Sizewell C: MPs question if it will offer value for money

An artist's impression of the planned nuclear plant - Sizewell C - which is expected to cost about £20bn

A parliamentary committee of MPs has expressed concern over the funding model for Sizewell C.

It is planned to build the nuclear plant on the Suffolk coast.

The science and technology committee warned the plan had "significant uncertainties and downsides".

The government, which is investing £870m in the project, said it would provide more detail about its funding plans for nuclear by the end of the year.

Last week, the government announced a further £170m of funding for Sizewell C on top of the £700m already pledged.

Critics have said the MPs' report backed up their claims the project does not make financial sense.

The site for Sizewell C, near existing nuclear buildings on the Suffolk coast

Parliament recently passed the Nuclear Energy (Financing) Act, allowing the government to contribute towards the initial construction costs of a big nuclear project .

It will be funded through a levy on customers' bills and the idea is that it gives the developer certainty to proceed and will encourage private investors to join in.

But critics have attacked the Regulated Asset Base model (RAB) as an "open cheque book" for developers to spend what they like on construction.

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The report from MPs, while accepting that this sort of funding model may be necessary for very big projects, questions whether it represents value for money, noting that "the taxpayer is taking an unknown and uncertain risk of cost overruns".

The government told the committee that RAB would save consumers between £30bn and £80bn but the report said there was "some confusion" over how that figure was reached.

"The choice to proceed with gigawatt-scale nuclear power should not be made without robust estimates of its value for money…… even if it forces a conclusion that, for all its other advantages, gigawatt scale new nuclear is not financeable and that the UK's nuclear ambition would need to be pursued through other nuclear technologies," the report said.

Alison Downes of Stop Sizewell C said the project was "unjustifiable"

Alison Downes, from the campaign group Stop Sizewell C, which has questioned the cost of the project for some time, said: "We support the call for the government to publish Sizewell C's cost and value for money as doing so will expose just how unjustifiable this slow, risky and expensive project is."

The Department for Energy Security and Net Zero said: "Nuclear has a vital role to play in reaching net zero and boosting energy security.

"We have already made it clear that we will publish a nuclear roadmap and consult on alternative routes to market by the end of the year."

Last month, the government's approval of the planned Sizewell C nuclear plant was deemed lawful by the High Court after it was challenged on environmental grounds.

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