EASY-PV: A ready-to-market EGNSS high Accuracy System improving photovoltaic plant maintenance

Global Navigation Satellite System (GNSS) Real Time Kinematic (RTK) is the key enabling technology for a number of applications that require very high positioning accuracy as their operational requirement. This include, but not limited to, mapping, surveying, robot guidance, and precision agriculture to name a few. Typically, GNSS RTK employs high end dual-frequency receivers and antennas to deliver precise positioning that, in some way, restricts the use of GNSS RTK to a subset of user market due to very high cost. The emerging mass market user applications, however, require centimetre positioning accuracy considering a cost-effective solution. This, on one hand, calls for low-cost GNSS RTK technology, and on the other hand, opens up new possibilities for mass-market user applications to make use of GNSS high accuracy positioning in a number of ways. One of the applications that make use of low-cost RTK is the EASY-PV, EGNSS high Accuracy SYstem for improving photovoltaic (PV) plants maintenance. As photovoltaic plants are aging, it is not uncommon that their production lowers due to inefficiency caused by unknown modules on the plant lowering the whole plant’s productivity. Thermal inspections are valuable for PV owners and maintainers, but relevant procedures (currently performed by operators with handheld cameras) are time demanding and sometimes expensive due to safety costs for the personnel involved in the operations (e.g.: PV modules on roofs, rough areas, …). It stands to reason that today such operations are not fully automated yet and the responsive recognition of a broken module might result very difficult in a large PV plant. As a first improved solution, the growing technology of RPAS (Remotely Piloted Aircraft Systems) is exploited to gather thermal images which are geo-referenced by GPS positioning and processed by computer vision algorithms. However, this configuration is very respectful but still not enough in order to provide the required positioning accuracy for the automation and fast identification of the broken modules. Only the aid of accurate positioning allows a cost effective solution to reduce time, costs and risks for personnel involved. Finally, EASY PV solution is conceived to build up an automatic system for acquiring, geo-referencing and processing both visible and thermal images captured by an RPAS equipped with a Galileo high accuracy receiver, flying over a photovoltaic field. In this way it is possible to easily (i.e. automatically, with safety improvement for operators and saving time) detect the defective modules to be replaced.