Evaluation of models to predict solar radiation on tilted surfaces for the Mediterranean region

Abstract

The validity of various models for predicting the solar radiation on inclined surfaces was investigated by employing 2-year measured hourly irradiation data on horizontal and vertical surfaces for Nicosia, Cyprus. Models using isotropic and anisotropic distribution of sky radiance are evaluated. The results indicate that the annual root mean square error for all the tested algorithms varies from 3.6 to 7%.