Optimal PV Design for Collective Self-Consumption in Italian Residential Energy Communities

The increase in local Renewable Energy Sources (RES) production is one of the mainstream topics for promoting a more sustainable energy future. The Revised Renewable Energy Directive (RED III) has, in fact, specifically placed strong emphasis on local and decentralized renewable energy production, binding the EU renewable energy target to at least 42.5% by 2030. In this context, PV-based Renewable Energy Communities (REC) can assume a relevant role in promoting local electricity production and consumption in residential buildings, bringing also sector-coupling solutions (e.g., electrification of space heating demand). This highlights the need for an optimal design of RES installation to better exploit the match between demand and consumption. The best PV size and orientation (i.e., tilt and azimuth) are, in fact, strongly influenced by the aggregated building load profile as well as by its economic sustainability. In this light, a multi-objective analysis is proposed to identify a compromise solution capable of improving self-consumption and self-sufficiency while reducing the Levelized Cost of Electricity (LCOE) for the PV. The methodology integrates a data-driven approach to capture the variability of solar irradiance across different module tilt/azimuth positions and across different longitudes and latitudes. This integration enables the analysis from a spatial perspective where buildings are supposed to be located over a regular grid of the region being studied. The results show a possible benchmark for the PV sizing of the Collective Self-Consumption scheme in Italian multi-family residential buildings. A scenario including the integration of a heat pump for space heating is also considered to highlight how the PV design is affected by a different load profile.