The multi-stage procurement process to deliver a fusion plant, known as STEP – Spherical Tokamak for Energy Production – is led by UK Industrial Fusion Solutions, a subsidiary of the UK Atomic Energy Authority Group.
After months of selection, the bid race is down to three construction consortia and two engineering design teams.
STEP project partner shortlist
Construction partner bidders
Inovus Infrastructure, consisting of Balfour Beatty Civil Engineering as the lead member and Vinci Construction, AtkinsRealis, Mott Macdonald and WSP
ILIOS, consisting of Kier Infrastructure as the lead member and Bam Nuttal, Nuvia, AECOM, Turner and Townsend Infrastructure and Amanda Levete Architects as other members
Ferrovial Mace JV, consisting of Ferrovial Construction UK Ltd as the lead member and Mace Consult as the other member
Engineering partner bidders
Celestial JV: Eni UK as the lead member and AtkinsRealis, Jacobs Clean Energy (now Amentum), Westinghouse and Tokamak Energy
Phoenix (UK) Fusion: Cavendish Nuclear as the lead member, KBR and Assystem Energy and Infrastructure
The shortlisted consortia will now enter detailed discussions with UKIFS, with one successful engineering and one successful construction partner set to be awarded contracts, worth an initial combined value of hundreds of millions of pounds, in late 2025/early 2026.
Fusion is based on the same physical reactions that power the sun and stars, combining two hydrogen atoms to release large amounts of energy.
The construction partner will be tasked with delivering a site development programme, including innovative building designs focused on cost, schedule, safety and sustainability.
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