FAQ

Four nuclear power plants are in operation in Switzerland:

• Beznau-1 (pressurised water reactor) since 1969, 
• Beznau-2 (pressurised water reactor) since 1971,
• Gösgen (pressurised water reactor) since 1979,
• Leibstadt (boiling water reactor) since 1984. 

The Mühleberg nuclear power plant (boiling water reactor), which began operation in 1972, was shut down in 2019 and has been undergoing dismantling since then.

The Nuclear Energy Act (KEG) does not provide for any lifetime limits for nuclear power plants. A nuclear power plant may be operated as long as it meets the legal safety requirements. The operator is responsible for the safety of its plant. The supervisory authority, the Swiss Federal Nuclear Safety Inspectorate (ENSI), monitors the plants on an ongoing basis, determines possible adjustment measures and their implementation and can also order a shutdown if safety is no longer assured.

Over the long term, the funds have performed in line with the target amount defined by the authorities. Thanks to the five-yearly cost studies, the adjustment of the annual contributions paid by the owners of the nuclear facilities as required and a responsible investment strategy, they are on track.

The cost studies are carried out with due caution and to the best of our expertise and in light of current knowledge. This also includes assumptions about the timing of future costs and the estimation of any risk-related costs. The inevitable uncertainties in forecasting are also taken into account in the estimate. All these cost estimates are supported by the fact that the level of technical knowledge and international experience in decommissioning and waste disposal projects is constantly growing. The uncertainties, on the other hand, are steadily decreasing. Furthermore, the cost studies are updated every five years. The cost risk therefore becomes smaller and smaller over time.

If unforeseen additional costs nevertheless arise, the owners of the nuclear facilities bear the risk. If one owner becomes insolvent, the other owners are required by law to make additional contributions. The government is at the end of the five-tier-cost-bearing cascade. Only when these additional contributions are not economically viable for an owner does the Federal Assembly decide whether, and to what extent, the federal government should contribute towards the costs.

The funds' payment plan is based on an assumed period of operation of 50 years for the nuclear power plants.

In the event of the early permanent decommissioning of a plant, the owner will, when calculating the contributions from 2024 onwards, be treated in the same way as if it had decommissioned the plant after 50 years of operation: the contributions will be spread over 50 years. The owners must cover the total of the calculated decommissioning and disposal costs through their contributions, regardless of the plant's period of operation and the amount of energy produced.

The investment strategy is determined by the commission of the two funds appointed by the Federal Council, based on the requirements of the Decommissioning and Waste Disposal Ordinance (SEFV). Since 2020, the SEFV has stipulated an average real return of 1.6% per year as the basis for calculation. An operating life of 50 years is assumed for the nuclear power plants.

Investment activities are monitored on an ongoing basis by the Commission's Investment Committee, which is made up of financial experts appointed by the Confederation and those of the owners and is supported by an investment controller. The annual financial statements of the funds are also audited annually by an external auditor and published publicly.

The two funds are geared towards an extremely long-term investment horizon, as payments are only made once the nuclear power plants have been definitively decommissioned.

A limited operating time for nuclear power plants:

• reduces the incentives for comprehensive, long-term retrofitting;
• makes personnel planning more difficult;
• leads to claims for compensation, since existing assets are withdrawn and the investments made can no longer be recouped.

In particular, a time limit means:

• no increase in safety,
• a threat to grid stability, because the stabilising effect of nuclear power plants is lost.

Thanks to careful and extensive retrofitting, Switzerland's nuclear power plants have almost reached the safety standards of new plants - an outstanding track record by international standards. The Swiss Federal Nuclear Safety Inspectorate (ENSI) is required by law to carry out regular inspections of the condition of the facilities and can at any time order retrofitting measures or even the temporary decommissioning of the facility if there are any doubts about safety.

The proof of safety required for long-term operation is regulated by the Swiss Federal Nuclear Inspectorate (ENSI). The following points, among others, are set out in the corresponding directive:

• Comprehensive proof of safety must be provided for nuclear power plants that are to be operated for longer than 40 years. This verification must be updated at least every 10 years and should be provided as part of the periodic safety review (PSR).
• As part of the retrofitting plan, the operator must explain the measures it is taking to ensure the safe operation of its facility beyond 40 years.

• Open-ended licences lead to continuous retrofitting.
• Open-ended licenses encourage a mindset of constant questioning. Every nuclear power plant must be safe for the long term at all times.
• Open-ended licences favour staff development and the recruitment of new staff.

Yes, because safety is at the heart of this system. The protection of people and the environment through safe nuclear facilities is a concern shared by all. The recognised high level of safety at Swiss nuclear power plants is based on:

• a robust and state-of-the-art power plant design;
• the responsible operation by qualified personnel;
• a reliable, stable and consistently implemented 

Swiss nuclear energy legislation does not provide for any lifetime limits for nuclear power plants. However, an unlimited operating license does not mean unlimited operation. A nuclear power plant may be operated as long as it meets the legal safety requirements. The operator is responsible for the safety of its plant. The supervisory authority, the Swiss Federal Nuclear Safety Inspectorate (ENSI), monitors the plants on a permanent basis and can order a shutdown if safety is no longer assured.

Yes, in US and Belgium, for example, limits on the period of operation of nuclear power plants are dictated by policy.