Thermodynamic, economic and environmental analyses of concentrating solar power plants assist in identifying an effective and viable configuration. In this paper, a 4E (energy-exergy-environmental-economic) comparative study of 8 different configurations of parabolic trough solar thermal power plants with two different working fluids (Therminol VP-1 -oil and molten solar salt), with and without integrated thermal energy storage or/and backup fuel system is presented. The results of the comparative study indicate relevant differences among the 8 configurations. The molten solar salt configuration with integrated thermal energy storage and fossil fuel backup system exhibits the highest overall energy efficiency (18.48%) compared to other configurations. Whereas, the highest overall exergy efficiency (21.77%), capacity factor (38.20%) and annual energy generation (114 GWh) are found for the oil based configuration with integrated thermal energy storage and fossil fuel backup system. The results indicate that the configurations based on molten salt are better in terms of environmental and economical parameters. The configurations with integrated thermal energy storage and fossil fuel backup system are found to be techno-economical, but on the other hand are less environment friendly. A detailed comparison of these plants after optimization must be performed before drawing a final conclusion about the best configuration to be adopted in parabolic trough solar thermal power plant. - Highlights: • 4E comparative study of 8 configurations of PTSTPP with two different fluids. • Comparison of the configurations with and without integrated TES (thermal energy storage) and FBS (fuel backup system). • The overall energy efficiency of the salt plant with TES and FBS is the highest. • The overall exergy efficiency of the oil plant with TES and FBS is the highest. • The salt plants are the best configurations in terms of environ–eco parameters

Solar-thermal-energy collection/storage-pond system

Science.gov (United States)

Blahnik, D.E.

1982-03-25

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

Control of Solar Energy Systems

CERN Document Server

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

2012-01-01

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

Electrochemical energy storage systems for solar thermal applications

Science.gov (United States)

Krauthamer, S.; Frank, H.

1980-01-01

Existing and advanced electrochemical storage and inversion/conversion systems that may be used with terrestrial solar-thermal power systems are evaluated. The status, cost and performance of existing storage systems are assessed, and the cost, performance, and availability of advanced systems are projected. A prime consideration is the cost of delivered energy from plants utilizing electrochemical storage. Results indicate that the five most attractive electrochemical storage systems are the: iron-chromium redox (NASA LeRC), zinc-bromine (Exxon), sodium-sulfur (Ford), sodium-sulfur (Dow), and zinc-chlorine (EDA).

The development of a volumetric solar thermal receiver: an overview

International Nuclear Information System (INIS)

Sagie, D.

1996-01-01

Solar energy has received much interest in recent years, being a clean (free of pollution or other environmental damage) and inexhaustible energy source. It is also considered safer than some other non conventional energy sources (like nuclear energy). The interest in solar energy is motivated mainly by the growing awareness of the environmental problems associated with the use of conventional fuels. However, solar energy may become a serious alternative only if it can be used efficiently in major energy consuming industries (like the chemical industry), or be used for electricity generation. Those facilities are nowadays solely dependent on fossil fuels as the prime source of energy. The solar energy, reaching the earth in the form of radiation, can be utilized either by direct quantum conversion using photo-voltaic solar cells, or by converting the radiation into thermal energy, to be used directly for heating, or to feed a thermal to electric converting cycle. After three decades of huge spending on the development of photo-voltaic systems those devices are commercially competitive only on a very small energy scale, while solar thermal commercial applications are more attractive. Prominent examples are the domestic heating water receivers (direct thermal), and LUZ International electricity generation plants which are currently operated on a commercial basis, supplying 80 MWe per plant. Direct thermal exploitation of solar energy is naturally more efficient than converting to electricity, but is limited to specific applications and locations especially since thermal storage at high temperature is not commercially viable. Efficient electricity production at a competitive price is clearly the biggest opportunity for solar energy . (author)

The limits to solar thermal electricity

International Nuclear Information System (INIS)

Trainer, Ted

2014-01-01

The potential and limits of solar thermal power systems depend primarily on their capacity to meet electricity demand in mid-winter, and the associated cost, storage and other implications. Evidence on output and costs is analysed. Most attention is given to central receivers. Problems of low radiation levels, embodied energy costs, variability and storage are discussed and are found to set significant difficulties for large scale solar thermal supply in less than ideal latitudes and seasons. It is concluded that for solar thermal systems to meet a large fraction of anticipated global electricity demand in winter would involve prohibitive capital costs. - Highlights: • Output and capital cost data for various solar thermal technologies is examined. • Special attention is given to performance in winter. • Attention is also given to the effect of solar intermittency. • Implications for storage are considered. • It is concluded that there are significant limits to solar thermal power

An experimental study on energy generation with a photovoltaic (PV)-solar thermal hybrid system

International Nuclear Information System (INIS)

Erdil, Erzat; Ilkan, Mustafa; Egelioglu, Fuat

2008-01-01

A hybrid system, composed of a photovoltaic (PV) module and a solar thermal collector is constructed and tested for energy collection at a geographic location of Cyprus. Normally, it is required to install a PV system occupying an area of about 10 m 2 in order to produce electrical energy; 7 kWh/day, required by a typical household. In this experimental study, we used only two PV modules of area approximately 0.6 m 2 (i.e., 1.3x0.47 m 2 ) each. PV modules absorb a considerable amount of solar radiation that generate undesirable heat. This thermal energy, however, may be utilized in water pre-heating applications. The proposed hybrid system produces about 2.8 kWh thermal energy daily. Various attachments that are placed over the hybrid modules lead to a total of 11.5% loss in electrical energy generation. This loss, however, represents only 1% of the 7 kWh energy that is consumed by a typical household in northern Cyprus. The pay-back period for the modification is less than 2 years. The low investment cost and the relatively short pay-back period make this hybrid system economically attractive

Solar thermal electricity production. A building block for the energy turnaround?; Solarthermische Stromerzeugung. Ein Baustein fuer die Energiewende?

Energy Technology Data Exchange (ETDEWEB)

Pitz-Paal, Robert [Deutsches Zentrum fuer Luft- und Raumfahrt (DLR) e.V., Koeln (Germany). Inst. fuer Solarforschung

2012-12-15

Whereas in Germany enthusiasm for solar thermal power plants has subsided following the inglorious insolvency of Solar Millennium AG, internationally the market is livening up again. This has to do with the fact that many countries have now understood that security of supply cannot be founded on photovoltaics and wind alone in the long term. Solar thermal power could thus yet become an important building block in Germany's energy supply system as it continues to pursue the energy turnaround.

Solar thermal organic rankine cycle for micro-generation

Science.gov (United States)

Alkahli, N. A.; Abdullah, H.; Darus, A. N.; Jalaludin, A. F.

2012-06-01

The conceptual design of an Organic Rankine Cycle (ORC) driven by solar thermal energy is developed for the decentralized production of electricity of up to 50 kW. Conventional Rankine Cycle uses water as the working fluid whereas ORC uses organic compound as the working fluid and it is particularly suitable for low temperature applications. The ORC and the solar collector will be sized according to the solar flux distribution in the Republic of Yemen for the required power output of 50 kW. This will be a micro power generation system that consists of two cycles, the solar thermal cycle that harness solar energy and the power cycle, which is the ORC that generates electricity. As for the solar thermal cycle, heat transfer fluid (HTF) circulates the cycle while absorbing thermal energy from the sun through a parabolic trough collector and then storing it in a thermal storage to increase system efficiency and maintains system operation during low radiation. The heat is then transferred to the organic fluid in the ORC via a heat exchanger. The organic fluids to be used and analyzed in the ORC are hydrocarbons R600a and R290.

Dynamic modeling and sensitivity analysis of solar thermal energy conversion systems

Science.gov (United States)

Hamilton, C. L.

1977-01-01

Since the energy input to solar thermal conversion systems is both time variant and probabilistic, it is unlikely that simple steady-state methods for estimating lifetime performance will provide satisfactory results. The work described here uses dynamic modeling to begin identifying what must be known about input radiation and system dynamic characteristics to estimate performance reliably. Daily operation of two conceptual solar energy systems was simulated under varying operating strategies with time-dependent radiation intensity ranging from smooth input of several magnitudes to input of constant total energy whose intensity oscillated with periods from 1/4 hour to 6 hours. Integrated daily system output and efficiency were functions of both level and dynamic characteristics of insolation. Sensitivity of output to changes in total input was greater than one.

Solar energy conversion

Energy Technology Data Exchange (ETDEWEB)

Kistler, J.

1981-08-05

The photovoltaic generator is the central part of all solar systems. Flat solar cells embedded in glass are preferred which can also convert diffuse solar radiation. Hybrid modules generate electrical and thermal energy simultaneously. With decreasing generator cost, the cost of energy storage becomes critical. Development activities are mostly directed on the development of stationary lead accumulator batteries and the electronic charging and protective systems. The block diagram of the current converter is presented, and applications of solar systems in domestic heating engineering, transportation technology, communications, and hydrological engineering. Solar villages are recommended which, established in bilateral cooperation with Third World authorities, may demonstrate the advantages of solar energy in heat and electric power generation.

Experimental Evaluation of Simple Thermal Storage Control Strategies in Low-Energy Solar Houses to Reduce Electricity Consumption during Grid On-Peak Periods

Directory of Open Access Journals (Sweden)

Kyoung-Ho Lee

2015-08-01

Full Text Available There is growing interest in zero-energy and low-energy buildings, which have a net energy consumption (on an annual basis of almost zero. Because they can generate both electricity and thermal energy through the use of solar photovoltaic (PV and solar thermal collectors, and with the help of reduced building thermal demand, low-energy buildings can not only make a significant contribution to energy conservation on an annual basis, but also reduce energy consumption and peak demand. This study focused on electricity consumption during the on-peak period in a low-energy residential solar building and considers the use of a building’s thermal mass and thermal storage to reduce electricity consumption in summer and winter by modulation of temperature setpoints for heat pump and indoor thermostats in summer and additional use of a solar heating loop in winter. Experiments were performed at a low-energy solar demonstration house that has solar collectors, hot water storage, a ground-coupled heat pump, and a thermal storage tank. It was assumed that the on-peak periods were from 2 pm to 5 pm on hot summer days and from 5 pm to 8 pm on cold winter days. To evaluate the potential for utilizing the building’s thermal storage capacity in space cooling and heating, the use of simple control strategies on three test days in summer and two test days in the early spring were compared in terms of net electricity consumption and peak demand, which also considered the electricity generation from solar PV modules on the roof of the house.

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.

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

Energy Technology Data Exchange (ETDEWEB)

Glenn, Jaouen

2006-07-01

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

Hydrogen from solar energy

Energy Technology Data Exchange (ETDEWEB)

1977-04-01

The long-range options of energy sources are the breeding reactor, nuclear fusion, and solar energy. Concerning solar energy three systems are being developed: First the photovoltaic cells which are almost ready for industrial production, but which are still too expensive - at least today. Secondly the thermal utilization of solar radiation. Compared to these, thirdly, the photobiological and photochemical possibilities of solar energy utilization have been somewhat neglected so far. However, the photolysis of water by solar energy is a very promising option for future energy demands. This can be done by making use of the photo-synthetic splitting of water in technical facilities or with semiconductors.

Dish concentrators for solar thermal energy: Status and technology development

Science.gov (United States)

Jaffe, L. D.

1982-01-01

Point-focusing concentrators under consideration for solar thermal energy use are reviewed. These concentrators differ in such characteristics as optical configuration, optical materials, structure for support of the optical elements and of the receiver, mount, foundation, drive, controls and enclosure. Concentrator performance and cost are considered. Technology development is outlined, including wind loads and aerodynamics; precipitation, sand, and seismic considerations; and maintenance and cleaning.

A perspective of the market of thermal solar energy; Una perspectiva del mercado de la energia solar termica

Energy Technology Data Exchange (ETDEWEB)

Dominguez, R.; Moreno, J.

2008-07-01

The take in effect in 2006 of the new Technical Code of Edification (CTE) augured a remarkable impact in the market of the thermal solar energy in Spain. Parallelly, in april of this year was published in Portugal the Regulation of the Characteristics of thermal Behaviours of the Buildings (RCCTE) that also generated promising expectations. A year and a half later, the market does not match to the initial forecasts made by the government agencies and the solar industry. The purpose of this article is to make an analysis of the causes of ralentization in the definitive takeoff of both markets. (Author)

Solar energy enters the market

International Nuclear Information System (INIS)

Coehoorn, M.; Sinke, W.C.

1995-11-01

Everybody agrees that there is a bright future for solar energy. After two decades of research and development, the market introduction of solar hot water systems is now taking off. In several countries, including the Netherlands, preparations are also underway for the large-scale introduction of photovoltaic systems. Although the share of thermal and photovoltaic solar energy in the energy supply sector in the Netherlands is very small (0.1 PJ) there are signs of imminent change. According to the Follow-up Policy Document on Energy Conservation, the share of solar energy should increase to 7 PJ by the year 2010. After years of concentrating on research and development, it is now generally recognised that it is time to introduce these technologies onto the market in order to realize the long-term objectives. In this respect, thermal solar energy is ahead of photovoltaics. 4 ills

Solar Energy - An Option for Future Energy Production

Science.gov (United States)

Glaser, Peter E.

1972-01-01

Discusses the exponential growth of energy consumption and future consequences. Possible methods of converting solar energy to power such as direct energy conversion, focusing collectors, selective rediation absorbers, ocean thermal gradient, and space solar power are considered. (DF)

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

Science.gov (United States)

Longe, Karen M.; McClelland, Michael J.

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

Diaryl-substituted norbornadienes with red-shifted absorption for molecular solar thermal energy storage.

Science.gov (United States)

Gray, Victor; Lennartson, Anders; Ratanalert, Phasin; Börjesson, Karl; Moth-Poulsen, Kasper

2014-05-25

Red-shifting the absorption of norbornadienes (NBDs), into the visible region, enables the photo-isomerization of NBDs to quadricyclanes (QCs) to be driven by sunlight. This is necessary in order to utilize the NBD-QC system for molecular solar thermal (MOST) energy storage. Reported here is a study on five diaryl-substituted norbornadienes. The introduced aryl-groups induce a significant red-shift of the UV/vis absorption spectrum of the norbornadienes, and device experiments using a solar-simulator set-up demonstrate the potential use of these compounds for MOST energy storage.

Solar Energy: Its Technologies and Applications

Science.gov (United States)

Auh, P. C.

1978-06-01

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

Thermal analysis and design of passive solar buildings

CERN Document Server

Athienitis, AK

2013-01-01

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

Reports on 1979 result of Sunshine Project. Investigation and research on solar energy utilization system (solar thermal power generation system); 1979 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyonetsu hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1980-03-01

An investigation and research were conducted on the operation method of various solar thermal power generation systems and on the evaluation of the rating and cost performance; in the environmental test method for the equipment, the examination was continued for the test method and evaluation method concerning the absorbing surface and transmitting film; in the heat storing technology, an investigative research was done on the optimum heat storing method and energy conversion method suitable for the operation of the thermal power generation system, as well as performing, as an objective, a computer simulation on the total system with the purpose of clarifying the heat storing capacity. The results in the year were as follows. The operation method for solar thermal power generation was examined, as were the energy analysis, evaluation method of 1 MW pilot plant, the optimum utilization system of solar energy in the long run including its application, and technological economical problems to be solved for the next large solar thermal power generating plant. A discussion was carried out on the endurance test of the selective absorbing surface and transmitting film and on the durability of the reflection mirror. Evaluation and examination were made on the various materials of the 1 MW pilot plant. A review was done on various heat accumulating devices for solar thermal generation, mathematical thermal characteristics of heat accumulating devices, and future energy storing methods and problems. (NEDO)

Silicon Nanowires for Solar Thermal Energy Harvesting: an Experimental Evaluation on the Trade-off Effects of the Spectral Optical Properties.

Science.gov (United States)

Sekone, Abdoul Karim; Chen, Yu-Bin; Lu, Ming-Chang; Chen, Wen-Kai; Liu, Chia-An; Lee, Ming-Tsang

2016-12-01

Silicon nanowire possesses great potential as the material for renewable energy harvesting and conversion. The significantly reduced spectral reflectivity of silicon nanowire to visible light makes it even more attractive in solar energy applications. However, the benefit of its use for solar thermal energy harvesting remains to be investigated and has so far not been clearly reported. The purpose of this study is to provide practical information and insight into the performance of silicon nanowires in solar thermal energy conversion systems. Spectral hemispherical reflectivity and transmissivity of the black silicon nanowire array on silicon wafer substrate were measured. It was observed that the reflectivity is lower in the visible range but higher in the infrared range compared to the plain silicon wafer. A drying experiment and a theoretical calculation were carried out to directly evaluate the effects of the trade-off between scattering properties at different wavelengths. It is clearly seen that silicon nanowires can improve the solar thermal energy harnessing. The results showed that a 17.8 % increase in the harvest and utilization of solar thermal energy could be achieved using a silicon nanowire array on silicon substrate as compared to that obtained with a plain silicon wafer.

