Identifying and analysing important model assumptions: Combining techno-economic and political feasibility of deep decarbonisation pathways in Norway

Understanding the political feasibility of transition pathways is a key issue in energy transitions. Policy changes are a significant source of uncertainty in energy system optimisation modelling. Energy system models are nevertheless continuously being updated to reflect policy signals as realistically as possible. Using the concept of transition pathways as a starting point, this cross-disciplinary study combines energy system optimization modelling with political feasibility of different transition pathways. This combination generates insights into key political decision points in the ongoing energy transition. Resting on actor support structure and political feasibility of four main pathway categories (electrification, hydrogen, biomass, and energy efficiency), we identify critical model assumptions that are politically significant and impact model outcome. Then, by replacing the critical assumptions with technical limitations we model a scenario that is unrestrained by assumptions about policy, we identify areas where political choices are key to model outcomes. The combination of actor preferences and modelled energy system consequences enables the identification of future key decision points. We find that there is considerable support for electrification as the main pathway to net-zero. The implications of widespread electrification, in terms of energy production and grid capacity, lead us to identify challenging policy decisions with implications for the energy transition.