Multiple-scale distributed PV potential penetration in a densely populated city: A case study of Grand Paris metropolis

Urban sustainability is a critical challenge for climate action, and increased photovoltaic (PV) production is expected to help meet this challenge. However, due to the variable nature of PV, its integration adds complexity to grid management, requiring careful consideration of the energy balance. This study addresses the challenges of energy transition and urban sustainability in densely populated cities through a case study of rooftop photovoltaic (PV) integration in the Grand Paris metropolis. Focusing on energy balance metrics such as self-consumption rate (SCR) and self-sufficiency rate (SSR), the research explores the benefits of distributed PV installations across residential and commercial sectors. Using hourly electricity consumption profiles and PV generation data, the analysis evaluates the impact of energy-sharing schemes within and across urban subregions (city center and semi-urban periphery) and between sectors. The results show that, over an extended scope, cross-sector energy sharing can improve SCR and SSR by up to 6.5% across sectors and 10% across geographical subregions. 3.19 TWh of regional residential consumption and 0.44 TWh of commercial consumption could be covered by PV, accounting for 22.4% of the total for both sectors. The periphery benefits significantly from increased SSR, linked to lower building density and higher PV capacity. Economically, rooftop PV reduces energy costs most in peripheral regions, with expanded energy-sharing perimeters enabling additional savings for central areas. These findings suggest that broader energy-sharing frameworks in metropolitan areas can optimize PV utilization, enhance grid stability, and contribute to resilient, sustainable urban energy systems. • A multi-scale electricity supply–demand balance analysis of urban rooftop PV. • Hourly real-time data is used to enable sector-specific geographical downscaling. • Energy-sharing is assessed within and across city center and semi-urban areas. • Energy-sharing improves both SCR/SSR by up to 6.5% across sectors, 10% across subregions. • PV could cover 3.19 TWh residential, 0.44 TWh commercial, or 22.4% of total use.