Using Sunshine Duration and Satellite Images to Estimate Daily Solar Irradiation on Horizontal Surface
Abstract
The use of satellite measurements for the estimation of solar irradiation at the Earth surface is rapidly increased in the 21st century. The accuracy of such estimations yet should be modified to attain more reliable input values for the use of all types of solar energy systems. This paper presents a new alternative approach aiming to increase the estimation accuracy of daily solar irradiation by coupling the satellite images with surface bright sunshine hour measurements. This approach is described for the estimation of global solar irradiation on daily base by using bright sunshine hour data for two regions, one in Turkey and one in Germany, respectively. Using one-year data, daily solar irradiation values for these two different stations have been calculated and standard error analyses are carried out to analyze the performance of the correlations. The results are compared with the estimation of a commonly used satellite model (HELIOSAT) and the Angstrom model using measurements of daily global solar irradiation.