On the Use of Dew for Cleaning PV Panels in Morocco: Literature Survey and Experimental Results

This paper proposes an ecological solution for cleaning of photovoltaic (PV) modules. It consists on using the dew water formed on the surface of the front glass. Two different sites were studied in order to examine the effect of tilt angle on the formation of dew water, and consequently on the cleaning of PV modules. Systematic measurements were made in Rabat city as well as in Taroudant located in the southwest of Morocco. The experiments were performed on glass plates that were exposed in real outdoor conditions. At approximately sunrise, the subsequent permutation of the glass from the horizontal position to a 30° tilt angle promotes the dew droplets flow. In both sites, the soiling ratio was calculated by measuring the transmitted and received irradiance by the glass. The efficiency of cleaning is then investigated.