Using drone-supported thermal imaging for calculating the efficiency of a PV plant

The profitability of a PV plant is strictly related to its maintenance. Failures can occur during the lifetime of the modules, the strings and all the other devices that operate in a PV plant. For this reason, it is extremely important to carry out a policy of maintenance that optimizes the operational costs and maximizes the energy production of the plant. One of the most promising maintenance policies is based on imaging techniques like visual inspections, thermography and electro-luminescence performed using unmanned aerial vehicles (especially for large PV plants). These techniques produce a large amount of raw data that are to be analyzed to calculate the return of maintenance interventions or substitutions. These decisions can be taken only comparing the economic losses due to a failure with the repairing cost. This paper, starting from well-known mathematical models of PV modules, proposes an innovative approach to correlate the results of a thermographic inspection with the power losses and the consequent income reduction. This approach is a valid tool for supporting decisions about the maintenance actions on PV plants.