• 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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• 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/$m^2$.

• 조명전기설비학회논문지
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• 제24권1호
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• pp.19-27
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• 2010

천공커버법칙은 기상청에서 제공하는 전운량을 활용하여 천공 상태를 결정할 수 있으며, HCI(Hourly Clearness Index) 방법은 측정된 태양의 수평 일사량을 이용하여 천공 상태를 결정한다. HCI 방법에는 Erbs et al. 방법(1982)과 Orgill and Holland 방법(1977) 등이 있으나, 이와 같은 기존의 방법은 약 30여 년전에 수립된 것으로 현재의 대기 상황과 다소 다르기 때문에 실제 전운량에 의한 천공 상태와 차이를 보인다. 본 연구의 목적은 HCI에 의한 천공 구분 방법을 개선하고자 하는데 있으며, 이에 기상청 데이터를 이용한 천공커버법칙에 의한 천공상태와 측정된 수평 일사량을 이용한 HCI의 천공상태를 비교 분석하여 기존 HCI 방법의 시간별 보정 방법을 제안하였다. 그 결과, 보정된 HCI 방법이 기존의 HCI 방법에 비해 천공별 유사성이 다소 향상되었다.