• 한국태양에너지학회 논문집
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• 제26권1호
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• pp.13-19
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• 2006

The efficiency of building-integrated photovoltaic(BIPV) system is mainly determined by solar radiation and the temperature of PV modules. The performance of BIPV systems is reported to be different from that of conventional PV systems installed in the open-air. This paper presents the relationship of solar radiation and electricity generation from a 2kWp roof-integrated PV system that is applied as building elements on an experimental house, and the energy saving effect of the BIPV system for a typical house. For the performance evaluation of the BIPV system, it produced a regression equation with measured data for winter days. The regression equation showed that a comparison of the measured electricity generation and the predicted electricity generation of the BIPV system were meaningful. It showed that an annual electricity generation of the system appeared to cover around 52% of an annual electricity consumption of a typical domestic house with the floor area of $96m^2$.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.364-369
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• 2011

Recently, the cases of BIPV(Building-integrated Photovoltaic) have been increased with interest in renewable energy application for buildings. PV System in building can perform a variety of roles as an energy supplier, exterior materials, aesthetic element and etc. To apply PV modules in buildings, various factors should be considered, such as the installation angle and orientation of PV module, shading, and temperature. The temperature of PV modules that are attached to building surfaces especially is one of the most important factors, as it affects both the electrical efficiency of a PV module and the energy load in a building. BIPV modules designed as finished material for spandrels are presented in this paper. The purpose of this study is to analysis on the thermal performance characteristics of BIPV modules. This study dealt with different types of BIPV modules depending on the backside material, such as clear glass and backsheet. The analysis of monitoring data shows that the PV module temperature was closely related to the solar radiation on the BIPV module surface, and the BIPV used at the backside also had an effect on the PV module temperature that in turn determines its thermal performance.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.87-92
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• 2011

The heat from PV modules should be removed for better electrical performance, and can be converted into useful thermal energy. A photovoltaic-thermal(PVT)module is a combination of PV module with a solar thermal collector which forms one device that converts solar radiation into electricity and heat simultaneously. The performance of the PV/Thermal combined collector module is directly influenced by solar radiation that also has an effect on PV module temperature. It is also has believe that the energy performance of PV/T collector is related to absorber design as well as PV module temperature. The existing study has been paid to the PV/Thermal combined collector module with circle tube absorbers. The aim of this study is to analyze the experimental performance of the PV/Thermal combined collector rectangular tube absorbers according to solar radiation. The experimental result show that the average thermal and electrical efficiencies of the PVT collector were 43% and14.81% respectively. Solar radiation is one of the most influential factors to determine the energy performance of PVT collector, but from a certain level of solar radiation the PVT collector receives on, its efficiencies began to decrease.

• 태양에너지
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• 제10권2호
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• pp.10-17
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• 1990

건물의 사양으로부터 시뮬레이션에 의해 열성능을 추출하는 기법과 실측 데이타로 부터 연역적인 방법에 의해 열성능을 추출하는 기법을 연합시켜 단기간의 측정에 의해 건물의 열성능을 간단하고 정확하게 결정할 수 있는 기법을 Test cell에 적용하였다. 실험과정 및 자료분석은 PSTAR 기법에 따라 수행했다. 각 측정기간은 3일간으로 비거주 상태에서 측정했으며, 실내온도, 외기온, 일사량, 공급열량, 풍속, 상대습도등의 자료를 측정하여 건물의 사양에 의한 시뮬레이션 모델의 재표준화에 사용했다. 아래의 3개 주요계수들이 본 분석에 의해 얻어졌다. 1) 건물 열손실계수 : BLC(표면전도율+침기에 의한 전도율); 2) 유효 건물열용량; 3) 유효 태양열 획득량. 그리고 재표준화된 식으로부터 예측된 값과 건물의 사양으로 시뮬레이션에 의해 예측된 값과 측정된 값과의 비교를 통해 재표준화된 식이 실제건물의 열성능을 잘 묘사함을 알 수 있었다. 장기간의 외삽으로 기후 자료를 이용하여 표준 쾌적도를 유지하기 위해 필요한 에너지를 계산했다.

• 한국태양에너지학회 논문집
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• 제30권6호
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• pp.118-124
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• 2010

In order to develop commercial model of 10kW dish-Stirling solar thermal power system, modification for the exiting facility was taken for a year as a Leading Project in KIER. During the project, solar tracking system, control and monitoring system and high durability reflector were developed and long term operation were performed. The solar tracking system was tested for four months to investigate the degree of precision and adapted to the control system for an actual operation from October in 2009. The sun tracking accuracy of ${\pm}4$ mrad using modified control system was obtained and the system operated successfully during the experimental period. The monitoring system displays engine pressure, electric generation amounts, generator RPM, receiver temperatures, and etc. from Stirling engine and weather data of Direct Normal Irradiation, Horizontal Global Insolation, wind speed & direction, and atmosphere temperature from weather station. According to the operating results in a clear sky day, electric power of 6,890 W was generated at the DNI value of 850 W/$m^2$ and the averaged solar-to-electricity efficiency during a whole day reached to 18.99%. From the overall operating results, linear power generation trend could be observed with increasing DNI value. The solar-to-electricity efficiency achieved to 19% around the DNI value of 700 W/$m^2$ and increased to 20% when the DNI value goes up to 900 W/$m^2$.

