A framework of optimum cleaning schedule and its financial impact in a large-scale PV solar plant: a case study in Senegal

The performance of large-scale PV solar plant installed in sub-Saharan regions is affected by the deposition of dust on the surface of the PV modules. Frequent cleaning of the PV modules increases the profitability of PV solar plants. The objective of this study is to determine the optimal cleaning cycle of a PV solar plant subjected to a wind loaded with sand and dust. This study took place in a PV solar plant installed in Senegal. The measurement data are analysed for a period of two years and used to extract soiling rate. Optimization was done based on the total cost caused by dust on the PV solar plant to minimize the number of days between cleaning events. The results showed that the soiling rate between June and May is 0.34%/day, while a rate of 0.33%/day was recorded in October. The highest soiling rates of 0.42%/day and 0.49%/day were recorded in December and between February and March, respectively. The optimal cleaning cycle for the PV solar plant is 14 days. The total cost of cleaning is reduced by 31% using this optimal cleaning cycle proposed.