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

Directory of Open Access Journals (Sweden)

Asif Mahmood

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

Solar energy an introduction

CERN Document Server

Mackay, Michael E

2015-01-01

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

Solar energy; Product information. Zonne-energie; Produktinformatie

Energy Technology Data Exchange (ETDEWEB)

Kruisheer, N

1992-03-20

In five brief articles product information is given on solar energy applications with special attention to the Netherlands. After an introduction on solar energy availability in the Netherlands the developments in solar boiler techniques are dealt with. Solar water heaters have advantages for the environment, and government subsidies stimulate different uses of such water heaters. Also the developments of solar cells show good prospects, not only for developing countries, but also for the industrialized countries. In brief the developments in solar energy storage and the connection of solar equipment to the grid are discussed. Finally attention is paid to the applications of passive solar energy in the housing construction, the use of transparent thermal insulation and the developments of translucent materials. 18 figs., 18 ills.

Influence of accelerated thermal charging and discharging cycles on thermo-physical properties of organic phase change materials for solar thermal energy storage applications

International Nuclear Information System (INIS)

Raam Dheep, G.; Sreekumar, A.

2015-01-01

Highlights: • Identification of organic phase change materials namely benzamide and sebacic acid. • Thermal reliability studies on identified phase change materials. • Measurement of phase transition temperature and latent heat of fusion. • Analysis of relative percentage difference (RPD%) in heat of fusion and melting temperature of benzamide and sebacic acid. - Abstract: Integration of appropriate thermal energy storage system plays a predominant role in upgrading the efficiency of solar thermal energy devices by reducing the incongruity between energy supply and demand. Latent heat thermal energy storage based on phase change materials (PCM) is found to be the most efficient and prospective method for storage of solar thermal energy. Ensuring the thermal reliability of PCM through large number of charging (melting) and discharging (solidification) cycles is a primary prerequisite to determine the suitability of PCM for a specific thermal energy storage applications. The present study explains the experimental analysis carried out on two PCM’s namely benzamide and sebacic acid to check the compatibility of the material in solar thermal energy storage applications. The selected materials were subjected to one thousand accelerated melting and solidification cycles in order to investigate the percentage of variation at different stages on latent heat of fusion, phase transition temperature, onset and peak melting temperature. Differential Scanning Calorimeter (DSC) was used to determine the phase transition temperature and heat of fusion upon completion of every 100 thermal cycles and continued up to 1000 cycles. Relative Percentage Difference (RPD%) is calculated to find out the absolute deviation of melting temperature and latent heat of fusion with respect to zeroth cycle. The experimental study recorded a melting temperatures of benzamide and sebacic acid as 125.09 °C and 135.92 °C with latent heat of fusion of 285.1 (J/g) and 374.4 (J/g). The

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

Solar thermal energy as a topic in secondary mathematics classrooms

Energy Technology Data Exchange (ETDEWEB)

Brinkmann, A.; Brinkmann, K. [EnviPro Environmental Process Engineering Prof. Dr. Klaus Brinkmann, Iserlohn (Germany)

2004-07-01

One of the most effective methods to achieve a sustainable change of our momentary existing power supply system to a system mainly based on renewable energy conversion is the education of our children. For this purpose the compulsory school subject mathematics appears to be suitable. In order to promote renewable energy issues in mathematics classrooms, the authors have developed a special didactical concept to open this field for students, as well as for their teachers. The aim of this paper is to present firstly an overview of our concept and secondly examples of problems to the special topic of solar thermal energy, developed on the basis of our concept. (orig.)

Proceedings of the IASTED international conference on solar energy : SOE 2009

Energy Technology Data Exchange (ETDEWEB)

Hamza, M.H. [International Association of Science and Technology for Development, Calgary, AB (Canada)] (ed.)

2009-07-01

This solar energy conference was attended by international researchers and practitioners working with leading edge solar energy technology as well as related areas such as renewable energy and clean energy. The topics of discussion included nanotechnologies for solar energy; photovoltaic energy; solar fuel cells; solar-powered vehicles; solar thermal energy; thin film batteries; desalination systems; solar cooling; clean energy; renewable energy; biomass energy; sustainability; flexible solar cells; hybrid power generation; organic solar cells; remote sensing of solar radiation; solar thermal conversion; sustainable buildings; and thin film silicon solar cells. Some of the presentations discussed the application of solar energy in agriculture, environment, economics and home construction. The sessions were entitled: grid connection and energy conversion; photovoltaic and nanotechnology; solar energy and applications; and solar thermal energy. Seventeen of the 18 presentations have been catalogued separately for inclusion in this database.

CURRENT TRENDS IN THE USE OF SOLAR ENERGY

OpenAIRE

Vanya Zhivkova

2013-01-01

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

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.

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.

CURRENT TRENDS IN THE USE OF SOLAR ENERGY

Directory of Open Access Journals (Sweden)

Vanya Zhivkova

2013-06-01

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

Solar thermal heating and cooling. A bibliography with abstracts

Science.gov (United States)

Arenson, M.

1979-01-01

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

Solar energy in Amersfoort, Netherlands

International Nuclear Information System (INIS)

Eijpe, H.A.

1997-01-01

For the first time in the world a newly to be built housing area (Nieuwland in Amersfoort, Netherlands) will be constructed, exclusively on the basis of sustainability. First, the use of three forms of solar energy conversion techniques (thermal solar energy, passive solar energy and photovoltaic energy) is going to be integrated in 50 rental houses. At the end of this century 10,000 m 2 of solar cells will be installed with a capacity of 1 MWp. 2 figs

Intelligent trend analysis for a solar thermal energy collector field

Science.gov (United States)

Juuso, E. K.

2018-03-01

Solar thermal power plants collect available solar energy in a usable form at a temperature range which is adapted to the irradiation levels and seasonal variations. Solar energy can be collected only when the irradiation is high enough to produce the required temperatures. During the operation, a trade-off of the temperature and the flow is needed to achieve a good level for the collected power. The scaling approach brings temporal analysis to all measurements and features: trend indices are calculated by comparing the averages in the long and short time windows, a weighted sum of the trend index and its derivative detects the trend episodes and severity of the trend is estimated by including also the variable level in the sum. The trend index, trend episodes and especially, the deviation index reveal early evolving changes in the operating conditions, including cloudiness and load disturbances. The solution is highly compact: all variables, features and indices are transformed to the range [-2, 2] and represented in natural language which is important in integrating data-driven solutions with domain expertise. The special situations detected during the test campaigns are explained well.

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.

Conversion of concentrated solar thermal energy into chemical energy.

Science.gov (United States)

Tamaura, Yutaka

2012-01-01

When a concentrated solar beam is irradiated to the ceramics such as Ni-ferrite, the high-energy flux in the range of 1500-2500 kW/m(2) is absorbed by an excess Frenkel defect formation. This non-equilibrium state defect is generated not by heating at a low heating-rate (30 K/min), but by irradiating high flux energy of concentrated solar beam rapidly at a high heating rate (200 K/min). The defect can be spontaneously converted to chemical energy of a cation-excess spinel structure (reduced-oxide form) at the temperature around 1773 K. Thus, the O(2) releasing reaction (α-O(2) releasing reaction) proceeds in two-steps; (1) high flux energy of concentrated solar beam absorption by formation of the non-equilibrium Frenkel defect and (2) the O(2) gas formation from the O(2-) in the Frenkel defect even in air atmosphere. The 2nd step proceeds without the solar radiation. We may say that the 1st step is light reaction, and 2nd step, dark reaction, just like in photosynthesis process.

Solar-assisted low energy dwellings

Energy Technology Data Exchange (ETDEWEB)

Esbensen, T V

1980-02-01

The Zero Energy House Group was formed as a subproject of the CCMS Solar Energy Pilot Study in 1974 by seven participating countries experimenting with solar-assisted low-energy dwellings for temperate and northern European climatic conditions. A Zero Energy House is one in which solar energy is used to meet the reduced energy needs of buildings incorporating various thermal energy conservation features. This final report of the Zero Energy House Group includes brief descriptions of 13 major low-energy dwellings in the participating CCMS countries. An overall assessment of the state-of-the-art in solar-assisted low-energy dwellings is also included.

Performance of a combined cooling heating and power system with mid-and-low temperature solar thermal energy and methanol decomposition integration

International Nuclear Information System (INIS)

Xu, Da; Liu, Qibin; Lei, Jing; Jin, Hongguang

2015-01-01

Highlights: • A new middle-and-low temperature solar thermochemical CCHP system is proposed. • The thermodynamic performances of the new system are numerically evaluated. • The superiorities of the new system are demonstrated. - Abstract: In this paper, a new distributed energy system that integrates the mid-and-low temperature solar energy thermochemical process and the methanol decomposition is proposed. Through the solar energy receiver/reactor, the energy collected by a parabolic trough concentrator, at 200–300 °C, is used to drive the decomposition reaction of the methanol into the synthesis gas, and thus the solar thermal energy is converted to the chemical energy. The chemical energy of the synthesis gas released in the combustion chamber of a micro gas turbine is used to drive the combined cooling heating and power systems. Energy analysis and exergy analysis of the system are implemented to evaluate the feasibility of the proposed system. Under the considerations of the changes of the solar irradiation intensity, the off-design performances of the micro turbine and the variations of the load, the design and off-design thermodynamic performances of the system and the characteristics of the chemical energy storage are numerically studied. Numerical results indicate that the primary energy ratio of the system is 76.40%, and the net solar-electricity conversion rate reaches 22.56%, which is higher than exiting large-scale solar thermal power plants. Owing to the introduction of a the solar thermochemical energy storage in the proposed system, the power generation efficiency is insensitive to the variations of the solar radiation, and thus an efficient and stable utilization approach of the solar thermal energy is achieved at all work condition

Inventory of thermal solar energy systems in the Netherlands: Period 1975-1992

International Nuclear Information System (INIS)

Warmerdam, J.M.; Stap, C.A.M.

1993-10-01

An overview is given of the number of active thermal solar energy systems that have been installed in the Netherlands during the period 1975-1992. By the end of 1992, 8,300 systems have been installed, of which 6,000 were domestic solar hot water systems. The uncertainty in these figures is 10%. Several sources were used to determine the number of systems installed. The two main sources were the files of the solar industry association 'Holland Solar' (data until 1988), and the Dutch subsidy administrator 'Senter' for data from 1988 up to and including 1992. At the end of 1992 preparations were made for the installation of approximately 3,000 domestic solar water heaters in 1993. It is recommended to carry out an inventory every three months and to compile data on investment costs. 17 figs., 7 appendices

Evaluation of in-situ thermal energy storage for lunar based solar dynamic systems

Science.gov (United States)

Crane, Roger A.

1991-01-01

A practical lunar based thermal energy storage system, based on locally available materials, could significantly reduce transportation requirements and associated costs of a continuous, solar derived power system. The concept reported here is based on a unique, in-situ approach to thermal energy storage. The proposed design is examined to assess the problems of start-up and the requirements for attainment of stable operation. The design remains, at this stage, partially conceptional in nature, but certain aspects of the design, bearing directly on feasibility, are examined in some detail. Specifically included is an engineering evaluation of the projected thermal performance of this system. Both steady state and start-up power requirements are evaluated and the associated thermal losses are evaluated as a basis for establishing potential system performance.

A novel syngas-fired hybrid heating source for solar-thermal applications: Energy and exergy analysis

International Nuclear Information System (INIS)

Pramanik, Santanu; Ravikrishna, R.V.

2016-01-01

Highlights: • Biomass-derived syngas as a hybrid energy source for solar thermal power plants. • A novel combustor concept using rich-catalytic and MILD combustion technologies. • Hybrid energy source for a solar-driven supercritical CO 2 -based Brayton cycle. • Comprehensive energetic and exergetic analysis of the combined system. - Abstract: A hybrid heating source using biomass-derived syngas is proposed to enable continuous operation of standalone solar thermal power generation plants. A novel, two-stage, low temperature combustion system is proposed that has the potential to provide stable combustion of syngas with near-zero NO x emissions. The hybrid heating system consists of a downdraft gasifier, a two-stage combustion system, and other auxiliaries. When integrated with a solar cycle, the entire system can be referred to as the integrated gasification solar combined cycle (IGSCC). The supercritical CO 2 Brayton cycle (SCO 2 ) is selected for the solar cycle due to its high efficiency. The thermodynamic performance evaluation of the individual unit and the combined system has been conducted from both energy and exergy considerations. The effect of parameters such as gasification temperature, biomass moisture content, equivalence ratio, and pressure ratio is studied. The efficiency of the IGSCC exhibited a non-monotonic behavior. A maximum thermal efficiency of 36.5% was achieved at an overall equivalence ratio of 0.22 and pressure ratio of 2.75 when the gasifier was operating at T g = 1073 K with biomass containing 20% moisture. The efficiency increased to 40.8% when dry biomass was gasified at a temperature of 973 K. The exergy analysis revealed that the maximum exergy destruction occurred in the gasification system, followed by the combustion system, SCO 2 cycle, and regenerator. The exergy analysis also showed that 8.72% of the total exergy is lost in the exhaust; however, this can be utilized for drying of the biomass.

Microgrid Control Strategy Utlizing Thermal Energy Storage With Renewable Solar And Wind Power Generation

Science.gov (United States)

2016-06-01

iii Approved for public release; distribution is unlimited MICROGRID CONTROL STRATEGY UTLIZING THERMAL ENERGY STORAGE WITH RENEWABLE SOLAR AND WIND... control tracks increasing power generation in the morning. The batteries require a large amount of electrical power to charge every morning, as charge ...is 37 lost throughout the night. This causes the solar panels to output their maximum power generation. The MPPT control records when power

SOLAR ENERGY POLICY DEVELOPMENTS IN EUROPE

OpenAIRE

Mihaela PÃCE?ILÃ

2015-01-01

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

Value and cost analyses for solar thermal-storage systems

Energy Technology Data Exchange (ETDEWEB)

Luft, W.; Copeland, R.J.

1983-04-01

Value and cost data for thermal energy storage are presented for solar thermal central receiver systems for which thermal energy storage appears to be attractive. Both solar thermal electric power and industrial process heat applications are evaluated. The value of storage is based on the cost for fossil fuel and solar thermal collector systems in 1990. The costing uses a standard lifetime methodology with the storage capacity as a parameter. Both value and costs are functions of storage capacity. However, the value function depends on the application. Value/cost analyses for first-generation storage concepts for five central receiver systems (molten salt, water/steam, organic fluid, air, and liquid metal) established the reference against which new systems were compared. Some promising second-generation energy storage concepts have been identified, and some more advanced concepts have also been evaluated.

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.

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

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

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

Solar thermal electricity generation

Science.gov (United States)

Gasemagha, Khairy Ramadan

1993-01-01

This report presents the results of modeling the thermal performance and economic feasibility of large (utility scale) and small solar thermal power plants for electricity generation. A number of solar concepts for power systems applications have been investigated. Each concept has been analyzed over a range of plant power ratings from 1 MW(sub e) to 300 MW(sub e) and over a range of capacity factors from a no-storage case (capacity factor of about 0.25 to 0.30) up to intermediate load capacity factors in the range of 0.46 to 0.60. The solar plant's economic viability is investigated by examining the effect of various parameters on the plant costs (both capital and O & M) and the levelized energy costs (LEC). The cost components are reported in six categories: collectors, energy transport, energy storage, energy conversion, balance of plant, and indirect/contingency costs. Concentrator and receiver costs are included in the collector category. Thermal and electric energy transport costs are included in the energy transport category. Costs for the thermal or electric storage are included in the energy storage category; energy conversion costs are included in the energy conversion category. The balance of plant cost category comprises the structures, land, service facilities, power conditioning, instrumentation and controls, and spare part costs. The indirect/contingency category consists of the indirect construction and the contingency costs. The concepts included in the study are (1) molten salt cavity central receiver with salt storage (PFCR/R-C-Salt); (2) molten salt external central receiver with salt storage (PFCR/R-E-Salt); (3) sodium external central receiver with sodium storage (PFCR/RE-Na); (4) sodium external central receiver with salt storage (PFCR/R-E-Na/Salt); (5) water/steam external central receiver with oil/rock storage (PFCR/R-E-W/S); (6) parabolic dish with stirling engine conversion and lead acid battery storage (PFDR/SLAB); (7) parabolic dish

The performance of a novel flat heat pipe based thermal and PV/T (photovoltaic and thermal systems) solar collector that can be used as an energy-active building envelope material

International Nuclear Information System (INIS)

Jouhara, H.; Milko, J.; Danielewicz, J.; Sayegh, M.A.; Szulgowska-Zgrzywa, M.; Ramos, J.B.; Lester, S.P.

