Failed EPR nuclear reactors in China and UK.

Nuclear power is under tight surveillance at the moment after a series of incidents in the UK and China.

In the United Kingdom, two power stations are causing problems: the Torness power station in Scotland and Heysham 2 in England. These two power plants, whose operation was to end in 2030, are likely to stop before, due to breaches in the reactors. This failing nuclear safety could well compromise the carbon neutrality objectives set for 2050 by the country. Even more worrying, according to Richard Bradfield, technical director at EDF, we can expect similar incidents in other plants in the country. Indeed, breaches could quickly appear in two other older plants in the country, Heysham 1 and Hartlepool, which should normally close in 2024. A week ago, EDF announced that it was going to close its nuclear power plant in Dungeness B, in the south of England, shut down since 2018 due to technical issues. All these incidents raise real questions about the state of health of the English nuclear fleet, even though a new European pressurized nuclear reactor (EPR) project for a power plant under construction at Hinkley was selected. But between rising costs and already expected delays in delivery, its commissioning is not immediately.

England is not the only country struggling with a failing nuclear fleet. We learn that China is also having problems with an EPR reactor installed in the Taishan plant. Besides the United Kingdom, the two Taishan reactors are for the moment the only French-designed EPRs to have entered service in the world. Other units are under construction in Finland and France in Flamanville

On June 3, Framatome, the EDF subsidiary, declared that reactor number 1 at the plant presents "an imminent radioactive risk" . This is the second case of "leakage" on this reactor since 2018. The concentration of rare gases in the primary circuit is worrying on the rise and a radioactive leak has even been detected. Even if EDF wants to be reassuring by declaring that "The presence of certain rare gases in the primary circuit is a known phenomenon, studied and envisaged by the operating procedures of the reactors" , this does not prevent the risk of radioactive pollution. persists. Indeed, as explained to us, Yves Marignac, an expert in nuclear safety: “in normal times, the primary circuit is purged of rare gases. These are then stored in treatment tanks, the time to lose harmfulness. Xenon, for example, sees its radioactivity halved every nine hours. The gases are then released into the atmosphere. “The more a primary circuit is contaminated, the more degassing must be carried out in a just-in-time flow, the shorter the gas decontamination times and the greater the radioactivity released into the atmosphere” . Such a contamination threshold would have led the French authorities to shut down the reactor a long time ago. What appears to be an obvious and essential security measure at this level is not so for the Chinese authorities who do not want to shut down the reactor.

It is still difficult at this stage to determine the causes of all these incidents which we are told are being monitored and under control. The recent history of nuclear power in the world has already shown us that maintaining a certain opacity around nuclear reactors can lead to catastrophes. Of course, the world economies have started again and everything must be running at full speed, but these incidents have an origin that it would be dangerous to minimize. One thing is certain, it is that they will bring a lot of water to the mill of all opponents of nuclear power.