Tilt angle optimization for maximum solar energy collection - Case study for Ifrane, Morocco

Abstract

The design of any solar-based conversion system requires the determination of the optimal tilt surface angle at which maximum solar energy can be collected. This paper examines the theoretical aspects that determine the optimal tilt angle and makes recommendations on how to increase the solar energy collected by varying the tilt angle. Our calculations are based upon the values of daily global radiation on a horizontal surface in Ifrane, Morocco. We assume the solar collectors' surface to be facing the equator. A mathematical model is developed to calculate solar radiation on an inclined surface as a function of the tilt angle. Our study shows that the monthly optimal tilt angle allows maximum solar radiation collection. We also show that optimal solar radiation collection is approximately achieved if the tilt angle of solar collectors is seasonally adjusted. The loss in the amount of solar radiation collected is found to be 1.25 % if the seasonal optimal tilt angle is adopted instead of the monthly optimal one. Annual optimal tilt angle is found to be approximately equal to the latitude of the location.7.26 % energy loss is calculated when using the yearly fixed angle instead of the monthly optimal tilt angle.