Sizewell C Nuclear Project Gets Final Green Light

The UK government has officially approved the Sizewell C nuclear power station project, marking a new chapter in the long history of the Sizewell nuclear site in Suffolk.

This green light, given on 22 July 2025, sets the stage for a third station at Sizewell alongside its predecessors, Sizewell A and Sizewell B. The Sizewell C nuclear project is now one of the most significant UK nuclear recruitment stories of the decade, following closely behind progress at Hinkley Point C — see our coverage of the recent Hinkley Point C Unit 2 dome lift for how the two programmes compare.

Below we explore the full history of these nuclear power stations from major milestones and staffing through to economic and social impacts.

Sizewell A (1966–2006): Magnox Beginnings and Decommissioning

Sizewell A was the first nuclear station at the site, housing two Magnox gas-cooled reactors.

It operated successfully for 40 years (1966–2006) and is now undergoing decommissioning.

Key milestones in Sizewell A’s history include:

• 1958 – Sizewell site selected for a new nuclear power station by the local council, and plans announced by the CEGB to seek construction consent.
• 1960 – The UK Minister of Power grants approval for Sizewell A to proceed (no public inquiry was deemed necessary).
• 1961 – Construction of Sizewell A begins on 1 April, undertaken by a BNDC consortium (English Electric/Babcock & Wilcox/Taylor Woodrow). Initial budgeted cost was ~£56 million (inflating to £65 million by completion).
• 1965–66 – Reactor commissioning: Unit 1 achieved first criticality in June 1965, and first grid connection on 21 January 1966. Unit 2 followed with first power on 9 April 1966. The station entered full commercial operation by September 1966.
• 1967 – Sizewell A is formally opened on 7 April 1967 by the Earl of Stradbroke, producing ~420 MW and generating ~110 TWh over its lifetime.
• 2006 – Sizewell A ceases generation on 31 December 2006, retiring the Magnox reactors.
• 2009 – Defuelling begins; used fuel removed to storage ponds.
• 2014 – Final spent fuel shipped off-site (Aug 2014), station declared fuel-free by Feb 2015.
• 2025 – Turbine hall demolished, marking major skyline change using innovative explosive techniques.
• Future – Residual structures remain in care-and-maintenance; full clearance projected by ~2077.

Sizewell B (1995–Present): Britain’s Only PWR and Extended Operation

Sizewell B is the UK’s only pressurised water reactor, the second station at Sizewell, featuring a 1,188 MWe PWR unit.

It continues to operate today and is slated for life-extension to 2055.

Key milestones in Sizewell B’s story:

• 1983 – Public inquiry into first UK PWR at Sizewell commences, lasting almost two years.
• 1987 – Plans approved by Secretary of State, paving way for construction.
• 1988 – Main construction begins 18 July; only one of four planned PWRs ultimately built.
• 1995 – First criticality and grid connection in Feb; commercial operation 14 Feb 1995, slightly under £2.03 billion (1987 money).
• 2006 – Post-review, new nuclear build agenda reinstated; Sizewell B remains newest UK reactor until 2010s.
• 2015 – Periodic safety review confirms safe operation for another decade (to 2025).
• 2022 – EDF announces 20-year life extension to operate until 2055, bridging energy gaps.
• 2025 – Nearly 30 years of operation; performance among most efficient in fleet. Life-extension plans progressing.

(Sizewell B currently licensed to 2035, pending life-extension upgrades that may allow 60-year operation, similar to US PWRs.)

Sizewell C (Planned): Twin EPRs and the 2025 Go-Ahead

Sizewell C will feature two French-designed EPR reactors (3.2 GW total), near-replica of Hinkley Point C, with construction starting after the 22 July 2025 Final Investment Decision.