2016-01-01

A novel flat heat pipe design has been developed and utilised as a building envelope and thermal solar collector with and without (PV) bonded directly to its surface. The design of the new solar collector has been validated through full scale testing in Cardiff, UK where solar/thermal, uncooled PV and PV/T tests were carried out on three identical systems, simultaneously. The tests showed a solar/thermal energy conversion efficiency of around 64% for the collector with no PV and 50% for the system with the PV layer on it. The effect of cooling on the solar/electrical energy conversion efficiency was also investigated and an efficiency increase of about 15% was recorded for the cooled PV system due to the provided homogenous cooling. The new flat heat pipe solar collector is given the name “heat mat” and, in addition to being an efficient solar collector type, it is also designed to convert a building envelope materials to become energy-active. A full size roof that utilise this new building envelope material is reported in this paper to demonstrate the way this new collector is integrated as a building envelope material to form a roof. A thermal absorption test, in a controlled environment, from the ambient to the heat mat with no solar radiation is also reported. The test has proved the heat mat as an efficient thermal absorber from the ambient to the intermediate fluid that deliver the heat energy to the heat pump system. - Highlights: • A new flat heat pipe PV/T system that can be used as building materials is reported. • The new solar collector enhanced the performance of the PV by about 15%. • The new solar collector is capable of absorbing heat from ambient efficiently. • The new system is efficient from the solar/thermal conversion point of view.

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

Energy Technology Data Exchange (ETDEWEB)

1985-01-01

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

Performance analysis of a lunar based solar thermal power system with regolith thermal storage

International Nuclear Information System (INIS)

Lu, Xiaochen; Ma, Rong; Wang, Chao; Yao, Wei

2016-01-01

The manned deep-space exploration is a hot topic of the current space activities. The continuous supply of thermal and electrical energy for the scientific equipment and human beings is a crucial issue for the lunar outposts. Since the night lasts for periods of about 350 h at most locations on the lunar surface, massive energy storage is required for continuous energy supply during the lengthy lunar night and the in-situ resource utilization is demanded. A lunar based solar thermal power system with regolith thermal storage is presented in this paper. The performance analysis is carried out by the finite-time thermodynamics to take into account major irreversible losses. The influences of some key design parameters are analyzed for system optimization. The analytical results shows that the lunar based solar thermal power system with regolith thermal storage can meet the requirement of the continuous energy supply for lunar outposts. - Highlights: • A lunar based solar thermal power system with regolith thermal storage is presented. • The performance analysis is carried out by the finite-time thermodynamics. • The influences of some key design parameters are analyzed.

Solar thermal in France

International Nuclear Information System (INIS)

Letz, T.

2006-01-01

This article gives details of Plan Soleil established in 2000 by the French Agency for Environment and Energy Management and its identification of solar hot water systems and combined domestic solar hot water and space heating as promising sectors for development. The setting up of a support scheme for investment by Plan Soleil is discussed along with subsidies and grants, manufacturers and importers, the guarantee of solar results, and the quality of plants, components, and installers. The costs of thermal solar equipment, and results of the French assessment programme are considered. The need for quality standards is stressed

Thermal performance of evacuated tube heat pipe solar collector

Science.gov (United States)

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

2016-06-01

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

Confinement of solar thermal energy by Nesa film; Nesa maku ni yoru taiyo netsu energy no fujikome

Energy Technology Data Exchange (ETDEWEB)

Shimizu, A; Yano, K; Kasuga, M; Daigo, Y [Yamanashi University, Yamanashi (Japan). Faculty of Engineering

1997-11-25

This paper reports a Nesa (SnO2) film as selective transmissive film for effective confinement of solar thermal energy. Solar light spectrum ranges from 0.3 to 2.0{mu}m, while thermal radiation from bodies at 100-200degC is infrared ray more than 2{mu}m. Consequently, a solar water heater using the film which can pass rays below 2.0{mu}m while reflect rays over 2.0{mu}m for windows is very efficient. The Nesa film reflects rays with wavelengths more than plasma wavelengths (controllable from 1 to several {mu}m) by plasma action of free electrons. The Nesa films with different carrier densities were fabricated by spraying deposition method at dopant rates (Sb/Sn) from 0 to 2mol%. The solar water heaters were prepared using normal glass and specific glass coated with the Nesa film as selective transmissive film. The heater using the glass coated with the Nesa film of 2{mu}m plasma wavelength for windows could efficiently confine solar heat. The Nesa film of 700nm plasma wavelength which can pass visible light while reflect infrared ray was effective to reduce cooling/heating losses. 3 refs., 6 figs.

Nonimaging concentrators for solar thermal energy

Science.gov (United States)

Winston, R.; Gallagher, J. J.

1980-03-01

A small experimental solar collector test facility was used to explore applications of nonimaging optics for solar thermal concentration in three substantially different configurations: a single stage system with moderate concentration on an evacuated absorber (a 5.25X evacuated tube Compound Parabolic Concentrator or CPC), a two stage system with high concentration and a non-evacuated absorber (a 16X Fresnel lens/CPC type mirror) and moderate concentration single stage systems with non-evacuated absorbers for lower temperature (a 3X and a 6.5X CPC). Prototypes of each of these systems were designed, built and tested. The performance characteristics are presented.

Review and summary of Solar Thermal Conversion Program planning assistance

Energy Technology Data Exchange (ETDEWEB)

1975-06-01

The Solar Thermal Conversion Program comprises a major part of the national solar energy program which must be continuously reviewed and modified where necessary. Modifications are typically required to reflect technical achievements and uncertainties which arise from within the program or from other technical programs, changes in budgets available for supporting the program as well as internal program funding priorities, changing goals such as through acceleration or stretch-out of the program schedule, significant organizational changes involving responsible governmental agencies, the introduction of new project management support contractors, and required budget or schedule changes occurring within individual projects that make up the Solar Thermal Conversion Program. The Aerospace Corporation has provided data to assist in planning, review, coordination, and documentation of the overall Solar Thermal Conversion Program. The Solar Thermal Conversion Program Plan is described in detail. Sections 2.0 through 5.0 cover the discussion and detail planning covering the objectives, justification, basic and alternative plans, budgets, and schedules for the Solar Thermal sub-unit portion of the Solar Electric Applications effort. Appendices B1, B2, and B3 include the March 21, March 28, and April 5, 1975, Program Plan submissions of the complete Solar Electric Applications effort. In Appendix B the Solar Thermal, Solar Photovoltaic, Wind Energy, and Ocean Thermal sub-unit texts have been condensed and formatted for integration in the overall ERDA budget package. (WHK)

Solar thermal technology report, FY 1981. Volume 1: Executive summary

Science.gov (United States)

1982-01-01

The activities of the Department of Energy's Solar Thermal Technology Program are discussed. Highlights of technical activities and brief descriptions of each technology are given. Solar thermal conversion concepts are discussed in detail, particularily concentrating collectors and salt-gradient solar ponds.

Full-spectrum volumetric solar thermal conversion via photonic nanofluids.

Science.gov (United States)

Liu, Xianglei; Xuan, Yimin

2017-10-12

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

Profits or preferences? Assessing the adoption of residential solar thermal technologies

International Nuclear Information System (INIS)

Mills, Bradford F.; Schleich, Joachim

2009-01-01

Solar thermal technologies offer the potential to meet a substantial share of residential water and space heating needs in the EU, but current levels of adoption are low. This paper uses data from a large sample of German households to assess the effects of geographic, residence, and household characteristics on the adoption of solar thermal water and space heating technologies. In addition, the impact of solar thermal technology adoption on household energy expenditures is estimated after controlling for observed household heterogeneity in geographic, residential, and household characteristics. While evidence is found of moderate household energy expenditure savings from combined solar water and space heating systems, the findings generally confirm that low in-home energy cost savings and fixed housing stocks limit the diffusion of residential solar thermal technologies. Little evidence is found of differential adoption by distinct socio-economic groups.

Thermal performance analysis of a solar heating plant

DEFF Research Database (Denmark)

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

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

Solar cooling between thermal and photovoltaic: An energy and economic comparative study in the Mediterranean conditions

International Nuclear Information System (INIS)

Noro, M.; Lazzarin, R.M.

2014-01-01

This paper considers different cooling systems and investigates the most promising alternatives when solar energy is to be used to supply the cooling demand. All the systems are evaluated during a summer cooling season by the energetic and economic point of view by dynamic simulation for two different climates. For Milan (Cfb climate) the highest OSE (overall system efficiency) is reached by LiBr (lithium-bromide) double effect absorption chiller driven by parabolic through collector (0.53). In terms of the collecting surface area, the best systems for Milan feature 0.08 m 2  MJ −1 per day both for electric system (mono-crystalline photovoltaic coupled to water cooled chiller) and thermal system (PTC (parabolic trough collectors) coupled to double effect water-LiBr absorption chiller). Southern latitudes like Trapani (Csa climate) allow a quite better performance for thermal solar cooling solutions. The NPV (net present worths) of electric solar cooling solutions are favorable with respect to the traditional solution and the DPV (discounted payback periods) are all lower than the period of economic analysis above all for water cooled chillers. Finally a sensitivity analysis of the specific investment cost (€ MJ −1 per day) is carried out regarding the investment cost of collectors, the solar ratio and the interest rate. - Highlights: • Solar cooling is obtained with solar thermal or PV (photovoltaic) with easy available equipment. • In the past PV driven systems for solar cooling were not considered as too expensive. • An energy/economic comparison is carried out for the various solar cooling systems. • Sensitivity analyses are carried out varying different parameters

Solar thermal collectors at design and technology activity days

OpenAIRE

Petrina, Darinka

2016-01-01

Thesis encompases usage of renewable resources of energy, especially solar energy, which is essential for our future. On one hand, certain ways of exploiting solar energy (with solar cells) have been well established and is included in the Design and technology curriculum, on the other hand however, solar thermal collectors have not been recognized enough in spite of their distribution, applicability and environmentally friendly technology. Consequently thesis emphasizes the usage of solar en...

Solar energy in Germany: a national commitment

International Nuclear Information System (INIS)

Persem, Melanie

2012-01-01

This document presents some key information and figures about the development of solar energy in Germany: national energy plan and share of solar energy in the German energy mix, the photovoltaic industry: a dynamic industry which creates jobs, 2006-2012 evolution of photovoltaic power plant costs, solar thermal resource potentialities and effective exploitation

Passive Solar Techniques to Improve Thermal Comfort and Reduce Energy Consumption of Domestic Use

OpenAIRE

Naci Kalkan; Ihsan Dagtekin

2016-01-01

Passive design responds to improve indoor thermal comfort and minimize the energy consumption. The present research analyzed the how efficiently passive solar technologies generate heating and cooling and provide the system integration for domestic applications. In addition to this, the aim of this study is to increase the efficiency of solar systems system with integration some innovation and optimization. As a result, outputs of the project might start a new sector to provide environmentall...

A Comprehensive Review of Thermal Energy Storage

Directory of Open Access Journals (Sweden)

Ioan Sarbu

2018-01-01

Full Text Available Thermal energy storage (TES is a technology that stocks thermal energy by heating or cooling a storage medium so that the stored energy can be used at a later time for heating and cooling applications and power generation. TES systems are used particularly in buildings and in industrial processes. This paper is focused on TES technologies that provide a way of valorizing solar heat and reducing the energy demand of buildings. The principles of several energy storage methods and calculation of storage capacities are described. Sensible heat storage technologies, including water tank, underground, and packed-bed storage methods, are briefly reviewed. Additionally, latent-heat storage systems associated with phase-change materials for use in solar heating/cooling of buildings, solar water heating, heat-pump systems, and concentrating solar power plants as well as thermo-chemical storage are discussed. Finally, cool thermal energy storage is also briefly reviewed and outstanding information on the performance and costs of TES systems are included.

Essential oil extraction with concentrating solar thermal energy

OpenAIRE

Veynandt, François

2015-01-01

Material complementari del cas estudi "Essential oil extraction with concentrating solar thermal energy”, part component del llibre "Case studies for developing globally responsible engineers" Peer Reviewed

Interplanetary ions during an energetic storm particle event: The distribution function from solar wind thermal energies to 1.6 MeV

International Nuclear Information System (INIS)

Gosling, J.T.; Asbridge, J.R.; Bame, S.J.; Feldman, W.C.; Zwickl, R.D.; Paschmann, G.; Sckopke, N.; Hynds, R.J.

1981-01-01

Data from the Los Alamos Scientific Laboratory/Max-Planck-Institut fast plasma experiment on Isee 2 have been combined with data from the European Space Agency/Imperial College/Space Research Laboratory low-energy proton experiment on Isee 3 to obtain for the first time an ion velocity distribution function f(v) extending from solar wind energies (-1 keV) to 1.6 MeV during the postshock phase of an energetic storm particle (ESP) event. This study reveals that f(v) of the ESP population is roughly isotropic in the solar wind frame from solar wind thermal energies out to 1.6 MeV. Emerging smoothly out of the solar wind thermal distribution, the ESP f(v) initially falls with increasing energy as E/sup -2.4/ in the solar wind frame. Above about 40 keV no single power law exponent adequately describes the energy dependence of f(v) in the solar wind frame. Above approx.200 keV in both the spacecraft frame and the solar wind frame, f(v) can be described by an exponential in speed (f(v)proportionale/sup -v/v//sub o/) with v/sub o/ = 1.05 x 10 8 cm s -1 . The ESP event studied (August 27, 1978) was superposed upon a more energetic particle event which was predominantly field-aligned and which was probably of solar origin. Our observations suggest that the ESP population is accelerated directly out of the solar wind thermal population or its quiescent suprathermal tail by a stochastic process associated with the shock wave disturbance. The acceleration mechanism is sufficiently efficient that approx.1% of the solar wind population is accelerated to suprathermal energies. These suprathermal particles have an energy density of approx.290 eV cm -3

Thermal energy storage for organic Rankine cycle solar dynamic space power systems

Science.gov (United States)

Heidenreich, G. R.; Parekh, M. B.

An organic Rankine cycle-solar dynamic power system (ORC-SDPS) comprises a concentrator, a radiator, a power conversion unit, and a receiver with a thermal energy storage (TES) subsystem which charges and discharges energy to meet power demands during orbital insolation and eclipse periods. Attention is presently given to the criteria used in designing and evaluating an ORC-SDPS TES, as well as the automated test facility employed. It is found that a substantial data base exists for the design of an ORC-SDPS TES subsystem.

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

Science.gov (United States)

Ganesh, S; Arumugam, S

2016-12-01

The thermal performance of a shallow solar pond with and without the single transparent glass cover has been investigated experimentally. This experiment has been performed during the summer season of 2014 under the operational condition for five different storage volumes of water upto a maximum of 10liter. The pond performance is investigated in terms of the rate of energy collected and its collection efficiency. A Low Density Polyethylene (LDPE) black sheet liner of 200μm thickness was laid on all the interior sides of the pond for solar energy absorption. A clear transparent PVC plastic sheet of 150μm thickness was laid over the water surface as evaporation suppressing membrane. Calibrated Copper constantan thermocouples were used to measure the temperatures of the system. A highest temperature of 81.5°C has been achieved for the stored volume of 2liter of water, when the pond was used with a single transparent glass cover of 5mm thickness. When the shallow solar pond was used without the transparent glass cover the system attained a maximum temperature of 62°C for the same stored volume of 2liter. A comparison between the two conditions of with and without the transparent glass cover, on the thermal performance of the SSP has been reported. A shallow solar pond system of the present type could be used us a source of warm water, of desired temperature, below 10°C which are required for the domestic and industrial utilities. The global warming is increased day by day; inorder to reduce global warming a typical method of small scale shallow solar pond has been used to absorb the radiation from the sun to convert it to useful heat energy by the source of water. The SSP is an eco friendly way to generate energy without polluting our environment and in an environment safety manner. Based on environmental safety this study has experimentally investigated the thermal performance of the shallow solar pond. Copyright © 2016 Elsevier Inc. All rights reserved.

