Transmission Investment (TI) has officially announced a £700 million package of works for its ambitious LirIC Interconnector project, a subsea electricity link between Northern Ireland and Scotland. The project, designed to strengthen energy ties between the regions, is set to transform the energy market by adding 700MW of capacity between the Irish Integrated Single Energy Market (I-SEM) and Great Britain’s wholesale electricity market.
High-Voltage Interconnector to Link Northern Ireland and Scotland
The LirIC project will see the installation of a 142km high-voltage direct current (HVDC) cable connecting Kilroot in Northern Ireland to Hunterston in Scotland. This crucial link will feature state-of-the-art Voltage Source Converter (VSC) technology, enabling efficient power transmission between the two markets.
To bring this project to life, TI has published procurement notices detailing key contract opportunities. These contracts have been segmented into four distinct lots, covering converter stations, civil works, offshore and onshore HVDC cables, and HVAC connections to the Scottish grid.
Breakdown of Contract Opportunities
Transmission Investment has structured the procurement into four major packages:
- Lot A1: £353M – Converter Stations
Covers design, supply, installation, testing, and commissioning of HVDC converter stations at Hunterston and Kilroot. Contract duration: December 2025 to June 2032. - Lot A2: £100M – Converter Station Civil and Building Works
Includes civil engineering, site preparation, and building construction for the converter stations. Contract duration: December 2025 to December 2032. - Lot B1: £245M – HVDC Cables (Offshore and Onshore)
Covers installation of subsea cables, landing infrastructure, and underground cables. Design, supply, installation, and commissioning are included. Contract duration: December 2025 to June 2032. - Lot B2: £8M – HVAC Cables (Scotland Only)
Involves high-voltage alternating current (HVAC) cables connecting the Hunterston converter station to the Scottish grid. Contract duration: December 2025 to June 2032.
Key Deadlines and Next Steps
Market participants looking to get involved in this major infrastructure project need to act fast. The deadline for requests to participate is set for 24 April, with final contract award decisions expected by 30 November 2025.
The LirIC Interconnector has already secured key regulatory approvals, including an “in principle” cap and floor arrangement from Ofgem in Great Britain and a transmission licence in Northern Ireland. These milestones provide a solid foundation for what promises to be one of the most significant energy projects in the region.
