Autumn Statement 2022 Reaction

17 November 2022

In response to today’s Autumn Statement, Stop Sizewell C said:

“If the Chancellor is looking for cheap, reliable, energy independence, he is backing the wrong project, as Sizewell C’s ultimate cost and technical reliability are so uncertain and building it is reliant on French state-owned EDF. Green-lighting Sizewell C also loads more tax onto struggling households, who would be forced to pay a nuclear levy on bills for a decade before they could light a single lightbulb. Despite the Chancellor’s statement, Sizewell C still needs financing, and with at least a year before it’s decided whether it will finally go ahead, we’ll keep fighting this huge black hole for taxpayers’ money, when there are cheaper, quicker ways to get to net zero.”



  1. The Autumn Statement says “The government will continue to secure the UK’s energy security through delivering new nuclear power, including Sizewell C (subject to final agreement)…. This will support the government’s commitment to reduce emissions, decarbonise the power system by 2035 (subject to security of supply) and reach net zero by 2050.” It’s assumed the “contracts” the Chancellor referred to, for the £700m Boris Johnson pledged in September, would see the UK government and EDF jointly taking Sizewell C forward in pursuit of a Final Investment Decision. However, that Final Investment Decision could still be 12-18 months away (according to EDF’s 2 November evidence to the Science & Technology Committee (watch at 11.38am). Since Sizewell C is unlikely to be operating by 2035, it can’t help the UK meet its goal to decarbonise electricity generation by 2035, or to reduce CO2 emissions by 68% by 2030 so will need additional invest in projects that can help meet these targets.

  2. Not Cheap: It’s now widely accepted that constructing Sizewell C will cost at least £30bn, yet the ultimate cost is likely to rise further given the number of unresolved issues, including final design for the massive coastal defences required, securing operational potable water supply and addressing the risk to Sizewell B posed by potential turbine disintegration at Sizewell C (para 201), which inside sources say could be problematic and expensive to resolve. Frazer Nash Consulting is reviewing nuclear generation costs and won’t report back until early 2023. Value for Money assessments for Sizewell C must be wide ranging to also include the impact of inflation on the long term future costs of decommissioning and waste management. Rishi Sunak pledged not to leave our children and grandchildren ‘with a debt to settle that we were too weak to pay ourselves’ but by proceeding with risky, expensive Sizewell C his government has done exactly that.

  3. Not Reliable: There are ongoing concerns about the technical reliability of the EPR reactor with Taishan I being offline for 12 months after fuel failure early in its operational life. French and UK regulators are aware of vibrations caused by coolant flow distribution at the base of the reactor pressure vessel and may require design modifications. Olkiluoto 3 EPR’s testing programme has now been halted because of cracks in all four feed pumps (cause unknown) and commercial operation delayed yet again. Investing billions in a reactor design that remains unproven is folly, and there is a serious prospect that, unmodified, EPRs may not be safe to operate at full capacity. While in the UK, EDF is pushing to build more EPRs to get the “fleet effect”, in France EDF has acknowledged the problems with the EPR and is applying its learnings into the simpler EPR2 design, of which Macron has said he wants six built.

  4. Nuclear Tax. Unlike Hinkley Point C, wholly paid for by the companies who will profit from its electricity, Sizewell C’s only chance of securing private finance is a RAB model, meaning households would pay a nuclear levy on energy bills. Given that the last Prime Minister suspended green levies, this will send contradictory messages to the electorate.

  5. Alternatives: We support more attention being paid to demand-side action as energy efficiency could quickly save households billions a year and create thousands of jobs. However, multiple credible Future Energy Scenarios (eg by CCC and NGFES) reach net zero without Sizewell C, and a recently published UCL study concluded that a nearly 100% renewable system with no new nuclear (beyond Hinkley C) is least cost design. While carbon footprints are not considered in energy scenario modelling, the carbon emitted in constructing Sizewell C is nearly 4 million tonnes.