Promotion of solar thermal energy - guide and comparison of experience

Energy Technology Data Exchange (ETDEWEB)

Ballot, E [ALTER Alsace (France)

2004-01-01

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

Mechanism of Thermal Reversal of the (Fulvalene)tetracarbonyldiruthenium Photoisomerization: Toward Molecular Solar-Thermal Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Kanai, Y; Srinivasan, V; Meier, S K; Vollhardt, K P; Grossman, J C

2010-02-18

In the currently intensifying quest to harness solar energy for the powering of our planet, most efforts are centered around photoinduced generic charge separation, such as in photovoltaics, water splitting, other small molecule activation, and biologically inspired photosynthetic systems. In contrast, direct collection of heat from sunlight has received much less diversified attention, its bulk devoted to the development of concentrating solar thermal power plants, in which mirrors are used to focus the sun beam on an appropriate heat transfer material. An attractive alternative strategy would be to trap solar energy in the form of chemical bonds, ideally through the photoconversion of a suitable molecule to a higher energy isomer, which, in turn, would release the stored energy by thermal reversal. Such a system would encompass the essential elements of a rechargeable heat battery, with its inherent advantages of storage, transportability, and use on demand. The underlying concept has been explored extensively with organic molecules (such as the norbornadiene-quadricyclane cycle), often in the context of developing photoswitches. On the other hand, organometallic complexes have remained relatively obscure in this capacity, despite a number of advantages, including expanded structural tunability and generally favorable electronic absorption regimes. A highly promising organometallic system is the previously reported, robust photo-thermal fulvalene (Fv) diruthenium couple 1 {l_reversible} 2 (Scheme 1). However, although reversible and moderately efficient, lack of a full, detailed atom-scale understanding of its key conversion and storage mechanisms have limited our ability to improve on its performance or identify optimal variants, such as substituents on the Fv, ligands other than CO, and alternative metals. Here we present a theoretical investigation, in conjunction with corroborating experiments, of the mechanism for the heat releasing step of 2 {yields} 1 and

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

Science.gov (United States)

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

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

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)

Energy efficiency and comfort conditions in passive solar buildings: Effect of thermal mass at equatorial high altitudes

Science.gov (United States)

Ogoli, David Mwale

This dissertation is based on the philosophy that architectural design should not just be a function of aesthetics, but also of energy-efficiency, advanced technologies and passive solar strategies. A lot of published literature is silent regarding buildings in equatorial highland regions. This dissertation is part of the body of knowledge that attempts to provide a study of energy in buildings using thermal mass. The objectives were to establish (1) effect of equatorial high-altitude climate on thermal mass, (2) effect of thermal mass on moderating indoor temperatures, (3) effect of thermal mass in reducing heating and cooling energy, and (4) the amount of time lag and decrement factor of thermal mass. Evidence to analyze the effect of thermal mass issues came from three sources. First, experimental physical models involving four houses were parametrically conducted in Nairobi, Kenya. Second, energy computations were made using variations in thermal mass for determining annual energy usage and costs. Third, the data gathered were observed, evaluated, and compared with currently published research. The findings showed that: (1) Equatorial high-altitude climates that have diurnal temperature ranging about 10--15°C allow thermal mass to moderate indoor temperatures; (2) Several equations were established that indicate that indoor mean radiant temperatures can be predicted from outdoor temperatures; (3) Thermal mass can reduce annual energy for heating and cooling by about 71%; (4) Time lag and decrement of 200mm thick stone and concrete thermal mass can be predicted by a new formula; (5) All windows on a building should be shaded. East and west windows when shaded save 51% of the cooling energy. North and south windows when fully shaded account for a further 26% of the cooling energy; (6) Insulation on the outside of a wall reduces energy use by about 19.6% below the levels with insulation on the inside. The basic premise of this dissertation is that decisions that

Thermal photovoltaic solar integrated system analysis using neural networks

Energy Technology Data Exchange (ETDEWEB)

Ashhab, S. [Hashemite Univ., Zarqa (Jordan). Dept. of Mechanical Engineering

2007-07-01

The energy demand in Jordan is primarily met by petroleum products. As such, the development of renewable energy systems is quite attractive. In particular, solar energy is a promising renewable energy source in Jordan and has been used for food canning, paper production, air-conditioning and sterilization. Artificial neural networks (ANNs) have received significant attention due to their capabilities in forecasting, modelling of complex nonlinear systems and control. ANNs have been used for forecasting solar energy. This paper presented a study that examined a thermal photovoltaic solar integrated system that was built in Jordan. Historical input-output system data that was collected experimentally was used to train an ANN that predicted the collector, PV module, pump and total efficiencies. The model predicted the efficiencies well and can therefore be utilized to find the operating conditions of the system that will produce the maximum system efficiencies. The paper provided a description of the photovoltaic solar system including equations for PV module efficiency; pump efficiency; and total efficiency. The paper also presented data relevant to the system performance and neural networks. The results of a neural net model were also presented based on the thermal PV solar integrated system data that was collected. It was concluded that the neural net model of the thermal photovoltaic solar integrated system set the background for achieving the best system performance. 10 refs., 6 figs.

Solar Energy in the Nineteen Eighties

International Nuclear Information System (INIS)

Broda, E.

1979-01-01

Solar energy is abundant inexhaustible and nonpolluting. Its utilization does not affect the climate, and it does not lend itself to military applications. The solar-thermal, solar-electric and solar-chemical options are available. The production of low-temperature heat for warm water and for space heating, of enormous importance in the energy budget, is economic already now in many situations. Technical progress is still considerable. With the further rise in fuel prices the application will increase dramatically. Use of solar heat for large-scale generation of electricity, i.e. of power on the basis of the solar-thermal option, should be approached cautiously. Possibilities include the tower concept and ocean thermal-electric conversion (OTEC). Investment would be large, and the technology hard. Better long-term chances may be given, for decentralized application in developing countries, to the farm concept. In contrast, the chances for cheap small-scale, and later large-scale, use of solar semiconductor cells (solar-electric option) are most favourable. Technical progress is rapid, and prices drop precipitously. For the production of fuel, the solar-chemical option is in the foreground. Gaseous, liquid and convenient solid fuels can be obtained from biomass, especially by fermentation. At the moment, biogenic wastes are already available in relatively large amounts. Subsequently, energy farming is to be introduced. Biomass converted to hydrogen can be employed for production of electricity by means of fuel cells. In the more distant future, hydrogen is to be made abiotically by photolysis of water, and is to be introduced into a hydrogen economy. Probably the technology will be based on the application of synthetic membranes. It is possible that regenerative solar energy in all its forms can in the end replace all existing energy used by man. This substitution will s however, be a gradual process. (author)

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

Energy Technology Data Exchange (ETDEWEB)

None

1978-02-01

An evaluation of federal research, development, and demonstration options on solar energy is presented. This assessment treats seven groups of solar energy technologies: solar heating and cooling of buildings, agricultural and industrial process heat, biomass, photovoltaics, thermal power, wind, and ocean thermal energy conversion. The evaluation methodology is presented in detail. (MHR)

Interplanetary ions during an energetic storm particle event - The distribution function from solar wind thermal energies to 1.6 MeV

Science.gov (United States)

Gosling, J. T.; Asbridge, J. R.; Bame, S. J.; Feldman, W. C.; Zwickl, R. D.; Paschmann, G.; Sckopke, N.; Hynds, R. J.

1981-01-01

An ion velocity distribution function of the postshock phase of an energetic storm particle (ESP) event is obtained from data from the ISEE 2 and ISEE 3 experiments. The distribution function is roughly isotropic in the solar wind frame from solar wind thermal energies to 1.6 MeV. The ESP event studied (8/27/78) is superposed upon a more energetic particle event which was predominantly field-aligned and which was probably of solar origin. The observations suggest that the ESP population is accelerated directly out of the solar wind thermal population or its quiescent suprathermal tail by a stochastic process associated with shock wave disturbance. The acceleration mechanism is sufficiently efficient so that approximately 1% of the solar wind population is accelerated to suprathermal energies. These suprathermal particles have an energy density of approximately 290 eV cubic centimeters.

New materials for thermal energy storage in concentrated solar power plants

Science.gov (United States)

Guerreiro, Luis; Collares-Pereira, Manuel

2016-05-01

Solar Thermal Electricity (STE) is an important alternative to PV electricity production, not only because it is getting more cost competitive with the continuous growth in installed capacity, engineering and associated innovations, but also, because of its unique dispatch ability advantage as a result of the already well established 2-tank energy storage using molten salts (MS). In recent years, research has been performed, on direct MS systems, to which features like modularity and combinations with other (solid) thermal storage materials are considered with the goal of achieving lower investment cost. Several alternative materials and systems have been studied. In this research, storage materials were identified with thermo-physical data being presented for different rocks (e.g. quartzite), super concrete, and other appropriate solid materials. Among the new materials being proposed like rocks from old quarries, an interesting option is the incorporation of solid waste material from old mines belonging to the Iberian Pyritic Belt. These are currently handled as byproducts of past mine activity, and can potentially constitute an environmental hazard due to their chemical (metal) content. This paper presents these materials, as part of a broad study to improve the current concept of solar energy storage for STE plants, and additionally presents a potentially valuable solution for environmental protection related to re-use of mining waste.

Model of a thermal energy storage device integrated into a solar assisted heat pump system for space heating

International Nuclear Information System (INIS)

Badescu, Viorel

2003-01-01

Details about modelling a sensible heat thermal energy storage (TES) device integrated into a space heating system are given. The two main operating modes are described. Solar air heaters provide thermal energy for driving a vapor compression heat pump. The TES unit ensures a more efficient usage of the collected solar energy. The TES operation is modeled by using two non-linear coupled partial differential equations for the temperature of the storage medium and heat transfer fluid, respectively. Preliminary results show that smaller TES units provide a higher heat flux to the heat pump vaporiser. This makes the small TES unit discharge more rapidly during time periods with higher thermal loads. The larger TES units provide heat during longer time periods, even if the heat flux they supply is generally smaller. The maximum heat flux is extracted from the TES unit during the morning. Both the heat pump COP and exergy efficiency decrease when the TES unit length increases. Also, the monthly thermal energy stored by the TES unit and the monthly energy necessary to drive the heat pump compressor are increased by increasing the TES unit length

Solar energy promises realized?

International Nuclear Information System (INIS)

Oudshoff, B.

2010-01-01

The US market for solar cells grew 36% in 2009. Thousands of new jobs were created, many millions are invested and new businesses see new opportunities. Optimism among investors, incentivising government policy and new technological developments all contribute to these positive developments. This article provides an update of the incentive measures and their effects and a brief overview of the three solar energy technologies: photovoltaic (PV), solar thermal and concentrated solar power (CSP) [nl

Economic impact of solar thermal electricity deployment in Spain

International Nuclear Information System (INIS)

Caldes, N.; Varela, M.; Santamaria, M.; Saez, R.

2009-01-01

The objective of the work is to estimate the socio-economic impacts of increasing the installed solar thermal energy power capacity in Spain. Using an input-output (I-O) analysis, this paper estimates the increase in the demand for goods and services as well as in employment derived from solar thermal plants in Spain under two different scenarios: (a) based on two solar thermal power plants currently in operation (with 50 and 17 MW of installed capacity); (b) the compliance to the Spanish Renewable Energy Plan (PER) 2005-2010 reaching 500 MW by 2010. Results show that the multiplier effect of the PER is 2.3 and the total employment generated would reach 108,992 equivalent full-time jobs of 1 year of duration. Despite this is an aggregated result, this figure represents 4.5% of current Spanish unemployment. It can be concluded that the socio-economic effect of the PER's solar thermal installed capacity goal would be remarkable.

Acceleration of the solar-thermal energy development but still some brakes upon photovoltaic conversion

International Nuclear Information System (INIS)

Anon.

2006-01-01

France shows today the highest growth rate for solar thermal energy with respect to other European countries. This market is structuring and tries to favour quality. A label for systems certification has been presented in January 2007. Photovoltaic conversion has been tied up for a long time by poorly attractive power repurchase tariffs. It benefits now from a propitious framework for its development even if some financial incentive questions relative to the integration of solar panels to buildings remain unanswered. (J.S.)

Japan's Sunshine Project. Solar energy R and D program

Energy Technology Data Exchange (ETDEWEB)

NONE

1981-05-01

This paper explains the Sunshine Project and its solar energy R and D program. The solar energy is poured into the earth at 1.04 x 10{sup 17} kcal per hour, while the energy consumption of the world in 1970 is equivalent to 30 minutes of the solar energy. It is infinite compared to fossil fuel and clean, with no extreme partiality by areas. Its problem in utilization, however, is the low energy density of 1 kw/m{sup 2} and unsteady supply caused by weather conditions, which raises difficulties in matching energy demand. These demerits and low competitiveness in cost must be overcome through R and D. Under the Sunshine Project, the solar energy utilization is in progress in the areas of thermal utilization in a building, solar thermal power generation, and photovoltaic power generation. The budget was 9.6 billion yen for fiscal 1980 and 8 billion yen for fiscal 1981. Since fiscal 1980, emphasis has been placed particularly on photovoltaic power generation. The experimental production of solar cells of 500 kW/year is scheduled as a target through fiscal 1981-82. Four demonstration plants and two central distributing substations for photovoltaic power generation are planned to be built by fiscal 1985. Also to be studied are 2 solar thermal power generation plants of 1,000 kWe each and a solar thermal system for industrial process heating. (NEDO)

Selection of high temperature thermal energy storage materials for advanced solar dynamic space power systems

Science.gov (United States)

Lacy, Dovie E.; Coles-Hamilton, Carolyn; Juhasz, Albert

1987-01-01

Under the direction of NASA's Office of Aeronautics and Technology (OAST), the NASA Lewis Research Center has initiated an in-house thermal energy storage program to identify combinations of phase change thermal energy storage media for use with a Brayton and Stirling Advanced Solar Dynamic (ASD) space power system operating between 1070 and 1400 K. A study has been initiated to determine suitable combinations of thermal energy storage (TES) phase change materials (PCM) that result in the smallest and lightest weight ASD power system possible. To date the heats of fusion of several fluoride salt mixtures with melting points greater than 1025 K have been verified experimentally. The study has indicated that these salt systems produce large ASD systems because of their inherent low thermal conductivity and low density. It is desirable to have PCMs with high densities and high thermal conductivities. Therefore, alternate phase change materials based on metallic alloy systems are also being considered as possible TES candidates for future ASD space power systems.

Solar Thermal Energy Exploitation: An Opportunity to Enhance Conceptual Learning in Physics

Science.gov (United States)

Rodrigues, M. A.; Cravino, J. P.; Liberato, M. L. R.

2010-05-01

In a society mainly driven by Science and Technology it is becoming consensual the idea that scientific education should include three components: Education in Science, Education about Science and Education through Science. Some authors suggest that, in education, everyday objects should be used to illustrate scientific issues (e.g. Andrée, 2005). Thus the goal of this study is two-fold: first, to develop a teaching and learning strategy, in the framework of Education for Sustainable Development (ESD), concerning the renewable energy issue, while showing the importance of using everyday situations in the improvement of students' motivation in Physics learning. Energy is the core concept in this study. Energy conservation includes the concepts applied to sustainable balance between environment and the energy availability and use. Dias et al. (2004) stress that education is one of the best ways to transform the human behavior for the rational use of energy, which represents a long-term investment. In this work students become aware and recognize the importance and value of energy in everyday life, they identify energy transfer and transformation processes, confirm energy availability, relating these topics to present human needs and climate change issues. A didactic model of a solar thermal panel has thus been built, using cheap, common materials, by 15-16 year-old Physics students, from a Portuguese secondary school. Students had to plan the experiments, in small groups, to identify and estimate physical magnitudes and to explore how to maximize the solar thermal panel efficiency. The experimental activities took place in the school's playground, in a place where there were no obstacles to capturing solar radiation. Finally, students had to deal with experimental data acquisition and analysis, they had to prepare a report, as well as to answer a survey, to evaluate their learning success. Results show that students appreciated the proposed themes and activities

Market potential and market hindrances for thermal solar energy; Marktpotentiale und Markthindernisse fuer die thermische Solarenergie

Energy Technology Data Exchange (ETDEWEB)

Gerheuser, F. W.

2002-10-15

This comprehensive report for the Swiss Federal Office of Energy (SFOE) discusses the market potential and market hindrances for thermal solar energy systems. The author notes that solar systems for heating domestic hot water have a considerable market potential, especially for single-family homes. Such installations are discussed in detail, whereby not only technicalities but also market image and the latent potential for such systems are discussed. The results of surveys made are presented and discussed. The lower potential for installations on apartment blocks is also mentioned.

