Integration of battery energy storage systems in renewable energy communities: Optimal configurations and strategies

This study analyses the optimal integration and sizing of battery energy storage system in energy communities. Three different configurations are considered, differing in battery placement, incentive schemes, and investment models. The configurations are selected according to Italian regulatory constraints. A Python-based tool was developed to perform quarter-hourly simulations and solve an optimization problem for sizing production systems and battery storage. A sensitivity analysis was carried out on battery cost, incentive tariff, electricity price, photovoltaic system and battery efficiency, and hourly load profiles. Results show that centralized configurations, in which generation and storage assets are shared among community members, provide several advantages. They increase renewable energy penetration, allowing larger PV capacities (+46/51%) compared to the aggregation of individually sized prosumer systems resulting in +52% of CO 2 savings. They also reduce battery requirements (up to 14%), although the overall contribution of storage remains limited when driven by economic optimization. Shared energy increases from 107 to 422 MWh/year in centralized scenarios. From an economic perspective, NPV increases from 330 to 631 k€ and payback periods are reduced up to 3.9 years. In addition, centralized configurations exhibit greater resilience to electricity price fluctuations and more effective management of demand variability, especially when users with complementary load profiles are aggregated. Economic performance is mainly driven by electricity price (with a 20% variation capable of altering profitability by up to 50%) and PV efficiency, while battery costs, incentives, and load variations play a secondary role.