Abstract
Battery energy storage systems (BESSs) are increasingly adopted to mitigate the negative effects caused by the intermittent generation of photovoltaic (PV) systems. The majority of commercial BESSs implement the self-consumption, rule-based approach, which aims at storing the excess of PV production, and then reusing it when the power demand of the loads exceeds the PV power generation. Even though this approach proved to be a valid solution to increase the self-consumption of distributed generators, its ability to reduce the power flow uncertainties caused by PV systems is still debatable. To fill this gap, this study aims at answering this question by proposing a dedicated set of key performance indicators (KPIs). These KPIs are used to evaluate the performance of a 13.8 kWp/25.2 kWh Lithium-Ion BESS coupled with a 64 kWp PV system. The results of the study revealed that the impact of the storage system had almost negligible effects on the uncertainty of the net power flows, while showing better results in terms of the reduction of the absolute power ramps, particularly during the BESS charge stages. These results represent an interesting point of discussion by suggesting that different storage control approaches should be investigated.