A Techno-Economic Comparison of a Reference Energy Community Across European National Legislative Frameworks

Renewable energy communities are gaining importance as instruments for integrating decentralized renewable generation and enabling local flexibility provision. However, systematic comparisons of community performance under varying technical configurations and regulatory conditions remain scarce. This study combines a semi-structured literature review on system-level contributions of local energy systems with a quantitative techno-economic simulation of a reference urban energy community. The community—comprising eight apartment buildings equipped with rooftop photovoltaics, battery storage, electric vehicles, and heat pumps—was analyzed across 16 scenarios varying photovoltaic capacity, electric vehicle charging optimization, and energy-sharing incentives under four European regulatory frameworks (Germany, Austria, Spain, and Italy). Photovoltaic capacity emerges as the primary driver of energy autonomy, covering 16.3–30.8% of total community demand. Optimized electric vehicle charging significantly reduces grid dependency for vehicle loads (40.0–92.7%). Energy sharing contributes modestly to total consumption (0–3.4%) but substantially redistributes financial benefits among participants. Total community costs range from 23.6 k€ to 103.3 k€ across scenarios and countries, reflecting strong regulatory influence. The findings demonstrate that effective policy support requires coordinated design across sharing incentives, network tariffs, and flexibility pricing rather than isolated instrument deployment.