Impacts of grid-scale battery systems on power system operation, case of Baltic region

Grid stability can be affected by the large-scale utilisation of renewable energy sources because there are fluctuations in generation and load. These issues can be effectively addressed by grid-scale battery energy storage systems (BESS), which can respond quickly and provide high energy density. Different roles of grid-scale BESS in power systems are addressed, following optimal operation approaches classification. Furthermore, integrating BESSs into distribution grids is discussed to manage challenges from distributed generation. BESSs aid in voltage control, enhance frequency regulation, and offer black-start services. Aggregating distributed BESSs can provide ancillary services and improve grid economics. For consumers, BESSs optimise energy costs, enhance reliability, and support self-consumption from renewables. Novel BESS services include congestion relief, system adequacy, and power quality enhancement. Moreover, the ancillary services provided in different European countries through BESS are analysed. Finally, a case study was conducted among three Baltic DSOs to analyse the required amendments to Grid Codes and Electricity Market Acts for the integration of grid scale BESS.