• 대한전기학회:학술대회논문집
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• 대한전기학회 2011년도 제42회 하계학술대회
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• pp.888-889
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• 2011

As new one of superconducting power supplies, we proposed an HTS flux pump utilized a solar energy system. As an eternal electric energy can be converted by the solar system, the solar energy system is promisingly applied as an energy source in the power applications. A solar energy system is comprised of solar panel, photo-voltaic (PV) controller, converter and battery. The HTS flux pump consists of an electromagnet, two thermal heaters and a Bi-2223 magnet. In this paper, we describe the possibility the fusion technology between superconducting power supply and solar energy system. As a fundamental step, the fabrication, structure and experimental results are explained.

• 한국태양에너지학회 논문집
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• 제32권2호
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• pp.35-41
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• 2012

Knowledge of the solar radiation components and classified wavelength data are essential for modeling many solar photovoltaic systems. This is particularly the case for applications that concentrate the incident energy to attain high photo-dynamic efficiency achievable only at the higher intensities. In order to estimate the performance of concentrating PV systems, it is necessary to know the intensity of the beam radiation, as only this components can be concentrated, and The new PV cell can generate electricity from ultraviolet and infrared light as well as visible light. The Korea Institute of Energy Research(KIER) has began collecting solar radiation components data since January, 1988, and solar radiation classified wavelength data since November, 2008. KIER's solar radiation components and classified wavelength data will be extensively used by concentrating PV system users or designers as well as by research institutes. It is essential to utilize the solar radiation data as application and development of solar energy system increase. Consider able efforts have been made constructing a standard data base system from measure data.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
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• pp.313-318
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• 2012

In the present study, the preliminary study on a small solar-powered RC airplane are performed for the development of a long-endurance solar-powered UAV. Solar energy enables the solar-powered UAV to fly longer or eternally. The solar-powered UAV transfers the solar energy to electric energy and this energy is used for the flight and the battery charge. To increase the flying time, the efficiency of the solar-cell power system must be increased and the required power for flight must be minimized. Hence, the system integration including solar cell and controller, the power system design, and the aerodynamic and structural designs of the UAV is very important. The present study have performed the design, manufacture, and flight test of the small solar-powered UAV for the preliminary study of the long-endurance solar-powered UAV. From this study, the system integration technology of the solar-powered UAV design is established, and the possibility and the issue points for the development of the long-endurance solar-powered UAV are discussed.

• 한국태양에너지학회 논문집
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• 제38권5호
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• pp.37-47
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• 2018

The heating performance of a solar thermal seasonal storage system applied to a glass greenhouse was analyzed numerically. For this study, the gardening 16th zucchini greenhouse of Jeollanam-do agricultural research & extension services was selected. And, the heating load of the glass greenhouse selected was 576 GJ. BTES (Borehole Thermal Energy Storage) was considered as a seasonal storage, which is relatively economical. The TRNSYS was used to predict and analyze the dynamic performance of the solar thermal system. Numerical simulation was performed by modeling the solar thermal seasonal storage system consisting of flat plate solar collector, BTES system, short-term storage tank, boiler, heat exchanger, pump, controller. As a result of the analysis, the energy of 928 GJ from the flat plate solar collector was stored into BTES system and 393 GJ of energy from BTES system was extracted during heating period, so that it was confirmed that the thermal efficiency of BTES system was 42% in 5th year. Also since the heat supplied from the auxiliary boiler was 87 GJ in 5th year, the total annual heating demand was confirmed to be mostly satisfied by the proposed system.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.95-104
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• 2013

