The Influence of Cleaning Frequency of Photovoltaic Modules on Power Losses in the Desert Climate

Abstract

Dust accumulation on the photovoltaic (PV) surface decreases the solar radiation penetration to the PV cells and, eventually, the power production from the PV system. To prevent dust-based power losses, PV systems require frequent cleaning, the frequency of which depends on the geographical location, PV integration scheme, and scale of the PV power plant. This study aims to measure the drop-in radiation intensity, as well as power output, due to dust and to determine the optimal time interval for PV cleaning in the United Arab Emirates (UAE) climate. In this research, a dusting study experiment was carried out at the Renewable Energy Laboratory, Falaj Hazza Campus, UAE University, Al Ain, UAE, for 3.5 months, from 22 April 2018 to 7 August 2018. To measure the pure radiation losses caused by the dust, four transparent glasses were used to mimic the top glass cover of the PV modules. The dusting induced power losses were measured for four selected PV cleaning frequencies (10 days, 20 days, 1 month, and 3 months). This study revealed that up to 13% of power losses occurred in PV panels that remained dusty for 3 months, compared to panels that were cleaned daily. PV cleaning after 15 days brought the losses down to 4%, which was found the most feasible time for PV cleaning in this study, considering a reasonable balance between the cleaning cost and energy wasted due to soiling.

A review of dust accumulation on PV panels in the MENA and the Far East regions

“…Proper estimation of when to start cleaning of solar panels is a compromise between gross costs of cleaning the panels and how much reduction in efficiency of solar panels can be tolerated. Shah et al [154] studied the optimal time interval for PV cleaning in the UAE climate. This study revealed that the output power of the panels that remain uncleaned for 3 months decreased by 13% compared with the panels that were cleaned daily.…”

“…4) It takes less time to decay compared with hydrophilic coatings. 5) Depends on rainfall 6) High initial costs in case of large-scale PV systems perform the cleaning cycle for the installed PV systems in the MENA region on a weekly or biweekly basis [26,37,57,61,[154][155][156][157]. On the other hand, the majority of the PV systems in Europe are installed in rainy green regions, and the optimum pattern for cleaning is less frequent than that in the MENA and the Far East regions.…”

The Effects of Soiling and Frequency of Optimal Cleaning of PV Panels in Palestine

“…The drop in electric power compared to a daily cleaned reference PV module was 3%, 5% 7%, and 13% for 10 days, 20 days, 1 month, and 3 months respectively [58]. AL-Housani et al…”

Cleaning frequency of the solar PV power plant for maximum energy harvesting and financial profit

“…The accumulation of dust on the surfaces of PV panels significantly degrades the access of solar radiation to them, and to prevent the loss of energy resulting from the dust accumulated on the surfaces of modules requires frequent cleaning of PV systems, its availability depends on the geographical location of solar plants [1]. There is a range of existing water pumping systems in Sharjah that rely on traditional and renewable energy sources like solar photovoltaic panels, mechanical types of windmills, diesel generators and wind turbines.…”