By Geert De Clercq
PARIS (Reuters) – French nuclear regulator ASN warned state-controlled utility EDF that it may have to review parts of the design of its new nuclear reactor model if it hopes to get clearance to build it.
EDF’s current “European Pressurised Reactor” (EPR) model – the world’s largest reactor with 1,650 megawatt (MW) capacity – has suffered years of delays and billions of euros of cost overruns at construction sites in France and Finland as its size and many safety features make it unwieldy to construct.
In a bid to make it easier to build, EDF unit Framatome – formerly called Areva – is now designing a new “EPR 2”, which will be cheaper and less complex, most notably because of the single steel-lined concrete hull for its containment building as opposed to the EPR’s double hull.
In initial talks with the ASN, EDF had proposed to design the new EPR 2’s cooling circuit pipes with the same “break preclusion” concept as in the old EPR, of which EDF is building two at Hinkley Point, Britain.
This means that components are manufactured to such a high standard that breakage is ruled out and the manufacturer therefore does not have to make plans for what to do in case of accident.
This break-preclusion concept – which is inherently dangerous according to anti-nuclear organizations – has shown its limits at the EPR under construction in Flamanville, France where badly executed weldings on the main steam lines will lead to new delays and extra costs.
The ASN said in a statement on Thursday that while the overall design of the new EPR 2 seemed to be safe, EDF would have change certain elements for it to be approved, notably the break-preclusion concept for its cooling circuit.