Techno-Economic Case Study of a Rural Local Electricity Community in Switzerland

Abstract: Local Electricity Communities (communautés électriques locales, CEL) will become operational in Switzerland in 2026, allowing prosumers, consumers, and storage operators within the same municipality and distribution system operator (DSO) area to exchange electricity over the public grid with reduced distribution tariffs. This report examines a rural Swiss case study to explore the techno-economic implications of CELs for both participants and the local DSO. The findings indicate that CELs can enhance the local use of renewable generation, particularly photovoltaics, and offer modest financial gains, with outcomes strongly shaped by community size, composition, and tariff design. Larger and more heterogeneous communities achieve better internal matching of supply and demand, though the overall incentive remains limited because the tariff reduction applies only to distribution charges. The study further shows that internal energy exchange is maximized when local PV generation covers roughly 1-2 times the community load. For DSOs, CELs reduce grid imports (27-46%), resulting in a substantial reduction in distribution tariff revenues (17-36%), necessitating regulatory adaptation. While centralized batteries provide economic value to members, their technical impact on the grid remains modest due to their small, economically optimized capacity. Larger centralized storage is shown to reduce transformer peak power, but risks increasing line loading, suggesting a need for careful sizing and placement.