Ecological cleaning of PV panels by exploitation of dew water in Morocco

This work presents an ecological solution for cleaning of photovoltaic (PV) modules and a continuity of our first experience. It consists on using the dew water formed on the surface of the front glass. The study site is in Rabat city in the Northwest of Morocco, at the RDI (Research, Development and Innovation) Solar Energy Platform of ENS. In order to examine the effect of the angle change combined with the formation of dew water, and consequently on the cleaning of PV modules, systematic measurements of soiling ratio were made. The experiments were performed on glass plates that were exposed in real outdoor conditions. The soiling ratio was calculated by measuring the transmitted and received irradiance by the glass. At approximately sunrise, the subsequent permutation of the glass from the horizontal position to a 30 degrees tilt angle promotes the dew droplets flow. The efficiency of cleaning is then investigated. A comparison of the soiling losses of fixed glass and variable glass with dew water flow was presented. It was found that the soiling losses for fixed glass averaged 9.3% during the exposure period while variable glass only marked 3.3%. In other words, the losses due to soiling for the fixed glass generate three times the losses compared to a variable glass with cleaning using dew water. Copyright (C) 2022 Elsevier Ltd. All rights reserved.