MATLAB/simulink based simulation of solar incidence angle and the sun's position in the sky with respect to observation points on the Earth

Abstract

This paper proposes a simulation model for calculation of the sun's position in the sky and the incidence angle of sunlight beams on the surface of solar modules with any tilt angle, located at any geographical location on the Earth's surface. The electrical power generated by a solar panel directly depends on the amount of the received solar irradiance on panel surface where the received irradiance is directly proportional to the sun's position in the sky. Therefore, it is of great importance for solar energy researchers and system designers to have a precise knowledge about the movement and position of the sun in the sky with respect to any specific observation point on the earth. A simple and practical simulation model of the sun's position in the sky is designed using MATLAB/Simulink platform. The model simulates the sun's position in the sky and solar angle of incidence based on the latitude and longitude of the observation point, solar module's azimuth and tilt angle values, the Julian day number and the local clock time. The proposed model provides the possibility of instantaneous or continuous determination and tracking of the sun's position in the sky for any geographical location on earth and can be considered as a helpful tool for sun tracking and other system planning purposes.