Explore the performance limit of a solar PV – thermochemical power generation system

International Nuclear Information System (INIS)

Li, Wenjia; Hao, Yong

2017-01-01

Highlights: •Theoretical net solar-to-electric efficiency of 51.5% is attainable. •Design of efficient PVT systems is governed by at least 5 key considerations. •Concentration ratio has the most pronounced influence on PVT system efficiency. •Efficient PV, low emissivity and high concentration deliver the best performance. -- Abstract: Performance limit of a solar hybrid power generation system integrating efficient photovoltaic (PV) cells and methanol thermal (T) decomposition is explored from a thermodynamic perspective within the capability of state-of-the-art technologies. This type of PVT system features potentially high “net solar-to-electric efficiency” in general, primarily resulting from a key difference in the design of the thermal part compared with conventional PVT systems, i.e. replacing heat engines by a thermochemical power generation module for thermal energy utilization. Key design parameters of the system, including PV cell type, emissivity, solar concentration ratio and solar concentrator type, are individually studied. A system combining all such optimized aspects is projected to achieve net solar-to-electric efficiencies up to 51.5%, after taking all major (e.g. optical, radiative) losses into consideration. This study reveals important insights and enriches understanding on design principles of efficient PVT systems aimed at comprehensive and effective utilization of solar energy.

Next-Generation Ultra-Compact Stowage/Lightweight Solar Array System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Deployable Space Systems, Inc. (DSS) has developed a next-generation high performance solar array system that has game-changing performance metrics in terms of...

Solar generators in terrestrial communication technology. Pt. 1

Energy Technology Data Exchange (ETDEWEB)

Sommer, E

1978-01-01

To begin with, the basic terms solar cell, solar cell module, solar generator, and solar generator system are defined and illustrated by examples. After this, the advantages and disadvantages of solar generators in power supply for terrestrial communications as compared to dry cell batteries, diesel generators and mains operation are discussed with a view to technical, economic, and ecological aspects. After some hints for an optimum design of systems, a comprehensive, general list of possible applications is given. The second part will give a detailed description of typical and exemplary applications.

Solar engine system

International Nuclear Information System (INIS)

Tan, K.K.; Bahrom Sanugi; Chen, L.C.; Chong, K.K.; Jasmy Yunus; Kannan, K.S.; Lim, B.H.; Noriah Bidin; Omar Aliman; Sahar Salehan; Sheikh Ab Rezan Sheikh A H; Tam, C.M.; Chen, Y.T.

2001-01-01

This paper reports the revolutionary solar engine system in Universiti Teknologi Malaysia (UTM). The solar engine is a single cylinder stirling engine driven by solar thermal energy. A first prototype solar engine has been built and demonstrated. A new-concept non-imaging focusing heliostat and a recently invented optical receiver are used in the demonstration. Second generation of prototype solar engine is described briefly. In this paper, the solar engine system development is reported. Measurement for the first prototype engine speed, temperature and specifications are presented. The benefits and potential applications for the future solar engine system, especially for the electricity generating aspect are discussed. (Author)

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)

Investigation of Solar Hybrid Electric/Thermal System with Radiation Concentrator and Thermoelectric Generator

Directory of Open Access Journals (Sweden)

Edgar Arturo Chávez Urbiola

2013-01-01

Full Text Available An experimental study of a solar-concentrating system based on thermoelectric generators (TEGs was performed. The system included an electrical generating unit with 6 serially connected TEGs using a traditional semiconductor material, Bi2Te3, which was illuminated by concentrated solar radiation on one side and cooled by running water on the other side. A sun-tracking concentrator with a mosaic set of mirrors was used; its orientation towards the sun was achieved with two pairs of radiation sensors, a differential amplifier, and two servomotors. The hot side of the TEGs at midday has a temperature of around 200°C, and the cold side is approximately 50°C. The thermosiphon cooling system was designed to absorb the heat passing through the TEGs and provide optimal working conditions. The system generates 20 W of electrical energy and 200 W of thermal energy stored in water with a temperature of around 50°C. The hybrid system studied can be considered as an alternative to photovoltaic/thermal systems, especially in countries with abundant solar radiation, such as Mexico, China, and India.

Trend of development of dispersion energy machine. Solar power generation system; Taiyoko hatsuden shisutemu

Energy Technology Data Exchange (ETDEWEB)

Oda, T. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

2000-04-01

Technology development of a solar power generation system is advanced in Japan taking the New Sunshine Subject (NSS) of the Agency of Industrial Science and Technology as the center. According to the initial stage plan (in fiscal 1993 to 2000) of the NSS, a general goal is to establish the technique which supplies electric power at the power generating cost (the production base cost) being equal to the electricity fees (20 to 30 yen/kWh) for normal families in the latest year. At present, introduction of the solar power generation system results in the reduction of about 1 million yen per kW. It is expected that 5 hundred thousand yen per kW is reduced by the present technology with a combination of cost reduction of solar battery modules, cost reduction of relevant equipment such as inverters, and rationalization of installation fees. It is necessary to realize 3 hundred thousand yen per kW for realizing the price having competition in the power supply market. In this paper, popularization prediction and popularization promotion countermeasures of the solar power generation system are concretely explained. (NEDO)

Development of solar power generator system; Taiyoko netsufukugo hatsuden system no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Kisara, K; Kumagai, T; Niino, M; Chen, L; Eguchi, K [National Aerospace Laboratory, Tokyo (Japan)

1997-11-25

Described herein is a new hybrid solar power generator system, in which solar energy is separated into the light and heat components by a wavelength-selective filter before being directly converted into electric power, the former for the amorphous solar cell (ASC) unit and the latter for the thermoelectric unit. These units complement with each other to enhance overall efficiency. The ASC unit should have a higher efficiency when it works on the light component, because the heat (infrared) component increases cell temperature and decreases its output. For the ASC unit, the effects of the filter have been tested. The thermoelectric unit, generating power by the Seebeck effect, should have a higher efficiency, if heat flux passing through the unit can be increased, because of increased temperature differential, to which voltage produced increases proportionally. For the thermoelectric unit, heat is collected by a parabolic mirror unit from sunbeams received by a heliostat. Characteristics of these units are grasped almost as expected by the tests. 4 refs., 11 figs., 1 tab.

Passive flow heat exchanger simulation for power generation from solar pond using thermoelectric generators

Science.gov (United States)

Baharin, Nuraida'Aadilia; Arzami, Amir Afiq; Singh, Baljit; Remeli, Muhammad Fairuz; Tan, Lippong; Oberoi, Amandeep

2017-04-01

In this study, a thermoelectric generator heat exchanger system was designed and simulated for electricity generation from solar pond. A thermoelectric generator heat exchanger was studied by using Computational Fluid Dynamics to simulate flow and heat transfer. A thermoelectric generator heat exchanger designed for passive in-pond flow used in solar pond for electrical power generation. A simple analysis simulation was developed to obtain the amount of electricity generated at different conditions for hot temperatures of a solar pond at different flow rates. Results indicated that the system is capable of producing electricity. This study and design provides an alternative way to generate electricity from solar pond in tropical countries like Malaysia for possible renewable energy applications.

Solar thermoelectric generator

Science.gov (United States)

Toberer, Eric S.; Baranowski, Lauryn L.; Warren, Emily L.

2016-05-03

Solar thermoelectric generators (STEGs) are solid state heat engines that generate electricity from concentrated sunlight. A novel detailed balance model for STEGs is provided and applied to both state-of-the-art and idealized materials. STEGs can produce electricity by using sunlight to heat one side of a thermoelectric generator. While concentrated sunlight can be used to achieve extremely high temperatures (and thus improved generator efficiency), the solar absorber also emits a significant amount of black body radiation. This emitted light is the dominant loss mechanism in these generators. In this invention, we propose a solution to this problem that eliminates virtually all of the emitted black body radiation. This enables solar thermoelectric generators to operate at higher efficiency and achieve said efficient with lower levels of optical concentration. The solution is suitable for both single and dual axis solar thermoelectric generators.

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. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1980-03-01

In connection with the practicability of a solar thermal power generation system, examination was made on the technical economic problems and the operation method as well as on the problems of required performance of the constituent equipment, with the measuring method and performance evaluation method examined that are suitable for various devices. The items for the examination are as follows: (1) Silicon as the raw material for solar cells and its R and D, (2) Amorphous silicon solar cells, (3) R and D on low cost solar cells and array, (4) Basic design for photovoltaic generation system, and (5) Problems and technical subjects for solar cell standard measurement. The research themes and items for the above examination are listed as below: (1) Demand trend for raw material silicon, overseas trend, and development plan for polycrystalline silicon; (2) R and D plan for amorphous Si solar cell and its system, their optimum design, and their cost analysis and economic effect; (3) Technological investigation on cells and examination on array; (4) Basic design, peripheral equipment for system, and development schedule; (5) Report on the first actual state investigation concerning instrumentation of solar cells, i.e., on 'instrumentation and deviation in transformation efficiency', calibration system, problems of instrumentation of new device, problems of reliability test method, situation in various countries, and trend in atmospheric turbidimeter. (NEDO)

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. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1980-03-01

In connection with the practicability of a solar thermal power generation system, examination was made on the technical economic problems and the operation method as well as on the problems of required performance of the constituent equipment, with the measuring method and performance evaluation method examined that are suitable for various devices. The items for the examination are as follows: (1) Silicon as the raw material for solar cells and its R and D, (2) Amorphous silicon solar cells, (3) R and D on low cost solar cells and array, (4) Basic design for photovoltaic generation system, and (5) Problems and technical subjects for solar cell standard measurement. The research themes and items for the above examination are listed as below: (1) Demand trend for raw material silicon, overseas trend, and development plan for polycrystalline silicon; (2) R and D plan for amorphous Si solar cell and its system, their optimum design, and their cost analysis and economic effect; (3) Technological investigation on cells and examination on array; (4) Basic design, peripheral equipment for system, and development schedule; (5) Report on the first actual state investigation concerning instrumentation of solar cells, i.e., on 'instrumentation and deviation in transformation efficiency', calibration system, problems of instrumentation of new device, problems of reliability test method, situation in various countries, and trend in atmospheric turbidimeter. (NEDO)

Solar photovoltaic system design optimization by shading analysis to maximize energy generation from limited urban area

International Nuclear Information System (INIS)

Rachchh, Ravi; Kumar, Manoj; Tripathi, Brijesh

2016-01-01

Highlights: • Scheme to maximize total number of solar panels in a given area. • Enhanced energy output from a fixed area without compromising the efficiency. • Capacity and generated energy are enhanced by more than 25%. - Abstract: In the urban areas the demand of solar power is increasing due to better awareness about the emission of green house gases from conventional thermal power plants and significant decrease in the installation cost of residential solar power plants. But the land cost and the under utilization of available space is hindering its further growth. Under these circumstances, solar photovoltaic system installation needs to accommodate the maximum number of solar panels in either roof-top or land-mounted category. In this article a new approach is suggested to maximize the total number of solar panels in a given area with enhanced energy output without compromising the overall efficiency of the system. The number of solar panels can be maximized in a solar photovoltaic energy generation system by optimizing installation parameters such as tilt angle, pitch, gain factor, altitude angle and shading to improve the energy yield. In this paper mathematical analysis is done to show that the capacity and generated energy can be enhanced by more than 25% for a given land area by optimization various parameters.

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)

Environmental aspects of electricity generation from a nanocrystalline dye sensitized solar cell system

International Nuclear Information System (INIS)

Greijer, Helena; Karlson, Lennart; Lindquist, Sten-Eric; Hagfeldt, Anders

2001-01-01

A Life Cycle Assessment, LCA, of a nanocrystalline dye sensitised solar cell (ncDSC) system has been performed, according to the ISO14040 standard. In brief, LCA is a tool to analyse the total environment impact of a product or system from cradle to grave. Six different weighing methods were used to rank and select the significant environmental aspects to study further. The most significant environmental aspects according to the weighing methods are emission of sulphur dioxide and carbon dioxide. Carbon dioxide emission was selected as the environmental indicator depending on the growing attention on the global warming effect. In an environmental comparison of electricity generation from a ncDSC system and a natural gas/combined cycle power plant, the gas power plant would result in 450 g CO 2 /kWh and the ncDSC system in between 19-47 g CO 2 /wWh. The latter can be compared with 42 g CO 2 /kWh, according to van Brummelen et al. 'Life Cycle Assessment of Roof Integrated Solar Cell Systems, (Report: Department of Science, Technology and Society, Utrecht University, The Netherlands, 1994)' for another thin film solar cell system made of amorphous silicon. The most significant activity/component contributing to environmental impact over the life cycle of the ncDSC system is the process energy for producing the solar cell module. Secondly comes the components; glass substrate, frame and junction box. The main improvement from an environmental point of view of the current technology would be an increase in the conversion efficiency from solar radiation to electricity generation and still use low energy demanding production technologies. Also the amount of material in the solar cell system should be minimised and designed to maximise recycling. (Author)

Hybrid power system (hydro, solar and wind) for rural electricity generation

International Nuclear Information System (INIS)

Mahinda Kurukulasuriya

2000-01-01

Generation of affordable cheap electric energy for rural development by a hybrid power system (10-50 kW) of hydropower, solar and wind energies on self determining basis and computer application to determine its performance. In this paper the following topics were discussed, design of hybrid power system, its justification and economic analysis, manufacturing and installation of the system. (Author)

Optimal Solar PV Arrays Integration for Distributed Generation

Energy Technology Data Exchange (ETDEWEB)

Omitaomu, Olufemi A [ORNL; Li, Xueping [University of Tennessee, Knoxville (UTK)

2012-01-01

Solar photovoltaic (PV) systems hold great potential for distributed energy generation by installing PV panels on rooftops of residential and commercial buildings. Yet challenges arise along with the variability and non-dispatchability of the PV systems that affect the stability of the grid and the economics of the PV system. This paper investigates the integration of PV arrays for distributed generation applications by identifying a combination of buildings that will maximize solar energy output and minimize system variability. Particularly, we propose mean-variance optimization models to choose suitable rooftops for PV integration based on Markowitz mean-variance portfolio selection model. We further introduce quantity and cardinality constraints to result in a mixed integer quadratic programming problem. Case studies based on real data are presented. An efficient frontier is obtained for sample data that allows decision makers to choose a desired solar energy generation level with a comfortable variability tolerance level. Sensitivity analysis is conducted to show the tradeoffs between solar PV energy generation potential and variability.

Application of an electrochemical chlorine-generation system combined with solar energy as appropriate technology for water disinfection.

Science.gov (United States)

Choi, Jusol; Park, Chan Gyu; Yoon, Jeyong

2013-02-01

Affordable water disinfection is key to reducing the waterborne disease experienced worldwide where resources are limited. A simple electrochemical system that can generate chlorine as a disinfectant from the electrolysis of sodium chloride is an appropriate technology to produce clean water, particularly if driven by solar energy. This study examined the affordability of an electrochemical chlorine generation system using solar energy and developed the necessary design information for its implementation. A two-electrode batch reactor, equipped with commercial IrO(2)-coated electrodes and a solar panel (approximate area 0.2 m(2)), was used to produce chlorine from a 35g/L solution of NaCl. Within 1 h, sufficient chlorine (0.8 g) was generated to produce clean drinking water for about 80 people for 1 day (target microorganism: Escherichia coli; daily drinking water requirement: 2 L per person; chlorine demand: 4 mg/L; solar power: 650 W/m(2) in Seoul, Korea. Small household batteries were demonstrated to be a suitable alternative power source when there is insufficient solar irradiation. Using a 1 m(2) solar panel, the reactor would take only 15 min in Seoul, Korea, or 7 min in the tropics (solar power 1300 W/m(2)), to generate 1 g of chlorine. The solar-powered electrochemical chlorine generation system for which design information is provided here is a simple and affordable way to produce chlorine with which to convert contaminated water into clean drinking water.

Design and Performance of 20 Watts Portable Solar Generator

International Nuclear Information System (INIS)

Majid, Z A Abdul; Hazali, N; Hanafiah, M A K M; Abdullah, A A; Ismail, A F; Ruslan, M H; Sopian, K; Azmi, M S Mohd

2012-01-01

A new portable solar generator has been developed to generate electricity. It has the potential to replace petrol generator, widely used by peddlers at night markets (pasar malam). Conventional generators are heavy, oily, have high maintenance and use fossil fuel to generate electricity. The solar generator can generate 20 Watts of electricity. This amount of power can supply up to 96 hours of electricity for the purpose of lighting and running small electrical appliances. The power output is (alternating current) AC current using 150 Watts inverter with 200 Watts surge, suitable for all commercial single phase electric appliances. Solar charge controller is used to maximize the charging rate and to protect the battery. The system has low maintenance whereby the batteries need to be changed every three to four years, depending on the usage. The main concepts of portable solar generator are to reduce installation cost and to introduce a compact design of an optimal energy sizing system. The materials used to develop the solar generator can be easily obtained from local markets, thus reducing the cost of developing the system and making it suitable for commercialization.

Solar power generating device. Solar denryoku hassei sochi

Energy Technology Data Exchange (ETDEWEB)

Hayashi, E

1990-02-06

Concerning the existing solar power generating device using the analogue sequential partial shunt system, the number of interface line between the solar cell panel and the shunt dissipater is enormous and complicated in addition to the increased temperature rise of the shunt transistor in its working condition. Furthermore, concerning the digital sequential full shunt system, the above temperature rise becomes less, but the above number of interface line is likewise enormous. In order to remove the above defects, the solar power generating device which this invention concerns has the features that, in each row of solar cells connected to shunt transistors which are controlled respectively in a manner of on (saturation)/off independently in accordance with the amount of surplus electric power, the number of parallel connection of the unit cell circuits composing the each row above is made to be the different number respectively. Besides, it is proposed to have the feature in particular that such a number is made to be the number of 2 {sup n} (n is from zero to any integer, m) where n is increased by one progressively. 5 figs.

Fiscal 1976 Sunshine Project result report. Research on solar energy utilization systems (photovoltaic power generation); 1976 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

This report describes the fiscal 1976 research result on the technical and economical perspectives of various solar cells, high-efficiency solar cell and its evaluation technique, and a photovoltaic power generation system and its applications. On Si single-crystal slice solar cell, it was pointed out that cost reduction by automatic production process using no vacuum process is essential. On Si thin film solar cell, some problems to be solved for development of particle accelerating growth technique were pointed out. Study was also made on 2-6 group compound semiconductor solar cell, 3-5 group bulk crystal solar cell, 3-5 group thin film solar cell, solar collection solar cell, and raw polycrystal Si materials. On photovoltaic power generation systems, it was reconfirmed through reconsideration of power generation systems for every application that the photovoltaic power generation system for residences is promising. On medium- scale power generation systems, study was made on power load and system configuration in consideration of applications to electric railway, highway, and power source of isolated islands. (NEDO)

Simulation of the parabolic trough solar energy generation system with Organic Rankine Cycle

International Nuclear Information System (INIS)

He, Ya-Ling; Mei, Dan-Hua; Tao, Wen-Quan; Yang, Wei-Wei; Liu, Huai-Liang

2012-01-01

Highlights: ► A parabolic trough solar power generation system with ORC is numerically simulated. ► The effects of key parameters on collector field and system performance are studied. ► Collector heat loss increases with small absorber and glass tube interlayer pressure. ► Heat collecting efficiency increases with initial increase of absorber HTO flow rate. ► Recommended thermal storage system volumes are different in year four typical days. -- Abstract: A model for a typical parabolic trough solar thermal power generation system with Organic Rankine Cycle (PT-SEGS–ORC) was built within the transient energy simulation package TRNSYS, which is formed by integrating several submodels for the trough collector system, the single-tank thermal storage system, the auxiliary power system and the heat-electricity conversion system. With this model, the effects of several key parameters, including the interlayer pressure between the absorber tube and the glass tube (p inter ), the flow rate of high temperature oil in the absorber tube (v), solar radiation intensity (I dn ) and incidence angle (θ), on the performance of the parabolic trough collector field based on the meteorological data of Xi’an city were examined. The study shows that the heat loss of the solar collector (q loss ) increases sharply with the increase in p inter at beginning and then reaches to an approximately constant value. The variation of heat collecting efficiency (η hc ) with v is quite similar to the variation of q loss with p inter . However, I dn and θ exhibit opposite effect on η hc . In addition, it is found that the optimal volume of the thermal storage system is sensitively dependent on the solar radiation intensity. The optimal volumes are 100, 150, 50, and 0 m 3 for spring equinox, summer solstice, autumnal equinox and winter solstice, respectively.

FY 1977 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Solar thermal power generation systems); 1977 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyo netsu hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-03-31

This project is aimed at surveys and researches on operation, economic efficiency and performance evaluation of solar thermal power generation systems, and test methods, e.g., for aging the materials for their devices, in order to establish the methods for evaluating their performance. For operation of solar thermal power generation systems, a feasible system is a hybrid with another system, e.g., thermal power or nuclear system. For economic efficiency, heat-storage capacity will be based on power generation for around 4 hours a day for a solar system to be installed in Japan. The construction and light/heat-collecting costs should be reduced to around 300,000 yen/kW and 13,000 to 21,000 yen/m{sup 2}, respectively, in order to keep the power generation cost at around 23 yen/kWH. The energy analysis of solar thermal power generation, based on the data given by the industrial correlation tables, indicates that the total energy required for construction of the system can be recovered in 2 to 3 years. Also outlined are construction of a 1MW pilot plant and its facilities, and designs of the pilot plants with a curved surface or tower type light collector. A total of 12 types of reflection mirrors are screened for establishing the air-exposure testing methods. Methods for treating back surface edges of the reflection mirrors are also investigated. (NEDO)

75 FR 63198 - Notice of Availability of the Record of Decision for the Ivanpah Solar Electric Generating System...

Science.gov (United States)

2010-10-14

... Ivanpah Solar Electric Generating System (ISEGS) Project located in San Bernardino County, California. The... FX0000 LVRWB09B2400 LLCAD09000] Notice of Availability of the Record of Decision for the Ivanpah Solar Electric Generating System Project and Approved Plan Amendment to the California Desert Conservation Area...

On the optimal mix of wind and solar generation in the future Chinese power system

International Nuclear Information System (INIS)

Huber, Matthias; Weissbart, Christoph

2015-01-01

China is one of the largest and fastest growing economies in the world. Until now, the corresponding growth of electricity consumption has been mainly provided by coal. However, as national reserves are limited and since burning coal leads to severe environmental problems, the employment of alternative sources of energy supply has become an important part of the Chinese energy policy. Recent studies show that wind energy alone could meet all of China's electricity demand. While our results validate these findings with regard to annual production, we look at the hour-by-hour resolution and uncover a major limitation: wind generation will not match the demand at every given point in time. This results in significant periods with over- and undersupply. Our study shows that combining wind and solar generation in the power system reduces overproduction significantly and increases the capacity credit of the combined VRE (variable renewable energy sources). The article demonstrates that up to 70% of VRE comprising 20–30% solar generation in the form of photovoltaics (PV) can be integrated into China's electricity system with moderate storage requirements. We encourage planners to consider those findings in their long-term planning in order to set up a sustainable power system for China at low costs. - Highlights: • Analyzing the potentials for wind and solar generation in China. • Capacity credit of variable renewable energy sources. • Future storage demand for a renewable based Chinese power system. • Defining the optimal mix of wind and solar generation.

A PVTC system integrating photon-enhanced thermionic emission and methane reforming for efficient solar power generation

Institute of Scientific and Technical Information of China (English)

Wenjia Li; Hongsheng Wang; Yong Hao

2017-01-01

A new photovoltaic-thermochemical (PVTC) conceptual system integrating photon-enhanced thermionic emission (PETE) and methane steam reforming is proposed.Major novelty of the system lies in its potential adaptivity to primary fuels (e.g.methane) and high efficiencies of photovoltaic and thermochemical power generation,both of which result from its operation at much elevated temperatures (700-1000 ℃)compared with conventional photovoltaic-thermal (PVT) systems.Analysis shows that an overall power generation efficiency of 45.3％ and a net solar-to-electric efficiency of 39.1％ could be reached at an operating temperature of 750 ℃,after considering major losses during solar energy capture and conversion processes.The system is also featured by high solar share (37％) in the total power output,as well as high energy storage capability and very low CO2 emissions,both enabled by the integration of methane reforming with photovoltaic generation at high temperatures.

Performance evaluation of a stand-alone solar dish Stirling system for power generation suitable for off-grid rural electrification

International Nuclear Information System (INIS)

Kadri, Y.; Hadj Abdallah, H.

2016-01-01

Highlights: • Estimation of the output temperature reached by 2 m parabolic dish. • Output power estimation for uncontrollable load was done using Matlab®. • Validation of the proposed system under Tunisian conditions for rural electrification. - Abstract: The development of green power generation such as solar systems that have become a great interest for several countries especially for Tunisia as it presents a significant solar potential. For this purpose, this research has investigated the feasibility and the performance of standalone solar dish/Stirling micro generation plant for rural electrification. The considered hybrid system includes solar dish/Stirling engine, permanent magnet synchronous generator and a storage battery. To start with, thermal modeling and simulation have been carried out using Matlab® for the solar-driven Stirling heat engine system composed of an Alpha Stirling engine, a solar collector and a receiver, in which the radiation, convection, conduction and radiation heat loss have been taken into consideration for the selected design. For numerical validation of the receiver’s thermal model, simulation results were compared with experimental measurements reported for the EURODISH system with a reasonable degree of agreement. Second, the generated torque driving the generator has been estimated by the Adiabatic model of URIELI based on the classical fourth-order Runge-Kutta. In order for an autonomous control, the dish generator is connected to the load via power electronic converters where the bidirectional power flow is possible by the use of two voltage source converters in a back-to-back configuration. They are referred to as Stirling/generator side converter and load side inverter, both are oriented control by space vector pulse width modulation. In this context, the Stirling side converter is used to adjust the synchronous generator while the inverter controls the power flow between the direct current bus and the

FY 1977 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Photovoltaic power generation systems); 1977 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1978-03-31

This project is aimed at investigation on irradiation conditions of natural solar radiation to establish the performance evaluation methods; establishment of standard evaluation methods under natural solar radiation; and investigation on practical problems involved in the photovoltaic power generation systems. The research items are (1) photovoltaic power generation systems, and (2) standard evaluation methods for photovoltaic power generation systems installed on the ground. The item (1) includes the effect analysis in which existing Japanese residential buildings are selected to estimate possibility of installation of photovoltaic power generation systems and possible quantity of power generated; conceptual designs in which several systems conceivable at present are proposed and outlined, and a 30kW photovoltaic power generation system is taken up to investigate, e.g., solar cell arrays for the system, orthogonal conversion devices, associated facilities, conceptual designs of storage batteries, problems involved therein, and future research themes; and operation of the cell, which takes up operational examples of solar cell power sources, and operational problems viewed from the power transmission side. The item (2) proposes the standard evaluation methods (primary drafts) for the solar cell arrays and panels as those for photovoltaic power generation systems installed on the ground. (NEDO)

Fiscal 1976 Sunshine Project result report. Research on solar energy utilization systems (solar heat power generation); 1976 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyonetsu hatsuden

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

Research was made on solar heat power generation following last fiscal year, as a part of solar energy utilization technologies. In this fiscal year, in particular, research was made on the following: selection of suitable sites for solar heat power plants in Japan, estimation of expected power supply, positioning of a solar heat power system among future power systems, operation policy of solar heat power systems, survey on suitable sites for the 1,000kW pilot power plant, operation characteristics of the small test plant, design of the 1,000kW pilot power plant, test methods and facilities for every element equipment of solar heat power systems, an environmental test method for mostly solar collectors, and the profitability of solar heat power systems. Optimum operation temperature levels were nearly 350 degrees C for distributed systems and nearly 400 degrees C for centralized ones. The distributed system is profitable in a unit capacity range less than 5-10MWe, while the centralized system is profitable in a range over 10MWe. Under some assumptions, the power cost of solar heat power systems was estimated to be 20-30yen/kWH. (NEDO)

Solar photovoltaic systems and their use as grid-connected generators in the United Kingdom

Energy Technology Data Exchange (ETDEWEB)

Munro, D K; Hacker, R J; Thornycroft, J M [Halcrow Gilbert Associates Ltd., Swindon (United Kingdom)

1995-10-01

There is an increasing interest in the use of building-integrated solar photovoltaic generators as grid-connected generators. This paper discusses the experience with this technology in Europe. Typical systems and their integration into domestic and non-domestic buildings are described. Information is provided on the energy output that can be expected from the systems and the economics of their use. The paper provides an overview of the requirements for photovoltaic systems as grid-connected generation plant in the United Kingdom. (Author)

Solar Photovoltaic (PV) Distributed Generation Systems - Control and Protection

Science.gov (United States)

Yi, Zhehan

This dissertation proposes a comprehensive control, power management, and fault detection strategy for solar photovoltaic (PV) distribution generations. Battery storages are typically employed in PV systems to mitigate the power fluctuation caused by unstable solar irradiance. With AC and DC loads, a PV-battery system can be treated as a hybrid microgrid which contains both DC and AC power resources and buses. In this thesis, a control power and management system (CAPMS) for PV-battery hybrid microgrid is proposed, which provides 1) the DC and AC bus voltage and AC frequency regulating scheme and controllers designed to track set points; 2) a power flow management strategy in the hybrid microgrid to achieve system generation and demand balance in both grid-connected and islanded modes; 3) smooth transition control during grid reconnection by frequency and phase synchronization control between the main grid and microgrid. Due to the increasing demands for PV power, scales of PV systems are getting larger and fault detection in PV arrays becomes challenging. High-impedance faults, low-mismatch faults, and faults occurred in low irradiance conditions tend to be hidden due to low fault currents, particularly, when a PV maximum power point tracking (MPPT) algorithm is in-service. If remain undetected, these faults can considerably lower the output energy of solar systems, damage the panels, and potentially cause fire hazards. In this dissertation, fault detection challenges in PV arrays are analyzed in depth, considering the crossing relations among the characteristics of PV, interactions with MPPT algorithms, and the nature of solar irradiance. Two fault detection schemes are then designed as attempts to address these technical issues, which detect faults inside PV arrays accurately even under challenging circumstances, e.g., faults in low irradiance conditions or high-impedance faults. Taking advantage of multi-resolution signal decomposition (MSD), a powerful signal

A self-sustaining high-strength wastewater treatment system using solar-bio-hybrid power generation.

Science.gov (United States)

Bustamante, Mauricio; Liao, Wei

2017-06-01

This study focuses on system analysis of a self-sustaining high-strength wastewater treatment concept combining solar technologies, anaerobic digestion, and aerobic treatment to reclaim water. A solar bio-hybrid power generation unit was adopted to power the wastewater treatment. Concentrated solar power (CSP) and photovoltaics (PV) were combined with biogas energy from anaerobic digestion. Biogas is also used to store the extra energy generated by the hybrid power unit and ensure stable and continuous wastewater treatment. It was determined from the energy balance analysis that the PV-bio hybrid power unit is the preferred energy unit to realize the self-sustaining high-strength wastewater treatment. With short-term solar energy storage, the PV-bio-hybrid power unit in Phoenix, AZ requires solar collection area (4032m 2 ) and biogas storage (35m 3 ), while the same unit in Lansing, MI needs bigger solar collection area and biogas storage (5821m 2 and 105m 3 , respectively) due to the cold climate. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effect of working fluids on the performance of a novel direct vapor generation solar organic Rankine cycle system

International Nuclear Information System (INIS)

Li, Jing; Alvi, Jahan Zeb; Pei, Gang; Ji, Jie; Li, Pengcheng; Fu, Huide

2016-01-01

Highlights: • A novel, flexible direct vapor generation solar ORC is proposed. • Technical feasibility of the system is discussed. • Fluid effect on collector efficiency is explored. • The system is more efficient than solar ORC with HTF. - Abstract: A novel solar organic Rankine cycle (ORC) system with direct vapor generation (DVG) is proposed. A heat storage unit is embedded in the ORC to guarantee the stability of power generation. Compared with conventional solar ORCs, the proposed system avoids the secondary heat transfer intermediate and shows good reaction to the fluctuation of solar radiation. The technical feasibility of the system is discussed. Performance is analyzed by using 17 dry and isentropic working fluids. Fluid effects on the efficiencies of ORC, collectors and the whole system are studied. The results indicate that the collector efficiency generally decreases while the ORC and system efficiencies increase with the increment in fluid critical temperature. At evaporation temperature of 120 °C and solar radiation of 800 Wm −2 , the ORC, collector and overall thermal efficiencies of R236fa are 10.59, 56.14 and 5.08% while their values for Benzene are 12.5, 52.58 and 6.57% respectively. The difference between collector efficiencies using R236fa and Benzene gets larger at lower solar radiation. The heat collection is strongly correlated with latent and sensible heat of the working fluid. Among the fluids, R123 exhibits the highest overall performance and seems to be suitable for the proposed system in the short term.

Multi-Generation Concentrating Solar-Hydrogen Power System for Sustainable Rural Development

Energy Technology Data Exchange (ETDEWEB)

Krothapalli, A.; Greska, B.

2007-07-01

This paper describes an energy system that is designed to meet the demands of rural populations that currently have no access to grid-connected electricity. Besides electricity, it is well recognized that rural populations need at least a centralized refrigeration system for storage of medicines and other emergency supplies, as well as safe drinking water. Here we propose a district system that will employ a multi-generation concentrated solar power (CSP) system that will generate electricity and supply the heat needed for both absorption refrigeration and membrane distillation (MD) water purification. The electricity will be used to generate hydrogen through highly efficient water electrolysis and individual households can use the hydrogen for generating electricity, via affordable proton exchange membrane (PEM) fuel cells, and as a fuel for cooking. The multi-generation system is being developed such that its components will be easy to manufacture and maintain. As a result, these components will be less efficient than their typical counterparts but their low cost-to-efficiency ratio will allow for us to meet our installation cost goal of $1/Watt for the entire system. The objective of this paper is to introduce the system concept and discuss the system components that are currently under development. (auth)

Solar fuels generator

Science.gov (United States)

Lewis, Nathan S.; Spurgeon, Joshua M.

2016-10-25

The solar fuels generator includes an ionically conductive separator between a gaseous first phase and a second phase. A photoanode uses one or more components of the first phase to generate cations during operation of the solar fuels generator. A cation conduit is positioned provides a pathway along which the cations travel from the photoanode to the separator. The separator conducts the cations. A second solid cation conduit conducts the cations from the separator to a photocathode.

Modeling and simulations of a 30 MWe solar electric generating system using parabolic trough collectors in Turkey

Energy Technology Data Exchange (ETDEWEB)

Usta, Yasemin [Anyl Asansor Ltd (Turkey)], email: syusta@gmail.com; Baker, Derek [Middle East Technical University (Turkey)], email: dbaker@metu.edu.tr; Kaftanoglu, Bilgin [Atilim University (Turkey)], email: bilgink@atilim.edu.tr

2011-07-01

With the energy crisis and the increasing concerns about climate change, the interest in concentrating solar power (CSP) systems is growing in Turkey. The aim of this paper is to develop a model of a CSP system using a field of parabolic trough collectors and to assess the predicted performance of the system. A model was developed for a 30MWe solar generating system in Antalya, Turkey, using TRNSYS software, the solar thermal electric components library and information on an existing system in Kramer Junction, California, United States. Annual simulations were then performed for both systems in Antalya and California using weather data. It was found that the predictions were in good agreement with published data. In addition results showed that Antalya's system would generate 30% less than Kramer Junction's system on an annual basis. This paper provides useful information on modeling and simulation of CSP systems.

