Quality control of diffuse solar radiation component with satellite-based estimation methods

Abstract

In order to analyze solar systems, it is very important to determine the accurate solar radiation components belonging to any region. These components are defined as the beam and diffuse. The diffuse radiation component may not always be determined accurately since it is mostly affected by many geographical factors and climatic features in addition to the location parameters. Therefore, this work aims to compare and evaluate the validity of global and diffuse estimation methods for nine locations in Turkey. The satellite-based estimation methods (HELIOSAT, Meteonom, and PVGIS) mentioned in the literature were used to estimate global and diffuse radiation. These selected methods were statistically tested with accurate ground measured data. For HELIOSAT, the global radiation is varying −0.02 and 0.03, and 0.010 and 0.035, respectively, Relative MBE and Relative RMSE. Similarly, the diffuse radiation values are −0.020 and 0.025 for Relative MBE, and 0.015 and 0.030 for Relative RMSE. The goodness of the fit values for the HELIOSAT method shows a very good agreement with at least 97% confidence level of global and 91% of diffuse radiation values. Thus, HELIOSAT method shows a trustworthy alternative to the ground measurement data when reliable global and diffuse radiation data are not available.