A corrosion problem on the safety system of French nuclear reactors has spread to at least one other reactor, a new setback that falls badly at a time when the electricity supply is tight and the sector scrutinized as never before.
These problems have pushed the French group EDF to reduce its forecast for nuclear electricity production for 2022 “to 300 – 330 TWh, against 330 – 360 TWh”, because “of the extension of the shutdown period of 5 reactors in the park. French nuclear power plant of EDF, “the group announced in a press release Thursday evening.
Among them, a reactor at the Penly plant (Seine-Maritime) is now also affected by this defect, which had so far only affected more powerful and recent reactors.
“The faults which have been observed on the latest generation reactors have been observed on another reactor”, that of Penly 1, which is already shut down, told AFP Karine Herviou, deputy director general of the Institute for Radiation Protection and Nuclear Safety (IRSN).
The problem had so far only been identified in 1,450 megawatt reactors. The fault detected at Penly 1, a 1,300 MW reactor, is the first to affect another family of reactors.
EDF announced in mid-December the precautionary shutdown of the two reactors at the Chooz (Ardennes) power plant to check for possible faults on its emergency cooling circuit, after the detection of faults in Civaux (Vienne), a another control unit of the same model.
The group has since announced that one of Chooz’s reactors was indeed affected by the same problem. The second is still being investigated.
The problem identified at Penly “would also be due to a phenomenon of stress corrosion, that is to say the same phenomenon which was detected” on the 1,450 MW reactors, said Karine Herviou, referring to “a fault in the ‘order of the millimeter’.
The shutdown of the four Civaux and Chooz reactors in the middle of December deprived France of 10% of its nuclear capacity and caused the already very high electricity prices on the market to jump.
“The performance of checks, the instruction of technical solutions and their deployment lead EDF to extend the shutdown of the reactors of Civaux 1, Civaux 2, Chooz 1, Chooz 2 and Penly 1”, warned Thursday evening the public group of energy.
The RTE network manager has recently increased its level of vigilance on the supply of electricity to France while the availability of the nuclear fleet, also upset by the pandemic, is at its lowest.
– Problems elsewhere? –
France, which derives the vast majority of its electricity from nuclear power, had 10 out of 56 reactors unavailable on Thursday and was deprived of 20% of its capacity, at a time when consumption is high with the drop in temperatures.
The question now is whether other reactors in the French fleet are affected by this corrosion problem.
“We do not know if there are no problems elsewhere. EDF is reviewing all the records” of the controls carried out in the past on the park, indicated Karine Herviou.
“It is impossible to exclude that other reactors of the 1,300 MW series are affected,” said Yves Marignac, nuclear expert from the NégaWatt association.
“This poses a difficult problem for the authorities, which is whether we apply the same logic (as for the 1,450 MW reactors) and preventively shut down the reactors or if we prioritize electrical safety,” he said. added. Because “closing more 1,300 MW reactors would inevitably lead to supply disruptions”.
The new problems revealed on Thursday come at a time when France is questioning its energy future against a background of rising concerns about climate change.
Nuclear power is one of the divisive themes of the presidential campaign, with candidates in favor of this energy (especially the right, the far right but also the PCF) and others hostile (LFI and EELV in particular).
President Emmanuel Macron, who has not yet declared himself a candidate for a second term, announced in November that France would launch a new program to build nuclear reactors.
For the moment, it is only building one of the new generation, the Flamanville EPR (Manche), which has experienced many delays. The last has just been announced on Wednesday: fuel loading has been postponed from the end of 2022 to the second quarter of 2023, for a bill increased by 300 million euros.