Development of Site Specific Optimal Tilt Angle Model for Fixed Tilted Plane PV Installation ın Akwa Ibom State, Nigeria

Abstract

Photovoltaic (PV) panels’ orientation (azimuth angle) and tilt angle significantly affect the energy output of PV power plants. The reason is because the photovoltaic panels produce more electric energy when their surfaces are perpendicular to the sun's rays. Researchers have developed models for estimating the optimal tilt angle for any given location across the globe. In this paper, a site specific model is developed for more accurate estimation of the optimal tilt angle for fixed-tilt angle PV installations at the Ibom E-Library in Uyo metropolis, Akwa state of Nigeria. The solar radiation data used for the study was obtained from the National Aeronautics and Space Administration Surface meteorology and Solar Energy (NASA SSE) website. PVsyst simulation software was used to perform the transposition of the global radiation on horizontal plane to tilted plane. For the location with latitude of 5.123° the existing model estimated the optimal tilt angle as 7.16035° whereas, the site-specific model estimated 11.5° for the optimal tilt angle. The model has prediction accuracy of 99.77% and root mean square error of 0.002567. The optimal tilt angle model can be employed for fixed tilted plane PV installations in the nearby locations.