GB : les régulateurs du nucléaire réservés sur la sécurité de l'EPR

AFP - 1er juillet 2009 - LONDRES - Les quatre réacteurs nucléaires de type EPR que les groupes français Areva et EDF se proposent de construire au Royaume-Uni ont fait l'objet de critiques des autorités locales quant à leur sécurité, dans une lettre révélée mercredi par le Times. Dans une lettre du 16 avril, l'Inspection des Installations Nucléaires (NII) a écrit aux deux groupes au sujet des instruments de contrôle du réacteur, estimant qu'il existait une trop grande interconnectivité entre deux systèmes, supposés être indépendants, l'un faisant fonctionner le réacteur et l'autre assurant sa sécurité.

Le NII décrit dans sa lettre le système comme "exagérément complexe", et fait part de "ses sérieuses inquiétudes sur une proposition qui permet à des systèmes de moindre sécurité de prendre le pas sur des systèmes de sécurité plus élevés". Le Times met en doute la capacité d'EDF, dans ces conditions, à construire dans les délais impartis les quatre réacteurs dont il a actuellement le projet au Royaume-Uni.

La direction de la Santé et de la Sécurité (HSE), qui supervise la NII, a indiqué au journal que le projet d'EPR pourrait être rejeté au Royaume-Uni si les inquiétudes ne pouvaient pas être apaisées de manière satisfaisante. Areva et EDF ont assuré en retour de leur bonne volonté.

EDF indique que la sécurité a toujours été sa principale priorité tandis qu'Areva "assure être déterminée à assurer la sécurité du réacteur EPR et à respecter les demandes spécifiques britanniques". Le groupe se dit "confiant dans la possibilité de trouver une solution dans les mois à venir". L'EPR est actuellement en concurrence notamment avec l'AP1000 de Westinghouse au Royaume-Uni.


Times on Line, 1/7/2009
UK regulator raises French nuclear concerns
Robin Pagnamenta, Energy and Environment Editor

French plans to lead a nuclear power renaissance in Britain have been dealt a major blow after regulators warned of serious reservations about the safety of the reactor technology earmarked for use.

The Nuclear Installations Inspectorate (NII) has written to EDF and Areva, the French companies that want to build four reactors in the UK, to express their concerns about the technology. The letter sets out concerns about the control and instrumentation (C&I) of Areva’s European Pressurised Reactor (EPR).

Described by one nuclear industry source as the “cerebral cortex” of a nuclear power station, C&I governs the computers and systems that monitor and control the station’s performance, including temperature, pressure and power output levels.

The NII, which is conducting a detailed review of two reactor designs for the UK, said the EPR technology was significantly compromised because of the interconnectivity of what were meant to be independent systems designed to operate the plant and ensure its safety.

The Health and Safety Executive, which oversees the NII, said that the EPR design could be rejected for use in Britain if its concerns could not be satisfactorily addressed. “It is our regulatory judgment that the C&I architecture appears overly complex,” the NII letter said. “We have serious concerns about your proposal which allows lower safety class systems to have write access [the ability to override] to higher safety class systems,” it continued.

The letter also highlighted concerns about the absence of safety display systems or manual controls that would allow the reactor to be shut down, either in the station’s control room or at an emergency remote shutdown station.

The NII’s warning will compound the view that EDF, the utility giant that is 85 per cent owned by the French state, is unlikely to meet its target of building its first UK reactor within eight years.

Areva is already scrambling to produce revised plans but the design assessment phase could be delayed well past its expected completion in 2011.

EDF wants to build four reactors in Britain at two sites, Hinkley Point in Somerset and Sizewell in Suffolk. Last year it spent more than £12 billion acquiring British Energy, the UK nuclear generator, to secure access to them.

The French-designed EPR is the world’s most powerful nuclear reactor. Each is capable of generating 1,600 megawatts of electricity — enough to supply a city of nearly 2 million people.

While two EPRs are being built in Finland and France, none is yet in service. The prototype EPR, at Olkiluoto in western Finland, is running three years late and billions of euros over budget.

The NII said that it would grant a licence for the EPR reactor only if it was satisfied that the reactor design could be built and operated safely and securely.

Finnish regulators raised earlier concerns about the reactor’s C&I systems but this is the first time that their British counterparts have done so.

Areva and EDF are in talks with the NII about a revised design. Areva said: “The group is committed to ensuring the safety of the EPR reactor and to meeting the UK’s specific requirements. The group is confident that a solution can be defined in the months to come.”

EDF said safety was the company’s No 1 priority at all times.

 


Observatoire du nucléaire