Sizewell C: Government's progress on funding criticised
Anti-nuclear power campaigners have criticised the government for not providing more financial information in its announcement about how Sizewell C could be funded.
government said applying a new funding model to the firm behind the plant in Suffolk was "significant".
It said private investors could be attracted by getting a return up front.
Stop Sizewell C said redacted figures meant it was impossible to know if it represented value for money.
Department for Business, Energy and Industrial Strategy (BEIS) has outlined its draft reasons for designating Sizewell C's operating company, NNB Generation Company (SZC) Limited, as able to receive funding through the new Regulated Asset Base (RAB) model.
French energy company EDF and the UK government have said they would take 20% stakes in Sizewell C.
It has been estimated Sizewell C would cost £20bn to construct.
RAB would allow investors to get a return on their money during the build, rather than waiting until electricity was generated, the government said.
government said "over the 60-year lifetime of a generic new large-scale nuclear power station, our funding model could reduce the project cost by more than £30bn".
Energy minister Kwasi Kwarteng said the RAB designation represented "significant progress towards implementing a new funding model which will give nuclear projects the financial support they need and attract private investment".
"Private investors receive greater certainty through a lower and more reliable rate of return in the early stages of a project, lowering the cost of financing it, and ultimately helping reduce consumer electricity bills," he said.
government wants to build eight new nuclear power plants to reduce the UK's dependence on fossil fuels and energy imports.
While local councils and businesses expect Sizewell C to boost the local economy, opponents say nuclear plants are slow to build, expensive, inherently risky and threaten local wildlife.
Alison Downes, from Stop Sizewell C, said: "It's outrageous that ministers are hiding the cost to electricity bill payers and the public purse of Sizewell C, while claiming to be transparent. 
"By redacting the finances, it is impossible to know if the secretary of state's judgement on value for money is sound.
"The government intends to take a special share in Sizewell C, as a means of 'protecting national security interests', yet there is no mention of removing China General Nuclear from the project."
A separate decision on whether to grant government planning approval for Sizewell C is due on 8 July.
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