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In deliveryUnited KingdomWorks£20,000,000,000Add to pipeline

STEP Construction Partner (CP)

Awarded to ILIOS

United Kingdom Atomic Energy Authority(buyer)

Published
Published 22 August 2022
Deadline
Closed 12 July 2024
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Overview

United Kingdom Fusion Energy has awarded a Construction Partner contract to ILIOS valued at £10 billion to help design and build a UK prototype fusion energy plant capable of delivering net energy to the grid, with the contract running until March 2029 and subject to optional extensions up to a maximum 20-year term. The procurement originally included separate Engineering and Construction Partner lots, but the Engineering Partner lot was cancelled, leaving only the Construction Partner role in the final exercise. ILIOS will work alongside the Fusion Partner (United Kingdom Atomic Energy Authority) to develop industrial capabilities for fusion energy delivery.

Contracting authority

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Reveal decision makers

Lots (2)

  • Engineering Partner (EP)

    The Engineering Partner’s (EP) primary responsibility will be to provide the capability to drive the integrated design of the STEP Prototype Plant (SPP), and to then manufacture that plant through a developing supply chain. This includes (but not be limited to) providing capabilities for management of all engineering data, responsibility for the detailed design of SPP systems, equipment, and components, and contracting through the engineering supply chain. The EP will be responsible for leading a supply chain which delivers the manufacture and assembly of the SPP components. See the procurement documents for further details.

    £10,000,000,000

  • Construction Partner

    The Construction Partner’s (CP) primary responsibility will be to collaboratively provide the capability to drive the integrated design of the overall layout, buildings, infrastructure, onsite and offsite facilities of the STEP Prototype Plant (SPP) to fulfil the support, enclosure and environmental requirements of the operational plant. The CP will then purchase, fabricate, deliver and install all elements of the designed facilities utilising existing and new supply chains, directly sourced or contracted resources. The CP’s responsibilities will include (but not be limited to) managing the overall health, safety, environment and security systems applicable to all parties engaged at the site. Additional information: Lot 1 for the Engineering Partner (EP) was cancelled and will not be awarded. Only Lot 2 for the Construction Partner (CP) forms part of this notice.

    £10,000,000,000Won by ILIOS

Key details

Country
United Kingdom
Status
In delivery
Category
Works
Estimated value
£20,000,000,000
Procedure
Selective
Published
22 August 2022
Deadline
Closed
Classification (CPV)
Works for complete or part construction and civil engineering workConstruction work for industrial buildingsLaboratory building construction workEngineering works and construction worksConstruction work for engineering works except bridges, tunnels, shafts and subwaysStructures construction workConstruction works for power plants and heating plantsConstruction work for power plant+31 more

Award outcome

Awarded value
£10,000,000,000
Award date
1 April 2026
Contract period
— → 16 March 2029
Winner
  • ILIOS

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Notice history

Every published notice in this contracting process, newest first.

  1. Contract

    22 April 2026

  2. Tender Update

    12 August 2024

  3. Tender Update

    8 July 2024

  4. Contract Notice

    22 May 2024

  5. Tender Update

    18 April 2023

  6. Prior Information Notice

    10 November 2022

  7. Tender Update

    25 August 2022

  8. Tender Update

    24 August 2022

  9. Prior Information Notice

    22 August 2022

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