Soiling Forecasting in Large Grid-Connected PV Plants and experience in Spain

Soiling of PV modules is an issue causing non-negligible losses on PV systems. Cleaning activity is the most common way to mitigate soiling. The impact of this cleaning activity can be significant, both in terms of cost and resources consumption. For these reasons, it is important to monitor and predict soiling profiles and establish the optimal cleaning time. Especially in locations where the raining is irregular, it is also important to know how precipitation affects soiling ratio. This paper presents the results of soiling analysis and forecasting experience in large grid-connected PV plants in Spain (above 200 MW), proposing a model that helps the decision-making process of the cleaning scheduling.