Three-Stage Peer-to-Peer Coordination for Multi-Microgrids: Rolling Alternating Direction Method of Multipliers Dispatch and Environmental Contribution-Weighted Nash Settlement

Peer-to-peer (P2P) energy trading and shared energy storage (SES) are effective means for multi-microgrid systems to improve operational flexibility, but the cooperative surplus they create must be allocated among participants with heterogeneous carbon responsibilities. However, existing allocation mechanisms determine bargaining power mainly by trading volumes or costs, and most low-carbon dispatch studies internalize carbon costs into the dispatch objective, conflating physical efficiency with fairness of allocation. To address these issues, this paper proposes a three-stage P2P coordination framework for multi-microgrids, comprising day-ahead planning (Stage I), intraday rolling dispatch (Stage II), and ex-post settlement (Stage III). In Stages I–II, a unit-commitment-economic-dispatch decomposition keeps the commitment decisions centralized while the continuous dispatch is optimized in a fully distributed manner, which preserves both optimality and peer privacy. Within the rolling alternating direction method of multipliers (ADMM) dispatch, dimension-grouped consensus penalties and a dual warm-start chain keep each hourly window tractable under forecast errors. In Stage III, an environmental contribution metric capturing both the scale and cleanliness of self-generation is defined, and an asymmetric Nash bargaining solution weighted by the metric is derived in closed form. Case studies on a four-microgrid system with SES over twelve operating days across four seasons show that the cooperative surplus reaches 1012.37–2668.37 RMB/day, i.e., 6.2% to 39.7% of standalone costs. The distributed rolling dispatch reproduces the centralized optimum of every hourly window within a relative deviation of 5.4×10−3, and under 10% day-ahead and intraday forecast errors, the executed costs stay within 0.84% of the perfect-foresight bound, with budget balance and individual rationality holding on all twelve days. The framework thus provides carbon-responsibility fairness as an auditable settlement layer without distorting the physically efficient dispatch.