FY 1978 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Photovoltaic power generation systems); 1978 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1979-03-01

This survey report provides the basic data for planning national projects to smoothly raise the large industry of solar cell industry in the future by studying how to promote the research and development projects for this area, continuously pursued from the establishment of the Sunshine Project. This report clarifies, first of all, the concept of long-term schedules for research and development of solar thermal power generation systems, based on which technical themes are concretely surveyed, and their economic viability and ripple effects on the other industries are analyzed. The industry of solar thermal power generation systems is a new industry, even based on the global horizons, backed up by the Japan's high-technological areas of electronics and semiconductor industries. It is one of important projects to be urgently developed, also viewed from the above standpoint. This report describes the long-term visions of solar thermal power generation systems, and the research and development projects therefor; stock materials for solar cells and problems involved therein; research and development projects for low-cost solar cells; photovoltaic power generation systems, and the research and development projects therefor; conceptual designs of photovoltaic power generation systems; and standard analytical procedures for solar cells, and technical problems involved therein. (NEDO)

FY 1978 Annual report on Sunshine Project results. Survey and research on systems utilizing solar energy (Photovoltaic power generation systems); 1978 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyoko hatsuden system

Energy Technology Data Exchange (ETDEWEB)

NONE

1979-03-01

This survey report provides the basic data for planning national projects to smoothly raise the large industry of solar cell industry in the future by studying how to promote the research and development projects for this area, continuously pursued from the establishment of the Sunshine Project. This report clarifies, first of all, the concept of long-term schedules for research and development of solar thermal power generation systems, based on which technical themes are concretely surveyed, and their economic viability and ripple effects on the other industries are analyzed. The industry of solar thermal power generation systems is a new industry, even based on the global horizons, backed up by the Japan's high-technological areas of electronics and semiconductor industries. It is one of important projects to be urgently developed, also viewed from the above standpoint. This report describes the long-term visions of solar thermal power generation systems, and the research and development projects therefor; stock materials for solar cells and problems involved therein; research and development projects for low-cost solar cells; photovoltaic power generation systems, and the research and development projects therefor; conceptual designs of photovoltaic power generation systems; and standard analytical procedures for solar cells, and technical problems involved therein. (NEDO)

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)

Snow melting system with electric heating using photovoltaic power generation; Solar yusetsuko

Energy Technology Data Exchange (ETDEWEB)

Sasaki, M; Fujita, S; Kaga, T; Koyama, N [Hachinohe Institute of Technology, Aomori (Japan)

1996-10-27

This paper clarifies the solar characteristics in Hachinohe district, to investigate a possibility of the snow melting system with electric heating using solar energy. Power demand for snow melting, power generated by the photovoltaic (PV) array, area of PV array, and working conditions of the system, as to temperature, precipitation and snowfall, were investigated. The percentage of sunshine is 44% in Hachinohe district, which has more fortunate natural condition for utilizing solar radiation compared with that of 20% in Aomori prefecture. The intensity of solar radiation in winter from December to March is around 500 W/m{sup 2} in average, which is equivalent to the quantity of solar radiation, around 2 kWh/m{sup 2} a day. When assuming that snow on the road surface is frozen at the snowfall under the air temperature below -3{degree}C, the occurrence frequency is 50% during January and February in Hachinohe district, which means one frozen day for two days and is equivalent to the occurrence frequency of frozen days, 34% in average during winter. The electric application ratio is 0.34 at the maximum in winter. That is, days of 34% for one month are required for snow melting. 3 figs., 3 tabs.

A study on evaluating the power generation of solar-wind hybrid systems in Izmir, Turkey

Energy Technology Data Exchange (ETDEWEB)

Ulgen, K. [Ege Univ., Solar Energy Inst., Izmir (Turkey); Hepbasli, A. [Ege Univ., Dept. of Mechanical Engineering, Izmir (Turkey)

2003-03-15

Turkey is abundant in terms of renewable energy resources. Residential and industrial utilization of solar energy started in the 1980s, while the first Build-Operate-Transfer (BOT) windmill park, located at Alacati, Izmir, was commissioned in 1998. Additionally, power generation through solar-wind hybrid systems has recently appeared on the Turkish market. This study investigates the wind and solar thermal power availability in Izmir, located in the western part of Turkey. Simple models were developed to determine wind, solar, and hybrid power resources per unit area. Experimental data, consisting of hourly records over a 5 yr period, 1995-1999, were measured in the Solar/Wind Meteorological Station of the Solar Energy Institute at Ege University. Correlations between solar and wind power data were carried out on an hourly, a daily, and a monthly basis. It can be concluded that possible applications of hybrid systems could be considered for the efficient utilization of these resources. (Author)

Solar Energy Systems for Lunar Oxygen Generation

Science.gov (United States)

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

2010-01-01

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

Solar energy for steam generation in Brazil

Energy Technology Data Exchange (ETDEWEB)

De Carvalho, Jr, A V; Orlando, A DeF; Magnoli, D

1979-05-01

Steam generation is a solar energy application that has not been frequently studied in Brazil, even though for example, about 10% of the national primary energy demand is utilized for processing heat generation in the range of 100 to 125/sup 0/C. On the other hand, substitution of automotive gasoline by ethanol, for instance, has received much greater attention even though primary energy demand for process heat generation in the range of 100 to 125/sup 0/C is of the same order of magnitude than for total automotive gasoline production. Generation of low-temperature steam is analyzed in this article using distributed systems of solar collectors. Main results of daily performance simulation of single flat-plate collectors and concentrating collectors are presented for 20/sup 0/S latitude, equinox, in clear days. Flat plate collectors considered are of the aluminum roll-bond absorber type, selective surface single or double glazing. Considering feedwater at 20/sup 0/C, saturated steam at 120/sup 0/C and an annual solar utilization factor of 50%, a total collector area of about 3,000 m/sup 2/ is necessary for the 10 ton/day plant, without energy storage. A fuel-oil back-up system is employed to complement the solar steam production, when necessary. Preliminary economic evaluation indicates that, although the case-study shows today a long payback period relative to subsidized fuel oil in the domestic market (over 20 years in the city of Rio de Janeiro), solar steam systems may be feasible in the medium term due to projected increase of fuel oil price in Brazil.

Thermo-economic analysis of an integrated solar power generation system using nanofluids

International Nuclear Information System (INIS)

Alashkar, Adnan; Gadalla, Mohamed

2017-01-01

Highlights: • Develop a thermo-economic analysis of an integrated solar-power generation system. • A thermodynamic optimization is proposed to maximize system performance. • Select the optimum nanofluid to replace conventional heating fluids inside a PTSC. • Study the effect of thermal energy storage on performance and cost of the system. • Perform monthly and daily analyses to analyze system behavior using nanofluids. - Abstract: In this paper, a thermo-economic analysis of an Integrated Solar Regenerative Rankine Cycle (ISRRC) is performed. The ISRRC consists of a nanofluid-based Parabolic Trough Solar Collector (PTSC), and a Thermal Energy Storage System (TES) integrated with a Regenerative Rankine Cycle. The effect of dispersing metallic and non-metallic nanoparticles into conventional heating fluids on the output performance and cost of the ISRRC is studied for different volume fractions and for three modes of operation. The first mode assumes no storage, while the second and the third assume a storage system with a storage period of 7.5 h and 10 h respectively. For the modes of operation with the TES, the charging and discharging cycles are explained. The results show that the presence of the nanoparticles leads to an increase in the overall energy produced by the ISRRC for all modes of operation, causing a decrease in the Levelized Cost of Electricity (LEC), and an increase in the net savings of the ISRRC. After comparing the three modes of operation, it is established that the existence of a storage system leads to a higher power generation, and a lower LEC; however, the efficiency of the cycle drops. It is seen that the maximum increase in the annual energy output of the ISRRC caused by the addition of Cu nanoparticles to Syltherm 800 is approximately 3.1%, while the maximum increase in the net savings is about 2.4%.

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.

Energy and exergy analyses on a novel hybrid solar heating, cooling and power generation system for remote areas

International Nuclear Information System (INIS)

Zhai, H.; Dai, Y.J.; Wu, J.Y.; Wang, R.Z.

2009-01-01

In this study, a small scale hybrid solar heating, chilling and power generation system, including parabolic trough solar collector with cavity receiver, a helical screw expander and silica gel-water adsorption chiller, etc., was proposed and extensively investigated. The system has the merits of effecting the power generation cycle at lower temperature level with solar energy more efficiently and can provide both thermal energy and power for remote off-grid regions. A case study was carried out to evaluate an annual energy and exergy efficiency of the system under the climate of northwestern region of China. It is found that both the main energy and exergy loss take place at the parabolic trough collector, amount to 36.2% and 70.4%, respectively. Also found is that the studied system can have a higher solar energy conversion efficiency than the conventional solar thermal power generation system alone. The energy efficiency can be increased to 58.0% from 10.2%, and the exergy efficiency can be increased to 15.2% from 12.5%. Moreover, the economical analysis in terms of cost and payback period (PP) has been carried out. The study reveals that the proposed system the PP of the proposed system is about 18 years under present energy price conditions. The sensitivity analysis shows that if the interest rate decreases to 3% or energy price increase by 50%, PP will be less than 10 years. (author)

Automatic generation and analysis of solar cell IV curves

Science.gov (United States)

Kraft, Steven M.; Jones, Jason C.

2014-06-03

A photovoltaic system includes multiple strings of solar panels and a device presenting a DC load to the strings of solar panels. Output currents of the strings of solar panels may be sensed and provided to a computer that generates current-voltage (IV) curves of the strings of solar panels. Output voltages of the string of solar panels may be sensed at the string or at the device presenting the DC load. The DC load may be varied. Output currents of the strings of solar panels responsive to the variation of the DC load are sensed to generate IV curves of the strings of solar panels. IV curves may be compared and analyzed to evaluate performance of and detect problems with a string of solar panels.

Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

Science.gov (United States)

Azoumah, Y.; Yamegueu, D.; Py, X.

2012-02-01

Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original "flexy energy" concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

Sustainable electricity generation by solar pv/diesel hybrid system without storage for off grids areas

International Nuclear Information System (INIS)

Azoumah, Y; Yamegueu, D; Py, X

2012-01-01

Access to energy is known as a key issue for poverty reduction. The electrification rate of sub Saharan countries is one of the lowest among the developing countries. However this part of the world has natural energy resources that could help raising its access to energy, then its economic development. An original 'flexy energy' concept of hybrid solar pv/diesel/biofuel power plant, without battery storage, is developed in order to not only make access to energy possible for rural and peri-urban populations in Africa (by reducing the electricity generation cost) but also to make the electricity production sustainable in these areas. Some experimental results conducted on this concept prototype show that the sizing of a pv/diesel hybrid system by taking into account the solar radiation and the load/demand profile of a typical area may lead the diesel generator to operate near its optimal point (70-90 % of its nominal power). Results also show that for a reliability of a PV/diesel hybrid system, the rated power of the diesel generator should be equal to the peak load. By the way, it has been verified through this study that the functioning of a pv/Diesel hybrid system is efficient for higher load and higher solar radiation.

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

MEMS Solar Generators

OpenAIRE

Grbovic, Dragoslav; Osswald, Sebastian

2011-01-01

Approved for public release; distribution is unlimited Using MEMS bimaterial structures to build highly efficient solar energy generators. This is a novel approach that utilizes developments in the area of bimaterial sensors and applies them in the field of solar energy harvesting.

Power generation enhancement in a salinity-gradient solar pond power plant using thermoelectric generator

International Nuclear Information System (INIS)

Ziapour, Behrooz M.; Saadat, Mohammad; Palideh, Vahid; Afzal, Sadegh

2017-01-01

Highlights: • Thermoelectric generator was used and simulated within a salinity-gradient solar pond power plant. • Results showed that the thermoelectric generator can be able to enhance the power plant efficiency. • Results showed that the presented models can be able to produce generation even in the cold months. • The optimum size of area of solar pond based on its effect on efficiency is 50,000 m 2 . - Abstract: Salinity-gradient solar pond (SGSP) has been a reliable supply of heat source for power generation when it has been integrated with low temperature thermodynamics cycles like organic Rankine cycle (ORC). Also, thermoelectric generator (TEG) plays a critical role in the production of electricity from renewable energy sources. This paper investigates the potential of thermoelectric generator as a power generation system using heat from SGSP. In this work, thermoelectric generator was used instead of condenser of ORC with the purpose of improving the performance of system. Two new models of SGSP have been presented as: (1) SGSP using TEG in condenser of ORC without heat exchanger and (2) SGSP using TEG in condenser of ORC with heat exchanger. These proposed systems was evaluated through computer simulations. The ambient conditions were collected from beach of Urmia lake in IRAN. Simulation results indicated that, for identical conditions, the model 1 has higher performance than other model 2. For models 1 and 2 in T LCZ = 90 °C, the overall thermal efficiency of the solar pond power plant, were obtained 0.21% and 0.2% more than ORC without TEG, respectively.

Fiscal 1974 Sunshine Project result report. Research on solar energy utilization systems (solar heat power generation); 1974 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Taiyonetsu hatsuden

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-03-01

This report summarizes the fiscal 1974 research result on solar heat power generation. The following are promising as solar heat power plant sites in Japan: Large-scale sites such as the foot of volcanos, riverbed, railway site and road, medium-scale sites such as isolated island, saltpan site and industrial park, and small-scale sites such as factory site, factory roof floor, housing complex, warehouse and school. Based on the primary concept design of both curved reflector type and tower type 1,000kW class solar heat power plants, various requirements were clarified roughly. It was clarified that food, fiber and non-ferrous metal factories can cover 80-90% of their thermal energy requirements with high- temperature solar heat, while factories related to food and fiber can cover even nearly 100% of their electric power requirements with solar heat. Study was also made on specifications of a solar simulator as common use facility necessary for characteristic evaluation of equipment and materials for solar heat power generation systems. (NEDO)

Realistic generation cost of solar photovoltaic electricity

International Nuclear Information System (INIS)

Singh, Parm Pal; Singh, Sukhmeet

2010-01-01

Solar photovoltaic (SPV) power plants have long working life with zero fuel cost and negligible maintenance cost but requires huge initial investment. The generation cost of the solar electricity is mainly the cost of financing the initial investment. Therefore, the generation cost of solar electricity in different years depends on the method of returning the loan. Currently levelized cost based on equated payment loan is being used. The static levelized generation cost of solar electricity is compared with the current value of variable generation cost of grid electricity. This improper cost comparison is inhibiting the growth of SPV electricity by creating wrong perception that solar electricity is very expensive. In this paper a new method of loan repayment has been developed resulting in generation cost of SPV electricity that increases with time like that of grid electricity. A generalized capital recovery factor has been developed for graduated payment loan in which capital and interest payment in each installment are calculated by treating each loan installment as an independent loan for the relevant years. Generalized results have been calculated which can be used to determine the cost of SPV electricity for a given system at different places. Results show that for SPV system with specific initial investment of 5.00 cents /kWh/year, loan period of 30 years and loan interest rate of 4% the levelized generation cost of SPV electricity with equated payment loan turns out to be 28.92 cents /kWh, while the corresponding generation cost with graduated payment loan with escalation in annual installment of 8% varies from 9.51 cents /kWh in base year to 88.63 cents /kWh in 30th year. So, in this case, the realistic current generation cost of SPV electricity is 9.51 cents /kWh and not 28.92 cents /kWh. Further, with graduated payment loan, extension in loan period results in sharp decline in cost of SPV electricity in base year. Hence, a policy change is required

Experimental Investigation on the Feasibility of Using a Fresnel Lens as a Solar-Energy Collection System for Enhancing On-Orbit Power Generation Performance

Directory of Open Access Journals (Sweden)

Tae-Yong Park

2017-01-01

Full Text Available Cube satellites have a limitation for generating power because of their cubic structure and extremely small size. In addition, the incidence angle between the sun and the solar panels continuously varies owing to the revolution and rotation of the satellite according to the attitude control strategy. This angle is an important parameter for determining the power generation performance of the cube satellite. In this study, we performed an experimental feasibility study that uses a Fresnel lens as a solar-energy collection system for cube satellite applications, so that the power generation efficiency can be enhanced under the worst incidence angle condition between the sun and solar panels by concentrating and redirecting solar energy onto the solar panels with a commercial Fresnel lens. To verify the effectiveness of the proposed system, we conducted a power-measurement test using a solar simulator and Fresnel lenses at various angles to the light source. In addition, we predicted the on-orbit power-generation enhancement achieved by employing the solar-energy collection system with various attitude control strategies.

Low-cost distributed solar-thermal-electric power generation

Science.gov (United States)

Der Minassians, Artin; Aschenbach, Konrad H.; Sanders, Seth R.

2004-01-01

Due to their high relative cost, solar electric energy systems have yet to be exploited on a widespread basis. It is believed in the energy community that a technology similar to photovoltaic (PV), but offered at about $1/W would lead to widespread deployment at residential and commercial sites. This paper addresses the investigation and feasibility study of a low-cost solar thermal electricity generation technology, suitable for distributed deployment. Specifically, we discuss a system based on nonimaging solar concentrators, integrated with free-piston Stirling engine devices incorporating integrated electric generation. We target concentrator-collector operation at moderate temperatures, in the range of 125°C to 150°C. This temperature is consistent with use of optical concentrators with concentration ratios on the order of 1-2. These low ratio concentrators admit wide angles of radiation acceptance and are thus compatible with no diurnal tracking, and no or only a few seasonal adjustments. Thus, costs and reliability hazards associated with tracking hardware systems are avoided. Further, we note that in the intended application, there is no shortage of incident solar energy, but rather it is the capital cost of the solar-electric system that is most precious. Thus, we outline a strategy for exploiting solar resources in a cost constrained manner. The paper outlines design issues, and a specific design for an appropriately dimensioned free-piston Stirling engine. Only standard low-cost materials and manufacturing methods are required to realize such a machine.

Modeling, design and analysis of a stand-alone hybrid power generation system using solar/urine

International Nuclear Information System (INIS)

Wu, Wei; Zhou, Ya-Yan; Lin, Mu-Hsuan; Hwang, Jenn-Jiang

2013-01-01

Highlights: • The stand-alone hybrid power system is presented. • The urine-to-hydrogen processor is proposed. • Scenario analysis of the hybrid power dispatching and the urine/solar demands is investigated. • The design, modeling and optimization of the hybrid power system is addressed by Aspen Plus and Matlab. - Abstract: The urine turned to hydrogen as an energy conversion process is integrated into a stand-alone hybrid (PV/FC/battery) power generation system. The optimization and simulation of a new urine-to-hydrogen processor is evaluated in Aspen Plus environment. In our approach, the PV generator aims to reduce urine consumption and the lithium-ion battery can compensate the power gap due to the fuel processing delay. Based on prescribed patterns of solar irradiation and the daily load demand of a 30-persons classroom, scenario analyses of the hybrid power dispatching and operational feasibility is addressed

Design and analysis of solar thermoelectric power generation system

Science.gov (United States)

Vatcharasathien, Narong; Hirunlabh, Jongjit; Khedari, Joseph; Daguenet, Michel

2005-09-01

This article reports on the design and performance analysis of a solar thermoelectric power generation plant (STEPG). The system considers both truncated compound parabolic collectors (CPCs) with a flat receiver and conventional flat-plate collectors, thermoelectric (TE) cooling and power generator modules and appropriate connecting pipes and control devices. The design tool uses TRNSYS IIsibat-15 program with a new component we developed for the TE modules. The main input data of the system are the specifications of TE module, the maximum hot side temperature of TE modules, and the desired power output. Examples of the design using truncated CPC and flat-plate collectors are reported and discussed for various slope angle and half-acceptance angle of CPC. To minimize system cost, seasonal adjustment of the slope angle between 0° and 30° was considered, which could give relatively high power output under Bangkok ambient condition. Two small-scale STEPGs were built. One of them uses electrical heater, whereas the other used a CPC with locally made aluminum foil reflector. Measured data showed reasonable agreement with the model outputs. TE cooling modules were found to be more appropriate. Therefore, the TRNSYS software and the developed TE component offer an extremely powerful tool for the design and performance analysis of STEPG plant.

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...

Next generation solar energy. From fundamentals to applications

Energy Technology Data Exchange (ETDEWEB)

NONE

2011-07-01

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

Solar Fuel Generator

Science.gov (United States)

Lewis, Nathan S. (Inventor); West, William C. (Inventor)

2017-01-01

The disclosure provides conductive membranes for water splitting and solar fuel generation. The membranes comprise an embedded semiconductive/photoactive material and an oxygen or hydrogen evolution catalyst. Also provided are chassis and cassettes containing the membranes for use in fuel generation.

Expanding photovoltaic penetration with residential distributed generation from hybrid solar photovoltaic and combined heat and power systems

International Nuclear Information System (INIS)

Pearce, J.M.

2009-01-01

The recent development of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. This paper investigates the potential of deploying a distributed network of PV + CHP hybrid systems in order to increase the PV penetration level in the U.S. The temporal distribution of solar flux, electrical and heating requirements for representative U.S. single family residences were analyzed and the results clearly show that hybridizing CHP with PV can enable additional PV deployment above what is possible with a conventional centralized electric generation system. The technical evolution of such PV + CHP hybrid systems was developed from the present (near market) technology through four generations, which enable high utilization rates of both PV-generated electricity and CHP-generated heat. A method to determine the maximum percent of PV-generated electricity on the grid without energy storage was derived and applied to an example area. The results show that a PV + CHP hybrid system not only has the potential to radically reduce energy waste in the status quo electrical and heating systems, but it also enables the share of solar PV to be expanded by about a factor of five. (author)

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

Evaluation small scale, grid connected wind and solar distributed generation systems in Jordan

International Nuclear Information System (INIS)

Naji, G. J.; Tahboub, K. K.; Jalham, I. S.

2011-01-01

In this paper, the potential of utilizing wind and solar Private Distributed Generation (PDG) for utility interactive systems is investigated for 11 selected stations (sites) in Jordan. Six customer categories are considered: residential, office, commercial mall, school, hospital and hotel. The main goal of this study was to evaluate the potential of utilizing different grid connected PDG under different conditions such as their location, size, served building category, number of people who share and own the equipment and system type whether wind, solar or hybrid based. It was found that solar systems are still not attractive for all location due to their associated high cost, while wind systems would vary widely depending on the customer category, location and the size of the equipment. Based on the Benefit to Cost ratio criterion, the most attractive sites for installing wind PDGS for residential communities are Ras Muneef, Mafraq, Aqaba, Irbid and H5, while it doesn't seem attractive at Amman,Shoubak, Ghor Essafi, Deir Alla, Maan and H4. On the other hand, the wind on-grid PDGS is very attractive at Ras Muneef, mafraq and Aqaba for commercial buildings, less attractive at H5 and irbid, while it's not attractive at the other sites. The attraction for hybrid PDG systems is closer to those of wind systems alone. (authors).

On the exergetic capacity factor of a wind – Solar power generation system

DEFF Research Database (Denmark)

Xydis, George

2013-01-01

production. In this paper, a detailed exergetic analysis aiming to identify the overall Exergetic Capacity Factor (ExCF) for a wind – solar power generation system was done. ExCF, as a new parameter, can be used for better classification and evaluation of renewable energy sources (RES). All the energy...... and exergy characteristics of wind and solar energy were examined in order to identify the variables that affect the power output of the hybrid system. A validated open source PV optimization tool was also included in the analysis, It was shown that parameters as e.g. air density or tracking losses, low......In the recent years, exergy analysis has become a very important tool in the evaluation of systems’ efficiency. It aims on minimizing the energy related-system losses and therefore maximizing energy savings and helps society substantially to move towards sustainable development and cleaner...

Application of solar panels in vehicle parking under the concept of distributed generation

International Nuclear Information System (INIS)

Calderon Vega, Jefferson

2013-01-01

An analysis of solar panels technologies is realized to implement an application of distributed generation in vehicle parking. The different technologies available in the market about solar panels are investigated. The climatological and geographical conditions are studied for the use of solar energy. The electrical requirements are determined for the implementation of solar panels as a distributed generation system. The benefit/cost is analyzed in establishments of vehicle parking for the implementation of solar panels. A photovoltaic system was developed in a vehicle parking attached at the Colegio Federado de Ingenieros y Arquitectos, and also the technical feasibility has been determined. The photovoltaic systems about roofs of buildings every day have been more viable, due that the cost of the systems has been lower and more efficient. Crystalline silicon ''mono'' or ''poly'' has been the most reliable option in the development of new technologies in solar cells. Costa Rica is found in a zone where the photovoltaic solar energy is harnessed and should to be fostered by the engineering sector. The installation of photovoltaic systems has contributed to reduce the carbon footprint in the distributed generation [es

A hybrid solar and chemical looping combustion system for solar thermal energy storage

International Nuclear Information System (INIS)

Jafarian, Mehdi; Arjomandi, Maziar; Nathan, Graham J.

2013-01-01

Highlights: ► A novel solar–CLC hybrid system is proposed which integrates a CLC with solar thermal energy. ► The oxygen carrier particles are used as storage medium for thermal energy storage. ► A solar cavity reactor is proposed for fuel reactor. ► The absorbed solar energy is stored in the particles to produce a base heat load. -- Abstract: A novel hybrid of a solar thermal energy and a chemical looping combustion (CLC) system is proposed here, which employs the oxygen carrier particles in a CLC system to provide diurnal thermal energy storage for concentrated solar thermal energy. In taking advantage of the chemical and sensible energy storage systems that are an inherent part of a CLC system, this hybrid offers potential to achieve cost effective, base load power generation for solar energy. In the proposed system, three reservoirs have been added to a conventional CLC system to allow storage of the oxygen carrier particles, while a cavity solar receiver has been chosen for the fuel reactor. The performance of the system is evaluated using ASPEN PLUS software, with the model being validated using independent simulation result reported previously. Operating temperature, solar efficiency, solar fraction, exergy efficiency and the fraction of the solar thermal energy stored for a based load power generation application are reported.

Economic aspects of grid connected solar electricity generation

International Nuclear Information System (INIS)

Pharabod, F.

1993-01-01

Experience gained with available solar thermal technologies enlighten on options for research and development on solar electricity generation. The proposed analysis of new solar technologies concerns market, costs and profit viewpoint: - Systems under development have to fit with consumers' needs and utilities' specifications, technology is not the only item to study. - Expense headings depend on technological options and operation procedures such as size of the plant, solar only or hybrid concept. - Anticipation of revenues highly depends on direct insolation quality and on local conditions for introducing the electric power generated into the network: daily direct insolation measurements and annual local load curve are prerequisite data. Strategic advantages regarding environment and sustainable development are to be pointed out, specially in industrialized countries or for projects including financing institutions. As far as generating electric power on the grid is a major challenge in the development of a number of countries in the sun belt, cooperation between industrialized and developing countries, under the auspices of international organization, has to be promoted. (Author) 12 refs

Efficiency Evaluation of a Photovoltaic System Simultaneously Generating Solar Electricity and Hydrogen for Energy Storage

Directory of Open Access Journals (Sweden)

Abermann S.

2012-10-01

Full Text Available The direct combination of a photovoltaic system with an energy storage component appears desirable since it produces and stores electrical energy simultaneously, enabling it to compensate power generation fluctuations and supply sufficient energy during low- or non-irradiation periods. A novel concept based on hydrogenated amorphous silicon (a-Si:H triple-junction solar cells, as for example a-Si:H/a-SiGe:H/a-SiGe:H, and a solar water splitting system integrating a polymer electrolyte membrane (PEM electrolyser is presented. The thin film layer-by-layer concept allows large-area module fabrication applicable to buildings, and exhibits strong cost-reduction potential as compared to similar concepts. The evaluation shows that it is possible to achieve a sufficient voltage of greater than 1.5 V for effective water splitting with the a-Si based solar cell. Nevertheless, in the case of grid-connection, the actual energy production cost for hydrogen storage by the proposed system is currently too high.

Solar electric power generation photovoltaic energy systems

CERN Document Server

Krauter, Stefan CW

2007-01-01

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

Probabilistic generation assessment system of renewable energy in Korea

Directory of Open Access Journals (Sweden)

Yeonchan Lee

2016-01-01

Full Text Available This paper proposes probabilistic generation assessment system introduction of renewable energy generators. This paper is focused on wind turbine generator and solar cell generator. The proposed method uses an assessment model based on probabilistic model considering uncertainty of resources (wind speed and solar radiation. Equivalent generation function of the wind and solar farms are evaluated. The equivalent generation curves of wind farms and solar farms are assessed using regression analysis method using typical least square method from last actual generation data for wind farms. The proposed model is applied to Korea Renewable Generation System of 8 grouped 41 wind farms and 9 grouped around 600 solar farms in South Korea.

Solar system fault detection

Science.gov (United States)

Farrington, R.B.; Pruett, J.C. Jr.

1984-05-14

A fault detecting apparatus and method are provided for use with an active solar system. The apparatus provides an indication as to whether one or more predetermined faults have occurred in the solar system. The apparatus includes a plurality of sensors, each sensor being used in determining whether a predetermined condition is present. The outputs of the sensors are combined in a pre-established manner in accordance with the kind of predetermined faults to be detected. Indicators communicate with the outputs generated by combining the sensor outputs to give the user of the solar system and the apparatus an indication as to whether a predetermined fault has occurred. Upon detection and indication of any predetermined fault, the user can take appropriate corrective action so that the overall reliability and efficiency of the active solar system are increased.

Validation, Optimization and Simulation of a Solar Thermoelectric Generator Model

Science.gov (United States)

Madkhali, Hadi Ali; Hamil, Ali; Lee, HoSung

2017-12-01

This study explores thermoelectrics as a viable option for small-scale solar thermal applications. Thermoelectric technology is based on the Seebeck effect, which states that a voltage is induced when a temperature gradient is applied to the junctions of two differing materials. This research proposes to analyze, validate, simulate, and optimize a prototype solar thermoelectric generator (STEG) model in order to increase efficiency. The intent is to further develop STEGs as a viable and productive energy source that limits pollution and reduces the cost of energy production. An empirical study (Kraemer et al. in Nat Mater 10:532, 2011) on the solar thermoelectric generator reported a high efficiency performance of 4.6%. The system had a vacuum glass enclosure, a flat panel (absorber), thermoelectric generator and water circulation for the cold side. The theoretical and numerical approach of this current study validated the experimental results from Kraemer's study to a high degree. The numerical simulation process utilizes a two-stage approach in ANSYS software for Fluent and Thermal-Electric Systems. The solar load model technique uses solar radiation under AM 1.5G conditions in Fluent. This analytical model applies Dr. Ho Sung Lee's theory of optimal design to improve the performance of the STEG system by using dimensionless parameters. Applying this theory, using two cover glasses and radiation shields, the STEG model can achieve a highest efficiency of 7%.

Fiscal 1976 Sunshine Project result report. R and D on solar heat power generation system (R and D on tower solar collection system); 1976 nendo taiyonetsu hatsuden system no kenkyu kaihatsu seika hokokusho. Tower shuko hoshiki system no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-05-27

This report describes the fiscal 1976 research result on tower solar collection system for solar heat power generation systems, and summarizes main specifications of the subsystem, equipment and control of the 1,000kW pilot plant. Based on daily and monthly long-time simulation, various programs were prepared for power generation, heat storage and operation rate of equipment, and real arrangements for total simulation were made. The output fluctuation rate less than 1%/min was obtained by studying a control system flexible for drastic fluctuation of solar radiation using the newly prepared dynamic characteristic equation for a steam loop. 10kW solar collection test was carried out using a pancake type heat absorber. Practical basic analysis was made on a heliostat driving system. A cavity type heat absorber was adopted in consideration of cost, operability and heat discharge. Based on thermal characteristics of a heat storage type heat exchanger using molten salt as heat medium, basic experiment was made on a compact latent heat type heat exchanger. Basic studies were also made on reflector, selective absorption surface and heat storage material. (NEDO)

Solar hot-water generation and heating - Kombi-Kompakt+

International Nuclear Information System (INIS)

Haller, M.; Vogelsanger, P.

2005-01-01

This final report for the Swiss Federal Office of Energy (SFOE) describes new testing facilities at the Institute for Solar Technology in Rapperswil, Switzerland, that allow the testing of solar systems the whole year through. The systems tested feature the combined generation of heat for hot water storage vessels and heat for space heating. The test method used, the Concise Cycle Test (CCT) is described. The results of tests made on a large number of systems demonstrate that it is especially important to have a test system that allows the solar market to be protected from unsatisfactory systems. Good co-operation with manufactures is noted. As the test method includes tests with secondary energy sources such as oil or gas, certain problems in this area were discovered and corrected. Further tests are to be made with systems using biomass as a secondary source of heat

Large solar energy systems within IEA task 14

NARCIS (Netherlands)

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

1996-01-01

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

Western Wind and Solar Integration Study Phase 3A: Low Levels of Synchronous Generation

Energy Technology Data Exchange (ETDEWEB)

Miller, Nicholas W. [GE Energy Management, Atlanta, GA (United States); Leonardi, Bruno [GE Energy Management, Atlanta, GA (United States); D' Aquila, Robert [GE Energy Management, Atlanta, GA (United States); Clark, Kara [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2015-11-17

The stability of the North American electric power grids under conditions of high penetrations of wind and solar is a significant concern and possible impediment to reaching renewable energy goals. The 33% wind and solar annual energy penetration considered in this study results in substantial changes to the characteristics of the bulk power system. This includes different power flow patterns, different commitment and dispatch of existing synchronous generation, and different dynamic behavior from wind and solar generation. The Western Wind and Solar Integration Study (WWSIS), sponsored by the U.S. Department of Energy, is one of the largest regional solar and wind integration studies to date. In multiple phases, it has explored different aspects of the question: Can we integrate large amounts of wind and solar energy into the electric power system of the West? The work reported here focused on the impact of low levels of synchronous generation on the transient stability performance in one part of the region in which wind generation has displaced synchronous thermal generation under highly stressed, weak system conditions. It is essentially an extension of WWSIS-3. Transient stability, the ability of the power system to maintain synchronism among all elements following disturbances, is a major constraint on operations in many grids, including the western U.S. and Texas systems. These constraints primarily concern the performance of the large-scale bulk power system. But grid-wide stability concerns with high penetrations of wind and solar are still not thoroughly understood. This work focuses on 'traditional' fundamental frequency stability issues, such as maintaining synchronism, frequency, and voltage. The objectives of this study are to better understand the implications of low levels of synchronous generation and a weak grid on overall system performance by: 1) Investigating the Western Interconnection under conditions of both high renewable

Retrofitting a Geothermal Plant with Solar and Storage to Increase Power Generation

Energy Technology Data Exchange (ETDEWEB)

Zhu, Guangdong [National Renewable Energy Laboratory (NREL), Golden, CO (United States); McTigue, Joshua Dominic P [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Turchi, Craig S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Castro, Jose [Coso Operating Co.; Mungas, Greg [Hyperlight Energy; Kramer, Nick [Hyperlight Energy; King, John [Hyperlight Energy

2017-10-04

Solar hybridization using concentrating solar power (CSP) can be an effective approach to augment the power generation and power cycle efficiency of a geothermal power plant with a declining resource. Thermal storage can further increase the dispatchability of a geothermal/solar hybrid system, which is particularly valued for a national grid with high renewable penetration. In this paper, a hybrid plant design with thermal storage is proposed based on the requirements of the Coso geothermal field in China Lake, California. The objective is to increase the power production by 4 MWe. In this system, a portion of the injection brine is recirculated through a heat exchanger with the solar heat transfer fluid, before being mixed with the production well brine. In the solar heating loop the brine should be heated to at least 155 degrees C to increase the net power. The solar field and storage were sized based on solar data for China Lake. Thermal storage is used to store excess power at the high-solar-irradiation hours and generate additional power during the evenings. The solar field size, the type and capacity of thermal storage and the operating temperatures are critical factors in determining the most economic hybrid system. Further investigations are required to optimize the hybrid system and evaluate its economic feasibility.

