UPDATE 1-UK nuclear regulator approves Hitachi-GE reactor design

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LONDON, Dec 14 (Reuters) - Britain's nuclear regulator has approved Hitachi-GE's reactor design, paving the way for it to be used in Horizon's planned new nuclear project in Britain.

The Office for Nuclear Regulation (ONR) said it was satisfied that Hitachi-GE's advanced boiling water reactor (ABWR) meets the necessary safety, security and environmental protection standards for it to be used in plants in Britain.

Hitachi's Horizon Nuclear Power unit plans to construct at least 5.4 gigawatts of new nuclear capacity at two sites in Britain - Wylfa Newydd in Wales and Oldbury-on-Severn in England.

It will use Hitachi-GE's advanced boiling water reactors in the plants.

"The completion of the generic design assessment of the UK ABWR is a significant step in our regulation of the overall process to construct this type of reactor in the UK, ensuring that the generic design meets the highest standards of safety that we expect in this country," said Mark Foy, ONRs chief nuclear inspector.

"Were already working on our assessment of Horizons site license application and on the development of the site specific safety case to progress, in due course, the construction and operation of these reactors at Wylfa Newydd," he added.

The approval paves the way for new nuclear power capacity to be built in Britain, which needs to replace an aging fleet of nuclear reactors and coal plants coming offline in the 2020s.

Separately, South Koreas state utility Korea Electric Power Corp (KEPCO) said last week that it had been picked as a preferred bidder for Toshibas NuGen nuclear project in Britain, throwing the troubled project a lifeline.

KEPCO said in a statement the company planned to negotiate with Toshiba over the next few months to buy a stake in the nuclear project and sign a deal in the first half of next year if the negotiation progresses smoothly. (Reporting by Nina Chestney; Editing by Mark Potter and Adrian Croft)