Solar cooling for small office buildings: Comparison of solar thermal and photovoltaic options for two different European climates

Energy Technology Data Exchange (ETDEWEB)

Hartmann, N. [University of Stuttgart, Institute of Energy Economics and the Rational Use of Energy (IER), Hessbruehlstr. 49a, 70565 Stuttgart (Germany); Glueck, C. [Karlsruhe Institute of Technology (KIT), Institute of Fluid Machinery (FSM), Kaiserstr. 12, 76131 Karlsruhe (Germany); Schmidt, F.P. [Karlsruhe Institute of Technology (KIT), Institute of Fluid Machinery (FSM), Kaiserstr. 12, 76131 Karlsruhe (Germany); Fraunhofer ISE, Heidenhofstr. 2, 79110 Freiburg (Germany)

2011-05-15

We present a comparison of solar thermal and solar electric cooling for a typical small office building exposed to two different European climates (Freiburg and Madrid). The investigation is based on load series for heating and cooling obtained previously from annual building simulations in TRNSYS. A conventional compression chiller is used as the reference system against which the solar options are evaluated with respect to primary energy savings and additional cost. A parametric study on collector and storage size is carried out for the solar thermal system to reach achieve the minimal cost per unit of primary energy saved. The simulated solar electric system consists of the reference system, equipped with a grid connected photovoltaic module, which can be varied in size. For cost comparison of the two systems, the electric grid is assumed to function as a cost-free storage. A method to include macroeconomic effects in the comparison is presented and discussed. Within the system parameters and assumptions used here, the grid coupled PV system leads to lower costs of primary energy savings than the solar thermal system at both locations. The presumed macroeconomic advantages of the solar thermal system, due to the non-usage of energy during peak demand, can be confirmed for Madrid. (author)

Conversion of solar energy into heat

International Nuclear Information System (INIS)

Devin, B.; Etievant, C.

1975-01-01

Argument prevails regarding the main parameters involved in the definition of installations designed to convert by means of a thermal machine, solar energy into electrical or mechanical energy. Between the temperature of the cold source and the stagnation temperature, there exists an optimal temperature which makes for the maximum efficiency of the collector/thermal machine unit. The optimal operating conditions for different types of collector are examined. Optimization of the surface of the collector is dealt with in particular. The structure and cost of solar installations are also analyzed with some examples as basis: solar pumps of 1 to 25kW, a 50MWe electrosolar plant. The cost involves three main elements: the collector, the thermal unit and the heat storage device. The latter is necessary for the integration of diurnal and nocturnal fluctuations of isolation. It is shown that thermal storage is economically payable only under certain conditions [fr

Low cost thermal solar collector

International Nuclear Information System (INIS)

Abugderah, M. M.; Schneider, E. L.; Tontini, M. V.

2006-01-01

Solar energy is a good alternative in the economy of the electric energy mainly for the water heating. However, the solar heaters used demand a high initial investment, becoming the warm water from solar energy inaccessible to a large part of the society. Thus, a low cost solar heater was developed, constructed and tested in the chemical engineering department of West Parana State University-Unioeste. This equipment consists of 300 cans, divided in 30 columns of 10 cans each, all painted in black to enhance the obsorption of the solar radiation. The columns are connected to a pipe of pvc of 8 liters with 0.085m of external diameter. The equipment is capable to heat 120 liters of water in temperatures around 60 degree centigrade. The heater is insolated in its inferior part with cardboard and aluminum, covered with a transparent plastic in its superior. The system still counts with a insulated thermal reservoir, which can conserve the water in temperatures adjusted for the night non-solar days domestic use. The advantage of the constructed is it low cost material. The results are given an graphical tabular from showing acceptable efficiencies.(Autho

Solar energy in practice

International Nuclear Information System (INIS)

Eijpe, H.A.

1996-01-01

One of the Dutch energy distribution companies (REMU) applies integrated passive, thermal and photovoltaic solar energy systems in fifty newly built dwellings in Amersfoort, Netherlands. The houses are equipped with a combi-boiler (solar energy and natural gas) and 22.5m 2 photovoltaic panels to produce electricity. Six houses are equipped with an electric heat pump, while the other 44 houses have a high-efficiency low-NO x combi-boiler. The experiences with the project so-far are outlined. 6 figs., 1 tab., 10 refs

Solar Thermal energy strategic road-map

International Nuclear Information System (INIS)

Hafner, Bernd; Godin, Olivier; Villier, Dominique; Petit, J.F.; Demangeon, Elsa; Laplagne, Valerie; Loyen, Richard; Mugnier, Daniel; Filloux, Alain; Frichet, Jean-Claude; Aubert, Elisabeth; Cherepanova, Margarita; Guilmin, Audrey; Dicostanzo, Catherine; Papillon, Philippe; Caccavelli, Dominique; Cholin, Xavier; Leger, Emmanuel; Gevaudan, Alain; Coulaud, Celine; Morlot, Rodolphe; Khebchache, Bouzid; Parrouffe, Jean-Michel; Clement, Daniel; Tonnet, Nicolas

2012-11-01

The French Environment and Energy Management Agency (ADEME) manages a fund dedicated to new energy technologies. Since 2008 this fund has funded 'research demonstrators' to implement testing of technologies that are in an experimental stage, between research and industrial deployment. ADEME coordinates a group of experts who are charged with drawing up a strategic road-map prior to each Call for Expressions of Interest. The aims of the solar thermal road-map are: - to highlight the industrial, technological, environmental and societal issues at stake; - to elaborate coherent, consistent and shared visions of the technologies and/or socio-technical systems outlined in the road-map; - to underscore the technological, organisational and socioeconomic barriers and bottlenecks to be overcome in order to achieve these visions; - to link priority research topics to a timetable of goals for technology availability and deployment that is consistent with the stated objectives; - to give priority to research needs and research demonstrators that will serve as the basis for: 1 - calls for expression of interest issued by the Research Demonstrators Fund, 2 - the research programming process at ADEME and more broadly at the Agence nationale de la recherche (ANR) and the Comite strategique national sur la recherche sur l'energie. Research priorities and needs for demonstrators are determined by the intersection of visions and bottlenecks. They also take into account industrial and research capacity in France. The road-maps may also refer to exemplary research demonstrators abroad that are in the forefront of technological progress, and make recommendations regarding industrial policy. These road-maps are the result of collective work by a group of experts appointed by the Steering Committee (Comite de pilotage, COPIL) of the Research Demonstrators Fund for new energy technologies. The members of this group are actors in research, drawn from industry, research bodies and research

Characteristics of evacuated tubular solar thermal collector as input energy for cooling system at Universitas Indonesia

Science.gov (United States)

Alhamid, M. Idrus; Nasruddin, Aisyah, Nyayu; Sholahudin

2017-03-01

This paper discussed the use of solar thermal collector as an input energy for cooling system. The experimental investigation was undertaken to characterize solar collectors that have been integrated with an absorption chiller. About 62 modules of solar collectors connected in series and parallel are placed on the roof top of MRC building. Thermistors were used to measure the fluid temperature at inlet, inside and outlet of each collector, inside the water tank and ambient temperature. Water flow that circulated from the storage was measured by flow meter, while solar radiation was measured by a pyranometer that was mounted parallel to the collector. Experimental data for a data set was collected in March 2016, during the day time hours of 08:00 - 17:00. This data set was used to calculate solar collector efficiency. The results showed that in the maximum solar radiation, the outlet temperature that can be reached is about 78°C, the utilized energy is about 70 kW and solar collector has an efficiency of 64%. While in the minimum solar radiation, the outlet temperature that can be reached is about 53°C, the utilized energy is about 28 kW and solar collector has an efficiency of 43%.

Design aspects of integrated compact thermal storage system for solar dryer applications

International Nuclear Information System (INIS)

Rajaraman, R.; Velraj, R.; Renganarayanan, S.

2000-01-01

Solar energy is an excellent source for drying of crops, fruits, vegetables and other agricultural and forest products. Though the availability of solar energy is plenty, it is time dependent in nature. The energy need for some applications is also time dependent, but in a different pattern and phase from the solar energy supply. This implies that the solar dryer should be integrated with an efficient thermal storage system to match the time-dependent supply and end-use requirements. Based on the studies carried out on Latent Heat Thermal Storage (LHTS) Systems, it is observed that when air is used as the heat transfer fluid in LHTS system, nearly uniform surface heat flux can be achieved. Hence the LHTS systems are most suitable for air based solar drying applications. In the present work some major conclusions arrived from the investigations on LHTS systems and the design considerations for the integrated latent heat thermal storage for the solar dryer are reported. (Author)

When the solar energy pays

International Nuclear Information System (INIS)

Laramee, V.

1997-01-01

In the californian desert of Mojave, the three biggest solar power plants in the world produce 90% of world solar electric power. They have been operating for ten years, and their managers go on to improve them. These installations beat the productivity record every year, proving that the thermal solar energy can be competitive. (N.C.)

Solar energy in the United States

International Nuclear Information System (INIS)

Ochoa, D.; Slaoui, A.; Soler, R.; Bermudez, V.

2009-01-01

Written by a group of five French experts who visited several research centres, innovating companies and solar power stations in the United States, this report first proposes an overview of solar energy in the United States, indicating and commenting the respective shares of different renewable energies in the production, focusing on the photovoltaic energy production and its RD sector. The second part presents industrial and research activities in the solar sector, and more specifically photovoltaic technologies (silicon and thin layer technology) and solar concentrators (thermal solar concentrators, photovoltaic concentrators). The last chapter presents the academic research activities in different universities (California Tech Beckman Institute, Stanford, National Renewable Energy Laboratory, Colorado School of Mines)

The thermal solar at the dawn of a necessary revolution

International Nuclear Information System (INIS)

Zebboudj, Idir

2013-01-01

This article proposes an overview of the difficult situation which the thermal solar sector is now facing in France (after a constant increase until 2008, its market keeps on shrinking and is not attractive enough). It discusses the implications and possible benefits the new thermal regulation (RT 2012) for new buildings could have for this energy, and whether it will be at the heart of the planned and expected energy transition. A new concept of water heater is presented which associates thermal solar and gas

Thermo-economic analysis of Shiraz solar thermal power plant

Energy Technology Data Exchange (ETDEWEB)

Yaghoubi, M. [Academy of Science, Tehran (Iran, Islamic Republic of); Mokhtari, A.; Hesami, R. [Shiraz Univ., Shiraz (Iran, Islamic Republic of). School of Engineering

2007-07-01

The Shiraz solar thermal power plant in Iran has 48 parabolic trough collectors (PTCs) which are used to heat the working oil. There is potential to significantly increase the performance and reduce the cost of PTC solar thermal electric technologies. Conventional energy analysis based on the first law of thermodynamics does qualitatively assess the various losses occurring in the components. Therefore, exergy analysis, based on the second law of thermodynamics, can be applied to better assess various losses quantitatively as well as qualitatively. This paper presented a newly developed exergy-economic model for the Shiraz solar thermal power plant. The objective was to find the minimum exergetic production cost (EPC), based on the second law of thermodynamics. The application of exergy-economic analysis includes the evaluation of utility supply costs for production plants, and the energy costs for process operations. The purpose of the analysis was to minimize the total operating costs of the solar thermal power plant by assuming a fixed rate of electricity production and process steam. 21 refs., 3 tabs., 8 figs.

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.

Lessons learned from solar energy projects in Saudi Arabia

International Nuclear Information System (INIS)

Huraib, F.S.; Hasnain, S.M.; Alawaji, S.H.

1996-01-01

This paper describes the lessons learned from the major RD and D activities at Energy Research Institute (ERI), King Abdulaziz City for Science and Technology (KACST) in the field of solar energy. Photovoltaic, solar thermal dishes, solar water heating, solar water pumping and desalination, solar hydrogen production and utilization are some of the areas studied for solar energy applications. Recommendations and guidelines for future solar energy research, development, demonstration and dissemination in Saudi Arabia are also given. (Author)

Renewable energy distributed power system with photovoltaic/ thermal and bio gas power generators

International Nuclear Information System (INIS)

Haider, M.U.; Rehman, S.U.

2011-01-01

The energy shortage and environmental pollution is becoming an important problem in these days. Hence it is very much important to use renewable power technologies to get rid of these problems. The important renewable energy sources are Bio-Energy, Wind Energy, Hydrogen Energy, Tide Energy, Terrestrial Heat Energy, Solar Energy, Thermal Energy and so on. Pakistan is rich in all these aspects particularly in Solar and Thermal Energies. In major areas of Pakistan like in South Punjab, Sind and Baluchistan the weather condition are very friendly for these types of Renewable Energies. In these areas Solar Energy can be utilized by solar panels in conjunction with thermal panels. The Photovoltaic cells are used to convert Solar Energy directly to Electrical Energy and thermal panels can be uses to convert solar energy into heat energy and this heat energy will be used to drive some turbine to get Electrical Energy. The Solar Energy can be absorbed more efficiently by any given area of Solar Panel if these two technologies can be combined in such a way that they can work together. The first part of this paper shows that how these technologies can be combined. Furthermore it is known to all that photovoltaic/thermal panels depend entirely on weather conditions. So in order to maintain constant power a biogas generator is used in conjunction with these. (author)

A novel polygeneration system integrating photovoltaic/thermal collectors, solar assisted heat pump, adsorption chiller and electrical energy storage: Dynamic and energy-economic analysis

International Nuclear Information System (INIS)

Calise, Francesco; Figaj, Rafal Damian; Vanoli, Laura

2017-01-01

Highlights: • Space heating/cooling, domestic hot water and electrical energy are provided by the system. • Two different users are investigated: fitness center and office. • The influence of the battery system on system economic performance is scarce. • Net metering contract is more profitable compared to simplified purchase/resale arrangement one. - Abstract: In this paper a dynamic simulation model and a thermo-economic analysis of a novel polygeneration system are presented. The system includes photovoltaic/thermal collectors coupled with a solar-assisted heat pump, an adsorption chiller and an electrical energy storage. The modelled plant supplies electrical energy, space heating and cooling and domestic hot water. The produced solar thermal energy is used during the winter to supply the heat pump evaporator, providing the required space heating. In summer, solar thermal energy is used to drive an adsorption chiller providing the required space cooling. All year long, solar thermal energy in excess, with respect to the space heating and cooling demand, is used to produce domestic hot water. The produced electrical energy is self-consumed by both user and system auxiliary equipment and/or supplied to the grid. The system model includes a detailed electrical energy model for user storage and exchange with the grid along with a detailed building model. This study is a continuation of previous works recently presented by the authors. In particular, the present paper focuses on the real electrical demands of several types of users and on the analysis of the comfort of building users. Differently from the works previously published by the authors, the present work bases the calculations on measured electrical demands of real users (fitness center and offices). The system performance is analyzed with two different electricity supply contracts: net metering and simplified purchase/resale arrangement. Daily, weekly and yearly results are presented. Finally, a

THERMAL PERFORMANCE OF FLAT PLATE SOLAR COLLECTOR

Directory of Open Access Journals (Sweden)

TABET I.

2017-06-01

Full Text Available In this paper, a theoretical and experimental studyof flat platesolar water collector with reflectors.A mathematical model based on energy balance equations saw the thermal behavior of the collector is investigated. The experimental test was made at the unit research applies in renewable energy (URAER located in southern Algeria.An increase of 23% for solar radiation incident on the collector surface with the addition of the planers reflectors in the day of May, this increase causes an improvement of the performance of the collector,the fluid temperature increases with an average of 5%. Thetests conducted on the flat plate solar water collector in open circuit enabled the determination of thermal performance of the collector by estimating the daily output The thermal efficiency of the collector ranges from 1% -63% during the day, a mean value of 36%obtained.

Simulation study on reduction of peak power demand and energy consumption in residential houses with solar thermal and PV systems; Taiyo energy riyo jutaku no fuka heijunka oyobi energy sakugen koka no simulation ni yoru kento

Energy Technology Data Exchange (ETDEWEB)

Endo, T. [Yokohama City Office, Yokohama (Japan); Udagawa, M. [Kogakuin Univ., Tokyo (Japan). Faculty of Engineering

1995-11-20

In this study, taking the all factors involved in the energy consumption in residential houses as subjects, the effectiveness of the solar PV system and solar thermal utilizing system in residential houses has been studied by simulating a model residential house considering the improvement of the residual environment in the future. Therefore, a model residual house is assumed, 18 kinds of combinations of construction style, cooling and heating type and solar energy utilizing form are assumed and year round simulation is carried out. The conclusions obtained by the simulation are as follows. The energy consumption in residential houses may decrease greatly by using a solar hot water supplying system. If combined with a solar PV system, the energy consumption in one year is about 8.7 to 9.7 MWh. The combined use of a solar thermal utilizing system and a PV system is more effective to reduce the second-time energy in comparison with the PV system only. 36% of the space heating energy consumption may be decreased by using the solar space heating system, but the decrease effect of the energy consumption of the solar space heating system is smaller than the solar hot water supplying system. 12 refs., 26 figs., 3 tabs.

Solar thermal technology development: Estimated market size and energy cost savings. Volume 2: Assumptions, methodology and results

Science.gov (United States)

Gates, W. R.