Performance tests and efficiency analysis of Solar Invictus 53S - A parabolic dish solar collector for direct steam generation

Science.gov (United States)

Jamil, Umer; Ali, Wajahat

2016-05-01

This paper presents the results of performance tests conducted on Solar Invictus 53S `system'; an economically effective solar steam generation solution designed and developed by ZED Solar Ltd. The system consists of a dual axis tracking parabolic solar dish and bespoke cavity type receiver, which works as a Once Through Solar Steam Generator `OTSSG' mounted at the focal point of the dish. The overall performance and efficiency of the system depends primarily on the optical efficiency of the solar dish and thermal efficiency of the OTSSG. Optical testing performed include `on sun' tests using CCD camera images and `burn plate' testing to evaluate the sunspot for size and quality. The intercept factor was calculated using a colour look-back method to determine the percentage of solar rays focused into the receiver. Solar dish tracking stability tests were carried out at different times of day to account for varying dish elevation angles and positions, movement of the sunspot centroid was recorded and logged using a CCD camera. Finally the overall performance and net solar to steam efficiency of the system was calculated by experimentally measuring the output steam parameters at varying Direct Normal Insolation (DNI) levels at ZED Solar's test facility in Lahore, Pakistan. Thermal losses from OTSSG were calculated using the known optical efficiency and measured changes in output steam enthalpy.

Dynamic voltage stability of a distribution system with high penetration of grid-connected photovoltaic type solar generators

Directory of Open Access Journals (Sweden)

Zetty Adibah Kamaruzzaman

2016-06-01

Full Text Available This paper presents the impact of grid-connected photovoltaic (PV generator on dynamic voltage stability of a power distribution system by considering solar intermittency, PV penetration level, and contingencies such as line outage and load increase. The IEEE 13 node test feeder is used as a test system, and a solar PV of 0.48 kV/0.5 MVA is integrated into the test system. Test results show that system voltage is stable at high PV penetration levels. Increase in load causes voltage instability, in which voltage drops below its allowable operating limit. Thus, increase in PV penetration level does not improve system voltage stability because the system experiences voltage collapse during line outage.

Assessing the Structural, Driver and Economic Impacts of Traffic Pole Mounted Wind Power Generator and Solar Panel Hybrid System

Science.gov (United States)

2012-06-01

This project evaluates the physical and economic feasibility of using existing traffic infrastructure to mount wind power : generators. Some possible places to mount a light weight wind generator and solar panel hybrid system are: i) Traffic : signal...

Mushrooms as Efficient Solar Steam-Generation Devices.

Science.gov (United States)

Xu, Ning; Hu, Xiaozhen; Xu, Weichao; Li, Xiuqiang; Zhou, Lin; Zhu, Shining; Zhu, Jia

2017-07-01

Solar steam generation is emerging as a promising technology, for its potential in harvesting solar energy for various applications such as desalination and sterilization. Recent studies have reported a variety of artificial structures that are designed and fabricated to improve energy conversion efficiencies by enhancing solar absorption, heat localization, water supply, and vapor transportation. Mushrooms, as a kind of living organism, are surprisingly found to be efficient solar steam-generation devices for the first time. Natural and carbonized mushrooms can achieve ≈62% and ≈78% conversion efficiencies under 1 sun illumination, respectively. It is found that this capability of high solar steam generation is attributed to the unique natural structure of mushroom, umbrella-shaped black pileus, porous context, and fibrous stipe with a small cross section. These features not only provide efficient light absorption, water supply, and vapor escape, but also suppress three components of heat losses at the same time. These findings not only reveal the hidden talent of mushrooms as low-cost materials for solar steam generation, but also provide inspiration for the future development of high-performance solar thermal conversion devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research and development of evaluation system for photovoltaic power generation system. Survey on research and development of solar cell evaluation system; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. Taiyo denchi hyoka system no kenkyu kaihatsu chosa

Energy Technology Data Exchange (ETDEWEB)

Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

This paper reports the survey results on R and D of solar cell evaluation systems in fiscal 1994. The performance/reliability evaluation subcommittee continuously analyzed technical issues and discussed solution measures from the last fiscal year. On development of performance evaluation methods, improvement of measurement accuracy for laminated solar cells is the study issue to be solved. Although laminated solar cells are measured by multiple light source solar simulator, difficult spectrum compensation causes measurement errors. Collection and analysis of data for determining atmospheric conditions, and outdoor measurement experiment under the atmospheric conditions for reference solar light were carried out. The study on incident angle characteristics of laminated solar cells clarified that the deviation from COS characteristics is 1.0% or less at an incident angle of 30{degree}. The study on generated energy in solar cell module level in field clarified that generated energy and generation efficiency are proportional to intensity of solar radiation. 1 tab.

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.

Economic aspects of Solar Thermal Technologies for electricity generation

International Nuclear Information System (INIS)

Meinecke, W.

1993-01-01

Economic results of German studies are presented, which compare the four solar thermal technologies for electricity generation (parabolic trough collector system, central receiver system, parabolic dish/Stirling system, solar chimney plant). These studies were carried out by Interatom (today Siemens/KWU) in Bergisch Gladbach, Flachglas Solartechnik in Koln and Schlaich Bergermann and Partner in Stuggart under contract of DLR in Koln. Funds were made available by the German Ministry of Research and Development (BMFT). The results indicate that all of the investigated technologies have the potential to reduce the generating costs and that in the future costs of below 0.30 DM/kWh could be expected under excellent insolation conditions (e.G. 2850 kWh/m''2 a direct insolation as in California/USA). (Author) 25 refs

Analysis of the solar/wind resources in Southern Spain for optimal sizing of hybrid solar-wind power generation systems

Science.gov (United States)

Quesada-Ruiz, S.; Pozo-Vazquez, D.; Santos-Alamillos, F. J.; Lara-Fanego, V.; Ruiz-Arias, J. A.; Tovar-Pescador, J.

2010-09-01

A drawback common to the solar and wind energy systems is their unpredictable nature and dependence on weather and climate on a wide range of time scales. In addition, the variation of the energy output may not match with the time distribution of the load demand. This can partially be solved by the use of batteries for energy storage in stand-alone systems. The problem caused by the variable nature of the solar and wind resources can be partially overcome by the use of energy systems that uses both renewable resources in a combined manner, that is, hybrid wind-solar systems. Since both resources can show complementary characteristics in certain location, the independent use of solar or wind systems results in considerable over sizing of the batteries system compared to the use of hybrid solar-wind systems. Nevertheless, to the day, there is no single recognized method for properly sizing these hybrid wind-solar systems. In this work, we present a method for sizing wind-solar hybrid systems in southern Spain. The method is based on the analysis of the wind and solar resources on daily scale, particularly, its temporal complementary characteristics. The method aims to minimize the size of the energy storage systems, trying to provide the most reliable supply.

High-Efficiency, Multijunction Solar Cells for Large-Scale Solar Electricity Generation

Science.gov (United States)

Kurtz, Sarah

2006-03-01

A solar cell with an infinite number of materials (matched to the solar spectrum) has a theoretical efficiency limit of 68%. If sunlight is concentrated, this limit increases to about 87%. These theoretical limits are calculated using basic physics and are independent of the details of the materials. In practice, the challenge of achieving high efficiency depends on identifying materials that can effectively use the solar spectrum. Impressive progress has been made with the current efficiency record being 39%. Today's solar market is also showing impressive progress, but is still hindered by high prices. One strategy for reducing cost is to use lenses or mirrors to focus the light on small solar cells. In this case, the system cost is dominated by the cost of the relatively inexpensive optics. The value of the optics increases with the efficiency of the solar cell. Thus, a concentrator system made with 35%- 40%-efficient solar cells is expected to deliver 50% more power at a similar cost when compare with a system using 25%-efficient cells. Today's markets are showing an opportunity for large concentrator systems that didn't exist 5-10 years ago. Efficiencies may soon pass 40% and ultimately may reach 50%, providing a pathway to improved performance and decreased cost. Many companies are currently investigating this technology for large-scale electricity generation. The presentation will cover the basic physics and more practical considerations to achieving high efficiency as well as describing the current status of the concentrator industry. This work has been authored by an employee of the Midwest Research Institute under Contract No. DE- AC36-99GO10337 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow

Techno-economic evaluation of concentrating solar power generation in India

International Nuclear Information System (INIS)

Purohit, Ishan; Purohit, Pallav

2010-01-01

The Jawaharlal Nehru National Solar Mission (JNNSM) of the recently announced National Action Plan on Climate Change (NAPCC) by the Government of India aims to promote the development and use of solar energy for power generation and other uses with the ultimate objective of making solar competitive with fossil-based energy options. The plan includes specific goals to (a) create an enabling policy framework for the deployment of 20,000 MW of solar power by 2022; (b) create favourable conditions for solar manufacturing capability, particularly solar thermal for indigenous production and market leadership; (c) promote programmes for off grid applications, reaching 1000 MW by 2017 and 2000 MW by 2022, (d) achieve 15 million m 2 solar thermal collector area by 2017 and 20 million by 2022, and (e) deploy 20 million solar lighting systems for rural areas by 2022. The installed capacity of grid interactive solar power projects were 6 MW until October 2009 that is far below from their respective potential. In this study, a preliminary attempt towards the technical and economic assessment of concentrating solar power (CSP) technologies in India has been made. To analyze the techno-economic feasibility of CSP technologies in Indian conditions two projects namely PS-10 (based on power tower technology) and ANDASOL-1 (based on parabolic trough collector technology) have been taken as reference cases for this study. These two systems have been simulated at several Indian locations. The preliminary results indicate that the use of CSP technologies in India make financial sense for the north-western part of the country (particularly in Rajasthan and Gujarat states). Moreover, internalization of secondary benefits of carbon trading under clean development mechanism of the Kyoto Protocol further improves the financial feasibility of CSP systems at other locations considered in this study. It may be noted that the locations blessed with annual direct solar radiation more than 1800 k

Prospect of solar-PV/biogas/diesel generator hybrid energy system of an off-grid area in Bangladesh

Science.gov (United States)

Mandal, Soumya; Yasmin, Hosna; Sarker, M. R. I.; Beg, M. R. A.

2017-12-01

The study presents an analysis and suggests about how renewable sources of energy can be an alternative option to produce electricity in an off-grid area. A case study is done by surveying 235 households in an off-grid area. Techno-economic analysis of the hybrid energy system is employed by using Hybrid Optimization of Multiple Energy Resources (HOMER) software. Four solar-PV modules (each of 1kW), two biogas generators (each of 3kW), three diesel generators (each of 5kW), five batteries (each of 160 Ah) and 5kW converter is found to be the best configuration in terms of Cost of Energy (COE), environmental conditions and Renewable Fraction (RF). The Cost of Energy (COE), Net Present Cost (NPC), capital cost of this configuration is found BDT15.382, BDT10007224, and BDT2582433 respectively. The renewable fraction of this system is found 75% which indicates a lower emission compared with thegrid based system and stand-alone diesel system. Although the COE is higher than grid electricity, this system offers a cheaper option than using kerosene oil and solar home systems (SHSs).

Performance analysis of dish solar stirling power system; Stirling engine wo mochiita taiyonetsu hatsuden system no seino yosoku

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, K; Yamaguchi, I [Meiji University, Tokyo (Japan); Naito, Y; Momose, Y [Aisin Seiki Co. Ltd., Aichi (Japan)

1996-10-27

In order to estimate the performance of the dish solar Stirling power system, matching and control of each component system were studied, and the performance of the 25kWe class power system was estimated on the basis of direct solar radiation measured in Miyako island, Okinawa. Application of a Stirling engine to solar heat power generation is highly effective in spite of its small scale. The total system is composed of a converging system, heat receiver, engine/generator system and control system. As the simulation result, the generator output is nearly proportional to direct solar radiation, and the system efficiency approaches to a certain constant value with an increase in direct solar radiation. As accumulated solar radiation is large, the influence of slope error of the converging mirror is comparatively small. The optimum aperture opening ratio of the heat receiver determined on the basis of mean direct solar radiation (accumulated solar radiation/{Delta}t (simulated operation time of the system)), corresponds to the primary approximation of the opening ratio for a maximum total generated output under variable direct solar radiation. 6 refs., 6 figs., 1 tab.

Solar-generated steam for oil recovery: Reservoir simulation, economic analysis, and life cycle assessment

International Nuclear Information System (INIS)

Sandler, Joel; Fowler, Garrett; Cheng, Kris; Kovscek, Anthony R.

2014-01-01

Highlights: • Integrated assessment of solar thermal enhanced oil recovery (TEOR). • Analyses of reservoir performance, economics, and life cycle factors. • High solar fraction scenarios show economic viability for TEOR. • Continuous variable-rate steam injection meets the benchmarks set by conventional steam flood. - Abstract: The viability of solar thermal steam generation for thermal enhanced oil recovery (TEOR) in heavy-oil sands was evaluated using San Joaquin Valley, CA data. The effectiveness of solar TEOR was quantified through reservoir simulation, economic analysis, and life-cycle assessment. Reservoir simulations with continuous but variable rate steam injection were compared with a base-case Tulare Sand steamflood project. For equivalent average injection rates, comparable breakthrough times and recovery factors of 65% of the original oil in place were predicted, in agreement with simulations in the literature. Daily cyclic fluctuations in steam injection rate do not greatly impact recovery. Oil production rates do, however, show seasonal variation. Economic viability was established using historical prices and injection/production volumes from the Kern River oil field. For comparison, this model assumes that present day steam generation technologies were implemented at TEOR startup in 1980. All natural gas cogeneration and 100% solar fraction scenarios had the largest and nearly equal net present values (NPV) of $12.54 B and $12.55 B, respectively. Solar fraction refers to the steam provided by solar steam generation. Given its large capital cost, the 100% solar case shows the greatest sensitivity to discount rate and no sensitivity to natural gas price. Because there are very little emissions associated with day-to-day operations from the solar thermal system, life-cycle emissions are significantly lower than conventional systems even when the embodied energy of the structure is considered. We estimate that less than 1 g of CO 2 /MJ of refined

Drainback solar thermal systems

DEFF Research Database (Denmark)

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

2016-01-01

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

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.

A distributed big data storage and data mining framework for solar-generated electricity quantity forecasting

Science.gov (United States)

Wang, Jianzong; Chen, Yanjun; Hua, Rui; Wang, Peng; Fu, Jia

2012-02-01

Photovoltaic is a method of generating electrical power by converting solar radiation into direct current electricity using semiconductors that exhibit the photovoltaic effect. Photovoltaic power generation employs solar panels composed of a number of solar cells containing a photovoltaic material. Due to the growing demand for renewable energy sources, the manufacturing of solar cells and photovoltaic arrays has advanced considerably in recent years. Solar photovoltaics are growing rapidly, albeit from a small base, to a total global capacity of 40,000 MW at the end of 2010. More than 100 countries use solar photovoltaics. Driven by advances in technology and increases in manufacturing scale and sophistication, the cost of photovoltaic has declined steadily since the first solar cells were manufactured. Net metering and financial incentives, such as preferential feed-in tariffs for solar-generated electricity; have supported solar photovoltaics installations in many countries. However, the power that generated by solar photovoltaics is affected by the weather and other natural factors dramatically. To predict the photovoltaic energy accurately is of importance for the entire power intelligent dispatch in order to reduce the energy dissipation and maintain the security of power grid. In this paper, we have proposed a big data system--the Solar Photovoltaic Power Forecasting System, called SPPFS to calculate and predict the power according the real-time conditions. In this system, we utilized the distributed mixed database to speed up the rate of collecting, storing and analysis the meteorological data. In order to improve the accuracy of power prediction, the given neural network algorithm has been imported into SPPFS.By adopting abundant experiments, we shows that the framework can provide higher forecast accuracy-error rate less than 15% and obtain low latency of computing by deploying the mixed distributed database architecture for solar-generated electricity.

Highly Flexible and Efficient Solar Steam Generation Device.

Science.gov (United States)

Chen, Chaoji; Li, Yiju; Song, Jianwei; Yang, Zhi; Kuang, Yudi; Hitz, Emily; Jia, Chao; Gong, Amy; Jiang, Feng; Zhu, J Y; Yang, Bao; Xie, Jia; Hu, Liangbing

2017-08-01

Solar steam generation with subsequent steam recondensation has been regarded as one of the most promising techniques to utilize the abundant solar energy and sea water or other unpurified water through water purification, desalination, and distillation. Although tremendous efforts have been dedicated to developing high-efficiency solar steam generation devices, challenges remain in terms of the relatively low efficiency, complicated fabrications, high cost, and inability to scale up. Here, inspired by the water transpiration behavior of trees, the use of carbon nanotube (CNT)-modified flexible wood membrane (F-Wood/CNTs) is demonstrated as a flexible, portable, recyclable, and efficient solar steam generation device for low-cost and scalable solar steam generation applications. Benefitting from the unique structural merits of the F-Wood/CNTs membrane-a black CNT-coated hair-like surface with excellent light absorbability, wood matrix with low thermal conductivity, hierarchical micro- and nanochannels for water pumping and escaping, solar steam generation device based on the F-Wood/CNTs membrane demonstrates a high efficiency of 81% at 10 kW cm -2 , representing one of the highest values ever-reported. The nature-inspired design concept in this study is straightforward and easily scalable, representing one of the most promising solutions for renewable and portable solar energy generation and other related phase-change applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The space-age solar system

International Nuclear Information System (INIS)

Baugher, J.F.

1988-01-01

This book is a description of the sun, planets, moons, asteroids, and comets in the solar system. Discussion is based heavily on results obtained from recent space probes to Mercury, Venus, Mars Jupiter, Saturn, and Uranus. Offers detailed descriptions of the moons of Jupiter and Saturn, and the results of the recent probes of Halley's comet. A discussion of meteorites leads to a description of the current models of the solar system. Introductory chapters present theories of the solar system from the ancient Greeks to the present day. Other topics covered include the sun, its structure, and how it generates energy; the surfaces, internal structures, and histories of the planets, from innermost Mercury to farthest Pluto, and their moons

Next Generation Solar Collectors for CSP

Energy Technology Data Exchange (ETDEWEB)

Molnar, Attila [3M Company, St. Paul, MN (United States); Charles, Ruth [3M Company, St. Paul, MN (United States)

2014-07-31

The intent of “Next Generation Solar Collectors for CSP” program was to develop key technology elements for collectors in Phase 1 (Budget Period 1), design these elements in Phase 2 (Budget Period 2) and to deploy and test the final collector in Phase 3 (Budget Period 3). 3M and DOE mutually agreed to terminate the program at the end of Budget Period 1, primarily due to timeline issues. However, significant advancements were achieved in developing a next generation reflective material and panel that has the potential to significantly improve the efficiency of CSP systems.

Photovoltaic Solar Energy Generation

CERN Document Server

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

2005-01-01

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

Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

DEFF Research Database (Denmark)

Heide, Dominik; Greiner, Martin; von Bremen, Lüder

The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption....... The required balancing power turns out to be 25% of the average hourly load. These numbers are in agreement with current hydro storage lakes in Scandinavia and the Alps, as well as with potential hydrogen storage in mostly North-German salt caverns....

Reduced storage and balancing needs in a fully renewable European power system with excess wind and solar power generation

DEFF Research Database (Denmark)

Heide, Dominik; Greiner, Martin; von Bremen, Lüder

2011-01-01

The storage and balancing needs of a simplified European power system, which is based on wind and solar power generation only, are derived from an extensive weather-driven modeling of hourly power mismatches between generation and load. The storage energy capacity, the annual balancing energy...... and the balancing power are found to depend significantly on the mixing ratio between wind and solar power generation. They decrease strongly with the overall excess generation. At 50% excess generation the required long-term storage energy capacity and annual balancing energy amount to 1% of the annual consumption....... The required balancing power turns out to be 25% of the average hourly load. These numbers are in agreement with current hydro storage lakes in Scandinavia and the Alps, as well as with potential hydrogen storage in mostly North-German salt caverns....

Performance of a compact solar absorption cooling system

International Nuclear Information System (INIS)

Mulyanef; Kamaruzzaman Sopian

2006-01-01

This paper describes the performance of a compact solar absorption system. Purpose of compact solar is collector, generator and condenser in one unit. At present, two types of absorption cooling systems are marketed: the lithium bromide-water system and the ammonia-water system. In the lithium bromide-water system, water vapor is the refrigerant and ammonia water system where ammonia is the refrigerant. In addition, the ammonia-water system requires higher generator temperature 120 o C to 150 o C than a flat-plate solar collector can provide without special techniques. The lithium bromide-water system operates satisfactorily at a generator temperature of 75 o C to 100 o C, achievable by a flat-plate collector. The lithium bromide-water system also has a higher COP than the ammonia-water system. The disadvantage of the lithium bromide-water systems is that the evaporators cannot operate at temperature below 0 o C since the refrigerant is water. The Coefficient of Performance (COP) system is 0.62 and the concentration of LiBr-H 2 O is 50%

The characteristic analysis of the solar energy photovoltaic power generation system

Science.gov (United States)

Liu, B.; Li, K.; Niu, D. D.; Jin, Y. A.; Liu, Y.

2017-01-01

Solar energy is an inexhaustible, clean, renewable energy source. Photovoltaic cells are a key component in solar power generation, so thorough research on output characteristics is of far-reaching importance. In this paper, an illumination model and a photovoltaic power station output power model were established, and simulation analysis was conducted using Matlab and other software. The analysis evaluated the condition of solar energy resources in the Baicheng region in the western part of Jilin province, China. The characteristic curve of the power output from a photovoltaic power station was obtained by simulation calculation. It was shown that the monthly average output power of the photovoltaic power station is affected by seasonal changes; the output power is higher in summer and autumn, and lower in spring and winter.

solaR: Solar Radiation and Photovoltaic Systems with R

Directory of Open Access Journals (Sweden)

Oscar Perpiñan Lamigueiro

2012-08-01

Full Text Available The solaR package allows for reproducible research both for photovoltaics (PV systems performance and solar radiation. It includes a set of classes, methods and functions to calculate the sun geometry and the solar radiation incident on a photovoltaic generator and to simulate the performance of several applications of the photovoltaic energy. This package performs the whole calculation procedure from both daily and intradaily global horizontal irradiation to the final productivity of grid-connected PV systems and water pumping PV systems.It is designed using a set of S4 classes whose core is a group of slots with multivariate time series. The classes share a variety of methods to access the information and several visualization methods. In addition, the package provides a tool for the visual statistical analysis of the performance of a large PV plant composed of several systems.Although solaR is primarily designed for time series associated to a location defined by its latitude/longitude values and the temperature and irradiation conditions, it can be easily combined with spatial packages for space-time analysis.

Design and Analysis of Hybrid Solar Lighting and Full-Spectrum Solar Energy Systems

International Nuclear Information System (INIS)

Muhs, J.D.

2001-01-01

This paper describes a systems-level design and analysis of a new approach for improving the energy efficiency and affordability of solar energy in buildings, namely, hybrid solar lighting and full-spectrum solar energy systems. By using different portions of the solar spectrum simultaneously for multiple end-use applications in buildings, the proposed system offers unique advantages over other alternatives for using sunlight to displace electricity (conventional topside daylighting and solar technologies). Our preliminary work indicates that hybrid solar lighting, a method of collecting and distributing direct sunlight for lighting purposes, will alleviate many of the problems with passive daylighting systems of today, such as spatial and temporal variability, glare, excess illumination, cost, and energy efficiency. Similarly, our work suggests that the most appropriate use of the visible portion of direct, nondiffuse sunlight from an energy-savings perspective is to displace electric light rather than generate electricity. Early estimates detailed in this paper suggest an anticipated system cost of well under$2.0/Wp and 5-11(cents)/kWh for displaced and generated electricity in single-story commercial building applications. Based on a number of factors discussed in the paper, including sunlight availability, building use scenarios, time-of-day electric utility rates, cost, and efficacy of the displaced electric lights, the simple payback of this approach in many applications could eventually be well under 5 years

Localized Spectral Analysis of Fluctuating Power Generation from Solar Energy Systems

Directory of Open Access Journals (Sweden)

Johan Nijs

2007-01-01

Full Text Available Fluctuations in solar irradiance are a serious obstacle for the future large-scale application of photovoltaics. Occurring regularly with the passage of clouds, they can cause unexpected power variations and introduce voltage dips to the power distribution system. This paper proposes the treatment of such fluctuating time series as realizations of a stochastic, locally stationary, wavelet process. Its local spectral density can be estimated from empirical data by means of wavelet periodograms. The wavelet approach allows the analysis of the amplitude of fluctuations per characteristic scale, hence, persistence of the fluctuation. Furthermore, conclusions can be drawn on the frequency of occurrence of fluctuations of different scale. This localized spectral analysis was applied to empirical data of two successive years. The approach is especially useful for network planning and load management of power distribution systems containing a high density of photovoltaic generation units.

Solar home systems in Nepal

Energy Technology Data Exchange (ETDEWEB)

Henryson, Jessica; Haakansson, Teresa

1999-04-01

Photovoltaic (PV) technology is a clean and environmentally friendly technology that does not require any fuels. The high reliability of operation and little need for maintenance makes it ideally suited for rural areas. Today PV systems are used in Nepal to power telecommunications centres, navigational aids, in pumping systems for irrigation and drinking water, and for household electrification. A solar home system consists of a PV module, a battery, a charge controller and 3-4 fluorescent light bulbs with fixture. The system provides power for lighting and operation of household appliances for several hours. The success of donor supported programs have shown that solar home systems can be a practical solution for many rural households. In 1996 the Government of Nepal launched a subsidy program for solar home systems, which dramatically has increased the demand for solar home systems among rural customers. This report includes a survey of 52 households with solar home systems in two villages. The field-study shows that the villagers are very happy with their systems and the technical performance of the systems in both villages is satisfactory. The study also shows the positive impact electricity has on education, health, income generation and quality of life. The beneficiaries of introducing electricity in remote areas are the children and the women 39 refs, 18 tabs. Examination paper

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

Energy Technology Data Exchange (ETDEWEB)

Hayes, J.; Andrejko, D.A.

1983-01-01

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

On the Path to SunShot. Emerging Issues and Challenges in Integrating High Levels of Solar into the Electrical Generation and Transmission System

Energy Technology Data Exchange (ETDEWEB)

Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Clark, Kara [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matt [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-05-01

This report examines how the bulk power system may need to evolve to accommodate the increased photovoltaic (PV) penetration resulting from achievement of the U.S. Department of Energy's SunShot cost targets. The variable and uncertain nature of PV-generated electricity presents grid-integration challenges. For example, the changing net load associated with high midday PV generation and low electricity demand can create 'overgeneration' that requires curtailment of PV output and reduces PV's value and cost-competitiveness. Accommodating the changes in net load resulting from increased variable generation requires enhancements to a power system's 'flexibility,' or ability to balance supply and demand over multiple time scales through options including changes in system operation, flexible generation, reserves from solar, demand response, energy storage, and enhanced transmission and regional coordination. For utility-scale PV with a baseline SunShot levelized cost of electricity (LCOE) of 6 cents/kWh, increasing the annual energy demand met by solar energy from 10% to 20% would increase the marginal LCOE of PV from 6 cents/kWh to almost 11 cents/kWh in a California grid system with limited flexibility. However, increasing system flexibility could minimize solar curtailment and keep PV cost-competitive at penetrations at least as high as 25%. In the longer term, energy storage technologies--such as concentrating solar power with thermal energy storage--could facilitate the cost-effective integration of even higher PV penetration. Efficient deployment of the grid-flexibility options needed to maintain solar's value will require various innovations, from the development of communication, control, and energy storage technologies to the implementation of new market rules and operating procedures.

Fiscal 1974 Sunshine Project result report. R and D on solar heat power generation system (R and D on tower solar collection system); 1974 nendo taiyonetsu hatsuden system no kenkyu kaihatsu seika hokokusho. Tower shuko hoshiki system no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-05-29

This report summarizes the fiscal 1974 research result on the solar heat power generation system with a tower light collection system. This system receives solar radiation energy by reflector group, and concentrates solar energy reflected by each reflector on the heat absorber mounted on the top of the tower. A ratio of the whole reflector group area to the receiving area of the heat absorber is called a concentration factor. The heat absorber converts concentrated dense radiation energy to thermal energy, and transfers heated thermal medium to the bottom of the tower to supply solar heat to a thermal plant after appropriate treatment. Based on the above basic idea, study was made on the total system and each subsystem, and some problems on component equipment and materials were extracted. After solving these problems and improving the whole system accuracy, these results are put to practical use for design and operation of an actual pilot plant. The main research items are as follows: feasibility study, simulation, element study, preparation of a 10kWT test equipment, and planning of a 1,000kW class pilot plant. (NEDO)

On the evolution, over four generations of paraboloidal dish solar thermal electric power systems

International Nuclear Information System (INIS)

Kaneff, S.

1993-01-01

After a decade of supplying useful power, the White Cliffs Paraboloidal Dish Solar Thermal Power Station (1100 km west of Sydney) is still operational and has provided major lessons and experience for subsequent developments; particularly for the Molokai/Alburquerque unit built jointly with Power Kinetics Inc (of Troy, USA) for the US Department of Energy. This has, in turn, given valuable guidance for the third generation system now nearing completion in Canberra and employing new collector concepts refined for commercial production and viability. Unlike much dish-oriented R and D, we consider systems of dish arrays supplying central plant as a more attractive proposition than assemblies of dish/engine units, for all but very small systems (<2 MWe). Development has recently commerce on the fourth generation technology which result in a 2 MWe dish system within 2 years, expected to be followed closely by a system of 10 to 20 MWe, preparatory to still larger systems, as the technology evolves and experience is gained. The rationale in this progression in based on the achievement of commercial cost-effectiveness in competition with other energy sources. The direction of evolution is becoming clear and application of the technology to broader spheres than electricity generation is likely. Because of the nature of production methods employed and the ease of installation, system implementation can be rapid. (Author) 29 refs

Solar atmosphere wave dynamics generated by solar global oscillating eigenmodes

Science.gov (United States)

Griffiths, M. K.; Fedun, V.; Erdélyi, R.; Zheng, R.

2018-01-01

The solar atmosphere exhibits a diverse range of wave phenomena, where one of the earliest discovered was the five-minute global acoustic oscillation, also referred to as the p-mode. The analysis of wave propagation in the solar atmosphere may be used as a diagnostic tool to estimate accurately the physical characteristics of the Sun's atmospheric layers. In this paper, we investigate the dynamics and upward propagation of waves which are generated by the solar global eigenmodes. We report on a series of hydrodynamic simulations of a realistically stratified model of the solar atmosphere representing its lower region from the photosphere to low corona. With the objective of modelling atmospheric perturbations, propagating from the photosphere into the chromosphere, transition region and low corona, generated by the photospheric global oscillations the simulations use photospheric drivers mimicking the solar p-modes. The drivers are spatially structured harmonics across the computational box parallel to the solar surface. The drivers perturb the atmosphere at 0.5 Mm above the bottom boundary of the model and are placed coincident with the location of the temperature minimum. A combination of the VALIIIC and McWhirter solar atmospheres are used as the background equilibrium model. We report how synthetic photospheric oscillations may manifest in a magnetic field free model of the quiet Sun. To carry out the simulations, we employed the magnetohydrodynamics code, SMAUG (Sheffield MHD Accelerated Using GPUs). Our results show that the amount of energy propagating into the solar atmosphere is consistent with a model of solar global oscillations described by Taroyan and Erdélyi (2008) using the Klein-Gordon equation. The computed results indicate a power law which is compared to observations reported by Ireland et al. (2015) using data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly.

Heat Transfer Phenomena in Concentrating Solar Power Systems.

Energy Technology Data Exchange (ETDEWEB)

Armijo, Kenneth Miguel; Shinde, Subhash L.

2016-11-01

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

Solar radiation - to - power generation models for one-axis tracking PV system with on-site measurements from Eskisehir, Turkey

Science.gov (United States)

Filik, Tansu; Başaran Filik, Ümmühan; Nezih Gerek, Ömer

2017-11-01

In this study, new analytic models are proposed for mapping on-site global solar radiation values to electrical power output values in solar photovoltaic (PV) panels. The model extraction is achieved by simultaneously recording solar radiation and generated power from fixed and tracking panels, each with capacity of 3 kW, in Eskisehir (Turkey) region. It is shown that the relation between the solar radiation and the corresponding electric power is not only nonlinear, but it also exhibits an interesting time-varying characteristic in the form of a hysteresis function. This observed radiation-to-power relation is, then, analytically modelled with three piece-wise function parts (corresponding to morning, noon and evening times), which is another novel contribution of this work. The model is determined for both fixed panels and panels with a tracking system. Especially the panel system with a dynamic tracker produces a harmonically richer (with higher values in general) characteristic, so higher order polynomial models are necessary for the construction of analytical solar radiation models. The presented models, characteristics of the hysteresis functions, and differences in the fixed versus solar-tracking panels are expected to provide valuable insight for further model based researches.

On the Path to SunShot - Emerging Issues and Challenges in Integrating High Levels of Solar into the Electrical Generation and Transmission System

Energy Technology Data Exchange (ETDEWEB)

Denholm, Paul [National Renewable Energy Lab. (NREL), Golden, CO (United States); Clark, Kara [National Renewable Energy Lab. (NREL), Golden, CO (United States); O' Connell, Matt [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-05-01

Increasing the use of grid-flexibility options (improved grid management, demand response, and energy storage) could enable 25% or higher penetration of PV at low costs (see Denholm et al. 2016). Considering the large-scale integration of solar into electric-power systems complicates the calculation of the value of solar. In fact a comprehensive examination reveals that the value of solar technologies—or any other power-system technology or operating strategy—can only be understood in the context of the generation system as a whole. This is well illustrated by analysis of curtailment at high PV penetrations within the bulk power and transmission systems. As the deployment of PV increases, it is possible that during some sunny midday periods due to limited flexibility of conventional generators, system operators would need to reduce (curtail) PV output in order to maintain the crucial balance between electric supply and demand. As a result, PV’s value and cost competitiveness would degrade. For example, for utility-scale PV with a baseline SunShot LCOE of 6¢/kWh, increasing the annual energy demand met by solar energy from 10% to 20% would increase the marginal LCOE of PV from 6¢/kWh to almost 11¢/kWh in a California grid system with limited flexibility. However, this loss of value could be stemmed by increasing system flexibility via enhanced control of variable-generation resources, added energy storage, and the ability to motivate more electricity consumers to shift consumption to lower-demand periods. The combination of these measures would minimize solar curtailment and keep PV cost-competitive at penetrations at least as high as 25%. Efficient deployment of the grid-flexibility options needed to maintain solar’s value will require various innovations, from the development of communication, control, and energy storage technologies to the implementation of new market rules and operating procedures.

