Output power loss of crystalline silicon photovoltaic modules due to dust accumulation in Saharan environment

Photovoltaic (PV) module efficiency is much lower when operating in outdoors than under controlled laboratory conditions. Dust accumulation on the surface of PV modules results in lower performance and daily energy losses due to the decrease in glass cover transmittance. These losses in energy output are significant in large PV farms especially in arid and desert areas. In this research, the effect of dust accumulation on the performance of crystalline PV modules was investigated experimentally under outdoor conditions in a Saharan environment at the city of Ouargla, Southeast of Algeria. In addition, the power generation of a 30 MW grid-connected PV power plant installed in the same area before, during and after a sandstorm was evaluated. The results showed that approximately 4.36 g/m(2) of dust accumulated on the PV module's surface after 8 weeks of outdoor exposure without cleaning. This caused a drop in PV energy production of 8.41%, 6.10% and 0.51% in maximum power output, short circuit current and open circuit voltage respectively in comparison to a cleaned PV module. Furthermore, deposited dust on the surface of the PV modules at this farm from this sandstorm led to a 32% reduction in generated energy (i.e. 5.18 MWh).