• 한국태양에너지학회 논문집
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• 제30권3호
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• pp.1-9
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• 2010

Since the horizontal global radiation and cloud cover are a main factor for designing any solar photovoltaic system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982. 12~2008. 12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61\;kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.124-129
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• 2011

Since the horizontal global radiation and cloud cover are a main factor for designing any solar energy system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and cloud cover in Korea. The data utilized in the investigation consist of horizontal global radiation and cloud cover collected for 27 years(1982.12~2008.12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is $3.61kWh/m^2$ and the annual-average daily cloud cover is 5.1 in Korea. We also constructed the contour map of cloud cover in Korea by interpolating actually measured data across the country.

• 한국태양에너지학회 논문집
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• 제31권3호
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• pp.48-56
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• 2011

Since the horizontal global radiation and hours of bright sunshine are a main factor for designing photovoltaic system, it is necessary to evaluate its characteristics all over the country. The work presented here are the investigation of horizontal global radiation and hours of bright sunshine in Korea. The data utilized in the investigation consist of horizontal global radiation and hours of bright sunshine collected for 28years(1982.12~2009.12) at measuring stations across the country. The analysis shows that the annual-average daily horizontal global radiation is3.61kWh/m2 and the annual-average daily hours of bright sunshineis 5.1 Hrs in Korea. We also constructed the contour map of hours of horizontal global radiation and hours of bright sunshine in Korea by interpolating actually measured data across the country.

• 대한원격탐사학회지
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• 제29권1호
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• pp.151-160
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• 2013

근래 들어 위성영상 기반의 한반도 지역 일사량 추정 연구가 활발히 진행되고 있으나 대부분의 연구들은 외국 위성영상을 이용하고 있다. 이에 본 연구에서는 국내 정지궤도 위성영상을 활용하여 한반도 지역의 일사량을 추정하는 것을 목적으로 한다. 입력데이터로는 국내최초의 정지궤도 위성인 천리안 기상영상기의 레벨1 데이터 및 레벨2 구름 영상, 그리고 미국 NASA의 OMI 영상을 이용하고, 물리모델식은 동아시아지역 일사량 추정에 보다 적합하다고 알려진 Kawamura 모델식을 적용한다. 2011년 5월~2012년 4월에 이르는 기간의 15분 간격 데이터를 이용하여 일일 수평면 전일사량을 추정하였으며, 이를 대한민국의 18개지점의 관측소 실측치와 비교하였다. 일일 일사량 추정값과 관측값 간의 $R^2$값은 0.86로서 높은 상관성을 나타냈으며, 월평균 일사량의 오차는 대부분의 지점에서 ${\pm}15%$ 이내였고 연평균 수평면 전일사량의 오차는 서울을 제외하면 약 -5~+5%의 분포를 보였다. 본 연구결과를 통해 한반도 지역의 일사량을 추정하는데 있어 천리안 기상영상기 영상이 활용 될 수 있음을 확인하였다.

• 한국태양에너지학회 논문집
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• 제30권5호
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• pp.25-31
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• 2010

A Precision Spectral Pyranometer (PSP) is mainly used as a reference to calibrate other pyranometers due to its high accuracy and sensitivity in response to the spectrum wavelength range of 0.285 ${\mu}$ to 2.8 ${\mu}$, while the sensitivity of photovoltaic-type Li-Cor pyranometer is limited within a certain spectral range from 0.4 ${\mu}$ to 1.1 ${\mu}$. In this study, two Eppley PSPs($PSP_1$ and $PSP_2$) were first compared to the calibrated Eppley PSPs from National Renewable Energy Laboratory (NREL), resulting in two linear correction factors based on the comparison between the logger output (V) from the test PSP and the solar radiation (W/m2) from the NREL PSP. The Li-Cor pyranometer used in this study was then corrected based on the comparison of measured solar radiation ($W/m^2$) from the corrected $PSP_1$ and the Li-Cor pyranometer. In addition, instrument scale corrections were also performed for the PSPs and the Li-Cor from the transmitter to the data logger. From the comparisons, a linear correction factor (1.0214) with R=0.9998 was developed for the scale correction between$PSP_1$ and $PSP_2$, while the Li-Cor pyranometer has a scale(1.0597) and offset (32.046) with R=0.9998 against$PSP_1$. As a result, it was identified that there were good agreements within ${\pm}$ 10 W/ $m^2$ between Eppley $PSP_1$ vs. $PSP_2$ solar radiation and within ${\pm}$ 20 W/$m^2$ between$PSP_1$ vs Li-Cor solar radiation after the empirical scale corrections developed in this study.

