The Experts below are selected from a list of 8688 Experts worldwide ranked by ideXlab platform
Amirhosein Ghaffarianhoseini - One of the best experts on this subject based on the ideXlab platform.
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empirical correlations as a means for estimating monthly average Daily Global Radiation a critical overview
Renewable Energy, 2014Co-Authors: Edward Halawa, Amirhosein GhaffarianhoseiniAbstract:In regions where solar energy is abundant, solar energy can play a vital role in attaining energy sustainability. Sizing solar energy systems requires the availability of solar Radiation data on horizontal surface which can then be used to calculate solar Radiation intensity on any tilted surface using appropriate conversion factors or formula. In many parts of the world, especially in developing countries, such data is not readily available. Many researchers have found that monthly average Daily value of Global solar Radiation on horizontal surface can be estimated when meteorological parameters such as duration of sunshine, number of rainy days, relative humidity, etc. are available. Many empirical correlations have been developed based on this approach. The development of such a correlation has been made possible through the availability of solar and other meteorological data required for their validation. This paper presents a review on the existing empirical correlations and critically looks at the practicality of such correlations. This raises the question on the appropriateness of the past and present approaches adopted by researchers in this field. The paper also discusses various related aspects and proposes new directions for future research.
Yan Gang - One of the best experts on this subject based on the ideXlab platform.
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general formula for estimation of monthly average Daily Global solar Radiation in china
Energy Conversion and Management, 2005Co-Authors: Zhou Jin, Wu Yezheng, Yan GangAbstract:Solar Radiation and sunshine duration data from 69 meteorological stations in China was used to develop the formula for estimating the monthly average Daily Global Radiation on a horizontal surface. Several models and correlations that embrace such variables as the fraction of sunshine duration, the latitude and the altitude have been selected, tested and compared to decide which model is recommended on the basis of statistical error tests. In this study, using the relative duration of sunshine as a single independent variable, the most accurate equation that is expressed in a third order form was obtained for each station. The results show that the coefficients are site dependent. Subsequently, taking the Radiation data and geographical parameters at all 69 stations as reference, a countrywide general equation was established. Compared with the equation using the relative duration of sunshine as a single independent variable, the general equation shows relatively lower accuracy, but estimating the Global solar Radiation by this equation has proved sufficiently reliable. This equation can be used to estimate the monthly average Daily Global Radiation in areas where the Radiation data is missing or not available, so that a geographical distribution of Global solar Radiation across the country may be obtained.
Can Ertekin - One of the best experts on this subject based on the ideXlab platform.
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evaluation of Global solar Radiation models for konya turkey
Energy Conversion and Management, 2006Co-Authors: Hakan Okyay Menges, Can Ertekin, Mehmet Hakan SonmeteAbstract:Abstract Solar Radiation data are required by solar engineers, architects, agriculturists and hydrologists for many applications such as solar heating, cooking, drying and interior illumination of buildings. In order to achieve this, several empirical models have been developed to predicted the solar Radiation all over the world. The main objective of this study is to review the Global solar Radiation models available in the literature. In order to evaluate the applicability of 50 models for computing the monthly average Daily Global Radiation on a horizontal surface, the geographical and meteorological data of Konya, Turkey (37°52′N latitude, 32°29′E longitude) was used. The models were compared on the basis of statistical error tests such as the percentage error (e), mean percentage error (MPE), root mean square error (RMSE), mean bias error (MBE), regression coefficient (R) and Nash–Sutcliffe equation (NSE). According to the results, the Ertekin and Yaldiz model showed the best estimation of the Global solar Radiation on a horizontal surface for Konya, Turkey, by means of the MPE (0.004266%), RMSE (0.022576 MJ/m2), MBE (0.000000 MJ/m2), R (0.999993) and NSE (0.999985) statistical tests: H = 20.296019 - 0.096134 H 0 + 0.317593 δ - 0.146422 RH + 10.705159 S S 0 - 0.288332 T + 0.021331 TS + 0.359791 C + 0.207588 P - 0.076444 E
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Estimation of monthly average Daily Global Radiation on horizontal surface for Antalya (Turkey)
Renewable Energy, 1999Co-Authors: Can Ertekin, Osman YaldizAbstract:In this study, multiple linear regression models were used to estimate the monthly average Daily Global Radiation using nine different variables for Antalya, Turkey; the extraterrestrial Radiation, solar declination, mean relative humidity, ratio of sunshine duration, mean temperature, mean soil temperature, mean cloudiness, mean precipitation and mean evaporation. The results showed that the models can estimate Global Radiation within relative error (|e|) of −5.7 and 3.9%, a mean error (MPE) of 2.0% and root-mean square error (RMSE) of 2.5% for Antalya.
Mohd Yusof Othman - One of the best experts on this subject based on the ideXlab platform.
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estimates of monthly average Daily Global solar Radiation in malaysia
Renewable Energy, 1992Co-Authors: Kamaruzzaman Sopian, Mohd Yusof OthmanAbstract:Abstract Estimates of the monthly average Daily Global Radiation for eight locations in Malaysia has been made using hours of bright sunshine. The data from Bandar Baru Bangi was obtained from the Solar Energy Research Laboratory at the Department of Physics, Universiti Kebangsaan Malaysia while others were obtained from the Meteorological Department. The least square linear regression analysis was used for the eight cities to obtain the relationship between the monthly average Daily Global Radiation and sunshine duration data. The Angstrom's correlation obtained for the eight cities can be used for any solar energy application in Malaysia.
Osman Yaldiz - One of the best experts on this subject based on the ideXlab platform.
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Estimation of monthly average Daily Global Radiation on horizontal surface for Antalya (Turkey)
Renewable Energy, 1999Co-Authors: Can Ertekin, Osman YaldizAbstract:In this study, multiple linear regression models were used to estimate the monthly average Daily Global Radiation using nine different variables for Antalya, Turkey; the extraterrestrial Radiation, solar declination, mean relative humidity, ratio of sunshine duration, mean temperature, mean soil temperature, mean cloudiness, mean precipitation and mean evaporation. The results showed that the models can estimate Global Radiation within relative error (|e|) of −5.7 and 3.9%, a mean error (MPE) of 2.0% and root-mean square error (RMSE) of 2.5% for Antalya.
