Heat Transition and Decarbonization in the German Building Stock: Insights on Energy Vulnerabilities in Northern Germany

Mathias Hehle, Elisabeth Endres

Achieving climate neutrality by 2045 requires a fundamental transformation of the German building sector, where residential heating accounts for more than 65% of final energy consumption and remains largely dependent on fossil fuels. Despite increasing regulatory pressure, renovation rates remain insufficient to meet decarbonization targets. While existing research predominantly focuses on technical solutions, spatial and socioeconomic dimensions are often underrepresented. This paper develops a spatially explicit and socio-technical framework to analyse urban heat transition pathways using two representative urban districts within the city of Braunschweig as case studies. Building-level energy demand, renewable energy potentials, and greenhouse gas emissions are modelled using scenario-based simulations. Decarbonization pathways include heat pump deployment, district heating expansion, photovoltaic integration, and deep renovation strategies. In addition to technical performance indicators, socio-economic data such as income distribution, tenancy ratios, and household characteristics are integrated into the analysis. This enables the identification of spatial patterns of energy vulnerability and the assessment of distributional impacts of heat transition strategies. The results reveal clusters of high-emission building typologies and socially vulnerable populations, highlighting areas where decarbonization measures can achieve both emission reductions and social co-benefits. At the same time, potential conflict zones emerge where rapid transitions may exacerbate social inequalities. The proposed methodology supports evidence-based and socially balanced urban energy planning and contributes to bridging the gap between spatial energy system analysis and the assessment of social vulnerability in urban decarbonization processes.