Campaign group loses high court challenge over plans to build Sizewell C nuclear plant

A campaign group has lost a High Court bid to challenge a regulator’s decision to issue a licence for a new nuclear power plant.

Theberton and Eastbridge Action Group on Sizewell Limited (TEAGS), which campaigns under the name Stop Sizewell C, claimed the Office for Nuclear Regulation (ONR) unlawfully failed to include sea defences in its considerations when issuing a nuclear site licence (NSL) for the development.

Barristers for TEAGS told a hearing earlier the legal challenge over the decision should be allowed to continue while lawyers for the ONR and Sizewell C Limited (SZC), which owns the site, claimed it should be thrown out.

In a ruling, Mrs Justice Lieven dismissed the claim, ruling that the challenge had “no chance of success” and was “totally without merit”.

She said: “The fundamental argument advanced by the claimant is, in my view, plainly wrong.”

SZC has previously said the 3.2 gigawatt power station project, around 22 miles north east of Ipswich, would support around six million homes.

Ministers said the multibillion-pound project will create 10,000 highly skilled jobs, with its go-ahead being welcomed by unions and the nuclear industry.

In August, the new Labour government established a £5.5 billion subsidy scheme for the site, which the Department for Energy Security and Net Zero said would “provide certainty and ensure the project has access to the necessary financial support to remain on track”.

SZC applied to the ONR for an NSL in June 2020, which was granted in April 2024 and allows preparatory work to begin at the site.

Philip Coppel KC, for TEAGS, said in written submissions the challenge to the issuing of the NSL was “arguable” as the licence does not “cover the event of an accident or other emergency in respect of” sea defences.

In court, he said: “Sea defences have the obvious potential to affect safety.”

He continued: “The regulator cannot treat the consequences of such a mistake as an acceptable risk in the operation of a nuclear reactor.”

Mr Coppel added that “safety trumps all” and that the challenge “is not about stopping the construction of the new plant” but that safety features were “baked into” the NSL’s conditions.

Rose Grogan, for the ONR, said the challenge was “bound to fail” and should be thrown out.

In written submissions, she said: “If at any time the ONR is not satisfied that SZC Ltd has made an adequate safety case for protection against coastal flooding, it has a broad range of powers under the NSL… to prohibit the commencement of operations and to shut them down if they have already commenced.”

Hereward Phillpot KC, for SZC, said in his written submissions: “There is no requirement in law or guidance for the coastal defences to be within the site boundary.”

He continued: “Safety, including in respect of coastal flood risk, was subject to detailed and extensive assessment… the claimant does not and could not make any challenge to that expert assessment.”

The legal challenge comes amid growing opposition to plans to decarbonize the UK's energy system.

Just last week the debate over whether a line of pylons which would stretch 100 miles should be installed through the East of England landed in parliament.

The current plans from National Grid would see electricity lines and 50-metre high pylons begin in Norwich in Norfolk and travel to Tilbury in Essex.

The pylons would transfer electricity from offshore wind farms along the East Anglian coast to the South East of England.

However, people living along the proposed route along with some MPs for those communities have criticised the plans, saying the pylons would "destroy the countryside" and argue there are better alternatives.

Responding to today's hearing, Paul Collins of Stop Sizewell C said "We are disappointed and surprised that the Court concluded that the 1965 Nuclear Installation Act did not require the imposition of a condition, when the Sizewell C nuclear site licence was granted, to deal with a safety issue - namely the sea defences - that was well known at that time. The judge fully acknowledged that the sea defences are critical for the safety of Sizewell C's reactors.

Alison Downes added "It remains the case that we are deeply concerned about this issue. There is still no final design of the sea defences let alone guarantees that the construction is feasible. We thank our legal team and supporters and are considering our position."

Want a quick and expert briefing on the biggest news stories? Listen to our latest podcasts to find out What You Need To Know