Project milestones:

• 2009 – Sizewell identified as suitable for new nuclear in national policy statement.
• 2010s – EDF develops proposals; joint venture with CGN initially 20% stake; environmental consultations ongoing.
• May 2020 – Site license & Development Consent Order applications submitted; regulatory review begins.
• July 2022 – Development Consent granted by UK Secretary of State.
• Sept 2022 – UK government buys out CGN, invests £679 million (50% share) via RAB model.
• 2023 – Early site works continue; future equity and financing negotiations.
• 22 July 2025 – Final Investment Decision signed; £38 billion project equity: UK government 44.9%, Canada 20%, Centrica 15%, Amber 7.6%, EDF ~12.5%.
• July 2025 – Full construction begins; expected to supply ~6 million homes, target commissioning mid-to-late 2030s.

(Future milestones: first concrete, reactor installation, grid connection, 60+ years operation, final clearance next century.)

Workforce and Staffing Breakdown by Project Phase

Staffing across construction, operation, and decommissioning for all Sizewell stations:

• Sizewell A — Construction (1960s): Several hundred workers, including civil engineers, construction labourers, fitters, welders, and project managers.
• Sizewell A — Operation (1966–2006): More than 300 full-time staff, including reactor operators, maintenance technicians, electrical/mechanical engineers, safety inspectors, and support staff.
• Sizewell A — Decommissioning (2007–present): Around 100 workers in the early phase, reducing to around 50 long-term, including decommissioning engineers, waste management specialists, radiation protection staff, and project supervisors.
• Sizewell B — Construction (1988–1995): Over 10,000 workers in total, with 5,000 at peak, spanning labourers to PhD nuclear physicists, contractors, steelworkers, pipefitters, electricians, and engineers.
• Sizewell B — Operation (1995–present): Around 500 permanent staff plus 200 contractors, including licensed operators, control room technicians, maintenance engineers, safety and environmental specialists, and apprentices.
• Sizewell C — Construction (2025–2030s): Around 10,000 jobs including 1,500 apprentices, spanning civil engineers, heavy equipment operators, welders, electricians, project managers, and reactor installation engineers.
• Sizewell C — Operation (~2030s onward): Around 900 permanent staff, including reactor operators, engineers, chemists, safety and environment officers, security, and admin/support roles.

If you’re exploring a move into any of these roles, our dedicated Sizewell C jobs guide breaks down the 10 highest-demand roles in more detail, and employers can register a vacancy directly with our nuclear team.

Economic and Social Impact: Jobs, Training and Regional Benefits

The Sizewell projects have had a profound economic and social impact on East Suffolk, creating thousands of jobs and workforce initiatives.

Long-Term Employment: Sizewell A & B provided stable, well-paid roles. Sizewell A employed around 300 staff for decades; Sizewell B ~500 permanent, ~£40 million annual payroll. Many leaders began as local apprentices.

Construction Booms: Sizewell B construction (1987–95) peaked at >5,000 workers, many from outside Suffolk, boosting local housing, services, and supply chains. End-of-construction cycles informed planning for the Sizewell C nuclear project.

Sizewell C Job Creation: ~10,000 jobs, 2,600 local East Anglia residents; agreements guarantee 500 jobs each for Ipswich & Lowestoft. Skills hubs, job fairs, and Young Sizewell C programs prepare workforce.

Skills and Training Initiatives: Apprenticeships at Sizewell B (~40–50). Sizewell C programs include post-16 Energy Skills College (2027), technical training, and career pipelines.

Local Supply Chain and Investment: Sizewell C expected £2 billion in Suffolk contracts; >£45 million awarded already. Benefits ripple across manufacturing, logistics, hospitality; funding for infrastructure & community programs.

Overall, Sizewell A–C showcase nuclear energy’s evolving role in UK economy and skills development. With the Sizewell C nuclear project’s 2025 approval now confirmed, East Suffolk remains a nuclear powerhouse for decades — and demand for skilled talent across engineering, construction and operations roles is only set to grow. Browse current nuclear vacancies or get in touch with our nuclear recruitment team to discuss your hiring needs.