A modal study on the estimation of daily global solar radiation from sunshine duration

Building solar plants with suitable placement in the correct geographic areas by utilizing information of solar radiation is the starting point of an investment projects of a solar energy facility. In these premises, several solar radiation models have been improved in order to estimate the solar radiation at a given location, all around the world. Complete and accurate solar radiation data at a specific region are quite important for the solar energy related researches. A number of formulas and models have been developed to estimate solar radiation for the locations, where measured values are not available. Thus, several empirical correlations have been developed in the literature. In this study, models such as the Angström equation, which is reviewed in literature, are used to estimate global solar radiation from sunshine duration in Turkey. In addition, the solar radiation models were examined at the identified solar radiation regions. This study investigates either the correctness of the model itself or the correctness of the estimation of global solar radiation, based on a set of statistical parameters such as R2, RMSE, MBE, MABE, MPE and MAPE.