Benefits and allocation principles of sector-coupled energy communities

Local energy exchange can unlock synergistic potentials of variable renewables, sector-coupling technologies, and operational flexibility. Understanding the optimal operation and satisfactory cost-benefit allocation between participants is especially challenging due to the complex interaction. This work presents an open-source, operation and investment optimization model for energy communities with electricity- and heat trading. Internal payments according to competitive- and cooperative (game theoretic) principles are compared. The case study for analyzing potential benefits is a suburban town with high renewable energy potentials, residential-, and commercial participants, and technologies - e.g., generation, storage, and demand-side management. The results present a viable case for multi-sectoral energy communities, in which external costs are reduced by 23% with electricity trading, and by 33% with additional heat exchange. With the integrated operation, self-consumption of variable renewables increases by 12%. Energy import and associated emissions decrease by less than 10% as natural gas is still relevant for space heating. Nevertheless, the higher value of heat pumps paves the way for further adoption and lowering fuel imports. Every participant profits from the local exchange after the allocation. Therefore, individual rationality is preserved. However, households benefit more under a cooperative principle, whereas revenues for CHP and wind generation are higher under a competitive scheme. The findings are relevant to the policy and composition design, e.g., the marginal savings in homogeneous settings reveal the importance of inclusivity and technology openness.