Novel Nuclear Technologies

Switzerland aims to decarbonize its energy supply while prioritizing security of supply in recent years due to geopolitical events. After Fukushima in 2011, the Federal Council and Parliament decided to phase out nuclear power, confirmed by a 2017 public vote banning new plant construction. However, political and public debate about nuclear’s future has re-emerged amid potential electricity shortages and uncertain import opportunities. At the same time, rising electricity demand from e-mobility, heat pumps, and energy-intensive AI systems is adding further pressure to the system.

In this context, TA Swiss has commissioned a study to investigate the opportunities and risks of new nuclear technologies in Switzerland. The study is conducted by a consortium led by the Paul Scherrer Institute (PSI) together with ETH Zurich, ZHAW, the University of Bern, the Stiftung Risiko-Dialog, and the Greek modelling firm E3 Modelling. It takes an interdisciplinary approach addressing relevant technical, social, political, economic, and legal issues.

The research is structured around four thematic work packages. The technology assessment evaluates reactor concepts potentially relevant for Switzerland, including large, water-cooled reactors and Small Modular Reactors (SMRs), with respect to safety, maturity, costs, fuel cycles, and environmental impacts across their full life cycle. The energy system analysis uses the Swiss TIMES Energy System Model (STEM) and a macroeconomic general equilibrium model (GEM-E3-CH) to assess how nuclear energy could contribute to Switzerland's net-zero target by 2050, including its role in sector coupling, winter supply security, and broader economic effects such as employment and GDP. The societal and political analysis draws on population survey data and a participatory stakeholder workshop to examine public acceptance, risk perception, and the conditions under which established positions might shift. Finally, the legal assessment examines whether Switzerland's existing regulatory framework, in particular the Nuclear Energy Act and ENSI guidelines, currently designed for Generation II/III light-water reactors, is compatible with new technologies and what legislative adaptations might be required.

The central output of the study is a comprehensive report that synthesizes key findings across all dimensions described above. Furthermore, it outlines the prerequisites, timelines, and measures needed for a potential integration of new nuclear technologies into Switzerland's future energy system. Finally, it recommends options for actions and provides a factual basis for informed public and political debate.

TA-Swiss

• PSI Laboratory for Energy Systems Analysis
• ETHZ Laboratory of Nuclear Safety and Multiphase Flows
• University of Bern Institute of Political Science
• Stiftung Risiko-Dialog
• ZHAW Institute of Regulation and Competition
• E3-Modelling (E3M)