Long-term scenario for a decarbonised European energy system

In the 21st century, climate change has become a central driver of national and international decision-making, especially in matters related to energy, security, and long-term development. Among the most significant global responses is the transition towards a carbon-neutral energy system, a process that requires rethinking how energy is produced, delivered, and consumed. Europe, as one of the largest historical contributors to greenhouse gas emissions and a major economic power, stands at the forefront of this global effort. Yet the transition remains challenging due to the inherent complexity of the energy system, the mismatch between long-term climate objectives & short-term policy priorities, and the presence of geopolitical pressures.
This PhD thesis uses the TIMES-Europe energy system model to examine how Europe can navigate these difficulties and design credible long-term strategies for its overall decarbonisation effort under multiple scenarios. Through projections, this research investigates a set of plausible pathways that allow Europe to meet its climate targets under varying levels of ambition and cooperation among EU member states. The thesis is structured around five main research questions focusing on: A) How can an energy system model, like in our case TIMES-Europe, be developed and adapted to reflect and remain aligned with the most recent and constantly shifting policy priorities?; B) How may decarbonisation efforts and the associated energy transition transform European residential heating demand?; C) Which combinations of policies and technologies promote emission reductions and energy savings in Europe’s residential building stock?; D) How do EU climate policies influence the pace and distribution of the energy transition across sectors and countries in Europe, and do enacted policies match stated ambition?; and E) What role can Norway and its substantial hydropower resources play in the broader European energy transition?
The overarching findings of this work offer insights into how Europe’s energy transition can unfold under different levels of climate ambition and cooperation among countries. Strengthened efficiency and dwelling retrofitting measures consistently reduce future residential space heating needs, allowing demand to decouple from population growth in a way that yields intrinsic structural improvement. The analysis exposes a possible trade-off: rapid efficiency gains achieved under weak long-term ambition do not necessarily deliver the deepest emission reductions later, which underscores the value of policy signals that are both credible and enduring. At the system level, our results show that the EU’s current policy framework does not yet place the region on a trajectory consistent with climate neutrality, leaving residual emissions across several parts of the energy system. The thesis points out that, in order to remain aligned with the EU’s long-term objectives, Europe would benefit from stronger climate ambition to accelerate the decarbonisation of hard-to-abate sectors, as well as from deeper cooperation among EU member states to enhance system-wide efficiency through shared targets and coordinated action.
Amid the complexity of climate change control, one insight carries particular weight for policymakers: climate ambition and cooperation between countries function as mutually reinforcing pillars of a successful transition. When countries sustain long-term commitments, support each other’s technological progress, and share responsibilities in ways regarded as fair, the energy transition becomes more than merely a simulated pathway; it becomes a credible, resilient, and enduring project capable of shaping Europe’s future.