Aluminum or steel? Mounting systems for solar generators - a practice report; Aluminium oder Stahl? Montagesysteme fuer Solargeneratoren - ein Praxisreport

Energy Technology Data Exchange (ETDEWEB)

Schnitzer, Sandy [Mounting Systems GmbH, Rangsdorf (Germany); Hannemann, Lydia

2013-10-01

Mounting systems for solar generators must be solid and reliable as long as possible so that they carry the modules. Which material is best? [German] Montagesysteme fuer Solargeneratoren muessen solide sein, damit sie moeglichst lange und zuverlaessig die Module tragen.

Solar generation: a blueprint for growing the PV market

International Nuclear Information System (INIS)

Cameron, M.; Stierstorfer, J.; Teske, S.; Aubrey, C.

2001-01-01

The rapid growth of the solar electricity market is discussed. The European Photovoltaic Industry Association and Greenpeace have recently collaborated on a long-term forecast of the global solar electricity market up to 2020 with predictions up to 2040; the conclusions from their joint study are the subject of this article. The paper is presented under the main sub-headings of (i) background to the collaboration; (ii) the Greenpeace perspective; (iii) the impact of solar electricity in the lives of consumers and job-seekers born today; (iv) solar generation-methods and assumptions (v) market growth rates; (vi) electricity generation; (vii) carbon dioxide emissions; (viii) projection to 2040; (ix) key results of the EPIA/Greenpeace analysis; (x) solar electricity as a vehicle for job creation and (xi) creating the conditions for optimizing the impact of solar electricity on future generations. A chart shows solar electricity job creation potential 2000-2020

Model and analysis of solar thermal generators to reduce the intermittency of photovoltaic systems with the use of spectrum splitting

Science.gov (United States)

Ayala, Silvana; Wu, Yuechen; Vorndran, Shelby; Santiago, Raphael P.; Kostuk, Raymond K.

2015-09-01

In this paper we introduce an approach to damping intermittency in photovoltaic (PV) system output due to fluctuations in solar illumination generated by use of a hybrid PV-thermal electric (TE) generation system. We describe the necessary constrains of the PV-TE system based on its thermodynamic characteristics. The basis for the approach is that the thermal time constant for the TE device is much longer than that of a PV cell. When used in combination with an optimized thermal storage device short periods of intermittency (several minutes) in PV output due to passing clouds can be compensated. A comparison of different spectrum splitting systems to efficiently utilize the incident solar spectrum between the PV and TE converters are also examined. The time-dependent behavior of a hybrid PV-TE converter with a thermal storage element is computed with SMARTS modeled irradiance data and compared to real weather and irradiation conditions for Tucson, Arizona.

Optimization of 10 kW solar photovoltaic – diesel generator hybrid energy system for different load factors at Jaisalmer location of Rajasthan, India

Science.gov (United States)

Saraswat, S. K.; Rao, K. V. S.

2018-03-01

Jaisalmer town in Rajasthan, India is having annual average solar insolation of 5.80 kWh/m2/day and 270 – 300 clear sky days in a year. A 10 kW off-grid hybrid energy system (HES) consisting of solar photovoltaic panels – diesel generator – bidirectional converter and batteries with zero percentage loss of load for Jaisalmer is designed using HOMER (version 3.4.3) software. Different system load factors of 0.33, 0.50, 0.67, 0.83 and 1 corresponding to fraction of running hours per day of the system are considered. The system is analyzed for all three aspects, namely, electrical, economic and emission point of view. Least levelized cost of electricity (LCOE) of Rs. 8.43/kWh is obtained at a load factor value of 0.5. If diesel generator alone (without Solar PV) is used to fulfil the demand for a load factor of 0.5the value of LCOE is obtained Rs.19.23/kWh. Comparison of results obtained for HES and diesel generator are made for load factor of 0.5 and 1.

Demonstrative study for the wind and solar hybrid power system. 2; Furyoku taiyoko hybrid hatsuden system ni kansuru jissho kenkyu

Energy Technology Data Exchange (ETDEWEB)

Kimura, Y; Sakuma, H; Ushiyama, I [Ashikaga Institute of Technology, Tochigi (Japan)

1996-10-27

In order to verify the complementary relationship between wind and solar energy, the long-term field test of the hybrid power system was conducted at the natural energy square of Ashikaga Institute of Technology. The solar cell blade windmill composed of a Savonius windmill and flexible solar cells applied to swept buckets was also prepared. As a result, the wind power generation was promising mainly in the winter period including the late fall and early spring, while solar one was stable all the year through although it was slightly poor in winter. Stable power generation was thus achieved by combining wind energy with solar energy. As the whole data of other wind and solar power generation systems at the square were analyzed for every month, the same conclusion as the solar cell blade windmill was obtained as follows: the wind power generation in Ashikaga area is promising in Nov.-March from the field test result for 16 months, solar power generation is stable all the year through, the hybrid power system is effective in Nov.-April, and the solar cell blade windmill is equivalent to the hybrid power system. 3 refs., 5 figs.

Adaptability of solar energy conversion systems on ships

Science.gov (United States)

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

2016-08-01

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

An assessment of the regional potential for solar power generation in EU-28

International Nuclear Information System (INIS)

Perpiña Castillo, Carolina; Batista e Silva, Filipe; Lavalle, Carlo

2016-01-01

In this study we aim at assessing the potential of European regions to solar power generation and its comparison with recent European Union (EU) incentives for the development of this renewable energy source. In this study we use a multi-criteria assessment (MCA) supported by Geographical Information System (GIS) to combine already existing information on solar radiation with other geographical factors such as slope, land use, urban extent and population distribution, as well as proximity to the power grid to generate a suitability map for photovoltaic (PV) power plants across the EU at high spatial resolution. A validation exercise showed that the resulting suitability map is a good predictor of appropriate locations for the deployment of PV power plants. The suitability map was in addition compared to the regional distribution of European funds for development of solar energy from the EU Cohesion policy (2007–2013 programme). Regions were classified according their overall suitability for solar energy power systems and the allocated solar investments by the EU Cohesion policy. This analysis allowed to identify potential mismatches between fund allocations and actual regional suitability for solar energy. It is recommended that future fund allocations take into account suitability criteria for solar energy for optimised results of public policies. - Highlights: • A European suitability map for the solar energy (PV) systems deployment is created. • PV systems can contribute in a sustainable energy production in many regions in EU. • There is no correlation among the EU investment and the suitability in solar energy. • Using marginal lands to place PV systems might avoid the uptake of agricultural land. • Validation of the EU suitability map demonstrated a satisfactory degree of accuracy.

High-Temperature High-Efficiency Solar Thermoelectric Generators

Energy Technology Data Exchange (ETDEWEB)

Baranowski, LL; Warren, EL; Toberer, ES

2014-03-01

Inspired by recent high-efficiency thermoelectric modules, we consider thermoelectrics for terrestrial applications in concentrated solar thermoelectric generators (STEGs). The STEG is modeled as two subsystems: a TEG, and a solar absorber that efficiently captures the concentrated sunlight and limits radiative losses from the system. The TEG subsystem is modeled using thermoelectric compatibility theory; this model does not constrain the material properties to be constant with temperature. Considering a three-stage TEG based on current record modules, this model suggests that 18% efficiency could be experimentally expected with a temperature gradient of 1000A degrees C to 100A degrees C. Achieving 15% overall STEG efficiency thus requires an absorber efficiency above 85%, and we consider two methods to achieve this: solar-selective absorbers and thermally insulating cavities. When the TEG and absorber subsystem models are combined, we expect that the STEG modeled here could achieve 15% efficiency with optical concentration between 250 and 300 suns.

Beam-Forming Concentrating Solar Thermal Array Power Systems

Science.gov (United States)

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

2016-01-01

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

Solar thermoelectric generators fabricated on a silicon-on-insulator substrate

International Nuclear Information System (INIS)

De Leon, Maria Theresa; Chong, Harold; Kraft, Michael

2014-01-01

Solar thermal power generation is an attractive electricity generation technology as it is environment-friendly, has the potential for increased efficiency, and has high reliability. The design, modelling, and evaluation of solar thermoelectric generators (STEGs) fabricated on a silicon-on-insulator substrate are presented in this paper. Solar concentration is achieved by using a focusing lens to concentrate solar input onto the membrane of the STEG. A thermal model is developed based on energy balance and heat transfer equations using lumped thermal conductances. This thermal model is shown to be in good agreement with actual measurement results. For a 1 W laser input with a spot size of 1 mm, a maximum open-circuit voltage of 3.06 V is obtained, which translates to a temperature difference of 226 °C across the thermoelements and delivers 25 µW of output power under matched load conditions. Based on solar simulator measurements, a maximum TEG voltage of 803 mV was achieved by using a 50.8 mm diameter plano-convex lens to focus solar input to a TEG with a length of 1000 µm, width of 15 µm, membrane diameter of 3 mm, and 114 thermocouples. This translates to a temperature difference of 18 °C across the thermoelements and an output power under matched load conditions of 431 nW. This paper demonstrates that by utilizing a solar concentrator to focus solar radiation onto the hot junction of a TEG, the temperature difference across the device is increased; subsequently improving the TEG’s efficiency. By using materials that are compatible with standard CMOS and MEMS processes, integration of solar-driven TEGs with on-chip electronics is seen to be a viable way of solar energy harvesting where the resulting microscale system is envisioned to have promising applications in on-board power sources, sensor networks, and autonomous microsystems. (paper)

Fiscal 1974 Sunshine Project result report. Research on solar energy utilization systems (total system); 1974 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Total system

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-03-01

The current most important solar energy utilization fields are solar energy power generation (solar heat and photovoltaic power generation), and solar heat cooling and heating. A solar heat power system collects or stores solar thermal energy as energy source of power systems, and converts it to electric power through heat exchange systems. To establish such system, not only R and D on a collector, absorption capsule, storage unit and heat transfer unit, but also complete study on an optimum system configuration and environmental impact are necessary. A photovoltaic power system converts solar energy to electric power directly by photoelectric conversion device such solar cell. Except specific local uses, drastic cost reduction and improvement of a conversion efficiency (at present 12-15%) and life (several years) are necessary for solar cells. Although a lot of solar heat cooling and heating systems is in practical use in Japan, for its further diffusion an important research task is development of heat collector excellent in efficiency, cost, life and maintainability. (NEDO)

Performance of the second generation solar heating system in the solar house of the Eindhoven University of Technology

NARCIS (Netherlands)

Bisschops, R.W.G.; van Koppen, C.W.J.; Veltkamp, W.B.; Ouden, den C.

1984-01-01

Summer 1981 a new solar heating system has been installed in the Solar House at the E.U.T. The principal features of the system are Philips VTR 261 evacuated tube collectors, integration of the auxiliary heater with the (stratified water) storage and application of the new, balanced flow control

Direct solar steam generation inside evacuated tube absorber

Directory of Open Access Journals (Sweden)

Khaled M. Bataineh

2016-12-01

Full Text Available Direct steam generation by solar radiation falling on absorber tube is studied in this paper. A system of single pipe covered by glass material in which the subcooled undergoes heating and evaporation process is analyzed. Mathematical equations are derived based on energy, momentum and mass balances for system components. A Matlab code is built to simulate the flow of water inside the absorber tube and determine properties of water along the pipe. Widely accepted empirical correlations and mathematical models of turbulent flow, pressure drop for single and multiphase flow, and heat transfer are used in the simulation. The influences of major parameters on the system performance are investigated. The pressure profiles obtained by present numerical solution for each operation condition (3 and 10 MPa matches very well experimental data from the DISS system of Plataforma Solar de Almería. Furthermore, results obtained by simulation model for pressure profiles are closer to the experimental data than those predicted by already existed other numerical model.

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.

A hybrid solar chemical looping combustion system with a high solar share

International Nuclear Information System (INIS)

Jafarian, Mehdi; Arjomandi, Maziar; Nathan, Graham J.

2014-01-01

Highlights: • A novel hybrid solar chemical looping combustion system is presented. • This hybrid CLC system integrates a CLC plant with a solar thermal energy plant. • The oxygen carrier particles are used for chemical and sensible thermal energy storage. • A solar cavity reactor is proposed for fuel reactor. • The calculations show a total solar share of around 60% can be achieved. - Abstract: A novel hybrid solar chemical looping combustion (Hy-Sol-CLC) is presented, in which the oxygen carrier particles in a CLC system are employed to provide thermal energy storage for concentrated solar thermal energy. This hybrid aims to take advantage of key features of a chemical looping combustion (CLC) system that are desirable for solar energy systems, notably their inherent chemical and sensible energy storage systems, the relatively low temperature of the “fuel” reactor (to which the concentrated solar thermal energy is added in a hybrid) relative to that of the final temperature of the product gas and the potential to operate the fuel reactor at a different pressure to the heated gas stream. By this approach, it is aimed to achieve high efficiency of the solar energy, infrastructure sharing, economic synergy, base load power generation and a high solar fraction of the total energy. In the proposed Hy-Sol-CLC system, a cavity solar receiver has been chosen for fuel reactor while for the storage of the oxygen carrier particles two reservoirs have been added to a conventional CLC. A heat exchanger is also proposed to provide independent control of the temperatures of the storage reservoirs from those of solar fuel and air reactors. The system is simulated using Aspen Plus software for the average diurnal profile of normal irradiance for Port Augusta, South Australia. The operating temperature of the fuel reactor, solar absorption efficiency, solar share, fraction of the solar thermal energy stored within the solar reactor, the fractions of sensible and

Behavior of hybrid concentrated photovoltaic-thermoelectric generator under variable solar radiation

DEFF Research Database (Denmark)

Mahmoudi Nezhad, Sajjad; Rezaniakolaei, Alireza; Rosendahl, Lasse Aistrup

2018-01-01

diversely versus changing the solar radiation and module temperature. Moreover, the thermal response of the TEG stabilizes temperature fluctuation of the hybrid module when the solar radiation rapidly changes. In this work, impact of the thermal contact resistance on the temperature profile and system...... and solved by finite volume algorithm. In spite of temperatures profile in the hybrid CPV-TEG module, as results of variation of solar irradiation, power generation and efficiency of the CPV and TEG under the transient condition are presented. The results show that efficiency of the TEG and CPV varies...

Fiscal 1976 Sunshine Project result report. R and D on solar heat power generation system (R and D on curved reflector light collection system); 1976 nendo taiyonetsu hatsuden system no kenkyu kaihatsu seika hokokusho. Kyokumen shuko hoshiki system no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

As a part of Sunshine Project, study was made on the solar heat power generation system using a solar collection system composed of plane and curved reflectors. In fiscal 1976, study was made on plant characteristics and plant operation by using system simulation program, and the concept design of the system was promoted. The reflectance of the plane reflector was improved up to 0.92 by remodeling the prototype collector fabricated in last fiscal year, and the prototype test facility of full-scale reflectors for 1,000kW solar power plant was prepared to obtain design data for large reflectors. The prototype heat collection loop control equipment which was prepared to simulate control of plant operation conditions according to solar radiation fluctuation, succeeded in prediction of solar radiation fluctuation within nearly 30min. New study was also made on a system using both accumulator and molten salt heat storage equipment, and each proper capacity for power plants was determined. In addition, high-temperature vapor generation for 2 hours was achieved by the prototype heat storage equipment using KCl-LiCl molten salt. (NEDO)

Solar Systems

Science.gov (United States)

1979-01-01

The solar collectors shown are elements of domestic solar hot water systems produced by Solar One Ltd., Virginia Beach, Virginia. Design of these systems benefited from technical expertise provided Solar One by NASA's Langley Research Center. The company obtained a NASA technical support package describing the d e sign and operation of solar heating equipment in NASA's Tech House, a demonstration project in which aerospace and commercial building technology are combined in an energy- efficient home. Solar One received further assistance through personal contact with Langley solar experts. The company reports that the technical information provided by NASA influenced Solar One's panel design, its selection of a long-life panel coating which increases solar collection efficiency, and the method adopted for protecting solar collectors from freezing conditions.

The performance of a combined solar photovoltaic (PV) and thermoelectric generator (TEG) system

DEFF Research Database (Denmark)

Bjørk, Rasmus; Nielsen, Kaspar Kirstein

2015-01-01

The performance of a combined solar photovoltaic (PV) and thermoelectric generator (TEG) system is examined using an analytical model for four different types of commercial PVs and a commercial bismuth telluride TEG. The TEG is applied directly on the back of the PV, so that the two devices have...... the same temperature. The PVs considered are crystalline Si (c-Si), amorphous Si (a-Si), copper indium gallium (di) selenide (CIGS) and cadmium telluride (CdTe) cells. The degradation of PV performance with temperature is shown to dominate the increase in power produced by the TEG, due to the low...... efficiency of the TEG. For c-Si, CIGS and CdTe PV cells the combined system produces a lower power and has a lower efficiency than the PV alone, whereas for an a-Si cell the total system performance may be slightly increased by the TEG....

Performance analysis of a solar-assisted swimming pool heating system

Energy Technology Data Exchange (ETDEWEB)

Alkhamis, A I; Sherif, S A [Miami Univ., Coral Gables, FL (United States). Dept. of Mechanical Engineering

1991-12-31

This paper discusses feasibility studies for a solar-assisted heating system using a computer simulation program. The solar heating is accomplished by employing hot water generated by heat exchange with the solar collector working fluid. The performance of the system is analysed from both thermodynamic and economic standpoints and general conclusions are reached. 17 refs., 7 figs.

A novel procedure for generating solar irradiance TSYs

Science.gov (United States)

Fanego, Vicente Lara; Rubio, Jesús Pulgar; Peruchena, Carlos M. Fernández; Romeo, Martín Gastón; Tejera, Sara Moreno; Santigosa, Lourdes Ramírez; Balderrama, Rita X. Valenzuela; Tirado, Luis F. Zarzalejo; Pantaleón, Diego Bermejo; Pérez, Manuel Silva; Contreras, Manuel Pavón; García, Ana Bernardos; Anarte, Sergio Macías

2017-06-01

Typical Solar Years (TSYs) are key parameters for the solar energy industry. In particular, TSYs are mainly used for the design and bankability analysis of solar projects. In essence, a TSY intends to describe the expected long-term behavior of the solar resource (direct and/or global irradiance) into a condensed period of one year at the specific location of interest. A TSY differs from a conventional Typical Meteorological Year (TMY) by its absence of meteorological variables other than solar radiation. Concerning the probability of exceedance (Pe) needed for bankability, various scenarios are commonly used, with Pe90, Pe95 or even Pe99 being most usually required as unfavorable scenarios, along with the most widely used median scenario (Pe50). There is no consensus in the scientific community regarding the methodology for generating TSYs for any Pe scenario. Furthermore, the application of two different construction methods to the same original dataset could produce differing TSYs. Within this framework, a group of experts has been established by the Spanish Association for Standardization and Certification (AENOR) in order to propose a method that can be standardized. The method developed by this working group, referred to as the EVA method, is presented in this contribution. Its evaluation shows that it provides reasonable results for the two main irradiance components (direct and global), with low errors in the annual estimations for any given Pe. The EVA method also preserves the long-term statistics when the computed TSYs for a specific Pe are expanded from the monthly basis used in the generation of the TSY to higher time resolutions, such as 1 hour, which are necessary for the precise energy simulation of solar systems.

Rural electrification with photovoltaic solar technology using solar home system; Eletrificacao rural com tecnologia solar fotovoltaica utilizando sistemas isolados autonomos

Energy Technology Data Exchange (ETDEWEB)

Salviano, Carlos Jose Caldas

1999-02-01

The utilization of solar energy, inexhaustible on the earthly scale of time, as heat and light source, today is one of the energetics alternatives more to confront the challenges of the new millennium. Remarkable is the impulse that power generation photovoltaic has received in Brazil. In Pernambuco, state of Brazil, the CELPE - Electric Power Company of Pernambuco, already implanted more than 750 photovoltaic solar home system (95 kW installed) for power supply to rural communities far from the grid connection that come across in commercial operation since 1994. Eight configurations were studied with modifications in their components (panel, battery and charge) with the objective to evaluate the performance and the adequacy of the size these configurations. The parameters utilized for this evaluation were: solar energy diary incident on the panel plat, diary efficiency generator, output voltage on the generator and state of charge the batteries bank. A system of data acquisition automated was fined to measure in real conditions the function of each components, the following parameters: solar radiation incident and temperature on the photovoltaic generator, voltage and generator current, batteries bank and charge and ambient temperature. About the configurations studied, it follows that analysis the operational of characteristics capacity and battery capacity of the SHS utilized, simulating the rural electrification conditions. It was possible to certify the adequate configurations for the load profile will be supply. (author)

Deployable Propulsion, Power and Communication Systems for Solar System Exploration

Science.gov (United States)

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

2017-01-01

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

Numerical approach to solar ejector-compression refrigeration system

Directory of Open Access Journals (Sweden)

Zheng Hui-Fan

2016-01-01

Full Text Available A model was established for solar ejector-compression refrigeration system. The influence of generator temperature, middle-temperature, and evaporator temperature on the performance of the refrigerant system was analyzed. An optimal generator temperature is found for maximal energy efficiency ratio and minimal power consumption.

The Cost-Optimal Distribution of Wind and Solar Generation Facilities in a Simplified Highly Renewable European Power System

Science.gov (United States)

Kies, Alexander; von Bremen, Lüder; Schyska, Bruno; Chattopadhyay, Kabitri; Lorenz, Elke; Heinemann, Detlev

2016-04-01

The transition of the European power system from fossil generation towards renewable sources is driven by different reasons like decarbonisation and sustainability. Renewable power sources like wind and solar have, due to their weather dependency, fluctuating feed-in profiles, which make their system integration a difficult task. To overcome this issue, several solutions have been investigated in the past like the optimal mix of wind and PV [1], the extension of the transmission grid or storages [2]. In this work, the optimal distribution of wind turbines and solar modules in Europe is investigated. For this purpose, feed-in data with an hourly temporal resolution and a spatial resolution of 7 km covering Europe for the renewable sources wind, photovoltaics and hydro was used. Together with historical load data and a transmission model , a simplified pan-European power power system was simulated. Under cost assumptions of [3] the levelized cost of electricity (LCOE) for this simplified system consisting of generation, consumption, transmission and backup units is calculated. With respect to the LCOE, the optimal distribution of generation facilities in Europe is derived. It is shown, that by optimal placement of renewable generation facilities the LCOE can be reduced by more than 10% compared to a meta study scenario [4] and a self-sufficient scenario (every country produces on average as much from renewable sources as it consumes). This is mainly caused by a shift of generation facilities towards highly suitable locations, reduced backup and increased transmission need. The results of the optimization will be shown and implications for the extension of renewable shares in the European power mix will be discussed. The work is part of the RESTORE 2050 project (Wuppertal Institute, Next Energy, University of Oldenburg), that is financed by the Federal Ministry of Education and Research (BMBF, Fkz. 03SFF0439A). [1] Kies, A. et al.: Kies, Alexander, et al

Comparative parameters of solar cells for power generation: test stand implementation using DSP

International Nuclear Information System (INIS)

Álvarez López, Ramón Antonio; García Angarita, Maritza Andrea

2014-01-01

The technologies used in solar modules are distinguished mainly by th eenergy conversion efficiency. Consequently, the module selection is critic to the long term performance of photovoltaic generating facility. Therefore, the selection must be supported by experimental results obtained under a specific operation condition. The article implements an experimentally test for obtain the characteristic parameters of a solar module, we analyze the energy conversion efficiency and other correlated parameters that directly affect the performance of a photovoltaic generator. The results show that the use of a rapid prototyping system using open hardware, such as TMS320F28335 development kit makes it easy to build a test photovoltaic generation systems. Latter justified by the low cost of such devices and ease of programming. (author)

An automated tool for solar power systems

International Nuclear Information System (INIS)

Natsheh, E.M.; Natsheh, A.R.; Albarbar, AH

2014-01-01

In this paper a novel model of smart grid-connected solar power system is developed. The model is implemented using MatLab/SIMULINK software package. Artificial neural network (ANN) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The dynamic behavior of the proposed model is examined under different operating conditions. Solar irradiance, and temperature data are gathered from a grid connected, 28.8 kW solar power system located in central Manchester. The developed system and its control strategy exhibit excellent performance with tracking efficiency exceed 94.5%. The proposed model and its control strategy offer a proper tool for smart grid performance optimization. (author)

Integrated solar energy system optimization

Science.gov (United States)

Young, S. K.

1982-11-01

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

Testing for Dark Matter Trapped in the Solar System

Science.gov (United States)

Krisher, Timothy P.

1996-01-01

We consider the possibility of dark matter trapped in the solar system in bound solar orbits. If there exist mechanisms for dissipating excess kinetic energy by an amount sufficient for generating bound solar orbits, then trapping of galactic dark matter might have taken place during formation of the solar system, or could be an ongoing process. Possible locations for acumulation of trapped dark matter are orbital resonances with the planets or regions in the outer solar system. It is posible to test for the presence of unseen matter by detecting its gravitational effects. Current results for dynamical limits obtained from analyses of planetary ephemeris data and spacecraft tracking data are presented. Possible future improvements are discussed.

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.

Intra-Hour Dispatch and Automatic Generator Control Demonstration with Solar Forecasting - Final Report

Energy Technology Data Exchange (ETDEWEB)

Coimbra, Carlos F. M. [Univ. of California, San Diego, CA (United States

2016-02-25

In this project we address multiple resource integration challenges associated with increasing levels of solar penetration that arise from the variability and uncertainty in solar irradiance. We will model the SMUD service region as its own balancing region, and develop an integrated, real-time operational tool that takes solar-load forecast uncertainties into consideration and commits optimal energy resources and reserves for intra-hour and intra-day decisions. The primary objectives of this effort are to reduce power system operation cost by committing appropriate amount of energy resources and reserves, as well as to provide operators a prediction of the generation fleet’s behavior in real time for realistic PV penetration scenarios. The proposed methodology includes the following steps: clustering analysis on the expected solar variability per region for the SMUD system, Day-ahead (DA) and real-time (RT) load forecasts for the entire service areas, 1-year of intra-hour CPR forecasts for cluster centers, 1-year of smart re-forecasting CPR forecasts in real-time for determination of irreducible errors, and uncertainty quantification for integrated solar-load for both distributed and central stations (selected locations within service region) PV generation.

Enhanced Solar-to-Hydrogen Generation with Broadband Epsilon-Near-Zero Nanostructured Photocatalysts

KAUST Repository

Tian, Yi

2017-05-08

The direct conversion of solar energy into fuels or feedstock is an attractive approach to address increasing demand of renewable energy sources. Photocatalytic systems relying on the direct photoexcitation of metals have been explored to this end, a strategy that exploits the decay of plasmonic resonances into hot carriers. An efficient hot carrier generation and collection requires, ideally, their generation to be enclosed within few tens of nanometers at the metal interface, but it is challenging to achieve this across the broadband solar spectrum. Here the authors demonstrate a new photocatalyst for hydrogen evolution based on metal epsilon-near-zero metamaterials. The authors have designed these to achieve broadband strong light confinement at the metal interface across the entire solar spectrum. Using electron energy loss spectroscopy, the authors prove that hot carriers are generated in a broadband fashion within 10 nm in this system. The resulting photocatalyst achieves a hydrogen production rate of 9.5 µmol h-1  cm-2 that exceeds, by a factor of 3.2, that of the best previously reported plasmonic-based photocatalysts for the dissociation of H2 with 50 h stable operation.

Analysis of Solar Energy Generation Capacity Using Hesitant Fuzzy Cognitive Maps

Directory of Open Access Journals (Sweden)

Veysel Coban

2017-01-01

Full Text Available Solar energy is an important and reliable source of energy. Better understanding the concepts and relationships of the factors that affect solar energy generation capacity can enhance the usage of solar energy. This understanding can lead investors and governors in their solar power investments. However, solar power generation process is complicated, and the relations among the factors are vague and hesitant. In this paper, a hesitant fuzzy cognitive map for solar energy generation is developed and used for modeling and analyzing the ambiguous relations. The concepts and the relationships among them are defined by using expertsr opinions. Different scenarios are formed and evaluated with the proposed model.

Steam generator design for solar towers using solar salt as heat transfer fluid

Science.gov (United States)

González-Gómez, Pedro Ángel; Petrakopoulou, Fontina; Briongos, Javier Villa; Santana, Domingo

2017-06-01

Since the operation of a concentrating solar power plant depends on the intermittent character of solar energy, the steam generator is subject to daily start-ups, stops and load variations. Faster start-up and load changes increase the plant flexibility and the daily energy production. However, it involves high thermal stresses on thick-walled components. Continuous operational conditions may eventually lead to a material failure. For these reasons, it is important to evaluate the transient behavior of the proposed designs in order to assure the reliability. The aim of this work is to analyze different steam generator designs for solar power tower plants using molten salt as heat transfer fluid. A conceptual steam generator design is proposed and associated heat transfer areas and steam drum size are calculated. Then, dynamic models for the main parts of the steam generator are developed to represent its transient performance. A temperature change rate that ensures safe hot start-up conditions is studied for the molten salt. The thermal stress evolution on the steam drum is calculated as key component of the steam generator.

Deployable Propulsion and Power Systems for Solar System Exploration

Science.gov (United States)

Johnson, Les; Carr, John

2017-01-01

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

Fiscal 1976 Sunshine Project result report. Research on solar energy utilization systems (total system); 1976 nendo taiyo energy riyo system chosa kenkyu seika hokokusho. Total system

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

For every solar energy utilization field, its background, feasibility, impact in practical use, and R and D policy in Japan were studied. Heating and hot water supply by solar energy are already practical because of less technical problems and reasonable profitability, and cooling is also practical as far as a technical viewpoint. At present, the technical level of solar heat power generation is in the stage of basic technology, however, in the future, development of economically reasonable systems will be demanded as well as establishment of its technology. The most difficult problem for realizing practical solar cell power generation systems is cost reduction. It is also another problem that a big demand of Si for solar cells further exceeds the current yield of Si in a semiconductor industry. A small-scale hybrid solar cell power generation system applicable to the roof of general residences is already feasible. Although a solar furnace is still poor in application to industrial fields, it is expected as the leading part for a future solar heat chemical industry. (NEDO)

Photovoltaic-wind hybrid autonomous generation systems in Mongolia

Energy Technology Data Exchange (ETDEWEB)

Dei, Tsutomu; Ushiyama, Izumi

2005-01-01

Two hybrid stand-alone (autonomous) power systems, each with wind and PV generation, were studied as installed at health clinics in semi-desert and mountainous region in Mongolia. Meteorological and system operation parameters, including power output and the consumption of the system, were generally monitored by sophisticated monitoring. However, where wind and solar site information was lacking, justifiable estimates were made. The results show that there is a seasonal complementary relationship between wind and solar irradiation in Tarot Sum. The users understood the necessity of Demand Side Management of isolated wind-PV generation system through technology transfer seminars and actually executed DSM at both sites. (author)

Power fluctuations suppression of stand-alone hybrid generation combining solar photovoltaic/wind turbine and fuel cell systems

International Nuclear Information System (INIS)

Ahmed, Nabil A.; Miyatake, Masafumi; Al-Othman, A.K.

2008-01-01

In this paper a hybrid energy system combining variable speed wind turbine, solar photovoltaic and fuel cell generation systems is presented to supply continuous power to residential power applications as stand-alone loads. The wind and photovoltaic systems are used as main energy sources while the fuel cell is used as secondary or back-up energy source. Three individual dc-dc boost converters are used to control the power flow to the load. A simple and cost effective control with dc-dc converters is used for maximum power point tracking and hence maximum power extracting from the wind turbine and the solar photovoltaic systems. The hybrid system is sized to power a typical 2 kW/150 V dc load as telecommunication power plants or ac residential power applications in isolated islands continuously throughout the year. The results show that even when the sun and wind are not available; the system is reliable and available and it can supply high-quality power to the load. The simulation results which proved the accuracy of the proposed controllers are given to demonstrate the availability of the proposed system in this paper. Also, a complete description of the management and control system is presented

Steam generation from solar energy

International Nuclear Information System (INIS)

Gozzi, M.

2001-01-01

The vapor for thermoelectric use is one of the most promoted methods for electric power generation from solar energy. The new plants are becoming more and more safe, and anyway in some cases the natural gas makes easy the production of electricity [it

Power Generation Potential and Cost of a Roof Top Solar PV System in Kathmandu, Nepal

Science.gov (United States)

Sanjel, N.; Zhand, A.

2017-12-01

The paper presents a comparative study of the 3 most used solar PV module technologies in Nepal, which are Si-mono-crystalline, Si-poly-crystalline and Si-amorphous. The aim of the paper is to present and discuss the recorded Global Solar Radiation, received in the Kathmandu valley by three different, Si-mono-crystalline, Si-poly-crystalline and Si-amorphous calibrated solar cell pyranometers and to propose the best-suited solar PV module technology for roof top solar PV systems inside the Kathmandu valley. Data recorded over the course of seven months, thus covering most of the seasonal meteorological conditions determining Kathmandu valley's global solar radiation reception are presented. The results indicate that the Si-amorphous pyranometer captured 1.56% more global solar radiation than the Si-mono-crystalline and 18.4% more than Si-poly-crystalline pyranometer over the course of seven months. Among the three pyranometer technologies the maximum and minimum cell temperature was measured by the Si-mono-crystalline pyranometer. Following the technical data and discussion, an economical analysis, using the versatile software tool PVSYST V5.01is used to calculate the life cycle costs of a 1kW roof top solar PV RAPS system, with battery storage, and a 1kW roof top solar PV grid connected system with no energy storage facility, through simulations, using average recorded global solar radiation data for the KTM valley and investigated market values for each solar PV module and peripheral equipment costs.

Very Short-term Nonparametric Probabilistic Forecasting of Renewable Energy Generation - with Application to Solar Energy

DEFF Research Database (Denmark)

Golestaneh, Faranak; Pinson, Pierre; Gooi, Hoay Beng

2016-01-01

Due to the inherent uncertainty involved in renewable energy forecasting, uncertainty quantification is a key input to maintain acceptable levels of reliability and profitability in power system operation. A proposal is formulated and evaluated here for the case of solar power generation, when only...... approach to generate very short-term predictive densities, i.e., for lead times between a few minutes to one hour ahead, with fast frequency updates. We rely on an Extreme Learning Machine (ELM) as a fast regression model, trained in varied ways to obtain both point and quantile forecasts of solar power...... generation. Four probabilistic methods are implemented as benchmarks. Rival approaches are evaluated based on a number of test cases for two solar power generation sites in different climatic regions, allowing us to show that our approach results in generation of skilful and reliable probabilistic forecasts...

