The effect of rain on photovoltaic systems

Photovoltaic technology can be considered a key energy source for the future sustainable development, therefore it's important to carry out a continuous and comprehensive investigation about its actual energy performance in various climatic conditions. More in detail, crystalline silicon technology is currently dominating the market, thus an in-depth assessment on its specific behaviour is essential. In this sense, numerous studies have been performed in the past decades to assess the influence on the energy production of crystalline photovoltaic modules of several factors, such as spectral quality of solar irradiance, temperature, wind speed, soiling, snow etc. but so far the effect of rain appears scarcely investigated. In such a framework, the present work represents a detailed assessment of the rain effect on the performances of crystalline silicon technology, carried out both under a theoretical and experimental viewpoint, with a focus on the temperate climates of European context. Obtained results are promising and confirm that the overall impact of rain can have non-negligible positive influences on the energy productivity of photovoltaic systems, mainly for thermal and optical reasons, paving the way for further studies on the topic