Fairness-Constrained Coordination of Distributed PV and Battery Storage in Grid-Connected Energy Communities: A Seasonal Assessment

Coordinating distributed photovoltaic (PV) generation and battery storage can improve local renewable utilization. However, the schedule that produces the lowest total operating cost may not benefit all participants equally. Aggregate indicators can also conceal seasonal grid dependence. This paper develops a season-aware co-optimization framework for battery dispatch and local energy sharing in grid-connected energy communities, combining economic efficiency and distributive fairness with a seasonal assessment of energy autonomy. Evaluation covers 6576 hourly intervals from January to September 2024 for a 100-user subset of a Norwegian Energy-Community Dataset, including 87 residential and 13 commercial users. Five counterfactual scenarios distinguish standalone operation, sharing, private batteries, coordinated sharing and storage, and fairness-constrained coordination. A monthly two-stage ε-constraint formulation first minimizes community operating cost, then maximizes the minimum normalized user saving relative to private-battery operation, subject to individual no-harm constraints. Unconstrained coordination reduces cost, grid imports, and exports by 4.7%, 7.5%, and 82.7%, respectively, relative to standalone operation. With an allowable fractional increase above the minimum community-cost value of 0.5%, the fairness-constrained solution retains a 4.6% saving against standalone operation, costs 0.06% more than the unconstrained optimum, and keeps every user’s monthly bill at or below their private-battery benchmark. PV self-consumption reaches 89.3%, while load self-sufficiency is 14.1%. This divergence is strongly seasonal: in the observed winter months, nearly all PV is used locally, yet scarce generation supplies only 0.35% of demand; summer self-sufficiency reaches 38.8%. Increasing ε to 1% and 2% gives almost negligible additional fairness, identifying that 0.5% is the preferred fairness–efficiency compromise. Coordinated sharing can therefore outperform private-battery operation while enforcing monthly participant protection at little additional community cost.