Battery energy storage system for grid-connected photovoltaic farm – Energy management strategy and sizing optimization algorithm

Battery energy storage systems (BESS) are considered as a basic solution to the negative impact of renewable energy sources (RES) on power systems, which is related to the variability of RES production and high power system penetration. BESS can further improve the profitability of renewables, for example, by shifting energy to a higher price interval in the daily market (DM). In this study, a dedicated control strategy for PV-BESS that maximizes the DM revenue is proposed. The proposed dedicated PV energy management strategy and the incorporation of an additional control mode (bidirectional energy transfer with a power grid) to improve the system profitability indicate the novelty of this study. The algorithm for determining the control strategy was implemented using analytical methods based on complete data on PV production and energy prices. Furthermore, the control strategy was implemented in a sizing algorithm that optimized the financial criteria. The effectiveness of the algorithm was demonstrated through an example of real 1 MW PV data. A 10-year analysis of the system operation using the additional control mode indicated a significant increase in the rate of return of the energy storage, reaching 15 % for the high PV penetration price profile. •Energy distribution strategy that improves the profitability of the PV system is presented.•Proposed algorithm based on historical data provides low computational requirements.•Modified battery degradation model based on battery end-of-life is proposed.•Connection power and PV penetration affect optimal battery parameters.•High PV penetration increases system profitability.