The news that the Flamanville nuclear power plant is being subjected to an investigation as a result of a fault in its reactor pressure vessel represents another unwelcome development for the UK’s nuclear power project at Hinkley Point C.

The British facility is also set to use the same European Pressurised Reactor and the same steel has been used for the safety casings for Hinkley Point, which “have already been manufactured.”
What has been described as a “very serious” fault was found in the pressure vessel of the prototype EPR plant in Normandy, France, according to the French regulator, ASN.

A second investigation is now required into the quality of the steel of the pressure vessel or the 50ft-high safety casing at the French facility.

Areva and EDF have proposed to ASN that a new series of tests is conducted on a representative vessel head “in order to precisely identify the location of the zone (in which there was detected a high carbon concentration, leading to lower than expected mechanical toughness) concerned and its mechanical properties.”

The companies said that those new tests are already underway.

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.

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.

A final decision on Hinckley point is expected in June, but the British government and EDF will be hopeful the latest setback won’t deter vital Chinese investment.

The EPR is meant to be one of the safest reactors in the world, and the most energy efficient, but has suffered a number of delays and cost overruns.

The casings were made as long ago as 2007-2008 and though it would be possible to replace them, it would be very expensive and take a long time. Pierre-Franck Chevet, head of the ASN said that a similar Areva forging technique had been used for five other EPRs either planned or being built.

Two of these are in Taishan, China and another two set for Hinkley Point. Components have also been manufactured for one planned for Calvert Cliffs in the US state of Maryland.