SENTINELLA: A WSN for a smart monitoring of PV systems at module level

Monitoring a PV plant has a remarkable impact on its efficiency. In this context, Wireless Sensor Networks (WSNs) can be a low cost, but reliable solution to perform the real-time monitoring task. The main objective of this work is the realization of a WSN that allows to monitor at panel level the efficiency of Photovoltaic (PV) panels, to provide data useful to investigate on causes of efficiency losses and to detect inertial events possibly related to attempts of theft or tampering but also to mechanical striking events. Nodes of the WSN, which are installed on each PV module, are equipped with voltage, current, irradiance, temperature and inertial sensors. Acquired data are then transferred to a management center which is in charge of estimating efficiency losses and correlated causes, tampering and inertial events at the level of the single module. In particular, this paper is focused on a solution for the automatic estimation of efficiency losses of a PV module and related causes.