1983-02-01

Estimated future energy cost savings associated with the development of cost-competitive solar thermal technologies (STT) are discussed. Analysis is restricted to STT in electric applications for 16 high-insolation/high-energy-price states. Three fuel price scenarios and three 1990 STT system costs are considered, reflecting uncertainty over future fuel prices and STT cost projections. Solar thermal technology research and development (R&D) is found to be unacceptably risky for private industry in the absence of federal support. Energy cost savings were projected to range from $0 to $10 billion (1990 values in 1981 dollars), depending on the system cost and fuel price scenario. Normal R&D investment risks are accentuated because the Organization of Petroleum Exporting Countries (OPEC) cartel can artificially manipulate oil prices and undercut growth of alternative energy sources. Federal participation in STT R&D to help capture the potential benefits of developing cost-competitive STT was found to be in the national interest. Analysis is also provided regarding two federal incentives currently in use: The Federal Business Energy Tax Credit and direct R&D funding.

Solar thermal technology development: Estimated market size and energy cost savings. Volume 2: Assumptions, methodology and results

Science.gov (United States)

Gates, W. R.

1983-01-01

Estimated future energy cost savings associated with the development of cost-competitive solar thermal technologies (STT) are discussed. Analysis is restricted to STT in electric applications for 16 high-insolation/high-energy-price states. Three fuel price scenarios and three 1990 STT system costs are considered, reflecting uncertainty over future fuel prices and STT cost projections. Solar thermal technology research and development (R&D) is found to be unacceptably risky for private industry in the absence of federal support. Energy cost savings were projected to range from $0 to $10 billion (1990 values in 1981 dollars), depending on the system cost and fuel price scenario. Normal R&D investment risks are accentuated because the Organization of Petroleum Exporting Countries (OPEC) cartel can artificially manipulate oil prices and undercut growth of alternative energy sources. Federal participation in STT R&D to help capture the potential benefits of developing cost-competitive STT was found to be in the national interest. Analysis is also provided regarding two federal incentives currently in use: The Federal Business Energy Tax Credit and direct R&D funding.

The potential of solar energy in the Netherlands

International Nuclear Information System (INIS)

Sinke, W.C.; De Geus, A.C.

1993-01-01

Solar energy in the Netherlands is not yet a well-known phenomenon. Still, the potential of solar energy to save or generate energy is large. Several forms of solar energy, as well as its possibilities and limitations, are introduced in this article. Attention is paid to active and passive thermal solar energy, and photovoltaic solar energy. Also the involvement of different parties in introducing solar energy is discussed. The next 10-20 years will be characterized by large-scale practical experiments and market introduction. The application of solar energy should be taken into account when planning urban areas. It is expected that ongoing developments in all fields of solar energy will result in a considerable improvement of the price/performance ratio and many new possibilities. 4 figs., 4 ills., 14 refs

Output performance analyses of solar array on stratospheric airship with thermal effect

International Nuclear Information System (INIS)

Li, Jun; Lv, Mingyun; Tan, Dongjie; Zhu, Weiyu; Sun, Kangwen; Zhang, Yuanyuan

2016-01-01

Highlights: • A model investigating the output power of solar array is proposed. • The output power in the cruise condition with thermal effect is researched. • The effect of some factors on output performance is discussed in detail. • A suitable transmissivity of external layer is crucial in preliminary design step. - Abstract: Output performance analyses of the solar array are very critical for solving the energy problem of a long endurance stratospheric airship, and the solar cell efficiency is very sensitive to temperature of the solar cell. But the research about output performance of solar array with thermal effect is rare. This paper outlines a numerical model including the thermal model of airship and solar cells, the incident solar radiation model on the solar array, and the power output model. Based on this numerical model, a MATLAB computer program is developed. In the course of the investigation, the comparisons of the simulation results with and without considering thermal effect are reported. Furthermore, effects of the transmissivity of external encapsulation layer of solar array and wind speed on the thermal performance and output power of solar array are discussed in detail. The results indicate that this method is helpful for planning energy management.

Solar-Thermal Engine Testing

Science.gov (United States)

Tucker, Stephen; Salvail, Pat; Haynes, Davy (Technical Monitor)

2001-01-01

A solar-thermal engine serves as a high-temperature solar-radiation absorber, heat exchanger, and rocket nozzle. collecting concentrated solar radiation into an absorber cavity and transferring this energy to a propellant as heat. Propellant gas can be heated to temperatures approaching 4,500 F and expanded in a rocket nozzle, creating low thrust with a high specific impulse (I(sub sp)). The Shooting Star Experiment (SSE) solar-thermal engine is made of 100 percent chemical vapor deposited (CVD) rhenium. The engine 'module' consists of an engine assembly, propellant feedline, engine support structure, thermal insulation, and instrumentation. Engine thermal performance tests consist of a series of high-temperature thermal cycles intended to characterize the propulsive performance of the engines and the thermal effectiveness of the engine support structure and insulation system. A silicone-carbide electrical resistance heater, placed inside the inner shell, substitutes for solar radiation and heats the engine. Although the preferred propellant is hydrogen, the propellant used in these tests is gaseous nitrogen. Because rhenium oxidizes at elevated temperatures, the tests are performed in a vacuum chamber. Test data will include transient and steady state temperatures on selected engine surfaces, propellant pressures and flow rates, and engine thrust levels. The engine propellant-feed system is designed to Supply GN2 to the engine at a constant inlet pressure of 60 psia, producing a near-constant thrust of 1.0 lb. Gaseous hydrogen will be used in subsequent tests. The propellant flow rate decreases with increasing propellant temperature, while maintaining constant thrust, increasing engine I(sub sp). In conjunction with analytical models of the heat exchanger, the temperature data will provide insight into the effectiveness of the insulation system, the structural support system, and the overall engine performance. These tests also provide experience on operational

Experimental investigation on photothermal properties of nanofluids for direct absorption solar thermal energy systems

International Nuclear Information System (INIS)

He, Qinbo; Wang, Shuangfeng; Zeng, Shequan; Zheng, Zhaozhi

2013-01-01

Highlights: • The factors affecting the transmittance of Cu–H 2 O nanofluids were studied with UV–Vis–NIR spectrophotometer. • The optical properties of Cu–H 2 O nanofluids were studied through the theoretical model. • The Cu–H 2 O nanofluids can enhance the absorption ability for solar energy. - Abstract: In this article, Cu–H 2 O nanofluids were prepared through two-step method. The transmittance of nanofluids over solar spectrum (250–2500 nm) was measured by the UV–Vis–NIR spectrophotometer based on integrating sphere principle. The factors influencing transmittance of nanofluids, such as particle size, mass fraction and optical path were investigated. The extinction coefficients measured experimentally were compared with the theoretical calculation value. Meanwhile, the photothermal properties of nanofluids were also investigated. The experimental results show that the transmittance of Cu–H 2 O nanofluids is much less than that of deionized water, and decreases with increasing nanoparticle size, mass fraction and optical depth. The highest temperature of Cu–H 2 O nanofluids (0.1 wt.%) can increased up to 25.3% compared with deionized water. The good absorption ability of Cu–H 2 O nanofluids for solar energy indicates that it is suitable for direct absorption solar thermal energy systems

Barriers to the Diffusion of Solar Thermal Technologies

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

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

Drying of Rhinacanthus nasutus (Linn. Kurz. using a solar dryer incorporated with a backup thermal energy storage from wood combustion

Directory of Open Access Journals (Sweden)

Perapong Tekasakul

2006-05-01

Full Text Available An indirect, natural convection, solar cabinet dryer incorporated with a backup thermal energy storage from wood combustion was designed and tested with the Thai herb, Rhinacanthus nasutus (Linn. Kurz. Most of Thai herbs are widely used as traditional medicine and drying is an initial step in the production process. Solar dryer with a biomass backup heating system is the most feasible solution to drying in Thailand. In this work, a 4 m x 5 m solar collector was used to absorb solar radiation for heating the incoming air during the daytime, while a biomass burner was used to supply heat when solar energy was not possible. Heat from fuelwood combustion was accumulated in the thermal storage system made of bricks, and was used to heat up the incoming air. Results showed that the herb was dried uniformly and the temperature inside the drying cabinet could be maintained above 50ºC for more than 10 hours. Thermal efficiency when using solar energy was 10.5%, but the value was less than 1% when using the heat from biomass burning. This resulted from the low moisture content of the products after being dried by the solar energy. The dryer is beneficial to the operators, particularly in southern Thailand, where continuous drying is required. This dryer is by no means limited to drying of the herb. Currently, four dryers of the same model have been used by farmer groups in southern Thailand for drying bananas, several types of herbs, fish, and other products. In economic consideration, its payback period is 5.5 years when compared with the LPG-equipped dryer. When the total cost and production capacity are considered, its payback period is about 6 years.

Photovoltaic Thermal panels in collective thermal solar systems

International Nuclear Information System (INIS)

Elswijk, M.J.; Strootman, K.J.; Jong, M.J.M.; De Lange, E.T.N.; Smit, W.F.

2003-12-01

A feasibility study has been carried out to assess the options to apply photovoltaic/thermal panels (PVT-panels) in collective solar thermal systems in urban areas in the Netherlands. The study was focused on the technical (architecture and installations) and the economical feasibility of collective PVT-systems in comparison with conventional solar thermal systems and combinations of photovoltaic (PV) panels and solar collectors. The results of the study also give insight into cost and the market for PVT-panels. Three case studies in which collective solar collector systems were applied are analyzed again by simulating the installation of a PVT-panels system and a separate solar thermal PV system [nl

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

Energy Technology Data Exchange (ETDEWEB)

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

2006-07-01

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

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)

FNCCR/Enerplan day 'Thermal solar for all territories'. Collection of contributions

International Nuclear Information System (INIS)

Perrin, Guillaume; Loyen, Richard; Porcheyre, Edwige; Greau, David; Boisleux, Francois; Roger, Christophe; Mariani, Christian; Mugnier, Daniel; Frey, Johan; Paulus, Cedric; Egret, Dominique; Muller, Marius

2018-04-01

Contributions to this day on the use of thermal solar installations (on building or for injection into a heat network) are proposed under the form of Power Point presentations. More precisely, after a general introduction with an overview of recent events in the energy sector, the authors address the renewal of the thermal solar sector (financial aspects, the SOCOL approach, performance markets), the development of solar energy in territories (study in Hauts-de-France, of support arrangements, large projects), the implementation of a regional support, an installation in an establishment for elderly and dependent people, a return on experience from a heat network with storage, the role of thermal solar in heat networks, the implementation of a new project (a heat network in Chateaubriant), and the innovative use of solar energy to produce cold

Solar energy. A way out of the eco-energy dilemma. Sonnenenergie. Ausweg aus dem Oeko-Dilemma

Energy Technology Data Exchange (ETDEWEB)

Karamanolis, S

1991-01-01

The book gives a comprehensive view of the state of the art of solar research and the uses of solar energy. Thermal applications, photovoltaic energy conversion, energy storage, hydrogen production and solar architecture are discussed in detail. A global solar energy conception is presented as a future outlook. (KW).

Solar energy - status and perspectives

Energy Technology Data Exchange (ETDEWEB)

Ahm, P. [PA Energy A/S, Malling (Denmark)

2007-05-15

Solar energy in terms of thermal Solar Hot Water systems and electricity producing Photovoltaics contribute at present only to the global energy supply at a fraction of 1 %. However, the potential for solar energy is immense: the earth receives in 1 hour from the sun the equivalent of the present annual global energy supply. Solar energy is one of the emerging renewable energy technologies still not competitive, but exhibiting both technical and economic potential to be so inside 10-15 years. There is basically no necessary 'technology jumps' as prerequisites, but such a development will demand a favorable political climate. Growing political awareness, driven partly by environmental concerns partly by concerns about security of energy supply, of the need to promote solar energy and renewables, e.g. on global level spurred on by the recent UN/IPCC report and on an EU level by the EC commitment to reach 20 % renewables in the electricity supply by 2010 and 20 % renewables in the overall energy production by 2020, appears to ensure the necessary future political support for renewables, but not necessarily for solar energy technologies, in particular photovoltaics's, which is still not yet competitive to other renewables although exhibiting a tremendous potential. (au)

Practical considerations for solar energy thermally enhanced photo-luminescence (TEPL) (Conference Presentation)

Science.gov (United States)

Kruger, Nimrod; Manor, Assaf; Kurtulik, Matej; Sabapathy, Tamilarasan; Rotschild, Carmel

2017-04-01

While single-junction photovoltaics (PV's) are considered limited in conversion efficiency according to the Shockley-Queisser limit, concepts such as solar thermo-photovoltaics aim to harness lost heat and overcome this barrier. We claim the novel concept of Thermally Enhanced Photoluminescence (TEPL) as an easier route to achieve this goal. Here we present a practical TEPL device where a thermally insulated photo-luminescent (PL) absorber, acts as a mediator between a photovoltaic cell and the sun. This high temperature absorber emits blue-shifted PL at constant flux, then coupled to a high band gap PV cell. This scheme promotes PV conversion efficiencies, under ideal conditions, higher than 62% at temperatures lower than 1300K. Moreover, for a PV and absorber band-gaps of 1.45eV (GaAs PV's) and 1.1eV respectively, under practical conditions, solar concentration of 1000 suns, and moderate thermal insulation; the conversion efficiencies potentially exceed 46%. Some of these practical conditions belong to the realm of optical design; including high photon recycling (PR) and absorber external quantum efficiency (EQE). High EQE values, a product of the internal QE of the active PL materials and the extraction efficiency of each photon (determined by the absorber geometry and interfaces), have successfully been reached by experts in laser cooling technology. PR is the part of emitted low energy photons (in relation to the PV band-gap) that are reabsorbed and consequently reemitted with above band-gap energies. PV back-reflector reflectivity, also successfully achieved by those who design the cutting edge high efficiency PV cells, plays a major role here.

Optimization of a PV/T (photovoltaic/thermal) active solar still

International Nuclear Information System (INIS)

Saeedi, F.; Sarhaddi, F.; Behzadmehr, A.

2015-01-01

In this paper, the optimization of a PV/T (photovoltaic/thermal) active solar still is carried out. Analytical expressions for glass cover temperature, basin temperature, brackish water temperature and fresh water productivity are obtained by writing energy balance for different components of PV/T active solar still. The output electrical power of PV/T active solar still is calculated by four-parameter I–V (current–voltage) model. Objective function in present study is the energy efficiency of PV/T active solar still. A computer simulation program has been developed in order to obtain thermal and electrical parameters, respectively. The simulation results of the present study are in fair agreement with the experimental data of previous literatures. Finally, the optimization of PV/T active solar still has been carried out and the optimized value of mass flow rate, number of PV/T collector and the objective function have been obtained. Furthermore, the effect of various operating parameters on energy efficiency have been investigated. - Highlights: • The comprehensive optimization of a PV/T active solar still is carried out. • Present study is based on numerical simulation. • A modified energy efficiency for PV/T active solar still is obtained. • The effect of design and operating parameters is investigated on energy efficiency

Heat pipe solar receiver with thermal energy storage

Science.gov (United States)

Zimmerman, W. F.

1981-01-01

An HPSR Stirling engine generator system featuring latent heat thermal energy storge, excellent thermal stability and self regulating, effective thermal transport at low system delta T is described. The system was supported by component technology testing of heat pipes and of thermal storage and energy transport models which define the expected performance of the system. Preliminary and detailed design efforts were completed and manufacturing of HPSR components has begun.

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

Science.gov (United States)

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

2017-05-31

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

Can industry afford solar energy

Science.gov (United States)

Kreith, F.; Bezdek, R.

1983-03-01

Falling oil prices and conservation measures have reduced the economic impetus to develop new energy sources, thus decreasing the urgency for bringing solar conversion technologies to commercial readiness at an early date. However, the capability for solar to deliver thermal energy for industrial uses is proven. A year-round operation would be three times as effective as home heating, which is necessary only part of the year. Flat plate, parabolic trough, and solar tower power plant demonstration projects, though uneconomically operated, have revealed engineering factors necessary for successful use of solar-derived heat for industrial applications. Areas of concern have been categorized as technology comparisons, load temperatures, plant size, location, end-use, backup requirements, and storage costs. Tax incentives have, however, supported home heating and not industrial uses, and government subsidies have historically gone to conventional energy sources. Tax credit programs which could lead to a 20% market penetration by solar energy in the industrial sector by the year 2000 are presented.

