Advanced Method for Determining Soiling Losses on PV Modules in Desert Climate

33rd European Photovoltaic Solar Energy Conference and Exhibition; 1813-1818 Dust deposition on the surface of PV modules (soiling) leads to significant losses in energy yield particularly in desert climates, where high daily yield losses due to soiling can be observed. However, its estimation is still an open challenge in PV modeling. The intensity of soiling losses strongly depends on its environmental conditions. The aim of this paper is the development of a method to determine the soiling losses and to classify the soiling state of PV modules in desert climate. Therefore, the paper combines the results from indoor and outdoor measurements on PV modules with two types of front glasses. The outdoor parameters were measured in the research platforms of photovoltaic modules at “Green Energy Park” by IRESEN in Morocco for several months. During our investigation, different cleaning scenarios were implemented for different modules in both groups. The application of a multi-dimensional classification and clustering as well as parameter correlation enabled the determination of the impact of environmental data on module soiling on a daily basis. Thus, for each cluster its corresponding averaged soiling loss can be calculated. In terms of module current, the impact of the soiling is between the three classes 11 to 44 mA at high irradiation conditions.