The PV plant shows design failures such as self-shading, near shading, and the inadequate tilt angle. Vegetation has grown around and under the modules, which has caused hot cells on the system. No earthing between modules was found, the structure had no insulation coating, an inverter works under “UNGV” alarm, and leak current was present. It is recommended to: (i) increase the cleaning frequency, (ii) install an irradiation sensor on the tilted plane to estimate and check the Performance Ratio, (iii) ensure the operator’s security, and (iv) a new method to fix the modules shall be used. The estimated production boost expected by the retrofitting actions lies between 5% and 15%.
No earthing connection between modules.
No insulation coating on structure could represent a risk for maintenance workers and engineers while performing O&M works in case of current leakage.
Existence of current on system after the inverter was turned off.