Decarbonization of Heat Supply in Southern Europe: Strategy, Challenges, and Social Implications

This article explores the approaches to decarbonizing heat supply in the residential sectors of three Southern EU countries: Portugal, Spain, and Greece. Unlike Northern European countries, where heat supply decarbonization strategies predominantly rely on the promotion of fourth-generation district heating systems that integrate renewable heat sources, the adoption of this ‘Scandinavian model’ has been largely ineffective in the Southern European context. Among the countries analyzed, Spain is the only one that has made notable progress in developing decarbonized district heating solutions. However, the broader implementation of these systems is constrained by the low energy efficiency of residential building stocks in Southern Europe, which leads to high heat losses and discourages investment in district heating infrastructure.A critical issue exacerbating this challenge is the widespread problem of low energy performance in residential buildings, which not only reduces the feasibility of district heating but also contributes significantly to energy poverty. Higher heating costs place a disproportionate burden on low-income households, further underscoring the urgency of effective decarbonization strategies. In response, the primary approach pursued in Portugal, Spain, and Greece focuses on large-scale building renovations aimed at improving energy efficiency while modernizing individual heating systems. Supported by EU funding, these initiatives include targeted subsidies for economically disadvantaged households, ensuring that the transition to sustainable heating does not exacerbate existing inequalities.Building renovation as a decarbonization strategy is viewed as a comprehensive solution that simultaneously reduces CO₂ emissions, enhances energy efficiency, and mitigates some of the most pressing socio-economic challenges linked to energy poverty. However, the effectiveness of this approach remains contingent on sustained financial support, technological advancements, and the ability to integrate energy-efficient heating technologies at scale. The article highlights the need for policy coordination between national governments and EU institutions to create a cohesive framework that accelerates the decarbonization of the heat supply sector in Southern Europe while ensuring social equity and economic feasibility.