LAUSR

ABSTRACT This paper deals with the determination of the optimum tilt angle for south-facing solar surfaces to collect the maximum solar irradiation in Yazd, Iran. In order to increase the accuracy of results, different models are used in this study. The accuracy of the models is compared in terms of the statistical indicators, RMSE and MBE. The results indicate that the Klucher model gives the best results for estimating the solar radiation reaching the solar surfaces. In comparison to the horizontal surface, on average the gain of energy during the year will be 22.82% if a solar surface is installed at yearly optimum tilt angle. For higher efficiency, it is suggested that the solar surface mounts at the seasonal tilt angle. This leads to an increase in the efficiency of the solar surface of more than 8.86% over that of a similar fixed solar surface at the annual tilt angle.