Solar energy legal bibliography. Final report. [160 references

Energy Technology Data Exchange (ETDEWEB)

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

1979-03-01

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

Methods for Analyzing the Economic Value of Concentrating Solar Power with Thermal Energy Storage

Energy Technology Data Exchange (ETDEWEB)

Denholm, Paul [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jorgenson, Jennie [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Miller, Mackay [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Zhou, Ella [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Wang, Caixia [State Grid Energy Research Inst., Beijing (China)

2015-07-20

Concentrating solar power with thermal energy storage (CSP-TES) provides multiple quantifiable benefits compared to CSP without storage or to solar photovoltaic (PV) technology, including higher energy value, ancillary services value, and capacity value. This report describes modeling approaches to quantifying these benefits that have emerged through state-level policymaking in the United States as well as the potential applicability of these methods in China. The technical potential for CSP-TES in China is significant, but deployment has not yet achieved the targets established by the Chinese government. According to the 12th Five Year Plan for Renewable Energy (2011-2015), CSP was expected to reach 1 GW by 2015 and 3 GW by 2020 in China, yet as of December 2014, deployment totaled only 13.8 MW. One barrier to more rapid deployment is the lack of an incentive specific to CSP, such as a feed-in tariff. The 13th Five Year Plan for Solar Generation (2016-2020), which is under development, presents an opportunity to establish a feed-in tariff specific to CSP. This report, produced under the auspices of the U.S.-China Renewable Energy Partnership, aims to support the development of Chinese incentives that advance CSP deployment goals.

Preliminary experimental study of post-combustion carbon capture integrated with solar thermal collectors

International Nuclear Information System (INIS)

Wang, Fu; Zhao, Jun; Li, Hailong; Deng, Shuai; Yan, Jinyue

2017-01-01

Highlights: • A solar assisted chemical absorption pilot system with two types of collectors (parabolic trough and linear Fresnel reflector) has been constructed. • Performance of two types of solar collectors has been investigated and compared at steady and transient states. • The operations of the pilot system with and without solar assisted have been tested. • The pilot system responds to the temperature of the heat transfer fluid regularly. - Abstract: The amine-based chemical absorption for CO_2 capture normally needs to extract steam from the steam turbine cycle for solvent regeneration. Integrating solar thermal energy enables the reduction of steam extraction and therefore, can reduce the energy penalty caused by CO_2 capture. In this paper, a pilot system of the solar thermal energy assisted chemical absorption was built to investigate the system performance. Two types of solar thermal energy collectors, parabolic trough and linear Fresnel reflector, were tested. It was found that the values of operation parameters can meet the requirements of designed setting parameters, and the solar collectors can provide the thermal energy required by the reboiler, while its contribution was mainly determined by solar irradiation. The solvent regeneration was investigated by varying the heat input. The results show that the response time of the reboiler heat duty is longer than those of the reboiler temperature and desorber pressure. This work provides a better understanding about the overall operation and control of the system.

Comparison of Direct Solar Energy to Resistance Heating for Carbothermal Reduction of Regolith

Science.gov (United States)

Muscatello, Anthony C.; Gustafson, Robert J.

2011-01-01

A comparison of two methods of delivering thermal energy to regolith for the carbo thermal reduction process has been performed. The comparison concludes that electrical resistance heating is superior to direct solar energy via solar concentrators for the following reasons: (1) the resistance heating method can process approximately 12 times as much regolith using the same amount of thermal energy as the direct solar energy method because of superior thermal insulation; (2) the resistance heating method is more adaptable to nearer-term robotic exploration precursor missions because it does not require a solar concentrator system; (3) crucible-based methods are more easily adapted to separation of iron metal and glass by-products than direct solar energy because the melt can be poured directly after processing instead of being remelted; and (4) even with projected improvements in the mass of solar concentrators, projected photovoltaic system masses are expected to be even lower.

Solar energy demonstration zones in the Dalmatian region

Energy Technology Data Exchange (ETDEWEB)

Hrastnik, B. [Energy Institute, Zagreb (Croatia); Frankovic, B. [University of Rijeka (Croatia). Faculty of Engineering

2001-11-01

The energy consumption in the Dalmatian region was estimated for residential and public sector, tourism, commercial sector and industry. The national energy program for the use of solar energy, SUNEN, assessed solar energy potential in Croatia. Energy from fossil fuels and electricity consumption in the region, which is mostly used in households for preparing hot water and space heating, could be economically substituted by renewable energy. The situation is most promising for the islands of the Adriatic, where solar thermal collectors, PV modules and wind generators could substitute conventional energy sources in satisfying the present thermal and electric demand. The Dalmatian Islands, characterised by a small density of energy consumption, are proposed as unique candidates in Europe for renewable zones, which could demonstrate the full potential of the renewable energy option. As a practical demonstration, the island of Lastovo and the planned tourist village and yacht marina in the Bay of Jurjeva Luka are proposed as a first solar demonstration project on the islands. Technical, economic, legal and institutional barriers, as well as shortages of financing the project identification process produced hereto an adverse environment for solar applications in Croatia. This paper is an initiative for eliminating the barriers and intensify the solar energy use in Croatia providing the clean environment and activation of indigenous energy resources in the region. (author)

Solar dryer with thermal storage and biomass-backup heater

Energy Technology Data Exchange (ETDEWEB)

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

2007-04-15

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

Study on the Optimizing Operation of Exhaust Air Heat Recovery and Solar Energy Combined Thermal Compensation System for Ground-Coupled Heat Pump

Directory of Open Access Journals (Sweden)

Kuan Wang

2017-01-01

Full Text Available This study proposed an exhaust air heat recovery and solar energy combined thermal compensation system (ESTC for ground-coupled heat pumps. Based on the prediction of the next day’s exhaust air temperature and solar irradiance, an optimized thermal compensation (OTC method was developed in this study as well, in which the exhaust air heat recovery compensator and solar energy compensator in the ESTC system run at high efficiency throughout various times of day. Moreover, a modified solar term similar days group (STSDG method was proposed to improve the accuracy of solar irradiance prediction in hazy weather. This modified STSDG method was based on air quality forecast and AQI (air quality index correction factors. Through analyzing the operating parameters and the simulation results of a case study, the ESTC system proved to have good performance and high efficiency in eliminating the heat imbalance by using the OTC method. The thermal compensation quantity per unit energy consumption (TEC of ESTC under the proposed method was 1.25 times as high as that under the traditional operation method. The modified STSDG method also exhibited high accuracy. For the accumulated solar irradiance of the four highest daily radiation hours, the monthly mean absolute percentage error (MAPE between the predicted values and the measured values was 6.35%.

Materials compatibility issues related to thermal energy storage for a space solar dynamic power system

Science.gov (United States)

Faget, N. M.

1986-01-01

Attention is given to results obtained to date in developmental investigations of a thermal energy storage (TES) system for the projected NASA Space Station's solar dynamic power system; these tests have concentrated on issues related to materials compatibility for phase change materials (PCMs) and their containment vessels' materials. The five PCMs tested have melting temperatures that correspond to the operating temperatures of either the Brayton or Rankine heat engines, which were independently chosen for their high energy densities.

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

Science.gov (United States)

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

2017-11-01

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

Titanium oxynitrate (TiNxOy) coating for use in thermal solar energy converters

International Nuclear Information System (INIS)

Lasorsa, C; Dilalla, N; Perillo, P; Morando, P.J; Versaci, R; Lucio, R

2008-01-01

This work deals with the production of titanium oxynitrate (TiN x O y ) coatings on metallic substrates. Because of its high resistance to high temperatures, titanium oxynitrate (TiN xO y) is a good material for the production of thermal solar energy converters. The surfaces should possess such qualities as high absorbance (α) of solar radiation (range 0.3 μm ≤λ≤2 μm) and low thermal emittance (ε) in the range of λ≥ 2 μm. The coatings should retain optical qualities temperatures greater than 300 o C. These coatings were made using the PECVD (Plasma Enhanced Chemical Vapor Deposition) technique in a single layer coating, with a gaseous mixture using titanium isopropoxide with an air contribution of reactive gas. The process is developed in one stage, with the substrate thermalized at 750 o C and without y BIAS potential. The coatings were carried out on AISI 410 stainless steel and AISI M2 steel substrates. This work presents the preliminary results of the coating's chemical composition, structure and optical and mechanical properties. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS/ESCA) and scanning electron microscopy were used in these studies

Evaluating Different Green School Building Designs for Albania: Indoor Thermal Comfort, Energy Use Analysis with Solar Systems

Science.gov (United States)

Dalvi, Ambalika Rajendra

Improving the conditions of schools in many parts of the world is gradually acquiring importance. The Green School movement is an integral part of this effort since it aims at improving indoor environmental conditions. This would in turn, enhance student- learning while minimizing adverse environmental impact through energy efficiency of comfort-related HVAC and lighting systems. This research, which is a part of a larger research project, aims at evaluating different school building designs in Albania in terms of energy use and indoor thermal comfort, and identify energy efficient options of existing schools. We start by identifying three different climate zones in Albania; Coastal (Durres), Hill/Pre-mountainous (Tirana), mountainous (Korca). Next, two prototypical school building designs are identified from the existing stock. Numerous scenarios are then identified for analysis which consists of combinations of climate zone, building type, building orientation, building upgrade levels, presence of renewable energy systems (solar photovoltaic and solar water heater). The existing building layouts, initially outlined in CAD software and then imported into a detailed building energy software program (eQuest) to perform annual simulations for all scenarios. The research also predicted indoor thermal comfort conditions of the various scenarios on the premise that windows could be opened to provide natural ventilation cooling when appropriate. This study also estimated the energy generated from solar photovoltaic systems and solar water heater systems when placed on the available roof area to determine the extent to which they are able to meet the required electric loads (plug and lights) and building heating loads respectively. The results showed that there is adequate indoor comfort without the need for mechanical cooling for the three climate zones, and that only heating is needed during the winter months.

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

Energy Technology Data Exchange (ETDEWEB)

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

1980-03-01

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

Experimental study on comprehensive utilization of solar energy and energy balance in an integrated solar house

International Nuclear Information System (INIS)

Chang, Huawei; Liu, Yuting; Shen, Jinqiu; Xiang, Can; He, Sinian; Wan, Zhongmin; Jiang, Meng; Duan, Chen; Shu, Shuiming

2015-01-01

Highlights: • Active and passive solar house technology is integrated in the solar house. • Solar thermal system and solar photoelectric system are measured and analyzed. • Energy balance and energy consumption are analyzed with valuable experimental data. • “Zero energy consumption” is truly achieved with the solar supply rate of 1.19 in winter. - Abstract: An integrated solar house with numerous advanced envelops is designed and constructed to investigate the comprehensive utilization of solar energy, energy efficiency and energy balance, which combines active solar house technology with passive solar house technology including solar photovoltaic system, solar water heating system, direct-gain door and windows. Solar radiation intensity, performance of the photovoltaic system, water temperature, and indoor and outdoor temperature are measured, results of the experiments indicate that solar glass window on the south wall can maintain the average indoor temperature at 21.4 °C in the case of average outdoor temperature at 11.2 °C without any external heat supply. The output current of the solar photovoltaic system shows the same trend as solar radiation intensity. When the intensity is 619.7 W/m"2, the instantaneous generation power could reach a value of 781.9 W, cumulative capacity throughout the day achieves 4.56 kW h and photovoltaic conversion efficiency 9.8%. When the average intensity throughout a day is 358 W/m"2, the solar water heating system could help to raise the temperature of 450 L water by 30 °C with its heat collecting efficiency being 37.4%. Through the analysis of the overall energy system in the solar house, it can be derived that this solar house could achieve “zero energy consumption” in winter with the solar supply rate at 1.19.

Summary Report for Concentrating Solar Power Thermal Storage Workshop: New Concepts and Materials for Thermal Energy Storage and Heat-Transfer Fluids, May 20, 2011

Energy Technology Data Exchange (ETDEWEB)

Glatzmaier, G.

2011-08-01

This document summarizes a workshop on thermal energy storage for concentrating solar power (CSP) that was held in Golden, Colorado, on May 20, 2011. The event was hosted by the U.S. Department of Energy (DOE), the National Renewable Energy Laboratory, and Sandia National Laboratories. The objective was to engage the university and laboratory research communities to identify and define research directions for developing new high-temperature materials and systems that advance thermal energy storage for CSP technologies. This workshop was motivated, in part, by the DOE SunShot Initiative, which sets a very aggressive cost goal for CSP technologies -- a levelized cost of energy of 6 cents per kilowatt-hour by 2020 with no incentives or credits.

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

Directory of Open Access Journals (Sweden)

Deepak Bishoyi

2017-09-01

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

Solar thermal power and photovoltaic energy are both developing

International Nuclear Information System (INIS)

Le Jannic, N.; Houot, G.

2010-01-01

Thermodynamic solar energy and photovoltaic energy are expected to reach together a quarter of the world electricity production by 2050. In France the development of thermodynamic solar plants is hampered by the high cost of land in the sunny regions. As for photovoltaic energy, France has the potentiality to become an important producer. Since 2006, the French government has supported photovoltaic energy by proposing incentive electricity purchase prices guaranteed for 20 years. In 2006, the Ines research institute was founded, one of its research fields is the development of high yield silicon cells. (A.C.)

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

Directory of Open Access Journals (Sweden)

Wisut Chamsa-ard

2017-05-01

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

Numerical simulation of thermal behaviors of a clothed human body with evaluation of indoor solar radiation

International Nuclear Information System (INIS)

Mao, Aihua; Luo, Jie; Li, Yi

2017-01-01

Highlights: • Solar radiation evaluation is integrated with the thermal transfer in clothed humans. • Thermal models are developed for clothed humans exposed in indoor solar radiation. • The effect of indoor solar radiation on humans can be predicted in different situations in living. • The green solar energy can be efficiently utilized in the building development. - Abstract: Solar radiation is a valuable green energy, which is important in achieving a successful building design for thermal comfort in indoor environment. This paper considers solar radiation indoors into the transient thermal transfer models of a clothed human body and offers a new numerical method to analyze the dynamic thermal status of a clothed human body under different solar radiation incidences. The evaluation model of solar radiation indoors and a group of coupled thermal models of the clothed human body are developed and integrated. The simulation capacities of these integrated models are validated through a comparison between the predicted results and the experimental data in reference. After that, simulation cases are also conducted to show the influence of solar radiation on the thermal status of individual clothed body segments when the human body is staying indoors in different seasons. This numerical simulation method provides a useful tool to analyze the thermal status of clothed human body under different solar radiation incidences indoors and thus enables the architect to efficiently utilize the green solar energy in building development.

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

KAUST Repository

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

2016-01-01

is the intermittent nature of solar irradiation, which makes them unable to stand-alone to satisfy continuous energy need. Herein, we report a three-dimensional (3D) graphene foam and phase change material (PCM) composite for the seamlessly combined solar

Solar 92: The 1992 American Solar Energy Society annual conference

International Nuclear Information System (INIS)

Burley, S.; Arden, M.E.

1992-01-01

The purpose of this symposium is to document the lessons learned from federal and state policies and programs in the late 1970's and 1980's aimed at promoting consumer use of solar energy. During this period the primary emphasis was on solar thermal technologies and passive solar design that could be used at the residential level, though there was also some information on stand-alone photovoltaic systems as well

Estimation of monthly solar radiation distribution for solar energy system analysis

International Nuclear Information System (INIS)

Coskun, C.; Oktay, Z.; Dincer, I.

2011-01-01

The concept of probability density frequency, which is successfully used for analyses of wind speed and outdoor temperature distributions, is now modified and proposed for estimating solar radiation distributions for design and analysis of solar energy systems. In this study, global solar radiation distribution is comprehensively analyzed for photovoltaic (PV) panel and thermal collector systems. In this regard, a case study is conducted with actual global solar irradiation data of the last 15 years recorded by the Turkish State Meteorological Service. It is found that intensity of global solar irradiance greatly affects energy and exergy efficiencies and hence the performance of collectors. -- Research highlights: → The first study to apply global solar radiation distribution in solar system analyzes. → The first study showing global solar radiation distribution as a parameter of the solar irradiance intensity. → Time probability intensity frequency and probability power distribution do not have similar distribution patterns for each month. → There is no relation between the distribution of annual time lapse and solar energy with the intensity of solar irradiance.

Solar energy utilization in the USSR

International Nuclear Information System (INIS)

Shpil'rajn, Eh.Eh.

