Optimizing decarbonization in the EU building stock: a interoperable framework tailored to end users needs

The global shift towards sustainability and energy efficiency has significantly influenced the building sector, which plays a critical role in energy consumption, greenhouse gas emissions, and the depletion of natural resources. This is a key driver behind the European Union’s push for decarbonizing the building stock, through the introduction of concepts like Nearly Zero Energy Buildings (nZEBs) and Zero Energy Buildings (ZEBs), presented in the current version of the Energy Performance of Buildings Directive (EPBD). This thesis introduces a versatile and adaptable tool designed to optimize building energy performance and reduce carbon emissions. It integrates easy end-user access and results visualisation, compliance with current European Union regulations, while offering a practical and platform-interoperable application channeled towards a Building Information Model (BIM) environment. Through this approach, the tool addresses a range of issues spanning societal, technological, research, and policy-related challenges. By em-ploying a multi-stage, multi-objective optimization process powered by the Non-dominated Sorting Genetic Algorithm II (NSGA-II), it efficiently tackles conflicting objectives related to heating and cooling needs, overall energy demand, and carbon emissions. The first stage of the process optimizes the building envelope parameters represented by the thermal transmittance, in order to reduce thermal energy need. The second stage focuses on minimizing CO2 emissions by optimizing the efficiency of the building technical systems, with the addition of renewable energy sources. The integration of a two-stage process ensures that the optimization reflects both energy and environmental performance, while maintaining flexibility in addressing user-specific needs. Compliance with the current European standard framework is guaranteed by the implementation of an Excel file that performs the energy simulation in accordance with UNI 52016, adhering to the most recent update of the EPBD, dated May 2024. A key feature of this research is its adaptability to different legislations, while guaranteeing straightforward implementation for the end users, such as engineers, architects and technicians. Automation and interoperability between different platforms are fundamental for this purpose. The tool’s design allows easy modifications, making it adaptable for evolving energy standards across Europe. The algorithm was tested and validated through a case study, represented by Manifattura Tabacchi in Turin, Italy. This application demonstrates how the tool can be applied in real-life settings, offering practical solutions that balance energy performance with environmental impact. In the future, the tool can be further developed, with the objective of providing even more information and adapting it to include thermal comfort, cost-optimality, Life Cycle Assessment (LCA) and other building-related central aspects. By providing a range of near-optimal solutions, this approach provides support for design decision-making, particularly in the context for building retrofits, thus promoting long- term sustainability. This thesis contributes to the development of an adaptable, regulation-compliant and interoperable tool that is designed to assist building professionals in achieving decarbonisation aiming at a nZEB or a ZEB, as outlined in the last version of the EPBD.