Operational management of multiple energy communities in the energy market: a bilevel optimization-based approach

Increasing integration of distributed renewable energy sources necessitates a paradigm shift in power grid management. Energy Communities (ECs), incentivized by European policies, are emerging as key players in this transition by enhancing renewable energy adoption, promoting energy efficiency, and mitigating energy poverty. ECs require advanced coordination strategies to optimize their economic and technical performance, while preserving distribution grid stability and efficiency. In this paper, a novel entity (the EC aggregator), is introduced to coordinate multiple communities for efficient participation in balancing markets, specifically the Demand Response (DR). A bilevel optimization framework is proposed: the high level is a tracking problem of the DR reference power value. Instead, the low level models multiple ECs, each one characterized by different participants and an EC manager; the resulting optimization problems, one for each EC, are transformed using Karush-Kuhn-Tucker conditions. The decision model has been applied to a case study with real data from the Savona province, Italy. By leveraging distributed energy resources, storage systems, electrical vehicles and flexible loads, the proposed approach maximizes individual and collective self-consumption, while enhancing grid reliability. Results demonstrate the effectiveness of hierarchical coordination in maintaining EC profitability while providing ancillary services to the grid, thus contributing to broader sustainability objectives of modern energy systems.