Effect of Dust Accumulation on the Performance of PV Modules under Cairo Climate Conditions

Abstract

In Egypt, there is a great concern about using photovoltaic systems in solving the electricity shortage problems, especially Egypt lies in the sunbelt regions and receive an average daily solar radiation of about 7 kWh/m 2 . Among the environmental factors that affect the performance of the PV systems such as insolation level, ambient temperature and wind speed, the dust accumulation is considered big challenge. Dust accumulation degrades the PV module output due to absorbing or scattering solar radiation. Cleaning the module surfaces regularly can recover the effect of dust. For good design and operation of the photovoltaic systems, the effect of dust should be studied. This work aims to investigate the effect of dust deposition on the glass cover of photovoltaic modules. The paper introduces an experimental comparison between five modules installed on the same mechanical structure and running simultaneously at the same operating condition with different cleaning scenarios, for three months in the summer season. The results indicated that the instantaneous power output from the modules is degraded proportionally to the amount of attached dust. Referred to the output power of a clean photovoltaic module, the dirty modules lost about 2.39%, 10.89%, 30.16% and 41.97%, if they are cleaned one time per week, per month, per two months and every three months, respectively.