• Journal of the Korean Solar Energy Society
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• v.31 no.2
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• pp.37-46
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• 2011

The GWNU (Gangnung-Wonju national university) solar radiation model was developed with radiative transfer theory by Iqbal and it is applied the NREL (National Research Energy Laboratory). Input data were collected and accomplished from the model prediction data from RDAPS (Regional Data Assimilated Prediction Model), satellite data and ground observations. And GWNU solar model calculates not only horizontal surface but also complicated terrain surface. Also, We collected the statistical data related on photovoltaic power generation of the Korean Peninsula and analyzed about photovoltaic power efficiency of the Gangwon region. Finally, the solar energy resource and photovoltaic generation possibility map established up with 4 km, 1 km and 180 m resolution on Gangwon region based on actual equipment from Shinan solar plant,statistical data for photovoltaic and complicated topographical effect.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.413-416
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• 2009

Since the solar radiation is main input for sizing any solar photovoltaic system and solar thermal power system, it will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 and direct normal insolation data since December 1992 at 16 different locations. Because of a poor reliability of existing data, KIER's new data will be extensively used by solar energy system users as well as by research institutes. Among some significant results, the yearly averaged horizontal global insolation was turned out 3.61 kWh/$m^2$/day and the yearly mean 5.38 kWh/$m^2$/day of the direct normal insolation was evaluated for clear days.

• Journal of Advanced Marine Engineering and Technology
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• v.37 no.7
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• pp.799-806
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• 2013

As a first step to develop the hybrid power generation system, on this study, the time-variable resources of wind and solar radiation of Yeongdo, Busan, Korea had been measured during June and July 2013. And the quantity of generated wind power and solar photovoltaic had also been measured during the same period. It is found out that the wind mainly flew from southwest at the average speed of 2 m/s during 2 months. And it is clear that, because of the low wind velocity, the wind quality to generate the power seems not enough at this area. Meanwhile solar radiation was measured every daytime (6:00~19:00) and the peak solar radiation occurred around 12:00~14:00. And it is clear that the time-based variations of quantity of generated power were proportional to the variations of these resources, respectively. As a proposal, these 2 natural energies can be combined as resources of a hybrid system, because these 2 patterns are not overlapped so much on time base.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.3
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• pp.486-495
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• 2009

This paper proposes a new methodology on reliability evaluation of a power system including solar cell generators (SCG). The SCGs using renewable energy resource such as solar radiation(SR) should be modeled as multi-state operational model because the uncertainty of the resource supply may occur an effect as same as the forced outage of generator in viewpoint of adequacy reliability of system. While a two-state model is well suited for modeling conventional generators, a multi-state model is needed to model the SCGs due to the random variation of solar radiation. This makes the method of calculating reliability evaluation indices of the SCG different from the conventional generator. After identifying the typical pattern of the SR probability distribution function(pdf) from SR actual data, this paper describes modelling, methodology and details process for reliability evaluation of the solar cell generators integrated with power system. Two test results indicate the viability of the proposed method.

• Journal of the Korean Solar Energy Society
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• v.32 no.3
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• pp.68-76
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• 2012

Since the solar energy resource is the main input for sizing any solar energy utilization system, it is essential to utilize the solar radiation data as an application and development of solar energy system increase. It will be necessary to understand and evaluate the insolation data. The Korea Institute of Energy Research(KIER) has begun collecting horizontal global insolation data since May, 1982 at 16 different locations in Korea and for the more detailed analysis, images taken by geostationary satellite may be used to estimate solar irradiance fluxes at earth's surface. It is based on the empirical correlation between a satellite derived cloud index and the irradiance at the ground. From the results, the measured data has been collected at 16 different stations and estimated using satellite at 44 different stations over the Korean peninsula from 1982 to 2010. The Result of analysis shows that the annual-average daily global radiation on the horizontal surface is 3.66 $kWh/m^2/day$ and estimated solar radiation fluxes show reliable results for estimating the global radiation with average deviation of -7.2 to +3.7 % from the measured values.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.67.2-67.2
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• 2011

It is necessary to estimate empirical constants in order to predict the monthly mean daily global radiation on a horizontal surface in the developing areas for alternative energy. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for any areas over Korea by calculating the regression models taking into account latitude, percentage of possible sunshine, and cloud cover. From the results, the single linear equation proposed by using percentage of possible sunshine method shows reliable results for estimating the global radiation with average annual deviation of -3.1 to +0.6 % from measured values.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.235-238
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• 2009

It is necessary to estimate empirical constants in order to predict the monthly mean daily global radiation on a horizontal surface in the developing areas for alternative energy. Therefore many different equations have proposed to evaluate them for certain areas. In this work a new correlation has been made to predict the solar radiation for any areas over Korea by calculating the regression models taking into account latitude, percentage of possible sunshine, and cloud cover. From the results, the single linear equation proposed by using percentage of possible sunshine method shows reliable results for estimating the global radiation with average annual deviation of -3.1 to +0.6 % from measured values

• New & Renewable Energy
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• v.9 no.2
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• pp.15-22
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• 2013

The solar energy are an infinite source of energy and a clean energy without secondary pollution. The global solar energy reaching the earth's surface can be calculated easily according to the change of latitude, altitude, and sloped surface depending on the amount of the actual state of the atmosphere and clouds. The high-resolution solar-meteorological resource map with 1km resolution was developed in 2011 based on GWNU (Gangneung-Wonju National University) solar radiation model with complex terrain. The very high resolution solar energy map can be calculated and analyzed in Seoul and Eunpyung with topological effect using by 1km solar-meteorological resources map, respectively. Seoul DEM (Digital Elevation Model) have 10m resolution from NGII (National Geographic Information Institute) and Eunpyeong new town DSM (Digital Surface Model) have 1m spatial resolution from lidar observations. The solar energy have small differences according to the local mountainous terrain and residential area. The maximum bias have up to 20% and 16% in Seoul and Eunpyung new town, respectively. Small differences are that limited area with resolutions. As a result, the solar energy can calculate precisely using solar radiation model with topological effect by digital elevation data and its results can be used as the basis data for the photovoltaic and solar thermal generation.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.409-412
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• 2009

In this research, the intensity of solar energy, which was injected to the different angle plane every hour day by day, was technically documented and quantitatively analyzed through actual observations. In order to group every days into days with similar intensity, graph was drawn with respect to time for every day and each area value under the curve was calculated. Then, the search for grouped days having similar intensity curve patterns was carried out and the optimum incident angle of absorber plate was derived to maximize the efficiency of solar energy systems.

• Journal of Navigation and Port Research
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• v.37 no.1
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• pp.79-84
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• 2013

For the diversity of energy supply system and the improvement in the habitants' living environments of the islands, it is possible and necessary to use the natural energy as resources of the electric power generation system. In this study, the characteristics of wind and solar radiation on 4 islands offshore Namhae-Tongyoung of Korea were measured for one year from November 2010 to October 2011 and analyzed in relation to energy resources survey. As a result of measurement and analysis, the respective wind rose diagrams of 4 islands were made, and showed that the frequencies of wind directions were quite different from among the islands. The Rayleigh probability distribution of wind velocity showed that the wind speeds of KR and SS were mainly 2~5m/s, and the respective quantities of electric power generation of 4 islands were shown to be different. The variation of solar radiations and potential quantity of those uses were measured to be similar to each other among 4 islands.