Performance test of solar-assisted ejector cooling system

KAUST Repository

Huang, Bin-Juine

2014-03-01

A solar-assisted ejector cooling/heating system (SACH-2k) is built and test result is reported. The solar-driven ejector cooling system (ECS) is connected in series with an inverter-type air conditioner (IAC). Several advanced technologies are developed in SACH-k2, including generator liquid level control in ECS, the ECS evaporator temperature control, and optimal control of fan power in cooling tower of ECS. From the field test results, the generator liquid level control performs quite well and keeps stable performance of ejector. The ECS evaporator temperature control also performs satisfactorily to keep ejector performance normally under low or fluctuating solar radiation. The fan power control system cooling tower performs stably and reduces the power consumption dramatically without affecting the ECS performance. The test results show that the overall system COPo including power consumptions of peripheral increases from 2.94-3.3 (IAC alone) to 4.06-4.5 (SACH-k2), about 33-43%. The highest COPo is 4.5. © 2013 Elsevier Ltd and IIR. All rights reserved.

Deployable Propulsion, Power and Communications Systems for Solar System Exploration

Science.gov (United States)

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

2017-01-01

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

Dual-Axis Solar Tracking System for Maximum Power Production in ...

African Journals Online (AJOL)

Akorede

ABSTRACT: The power developed in a solar energy system depends fundamentally upon the ... for power generation. ... determined because they are functions of the solar angles that ..... able to withstand the weight and the blowing wind.

New Earth-abundant Materials for Large-scale Solar Fuels Generation.

Science.gov (United States)

Prabhakar, Rajiv Ramanujam; Cui, Wei; Tilley, S David

2018-05-30

The solar resource is immense, but the power density of light striking the Earth's surface is relatively dilute, necessitating large area solar conversion devices in order to harvest substantial amounts of power for renewable energy applications. In addition, energy storage is a key challenge for intermittent renewable resources such as solar and wind, which adds significant cost to these energies. As the majority of humanity's present-day energy consumption is based on fuels, an ideal solution is to generate renewable fuels from abundant resources such as sunlight and water. In this account, we detail our recent work towards generating highly efficient and stable Earth-abundant semiconducting materials for solar water splitting to generate renewable hydrogen fuel.

Automatic control of plants of direct steam generation with cylinder-parabolic solar collectors; Control automatico de plantas de generacion directa de vapor con colectores solares cilindro-parabolicos

Energy Technology Data Exchange (ETDEWEB)

Valenzuela Gutierrez, L.

2008-07-01

The main objective of this dissertation has been the contributions to the operation in automatic mode of a new generation of direct steam generation solar plants with parabolic-trough collectors. The dissertation starts introducing the parabolic-trough collectors solar thermal technology for the generation of process steam or steam for a Rankine cycle in the case of power generation generation, which is currently the most developed and commercialized technology. Presently, the parabolic-trough collectors technology is based on the configuration known as heat-exchanger system, based in the use of a heat transfer fluid in the solar field which is heated during the recirculation through the absorber tubes of the solar collectors, transferring later on the that thermal energy to a heat-exchanger for steam generation. Direct steam generation in the absorber tubes has always been shown as an ideal pathway to reduce generation cost by 15% and increase conversion efficiency by 20% (DISS, 1999). (Author)

Exploring the Trans-Neptunian Solar System

Science.gov (United States)

1998-01-01

A profound question for scientists, philosophers and, indeed, all humans concerns how the solar system originated and subsequently evolved. To understand the solar system's formation, it is necessary to document fully the chemical and physical makeup of its components today, particularly those parts thought to retain clues about primordial conditions and processes.] In the past decade, our knowledge of the outermost, or trans-neptunian, region of the solar system has been transformed as a result of Earth-based observations of the Pluto-Charon system, Voyager 2's encounter with Neptune and its satellite Triton, and recent discoveries of dozens of bodies near to or beyond the orbit of Neptune. As a class, these newly detected objects, along with Pluto, Charon, and Triton, occupy the inner region of a hitherto unexplored component of the solar system, the Kuiper Belt. The Kuiper Belt is believed to be a reservoir of primordial objects of the type that formed in the solar nebula and eventually accreted to form the major planets. The Kuiper Belt is also thought to be the source of short-period comets and a population of icy bodies, the Centaurs, with orbits among the giant planets. Additional components of the distant outer solar system, such as dust and the Oort comet cloud, as well as the planet Neptune itself, are not discussed in this report. Our increasing knowledge of the trans-neptunian solar system has been matched by a corresponding increase in our capabilities for remote and in situ observation of these distant regions. Over the next 10 to 15 years, a new generation of ground- and space-based instruments, including the Keck and Gemini telescopes and the Space Infrared Telescope Facility, will greatly expand our ability to search for and conduct physical and chemical studies on these distant bodies. Over the same time span, a new generation of lightweight spacecraft should become available and enable the first missions designed specifically to explore the icy

Force convective solar drying system

International Nuclear Information System (INIS)

Ruslan, M.H.; Othman, M.Y.; Baharuddin Yatim; Kamaruzzaman Sopian; Ibarahim, Z.

2006-01-01

This paper presents design and performance of V-groove back-pass solar collector for solar drying system. In this study three V-groove back-pass solar collector each with dimension of 4.6 m x 1.0 m x 0.15 m have been fabricated for solar drying system. An outdoor test at mean solar intensity for 600-800 Wm -2 by using 0.15m 3 s -1 of air flow rate which also been suggested by (Zeroul et al. 1994) was carried out at Solar Research Energy Park. Universiti Kebangsaan Malaysia. Analysis on the collector performance based on daily data was reported that the value of FR ) e and FRUL was 0.709 ± 0.001 and 5.89 ± 0.31 Wm -2o C -1 respectively with 60-70 o C of output temperature (Ruslan et al. 2001). The three V-groove collectors each with dimension 4.6 m x 0.15 m were connected in series array mounted on the roof of a solar assisted drying system. By using two electric fans of 85W and 2700 rpm each, the speed of air was regulated at 0.11 kgs -1 to 0.31 kgs -1 using a voltage regulator. Performance of the collector based on the thermal analysis showed that at mean daily solar radiation 700 Wm -2 , the output temperature of 52 o C to 73 o C could be achieved using 0.11-0.31 kgs -1 of flow rate. Thermal analysis also showed that the efficiencies of 45% to 61% could be obtains using the same flow rate and solar radiation. Analysis of daily data showed that for radiation from 300 Wm -2 to 1000 Wm -2 the power generated from the collector was within 1.5 kW to 8.9 kW. The study concluded that the levels of the levels of the solar radiation and flow rate used influenced the performance of the collector

Efficiency and entropy generation in fined tube solar collectors systems; Eficiencia e geracao de entropia em sistemas de tubos aletados coletores de energia solar

Energy Technology Data Exchange (ETDEWEB)

Santos, Marcio Bueno dos [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Lab. de Integracao e Testes; Saboya, Sergio Mourao [Instituto Tecnologico de Aeronautica, Sao Jose dos Campos, SP (Brazil). Dept. de Energia

1998-07-01

This paper studies the efficiency of a fined tube solar collector used in artificial satellites and the relation of this efficiency with the entropy generation in the fin. The mathematical modeling of heat transfer in the collector leads to a non-linear integrodifferential system of equations, which is solved numerically. The solution gives the efficiency, which is presented as function of geometrical and physical characteristics of the collector. It is also shown that a minimum entropy generation in the fins, in a collector, whose characteristics are subjected to constraints, corresponds to an optimum efficiency, that is, an efficiency value advantageous to collector performance. (author)

Transformation of power generated in railways dispossession belt by solar energy

Directory of Open Access Journals (Sweden)

Ю. П. Гончаров

2015-11-01

Full Text Available The arising deficiency of traditional energy sources necessitates the use of renewable energetics. One of the advantages of the sources of renewable energy is the possibility of constructing a system of distributed generation. For conditions of Ukraine distributed generators placed along the existing facilities with a linear arrangement are the most promising. The railways with their land dispossession belt can be used for these purposes. The distributed generation systems in railway transport can also be used in the regions with an unstable electricity supply, improving power quality, feeding autonomous objects of railway infrastructure. Distributed generation equipment can be used to reduce bias and voltage unbalance in power systems of stationary consumers. The projects using solar energy for the needs of railway transport show their high adaptability and efficiency. The article is devoted to the development of the DC power supply system. The railway contains additional longitudinal DC line with an operating voltage of about 1 kV and a system of semiconductor converters for connecting the longitudinal line and the main contact system through matching modules. Sequential positioning of the longitudinal line and the photo module is consistent with their properties as a current source that is proportional to the intensity of solar radiation. Semiconductor converters should be made using the same "a forward" topology, which simplifies the electrical circuit. Amorphous magnetic alloy is the most promising material for the existing isolation transformers in the system. Proper value of the operating frequency of the AC intermediaries is about 1 kHz. Traction power supply system with distributed PV generation, discussed in this article, will make it possible to put into practice the concept of intellectual traction power supply, optimizing the process of electric energy consumption in the traction network

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.

A Novel Extension Decision-Making Method for Selecting Solar Power Systems

Directory of Open Access Journals (Sweden)

Meng-Hui Wang

2013-01-01

Full Text Available Due to the complex parameters of a solar power system, the designer not only must think about the load demand but also needs to consider the price, weight, and annual power generating capacity (APGC and maximum power of the solar system. It is an important task to find the optimal solar power system with many parameters. Therefore, this paper presents a novel decision-making method based on the extension theory; we call it extension decision-making method (EDMM. Using the EDMM can make it quick to select the optimal solar power system. The paper proposed this method not only to provide a useful estimated tool for the solar system engineers but also to supply the important reference with the installation of solar systems to the consumer.

MULTIFUNCTIONAL SOLAR SYSTEMS FOR HEATING AND COOLING

Directory of Open Access Journals (Sweden)

Doroshenko A.V.

2010-12-01

Full Text Available The basic circuits of multifunctional solar systems of air drainage, heating (hot water supply and heating, cooling and air conditioning are developed on the basis of open absorption cycle with a direct absorbent regeneration. Basic decisions for new generation of gas-liquid solar collectors are developed. Heat-mass-transfer apparatus included in evaporative cooling system, are based on film interaction of flows of gas and liquid and in them, for the creation of nozzle, multi-channel structures from polymeric materials and porous ceramics are used. Preliminary analysis of multifunctional systems possibilities is implemented.

Solar system astrophysics planetary atmospheres and the outer solar system

CERN Document Server

Milone, Eugene F

2014-01-01

The second edition of Solar System Astrophysics: Planetary Atmospheres and the Outer Solar System provides a timely update of our knowledge of planetary atmospheres and the bodies of the outer solar system and their analogs in other planetary systems. This volume begins with an expanded treatment of the physics, chemistry, and meteorology of the atmospheres of the Earth, Venus, and Mars, moving on to their magnetospheres and then to a full discussion of the gas and ice giants and their properties. From here, attention switches to the small bodies of the solar system, beginning with the natural satellites. Then comets, meteors, meteorites, and asteroids are discussed in order, and the volume concludes with the origin and evolution of our solar system. Finally, a fully revised section on extrasolar planetary systems puts the development of our system in a wider and increasingly well understood galactic context. All of the material is presented within a framework of historical importance. This book and its sist...

Application of Power Systems Economics to Wind and Solar Power Integration

OpenAIRE

Mills, Andrew David

2015-01-01

The focus of this dissertation is the economic implications of the technical challenges of integrating variable generation, namely wind and solar, into the electric power system. The research is organized around three topics: short-term variability of wind and solar generation, changes in the economic value of wind and solar with increasing penetration, and the effectiveness of different measures at mitigating changes in economic value with increasing penetration levels. Early studies of PV g...

Theoretical and experimental analysis of a solar thermoelectric power generation device based on gravity-assisted heat pipes and solar irradiation

International Nuclear Information System (INIS)

Zhang, Zhe; Li, Wenbin; Kan, Jiangming; Xu, Daochun

2016-01-01

Highlights: • A technical solution to the power supply of wireless sensor networks is presented. • The low voltage produced by device is boosted from around 1 V to more than 4 V. • An output current and voltage of the device is acquired as 343 mA and 1057 mV. • The device provides output power 362.56 mW in no electricity conditions. • The economic value of device is demonstrated. - Abstract: Solar thermoelectric power generation has been widely used to solve the power supply limitation issue for low-power wireless sensors because of its light weight, high reliability, low cost, lack of noise, and environmental friendliness. A solar thermoelectric power generation system based on gravity-assisted heat pipes and solar radiation is devised in this paper, and its behavior is continuously measured in realistic outdoor circumstances. The effects of key parameters, including solar luminous flux, load resistance, a proportional coefficient, and a relative Seebeck coefficient, are analyzed. Related experimental results show that the device can output a voltage of 1057 mV and an electrical current of 343 mA, resulting in an output power of 362.56 mW. With a stable external energy conversion module under aluminous flux of 7.81 × 10"4 lx, the voltage converted from the nature solar radiation is boosted from 1057 mV to 4.40 V, which meets the rated operating voltage of low power consumption components, such as low-power wireless sensors and ZigBee modules. An economic analysis of the system shows that the solar thermoelectric power generation device is both economically and technically competitive when it is applied in a low-voltage wireless sensor network.

Dual-Axis Solar Tracking System for Maximum Power Production in PV Systems

Directory of Open Access Journals (Sweden)

Muhd.Ikram Mohd. Rashid

2015-12-01

Full Text Available The power developed in a solar energy system depends fundamentally upon the amount of sunlight captured by the photovoltaic modules/arrays. This paper describes a simple electro-mechanical dual axis solar tracking system designed and developed in a study. The control of the two axes was achieved by the pulses generated from the data acquisition (DAQ card fed into four relays. This approach was so chosen to effectively avoid the error that usually arises in sensor-based methods. The programming of the mathematical models of the solar elevation and azimuth angles was done using Borland C++ Builder. The performance and accuracy of the developed system was evaluated with a PV panel at latitude 3.53o N and longitude 103.5o W in Malaysia. The results obtained reflect the effectiveness of the developed tracking system in terms of the energy yield when compared with that generated from a fixed panel. Overall, 20%, 23% and 21% additional energy were produced for the months of March, April and May respectively using the tracker developed in this study.

Solar system plasma waves

Science.gov (United States)

Gurnett, Donald A.

1995-01-01

An overview is given of spacecraft observations of plasma waves in the solar system. In situ measurements of plasma phenomena have now been obtained at all of the planets except Mercury and Pluto, and in the interplanetary medium at heliocentric radial distances ranging from 0.29 to 58 AU. To illustrate the range of phenomena involved, we discuss plasma waves in three regions of physical interest: (1) planetary radiation belts, (2) planetary auroral acceleration regions and (3) the solar wind. In each region we describe examples of plasma waves that are of some importance, either due to the role they play in determining the physical properties of the plasma, or to the unique mechanism involved in their generation.

Recent advancements in plasmon-enhanced promising third-generation solar cells

Directory of Open Access Journals (Sweden)

Thrithamarassery Gangadharan Deepak

2016-08-01

Full Text Available The unique optical properties possessed by plasmonic noble metal nanostructures in consequence of localized surface plasmon resonance (LSPR are useful in diverse applications like photovoltaics, sensing, non-linear optics, hydrogen generation, and photocatalytic pollutant degradation. The incorporation of plasmonic metal nanostructures into solar cells provides enhancement in light absorption and scattering cross-section (via LSPR, tunability of light absorption profile especially in the visible region of the solar spectrum, and more efficient charge carrier separation, hence maximizing the photovoltaic efficiency. This review discusses about the recent development of different plasmonic metal nanostructures, mainly based on Au or Ag, and their applications in promising third-generation solar cells such as dye-sensitized solar cells, quantum dot-based solar cells, and perovskite solar cells.

Fort Huachuca to Benefit from New Solar Technology: Dish-Stirling System Couples Solar Power with Engine to Generate Electricity

National Research Council Canada - National Science Library

1995-01-01

... in partnership with industry. A prototype dish-Stirling solar system, which consists of a large dish of solar concentrators and a Stirling heat engine, will be installed at Fort Huachuca in July and should be in operation about two weeks later...

A novel solar energy integrated low-rank coal fired power generation using coal pre-drying and an absorption heat pump

International Nuclear Information System (INIS)

Xu, Cheng; Bai, Pu; Xin, Tuantuan; Hu, Yue; Xu, Gang; Yang, Yongping

2017-01-01

Highlights: •An improved solar energy integrated LRC fired power generation is proposed. •High efficient and economic feasible solar energy conversion is achieved. •Cold-end losses of the boiler and condenser are reduced. •The energy and exergy efficiencies of the overall system are improved. -- Abstract: A novel solar energy integrated low-rank coal (LRC) fired power generation using coal pre-drying and an absorption heat pump (AHP) was proposed. The proposed integrated system efficiently utilizes the solar energy collected from the parabolic trough to drive the AHP to absorb the low-grade waste heat of the steam cycle, achieving larger amount of heat with suitable temperature for coal’s moisture removal prior to the furnace. Through employing the proposed system, the solar energy could be partially converted into the high-grade coal’s heating value and the cold-end losses of the boiler and the steam cycle could be reduced simultaneously, leading to a high-efficient solar energy conversion together with a preferable overall thermal efficiency of the power generation. The results of the detailed thermodynamic and economic analyses showed that, using the proposed integrated concept in a typical 600 MW LRC-fired power plant could reduce the raw coal consumption by 4.6 kg/s with overall energy and exergy efficiencies improvement of 1.2 and 1.8 percentage points, respectively, as 73.0 MW th solar thermal energy was introduced. The cost of the solar generated electric power could be as low as $0.044/kW h. This work provides an improved concept to further advance the solar energy conversion and utilisation in solar-hybrid coal-fired power generation.

Estimating capacity of solar thermoelectric generator (STEG) panels

International Nuclear Information System (INIS)

Kokhova, I.I.; Malevskii, Yu.N.; Tsvetkov, A.I.

1979-01-01

Energy characteristics of a solar thermoelectric generator (STEG) panel without solar-flux concentration are considered. The design of such devices is no simple task. Several fully justified assumptions have been introduced in an attempt to obtain a solution convenient for engineering calculations

Harmonic analysis and suppression in hybrid wind & PV solar system

Science.gov (United States)

Gupta, Tripti; Namekar, Swapnil

2018-04-01

The growing demand of electricity has led to produce power through non-conventional source of energy such as solar energy, wind energy, hydro power, energy through biogas and biomass etc. Hybrid system is taken to complement the shortcoming of either sources of energy. The proposed system is grid connected hybrid wind and solar system. A 2.1 MW Doubly fed Induction Generator (DFIG) has been taken for analysis of wind farm whose rotor part is connected to two back-to-back converters. A 250 KW Photovoltaic (PV) array taken to analyze solar farm where inverter is required to convert power from DC to AC since electricity generated through solar PV is in the form of DC. Stability and reliability of the system is very important when the system is grid connected. Harmonics is the major Power quality issue which degrades the quality of power at load side. Harmonics in hybrid system arise through the use of power conversion unit. The other causes of harmonics are fluctuation in wind speed and solar irradiance. The power delivered to grid must be free from harmonics and within the limits specified by Indian grid codes. In proposed work, harmonic analysis of the hybrid system is performed in Electrical Transient Analysis program (ETAP) and single tuned harmonic filter is designed to maintain the utility grid harmonics within limits.

Solar Dynamic Power System Stability Analysis and Control

Science.gov (United States)

Momoh, James A.; Wang, Yanchun

1996-01-01

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

Performance analysis of a solar photovoltaic hybrid system for electricity generation and simultaneous water disinfection of wild bacteria strains

International Nuclear Information System (INIS)

Pichel, N.; Vivar, M.; Fuentes, M.

2016-01-01

Highlights: • A new hybrid solar water disinfection and energy generation system was designed and tested. • SOLWAT comprises a water disinfection reactor and a PV module fully integrated into a single unit. • Natural water with wild strains of E. coli, Enterococcus spp. and C. perfringens were studied. • The water disinfection reactor located above the PV module did not affect the final energy output. • The SOLWAT disinfection results were always higher than conventional PET bottles. - Abstract: A hybrid solar water disinfection and energy generation system for meeting the needs of safe drinking water and electricity was designed and tested in Alcalá de Henares (Spain) under summer climatic conditions to demonstrate the feasibility of the concept. Natural water sources with wild strains of Escherichia coli, total coliforms, Enterococcus spp. and Clostridium perfringens (including spores) were studied. Results showed that SOLWAT disinfection efficiency was higher than conventional PET bottles and that the water disinfection reactor located above the PV module did not affect the total energy output produced by the hybrid system in comparison to the single PV module, achieving the same power losses over the 6 h of sun exposure in relation to their power at standard test conditions (STC).

Fusion, space and solar plasmas as complex systems

International Nuclear Information System (INIS)

Dendy, R O; Chapman, S C; Paczuski, M

2007-01-01

Complex systems science seeks to identify simple universal models that capture the key physics of extended macroscopic systems, whose behaviour is governed by multiple nonlinear coupled processes that operate across a wide range of spatiotemporal scales. In such systems, it is often the case that energy release occurs intermittently, in bursty events, and the phenomenology can exhibit scaling, that is a significant degree of self-similarity. Within plasma physics, such systems include Earth's magnetosphere, the solar corona and toroidal magnetic confinement experiments. Guided by broad understanding of the dominant plasma processes-for example, turbulent transport in tokamaks or reconnection in some space and solar contexts-one may construct minimalist complex systems models that yield relevant global behaviour. Examples considered here include the sandpile approach to tokamaks and the magnetosphere and a multiple loops model for the solar coronal magnetic carpet. Such models can address questions that are inaccessible to analytical treatment and are too demanding for contemporary computational resources; thus they potentially yield new insights, but risk being simplistic. Central to the utility of these models is their capacity to replicate distinctive aspects of observed global phenomenology, often strongly nonlinear, or of event statistics, for which no explanation can be obtained from first principles considerations such as the underlying equations. For example, a sandpile model, which embodies critical-gradient-triggered avalanching transport associated with nearest-neighbour mode coupling and simple boundary conditions (and little else), can be used to generate some of the distinctive observed elements of tokamak confinement phenomenology such as ELMing and edge pedestals. The same sandpile model can also generate distributions of energy-release events whose distinctive statistics resemble those observed in the auroral zone. Similarly, a multiple loops model

Solar Heating in Uppsala : A case study of the solar heating system in the neighbourhood Haubitsen in Uppsala

OpenAIRE

Blomqvist, Emelie; Häger, Klara; Wiborgh, Malin

2012-01-01

The housing corporation Uppsalahem has installed asolar heating system in the neighbourhood Haubitsen,which was renovated in 2011. This report examineshow much energy the solar heating system is expectedto generate and which factors could improve theefficiency. Simulations suggest that the solar heatingsystem can to cover about 22 per cent of the domestichot water demand in Haubitsen, which corresponds to50 MWh for a year. If some factors, such as the tilt ofthe solar collectors would have be...

Solar power generation in the US: Too expensive, or a bargain?

International Nuclear Information System (INIS)

Perez, Richard; Zweibel, Ken; Hoff, Thomas E.

2011-01-01

This article identifies the combined value that solar electric power plants deliver to utilities' rate payers and society's tax payers. Benefits that are relevant to utilities and their rate payers include traditional, measures of energy and capacity. Benefits that are tangible to tax payers include environmental, fuel price mitigation, outage risk protection, and long-term economic growth components. Results for the state of New York suggest that solar electric installations deliver between 15 and 40 cents /kWh to ratepayers and tax payers. These results provide economic justification for the existence of payment structures (often referred to as incentives) that transfer value from those who benefit from solar electric generation to those who invest in solar electric generation. - Highlights: → The article presents a valuation of the energy produced by solar generators. → Valuation accounts for physical, socio economic, and environmental attributes. → Value depends upon solar penetration and location and is likely to exceed cost. → The article shows that incentives for solar deployment are justified. → Incentives should be a function of solar energy's site and penetration dependent value.

A performance analysis of solar chimney thermal power systems

Directory of Open Access Journals (Sweden)

Al-Dabbas Awwad Mohammed

2011-01-01

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

Large solar heating system with seasonal storage for buld drying in Lisse, the Netherlands

NARCIS (Netherlands)

Bokhoven, T.P.; Geus, A.C. de

1996-01-01

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

Optimum selection of solar collectors for a solar-driven ejector air conditioning system by experimental and simulation study

International Nuclear Information System (INIS)

Zhang Wei; Ma Xiaoli; Omer, S.A.; Riffat, S.B.

2012-01-01

Highlights: ► Three solar collectors have been compared to drive ejector air conditioning system. ► A simulation program was constructed to study the effect parameters. ► The outdoor test were conducted to validate the solar collector modeling. ► Simulation program was found to predict solar collector performance accurately. ► The optimal design of solar collector system was carried out. - Abstract: In this paper, three different solar collectors are selected to drive the solar ejector air conditioning system for Mediterranean climate. The performance of the three selected solar collector are evaluated by computer simulation and lab test. Computer model is incorporated with a set of heat balance equations being able to analyze heat transfer process occurring in separate regions of the collector. It is found simulation and test has a good agreement. By the analysis of the computer simulation and test result, the solar ejector cooling system using the evacuated tube collector with selective surface and high performance heat pipe can be most economical when operated at the optimum generating temperature of the ejector cooling machine.

Multifunctional Solar Systems Based On Two-Stage Regeneration Absorbent Solution

Directory of Open Access Journals (Sweden)

Doroshenko A.V.

2015-04-01

Full Text Available The concepts of multifunctional dehumidification solar systems, heat supply, cooling, and air conditioning based on the open absorption cycle with direct absorbent regeneration developed. The solar systems based on preliminary drainage of current of air and subsequent evaporated cooling. The solar system using evaporative coolers both types (direct and indirect. The principle of two-stage regeneration of absorbent used in the solar systems, it used as the basis of liquid and gas-liquid solar collectors. The main principle solutions are designed for the new generation of gas-liquid solar collectors. Analysis of the heat losses in the gas-liquid solar collectors, due to the mechanism of convection and radiation is made. Optimal cost of gas and liquid, as well as the basic dimensions and configuration of the working channel of the solar collector identified. Heat and mass transfer devices, belonging to the evaporative cooling system based on the interaction between the film and the gas stream and the liquid therein. Multichannel structure of the polymeric materials used to create the tip. Evaporative coolers of water and air both types (direct and indirect are used in the cooling of the solar systems. Preliminary analysis of the possibilities of multifunctional solar absorption systems made reference to problems of cooling media and air conditioning on the basis of experimental data the authors. Designed solar systems feature low power consumption and environmental friendliness.

Macroporous Double-Network Hydrogel for High-Efficiency Solar Steam Generation Under 1 sun Illumination.

Science.gov (United States)

Yin, Xiangyu; Zhang, Yue; Guo, Qiuquan; Cai, Xiaobing; Xiao, Junfeng; Ding, Zhifeng; Yang, Jun

2018-04-04

Solar steam generation is one of the most promising solar-energy-harvesting technologies to address the issue of water shortage. Despite intensive efforts to develop high-efficiency solar steam generation devices, challenges remain in terms of the relatively low solar thermal efficiency, complicated fabrications, high cost, and difficulty in scaling up. Herein, a double-network hydrogel with a porous structure (p-PEGDA-PANi) is demonstrated for the first time as a flexible, recyclable, and efficient photothermal platform for low-cost and scalable solar steam generation. As a novel photothermal platform, the p-PEGDA-PANi involves all necessary properties of efficient broadband solar absorption, exceptional hydrophilicity, low heat conductivity, and porous structure for high-efficiency solar steam generation. As a result, the hydrogel-based solar steam generator exhibits a maximum solar thermal efficiency of 91.5% with an evaporation rate of 1.40 kg m -2 h -1 under 1 sun illumination, which is comparable to state-of-the-art solar steam generation devices. Furthermore, the good durability and environmental stability of the p-PEGDA-PANi hydrogel enables a convenient recycling and reusing process toward real-life applications. The present research not only provides a novel photothermal platform for solar energy harvest but also opens a new avenue for the application of the hydrogel materials in solar steam generation.

Solar tracking system

Science.gov (United States)

Okandan, Murat; Nielson, Gregory N.

2016-07-12

Solar tracking systems, as well as methods of using such solar tracking systems, are disclosed. More particularly, embodiments of the solar tracking systems include lateral supports horizontally positioned between uprights to support photovoltaic modules. The lateral supports may be raised and lowered along the uprights or translated to cause the photovoltaic modules to track the moving sun.

Solar photovoltaic (PV) energy; latest developments in the building integrated and hybrid PV systems

International Nuclear Information System (INIS)

Zahedi, A.

2006-01-01

Environmental concerns are growing and interest in environmental issues is increasing and the idea of generating electricity with less pollution is becoming more and more attractive. Unlike conventional generation systems, fuel of the solar photovoltaic energy is available at no cost. And solar photovoltaic energy systems generate electricity pollution-free and can easily be installed on the roof of residential as well as on the wall of commercial buildings as grid-connected PV application. In addition to grid-connected rooftop PV systems, solar photovoltaic energy offers a solution for supplying electricity to remote located communities and facilities, those not accessible by electricity companies. The interest in solar photovoltaic energy is growing worldwide. Today, more than 3500MW of photovoltaic systems have been installed all over the world. Since 1970, the PV price has continuously dropped [8]. This price drop has encouraged worldwide application of small-scale residential PV systems. These recent developments have led researchers concerned with the environment to undertake extensive research projects for harnessing renewable energy sources including solar energy. The usage of solar photovoltaic as a source of energy is considered more seriously making future of this technology looks promising. The objective of this contribution is to present the latest developments in the area of solar photovoltaic energy systems. A further objective of this contribution is to discuss the long-term prospect of the solar photovoltaic energy as a sustainable energy supply. [Author

Solar System Evolution through Planetesmial Collisions

Science.gov (United States)

Trierweiler, Isabella; Laughlin, Greg

2018-01-01

Understanding planet formation is crucial to unraveling the history of our Solar System. Refining our theory of planet formation has become particularly important as the discovery of exoplanet systems through missions like Kepler have indicated that our system is incredibly unique. Compared to other systems around Sun-like stars, we are missing a significant amount of mass in the inner region of our solar system.A leading explanation for the low mass of the terrestrial planets is Jupiter’s Grand Tack. In this theory, the existence of the rocky planets is thought to be the result of the migration of Jupiter through the inner solar system. This migration could spark a collisional cascade of planetesimals, allowing planetesimals to drift inwards and shepherd an original set of massive planets into the Sun, thus explaining the absence of massive planets in our current system. The remnants of the planetesimals would them become the building blocks for a new generation of smaller, rocky planets.Using the N-body simulator REBOUND, we investigate the dynamics of the Grand Tack. We focus in particular on collisional cascades, which are thought to cause the inward planetesimal drift. We first modify the simulator to account for fragmentation outcomes in planetesimal collisions. Modeling disks of varying initial conditions, we then characterize the disk conditions needed to begin a cascade and shed light on the solar system’s dynamics just prior to the formation of the terrestrial planets.

Solar Water Heating System for Biodiesel Production

Directory of Open Access Journals (Sweden)

Syaifurrahman

2018-01-01

Full Text Available Nowadays, electricity become very expensive thing in some remote areas. Energy from solar panels give the solution as renewable energy that is environment friendly. West Borneo is located on the equator where the sun shines for almost 10-15 hours/day. Solar water heating system which is includes storage tank and solar collections becomes a cost-effective way to generate the energy. Solar panel heat water is delivered to water in storage tank. Hot water is used as hot fluid in biodiesel jacked reactor. The purposes of this research are to design Solar Water Heating System for Biodiesel Production and measure the rate of heat-transfer water in storage tank. This test has done for 6 days, every day from 8.30 am until 2.30 pm. Storage tank and collection are made from stainless steel and polystyrene a well-insulated. The results show that the heater can be reach at 50ºC for ±2.5 hours and the maximum temperature is 62ºC where the average of light intensity is 1280 lux.

Solar Water Heating System for Biodiesel Production

Science.gov (United States)

Syaifurrahman; Usman, A. Gani; Rinjani, Rakasiwi

2018-02-01

Nowadays, electricity become very expensive thing in some remote areas. Energy from solar panels give the solution as renewable energy that is environment friendly. West Borneo is located on the equator where the sun shines for almost 10-15 hours/day. Solar water heating system which is includes storage tank and solar collections becomes a cost-effective way to generate the energy. Solar panel heat water is delivered to water in storage tank. Hot water is used as hot fluid in biodiesel jacked reactor. The purposes of this research are to design Solar Water Heating System for Biodiesel Production and measure the rate of heat-transfer water in storage tank. This test has done for 6 days, every day from 8.30 am until 2.30 pm. Storage tank and collection are made from stainless steel and polystyrene a well-insulated. The results show that the heater can be reach at 50ºC for ±2.5 hours and the maximum temperature is 62ºC where the average of light intensity is 1280 lux.

ADielectric Multilayer Filter for Combining Photovoltaics with a Stirling Engine for Improvement of the Efficiency of Solar Electricity Generation

Institute of Scientific and Technical Information of China (English)

寿春晖; 骆仲泱; 王涛; 沈伟东; ROSENGARTEN Gary; 王诚; 倪明江; 岑可法

2011-01-01

In this Letter we outline a dielectric multilayer spectrally selective filter designed for solar energy applications. The optical performance of this 78-layer interference filter constructed by TiOx and SiO2 is presented. A hybrid system combining photovoltaic cells with a solar-powered Stirling engine using the designed filter is analyzed. The calculated results show the advantages of this spectrally selective method for solar power generation.%In this Letter we outline a dielectric multilayer spectrally selective filter designed for solar energy applications.The optical performance of this 78-layer interference filter constructed by TiOx and SiO2 is presented.A hybrid system combining photovoltaic cells with a solar-powered Stirling engine using the designed filter is analyzed.The calculated results show the advantages of this spectrally selective method for solar power generation.

Design of photovoltaic array electrical system based on solar power generation%基于太阳能发电的光伏阵列电气系统设计

Institute of Scientific and Technical Information of China (English)

窦伟山; 王薇

2017-01-01

清洁能源的使用是未来社会发展的趋势.以光伏发电为研究模型,对实现太阳能的高效利用展开研究,提出了一种高效的光伏阵列,使太阳能发电系统的能源利用率得到了显著的提升.通过对太阳能发电的电气系统进行一次设计,提出了35 kV侧无功补偿装置,使得系统更加合理、有效.%The use of clean energy is the future trend of social development.Using the solar photovoltaic power generation as the research model,the efficient utilization of solar energy was researched.A kind of high efficient photovoltaic array was put forward,significantly improving the energy efficiency of solar power generation system.Through the design of solar power generation electrical system,the 35 kV side reactive power compensation device was put forward,making the system more reasonable and effective.

Solar central receiver reformer system for ammonia plants

Science.gov (United States)

1980-07-01

Details of the conceptual design, economic analysis, and development plan for a solar central receiver system for retrofitting the Valley Nitrogen Producers, Inc., El Centro, California 600 ST/SD Ammonia Plant are presented. The retrofit system consists of a solar central receiver reformer (SCRR) operating in parallel with the existing fossil fired reformer. Steam and hydrocarbon react in the catalyst filled tubes of the inner cavity receiver to form a hydrogen rich mixture which is the syngas feed for the ammonia production. The SCRR system displaces natural gas presently used in the fossil reformer combustion chamber. The solar reformer retrofit system characteristics and its interface with the existing plant are simple, incorporating state of the art components with proven technology. A northfield composed of one thousand forty second generation heliostats provides solar energy to the receiver which is positioned on top of a 90 meter high steel tower. The overall economics of this system can provide over 20% discount cash flow rate of return with proper investment and market conditions.

