Is Sizewell C actually going to be built?

Boris Johnson has said negotiations could be finalised in the coming weeks.

It was going to be the last major transgression of Boris Johnson’s premiership. The Prime Minister had been widely expected this week to sign off on plans for the government to take a stake in the controversial development of Sizewell C, a new nuclear power plant on the Suffolk coastline. The pledge would have broken with the convention that outgoing prime ministers avoid making new funding commitments but Johnson, true to form, appeared ready to press on.

Yet when the opportunity came, the Prime Minister took a different approach. Rather than revealing that the state was prepared to acquire 20 per cent of the development, which is predicted to cost more than £20bn, Johnson committed £700m to its construction from an existing funding pot. The next government will have to commit significantly more – as much as £6bn – if it is to secure a deal with the French energy giant EDF and other investors to kickstart the build.

Nevertheless, Johnson struck an optimistic tone in his speech on Thursday (1 September). “In the course of the next few weeks I am absolutely confident that it will get over the line,” he said at Sizewell. “Let’s think about the future. Let’s think about our kids and our grandchildren, about the next generation. So I say to you, with the prophetic candour and clarity of one who is about to hand over the torch of office, I say go nuclear and go large and go with Sizewell C.”

Nuclear power plants are fraught with financial risk, subject to spiralling costs and typically do not begin to deliver a return for several years after they are finished. Some experts have estimated that Sizewell C will take a decade and a half to build. EDF, the only viable developer, therefore expects the government to step in to de-risk the project. Ministers are promising not only to invest taxpayer money up front, but also levy an extra fee on consumers’ energy bills to ensure EDF starts earning a return on its investment before the power station comes online.

This has led to a major row over how much consumers will be expected to contribute towards the project. The government has said the surcharge will peak at £1 a month for a typical household, but campaigners contend that this is based on the most optimistic scenario and that payments could be three times higher. John Armitt, chair of the National Infrastructure Commission (NIC), told the Financial Times in May that the government needed to “come clean” with the public over the impact of new nuclear developments on energy bills.

However, the Commission says it is in favour of some nuclear developments, such as Sizewell C, to support the transition to more renewable energy. In light of the war in Ukraine, the desire for “lessening our dependency on external sources of [energy]” will “increase the argument for nuclear, whether it’s projects like Sizewell” or the discussions around smaller nuclear reactors, Armitt told me. The next government, he adds, “will want to at least keep the nuclear programme moving over the coming years”. Ministers have already pledged to triple how much energy the UK produces from nuclear sources by 2050.

But while negotiations are far advanced, Sizewell C will remain controversial. Following the disasters of Chernobyl and Fukushima, most nations are reducing, not increasing, their dependence on nuclear energy. Russia’s occupation of the Zaporizhzhia power station in Ukraine has only reinforced concerns about these sites.

There are other practical issues too. “The EDF European pressurised water reactor (EPR) design, currently being built at Hinkley C and planned for Sizewell C, may have a generic fault with its most important safety feature: the reactor pressure vessel,” Paul Dorfman, an associate fellow at the University of Sussex, wrote for Spotlight in May. “As a result, a Chinese EPR has now been shuttered for ten months.” Dorfman, the chair of a group of academics and experts opposed to the development of Sizewell, also warns that sea-level rises threaten coastal nuclear sites.

While the debate over Sizewell and other nuclear power plants will continue to rage, the political momentum behind the project looks likely to survive the change of government next week. But what is harder to predict is when it will be completed, how much it will cost and whether, by the time it is finished, we will still need it.