Should we forge ahead with the existing energy strategy or return to building new nuclear power plants again in the future? Since the Federal Council’s counter-proposal to the “Blackout Initiative”, this question has been at the heart of Swiss energy policy and will ultimately be decided on by the Swiss electorate.
A new study by 19 energy experts from ETH Zurich and the Paul Scherrer Institute (PSI) is investigated under which conditions the construction of new nuclear power stations may make financial sense for Switzerland’s future energy system. The findings of the study are based on four different energy models. These models calculate which technologies Switzerland could use by 2050 to cover significantly higher electricity demand as cheaply possibly and in a carbon-neutral way.
Speaking on behalf of the research team, André Bardow, Professor at ETH, explains: “Each of these models is based on a range of assumptions that are associated with uncertainties and simplify the complexity of the energy system. In cases where these models point in the same direction, there are robust findings that could form the basis for discussion by society and in the sphere of politics. As for whether to decide for or against nuclear power, this is ultimately a question for society.”
Nuclear power under present political conditions
The study by PSI and ETH researchers shows that new nuclear power plants might not be financially viable under present fiscal conditions. Proceeding on the assumption that the state will continue only to subsidise renewable electricity sources such as photovoltaics and wind as part of its target to expand power generation to 45 TWh in future and not provide any funding for the construction of new nuclear power plants, nuclear power would still be too expensive under the majority of model calculations used in the study. This remains the case even with low to moderate construction costs of CHF 5,000 to CHF 8,000 per kW of installed capacity.
The study also shows that Switzerland can achieve its net-zero target using existing and planned technologies without the need for new nuclear power plants. Efficient electricity trading with foreign countries is among the essential factors for the stability of a system that does not include nuclear power. Depending on the model, the net electricity imports in winter range between 5.4 TWh and 12.4 TWh. All models show that Switzerland would still be just as dependent on net imports in winter in 2050 as it is today. For example, Switzerland imported around 7 TWh of electricity net between October 2025 and March 2026, when Gösgen Nuclear Power Plant had been powered down to undergo an inspection. By way of comparison, Beznau and Leibstadt nuclear power plants generate around 6 and 10 TWh of electricity per year respectively.
In a future energy system without nuclear power, solar energy would supply between 36 and 43 TWh of electricity depending on the model, which would cover around 50 percent of total energy consumption in 2050. Taken together, hydropower and photovoltaics would make up around three quarters of the electricity supply, thus forming the backbone of the system. Other additions would include wind power, biomass, and storage technologies such as pumped-storage power plants, chemical energy storage plants (hydrogen and methane) and batteries. In order to hit the expansion targets for these generation and storage technologies, government support is required. The Swiss electorate accepted the statutory basis for this support in 2024.