Experimental study of a combined system of solar Kang and solar air collector

International Nuclear Information System (INIS)

Wei, Wei; Ji, Jie; Chow, Tin-Tai; He, Wei; Chen, Haifei; Guo, Chao; Yu, Hancheng

2015-01-01

Highlights: • A combined system of solar Kang and solar air collector is proposed. • An experimental study on the combined system is made. • The mean air temperature reaches 18.5 °C and maintains above 18 °C for 13 h. • The corresponding mean indoor air temperature of the reference room is 8.9 °C. • The Kang surface temperature reaches 27 °C and maintains above 18 °C for 23 h. - Abstract: Chinese Kang is widely used as heated bed and for heat recovery of cooking stove in Northern China. However there are main drawbacks of indoor and outdoor air pollutant generation and heavy demands on solid fuel handling. A novel combined Kang system, which integrates solar Kang and solar air collector, is here proposed. Experiments were conducted to examine the alternative operating modes: (i) only solar air collector in service, (ii) only solar Kang in service, and (iii) both solar Kang and solar air collector in service. The results show that these three modes behave differently and have distinct effects on room thermal environment in winter. When this pollution-free system operates under the third combined mode, the room temperature increases significantly and the vertical temperature gradient reduces. The Kang surface temperature increases and its uniformity is improved. It is also found that the room air temperature is closely related to the Kang surface temperature. Furthermore, most of the time the thermal environment meets the occupant need. This paper reports the experimental work and investigates into the effects on indoor thermal environment as in rural residences in Northern China

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

Science.gov (United States)

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

1983-01-01

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

Solar combi systems

DEFF Research Database (Denmark)

Andersen, Elsa

2007-01-01

The focus in the present Ph.D. thesis is on the active use of solar energy for domestic hot water and space heating in so-called solar combi systems. Most efforts have been put into detailed investigations on the design of solar combi systems and on devices used for building up thermal...... the thermal behaviour of different components, and the theoretical investigations are used to study the influence of the thermal behaviour on the yearly thermal performance of solar combi systems. The experimental investigations imply detailed temperature measurements and flow visualization with the Particle...... Image Velocimetry measurement method. The theoretical investigations are based on the transient simulation program TrnSys and Computational Fluid Dynamics. The Ph.D. thesis demonstrates the influence on the thermal performance of solar combi systems of a number of different parameters...

Comparison of sensorless dimming control based on building modeling and solar power generation

International Nuclear Information System (INIS)

Lee, Naeun; Kim, Jonghun; Jang, Cheolyong; Sung, Yoondong; Jeong, Hakgeun

2015-01-01

Artificial lighting in office buildings accounts for about 30% of the total building energy consumption. Lighting energy is important to reduce building energy consumption since artificial lighting typically has a relatively large energy conversion factor. Therefore, previous studies have proposed a dimming control using daylight. When applied dimming control, method based on building modeling does not need illuminance sensors. Thus, it can be applied to existing buildings that do not have illuminance sensors. However, this method does not accurately reflect real-time weather conditions. On the other hand, solar power generation from a PV (photovoltaic) panel reflects real-time weather conditions. The PV panel as the sensor improves the accuracy of dimming control by reflecting disturbance. Therefore, we compared and analyzed two types of sensorless dimming controls: those based on the building modeling and those that based on solar power generation using PV panels. In terms of energy savings, we found that a dimming control based on building modeling is more effective than that based on solar power generation by about 6%. However, dimming control based on solar power generation minimizes the inconvenience to occupants and can also react to changes in solar radiation entering the building caused by dirty window. - Highlights: • We conducted sensorless dimming control based on solar power generation. • Dimming controls using building modeling and solar power generation were compared. • The real time weather conditions can be considered by using solar power generation. • Dimming control using solar power generation minimizes inconvenience to occupants

Quality charter. Instrumentation of solar and wind powered electricity generating systems in isolated sites. A preliminary functional analysis; Charte de qualite. Instrumentation des systemes de production d`electricite en sites isoles a base d`energie photovoltaique et eolienne. Premiere analyse fonctionnelle

Energy Technology Data Exchange (ETDEWEB)

Schmitt, A.; Mauras, P.; Jacquin, P.

1996-10-01

This document is intended to become one of the Quality Charter documents. It presents the functions which must be provided by the instrumentation systems designed for use in solar and wind powered electricity generating systems in isolated designed for use in solar and wind powered electricity generating systems in isolated sites and should be viewed in close conjunction with the `Typology` and `Energy Management` documents covering the same systems of electricity generation in isolated sites; Together, these documents provide the definition of a range of eight energy management systems and four instrumentation systems specially adapted to the different types of facilities and requirements. (authors)

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

Science.gov (United States)

Wilcox, Brian H.

2012-01-01

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

Solar energy conversion systems

CERN Document Server

Brownson, Jeffrey R S

2013-01-01

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

Sizing an isolated wind-solar-fuel cell generation system based on the particle swarm optimization method; Dimensionamiento de un sistema de generacion aislado eolico-solar-celda de combustible basado en el metodo de optimizacion de enjambre de particulas

Energy Technology Data Exchange (ETDEWEB)

Sanchez-Huerta, V; Ramirez-Arredondo, Juan M. [Universidad de Quintana Roo, Chetumal, Quintana Roo (Mexico)]. E-mail: vsanchez@gdl.cinvestav.mx; Arriaga-Hurtado, L. G. [CIDETEQ, Queretaro (Mexico)

2009-09-15

Sizing an electric energy system requires an analysis of investment, maintenance and operating costs. In the case of a generation system that uses renewable sources, optimal capacity becomes more complex compared to a conventional system, because of the randomness of renewable resources (wind, solar) and the still high costs of wind and photovoltage generator modules. This work presents the optimal sizing of a wind-solar-fuel cell generation system, minimizing the costs of the system while satisfying the energy demands of an isolated charge. The optimization method used is based on an evolutionary programming technique known as particle swarms (PSO-particle swarm optimization). The generation of energy with a hybrid system is discussed, based on the profile of insolation and wind availability at the site, with the objective of satisfying a specific electric demand. [Spanish] El dimensionamiento de un sistema de generacion de energia electrica requiere un analisis de los costos de inversion, mantenimiento y operacion. En el caso de un sistema de generacion que utiliza fuentes renovables la capacidad optima resulta mas compleja con respecto a un sistema convencional, debido a la aleatoriedad de los recursos renovables (eolico, solar), y a los aun altos costos de generadores eolicos y modulos fotovoltaicos. En este trabajo se presenta el dimensionamiento optimo de un sistema de generacion eolico-solar-celda de combustible minimizando los costos del sistema que satisfaga la energia demandada por una carga aislada. El metodo de optimizacion utilizado esta basado en una tecnica de programacion evolutiva conocida como enjambre de particulas (PSO por sus siglas en ingles: particle swarm optimization). Se plantea la generacion de energia del sistema hibrido con base a la insolacion y el perfil del viento disponible en sitio, con objeto de satisfacer una demanda electrica determinada.

SolAir. Innovative solar collectors for efficient and cost-effective solar thermal power generation - Final report

Energy Technology Data Exchange (ETDEWEB)

Barbato, M. C.; Haueter, Ph.; Bader, R.; Steinfeld, A.; Pedretti, A.

2008-12-15

This report presents the main results of the project. The project has been started at the end of 2007 and has been successfully finished in December 2008. The present project of ALE AirLight Energy aims at the engineering investigation and design of a novel concept of a solar collector system for efficient and cost-effective solar thermal power generation. The technology exploits an air-inflated reflective structure to concentrate solar radiation. This new arrangement reduces investment costs of the collector field and promises to be economically competitive. A first prototype, built in 2007, has been redesigned and heavily modified during this project. In the new configuration, by using secondary mirrors, the focal area is located close to the main structure and allows the integration of the receiver into the inflated structure. The topics developed in this document are as follows: (i) Design solutions for the concentrated energy receiver suitable for the revised SolAir concentrator concept. (ii) Solar flux simulation via Monte Carlo method. (iii) New version of the ALE AirLight Energy concentrator prototype. (iv) Prototype radiative flux measurements. (author)

Solar system astrophysics background science and the inner solar system

CERN Document Server

Milone, Eugene F

2008-01-01

Solar System Astrophysics: A Text for the Science of Planetary Systems covers the field of solar system astrophysics beginning with basic tools of spherical astronomy, coordinate frames, and celestial mechanics. Historical introductions precede the development and discussion in most chapters. After a basic treatment of the two- and restricted three-body system motions in Background Science and the Inner Solar System, perturbations are discussed, followed by the Earth's gravitational potential field and its effect on satellite orbits. This is followed by analysis of the Earth-Moon system and the interior planets. In Planetary Atmospheres and the Outer Solar System, the atmospheres chapters include detailed discussions of circulation, applicable also to the subsequent discussion of the gas giants. The giant planets are discussed together, and the thermal excesses of three of them are highlighted. This is followed by chapters on moons and rings, mainly in the context of dynamical stability, comets and meteors, m...

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

Energy Technology Data Exchange (ETDEWEB)

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

2012-06-01

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

Automated positioning dual-axis solar tracking system with precision elevation and azimuth angle control

International Nuclear Information System (INIS)

Sidek, M.H.M.; Azis, N.; Hasan, W.Z.W.; Ab Kadir, M.Z.A.; Shafie, S.; Radzi, M.A.M.

2017-01-01

This paper presents a study on an automated positioning open-loop dual-axis solar tracking system. The solar tracker was designed and fabricated using standard cylindrical aluminium hollow and Polyuthrene (PE). The control system of the solar tracker was governed by Micro Controller Unit (MCU) with auxiliary devices which includes encoder and Global Positioning System (GPS). The sun path trajectory algorithm utilizing the astronomical equation and GPS information was also embedded in the system. The power generation performance of the dual-axis solar tracking system was compared with the fixed-tilted Photovoltaic (PV) system. It is found that the solar tracker is able to position itself automatically based on sun path trajectory algorithm with an accuracy of ±0.5°. The embedded Proportional Integral Derivative (PID) positioning system improves the tracking of elevation and azimuth angles with minimum energy consumption. It is reveals that the proposed solar tracker is able generate 26.9% and 12.8% higher power than fixed-tilted PV system on a clear and heavy overcast conditions respectively. Overall, the open-loop dual-axis solar tracker can be deployed automatically at any location on the earth with minimal configurations and is suitable for mobile solar tracking system. - Highlights: • Self-positioning dual-axis solar tracking system. • Precise control of elevation and azimuth angle. • Sun path trajectory based on astronomical equation and GPS. • Can achieve up to 26.9% higher power than fixed-tilted PV system under clear weather condition.

Commercially Available Activated Carbon Fiber Felt Enables Efficient Solar Steam Generation.

Science.gov (United States)

Li, Haoran; He, Yurong; Hu, Yanwei; Wang, Xinzhi

2018-03-21

Sun-driven steam generation is now possible and has the potential to help meet future energy needs. Current technologies often use solar condensers to increase solar irradiance. More recently, a technology for solar steam generation that uses heated surface water and low optical concentration is reported. In this work, a commercially available activated carbon fiber felt is used to generate steam efficiently under one sun illumination. The evaporation rate and solar conversion efficiency reach 1.22 kg m -2 h -1 and 79.4%, respectively. The local temperature of the evaporator with a floating activated carbon fiber felt reaches 48 °C. Apart from the high absorptivity (about 94%) of the material, the evaporation performance is enhanced thanks to the well-developed pores for improved water supply and steam escape and the low thermal conductivity, which enables reduced bulk water temperature increase. This study helps to find a promising material for solar steam generation using a water evaporator that can be produced economically (∼6 $/m 2 ) with long-term stability.

A hybrid reconfigurable solar and wind energy system

Science.gov (United States)

Gadkari, Sagar A.

We study the feasibility of a novel hybrid solar-wind hybrid system that shares most of its infrastructure and components. During periods of clear sunny days the system will generate electricity from the sun using a parabolic concentrator. The concentrator is formed by individual mirror elements and focuses the light onto high intensity vertical multi-junction (VMJ) cells. During periods of high wind speeds and at night, the same concentrator setup will be reconfigured to channel the wind into a wind turbine which will be used to harness wind energy. In this study we report on the feasibility of this type of solar/wind hybrid energy system. The key mechanisms; optics, cooling mechanism of VMJ cells and air flow through the system were investigated using simulation tools. The results from these simulations, along with a simple economic analysis giving the levelized cost of energy for such a system are presented. An iterative method of design refinement based on the simulation results was used to work towards a prototype design. The levelized cost of the system achieved in the economic analysis shows the system to be a good alternative for a grid isolated site and could be used as a standalone system in regions of lower demand. The new approach to solar wind hybrid system reported herein will pave way for newer generation of hybrid systems that share common infrastructure in addition to the storage and distribution of energy.

Economic analysis of power generation from floating solar chimney power plant

International Nuclear Information System (INIS)

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

2009-01-01

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

Evaluation of Glare at the Ivanpah Solar Electric Generating System

Energy Technology Data Exchange (ETDEWEB)

Ho, Clifford K. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sims, Cianan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Christian, Joshua Mark [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2014-07-01

The Ivanpah Solar Electric Generating System (ISEGS), located on I - 15 about 40 miles (60 km) south of Las Vegas, NV, consists of three power towers 459 ft (140 m) tall and over 170,000 reflective heliostats with a rated capacity of 390 MW. Reports of glare from the plant have been submitted by pilots and air traffic controllers and recorded by the Aviation Safety Reporting System and the California Energy Commission since 2013. Aerial and ground - based surveys of the glare were conducted in April, 2014, to identify the cause and to quantify the irradiance and potential ocular impact s of the glare . Results showed that the intense glare viewed from the airspace above ISEGS was caused by he liostats in standby mode that were aimed to the side of the receiver. Evaluation of the glare showed that the retinal irradiance and subtended source angle of the glare from the heliostats in standby were sufficient to cause significant ocular impact (pot ential for after - image) up to a distance of %7E6 miles (10 km), but the values were below the threshold for permanent eye damage . Glare from the receivers had a low potential for after - image at all ground - based monitoring locations outside of the site bound aries. A Letter to Airmen has been issued by the Federal Aviation Administration to notify pilots of the potential glare hazards. Additional measures to mitigate the potential impacts of glare from ISGES are also presented and discussed. This page intentionally left blank

Development of a controller based on Fuzzy theory to better use the energy of a hybrid system power generation solar-photovoltaic and wind; Desenvolvimento de um controlador baseado na teoria Fuzzy para melhor aproveitamento da energia de um sistema hibrido de geracao de energia solar-fotovoltaico e eolico

Energy Technology Data Exchange (ETDEWEB)

Caneppele, Fernando de Lima [Universidade Estadual Paulista (UNESP), Itapeva, SP (Brazil). Campus Experimental], E-mail: fernando@itapeva.unesp.br; Seraphim, Odivaldo Jose [Universidade Estadual Paulista (FCA/UNESP), Botucatu, SP (Brazil). Fac. de Ciencias Agronomicas. Dept. de Engenharia Rural; Gabriel Filho, Luis Roberto de Almeida [Universidade Estadual Paulista (UNESP), Tupa, SP (Brazil). Campus Experimental

2010-07-01

The work developed a methodology fuzzy and simulated its use in control of a hybrid system of electric power generation, using solar-photovoltaic and wind energy. Using this control system, we get the point of maximum energy generation and transfer all the energy generated from alternative sources, solar-photovoltaic and wind energy to charge and / or batteries. The model uses three input variables, which are: wind (wind speed), sun (solar radiation) and batteries (charge the battery bank). With these variables, the fuzzy system will play, according to the rules to be described, what is the source of power supply system, which will have priority and how the batteries are loaded. For the simulations regarding the use of fuzzy theory to control, we used the scientific computing environment MATLAB. In this environment have been analyzed and simulated all mathematical modeling, rules and other variables described in the fuzzy system. This model can be applied to implement a control system of hybrid power generation, providing the best use of renewable energy, solar and wind, so that we can extract the maximum possible energy of these alternative sources without compromising the environment. (author)

Adiabatic resonant oscillations of solar neutrinos in three generations

International Nuclear Information System (INIS)

Kim, C.W.; Sze, W.K.

1987-01-01

The Mikheyev-Smirnov-Wolfenstein model of resonant solar-neutrino oscillations is discussed for three generations of leptons. Assuming adiabatic transitions, bounds for the μ- and e-neutrinos mass-squared difference Δ/sub 21,0/ are obtained as a function of the e-μ mixing angle theta 1 . The allowed region in the Δ/sub 21,0/-theta 1 plot that would solve the solar-neutrino problem is shown to be substantially larger than that of the two-generation case. In particular, the difference between the two- and three-generation cases becomes significant for theta 1 larger than --20 0

Integrated Simulation Development and Decision Support Tool-Set for Utility Market and Distributed Solar Power Generation Electricore, Inc.

Energy Technology Data Exchange (ETDEWEB)

Daye, Tony [Green Power Labs (GPL), San Diego, CA (United States)

2013-09-30

This project will enable utilities to develop long-term strategic plans that integrate high levels of renewable energy generation, and to better plan power system operations under high renewable penetration. The program developed forecast data streams for decision support and effective integration of centralized and distributed solar power generation in utility operations. This toolset focused on real time simulation of distributed power generation within utility grids with the emphasis on potential applications in day ahead (market) and real time (reliability) utility operations. The project team developed and demonstrated methodologies for quantifying the impact of distributed solar generation on core utility operations, identified protocols for internal data communication requirements, and worked with utility personnel to adapt the new distributed generation (DG) forecasts seamlessly within existing Load and Generation procedures through a sophisticated DMS. This project supported the objectives of the SunShot Initiative and SUNRISE by enabling core utility operations to enhance their simulation capability to analyze and prepare for the impacts of high penetrations of solar on the power grid. The impact of high penetration solar PV on utility operations is not only limited to control centers, but across many core operations. Benefits of an enhanced DMS using state-of-the-art solar forecast data were demonstrated within this project and have had an immediate direct operational cost savings for Energy Marketing for Day Ahead generation commitments, Real Time Operations, Load Forecasting (at an aggregate system level for Day Ahead), Demand Response, Long term Planning (asset management), Distribution Operations, and core ancillary services as required for balancing and reliability. This provided power system operators with the necessary tools and processes to operate the grid in a reliable manner under high renewable penetration.

A Green Energy Application in Energy Management Systems by an Artificial Intelligence-Based Solar Radiation Forecasting Model

Directory of Open Access Journals (Sweden)

Ping-Huan Kuo

2018-04-01

Full Text Available The photovoltaic (PV systems generate green energy from the sunlight without any pollution or noise. The PV systems are simple, convenient to install, and seldom malfunction. Unfortunately, the energy generated by PV systems depends on climatic conditions, location, and system design. The solar radiation forecasting is important to the smooth operation of PV systems. However, solar radiation detected by a pyranometer sensor is strongly nonlinear and highly unstable. The PV energy generation makes a considerable contribution to the smart grids via a large number of relatively small PV systems. In this paper, a high-precision deep convolutional neural network model (SolarNet is proposed to facilitate the solar radiation forecasting. The proposed model is verified by experiments. The experimental results demonstrate that SolarNet outperforms other benchmark models in forecasting accuracy as well as in predicting complex time series with a high degree of volatility and irregularity.

Building integration of concentrating solar systems for heating applications

International Nuclear Information System (INIS)

Tsoutsou, Sapfo; Infante Ferreira, Carlos; Krieg, Jan; Ezzahiri, Mohamed

2014-01-01

A new solar collection system integrated on the façade of a building is investigated for Dutch climate conditions. The solar collection system includes a solar façade, a receiver tube and 10 Fresnel lenses. The Fresnel lenses Fresnel lenses considered were linear, non-imaging, line – focused with a system tracking the position of the sun that ensures vertical incidence of the direct solar radiation on the lenses. For the heating system a double-effect absorption heat pump, which requires high temperature of the heating fluid, was used, working with water and lithium-bromide as refrigerant and solution respectively. The Fresnel lens system is connected with the absorption heat pump through a thermal energy storage tank which accumulates the heat from the Fresnel lens system to provide it to the high pressure generator of the absorption heat pump. - Highlights: • The integration of Fresnel lenses in solar thermal building façades is investigated. • Using building integrated Fresnel lenses, 43% heating energy can be saved. • Energy savings in Mediterranean countries are significantly larger. • The absorption heat pump could make great contribution to energy savings for Dutch climate conditions

Solar system astrophysics background science and the inner solar system

CERN Document Server

Milone, Eugene F

2014-01-01

The second edition of Solar System Astrophysics: Background Science and the Inner Solar System provides new insights into the burgeoning field of planetary astronomy. As in the first edition, this volume begins with a rigorous treatment of coordinate frames, basic positional astronomy, and the celestial mechanics of two and restricted three body system problems. Perturbations are treated in the same way, with clear step-by-step derivations. Then the Earth’s gravitational potential field and the Earth-Moon system are discussed, and the exposition turns to radiation properties with a chapter on the Sun. The exposition of the physical properties of the Moon and the terrestrial planets are greatly expanded, with much new information highlighted on the Moon, Mercury, Venus, and Mars. All of the material is presented within a framework of historical importance. This book and its sister volume, Solar System Astrophysics: Planetary Atmospheres and the Outer Solar System, are pedagogically well written, providing cl...

Present condition and the future of photovoltaic generating systems. Part 5. Future perspective of photovoltaic power systems; Taiyo hikarihatsuden system no genjo to shorai. 5. Taiyo hikarihatsuden system no shorai tenbo

Energy Technology Data Exchange (ETDEWEB)

Horigome, T

1994-12-20

In this paper, as the future perspective of photovoltaic power systems, the establishment of the legal environment for the popularization of the photovoltaic power systems in large amounts and the future prediction of the popularization of power generation are described. Specially the following grand ideas are introduced: building in high seas regeneratable energy transformation plants with solar energy as the main energy, generating combined power of photovoltaic, solar heat, wave and temperature difference of the sea water, biomass, solar-bio power generating without CO2 exhaustion, building hard solar plants to produce electricity, hydrogen, methanol and fresh water from regeneratable energy, and breeding fish, shells and see weed in the sea pasture land under the plants, which are the so called `Energy sea pasture high breed plants (REPO Plan)` and also space power generating i.e. setting up special satellites for solar power generation in synchronous orbits, generating power through solar batteries or solar heat and then transmitting it to the earth through microwave. 12 refs., 4 figs.

DC Linked Hybrid Generation System with an Energy Storage Device including a Photo-Voltaic Generation and a Gas Engine Cogeneration for Residential Houses

Science.gov (United States)

Lung, Chienru; Miyake, Shota; Kakigano, Hiroaki; Miura, Yushi; Ise, Toshifumi; Momose, Toshinari; Hayakawa, Hideki

For the past few years, a hybrid generation system including solar panel and gas cogeneration is being used for residential houses. Solar panels can generate electronic power at daytime; meanwhile, it cannot generate electronic power at night time. But the power consumption of residential houses usually peaks in the evening. The gas engine cogeneration system can generate electronic power without such a restriction, and it also can generate heat power to warm up house or to produce hot water. In this paper, we propose the solar panel and gas engine co-generation hybrid system with an energy storage device that is combined by dc bus. If a black out occurs, the system still can supply electronic power for special house loads. We propose the control scheme for the system which are related with the charging level of the energy storage device, the voltage of the utility grid which can be applied both grid connected and stand alone operation. Finally, we carried out some experiments to demonstrate the system operation and calculation for loss estimation.

Numerical simulation of a Linear Fresnel Reflector Concentrator used as direct generator in a Solar-GAX cycle

Energy Technology Data Exchange (ETDEWEB)

Velazquez, N.; Sauceda, D.; Beltran, R. [Instituto de Ingenieria, Universidad Autonoma de Baja California, Blvd. Benito Juarez y Calle de la Normal s/n, Mexicali, Baja California 21280 (Mexico); Garcia-Valladares, O. [Centro de Investigacion en Energia, Universidad Nacional Autonoma de Mexico, Privada Xochicalco s/n, Temixco, Morelos 62580 (Mexico)

2010-03-15

In this work a methodological analysis to design and evaluate the technical feasibility of use a Linear Fresnel Reflector Concentrator (LFRC) as generator in an advanced absorption refrigeration system (Solar-GAX cycle) has been carried out. For this purpose, a detailed one-dimensional numerical simulation of the thermal and fluid-dynamic behavior of a LFRC that solves, in a segregated manner, four subroutines: (a) fluid flow inside the receptor tube, (b) heat transfer in the receptor tube wall, (c) heat transfer in cover tube wall, and (d) solar thermal analysis in the solar concentrator has been developed. The LFRC numerical model has been validated with experimental data obtained from the technical literature; after that, a parametric study for different configurations of design has been carried out in order to obtain the highest solar concentration with the lowest thermal losses, keeping in mind both specific weather conditions and construction restrictions. The numerical result obtained demonstrates that using a LFRC as a direct generator in a Solar-GAX cycle satisfy not only the quantity and quality of the energy demanded by the advanced cooling system, it also allows to obtain higher global efficiencies of the system due to it can be operated in conditions where the maximum performance of the Solar-GAX cycle is obtained without affecting in any significant way the solar collector efficiency. (author)

Numerical simulation of a Linear Fresnel Reflector Concentrator used as direct generator in a Solar-GAX cycle

International Nuclear Information System (INIS)

Velazquez, N.; Garcia-Valladares, O.; Sauceda, D.; Beltran, R.

2010-01-01

In this work a methodological analysis to design and evaluate the technical feasibility of use a Linear Fresnel Reflector Concentrator (LFRC) as generator in an advanced absorption refrigeration system (Solar-GAX cycle) has been carried out. For this purpose, a detailed one-dimensional numerical simulation of the thermal and fluid-dynamic behavior of a LFRC that solves, in a segregated manner, four subroutines: (a) fluid flow inside the receptor tube, (b) heat transfer in the receptor tube wall, (c) heat transfer in cover tube wall, and (d) solar thermal analysis in the solar concentrator has been developed. The LFRC numerical model has been validated with experimental data obtained from the technical literature; after that, a parametric study for different configurations of design has been carried out in order to obtain the highest solar concentration with the lowest thermal losses, keeping in mind both specific weather conditions and construction restrictions. The numerical result obtained demonstrates that using a LFRC as a direct generator in a Solar-GAX cycle satisfy not only the quantity and quality of the energy demanded by the advanced cooling system, it also allows to obtain higher global efficiencies of the system due to it can be operated in conditions where the maximum performance of the Solar-GAX cycle is obtained without affecting in any significant way the solar collector efficiency.

Experimental System of Solar Adsorption Refrigeration with Concentrated Collector.

Science.gov (United States)

Yuan, Z X; Li, Y X; Du, C X

2017-10-18

To improve the performance of solar adsorption refrigeration, an experimental system with a solar concentration collector was set up and investigated. The main components of the system were the adsorbent bed, the condenser, the evaporator, the cooling sub-system, and the solar collector. In the first step of the experiment, the vapor-saturated bed was heated by the solar radiation under closed conditions, which caused the bed temperature and pressure to increase. When the bed pressure became high enough, the bed was switched to connect to the condenser, thus water vapor flowed continually from the bed to the condenser to be liquefied. Next, the bed needed to cool down after the desorption. In the solar-shielded condition, achieved by aluminum foil, the circulating water loop was opened to the bed. With the water continually circulating in the bed, the stored heat in the bed was took out and the bed pressure decreased accordingly. When the bed pressure dropped below the saturation pressure at the evaporation temperature, the valve to the evaporator was opened. A mass of water vapor rushed into the bed and was adsorbed by the zeolite material. With the massive vaporization of the water in the evaporator, the refrigeration effect was generated finally. The experimental result has revealed that both the COP (coefficient of the performance of the system) and the SCP (specific cooling power of the system) of the SAPO-34 zeolite was greater than that of the ZSM-5 zeolite, no matter whether the adsorption time was longer or shorter. The system of the SAPO-34 zeolite generated a maximum COP of 0.169.

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

Costs comparison between solar photovoltaic system and moto-generator for supplying the isolated small community

International Nuclear Information System (INIS)

Fadigas, E.A.F.A.; Faga, M.T.W.

1993-01-01

This work describes a technical configuration from which making an economic evaluation that comparing the photovoltaic option with moto-generator, energy source very used in rural community, presenting the relations of implantation cost between two options, showing the sensibility of these cost in function of some variables like: demand, reduction tax, solar radiation, and, as the solar energy market photovoltaic presents cost upper than international cost due to the inexpressive scale economy, make the analysis with one prices range, possibility an evaluation not limited to the national market. 3 refs, 8 figs

Will 3552 Don Quixote escape from the Solar System?

Directory of Open Access Journals (Sweden)

Suryadi Siregar

2011-05-01

Full Text Available Asteroid 1983 SA, well known as 3552 Don Quixote, is one of Near Earth Asteroids (NEAs which is the most probable candidate for the cometary origin, or otherwise as Jupiter-Family-Comets (JFCs. The aim of this study is to investigate the possibility of 3552 Don Quixote to be ejected from the Solar System. This paper presents an orbital evolution of 100 hypothetical asteroids generated by cloning 3552 Don Quixote. Investigation of its orbital evolution is conducted by using the SWIFT subroutine package, where the gravitational perturbations of eight major planets in the Solar System are considered. Over very short time scales (220 kyr relative to the Solar System life time (10 Gyr, the asteroid 3552 Don Quixote gave an example of chaotic motion that can cause asteroid to move outward and may be followed by escaping from the Solar System. Probability of ejection within the 220 kyr time scale is 50%.

An integrated solar thermal power system using intercooled gas turbine and Kalina cycle

International Nuclear Information System (INIS)

Peng, Shuo; Hong, Hui; Jin, Hongguang; Wang, Zhifeng

2012-01-01

A new solar tower thermal power system integrating the intercooled gas turbine top cycle and the Kalina bottoming cycle is proposed in the present paper. The thermodynamic performance of the proposed system is investigated, and the irreversibility of energy conversion is disclosed using the energy–utilization diagram method. On the top cycle of the proposed system, the compressed air after being intercooled is heated at 1000 °C or higher at the solar tower receiver and is used to drive the gas turbine to generate power. The ammonia–water mixture as the working substance of the bottom cycle recovers the waste heat from the gas turbine to generate power. A concise analytical formula of solar-to-electric efficiency of the proposed system is developed. As a result, the peak solar-to-electric efficiency of the proposed system is 27.5% at a gas turbine inlet temperature of 1000 °C under the designed solar direct normal irradiance of 800 W/m 2 . Compared with a conventional solar power tower plant, the proposed integrated system conserves approximately 69% of consumed water. The results obtained in the current study provide an approach to improve solar-to-electric efficiency and offer a potential to conserve water for solar thermal power plants in arid area. -- Highlights: ► An Integrated Solar Thermal Power System is modeled. ► A formula forecasting the thermodynamic performance is proposed. ► The irreversibility of energy conversion is disclosed using an energy utilization method. ► The effect of key operational parameters on thermal performance is examined.

Analysis of grid connected solar PV system in the Southeastern Part of Bangladesh

International Nuclear Information System (INIS)

Ariful Islam; Fatema Akther Shima; Akhera Khanam

2013-01-01

Bangladesh is a potential site of implementing renewable energy system to reduce the severe power crisis throughout the year. According to this, Chittagong is the southeastern part of Bangladesh is also a potential site for implementing renewable energy system such as grid-connected photovoltaic (PV) system. Financial viability and green-house gas emission reduction of solar PV as an electricity generation source are assessed for 500 kW grid connected solar PV system at University of Chittagong, Chittagong. Homer simulation soft-ware and monthly average solar radiation data from NASA is used for this task. In the proposed system monthly electricity generation varies between 82.65 MW h and 60.3 MW h throughout the year with a mean value of 68.25 MW h depending on the monthly highest and lowest solar radiation data. It is found that per unit electricity production cost is US$ 0.20 based on project lifetime 25 years. The IRR, equity payback and benefit-cost ratio shows favorable condition for development of the proposed solar PV system in this site. A minimum 664 tones of green-house gas emissions can be reduced annually utilizing the proposed system. (authors)

Lightweight, Mesoporous, and Highly Absorptive All-Nanofiber Aerogel for Efficient Solar Steam Generation.

Science.gov (United States)

Jiang, Feng; Liu, He; Li, Yiju; Kuang, Yudi; Xu, Xu; Chen, Chaoji; Huang, Hao; Jia, Chao; Zhao, Xinpeng; Hitz, Emily; Zhou, Yubing; Yang, Ronggui; Cui, Lifeng; Hu, Liangbing

2018-01-10

The global fresh water shortage has driven enormous endeavors in seawater desalination and wastewater purification; among these, solar steam generation is effective in extracting fresh water by efficient utilization of naturally abundant solar energy. For solar steam generation, the primary focus is to design new materials that are biodegradable, sustainable, of low cost, and have high solar steam generation efficiency. Here, we designed a bilayer aerogel structure employing naturally abundant cellulose nanofibrils (CNFs) as basic building blocks to achieve sustainability and biodegradability as well as employing a carbon nanotube (CNT) layer for efficient solar utilization with over 97.5% of light absorbance from 300 to 1200 nm wavelength. The ultralow density (0.0096 g/cm 3 ) of the aerogel ensures that minimal material is required, reducing the production cost while at the same time satisfying the water transport and thermal-insulation requirements due to its highly porous structure (99.4% porosity). Owing to its rationally designed structure and thermal-regulation performance, the bilayer CNF-CNT aerogel exhibits a high solar-energy conversion efficiency of 76.3% and 1.11 kg m -2 h -1 at 1 kW m -2 (1 Sun) solar irradiation, comparable or even higher than most of the reported solar steam generation devices. Therefore, the all-nanofiber aerogel presents a new route for designing biodegradable, sustainable, and scalable solar steam generation devices with superb performance.

Performance optimization for a variable throat ejector in a solar refrigeration system

KAUST Repository

Yen, R.H.; Huang, B.J.; Chen, C.Y.; Shiu, T.Y.; Cheng, C.W.; Chen, S.S.; Shestopalov, K.

2013-01-01

In a solar vapor ejector refrigeration system, the solar heat supply may vary because of variations in solar irradiation intensity, making it difficult to maintain a steady generator temperature. To improve ejector performance, this study proposes a variable throat ejector (VTEJ) and analyzes its performance using CFD simulations. The following conclusions can be drawn. An ejector with a greater throat area and larger solar collector allows a wider operating range of generator temperatures, but may be overdesigned and expensive. Conversely, decreasing the throat area limits the operating range of generator temperatures. Thus the ejector with a fixed throat area may be unsuitable to use solar energy as a heat source. For a VTEJ, this study derives a curve-fitting relationship between the optimum throat area ratio and the operating temperatures. Using this relationship to adjust the throat area ratio, the ejector can consistently achieve optimal and stable performances under a varying solar heat supply. © 2013 Elsevier Ltd and IIR. All rights reserved.

