Abstract

A general mathematical formula for shadow in horizontal solar fields is derived. Where the shadow occurs on the rows of the solar field due to the falling shadow of one row onto the next row. Shadow dimensions depend on the spacing between the rows, row length and width, azimuth and tilt angles of the solar collectors, field latitude angle and the time. Hourly year-round behaviour of the shadow are discussed related to the design parameters of the solar field. From the obtained results the following conclusions may be drawn: The shadowing area increases as moving north in the northern hemisphere. For time (day and hour), shadow is closely related to the solar altitude angle, the higher angle the smaller shadow. The distance separating the rows plays crucial role in shadow analysis, increasing distance separating the rows leads to fast decreases the shading. However, optimization of the distance separating the rows is a multi-objective optimization problem involves energetic-economic analysis. In general, increasing the tilt angle leads to an increase in shading. However, the optimum tilt angle is restricted by captured maximum solar radiation on the collector’s surface.

Keywords: PV solar field; Shadow; Design parameters