Science-based actions to support decision-making in the building sector towards carbon-neutral cities

Cities represent focal points for human civilisation, in terms of concentration of population, economic, intellectual and cultural spheres of activity. Although they cover only 2 % of the earth's surface, they host 50 % of the population, they contribute to two-thirds of the energy consumption and to 70 % of the CO2 emissions. The overall building sector, including residential, industrial and tertiary, plays a major role in terms of energy consumption and consequently of carbon emissions, producing in a typical European city, more than 40 % of the cities’ emissions. For this reason, which ever strategy of mitigation of the CO2 emissions should start targeting this sector through a set of consistent actions. In this context, characterized by a high level of complexity, it is necessary to develop simple science-based models that can be used by policymakers to design actions that are feasible in space and time. In this paper we provide a conceptual framework for the identification and definition of the possible actions and their mutual interactions in the building sector, based on data that are commonly available to city policymakers, as well as a platform that can handle such models and serve as a complete support to policy makers. The proposed approach is applied to a real European city to demonstrate its feasibility and assess its effectiveness in achieving emissions reduction targets. Results provide effective support to the municipality to set up the city action plan towards climate neutrality.