Why it matters: The extension would provide 30 years of jobs for Suffolk's nuclear workforce, with apprenticeships continuing throughout the period. It would also reinforce Suffolk's potential to operate three reactors simultaneously by the 2030s, supporting regional ambitions to become the UK's premier nuclear hub.
The details: The investment would be spread over 10-15 years, with work mostly carried out during the power station's planned 18-month outage cycles. However, the extension is conditional on securing a government-backed energy contract (called a Contract for Difference).
The £800m forms part of a wider £1.2bn investment across EDF's UK nuclear fleet between 2026-28. The funding would pay for plant and equipment upgrades to extend operations beyond Sizewell B's current 2035 end-of-life date.
By the numbers: EDF currently employs around 650 people at Sizewell B, supported by around 300 contractors. While staffing has increased slightly to deliver lifetime extension works, the workforce is expected to stabilise at around 600 EDF staff once the upgrades are complete.
Each outage period would see "a temporary influx of several hundred contractors to deliver outage works", an EDF spokesperson said.
For context: Asked about opportunities for local businesses, an EDF spokesperson told Ipswich.co.uk: "There will be some limited contracts for local companies during the work periods."
The spokesperson added that "much of the lifetime extension improvement programme will be delivered by our existing specialist nuclear contractors".
What they're saying: Ashley Shory-Mills, supply chain engagement director at the Suffolk Chamber of Commerce, said: "There is no doubt that Suffolk and the East of England more generally has the potential to become the UK's premier nuclear hub. The benefits of a more aligned nuclear focus in the East, stretches far beyond just electricity generation."
He added: "We have certainly been meeting with the team at Sizewell B to discuss how we can best help them address their ongoing supply chain and skills pipeline needs, including in light of the announcement to extend Sizewell B's operations to 2055."
He said Suffolk needs "the right institutions in place, including a regional nuclear cluster, to support and direct that growth in a coherent manner bringing together businesses, education institutions, planners and policymakers".
A Suffolk County Council spokesperson said: "The proposed extension of Sizewell B's operational life provides long-term certainty around employment at the site and reinforces Suffolk's role in the nuclear and energy sector."
The council said it would work with Sizewell B on workforce planning through to 2055 and ensure local people are aware of opportunities, while monitoring wider impacts on communities.
The bigger picture: The extension would help fill a power shortage as Britain's ageing Advanced Gas-cooled Reactor fleet retires between 2028 and 2030, and with Hinkley Point C facing delays until 2029 or later.
It would also create the potential for three reactors to operate in East Suffolk simultaneously for more than 20 years. Sizewell B currently operates one unit, while the £38 billion Sizewell C project is planned to add two more units, with construction underway and completion expected no earlier than the late 2030s.
Sizewell B, which opened in 1995, is the UK's only pressurised water reactor and supplies around 1.2 gigawatts, or approximately three per cent of UK electricity. In 2025, the plant achieved a 99 per cent load factor (meaning it was generating power almost continuously), generating 10.4 terawatt hours.
What's next: An EDF spokesperson said: "EDF will continue to recruit apprentices for the power station at current levels over the coming years. If the lifetime extension programme is approved then the apprentice programme will also be required to run for a longer period to ensure we have appropriate staffing well into the future."
The company has been engaging with MPs, councils and local business groups over recent years to flag "the upcoming lifetime extension decision and its importance to the future of the power station and the economic activity we support through our operations".
The bottom line: While most specialist work will go to existing nuclear contractors, the extension would secure long-term employment for Suffolk's nuclear workforce and reinforce the county's strategic role in Britain's energy future as it pursues nuclear hub ambitions – subject to a government-backed Contract for Difference being agreed.
