• Journal of the Korean Solar Energy Society
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• v.26 no.1
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• pp.7-12
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• 2006

The dish type solar thermal concentrating system can collect the solar energy above $800^{\circ}C$. It has a concentration ratio of 800 and total reflector area of $49m^2$. To operate solar receivers at high temperature, the optimum aperture size is obtained from a comparison between maximizing absorbed energy and minimizing thermal losses. The system efficiency is defined as the absorbed energy by working fluid in receiver divided by the energy coming from the concentrator. We find that system efficiency is stable in case of flow rate of above 6lpm. The system efficiency are 64.9% and 65.7% in flow rate of 6lpm and 8lpm, respectively. The thermal performance showed that the maximum efficiency and the factor of thermal loss in flow rate of 8lpm are 68% and 0.0508.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.580-583
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• 2006

A small-scale solar concentrating system was developed and demonstrated for supplying process heat required in solar thermo chemical reaction. The concentration system consists of a heliostat equipped with a solar tracking device and a dish concentrator. From the initial thermal test of the concentrating system it was found that the system works very well with around 500-600 concentration ratio capable of supplying about 3kW therml energy to the reactor. Once the concentration system was turned on, the reactor temperature rapidly increased over $1,000^{\circ}C$ and could be maintained high enough for solar chemical reaction.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.174-177
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• 2008

The proceeding of the $14^{th}$ biennial concentrating solar power SolarPACES symposium was closely reviewed and summarized to have an overview on up-to-date concentrated solar thermal technologies. A number of studies covering parabolic trough concentrating system, central receiver technology, solar fuels, dish and others were presented in the symposium which was held in Las Vegas, USA, from 4 to 7, 2008. Based on this overview a brief summary of technology trend and prospects were added in the paper.

• Solar Energy
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• v.6 no.2
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• pp.3-14
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• 1986

It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolique concentrating solar collector (M.C.P.C.S.C) was designed, which has several rows of parabolique reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The thermal performance of the M.C.P.C.S.C. newly designed in this study was analysed theoretically and experimentally. The results are summarized as follows: 1) prediction equation for outlet temperature, $T_o$, of heat transfer fluid and for the thermal efficiency, ${\eta}$, of the collector were derived as; o $$T_o=[C+B1_n(\frac{I_c(t)}{pv^3})]T_i$$ o $${\eta}=\frac{A}{A_c}\dot{m}[(C-1)+B1_n(E{\cdot}di^6\frac{I_c(t)}{\dot{m}^3})]\frac{T_i}{I_c(t)}$$ 2) When the insolation on the tilted solar collector surface, $I_c$, was $900-950W/m^2$ and the heat transfer fluid was not circulated in tubular absorber, the maximum temperature on the absorber surface was $100-118^{\circ}C$, this result suggested that the heat transfer fluid could be heated up to $98-116^{\circ}C$. The maximum temperature on the absorber surface was decreased with the increase of the collector shape factor, $L_p/L_w$ 3) There was a good agreement between the experimental and theoretical value of solar collector efficiency, ${\eta}$, which was proportional to the collector shape factor, $L_p/L_w$ 4) It is desirable to continue the study on the relationship between the collector shape factor, $L_p/L_w$, and the thermal efficiency of solar collector.

• 전기의세계
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• v.30 no.10
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• pp.655-661
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• 1981

The concentrating solar module with high concentration ratio(320)has been studied.in this paper. The solar module was composed of the EMVJ solar cell, (Fresnel Lens-DCPC)concentrator and heat sink, and was measured by using the PASTF system. The experimental result and the result analysis for the individual item of the module were as f ollows; (1) The conversion efficiency of the module was 8.3%. (2) The optical efficiency of the concentrator was 46.5% (DCPC; 84.8%, Fresnel Lens; 54.8%). (3) The thermal loss of the solar cell was 4.9%. And methods for the further improvement of the concentrating solar module efficiency have been suggested.

• Solar Energy
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• v.6 no.1
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• pp.24-30
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• 1986

A concentrating solar collector of parabolic-cylindrical type is designed and constructed to provide a heat source of higher temperature for drying processes. Usually collectors of concentrating type require such peripheral auxiliary units as solar tracking system, heat medium circulation pump and temperature controller. However in this study, for simplification's sake in the maintenance of a collector system, it is intended to design a concentrating collector system which does not furnish these auxiliary units by adapting natural circulation system instead of foced circulation and by adjusting collector system to solar altitude manually and periodically. And based on the experimental data, a conceptual design for a heat sources of 50KWt thermal output is presented and discussed.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.246-249
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• 2011

SolarPACES is an international cooperative network bringing together teams of national exports from around the world to focus on the development and marketing of concentrating solar power systems (also known as solar thermal power systems). It is one of a number of collaborative programs, called Implementing Agreements, managed under the umbrella of the International Energy Agency to help find solutions to worldwide energy problems. Technology development is at the core of the work of SolarPACES. Member countries work together on activities aimed at solving the wide range of technical problems associated with commercialization of concentrating solar technology, including large-scale system tests and the development of advanced technologies, components, instrumentation, and systems analysis techniques. In addition to technology development, market development and building of awareness of the potential of concentrating solar technologies are key elements of the SolarPACES program The Implementing Agreement specifies broad "Tasks," or thematic areas of work SolarPACES currently has three ongoing tasks, focusing on concentrating solar electric power systems (Task I), solar chemistry research (Task II), and solar technology and applications (Task III). An Operating Agent, nominated by the ExCo, is responsible for overseeing the work of each task Each task maintains a detailed program of work that defines all task activities, including their objectives, participants, plans, and budgets. In addition to technical reports of the activities and their participants, accomplishments and progress are summarized in the SolarPACES annual report. Many SolarPACES activities involve close cooperation among member countries (either through sharing of task activities or, occasionally, cost-sharing), although some cooperation is limited to sharing of information and results with other participants. In this paper, structure, works, and members of SolarPACES and Korean activies in the SolarPACES are introduced.

• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.320-323
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• 2011

SolarPACES is an international cooperative network bringing together teams of national experts from around the world to focus on the development and marketing of concentrating solar power systems (also known as solar thermal power systems). It is one of a number of collaborative programs, called Implementing Agreements, managed under the umbrella of the International Energy Agency to help find solutions to worldwide energy problems. Technology development is at the core of the work of Solar PACES. Member countries work together on activities aimed at solving the wide range of technical problems associated with commercialization of concentrating solar technology, including large-scale system tests and the development of advanced technologies, components, instrumentation, and systems analysis techniques. In addition to technology development, market development and building of awareness of the potential of concentrating solar technologies are key elements of the Solar PACES program. The Implementing Agreement specifies broad "Tasks," or thematic areas of work. SolarPACES currently has three ongoing tasks, focusing on concentrating solar electric power systems (Task I), solar chemistry research (Task II), and solar technology and applications (Task III). An Operating Agent, nominated by the ExCo, is responsible for overseeing the work of each task. Each task maintains a detailed program of work that defines all task activities, including their objectives, participants, plans, and budgets. In addition to technical reports of the activities and their participants, accomplishments and progress are summarized in the SolarPACES annual report. Many SolarPACES activities involve close cooperation among member countries (either through sharing of task activities or, occasionally, cost-sharing), although some cooperation is limited to sharing of information and results with other participants. In this paper, structure, works, and members of SolarPACES and Korean activies in the SolarPACES are introduced.

• Journal of the Korean Solar Energy Society
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• v.29 no.3
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• pp.12-18
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• 2009

The Knowledge of the solar radiation components are essential for modeling many solar energy systems. This is particularly the case for applications that concentrate the incident energy to attain high thermodynamic efficiency achievable only at the higher temperatures. In order to estimate the performance of concentrating thermal systems, it is necessary to know the intensity of the beam radiation, as only this component can be concentrated. The Korea Institute of Energy Research(KIER) has began collecting solar radiation component data since January, 2002. KIER's component data will be extensively used by concentrating system users or designers as well as by research institutes. The theoretical analysis of solar radiation as a component has compared with the experimental data obtained by the KIER station. The Result of simulation analysis shows that the annual-average daily diffuse radiation on the horizontal surface is $1,457cal/m^2$ and daily direct radiation on the horizontal surface is $1,632cal/m^2$ for all over the 16 areas in Korea.

• Journal of Biosystems Engineering
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• v.10 no.1
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• pp.54-68
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• 1985

It is desirable to collect the solar thermal energy at relatively high temperature in order to minimize the size of thermal storage system and to enlarge the scope of solar thermal energy utilization. So far the concentrating solar collector has been developed to collect solar thermal energy at relatively high temperature, but it has some difficulties in maintaining the volumetric body of solar collector for long term utilization. On the other hand, the flat-plate solar collector has been developed to collect the solar thermal energy at low temperature, and it has advantages in maintaining the system for long term utilization, since it's thickness is thin and not volumetric. In this study, to develop a solar collector that has both advantages of collecting solar thermal energy at high temperature and fixing conveniently the collector system for long term period, a cylindrical parabolic concentrating solar collector was designed, which has two rows of parabolic reflectors and thin thickness such as the flat-plate solar collector, maintaining the optical form of concentrating solar collector. The characteristics of the concentrating parabolic solar collector newly designed was analysed and the results are summarized as follows; 1. The temperature of the air enclosed in solar collector was all the same as $50^{\circ}C$ in both cases of the open and closed loop, and when the heat transfer fluid was not circulated in tubular absorber, the maximum surface temperature of the absorber was $118-120^{\circ}C$, this results suggested that the heat transfer fluid could be heated up to $118^{\circ}C$. 2. In case of longitudinal installation of the solar collector, the temperature difference of heat transfer fluid between inlet and outlet was $4^{\circ}-6^{\circ}C$ at the flow rate of $110-130{\ell}/hr$, and the collected solar energy per unit area of collector was $300-465W/m^2$. 3. The collected solar energy per unit area for 7 hours was 1960 Kcal/$m^2$ for the open loop and 220 Kcal/$m^2$ for the closed loop. Therefore it is necessary to combine the open and closed loop of solar collectors to improve the thermal efficiency of solar collector. 4. The thermal efficiency of the solar collector (C.P.C.S.C.) was proportional to the density of solar radiation, indicating the maximum thermal efficiency ${\eta}_{max}=58%$ with longitudinal installation and ${\eta}_{max}=45%$ with lateral installation. 5. The thermal efficiency of the solar collector (C.P.C.S.C.) was increased in accordance with the increase of flow rate of heat transfer fluid, presenting the flow rate of $110{\ell}/hr$ was the value of turning point of the increasing rate of the collector efficiency, therefore the flow rate of $110{\ell}/hr$ was considered as optimum value for the test of the solar collector (C.P.C.S.C.) performance when the heat transfer fluid is a liquid. 6. In both cases of longitudinal and lateral installation of the solar collector (C.P.C.S.C.), the thermal efficiency was decreased linearly with an increase in the value of the term ($T_m-T_a$)/Ic and the increasing rate of the thermal efficiency was not effected by the installation method of solar collector.