1993-01-01

The conditions for solar energy utilization in the USSR are not too favorable. Only in the country's southern regions is there sufficient insolation to make solar energy utilization economical. In higher latitudes only seasonable use of solar energy is reasonable. Up to now, the main application of solar energy was to produce low temperature heat for hot water production, drying of agricultural goods, space heating and thermal treating of concrete. A substantial part of the solar heating installations is flat plate solar collectors. The total installed area of solar collectors slightly exceeds 100,000 m 2 . The collectors are produced by industry, as well as by small enterprises. In some cases selective coatings are used over the absorber plates; black nickel or chromium is the main coating material. Recently, new projects were launched to develop and produce advanced collectors with enhanced efficiency and reliability. Substantial progress has been made in the USSR in developing and producing photovoltaic cells, mainly for space applications. Terrestrial applications of photovoltaic is only in the very early stage. About 100 Kw of photovoltaic cells are produced annually in the USSR, based on mono or polycrystalline silicon. Some experimental photovoltaic-arrays in the range of several tenth of Kw are installed in different places. Research and development work is carried out to produce thin film cells. Effort are in progress to construct automated production lines for 1 MW per year of crystalline and amorphous silicon. In the Crimea, a solar power plant SES-5 (5 MW peak power) was commissioned some years ago. The plant is of a tower type, with a circular helioscope field. The plants working fluid is steam. The experienced gained demonstrates that this design concept has several disadvantages. The cost of electricity produced by such type plants extremely high. Recently, alternative types of solar power plants have been under development, in particular, a project

Solar thermal technology and market in Europe

International Nuclear Information System (INIS)

Sabba, S.

2000-01-01

The solar heating industry in Europe has reached maturity after more than two decades of technical development. High quality systems are now available with reliability and durability of the products being assured. The European solar market, now the world's largest, has been growing since the late 1980s, despite the fact that conventional energy sources are usually available and inexpensive. This is a new phenomenon and marks the beginning of changes in energy supply and consumption that will be experienced throughout the world in this new century. Almost 10 million square metres of solar thermal collectors now exist in Europe saving more than 1.5 million tonnes of CO 2 emissions and about 500,000 tonnes of oil. The solar heating industry has created some 10,000 jobs. (author)

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

Directory of Open Access Journals (Sweden)

M Mohammadi Sarduei

2017-05-01

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

A novel application of concentrated solar thermal energy in foundries.

Science.gov (United States)

Selvaraj, J; Harikesavan, V; Eshwanth, A

2016-05-01

Scrap preheating in foundries is a technology that saves melting energy, leading to economic and environmental benefits. The proposed method in this paper utilizes solar thermal energy for preheating scrap, effected through a parabolic trough concentrator that focuses sunlight onto a receiver which carries the metallic scrap. Scraps of various thicknesses were placed on the receiver to study the heat absorption by them. Experimental results revealed the pattern with which heat is gained by the scrap, the efficiency of the process and how it is affected as the scrap gains heat. The inferences from them gave practical guidelines on handling scraps for best possible energy savings. Based on the experiments conducted, preheat of up to 160 °C and a maximum efficiency of 70 % and a minimum efficiency of 40 % could be achieved across the time elapsed and heat gained by the scrap. Calculations show that this technology has the potential to save around 8 % of the energy consumption in foundries. Cumulative benefits are very encouraging: 180.45 million kWh of energy savings and 203,905 t of carbon emissions cut per year across the globe. This research reveals immense scope for this technology to be adopted by foundries throughout the world.

Characteristics Study of Photovoltaic Thermal System with Emphasis on Energy Efficiency

Directory of Open Access Journals (Sweden)

Yong Chuah Yee

2018-01-01

Full Text Available Solar energy is typically collected through photovoltaic (PV to generate electricity or through thermal collectors as heat energy, they are generally utilised separately. This project is done with the purpose of integrating the two systems to improve the energy efficiency. The idea of this photovoltaic-thermal (PVT setup design is to simultaneously cool the PV panel so it can operate at a lower temperature thus higher electrical efficiency and also store the thermal energy. The experimental data shows that the PVT setup increased the electrical efficiency of the standard PV setup from 1.64% to 2.15%. The integration of the thermal collector also allowed 37.25% of solar energy to be stored as thermal energy. The standard PV setup harnessed only 1.64% of the solar energy, whereas the PVT setup achieved 39.4%. Different flowrates were tested to determine its effects on the PVT setup’s electrical and thermal efficiency. The various flowrate does not significantly impact the electrical efficiency since it did not significantly impact the cooling of the panel. The various flowrates resulted in fluctuating thermal efficiencies, the relation between the two is inconclusive in this project.

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

Energy Technology Data Exchange (ETDEWEB)

Licht, S. [Department of Chemistry, George Washington University, Washington, DC (United States)

2011-12-15

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

Solar Thermal | Climate Neutral Research Campuses | NREL

Science.gov (United States)

building can still be designed and constructed to be solar ready with roof exposures and slopes that accept Solar Thermal Solar Thermal Solar thermal applications can be simple, cost effective, and diverse for research campuses. The following links go to sections that describe when and where solar thermal

Potency of Solar Energy Applications in Indonesia

Directory of Open Access Journals (Sweden)

Noer Abyor Handayani

2012-07-01

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

Solar thermal barometer

International Nuclear Information System (INIS)

Anon.

2010-01-01

In 2008, the European solar thermal market put on a strong spurt only to mark time in 2009 with about 4.2 million m 2 installed, which is 450000 m 2 less year-on-year. The main reasons of the decrease is the financial crisis and the low oil price, other reasons more specific to the country exist, for instance the property crisis has dragged the Spanish market down. In 2009, the solar thermal collector surface area in service in the European Union is of the magnitude of 32.6 million m 2 , equivalent to a capacity of 22.8 GWTh. The solar thermal sector is one of the renewable sectors that creates the highest number of jobs and wealth, partly because the vast majority of the system components sold in Europe are produced in Europe and partly because the sale, installation fitting and maintenance are labour-intensive. In 2009, there were 50000 direct or indirect jobs in the European solar thermal sector. The main European actors in this sector are GREENoneTEC, Bosch-Thermotechnik, Viessmann, Vaillant and Solvis. No clear recovery is expected before 2011. (A.C.)

Quarterly overviews of thermal solar energy systems 1993

International Nuclear Information System (INIS)

Warmerdam, J.M.; Stap, C.A.M.

1994-08-01

The title overviews were compiled to support the market introduction campaign for solar water heaters in the Netherlands. Use has been made of the data-banks of the Dutch subsidy administrator 'Senter'. 88% of the 1,883 systems, that were installed in 1993, are solar water heaters. Considering the solar collector surface the largest contribution is from the use of mainly uncovered collectors in swimming pools: 51% (37% for the collector surface of solar water heaters). Energy utilities are involved in the installation of 70% of the solar heating systems (even 77% for the solar water heaters). Next to the quarterly overviews, the subsidy data for the period 1988 up to and including 1993 are analyzed. 70% of the installed systems has been purchased and 30% was rented. At the end of 1993 preparations were made to install more than 3,000 solar boilers in 1994 and 1995. 3 figs., 21 tabs

Preparation and characterization of molten salt based nanothermic fluids with enhanced thermal properties for solar thermal applications

International Nuclear Information System (INIS)

Madathil, Pramod Kandoth; Balagi, Nagaraj; Saha, Priyanka; Bharali, Jitalaxmi; Rao, Peddy V.C.; Choudary, Nettem V.; Ramesh, Kanaparthi

2016-01-01

Highlights: • Prepared and characterized inorganic ternary molten salt based nanothermic fluids. • MoS_2 and CuO nanoparticles incorporated ternary molten salts have been prepared. • Thermal properties enhanced by the addition of MoS_2 and CuO nanoparticles. • The amount of nanoparticles has been optimized. - Abstract: In the current energy scenario, solar energy is attracting considerable attention as a renewable energy source with ample research and commercial opportunities. The novel and efficient technologies in the solar energy are directed to develop methods for solar energy capture, storage and utilization. High temperature thermal energy storage systems can deal with a wide range of temperatures and therefore they are highly recommended for concentrated solar power (CSP) applications. In the present study, a systematic investigation has been carried out to identify the suitable inorganic nanoparticles and their addition in the molten salt has been optimized. In order to enhance the thermo-physical properties such as thermal conductivity and specific heat capacity of molten salt based HTFs, we report the utilization of MoS_2 and CuO nanoparticles. The enhancement in the above mentioned thermo-physical properties has been demonstrated for optimized compositions and the morphologies of nanoparticle-incorporated molten salts have been studied by scanning electron microscopy (SEM). Nanoparticle addition to molten salts is an efficient method to prepare thermally stable molten salt based heat transfer fluids which can be used in CSP plants. It is also observed that the sedimentation of nanoparticles in molten salt is negligible compared to that in organic heat transfer fluids.

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.

High Performance Flat Plate Solar Thermal Collector Evaluation

Energy Technology Data Exchange (ETDEWEB)

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

2016-09-01

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

Comparison of selective transmitters for solar thermal applications.

Science.gov (United States)

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

2016-05-10

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

Thermal-CFD Analysis of Combined Solar-Nuclear Cycle Systems.

Energy Technology Data Exchange (ETDEWEB)

Fathi, Nima [Univ. of New Mexico, Albuquerque, NM (United States); McDaniel, Patrick [Univ. of New Mexico, Albuquerque, NM (United States); Vorobieff, Peter [Univ. of New Mexico, Albuquerque, NM (United States); de Oliveira, Cassiano [Univ. of New Mexico, Albuquerque, NM (United States); Rodriguez, Salvador B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Aleyasin, Seyed Sobhan [Univ. of Manitoba (Canada)

2015-09-01

The aim of this paper is evaluating the efficiency of a novel combined solar-nuclear cycle. CFD-Thermal analysis is performed to apply the available surplus heat from the nuclear cycle and measure the available kinetic energy of air for the turbine of a solar chimney power plant system (SCPPS). The presented idea helps to decrease the thermal pollution and handle the water shortage supply for water plant by replacing the cooling tower by solar chimney power plant to get the surplus heat from the available warm air in the secondary loop of the reactor. By applying this idea to a typical 1000 MW nuclear power plant with a 0.33 thermal efficiency, we can increase it to 0.39.

Thermal characterization of nitrates and nitrates/expanded graphite mixture phase change materials for solar energy storage

International Nuclear Information System (INIS)

Xiao, X.; Zhang, P.; Li, M.

2013-01-01

Highlights: • The addition of expanded graphite improved apparent thermal conductivity significantly. • The quadratic parallel model was used to predict the effective thermal conductivity. • The melting/freezing temperatures of mixture PCMs shifted slightly with adding of EG. - Abstract: Solar energy storage has become more attractive in recent years. In particular, latent thermal energy storage (LTES) with large energy storage density and isothermal heat storage/retrieval characteristics is a hot research topic. In the present study, sodium nitrate, potassium nitrate and their mixture were used as the base materials, and expanded graphite (EG) with high thermal conductivity and thermo-chemical stability was used as an additive to enhance the thermal conductivity. EG with various mass fractions was added to the base materials to form mixture phase change materials (PCMs), and the thermal characteristics of the mixtures were studied extensively. The transient hot-wire tests showed that the addition of EG enhanced the apparent thermal conductivity significantly, e.g. the apparent thermal conductivity of the nitrates/10 wt.% EG mixture PCM was increased by about 30–40%. The test results showed good agreement with theoretical calculations of the quadratic parallel model. Tests with differential scanning calorimeter (DSC) revealed that the melting/freezing temperatures of the mixture PCMs shifted slightly, compared with those of pure nitrates

Economical and environmental analysis of thermal and photovoltaic solar energy as source of heat for industrial processes

Science.gov (United States)

Pérez-Aparicio, Elena; Lillo-Bravo, Isidoro; Moreno-Tejera, Sara; Silva-Pérez, Manuel

2017-06-01

Thermal energy for industrial processes can be generated using thermal (ST) or photovoltaic (PV) solar energy. ST energy has traditionally been the most favorable option due to its cost and efficiency. Current costs and efficiencies values make the PV solar energy become an alternative to ST energy as supplier of industrial process heat. The aim of this study is to provide a useful tool to decide in each case which option is economically and environmentally the most suitable alternative. The methodology used to compare ST and PV systems is based on the calculation of the levelized cost of energy (LCOE) and greenhouse gas emissions (GHG) avoided by using renewable technologies instead of conventional sources of energy. In both cases, these calculations depend on costs and efficiencies associated with ST or PV systems and the conversion factor from thermal or electrical energy to GHG. To make these calculations, a series of hypotheses are assumed related to consumer and energy prices, operation, maintenance and replacement costs, lifetime of the system or working temperature of the industrial process. This study applies the methodology at five different sites which have been selected taking into account their radiometric and meteorological characteristics. In the case of ST energy three technologies are taken into account, compound parabolic concentrator (CPC), linear Fresnel collector (LFC) and parabolic trough collector (PTC). The PV option includes two ways of use of generated electricity, an electrical resistance or a combination of an electrical resistance and a heat pump (HP). Current values of costs and efficiencies make ST system remains as the most favorable option. These parameters may vary significantly over time. The evolution of these parameters may convert PV systems into the most favorable option for particular applications.

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

OpenAIRE

M. Z. H. Khan; M. R. Al-Mamun; S. Sikdar; P. K. Halder; M. R. Hasan

2016-01-01

This paper investigated a novel loop-heat-pipe based solar thermal heat-pump system for small scale hot water production for household purposes. The effective use of solar energy is hindered by the intermittent nature of its availability, limiting its use and effectiveness in domestic and industrial applications especially in water heating. The easiest and the most used method is the conversion of solar energy into thermal energy. We developed a prototype solar water heating system for experi...

Solar Energy as an Alternative to Energy Saving and Pollutant Emissions Reduction

Directory of Open Access Journals (Sweden)

Arina Negoițescu

2016-10-01

Full Text Available In the paper is analyzed thermal solar systems efficiency from the point of view of energy savings and pollutant emissions concentrations exhausted during these installations operation. For this purpose were taking into account four versions of solar panel systems combined with different types of conventional heating sources, for which were simulated the operation conditions. As a result of the simulation, there were obtained the values of energy savings and pollutant emissions during the four systems operation. By analyzing these values, the combined thermal system optimum solution was selected.

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

Directory of Open Access Journals (Sweden)

M. Z. H. Khan

2016-01-01

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

High-energy, stable and recycled molecular solar thermal storage materials using AZO/graphene hybrids by optimizing hydrogen bonds.

Science.gov (United States)

Luo, Wen; Feng, Yiyu; Qin, Chengqun; Li, Man; Li, Shipei; Cao, Chen; Long, Peng; Liu, Enzuo; Hu, Wenping; Yoshino, Katsumi; Feng, Wei

2015-10-21

An important method for establishing a high-energy, stable and recycled molecular solar heat system is by designing and preparing novel photo-isomerizable molecules with a high enthalpy and a long thermal life by controlling molecular interactions. A meta- and ortho-bis-substituted azobenzene chromophore (AZO) is covalently grafted onto reduced graphene oxide (RGO) for solar thermal storage materials. High grafting degree and close-packed molecules enable intermolecular hydrogen bonds (H-bonds) for both trans-(E) and cis-(Z) isomers of AZO on the surface of nanosheets, resulting in a dramatic increase in enthalpy and lifetime. The metastable Z-form of AZO on RGO is thermally stabilized with a half-life of 52 days by steric hindrance and intermolecular H-bonds calculated using density functional theory (DFT). The AZO-RGO fuel shows a high storage capacity of 138 Wh kg(-1) by optimizing intermolecular H-bonds with a good cycling stability for 50 cycles induced by visible light at 520 nm. Our work opens up a new method for making advanced molecular solar thermal storage materials by tuning molecular interactions on a nano-template.

Housing and sustainable development: perspectives offered by thermal solar energy. Particle emissions: prospective investigation of primary particle emissions in France by 2030

International Nuclear Information System (INIS)

Brignon, J.M.; Cauret, L.; Sambat, S.

2004-09-01

This publication proposes two investigation reports. A first study proposes a prospective analysis of the housing 'stock' in France and the evolution of global energy consumptions and CO 2 emissions by the housing sector, a prospective study of space heating and hot water needs by defining reference scenarios as well as a target scenario for heating consumption (based on the factor 4 of reduction of emissions by 2050), and an assessment of the contribution of the thermal solar energy applied to winter comfort under the form of direct solar floors and passive solar contributions, and applied to hot water by 2050. The contribution of the thermal solar energy is studied within its regulatory context. An analysis of urban forms is also performed to assess the potential of integration of renewable energy solutions in the existing housing stock, and thus to assess the morphological limits of an attempt of generalized solarization of roofs. The second study proposes a detailed identification and assessment of the various sources of primary particles (combustion, industrial processes, mineral extraction and processing, road transport, waste processing and elimination, agriculture, natural sources, forest fires), providing more precise results and methodological complements for some sources. It also proposes a prospective assessment of emissions and identifies the main factors of particle concentrations in urban environment

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

Science.gov (United States)

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

2011-07-01

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

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

Science.gov (United States)

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

2011-05-01

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

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