• 한국태양에너지학회 논문집
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• 제27권1호
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• pp.55-61
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• 2007

This paper describes the procedure and calculation results of basic design and transient variation of performance of 1 MWe large scale solar thermal power plant (STPP) by using the commercial software of THERMOFLEX and TRNSYS, respectively. In order to simulate the transient variation of STPP, the results of basic design are necessary. The design standard of the STPP is 1 MWe generation with solar only at high DNI condition and then 0.6 MWe output power for 1 hour using stored energy when the DNI becomes lower unable to operate normally. The results of basic design show the important design data of flow rates, water/steam conditions at each equipments and the estimated efficiency of STPP. In addition, dynamic simulation results of STPP are predicted and plotted for one year and three different days weather data of Daejeon.

• 태양에너지
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• 제11권1호
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• pp.27-40
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• 1991

에너지 소비 구조의 개선을 목적으로 한 자연에너지 이용시스템의 도입이 전력 계통의 계획 운용에 미치는 영향을 다목적 최적화 방법을 이용하여 평가하는 방법이 논하여 지고 있다. 본 연구에서는 시험 제작한 태양열과 풍력 에너지를 주체로하는 자연에너지 복합 이용시스템이 특정 지역에 복수 도입되어 지는 경우 전력 통계 운용에 의한 경제성, 안정성, 환경에 대한 영향 평가 방법을 검토하였다. 연구 방법은 대상 지역의 일사 분포와 풍속 분포에 의해서 취득 가능한 에너지를 산정하여 전력 계통 부하의 형상에 미치는 영향을 구하였고, 다음에는 대상 기간에 의한 최적 발전 배분을 결정하여 경제성, 안정성, 환경 지표 등의 평가를 하였다. 지금까지는 자연에너지 이용시스템의 도입에 대하여 경제적 측면만 논의되었지만, 본 연구에서 제한된 방법에 의해 안정성과 환경 보전의 영향을 고려한 평가 방법도 가능하다는 것을 나타내었다.

• 한국태양에너지학회 논문집
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• 제28권4호
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• pp.17-24
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• 2008

Estimation of typical solar radiation is very important for the calculations concerning many solar applications. But solar radiation measurements are not easily available because of the expensive measuring equipment and techniques required. Accordingly, for regions where no solar radiation is measured, solar radiation need to be estimated using other meteorological data. However, currently in Korea, there is no study on how to do this. In this paper, the global radiation of the six major cities in South Korea where the global radiation is measured using comparatively simple CRM model was calculated compared and analyzed. The comparison between the original coefficient and the site-fitted coefficient for these cities are as follows. Differences between the site-fitted coefficient and the original coefficient for six cities are small. Except for Gwangju, both calculations show strong correlation. In case of Seoul, the $R^2$(coefficient of determination) were 0.747 and 0.749. In case of Busan and Daegu the figures were 0.817, 0.819 and 0.820, 0.821 respectively. For Gwangju, these were 0.618 and 0.622, Thus, the site-fitted coefficients were slightly higher for these four cities. On the other hand, Daejeon and Incheon was reported 0.773, 0.772 and 0.785, 0.783, respectively.

• 한국태양에너지학회 논문집
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• 제40권3호
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• pp.43-52
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• 2020

By blocking irradiance, shadows cast by high-rise buildings in urban areas can reduce the power generation efficiency of PV panels installed on low-rise buildings. As the conventionally installed PV panel is not suitable for the urban environment, which is unfavorable for power generating, a more radical solution is required. This study aims to help solve this problem by estimating the optimal PV panel angle. Using the proposed method, the optimal PV angle was calculated by considering shadows that could be cast by nearby buildings throughout the year, and the correlation between solar shading and elevation angle was discovered based on the calculated data.

• 한국태양에너지학회 논문집
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• 제39권2호
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• pp.71-80
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• 2019

Daily ahead forecast is necessary for the electricity balance between load and supply due to the variability renewable energy. Numerical weather prediction is usually employed to produce the solar irradiance as well as electric power forecast for more than 12 hours forecast horizon. UM-LDAPS model is the numerical weather prediction operated by Korea Meteorological Administration and it generates the 36 hours forecast of hourly total irradiance 4 times a day. This study attempts to evaluate the model performance against the in situ measurements at 37 ground stations from January to May, 2013. Relative mean bias error, mean absolute error and root mean square error of hourly total irradiance are averaged over all ground stations as being 8.2%, 21.2% and 29.6%, respectively. The behavior of mean bias error appears to be different; positively largest in Chupoongnyeong station but negatively largest in Daegu station. The distinct contrast might be attributed to the limitation of microphysics parameterization for thick and thin clouds in the model.