Analysis of soiling loss in photovoltaic modules. A Review of the Impact of atmospheric parameters, soil properties, and mitigation approaches

Soil accumulated on a photovoltaic (PV) module can significantly reduce the transmittance of the cover glass, resulting in power losses and consequent economic losses. Natural atmospheric parameters influence the accumulation of soil at various geographic locations. In this paper, the approaches and outcomes of the research studies on either indoor (simulator-based) or outdoor (field-based) PV soiling have been thoroughly reviewed. It has been noted that conducting an indoor study is necessary in order to estimate future power losses prior to the installation of a solar PV power plant. Different parameters depicted for the power loss due to the soiling of PV modules are analyzed individually and presented. Moreover, this study delves into a detailed examination of the key factors influencing dust depositions on PV modules in various geographical regions, with a particular focus on their relationship with climatic conditions. This study demonstrates that the soiling effect on PV modules is site-specific, necessitating the investigation of optimal cleaning procedures to suit a certain climate while considering cost effectiveness. This way, probable future research directions to quantify soiling losses are identified. In addition, different loss prevention and mitigation techniques are also reviewed. This makes it possible to highlight effective strategies and pinpoint potential future research lines in these areas.