• 한국태양에너지학회 논문집
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• 제34권1호
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• pp.39-47
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• 2014

Solar applications analysis and building energy performance depend on the quality of the solar resource data available. Unfortunately, most of the weather stations do not measure solar radiation data in Korea, as a reason many researchers have studied different solar radiation estimation models and suggested to apply them to various locations in Korea. In addition, they also studied the impact of hourly global solar radiation on energy performance of an office building by comparing the simulated building energy consumptions using four different weather files, one using measured, and three estimated solar radiation from different models, which are Cloud-cover Radiation Model (CRM), Zhang and Huang Model (ZHM), and Meteorological Radiation Model (MRM), and concluded that there was some impact on energy performance of the building due to the using different solar radiation models. However, the result cannot be applied to all other buildings since the simulated office building for that study only used limited building characteristics such as using fixed values of solar heat gain coefficient (SHGC) and window-to-wall ratio (WWR), which are significant parameters related to solar radiation that affect to the building energy consumptions. Therefore, there is a need to identify how the building energy consumption will be changed by varying these building parameters. In this study, the impact of one measured and three estimated global solar radiation on energy performance of the office building was conducted taking account of SHGC and WWR. As a result, it was identified that the impact of four different solar radiation data on energy performance of the office building was evident regardless SHGC and WWR changes, and concluded that the most suitable solar models was changed from the CRM/ZHM to the MRM as SHGC and WWR increases.

• 한국태양에너지학회 논문집
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• 제33권5호
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• pp.9-17
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• 2013

Hourly horizontal global solar radiation has been used as one of significant parameters in a weather file for building energy simulations, which determines the quality of building thermal performance. However, as about twenty two weather stations in Korea have actually measured the horizontal global sola radiation, the weather files collected in other stations requires solar data simulation from the other meteorological parameters. Thus, finding the reliable complicated method that can be used in various weather conditions in Korea is critically important. In this paper, three solar simulation models were selected and evaluated through the reliability test with the simulated hourly horizontal global solar radiation against the actually measured solar data to find the most suitable model for the south east area of Korea. Three selected simulation models were CRM, ZHM, and MRM. The first two models are regression type models using site-fitted coefficients which are derived from the correlation between measured solar data and local meteorological parameters from the previous years, and the last model is a mechanistic type model using the meteorological data to calculate conditions of atmospheric constituents that cause absorption and scattering of the extraterrestrial radiation on the way to the surface on the Earth. The evaluation results show that ZHM is the most reliable model in this area, yet a complicated hybrid simulation methods applying the advantages of each simulation method with the monthly-based weather data is needed.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 제17회 워크샵 및 추계학술대회
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• pp.479-491
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• 2005

지구환경문제와 에너지 수급관계를 감안할 때, 청정 및 대체에너지 연구개발은 불가피하며, 그 중에서도 태양에너지는 대표적인 대안의 하나로 인식된다. 따라서 태양에너지의 적극적인 활용에 필요한 기초자료의 마련은 필수적이다. 태양에너지의 이용 및 관련 절약 기술에 필요한 태양에너지 자원(기상)에 대한 기술자료는 최소한 30년간의 측정 자료를 필요로 한다. 이들 자료에는 시간별 수평면전 일사량, 법선면 직달일사량 및 수평면 산란일사량은 물론 시간별 평균치로 운량, 기온, 습도 등이 포함된다. 이들 자료로부터 자료의 분포, 평균 및 최고, 최저값 등과 같은 기초자료들을 선별하여 관련 시스템 설계에서 요구하는 기준을 충족하여야 하는 것이다. 그러나 우리나라의 경우, 태양에너지 자원에 대한 정밀한 측정은 1982년 이후 수평면 전일사량, 1990년 이후에서나 법선면 직달일사량에 대하여 본격적으로 이루어진 실정으로, 자료의 표준화 및 신뢰성 확보에는 여전히 상당한 시간과 노력이 요구되는 실정이다. 지속적인 측정과 더불어 요구되는 것으로 측정자료의 가공기술을 들 수 있다. 즉, 측정자료의 품질평가 및 관리 기술, 미측정 또는 불량자료의 복원 기술 및 측정 지역외 자료의 추정을 위한 보간기술 등이다. 이와 같은 기초자료 및 기술에 관한 연구개발은 보다 구체적인 적용에 앞서 필수적으로 이루어져야 할 과제이다.

• 설비공학논문집
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• 제29권4호
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• pp.159-166
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• 2017

The growing global interest in energy saving is particularly evident in the building sector. The transmitted solar irradiance is an important input in the prediction of the building-energy load, but it is a value that is difficult to measure. In this paper, a calculation method, for which the total horizontal irradiance that can be easily measured is employed, for the measurement of the transmitted solar irradiance through windows is proposed. The method includes a direct and diffuse split model and a variable-transmittance model. The results of the proposed calculation model are compared with the TRNSYS-simulation results at each stage for the purpose of validation. The final results show that the CVRMSE over the year between the proposed model and the reference is less than 30 %, whereby the ASHRAE guideline was achieved.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 추계학술대회 논문집
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• pp.171-173
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• 2008

The amount of incident solar rays on inclined surfaces with various directions has been widely utilized as important data in installing solar collector, hot water system, and designing solar buildings and house. This is because the performance of the solar energy applied systems is much affected by angle and direction of incident rays. Recognizing those factors mentioned above are of importance, actual experiment has been performed in this research to obtain the angle of inclination with which the maximum incident rays can be absorbed. The results obtained in this research could be used in designing optimal solar thermal systems.