Influence of cleaning using water and surfactants on the performance of photovoltaic panels

Dust accumulation on photovoltaic (PV) panels, especially in desert areas, can obscure the solar radiation, and therefore reduce the efficiency of the panels dramatically. The objective of this research is to remove dust deposited on PV panels using the minimum amount of water and energy. In this research the influence of cleaning on the PV panels using water as well as a surfactant was investigated experimentally using a non-pressurized water system. The PV panels under consideration are part of a 14-kW PV power plant installed in the German University in Cairo (GUC), Egypt. It was found that the efficiency of the PV panels has decreased by 50% after 45 days of cleaning using non-pressurized water, while the efficiency remained constant when a mixture of anionic and cationic surfactants was used for cleaning. Cleaning the PV panels using the developed water system and a mixture of surfactants minimizes the amount of water needed for cleaning as well as the energy for spraying the water.

► It is not possible to clean PV panels in sandy regions using non-pressurized water.
► PV panels can be cleaned by a mixture of anionic and cationic surfactants.
► Cleaning of PV panels using a mixture of surfactants saves energy and water.