Comparison of virtual energy sharing schemes for renewable energy communities under European regulations: A mixed-use case study in Italy

The Renewable Energy Directive (RED II) introduced Renewable Energy Communities (RECs) as a mechanism to empower local actors in the energy transition through collective renewable energy sharing. European Member States have transposed RED II into diverse regulatory frameworks and incentive schemes, leading to different approaches to electricity sharing. This study analyses the techno-economic performance of a mixed-use REC composed of a university campus and a residential district, using City Energy Analyst to simulate six scenarios combining two virtual energy sharing schemes, Virtual Self-Consumption (VSC) and Virtual Net Metering (VNM), and three ownership configurations, ranging from a centralized external producer to a distribution of prosumers. Sensitivity analyses on PV sizing and electricity market prices are also performed. Results show that VSC schemes achieve higher energy performance than static VNM schemes due to more effective matching between generation and demand, while economic outcomes remain comparable across schemes. Compared to the baseline, energy sharing increases self-consumption by up to 35% in VSC schemes and up to 25% in VNM schemes, with revenue increases of up to 20% under both schemes. Configurations involving non-residential prosumers improve selfconsumption and enable higher PV penetration without a proportional loss in economic viability. At the same time, economic performance is largely driven by accounting rules, including incentive tariffs and market price structures, which can offset differences in energy performance between sharing schemes. These findings suggest that REC design should prioritise the integration of non-residential prosumers, while regulatory frameworks should align economic incentives with energy efficiency objectives.