Swiss parliament votes to lift nuclear ban, triggering referendum fight over energy future

The parliamentary vote

On Thursday the Nationalrat, the lower house, followed the Ständerat and approved a government proposal to lift the ban on constructing new nuclear power plants. The final vote in both chambers was set for Friday, after a dramatic reversal: on Monday the same chamber had sent the bill back to the government by a vote of 100 to 97, with two abstentions. On Thursday the result flipped to 100 to 98 in favour of the nuclear advocates.

“The nuclear power plants are not up to date! Right now the geopolitical situation shows how problematic new dependencies are. Uranium is imported, including from countries like Russia.”

Referendum is almost certain

The left-leaning parties and environmental groups immediately announced a referendum. They need 50,000 signatures to force a popular vote, and Green Party president Lisa Mazzone said the alliance of 31 organisations is confident of reaching that number. The vote is expected in early 2027, ahead of the next federal elections.

“For us Greens, this will be the vote of the decade.”

Why the ban is being lifted

In 2017, Swiss voters approved an energy law that prohibited new nuclear plants, and the ban took effect in 2018. Four aging reactors still operate; Beznau 1 and 2, one of which is the world's oldest running reactor, are to close in 2032 and 2033. The government argues that slow progress on solar and wind expansion, combined with energy security worries after Russia's invasion of Ukraine, makes a nuclear option necessary. Energy Minister Albert Rösti insisted that no concrete projects exist and the decision only keeps the door open.

Cost and investment doubts

Opponents point to enormous costs. The Axpo energy company, in one scenario, estimated over CHF 50 billion for two new reactors. Michael Frank, director of the electricity industry association VSE, told SRF that a new plant could cost up to CHF 13 billion, a sum that would likely require state guarantees and foreign investors. Meanwhile, the WWF called the decision a risky mistake that undermines a cheap, safe and renewable energy supply.

“For such a sum, Swiss pension funds and capital providers alone would probably be overwhelmed. You would have to bring big banks and foreign investors on board.”

A narrow win amid pressure claims

The one-vote margin was shaped by a single absent lawmaker and three members who switched sides. Green MP Sibel Arslan and others accused the right-wing SVP of improperly pressuring Daniel Sormanni, who belongs to the MCG party but sits with the SVP faction. Video showed faction leader Thomas Aeschi and several senior SVP figures speaking with Sormanni for minutes on the floor. Afterward, he changed his earlier abstention to a vote against sending the bill back.

“The pressure from the SVP leadership was too much.”

“That is unconstitutional and extremely problematic in terms of democratic policy.”