Unfinished Nuclear Plants Raise Safety Doubts

A new generation of giant reactors, meant to provide fresh hope for nuclear power in Europe, has been found to have a serious safety problem.

The future of the world’s biggest nuclear reactor, under construction at Flamanville in northern France, is now in doubt after a serious flaw was found in its steel pressure vessel.

Examination has shown that the steel contains too much carbon, which can weaken the vessel’s structure and breaches safety rules.  The Chinese, who have two similar 1,600 megawatt European Pressurized Reactors under construction, have been warned that they too may share the potentially catastrophic problem.

Investigations are continuing to check whether the problem can be rectified, but whatever happens it will add more delays and greater costs to the already troubled projects.

The problem also casts doubt on the much-heralded nuclear renaissance in Europe, where EPR reactors are being built not only in France but also in Finland.
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Serious blow
It is understood that the maximum allowable carbon content of steel in the pressure vessel is 0.22%, but tests have shown 0.30% in parts of the Flamanville vessel.  This could render it subject to cracking in operation and shorten its intended lifespan.

The discovery is another serious blow to the French nuclear industry, which already faces severe financial problems, partly because of existing delays to the reactors at Flamanville and at Finland's Olkiluoto site.  The Finnish reactor, which is not affected by this problem because its pressure vessel steel comes from Japan, not France, is already nine years behind schedule for other reasons and has more than doubled in cost.

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