TOWARDS THE DECARBONIZATION OF THE EU BUILDING STOCK: AN INTEGRATED BUILDING STOCK RENOVATION MODELING APPROACH

In Europe, the residential building stock is responsible for about 40% of the energy demand and about 36% of the CO2 emission at global level. Considering that almost 70% of the existing building stock will still be used in 2050, a long-term vision is needed to align with future challenges to avoid having significant increases in carbon emissions. The European policymakers have a long-recognized potential energy saving associated with the renovation of the existing building stocks, as demonstrated by the directives on the Energy performance of buildings (EPBD), introducing also the need to developed an integrated buildings design approach with environmental analysis. The purpose of this thesis is to provide a comprehensive assessment of the existing building stock that could be renovated. The basis of a good renovation strategy is establishing an accurate understanding of the building stock, including age, building typology, heating source, etc. A detailed bottom-up breakdown by building type, age, energy carrier, climatic zone, energy performance, occupancy, and ownership are developed to underpin subsequent steps in the European decarbonization strategies in the residential sector. In this thesis, the energy and environmental effects of four possible renovation scenarios are studied using the dynamic energy simulation and the Life Cycle Assessment. Also, to account for the possible use of bio-based materials, a sensitivity analysis is performed on the improvement of the building’s envelope for four types of materials (as stone wool, wood wool cement board, cellulose fiber, and cork slab). Another two scenarios are relative to the installation of renewable energy systems (RES) as a solar thermal collector and photovoltaic systems. In particular, in some countries, the results show how the use of insulation materials could require less time for repaying the environmental impacts generated during their whole life cycle that the RES, comparing the environmental impacts generated during their production with the potential energy saving during their use. The models developed to allow to evaluated energy and environmental effects of a greater number of renovation strategies, highlighting the needs of an integrated approach for helping the policymakers, the designer and the engineering into the definition of the most sustainable solutions for EU-28.