Diffuse fraction for Antananarivo Madagascar

The aim of this paper is to find the best model to estimate the hourly solar diffuse fraction by the clearness index for the town of Antananarivo, Madagascar. Per minute data of solar diffuse and global irradiance in horizontal plane during four years were used to build the three-piece defined model. Then, eight models in the literature were applied to compare for the present model by 09 statistical criteria. The result shows that the present model is the best and is the only one that can fulfill all statistical criteria.