Decision Support for Energy Transition : Application of Multi-criteria Decision Making on Danish Residential Heating

Abstract: With the increasing awareness of the impact of climate change, there has been more intention to reduce greenhouse gas emissions and achieve carbon neutrality targets. However, as one essential element for human well-being, residential heating remains a major contributor to global greenhouse gas emissions. The complex, interdependent, and sometimes contradictory nature of factors influencing residential heating choices makes it a difficult problem to address. Multiple actors with different goals and priorities further complicate the decision-making process. Moreover, given the current energy crisis, selecting an appropriate heating system for residential areas has become even more crucial. Therefore, there is a need for decision support tools that can consider multi-dimensional factors and heating alternatives, which usually have a long-term impact involved in residential heating choices.  Thus, this thesis aims to improve the understanding of what influences decisions to choose a heating technology alternative and how decision support tools can sup-port these decisions. Among the decision-making techniques, multi-criteria decision-making (MCDM) methods have been chosen because they are capable of considering a wide range of factors and are simple to understand and use, taking into account data availability and capability. A systematic literature review is conducted to understand the criteria and MCDM methods commonly used in the field. Two appended papers applied different approaches of MCDM methods to support the Danish residential heating transition. These applications also act as case studies to address the research questions.   This thesis highlights financial, technical, and environmental factors for decision-making on heating technologies and addresses common problems that might occur during the decision-support process. Specifically, it suggests considering financial costs, environmental emissions, technical efficiency and lifetime when choosing a heating technology and using distance-to-ideal MCDM combining other methods. Furthermore, the thesis reflects on the complexity of MCDM applications in decision support and presents a publicly available online decision support tool based on the research (https://api.flexsus.org/MCDM). This thesis contributes to knowledge for academics and fills gaps in residential heating decision-making. For practitioners, a useful tool is provided for improving the quality of decision-making in residential heating, offering a practical and scientific perspective for making informed decisions without consuming extra resources. By increasing the under-standing of influencing factors and decision-support methods for heating technologies, this thesis helps facilitate the heating transition.