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Rules and Issues of Outdoor Infrared Inspection of Photovoltaic Modules by Unmanned Aerial Vehicles

The large diffusion of PhotoVoltaic (PV) plants is helping to reduce the CO2 emissions, but it is important that the energy performance of PV systems remain high throughout their operational life. Thus, an effective and detailed monitoring is necessary for large PV plants, because failures can cause high power loss, due to the large amount of PV modules. Infrared (IR) analysis is effective and reliable to detect anomalies or failures in PV modules, but it is time consuming and then expensive, when the IR inspection of large PV plants is manual. A valid support is represented by Unmanned Aerial Vehicle (UAV) equipped by IR camera. Nevertheless, the use of UAV is regulated by international and national rules; consequently, it is not always possible to use an UAV, or its utilization is limited, based on geographic area. Moreover, IR analysis requires additional considerations when done by UAV, due the increased distance and the variable view angle, depending on the UAV movement while patrolling the PV plant. This paper deals with these issues and suggest alerts that the user should consider before planning an UAV-based IR inspection of a large PV plant.