Lessons should be learned from problems with a French reactor that is very similar to one planned in the UK, says Britain’s nuclear safety regulator.
French regulators have been informed of “manufacturing anomalies” in components “particularly important for safety” at Flamanville 3 power plant, in Normandy.
The reactor is similar to one planned for Hinkley Point, in Somerset.
EDF Energy – involved in both projects – said a new series of tests was under way and it was working with regulators.
An investigation revealed potential weaknesses in the steel used to make a safety casing around the reactor at Flamanville, near Cherbourg.
Areva, which is building Flamanville 3 for EDF, says it is the first plant in the “new French reactor fleet”, and it includes Areva’s new EPR reactor.
The UK Office for Nuclear Regulation said it was aware of the French Nuclear Safety Authority’s concerns about the reactor and would continue to liaise with French authorities.
“The UK currently have no EPR reactors but expects that learning from Flamanville 3 will be taken into account in the manufacture of components intended for the planned new reactor at Hinkley Point C,” it said.
By Joe Lynam, BBC business correspondent
These safety issues in France could lead to even further delays in the construction and completion of the proposed £24.5bn Hinkley Point nuclear power plant.
It has already been delayed by months as the government negotiated a contract for EDF to supply electricity at a guaranteed price for 35 years.
The final decision on the project is expected in the coming months but is also delayed by Britain not having a fully functioning government – something which could be exacerbated if talks on forming a government drag on after the election.
These safety concerns in France are not expected to set the Hinkley Point project back too much but they may spook the Chinese companies set to invest in the project.
In a joint statement, Areva and EDF said new tests were under way on the “reactor vessel head and bottom”.
It said this followed initial tests which had shown “greater than average carbon content” – something French regulators said caused “lower than expected mechanical toughness” in the steel.
EDF and Areva added: “Teams are working to perform the additional tests as soon as possible, following approval by the French Nuclear Safety Authority on the test conditions, and to provide the safety authority with all the necessary information to demonstrate the safety and quality of the corresponding equipment.”
The components in question have not yet been fitted at Hinkley, but it would cost money and could delay the project if they had to be entirely re-made.