Decarbonisation of Estonia's residential building stock

This study analyses the climate implications of deep renovation and energy supply decarbonisation in Estonia. Employing life cycle assessment and building stock modelling through an archetype-based approach, it estimates the greenhouse gas mitigation potential of renovating the entire Estonian residential building stock by 2050, as outlined in the national long-term renovation strategy. The analysis incorporates alternative future scenarios to depict potential emissions trajectories contingent upon the effectiveness of policy implementation. The study utilises comprehensive data from the Estonian Building Registry—one of the earliest examples of a national digital twin—encompassing the whole residential building stock. The findings indicate that the complete implementation of decarbonisation strategies could reduce annual greenhouse gas emissions from the existing residential stock by up to 95 % compared to 2020. The embodied emissions from the renovation measures are minor compared to the energy savings gained. In the Estonian context, the overall success of building decarbonisation is closely tied to the carbon intensity of grid electricity. If the current fuel mix in electricity and district heating production persists, comprehensive renovation may paradoxically result in higher emissions than the baseline. While seemingly counterintuitive, this outcome is primarily attributable to the low carbon intensity of wood-based heating, which is prevalent in detached houses. Electrification of heating and installing mechanical ventilation systems increase the electricity demand. The construction of on-site photovoltaic electricity capacity can significantly contribute to the decarbonisation of the building stock in Estonia.