A Comprehensive Energy Management Tool for Renewable Energy Communities: Modeling PV Production, Building Demand, and Shiftable DHW Scenarios

Subsidized Renewable Energy Communities (RECs) are perceived as an effective framework to enhance the diffusion of distributed Renewable Energy solutions. This work presents a streamlined model for estimating energy balances within RECs, and applies it to a comparative case study aimed at evaluating the benefits of integrating Domestic Hot Water (DHW) as a fully time-shiftable load. An urban community based in Milan is chosen as reference for the simulations, and three REC configurations, each employing a distinct DHW management strategy, are defined. Simulation results demonstrate that electric production of DHW significantly reduces environmental impact, improves overall community self-consumption and increases the economic profitability of the REC. The best results, both from an economic and a technical standpoint, are achieved when DHW demand is fully shiftable and each building is equipped with a storage tank, as this configuration maximizes system flexibility and energy self-consumption. Finally, a sensitivity analysis, based on varying the ratio of prosumers (i.e., buildings equipped with PV systems) to consumers in the REC, shows that as more photovoltaic capacity is installed, the community becomes better at consuming its own energy locally (higher physical self-consumption). However, this also leads to a reduction in virtual self-consumption, since the surplus energy injected into the grid exceeds what other members can absorb at the same time.