A bilevel framework for shared PV-storage configuration and P2P trading in the building cluster

Shared photovoltaic (PV)-storage planning in building clusters must coordinate physical sizing, peer-to-peer (P2P) trading, network feasibility, and participant-level payoff acceptability. This paper proposes a participation-constrained Planning-Configuration and Transaction-Allocation (PCTA) framework for shared PV-storage planning. The planning-operation layer maximizes expected community welfare under PV-load scenarios, shared-storage operation, degradation cost, rule-based P2P clearing, and distribution-network limits. The allocation layer distributes cooperative welfare through contribution-weighted asymmetric Nash bargaining (ANB), using standalone PV-storage operation as the economic disagreement benchmark. A five-building annual campus case and a 20-user mixed-use stress case are used for validation. In the campus case, PCTA-ANB improves annual net cash flow by 20.75 × 10³ yuan/year relative to individual PV-storage operation and installs 144.21 kWh/74.38 kW of shared storage. Grid import and export decrease by 21.20% and 20.35%, respectively. The welfare-only allocation gives Gym E a payoff 13.02 × 10³ yuan below its standalone benchmark, whereas ANB restores positive individual-rationality margins for all participants. Coalition screening identifies seven potential deviation coalitions, showing that payoff acceptability and coalition stability require separate verification. In the 20-user stress case, the copper-plate dispatch causes 181.82% transformer and line loading; embedding feeder constraints eliminates violations with a 3.32% cost increase and 0.431 GWh/year PV curtailment. Electric-vehicle charging, vehicle-to-grid operation, high-power-load, and participation-availability tests show that flexibility value and storage sizing are conditional on resource location, network constraints, and active participant composition.