Performance optimization for a variable throat ejector in a solar refrigeration system

KAUST Repository

Yen, R.H.

2013-08-01

In a solar vapor ejector refrigeration system, the solar heat supply may vary because of variations in solar irradiation intensity, making it difficult to maintain a steady generator temperature. To improve ejector performance, this study proposes a variable throat ejector (VTEJ) and analyzes its performance using CFD simulations. The following conclusions can be drawn. An ejector with a greater throat area and larger solar collector allows a wider operating range of generator temperatures, but may be overdesigned and expensive. Conversely, decreasing the throat area limits the operating range of generator temperatures. Thus the ejector with a fixed throat area may be unsuitable to use solar energy as a heat source. For a VTEJ, this study derives a curve-fitting relationship between the optimum throat area ratio and the operating temperatures. Using this relationship to adjust the throat area ratio, the ejector can consistently achieve optimal and stable performances under a varying solar heat supply. © 2013 Elsevier Ltd and IIR. All rights reserved.

Solar Energy Systems

Science.gov (United States)

1984-01-01

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

Performance analysis of a solar-powered solid state heat engine for electricity generation

International Nuclear Information System (INIS)

Long, Rui; Li, Baode; Liu, Zhichun; Liu, Wei

2015-01-01

A hybrid system consisting of a CPC (compound parabolic collector) system, a SOE (solid oxide electrolyzer) system and a PEMFC (proton exchange membrane fuel cell) system was proposed to harvest solar energy. And a sensitivity analysis was conducted to evaluate the system performance. The impacts of operating temperatures of the SOE and PEMFC system, and the direct irradiation intensity of the sun on the performance characteristics were systematically analyzed. Results revealed that there exists an optimal SOE operating temperature leading to the maximum power output and maximum electrical efficiency simultaneously. Larger operating temperature of the PEMFC resulted in larger power output and higher efficiency. There also existed optimal direct irradiation intensities leading to the maximum power output and maximum electrical efficiency. Furthermore, the performance of the proposed solar energy harvesting system for practical use in real-life was also simulated. This may serve a clean technology for electricity generation. - Highlights: • A hybrid system consisting of CPC, SOE and PEMFC is proposed to harvest solar energy. • A sensitivity analysis was conducted to evaluate the system performance. • Power output and electrical efficiency have maximum values. • Performance of the proposed hybrid system for practical use was simulated.

Hybrid system power generation'wind-photovoltaic' connected to the ...

African Journals Online (AJOL)

Hybrid system power generation'wind-photovoltaic' connected to the ... from Hybrid System, power delivered to or from grid and phase voltage of the inverter leg. ... Renewable Energy, Electrical Network 220 kV, Hybrid System, Solar, MPPT.

Systematic power autonomy. Hybrid solar system makes Christine Schoen independent of oil and gas supply; Energieautark mit System. Eine Hybridsolaranlage macht Christine Schoen unabhaengig von Oel und Gas

Energy Technology Data Exchange (ETDEWEB)

Neumann, Hinrich; Podewils, Christoph

2009-12-15

Hybrid solar systems generate both heat and power; they are still rare because it is difficult to maintain the balance between heat and power generation. However, they have their advantages as is proved by the hybrid solar system of Christine Schoen. On the one hand, she heats her old house; on the other hand, she optimizes solar power generation in her system. (orig.)

Optimised heat recovery steam generators for integrated solar combined cycle plants

Science.gov (United States)

Peterseim, Jürgen H.; Huschka, Karsten

2017-06-01

The cost of concentrating solar power (CSP) plants is decreasing but, due to the cost differences and the currently limited value of energy storage, implementation of new facilities is still slow compared to photovoltaic systems. One recognized option to lower cost instantly is the hybridization of CSP with other energy sources, such as natural gas or biomass. Various references exist for the combination of CSP with natural gas in combined cycle plants, also known as Integrated Solar Combined Cycle (ISCC) plants. One problem with current ISCC concepts is the so called ISCC crisis, which occurs when CSP is not contributing and cycle efficiency falls below efficiency levels of solely natural gas only fired combined cycle plants. This paper analyses current ISCC concepts and compares them with two optimised designs. The comparison is based on a Kuraymat type ISCC plant and shows that cycle optimization enables a net capacity increase of 1.4% and additional daily generation of up to 7.9%. The specific investment of the optimised Integrated Solar Combined Cycle plant results in a 0.4% cost increase, which is below the additional net capacity and daily generation increase.

Possibilities of electricity generation from solar and other renewable resources in Turkey

International Nuclear Information System (INIS)

Tasdemiroglu, E.

1993-01-01

The paper begins by reviewing the conventional power generation in the country. Increasing power demand due to rapid industrialization as well as the environmental consequences of power generation will be discussed. The potential of renewable energy resources including solar, biomass, wind, and wave and their role in the power generation will be pointed out. Among the strong alternatives are thermal power plants, and rural electricity production by photovoltaic and by small wind machines. Finally, the technical economic difficulties in adapting renewable electricity generation systems for the conditions of the country will be discussed. (Author) 22 refs

Evaluation end-of-life power generation of a satellite solar array

International Nuclear Information System (INIS)

Taherbaneh, Mohsen; Ghafooifard, H.; Rezaie, A.H.; Rahimi, K.

2011-01-01

Research highlights: → We present detailed design description and necessary considerations for solar panels utilized in a specific space mission. → All sources of losses and degradation of the solar panels are fully taken into account. → We introduce a comprehensive novel approach to investigate the electrical behavior of the solar panels. → We use a simple model to calculate the operating temperature range of the solar panels. → We also calculate Mission End-of-Life electrone fluence using SPENVIS. -- Abstract: Knowing the power generated by of solar arrays in a space missions shall satisfy mission requirements; prediction of the power generated by a solar array used in a space mission is very important and necessary. In this research, a detailed design description and necessary considerations for solar panels utilized in a specific space mission is presented. All sources of losses and degradation of solar panels are fully taken into account. This research emphasizes on investigation, analysis and verification of a manufactured solar assembly for a satellite before launch. Solar panels' generated power should be estimated at the end of the mission. For this purpose, radiation values and temperature operating range are specified for the mission. Panels' temperature operating rate is determined through considering a simple model and different spins for the satellite. Mission end-of-life 1 MeV equivalent dose is calculated by SPENVIS suite software. Finally, a comprehensive novel approach is introduced to investigate the electrical behavior of the solar panels. This approach can be implemented in MATLAB environment to obtain output power characteristics of the solar panels for each specific mission. The results are in full accordance with the mission requirements either in beginning-of-life or end-of-life. Therefore, the power prediction of the designed solar array for the mentioned satellite completely satisfies its mission requirements.

Possibility of EV with solar cells on the new traffic system; Shinkotsu system ni okeru solar car no kanosei

Energy Technology Data Exchange (ETDEWEB)

Fujii, I; Kojima, S [Meiji University, Tokyo (Japan)

1997-11-25

A possibility of a new traffic system was studied for a solar car which is light in weight, small in size and low in speed (cruising speed: 20 km/h) and does not need so much power because of the use for short distance. In the new traffic system, people travel short distance in city by solar car, and use trains for travel between cities. By installing solar cells on roofs, etc. of houses and buildings such as garages around stations, power needed for solar car and incidentally required can be supplied. Assuming the short distance transportation, the car is for one person with a height of luggage space of 70cm, mean length of 165cm, and floor height of 50cm above the ground. In case that the power generation by solar cells (256.5W) is at maximum with no shading during travel on conditions of load weight of 10kg, personnel weight of 70kg, and total weight of 250kg, it was found that solar cells can supply 89% of the required output under test road travel at speed of 20 km/h. A viability of the solar car proposed here is great. A possibility at the time of mode road travel is also studied. 10 refs., 3 figs., 1 tab.

Design and analysis of a dead volume control for a solar Stirling engine with induction generator

International Nuclear Information System (INIS)

Beltrán-Chacon, Ricardo; Leal-Chavez, Daniel; Sauceda, D.; Pellegrini-Cervantes, Manuel; Borunda, Mónica

2015-01-01

In this work, a power generation system dish/Stirling with cavity receiver and an electrical induction generator was simulated. We propose a control system using a variable-dead-volume and analyze its influence on the mechanical performance. A system with a dead volume of 160 cm"3 was designed to control the power and speed of the engine considering annual insolation, mechanical properties of the heater and the limits of frequency and voltage for the systems interconnected to the electricity network. The designed system achieves net efficient solar conversion to electric of 23.38% at an irradiance of 975 W/m"2 and allows an annual increase of 18% of the useful electrical energy compared to a system without control. - Highlights: • Numerical simulation of a nitrogen charged solar Stirling engine for electric power generation. • Design and analysis of a dead volume control for performance increase and power modulation. • Effect of dead space on average working pressure and mass flow rate. • Comparison between dead volume and average pressure control methods. • Impact of Stirling engine control settings on annual generated electric power.

Development and basic photovoltaic characteristics of a solar generator with double-sided silicon cells

International Nuclear Information System (INIS)

Aliev, R.; Mansurov, Kh.

2015-01-01

A new solar generator consisting of double-sided silicon sensing elements is described. The basic photovoltaic parameters of solar generators are made of mono- and polycrystalline silicon solar cells. (author)

Photovoltaic solar system connected to the electric power grid operating as active power generator and reactive power compensator

Energy Technology Data Exchange (ETDEWEB)

Albuquerque, F.L.; Moraes, A.J.; Guimaraes, G.C.; Sanhueza, S.M.R.; Vaz, A.R. [Federal University of Uberlandia (UFU), MG (Brazil)

2009-07-01

In the case of photovoltaic solar systems (PV) acting as a distributed generation (DG), the DC energy obtained is fed through the power-conditioning unit (inverter) to the grid. The majority of contemporary inverters used in DG systems are current source inverters (CSI) operating at unity power factor. If, however, we assume that voltage source inverters (VSI) can be utilized instead of CSI, we can generate reactive power commensurate with the remaining unused capacity at any given point in time. According to the theory of instantaneous power, the reactive and active power of inverter can be regulated by changing the amplitude and the phase of the output voltage of the inverter. Based on this theory, the active power output and the reactive power compensation (RPC) of the system are realized simultaneously. When the insolation is weak or the PV modules are inoperative at night, the RPC feature of PV system can still be used to improve the utilization factor of the inverter. The MATLAB simulation results validate the feasibility of the method. (author)

Robust and Low-Cost Flame-Treated Wood for High-Performance Solar Steam Generation.

Science.gov (United States)

Xue, Guobin; Liu, Kang; Chen, Qian; Yang, Peihua; Li, Jia; Ding, Tianpeng; Duan, Jiangjiang; Qi, Bei; Zhou, Jun

2017-05-03

Solar-enabled steam generation has attracted increasing interest in recent years because of its potential applications in power generation, desalination, and wastewater treatment, among others. Recent studies have reported many strategies for promoting the efficiency of steam generation by employing absorbers based on carbon materials or plasmonic metal nanoparticles with well-defined pores. In this work, we report that natural wood can be utilized as an ideal solar absorber after a simple flame treatment. With ultrahigh solar absorbance (∼99%), low thermal conductivity (0.33 W m -1 K -1 ), and good hydrophilicity, the flame-treated wood can localize the solar heating at the evaporation surface and enable a solar-thermal efficiency of ∼72% under a solar intensity of 1 kW m -2 , and it thus represents a renewable, scalable, low-cost, and robust material for solar steam applications.

Super-hydrophilic copper sulfide films as light absorbers for efficient solar steam generation under one sun illumination

Science.gov (United States)

Guo, Zhenzhen; Ming, Xin; Wang, Gang; Hou, Baofei; Liu, Xinghang; Mei, Tao; Li, Jinhua; Wang, Jianying; Wang, Xianbao

2018-02-01

Solar steam technology is one of the simplest, most direct and effective ways to harness solar energy through water evaporation. Here, we report the development using super-hydrophilic copper sulfide (CuS) films with double-layer structures as light absorbers for solar steam generation. In the double-layer structure system, a porous mixed cellulose ester (MCE) membrane is used as a supporting layer, which enables water to get into the CuS light absorbers through a capillary action to provide continuous water during solar steam generation. The super-hydrophilic property of the double-layer system (CuS/MCE) leads to a thinner water film close to the air-water interface where the surface temperature is sufficiently high, leading to more efficient evaporation (˜80 ± 2.5%) under one sun illumination. Furthermore, the evaporation efficiencies still keep a steady value after 15 cycles of testing. The super-hydrophilic CuS film is promising for practical application in water purification and evaporation as a light absorption material.

Absorption generator for solar-powered air-conditioner

Science.gov (United States)

Lowen, D. J.; Murray, J. G.

1977-01-01

Device passes solar-heated water through coils. Hot lithium Bromide/Water solution leaves through central stand-pipe, and water vapor leaves through refrigerant outlet at top. Matching generation temperature to collector efficiency helps cut costs.

Garrett solar Brayton engine/generator status

Science.gov (United States)

Anson, B.

1982-07-01

The solar advanced gas turbine (SAGT-1) is being developed by the Garrett Turbine Engine Company, for use in a Brayton cycle power conversion module. The engine is derived from the advanced gas turbine (AGT101) now being developd by Garrett and Ford Motor Company for automotive use. The SAGT Program is presently funded for the design, fabrication and test of one engine at Garrett's Phoenix facility. The engine when mated with a solar receiver is called a power conversion module (PCU). The PCU is scheduled to be tested on JPL's test bed concentrator under a follow on phase of the program. Approximately 20 kw of electrical power will be generated.

A solar PV augmented hybrid scheme for enhanced wind power generation through improved control strategy for grid connected doubly fed induction generator

Directory of Open Access Journals (Sweden)

Adikanda Parida

2016-12-01

Full Text Available In this paper, a wind power generation scheme using a grid connected doubly fed induction generator (DFIG augmented with solar PV has been proposed. A reactive power-based rotor speed and position estimation technique with reduced machine parameter sensitivity is also proposed to improve the performance of the DFIG controller. The estimation algorithm is based on model reference adaptive system (MRAS, which uses the air gap reactive power as the adjustable variable. The overall generation reliability of the wind energy conversion system can be considerably improved as both solar and wind energy can supplement each other during lean periods of either of the sources. The rotor-side DC-link voltage and active power generation at the stator terminals of the DFIG are maintained constant with minimum storage battery capacity using single converter arrangement without grid-side converter (GSC. The proposed scheme has been simulated and experimentally validated with a practical 2.5 kW DFIG using dSPACE CP1104 module which produced satisfactory results.

Physical Limits of Solar Energy Conversion in the Earth System.

Science.gov (United States)

Kleidon, Axel; Miller, Lee; Gans, Fabian

2016-01-01

Solar energy provides by far the greatest potential for energy generation among all forms of renewable energy. Yet, just as for any form of energy conversion, it is subject to physical limits. Here we review the physical limits that determine how much energy can potentially be generated out of sunlight using a combination of thermodynamics and observed climatic variables. We first explain how the first and second law of thermodynamics constrain energy conversions and thereby the generation of renewable energy, and how this applies to the conversions of solar radiation within the Earth system. These limits are applied to the conversion of direct and diffuse solar radiation - which relates to concentrated solar power (CSP) and photovoltaic (PV) technologies as well as biomass production or any other photochemical conversion - as well as solar radiative heating, which generates atmospheric motion and thus relates to wind power technologies. When these conversion limits are applied to observed data sets of solar radiation at the land surface, it is estimated that direct concentrated solar power has a potential on land of up to 11.6 PW (1 PW=10(15) W), whereas photovoltaic power has a potential of up to 16.3 PW. Both biomass and wind power operate at much lower efficiencies, so their potentials of about 0.3 and 0.1 PW are much lower. These estimates are considerably lower than the incoming flux of solar radiation of 175 PW. When compared to a 2012 primary energy demand of 17 TW, the most direct uses of solar radiation, e.g., by CSP or PV, have thus by far the greatest potential to yield renewable energy requiring the least space to satisfy the human energy demand. Further conversions into solar-based fuels would be reduced by further losses which would lower these potentials. The substantially greater potential of solar-based renewable energy compared to other forms of renewable energy simply reflects much fewer and lower unavoidable conversion losses when solar

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.

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

Application and design of solar photovoltaic system

International Nuclear Information System (INIS)

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

2011-01-01

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

Quantifying Carbon and distributional benefits of solar home system programs in Bangladesh

OpenAIRE

Wang, Limin; Bandyopadhyay, Sushenjit; Cosgrove-Davies, Mac; Samad, Hussain

2011-01-01

Scaling-up adoption of renewable energy technology, such as solar home systems, to expand electricity access in developing countries can accelerate the transition to low-carbon economic development. Using a purposely collected national household survey, this study quantifies the carbon and distributional benefits of solar home system programs in Bangladesh. Three key findings are generated...

Solar Heating Systems with Evacuated Tubular Solar Collector

DEFF Research Database (Denmark)

Qin, Lin; Furbo, Simon

1998-01-01

Recently different designed evacuated tubular solar collectors were introduced on the market by different Chinese companies. In the present study, investigations on the performance of four different Chinese evacuated tubular collectors and of solar heating systems using these collectors were...... carried out, employing both laboratory test and theoretical calculations. The collectors were tested in a small solar domestic hot water (SDHW) system in a laboratory test facility under realistic conditions. The yearly thermal performance of solar heating systems with these evacuated tubular collectors......, as well as with normal flat-plate collectors was calculated under Danish weather conditions. It is found that, for small SDHW systems with a combi tank design, an increase of 25% -55% net utilized solar energy can be achieved by using these evacuated tubular collectors instead of normal flat...

Baby Solar System

Science.gov (United States)

Currie, Thayne; Grady, Carol

2012-01-01

What did our solar system look like in its infancy,...... when the planets were forming? We cannot travel back in time to take an image of the early solar system, but in principle we can have the next best thing: images of infant planetary systems around Sun-like stars with ages of 1 to 5 million years, the time we think it took for the giant planets to form. Infant exoplanetary systems are critically important because they can help us understand how our solar system fits within the context of planet formation in general. More than 80% of stars are born with gas- and dust-rich disks, and thus have the potential to form planets. Through many methods we have identified more than 760 planetary systems around middle-aged stars like the Sun, but many of these have architectures that look nothing like our solar system. Young planetary systems are important missing links between various endpoints and may help us understand how and when these differences emerge. Well-known star-forming regions in Taurus, Scorpius. and Orion contain stars that could have infant planetary systems. But these stars are much more distant than our nearest neighbors such as Alpha Centauri or Sirius, making it extremely challenging to produce clear images of systems that can reveal signs of recent planet formation, let alone reveal the planets themselves. Recently, a star with the unassuming name LkCa 15 may have given us our first detailed "baby picture" of a young planetary system similar to our solar system. Located about 450 light-years away in the Taurus starforming region. LkCa 15 has a mass comparable to the Sun (0.97 solar mass) and an age of l to 5 million years, comparable to the time at which Saturn and perhaps Jupiter formed. The star is surrounded by a gas-rich disk similar in structure to the one in our solar system from which the planets formed. With new technologies and observing strategies, we have confirmed suspicions that LkCa 15's disk harbors a young planetary system.

Smart solar tanks for small solar domestic hot water systems

DEFF Research Database (Denmark)

Furbo, Simon; Andersen, Elsa; Knudsen, Søren

2005-01-01

Investigation of small SDHW systems based on smart solar tanks are presented. The domestic water in a smart solar tank can be heated both by solar collectors and by means of an auxiliary energy supply system. The auxiliary energy supply system – in this study electric heating elements – heats up...... systems, based on differently designed smart solar tanks and a traditional SDHW system were investigated by means of laboratory experiments and theoretical calculations. The investigations showed that the yearly thermal performance of SDHW systems with smart solar tanks is 5-35% higher than the thermal...... performance of traditional SDHW systems. Estimates indicate that the performance/cost ratio can be improved by up to 25% by using a smart solar tank instead of a traditional tank when the backup energy system is electric heating elements. Further, smart solar tanks are suitable for unknown, variable, large...

Southeast Regional Assessment Study: an assessment of the opportunities of solar electric power generation in the Southeastern United States

Energy Technology Data Exchange (ETDEWEB)

None

1980-07-01

The objective of this study was to identify and assess opportunities for demonstration and large scale deployment of solar electric facilities in the southeast region and to define the technical, economic, and institutional factors that can contribute to an accelerated use of solar energy for electric power generation. Graphs and tables are presented indicating the solar resource potential, siting opportunities, energy generation and use, and socioeconomic factors of the region by state. Solar electric technologies considered include both central station and dispersed solar electric generating facilities. Central stations studied include solar thermal electric, wind, photovoltaic, ocean thermal gradient, and biomass; dispersed facilities include solar thermal total energy systems, wind, and photovoltaic. The value of solar electric facilities is determined in terms of the value of conventional facilities and the use of conventional fuels which the solar facilities can replace. Suitable cost and risk sharing mechanisms to accelerate the commercialization of solar electric technologies in the Southeast are identified. The major regulatory and legal factors which could impact on the commercialization of solar facilities are reviewed. The most important factors which affect market penetration are reviewed, ways to accelerate the implementation of these technologies are identified, and market entry paths are identified. Conclusions and recommendations are presented. (WHK)

Long-term field test of solar PV power generation using one-axis 3-position sun tracker

KAUST Repository

Huang, B.J.

2011-09-01

The 1 axis-3 position (1A-3P) sun tracking PV was built and tested to measure the daily and long-term power generation of the solar PV system. A comparative test using a fixed PV and a 1A-3P tracking PV was carried out with two identical stand-alone solar-powered LED lighting systems. The field test in the particular days shows that the 1A-3P tracking PV can generate 35.8% more electricity than the fixed PV in a partly-cloudy weather with daily-total solar irradiation HT=11.7MJ/m2day, or 35.6% in clear weather with HT=18.5MJ/m2day. This indicates that the present 1A-3P tracking PV can perform very close to a dual-axis continuous tracking PV (Kacira et al., 2004). The long-term outdoor test results have shown that the increase of daily power generation of 1A-3P tracking PV increases with increasing daily-total solar irradiation. The increase of monthly-total power generation for 1A-3P sun tracking PV is between 18.5-28.0%. The total power generation increase in the test period from March 1, 2010 to March 31, 2011, is 23.6% in Taipei (an area of low solar energy resource). The long-term performance of the present 1X-3P tracking PV is shown very close to the 1-axis continuous tracking PV in Taiwan (Chang, 2009). If the 1A-3P tracking PV is used in the area of high solar energy resource with yearly-average HT>17MJ/m2day, the increase of total long-term power generation with respect to fixed PV will be higher than 37.5%. This is very close to that of dual-axis continuous tracking PV. The 1A-3P tracker can be easily mounted on the wall of a building. The cost of the whole tracker is about the same as the regular mounting cost of a conventional rooftop PV system. This means that there is no extra cost for 1A-3P PV mounted on buildings. The 1A-3P PV is quite suitable for building-integrated applications. © 2011 Elsevier Ltd.

Multiple exciton generation in quantum dot-based solar cells

Science.gov (United States)

Goodwin, Heather; Jellicoe, Tom C.; Davis, Nathaniel J. L. K.; Böhm, Marcus L.

2018-01-01

Multiple exciton generation (MEG) in quantum-confined semiconductors is the process by which multiple bound charge-carrier pairs are generated after absorption of a single high-energy photon. Such charge-carrier multiplication effects have been highlighted as particularly beneficial for solar cells where they have the potential to increase the photocurrent significantly. Indeed, recent research efforts have proved that more than one charge-carrier pair per incident solar photon can be extracted in photovoltaic devices incorporating quantum-confined semiconductors. While these proof-of-concept applications underline the potential of MEG in solar cells, the impact of the carrier multiplication effect on the device performance remains rather low. This review covers recent advancements in the understanding and application of MEG as a photocurrent-enhancing mechanism in quantum dot-based photovoltaics.

PV solar system feasibility study

International Nuclear Information System (INIS)

Ashhab, Moh’d Sami S.; Kaylani, Hazem; Abdallah, Abdallah

2013-01-01

Highlights: ► This research studies the feasibility of PV solar systems. ► The aim is to develop the theory and application of a hybrid system. ► Relevant research topics are reviewed and some of them are discussed in details. ► A prototype of the PV solar system is designed and built. - Abstract: This research studies the feasibility of PV solar systems and aims at developing the theory and application of a hybrid system that utilizes PV solar system and another supporting source of energy to provide affordable heating and air conditioning. Relevant research topics are reviewed and some of them are discussed in details. Solar heating and air conditioning research and technology exist in many developed countries. To date, the used solar energy has been proved to be inefficient. Solar energy is an abundant source of energy in Jordan and the Middle East; with increasing prices of oil this source is becoming more attractive alternative. A good candidate for the other system is absorption. The overall system is designed such that it utilizes solar energy as a main source. When the solar energy becomes insufficient, electricity or diesel source kicks in. A prototype of the PV solar system that operates an air conditioning unit is built and proper measurements are collected through a data logging system. The measured data are plotted and discussed, and conclusions regarding the system performance are extracted.

Small Hybrid Solar Power System

OpenAIRE

Kane, El Hadj Malick; Larrain, Diego; Favrat, Daniel

2001-01-01

This paper introduces a novel of mini-hybrid solar power plant integrating a field of solar concentrators, two superposed Organic Rankine Cycles (ORC) and a (bio)Diesel engine. Turbines for the organic Rankine Cycles are hermetic scroll expander-generators. Sun tracking solar collectors are composed of rows of flat mirror bands (CEP) arranged in a plane, which focus the solar energy onto a collector tube similar to those used in SEGS plant in California. The wast...

Small Hybrid Solar Power System

OpenAIRE

Kane, El Hadj Malick; Favrat, Daniel; Larrain, Diego; Allani, Yassine

2003-01-01

This paper introduces a novel of mini-hybrid solar power plant integrating a field of solar concentrators, two superposed Organic Rankine Cycles (ORC) and a (bio)Diesel engine. Turbines for the organic Rankine Cycles are hermetic scroll expander-generators. Sun tracking solar collectors are composed of rows of flat mirror bands (CEP) arranged in a plane, which focus the solar energy onto a collector tube similar to those used in SEGS plant in California. The waste heat from both...

Vectorial Command of Induction Motor Pumping System Supplied by a Photovoltaic Generator

Science.gov (United States)

Makhlouf, Messaoud; Messai, Feyrouz; Benalla, Hocine

2011-01-01

With the continuous decrease of the cost of solar cells, there is an increasing interest and needs in photovoltaic (PV) system applications following standard of living improvements. Water pumping system powered by solar-cell generators are one of the most important applications. The fluctuation of solar energy on one hand, and the necessity to optimise available solar energy on the other, it is useful to develop new efficient and flexible modes to control motors that entrain the pump. A vectorial control of an asynchronous motor fed by a photovoltaic system is proposed. This paper investigates a photovoltaic-electro mechanic chain, composed of a PV generator, DC-AC converter, a vector controlled induction motor and centrifugal pump. The PV generator is forced to operate at its maximum power point by using an appropriate search algorithm integrated in the vector control. The optimization is realized without need to adding a DC-DC converter to the chain. The motor supply is also ensured in all insolation conditions. Simulation results show the effectiveness and feasibility of such an approach.

Compact solar autoclave based on steam generation using broadband light-harvesting nanoparticles.

Science.gov (United States)

Neumann, Oara; Feronti, Curtis; Neumann, Albert D; Dong, Anjie; Schell, Kevin; Lu, Benjamin; Kim, Eric; Quinn, Mary; Thompson, Shea; Grady, Nathaniel; Nordlander, Peter; Oden, Maria; Halas, Naomi J

2013-07-16

The lack of readily available sterilization processes for medicine and dentistry practices in the developing world is a major risk factor for the propagation of disease. Modern medical facilities in the developed world often use autoclave systems to sterilize medical instruments and equipment and process waste that could contain harmful contagions. Here, we show the use of broadband light-absorbing nanoparticles as solar photothermal heaters, which generate high-temperature steam for a standalone, efficient solar autoclave useful for sanitation of instruments or materials in resource-limited, remote locations. Sterilization was verified using a standard Geobacillus stearothermophilus-based biological indicator.

Compact solar autoclave based on steam generation using broadband light-harvesting nanoparticles

Science.gov (United States)

Neumann, Oara; Feronti, Curtis; Neumann, Albert D.; Dong, Anjie; Schell, Kevin; Lu, Benjamin; Kim, Eric; Quinn, Mary; Thompson, Shea; Grady, Nathaniel; Nordlander, Peter; Oden, Maria; Halas, Naomi J.

2013-01-01

The lack of readily available sterilization processes for medicine and dentistry practices in the developing world is a major risk factor for the propagation of disease. Modern medical facilities in the developed world often use autoclave systems to sterilize medical instruments and equipment and process waste that could contain harmful contagions. Here, we show the use of broadband light-absorbing nanoparticles as solar photothermal heaters, which generate high-temperature steam for a standalone, efficient solar autoclave useful for sanitation of instruments or materials in resource-limited, remote locations. Sterilization was verified using a standard Geobacillus stearothermophilus-based biological indicator. PMID:23836642

Extremely Black Vertically Aligned Carbon Nanotube Arrays for Solar Steam Generation.

Science.gov (United States)

Yin, Zhe; Wang, Huimin; Jian, Muqiang; Li, Yanshen; Xia, Kailun; Zhang, Mingchao; Wang, Chunya; Wang, Qi; Ma, Ming; Zheng, Quan-Shui; Zhang, Yingying

2017-08-30

The unique structure of a vertically aligned carbon nanotube (VACNT) array makes it behave most similarly to a blackbody. It is reported that the optical absorptivity of an extremely black VACNT array is about 0.98-0.99 over a large spectral range of 200 nm-200 μm, inspiring us to explore the performance of VACNT arrays in solar energy harvesting. In this work, we report the highly efficient steam generation simply by laminating a layer of VACNT array on the surface of water to harvest solar energy. It is found that under solar illumination the temperature of upper water can significantly increase with obvious water steam generated, indicating the efficient solar energy harvesting and local temperature rise by the thin layer of VACNTs. We found that the evaporation rate of water assisted by VACNT arrays is 10 times that of bare water, which is the highest ratio for solar-thermal-steam generation ever reported. Remarkably, the solar thermal conversion efficiency reached 90%. The excellent performance could be ascribed to the strong optical absorption and local temperature rise induced by the VACNT layer, as well as the ultrafast water transport through the VACNT layer due to the frictionless wall of CNTs. Based on the above, we further demonstrated the application of VACNT arrays in solar-driven desalination.

Fiscal 1974 Sunshine Project result report. Research on solar energy utilization systems (solar furnace); 1974 nendo taiyo energy riyo system chosa kenkyu. Taiyoro

Energy Technology Data Exchange (ETDEWEB)

NONE

1975-03-01

In fiscal 1974, analysis was made on the concept design of solar furnace hardware, and utilization and use purpose of solar furnaces as high-temperature industrial heat source. Detailed survey was also made on the history of high- temperature solar furnaces. Based on the history of large- scale solar furnaces and the current state of some industries consuming a large amount of thermal energy, wide consideration was made on the applicability of large-scale solar furnaces as heat source in the future. Although various applications of large-scale solar furnaces are expected in the future, their current main applications are production of high-melting point materials, research on high-temperature physical properties, production of silicon, and solar heat power generation. A solar furnace is mainly composed of a parabolic reflector and heliostat plane reflector as optical system. It is necessary for practical industrial use of solar furnaces to study on furnace core design, profitability, installation site, temperature control, and reflector maintenance enough. (NEDO)

Who's hot, who's not? Effects of concentrating solar power heliostats on soil temperature at Ivanpah Solar Electric Generating System, Mojave Desert, USA

Science.gov (United States)

Grodsky, S.; Hernandez, R. R.

2017-12-01

Solar energy development may function as a contemporary, anthropogenic driver of disturbance when sited in natural ecosystems. Orientation and density of solar modules, including heliostats at concentrating solar power (CSP) facilities, may affect soils via shading and altered surface-water flow. Meanwhile, soil attributes like temperature and moisture may affect nutrient cycling, plant germination and growth, and soil biota. We tested effects of CSP heliostats on soil temperature at Ivanpah Solar Electric Generating System (ISEGS) in the Mojave Desert, USA. We implemented experimental treatments based on preconstruction rare plant [e.g., Mojave milkweed (Asclepias nyctaginifolia)] protection areas (hereafter "halos"), site preparation activities, and heliostat density throughout three, replicated CSP blocks (i.e., tower and associated heliostats), including: (1) No Halos (Bladed) - high site preparation intensity, high heliostat density immediately surrounding towers; (2) No Halos (Mowed) - moderate site preparation intensity, moderate to low heliostat density as distance increases from towers; and (3) Halos - no site preparation, no heliostats. We also established control sites within 1,600 km of ISEGS in undisturbed desert. We observed significant differences in soil temperature across treatments. We recorded significantly lower soil temperatures in the No Halos (Bladed) treatments (26.7°C) and No Halos (Mowed) treatments (29.9°C) than in the Halos treatments (32.9°C) and controls (32.1°C). We also determined that soil temperatures in the Halos treatments and controls did not significantly differ. Our results indicated that shading from high-density heliostat configuration significantly reduced soil temperature relative to low-density heliostat configuration and areas without CSP. Shading from heliostats and consequential fluctuation in soil temperatures may affect local-scale distribution of flora and fauna, leading to altered "bottom-up" ecological

Development of a solar-powered residential air conditioner: System optimization preliminary specification

Science.gov (United States)

Rousseau, J.; Hwang, K. C.

1975-01-01

Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

Homemade Solar Systems

Science.gov (United States)

1981-01-01

Through the use of NASA Tech Briefs, Peter Kask, was able to build a solarized domestic hot water system. Also by applying NASA's solar energy design information, he was able to build a swimming pool heating system with minimal outlay for materials.

Evaluating the limits of solar photovoltaics (PV) in traditional electric power systems

International Nuclear Information System (INIS)

Denholm, Paul; Margolis, Robert M.

2007-01-01

In this work, we examine some of the limits to large-scale deployment of solar photovoltaics (PV) in traditional electric power systems. Specifically, we evaluate the ability of PV to provide a large fraction (up to 50%) of a utility system's energy by comparing hourly output of a simulated large PV system to the amount of electricity actually usable. The simulations use hourly recorded solar insolation and load data for Texas in the year 2000 and consider the constraints of traditional electricity generation plants to reduce output and accommodate intermittent PV generation. We find that under high penetration levels and existing grid-operation procedures and rules, the system will have excess PV generation during certain periods of the year. Several metrics are developed to examine this excess PV generation and resulting costs as a function of PV penetration at different levels of system flexibility. The limited flexibility of base load generators produces increasingly large amounts of unusable PV generation when PV provides perhaps 10-20% of a system's energy. Measures to increase PV penetration beyond this range will be discussed and quantified in a follow-up analysis

Development of an Advanced Grid-Connected PV-ECS System Considering Solar Energy Estimation

Science.gov (United States)

Rahman, Md. Habibur; Yamashiro, Susumu; Nakamura, Koichi

In this paper, the development and the performance of a viable distributed grid-connected power generation system of Photovoltaic-Energy Capacitor System (PV-ECS) considering solar energy estimation have been described. Instead of conventional battery Electric Double Layer Capacitors (EDLC) are used as storage device and Photovoltaic (PV) panel to generate power from solar energy. The system can generate power by PV, store energy when the demand of load is low and finally supply the stored energy to load during the period of peak demand. To realize the load leveling function properly the system will also buy power from grid line when load demand is high. Since, the power taken from grid line depends on the PV output power, a procedure has been suggested to estimate the PV output power by calculating solar radiation. In order to set the optimum value of the buy power, a simulation program has also been developed. Performance of the system has been studied for different load patterns in different weather conditions by using the estimated PV output power with the help of the simulation program.

