The Hinkley Point project in southwest England, which aims to provide seven percent of Britain's total power needs, has been dogged by spiralling costs since the government signed up for it in 2016.

The latest increase is equivalent to $687 million.

"The start of electricity generation from Unit 1 is now expected in June 2026, compared to end-2025," EDF said a statement Wednesday.

"The project completion costs are now estimated in the range of 22 to 23 billion pounds", it added, up around pound500 million (565 million euros) from figures given in September 2019.

EDF said its announcements followed "a detailed review... to estimate the impact of the (coronavirus) pandemic so far".

The British government, hit by soaring debt to deal with the coronavirus pandemic, insisted that taxpayers would not be affected by the revised cost of Hinkley.

"The government negotiated a competitive deal on Hinkley Point C, the first new nuclear power station in a generation, ensuring consumers won't pay a penny until the station generates electricity," said a statement from Britain's energy department.

"Any increase in costs will be borne entirely by EDF and their investment partners and not by consumers or taxpayers," it added.

Britain in 2016 signed a deal with EDF and its Chinese partner China General Nuclear Corporation for a project set to cost pound18 billion.

Critics have focused on the proposed design, which uses a new European Pressurised Reactor system that has been beset by huge cost overruns and delays at sites in France and Finland.

Britain's National Audit Office has long criticised the scheme, with the watchdog saying the government has "locked consumers into a risky and expensive project with uncertain strategic and economic benefits".

Doug Parr, chief scientist at Greenpeace UK, said the "folly" of the project had once more been revealed by the EDF update.

"Pushing for a new nuclear programme when renewables prices were plunging will be seen as a mistake of historic proportions by governments of all shades," he said in a statement.

Parr added that the plant threatens to become "a white elephant before it's even working".

But the UK government wants to maintain the 20 percent of electricity it generates from nuclear power to help meet a pledge to reduce carbon emissions to net zero by 2050 and tackle climate change.

Heavily-indebted EDF meanwhile, mainly owned by the French government, is funding around two-thirds of the cost of the project and its Chinese partner the remainder.

Similar problems to those at Hinkley have hit EDF's project at Flamanville in western France, although the firm has successfully launched two reactors with Chinese partners in Taishan, China.

In September, Japan's Hitachi scrapped its multi-billion-pound nuclear plant project in Wales faced with a deteriorating investment environment, in a major blow to Britain's atomic energy programme.

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EDF - ELECTRICITE DE FRANCE

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