A raft of nuclear power station closures have condemned France for two years of low output at the height of the European energy crisis, the country’s state-owned electricity company has said.
EDF is forecasting annual output below historic typical levels until 2024 as it grapples with maintaining its aging fleet.
It means lower power supplies available for France but also for neighboring countries including the UK, which typically need to import some power from France to help meet their own needs.
It comes as countries across Europe are grappling with the shift to using more wind and solar power, which are intermittent, as well as the loss of Russian gas supplies.
Lower nuclear output this year has already contributed to surging power costs in Europe and the UK, as well as concern over blackouts.
Peter Osbaldstone, European power analyst at Wood Mackenzie, said: “France’s position in Europe means that if you lose terawatt hours from France, all of your neighbors feel that as well.”
He added that lower nuclear output increases reliability on gas in the short term, as gas-fired power plants are needed to help balance electricity supplies.
Plant outages due to corrosion and scheduled maintenance have already severely dented France’s nuclear output this year.
EDF delayed the restart of four nuclear reactors on Monday, with its Penly 2 and Golfech 1 sites now not set to come back online until June.
EDF estimates that French nuclear output for this year will come in at 275-285 terawatt hours, rising to 300-330 terawatt-hours in 2023 and 315-345 terawatt-hours in 2024.
However, that compares to 360.7 terawatt hours in 2021 and annual output ranging from 379-416 terawatt hours between 2013 and 2018.
Last week, Xavier Piechaczyk, head of France’s power grid operator RTE, said France would struggle in coming years to hit that 400 terawatt-hour figure.
He said: “The French nuclear fleet is aging and, in a way, we can be almost certain that it will have difficulty reproducing 400 terawatt-hours per year in the coming years.”
Grid operators in France and the UK have introduced contingency measures to try and avert blackouts if supplies get too stretched.
As well as the problems with nuclear output, cuts in Russian supplies of gas to Europe have raised concerns that power stations which use the fuel might run out.
Clement Bouilloux, an analyst at electricity market monitor EnAppSys, said: “It’s not great news if [France’s nuclear power stations] cannot run at maximum capacity.
“The tensions with gas are far from over and we want to get out of coal.”
Wood Mackenzie estimates France will get back up to 400 terawatt hours in the mid-2020s, but not stay there.
It believes the share of nuclear power in France’s electricity mix will fall in coming decades as more wind and solar farms are built.
Nuclear currently accounts for about 65pc of French electricity but Wood Mackenzie expects this to fall to 20pc in 2050, at the same time as demand for power soars because of electric cars and other moves away from fossil fuels.
Last week EDF also delayed the opening of a new reactor, at Flamanville, by six months, meaning it is not expected to be up and running until the first quarter of 2024.