Performance of a Solar Heating System with Photovoltaic Thermal Hybrid Collectors and Heat Pump

DEFF Research Database (Denmark)

Dannemand, Mark; Furbo, Simon; Perers, Bengt

2017-01-01

. When the solar collectors are unable to supply the heat demand an auxiliary heat source is used. Heat pumps can generate this heat. Liquid/water heat pumps have better performance than air/water heat pumps in cold climates but requires installation of a tubing system for the cold side of the heat pump....... The tubes are typically placed in the ground, requires a significant land area and increase the installation cost. A new system design of a solar heating system with two storage tanks and a liquid/water heat pump is presented. The system consists of PVT collectors that generate both heat and electricity......The energy consumption in buildings accounts for a large part of the World’s CO2 emissions. Much energy is used for appliances, domestic hot water preparation and space heating. In solar heating systems, heat is captured by solar collectors when the sun is shining and used for heating purposes...

Self-advertising: PV systems on solar factories; Werbung in eigener Sache. PV-Anlagen an Solarfabriken

Energy Technology Data Exchange (ETDEWEB)

Trojek, S.

2007-10-02

The contribution investigates if producers of solar systems are also users of solar systems; it looks into the systems installed by German and Japanese companies on their own buildings, into the uses made of the electric power generated, and the experience gained with their own systems. (orig.)

Application of Airborne LiDAR Data and Geographic Information Systems (GIS to Develop a Distributed Generation System for the Town of Normal, IL

Directory of Open Access Journals (Sweden)

Jin H. Jo

2015-03-01

Full Text Available Distributed generation allows a variety of small, modular power-generating technologies to be combined with load management and energy storage systems to improve the quality and reliability of our electricity supply. As part of the US Environmental Protection Agency's effort to reduce CO2 emissions from existing power plants by 30% by 2030, distributed generation through solar photovoltaic systems provides a viable option for mitigating the negative impacts of centralized fossil fuel plants. This study conducted a detailed analysis to identify the rooftops in a town in Central Illinois that are suitable for distributed generation solar photovoltaic systems with airborn LiDAR data and to quantify their energy generation potential with an energy performance model. By utilizing the available roof space of the 9,718 buildings in the case study area, a total of 39.27 MW solar photovoltaic systems can provide electrical generation of 53,061 MWh annually. The unique methodology utilized for this assessment of a town's solar potential provides an effective way to invest in a more sustainable energy future and ensure economic stability.

Modeling and characteristics analysis of hybrid cooling-tower-solar-chimney system

International Nuclear Information System (INIS)

Zou, Zheng; He, Suoying

2015-01-01

Highlights: • A 3-D model for hybrid cooling-tower-solar-chimney system is developed. • The inclusion of heat exchangers into solar chimney boosts the power output. • The huge jump in power output is at the expense of heat dissipation capacity. • The heat exchanger as second heat source has greater impact on system performance. - Abstract: The hybrid cooling-tower-solar-chimney system (HCTSC), combining solar chimney with natural draft dry cooling tower, generates electricity and dissipates waste heat for the coupled geothermal power plant simultaneously. Based on a developed 3-D model, performance comparisons between the HCTSC system, solar chimney and natural draft dry cooling tower were performed in terms of power output of turbine and heat dissipation capacity. Results show that compared to the traditional solar chimney with similar geometric dimensions, HCTSC system can achieve over 20 times increase in the power output of turbine. However, this huge jump in power output is at the expense of heat dissipation capacity, which may lead to the malfunction of the coupled thermal power plant. By increasing the heat transfer area of the heat exchanger, the HCTSC system can manage to recover its heat dissipation capacity

Numerical analysis on the performance of solar chimney power plant system

International Nuclear Information System (INIS)

Xu Guoliang; Ming Tingzhen; Pan Yuan; Meng Fanlong; Zhou Cheng

2011-01-01

Power generating technology based on renewable energy resources will definitely become a new trend of future energy utilization. Numerical simulations on air flow, heat transfer and power output characteristics of a solar chimney power plant model with energy storage layer and turbine similar to the Spanish prototype were carried out in this paper, and mathematical model of flow and heat transfer for the solar chimney power plant system was established. The influences of solar radiation and pressure drop across the turbine on the flow and heat transfer, output power and energy loss of the solar chimney power plant system were analyzed. The numerical simulation results reveal that: when the solar radiation and the turbine efficiency are 600 W/m 2 and 80%, respectively, the output power of the system can reach 120 kW. In addition, large mass flow rate of air flowing through the chimney outlet become the main cause of energy loss in the system, and the collector canopy also results in large energy loss.

Analysis of a feasible trigeneration system taking solar energy and biomass as co-feeds

International Nuclear Information System (INIS)

Zhang, Xiaofeng; Li, Hongqiang; Liu, Lifang; Zeng, Rong; Zhang, Guoqiang

2016-01-01

Highlights: • A feasible trigeneration system is proposed to generate power, heating and cooling. • The steam for biomass gasification process is provided by solar energy. • The thermodynamic properties of the proposed system are investigated. • Effects of ER and SBR on gasification process is presented. • The sensitivity of the economic performance of trigeneration system is evaluated. - Abstract: The trigeneration systems are widely used owing to high efficiency, low greenhouse gas emission and high reliability. Especially, those trigeneration systems taking renewable energy as primary input are paid more and more attention. This paper presents a feasible trigeneration system, which realizes biomass and solar energy integrating effective utilization according to energy cascade utilization and energy level upgrading of chemical reaction principle. In the proposed system, the solar energy with mid-and-low temperature converted to the chemical energy of bio-gas through gasification process, then the bio-gas will be taken as the fuel for internal combustion engine (ICE) to generate electricity. The jacket water as a byproduct generated from ICE is utilized in a liquid desiccant unit for providing desiccant capacity. The flue gas is transported into an absorption chiller and heat exchanger consequently, supplying chilled water and domestic hot water. The thermodynamic performance of the trigeneration system was investigated by the help of Aspen plus. The results indicate that the overall energy efficiency and the electrical efficiency of the proposed system in case study are 77.4% and 17.8%, respectively. The introduction of solar energy decreases the consumption of biomass, and the solar thermal energy input fraction is 8.6%. In addition, the primary energy saving ratio and annual total cost saving ratio compared with the separated generation system are 16.7% and 25.9%, respectively.

Variational method for the minimization of entropy generation in solar cells

Energy Technology Data Exchange (ETDEWEB)

Smit, Sjoerd; Kessels, W. M. M., E-mail: w.m.m.kessels@tue.nl [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2015-04-07

In this work, a method is presented to extend traditional solar cell simulation tools to make it possible to calculate the most efficient design of practical solar cells. The method is based on the theory of nonequilibrium thermodynamics, which is used to derive an expression for the local entropy generation rate in the solar cell, making it possible to quantify all free energy losses on the same scale. The framework of non-equilibrium thermodynamics can therefore be combined with the calculus of variations and existing solar cell models to minimize the total entropy generation rate in the cell to find the most optimal design. The variational method is illustrated by applying it to a homojunction solar cell. The optimization results in a set of differential algebraic equations, which determine the optimal shape of the doping profile for given recombination and transport models.

An illustrative note on the system price effect of wind and solar power. The German case

Energy Technology Data Exchange (ETDEWEB)

Jaegemann, Cosima

2014-07-15

Exposing wind and solar power to the market price signal allows for cost-efficient investment decisions, as it incentivizes investors to account for the marginal value (MV{sup el}) of renewable energy technologies. As shown by Lamont (2008), the MV{sup el} of wind and solar power units depends on their penetration level. More specifically, the MV el of wind and solar power units is a function of the respective unit's capacity factor and the covariance between its generation profile and the system marginal costs. The latter component of the MV{sup el} (i.e., the covariance) is found to decline as the wind and solar power penetration increases, displacing dispatchable power plants with higher short-run marginal costs of power production and thus reducing the system marginal costs in all generation hours. This so called 'system price effect' is analyzed in more detail in this paper. The analysis complements the work Lamont (2008) in two regards. First of all, an alternative expression for the MV{sup el} of wind and solar power units is derived, which shows that the MV{sup el} of fluctuating renewable energy technologies depends not only on their own penetration level but also on a variety of other parameters that are specific to the electricity system. Second, based on historical wholesale prices and wind and solar power generation data for Germany, a numerical 'ceteris paribus' example for Germany is presented which illustrates that the system price effect is already highly relevant for both wind and solar power generation in Germany.

An illustrative note on the system price effect of wind and solar power. The German case

International Nuclear Information System (INIS)

Jaegemann, Cosima

2014-01-01

Exposing wind and solar power to the market price signal allows for cost-efficient investment decisions, as it incentivizes investors to account for the marginal value (MV el ) of renewable energy technologies. As shown by Lamont (2008), the MV el of wind and solar power units depends on their penetration level. More specifically, the MV el of wind and solar power units is a function of the respective unit's capacity factor and the covariance between its generation profile and the system marginal costs. The latter component of the MV el (i.e., the covariance) is found to decline as the wind and solar power penetration increases, displacing dispatchable power plants with higher short-run marginal costs of power production and thus reducing the system marginal costs in all generation hours. This so called 'system price effect' is analyzed in more detail in this paper. The analysis complements the work Lamont (2008) in two regards. First of all, an alternative expression for the MV el of wind and solar power units is derived, which shows that the MV el of fluctuating renewable energy technologies depends not only on their own penetration level but also on a variety of other parameters that are specific to the electricity system. Second, based on historical wholesale prices and wind and solar power generation data for Germany, a numerical 'ceteris paribus' example for Germany is presented which illustrates that the system price effect is already highly relevant for both wind and solar power generation in Germany.

Designing and Simulation of a Two-Axis Solar Tracking System by Exact Relations of Solar Angles

Directory of Open Access Journals (Sweden)

Faezeh Esmaili Ranjbar

2013-01-01

Full Text Available In this study, a system has been designed and simulated to track sunlight, which identifies sun location based on the exact relations of solar angles and without any optical sensor. In fact the relations which have been used in this study are far more accurate compared to similar cases, because of using the "equation of time" and reducing the tracking time of every 15 minutes. In this system, an economical micro-controller has been used to generate the necessary orders to control system and two stepper motors for powering solar array. By adding a real-time clock IC (RTC to angle differentiation circuit, dynamic plane has improved.

Renewable Energy Systems: Development and Perspectives of a Hybrid Solar-Wind System

Directory of Open Access Journals (Sweden)

C. Shashidhar

2012-02-01

Full Text Available Considering the intermittent natural energy resources and the seasonal un-balance, a phtovoltaic-wind hybrid electrical power supply system was developed to accommodate remote locations where a conventional grid connection is inconvenient or expensive. However, the hybrid system can also be applied with grid connection and owners are allowed to sell excessive power back to the electric utility. The proposed set-up consists of a photo-voltaic solar-cell array, a mast mounted wind generator, lead-acid storage batteries, an inverter unit to convert DC to AC, electrical lighting loads, electrical heating loads, several fuse and junction boxes and associated wiring, and test instruments for measuring voltages, currents, power factors, and harmonic contamination data throughout the system. The proposed hybrid solar-wind power generating system can be extensively used to illustrate electrical concepts in hands-on laboratories and also for demonstrations in the Industrial Technology curriculum. This paper describes an analysis of local PV-wind hybrid systems for supplying electricity to a private house, farmhouse or small company with electrical power depending on the site needs. The major system components, work principle and specific working condition are presented.

Research and development of evaluation system for photovoltaic power generation system. Research and development on evaluation technology of photovoltaic power generating systems; Taiyoko hatsuden system hyoka gijutsu no kenkyu kaihatsu. System hyoka gijutsu no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

Tatsuta, M [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

1994-12-01

This paper reports the study results on R and D of evaluation technology for photovoltaic power generating systems in fiscal 1994. (1) On preparation of test facility and measuring instrument, the pyrheliometer with a photovoltaic device as sensor was developed. (2) On collection and analysis of data, operation data of interconnection system, stand alone system, and water pump system were collected, and energy flow was analyzed. The following were also analyzed: time variation of a-Si solar cell modules, fluctuation correction factor of spectrum response, that of nonlinear response of crystalline solar cells, effect of solar radiation intensity and wind velocity on temperature rise of modules, and correction factor of DC circuit losses. (3) On on-site measurement technology, the array output measuring instrument was developed on the basis of capacitor charge system. (4) On simulation technology, simulation analyses of energy flow, optimum capacity of interconnection systems, correction factor of solar radiation, and capacity of array storage batteries were conducted. 3 figs., 6 tabs.

Development of a tube receiver for a solar-hybrid microturbine system

OpenAIRE

Amsbeck, Lars; Buck, Reiner; Heller, Peter; Jedamski, Jens; Uhlig, Ralf

2008-01-01

Solar-hybrid microturbine systems with cogeneration offer new possibilities for the generation of electricity and heat or air conditioning. The solar receiver is an important component of such a system. For a prototype system demo project a tube receiver for a 100kWe microturbine system is currently under development. The receiver is designed for air preheating up to 800°C at a pressure of 4.5 barabs. The challenge of the design is to find the right compromise between high efficiency, low pre...

Assessment of distributed solar power systems: Issues and impacts

Science.gov (United States)

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

1982-11-01

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

International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen: Book of Abstracts

Energy Technology Data Exchange (ETDEWEB)

McConnell, R.; Symko-Davies, M.; Hayden, H.

2005-05-01

The International Conference on Solar Concentrators for the Generation of Electricity or Hydrogen provides an opportunity to learn about current significant research on solar concentrators for generating electricity or hydrogen. The conference will emphasize in-depth technical discussions of recent achievements in technologies that convert concentrated solar radiation to electricity or hydrogen, with primary emphasis on photovoltaic (PV) technologies. Very high-efficiency solar cells--above 37%--were recently developed, and are now widely used for powering satellites. This development demands that we take a fresh look at the potential of solar concentrators for generating low-cost electricity or hydrogen. Solar electric concentrators could dramatically overtake other PV technologies in the electric utility marketplace because of the low capital cost of concentrator manufacturing facilities and the larger module size of concentrators. Concentrating solar energy also has advantages for th e solar generation of hydrogen. Around the world, researchers and engineers are developing solar concentrator technologies for entry into the electricity generation market and several have explored the use of concentrators for hydrogen production. The last conference on the subject of solar electric concentrators was held in November of 2003 and proved to be an important opportunity for researchers and developers to share new and crucial information that is helping to stimulate projects in their countries.

A Model for Optimizing the Combination of Solar Electricity Generation, Supply Curtailment, Transmission and Storage

Science.gov (United States)

Perez, Marc J. R.

With extraordinary recent growth of the solar photovoltaic industry, it is paramount to address the biggest barrier to its high-penetration across global electrical grids: the inherent variability of the solar resource. This resource variability arises from largely unpredictable meteorological phenomena and from the predictable rotation of the earth around the sun and about its own axis. To achieve very high photovoltaic penetration, the imbalance between the variable supply of sunlight and demand must be alleviated. The research detailed herein consists of the development of a computational model which seeks to optimize the combination of 3 supply-side solutions to solar variability that minimizes the aggregate cost of electricity generated therefrom: Storage (where excess solar generation is stored when it exceeds demand for utilization when it does not meet demand), interconnection (where solar generation is spread across a large geographic area and electrically interconnected to smooth overall regional output) and smart curtailment (where solar capacity is oversized and excess generation is curtailed at key times to minimize the need for storage.). This model leverages a database created in the context of this doctoral work of satellite-derived photovoltaic output spanning 10 years at a daily interval for 64,000 unique geographic points across the globe. Underpinning the model's design and results, the database was used to further the understanding of solar resource variability at timescales greater than 1-day. It is shown that--as at shorter timescales--cloud/weather-induced solar variability decreases with geographic extent and that the geographic extent at which variability is mitigated increases with timescale and is modulated by the prevailing speed of clouds/weather systems. Unpredictable solar variability up to the timescale of 30 days is shown to be mitigated across a geographic extent of only 1500km if that geographic extent is oriented in a north

Optimization of degradation of Reactive Black 5 (RB5) and electricity generation in solar photocatalytic fuel cell system.

Science.gov (United States)

Khalik, Wan Fadhilah; Ho, Li-Ngee; Ong, Soon-An; Voon, Chun-Hong; Wong, Yee-Shian; Yusoff, NikAthirah; Lee, Sin-Li; Yusuf, Sara Yasina

2017-10-01

The photocatalytic fuel cell (PFC) system was developed in order to study the effect of several operating parameters in degradation of Reactive Black 5 (RB5) and its electricity generation. Light irradiation, initial dye concentration, aeration, pH and cathode electrode are the operating parameters that might give contribution in the efficiency of PFC system. The degradation of RB5 depends on the presence of light irradiation and solar light gives better performance to degrade the azo dye. The azo dye with low initial concentration decolorizes faster compared to higher initial concentration and presence of aeration in PFC system would enhance its performance. Reactive Black 5 rapidly decreased at higher pH due to the higher amount of OH generated at higher pH and Pt-loaded carbon (Pt/C) was more suitable to be used as cathode in PFC system compared to Cu foil and Fe foil. The rapid decolorization of RB5 would increase their voltage output and in addition, it would also increase their V oc , J sc and P max . The breakage of azo bond and aromatic rings was confirmed through UV-Vis spectrum and COD analysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Generation of typical solar radiation data for different climates of China

International Nuclear Information System (INIS)

Zang, Haixiang; Xu, Qingshan; Bian, Haihong

2012-01-01

In this study, typical solar radiation data are generated from both measured data and synthetic generation for 35 stations in six different climatic zones of China. (1) By applying the measured weather data during at least 10 years from 1994 to 2009, typical meteorological years (TMYs) for 35 cities are generated using the Finkelstein–Schafer statistical method. The cumulative distribution function (CDF) of daily global solar radiation (DGSR) for each year is compared with the CDF of DGSR for the long-term years in six different climatic stations (Sanya, Shanghai, Zhengzhou, Harbin, Mohe and Lhasa). The daily global solar radiation as typical data obtained from the TMYs are presented in the Table. (2) Based on the recorded global radiation data from at least 10 years, a new daily global solar radiation model is developed with a sine and cosine wave (SCW) equation. The results of the proposed model and other empirical regression models are compared with measured data using different statistical indicators. It is found that solar radiation data, calculated by the new model, are superior to these from other empirical models at six typical climatic zones. In addition, the novel SCW model is tested and applied for 35 stations in China. -- Highlights: ► Both TMY method and synthetic generation are used to generate solar radiation data. ► The latest and accurate long term weather data in six different climates are applied. ► TMYs using new weighting factors of 8 weather indices for 35 regions are obtained. ► A new sine and cosine wave model is proposed and utilized for 35 major stations. ► Both TMY method and the proposed regression model perform well on monthly bases.

Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis of orbital systems

Science.gov (United States)

1976-01-01

Program plans, schedules, and costs are determined for a synchronous orbit-based power generation and relay system. Requirements for the satellite solar power station (SSPS) and the power relay satellite (PRS) are explored. Engineering analysis of large solar arrays, flight mechanics and control, transportation, assembly and maintenance, and microwave transmission are included.

Solar heating systems for houses. A design handbook for solar combisystems

International Nuclear Information System (INIS)

Weiss, W.

2003-11-01

A handbook giving guidance on systems for providing combined solar space heating and solar water heating for houses has been produced by an international team. The guidance focuses on selection of the optimum combi-system for groups of single-family houses and multi-family houses. Standard classification and evaluation procedures are described. The book should be a valuable tool for building engineers, architects, solar manufacturers and installers of solar solar energy systems, and anyone interested in optimizing combined water and space heating solar systems

ANN based optimization of a solar assisted hybrid cooling system in Turkey

Energy Technology Data Exchange (ETDEWEB)

Ozgur, Arif; Yetik, Ozge; Arslan, Oguz [Mechanical Eng. Dept., Engineering Faculty, Dumlupinar University (Turkey)], email: maozgur@dpu.edu.tr, email: ozgeyetik@dpu.edu.tr, email: oarslan@dpu.edu.tr

2011-07-01

This study achieved optimization of a solar assisted hybrid cooling system with refrigerants such as R717, R141b, R134a and R123 using an artificial neural network (ANN) model based on average total solar radiation, ambient temperature, generator temperature, condenser temperature, intercooler temperature and fluid types. ANN is a new tool; it works rapidly and can thus be a solution for design and optimization of complex power cycles. A unique flexible ANN algorithm was introduced to evaluate the solar ejector cooling systems because of the nonlinearity of neural networks. The conclusion was that the best COPs value obtained with the ANN is 1.35 and COPc is 3.03 when the average total solar radiation, ambient temperature, generator temperature, condenser temperature, intercooler temperature and algorithm are respectively 674.72 W/m2, 17.9, 80, 15 and 13 degree celsius and LM with 14 neurons in single hidden layer, for R717.

Prospects to solar energy power generation in space. Uchu taiyo hatsuden eno tenbo

Energy Technology Data Exchange (ETDEWEB)

Kudo, I. (Electrotechnical Laboratory, Tsukuba (Japan))

1993-05-01

Solar energy power generation in space uses large arrays of solar cells developed on a geosynchronous orbit to obtain electric energy, which is transmitted to the earth using microwaves. The idea had already been advocated in 1968, which was followed a decade later by joint discussions done by NASA and DOE. The concept intended to take care of the U.S. power demand by using 60 power plant satellites, each having an output of 5 GW. This expanse of the scale, regarded reasonable even today, calls for the solar cell arrays in space spreading over an area of 10 km [times] 5 km if silicon solar cells with a conversion efficiency of 15% are used, and rectenna on the ground (a received wave converting facility) forming an ellipse of 10 km [times] 13 km (assuming a location at the north latitude of 36[degree]). Although there are a number of problems in the idea such as transportation means to lift construction materials into the space and effect of microwaves on the ionosphere and the ecosystems, the Agency of Industrial Science and Technology organized a 'committee for investigating and studying the space power generation systems' in the fiscal year 1991, and has been moving discussions forward since then. 7 refs., 5 figs.

Evaluating the potential of concentrating solar power generation in Northwestern India

International Nuclear Information System (INIS)

Purohit, Ishan; Purohit, Pallav; Shekhar, Shashaank

2013-01-01

To accelerate the decarburization in the Indian power sector, concentrating solar power (CSP) needs to play an important role. CSP technologies have found significant space in the Jawaharlal Nehru National Solar Mission (JNNSM) of the Indian government in which 20,000 MW grid connected solar power projects have been targeted by 2022 with 50% capacity for CSP. In this study a preliminary attempt has been made to assess the potential of CSP generation in the Northwestern (NW) regions of India; which seems a high potential area as it has the highest annual solar radiation in India, favorable meteorological conditions for CSP and large amount of waste land. The potential of CSP systems in NW India is estimated on the basis of a detailed solar radiation and land resource assessment. The energy yield exercise has been carried out for the representative locations using System Advisor Model for four commercially available CSP technologies namely Parabolic Trough Collector (PTC), Central receiver system (CRS), Linear Fresnel Reflector (LFR) and Parabolic Dish System (PDS). The financial viability of CSP systems at different locations in NW India is also analyzed in this study. On the basis of a detailed solar radiation and land resource assessment, the maximum theoretical potential of CSP in NW India is estimated over 2000 GW taking into accounts the viability of different CSP technologies and land suitability criteria. The technical potential is estimated over 1700 GW at an annual direct normal incidence (DNI) over 1800 kW h/m 2 and finally, the economic potential is estimated over 700 GW at an annual DNI over 2000 kW h/m 2 in NW India. It is expected that in near future locations with lower DNI values could also become financially feasible with the development of new technologies, advancement of materials, economy of scale, manufacturing capability along with the enhanced policy measures etc. With an annual DNI over 1600 kW h/m 2 it is possible to exploit over 2000 GW CSP

Preliminary Feasibility Study of a Hybrid Solar and Modular Pumped Storage Hydro System at Biosphere 2

Energy Technology Data Exchange (ETDEWEB)

Lansey, Kevin [Univ. of Arizona, Tucson, AZ (United States); Hortsman, Chris [Univ. of Arizona, Tucson, AZ (United States)

2016-10-01

In this study, the preliminary feasibility of a hybrid solar and modular pumped storage system designed for high energy independence at Biosphere 2 is assessed. The system consists of an array of solar PV panels that generate electricity during the day to power both Biosphere 2 and a pump that sends water through a pipe to a tank at a high elevation. When solar power is not available, the water is released back down the pipe towards a tank at a lower elevation, where it passes through a hydraulic water turbine to generate hydroelectricity to power Biosphere 2. The hybrid system is sized to generate and store enough energy to enable Biosphere 2 to operate without a grid interconnection on an average day.

Experience with solar home systems in developing countries. A review

International Nuclear Information System (INIS)

Nieuwenhout, F.D.J.; Van Dijk, A.L.; Lasschuit, P.E.; Van Roekel, G.M.; Van Dijk, V.A.P.; Hirsch, D.; Arriaza, H.; Hankins, M.; Sharma, B.D.; Wade, H.

2002-01-01

Solar Energy is widely perceived as a promising technology for electricity generation in remote locations in developing countries. It is estimated that 1.3 million solar home systems had been installed by early 2000. An estimated one-third of installed systems were backed by foreign donor support in government programmes and two-thirds supplied by commercial dealers. The estimated growth in the deployment of solar lanterns is less than for SHS. One out of every 100 households that gain access to electricity in developing countries uses solar power. In spite of these successes, doubts have arisen about the effectiveness and suitability of small PV systems for rural development. Many organisational, financial and technical problems appear to present difficulties. A literature survey has been conducted to make an inventory of experience with solar PV applications for households in developing countries. The main finding is that an adequate service infrastructure is required to make projects viable. Household choice in system sizes is often too restricted in donor-funded projects. Smaller systems sold for cash can be a good alternative to credit systems by offering to increased affordability. Gaps in existing knowledge have been identified, which could be overcome by field monitoring programmes. 77 refs

Experimental and Thermoeconomic Analysis of Small-Scale Solar Organic Rankine Cycle (SORC System

Directory of Open Access Journals (Sweden)

Suresh Baral

2015-04-01

Full Text Available A small-scale solar organic Rankine cycle (ORC is a promising renewable energy-driven power generation technology that can be used in the rural areas of developing countries. A prototype was developed and tested for its performance characteristics under a range of solar source temperatures. The solar ORC system power output was calculated based on the thermal and solar collector efficiency. The maximum solar power output was observed in April. The solar ORC unit power output ranged from 0.4 kW to 1.38 kW during the year. The highest power output was obtained when the expander inlet pressure was 13 bar and the solar source temperature was 120 °C. The area of the collector for the investigation was calculated based on the meteorological conditions of Busan City (South Korea. In the second part, economic and thermoeconomic analyses were carried out to determine the cost of energy per kWh from the solar ORC. The selling price of electricity generation was found to be $0.68/kWh and $0.39/kWh for the prototype and low cost solar ORC, respectively. The sensitivity analysis was carried out in order to find the influencing economic parameters for the change in NPV. Finally, the sustainability index was calculated to assess the sustainable development of the solar ORC system.

Long-term energy output estimation for photovoltaic energy systems using synthetic solar irradiation data

International Nuclear Information System (INIS)

Celik, A.N.

2003-01-01

A general methodology is presented to estimate the monthly average daily energy output from photovoltaic energy systems. Energy output is estimated from synthetically generated solar radiation data. The synthetic solar radiation data are generated based on the cumulative frequency distribution of the daily clearness index, given as a function of the monthly clearness index. Two sets of synthetic solar irradiation data are generated: 3- and 4-day months. In the 3-day month, each month is represented by 3 days and in the 4-day month, by 4 days. The 3- and 4-day solar irradiation data are synthetically generated for each month and the corresponding energy outputs are calculated. A total of 8-year long measured hourly solar irradiation data, from five different locations in the world, is used to validate the new model. The monthly energy output values calculated from the synthetic solar irradiation data are compared to those calculated from the measured hour-by-hour data. It is shown that when the measured solar radiation data do not exist for a particular location or reduced data set is advantageous, the energy output from photovoltaic converters could be correctly calculated

Intelligent control of energy-saving power generation system

Energy Technology Data Exchange (ETDEWEB)

Zhang, Zhiyuan; Zhang, Guoqing; Guo, Zhizhong [Harbin Institute of Technology, Harbin (China). Dept. of Electrical Engineering

2013-07-01

Highway power generation system which is environmentally friendly and sustainable provides an innovative method of energy conversion. It is also as a kind of city science and technology innovation, which has the characteristics of environmental protection and sustainable utilization. Making full use of vehicle impact speed control humps, we design a new kind of highway speed control humps combined with solar electric generation system integration. Developing green energy, energy saving and environment protection can be achieved.

Charge Generation Dynamics in Efficient All-Polymer Solar Cells: Influence of Polymer Packing and Morphology.

Science.gov (United States)

Gautam, Bhoj R; Lee, Changyeon; Younts, Robert; Lee, Wonho; Danilov, Evgeny; Kim, Bumjoon J; Gundogdu, Kenan

2015-12-23

All-polymer solar cells exhibit rapid progress in power conversion efficiency (PCE) from 2 to 7.7% over the past few years. While this improvement is primarily attributed to efficient charge transport and balanced mobility between the carriers, not much is known about the charge generation dynamics in these systems. Here we measured exciton relaxation and charge separation dynamics using ultrafast spectroscopy in polymer/polymer blends with different molecular packing and morphology. These measurements indicate that preferential face-on configuration with intermixed nanomorphology increases the charge generation efficiency. In fact, there is a direct quantitative correlation between the free charge population in the ultrafast time scales and the external quantum efficiency, suggesting not only the transport but also charge generation is key for the design of high performance all polymer solar cells.

System approach on solar hydrogen generation and the gas utilization; Taiyo energy ni yoru suiso no seisei oyobi sono riyo system ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Fujii, I; Hirooka, N; Deguchi, Y; Narita, D [Meiji University, Tokyo (Japan)

1997-11-25

An apparatus is developed to establish a system which allows utilization of hydrogen safely and easily, and its applicability to a hydrogen system for domestic purposes is tested. The system converts solar energy by the photovoltaic cell unit into power, which is used to generate hydrogen by electrolysis of water at the hydrogen generator, stores hydrogen in a metal hydride , and sends stored hydrogen to the burner and fuel cell units. It is found that a hydrogen occluding alloy of LaNi4.8Al0.2 stores hydrogen to approximately 80% when cooled to 20 to 25degC, and releases it to 10% when heated to 40degC. The fuel cell uses a solid polymer as the electrolyte. The hydrogen gas burner is a catalytic combustion burner with a Pt catalyst carried by expanded Ni-Al alloy. The optimum distance between the burner and object to be heated is 22mm. High safety and fabrication simplicity are confirmed for use for domestic purposes. The system characteristics will be further investigated. 4 refs., 8 figs.

Optimal Site Selection of Wind-Solar Complementary Power Generation Project for a Large-Scale Plug-In Charging Station

Directory of Open Access Journals (Sweden)

Wenjun Chen

2017-10-01

Full Text Available The wind-solar hybrid power generation project combined with electric vehicle charging stations can effectively reduce the impact on the power system caused by the random charging of electric cars, contribute to the in-situ wind-solar complementary system and reduce the harm arising from its output volatility. In this paper, the site selection index system of a landscape complementary power generation project is established by using the statistical methods and statistical analysis in the literature. Subsequently, using the Analytic Network Process to calculate the index weight, a cloud model was used in combination with preference ranking organization method for enrichment evaluations to transform and sort uncertain language information. Finally, using the results of the decision-making for the location of the Shanghai wind-solar complementary project and by carrying out contrast analysis and sensitivity analysis, the superiority and stability of the decision model constructed in this study was demonstrated.

Solar and atmospheric neutrinos in three generations with a magnetic moment

International Nuclear Information System (INIS)

Pulido, J.; Tao, Z.

1995-01-01

A solution to the solar and atomospheric neutrino problems in three generations in the joint context of matter oscillations and the magnetic moment is investigated. An appropriate rotation of the evolution Hamiltonian reduces the three generation case to a two generation one. A convenient background for such a scenario with small neutrino masses and large magnetic moments is given by the Zee-type models, in which the mass generation mechanism leads to a pair of separate orders of magnitude for the mass square differences between neutrino species. We obtain a ratio var-epsilon congruent 10 -2 --10 -3 between these orders of magnitude, so that one of them [(0.3--3)x10 -2 eV 2 ] is suitable for the atmospheric neutrino solution and the other (∼10 -5 eV 2 ) for the solar neutrino solution. The magnetic moment leads to a decrease of the survival probability with solar neutrino energy. Such a decrease is consistent with the experimental situation

Analysis of a novel solar energy-powered Rankine cycle for combined power and heat generation using supercritical carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Zhang, X.R.; Yamaguchi, H.; Uneno, D. [Department of Mechanical Engineering, Doshisha University, Kyoto 630-0321 (Japan); Fujima, K. [Mayekawa MFG Co., Ltd., 2000 Tatsuzawa Moriya-city, Ibaraki-Pref. 302-0118 (Japan); Enomoto, M. [Showa Denko K. K., 1-480, Inuzuka, Oyama-city, Tochigi 323-8679 (Japan); Sawada, N. [Showa Tansan Co., Ltd., 7-1, Ogimachi, Kawasaki-Ku, Kawasaki-city, Kanagawa 210-0867 (Japan)

2006-10-15

Theoretical analysis of a solar energy-powered Rankine thermodynamic cycle utilizing an innovative new concept, which uses supercritical carbon dioxide as a working fluid, is presented. In this system, a truly 'natural' working fluid, carbon dioxide, is utilized to generate firstly electricity power and secondly high-grade heat power and low-grade heat power. The uniqueness of the system is in the way in which both solar energy and carbon dioxide, available in abundant quantities in all parts of the world, are simultaneously used to build up a thermodynamic cycle and has the potential to reduce energy shortage and greatly reduce carbon dioxide emissions and global warming, offering environmental and personal safety simultaneously. The system consists of an evacuated solar collector system, a power-generating turbine, a high-grade heat recovery system, a low-grade heat recovery system and a feed pump. The performances of this CO{sub 2}-based Rankine cycle were theoretically investigated and the effects of various design conditions, namely, solar radiation, solar collector area and CO{sub 2} flow rate, were studied. Numerical simulations show that the proposed system may have electricity power efficiency and heat power efficiency as high as 11.4% and 36.2%, respectively. It is also found that the cycle performances strongly depend on climate conditions. Also the electricity power and heat power outputs increase with the collector area and CO{sub 2} flow rate. The estimated COP{sub power} and COP{sub heat} increase with the CO{sub 2} flow rate, but decrease with the collector area. The CO{sub 2}-based cycle can be optimized to provide maximum power, maximum heat recovery or a combination of both. The results suggest the potential of this new concept for applications to electricity power and heat power generation. (author)