Long-term Energy Generation Efficiency of Solar PV System for Self-consumption

We have developed an isolated-type hybrid solar PV system (HyPV) operating under stand-alone PV mode or grid mode, interchangeably by an ATS (automatic transform switch) [1]. No solar PV power is fed to grid. The energy generation efficiency of HyPV is actually the same as the stand-alone solar PV which is usually lower than that of FIT (feed-in-tariff) PV systems (feeding all solar power to grid for tariff through a MPPT/inverter) due to the unbalance between battery storage capacity and variations of solar radiation and load demand. In the present study, we has shown from long-term field test of five HyPV systems, that the energy generation efficiency of HyPV is very close to that of FIT PV systems.