This study set out to devise an optimized system to take into account life cycle cost(LCC) and ton of carbon dioxide($TCO_2$) by applying the weighted coefficient method(WCM) to "public-purpose" facility buildings according to the mandatory 5% and 11% of new renewable energy in total construction costs and anticipated energy consumption, respectively, based on the changes of the public obligation system. (1) System installation capacity is applied within the same new renewable energy facility investment according to the mandatory 5% of new renewable energy in total construction costs. Both LCC and $TCO_2$ recorded in the descending order of geothermal, solar, and photovoltaic energy. The geothermal energy systems tended to exhibit an excellent performance with the increasing installation capacity percentage. (2) Optimal systems include the geothermal energy(100%) system in the category of single systems, the solar energy(12%)+geothermal energy(88%) system in the category of 2-combined systems, and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system and the photovoltaic energy(12%)+solar energy(25%)+geothermal energy(63%) system in the category of 3-combined systems. (3) LCC was the highest in the descending order of photovoltaic, geothermal and solar energy due to the influences of each energy source's correction coefficient according to the mandatory 11% of new renewable energy in anticipated energy consumption. The greater installation capacity percentage photovoltaic energy had, the more excellent tendency was observed. $TCO_2$ recorded in the descending order of geothermal, photovoltaic and solar energy with the decreasing installation capacity of photovoltaic energy. The greater installation capacity percentage a geothermal energy system had, the more excellent tendency it demonstrated. (4) Optimal systems include the geothermal energy(100%) system in the category of single systems, the photovoltaic energy(62%)+geothermal energy(38%) system in the category of 2-combined systems, and the photovoltaic energy(50%)+solar energy(12%)+geothermal energy(38%) system and the photovoltaic energy(12%)+solar energy(12%)+geothermal energy(76%) system in the category of 3-combined systems.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.425-429
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• 1990

In order to spread the practical utilization of solar energy, it depends upon how we can increase the efficiency of solar energy conversion system. This paper describes the method for calculating of optimal passive elements values in Maximum Solar Energy Tracking System. And experimental results with those calculated values are presented.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.21-24
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• 2008

In this paper, we introduce the status of concentration photovoltaic system. Currently, crystalline silicon solar has 90% of total solar market. But in a few years, the concentration solar system is expected to be main one because cost increasement of silicon material is not stabilized unit now. At 2012, it will take 5% of the whole solar market. Less expensive, material requirement and high system efficiency give high driving force for intensive research on concentration system. It is time for us to initiate the basic study and evaluate the long term stability compared to crystalline silicon system. The detail discussion will be shown in the following paper.

• 한국태양에너지학회 논문집
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• 제34권5호
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• pp.109-115
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• 2014

The supply rate of renewable energy has been increasing under the influence of an energy scarcity. Government has supported the use of renewable energy by government subsidies. The operation of renewable may not been operating appropriately, although increasing the use of renewable energy. We found out some problems of the operation of renewable energy and offered some improvements. This research proposes the efficient operation method for the solar thermal system, and proposed operation method was compared and evaluated with existing operation strategy after selecting one building installed solar thermal system. Recently, the interest to renewable energy has increased because of the environmental issues and energy crisis. However the utilization of the renewable energy system is low because of the use of renewable energy system and existing renewable energy system independently, although supply rate of renewable system is increasing. Especially, in the case of solar thermal system heating load is not responsible for the load of hot water supply in many cases. Therefore, suggesting efficient operation plans and evaluations of the energy consumption and efficiency of a solar thermal system is needed.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.214-219
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• 2008

This study is describes thermal performance of solar cooling and hot water for demonstration system with ETSC(Evacuated tubular solar collector) installed at Seo-gu culture center of Kwanju. Control condition for solar cooling and hot water system is changed by connection of auxiliary heater. Demonstration system was connected to central air conditioning system. Demonstration system was operated by two types. First type(A) was operated to cooling and hot water supply in that order. Second type(B) was operated to hot water supply and cooling in that order. As a result. it was indicated that the total solar energy consumption of (A) was 799 MJ and the solar energy consumption rate for the cooling and hot water supply was 70% and 30% respectively. Total solar energy consumption of (b) was 898 MJ and the solar energy consumption rate for the cooling and hot water supply was 31% and 69% respectively.

• 한국태양에너지학회 논문집
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• 제33권6호
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• pp.98-104
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• 2013

At the moment, in Korea, over 90% of energy resources depend on imports, and nearly 60% of electric energy is produced using fossil fuel. Therefore, the government adopted the Climatic Change Convention and has implemented the RPS system since 2012 to actively cope with the dependence on imported energy, and to grow and expand the new renewable energy industry. This study examined the performance results of mandatory supply of solar photovoltaic energy and non-solar photovoltaic energy assigned to providers and the present state after implementation of the RPS system. As a result, the achievement rate in 2012 was 64.7%. Especially, solar photovoltaic energy showed a high achievement rate of 95.7%, whereas non-solar photovoltaic energy showed a low achievement rate of 63.3% due to several problems and was highly dependent on the government. In 2013, the burden of each provider has increased due to more mandatory supply and addition of unfulfilled supply of 2012, and the separate mandatory supply of solar photovoltaic energy established for protection of the solar photovoltaic market is restricting investment. Therefore, there is a need to assign mandatory supply in consideration of the available amount of each new renewable energy.