Solar PV sharing in urban energy communities: Impact of community configurations on profitability, autonomy and the electric grid

Abstract

• Comprehensive analysis of 75 energy community (EC) configurations with real-world data • Community size irrelevant for prosumer profitability and community self-sufficiency • Community size, PV capacity and penetration relevant for the grid impact of the EC • Max. self-sufficiency rate (37.8%) declines to 33.3% when considering grid impact • Identification of EC configurations that maximize KPIs and avoid grid upgrades Through a deterministic techno-economic analysis based on high-resolution real-world demand data from 3,594 households, we analyse how the configuration of a solar energy community (EC) impacts its economic and technical performance. We find that prosumer ratio and PV capacity, but not community size, affect prosumer profitability and EC self-sufficiency rate (SSR). The profitable prosumer share in an EC falls below 25% as the prosumer ratio increases beyond 30% for PV systems sized to meet annual demand (M-sized) and 50%, respectively, for systems sized to meet twice the annual demand (L-sized) due to economies of scale. The SSR steadily increases with prosumer ratio and PV capacity to a maximum of 37.8%. However, all three EC design dimensions influence the grid impact. In the absence of energy storage, this imposes a permissible range on the prosumer ratio to avoid grid upgrades- 60-100% and 30-50% for M- and L-sized systems, respectively, which in turn limits the SSR to 29.4-33.3% and 28.2-33.1%. The results establish clear configurations that strike a good balance between different performance metrics of an EC. EC planners, policymakers, and grid operators can build on these results as rules of thumb to incentivize EC formation while maximizing welfare for all stakeholders.