Energy Communities and the Sustainable City: An Insurance-Based Framework for Monetizing Positive Externalities and Territorial Value Creation – Evidence from the PART’Extern Project

This paper presents the operational research conducted within the PART’Extern project (2023–2025), led by ECAM-EPMI in partnership with Seinergy Lab and supported by ADEME and PUCA. The project develops a structured and transferable methodology to identify, assess, and economically valorize the positive externalities produced by participatory renewable energy initiatives, with a particular focus on collective self-consumption schemes. The research bridges operational research, territorial governance, and sustainable finance through an integrated valuation framework. It resulted in (i) a methodological guide for stakeholders, (ii) a portfolio of quantified benefit sheets translating environmental and social impacts into economic indicators, and (iii) an innovative model assessing insurance-related value linked to risk reduction and enhanced territorial resilience. Findings demonstrate that making externalities visible, measurable, and economically translatable can transform intangible territorial benefits into bankable value. By strengthening financial robustness and facilitating access to public and private funding, this framework contributes to the consolidation of energy communities as long-term actors of the sustainable city. More broadly, the study advances research at the intersection of energy governance, territorial economics, and sustainable finance by proposing an operational and replicable approach to unlocking hidden territorial value.