Photovoltaic plant maintainability optimization and degradation detection: Modelling and characterization

Efficiency degradation due to modules soiling is a key factor in photovoltaic plants, which must be accurately taken into account in order to set a maintenance program, which optimizes the production/cost ratio. In this paper a model is developed, which accounts for the losses in the energy production due to dust and other kind of dirt. A small PV system with a proper measurement bench and a reference panel kept clean was set up allowing to identify different shading effects due to different kinds of soiling. Early results allowed identifying different soiling factors on current and voltage. This will enable the development of a smart system optimizing the PV plant maintenance, especially for the module cleaning interventions.