LirIC Interconnector

Hunterston on the Ayrshire coast and Kilroot on Belfast Lough are the two grid connection points chosen for LirIC. Between them, Transmission Investment plans about 142 km of cable route, with two 320 kV HVDC cables buried underground or under the bed of the Irish Sea and a converter station at each end.

The case for it is capacity. Today the only link across this stretch of water is the Moyle Interconnector, rated at 500 MW and repaired several times since 2001. LirIC would add 700 MW between the Irish Integrated Single Electricity Market and the GB wholesale market, which the developer describes as wider routes to market for traders and large, controllable flexibility for a grid taking on more renewable power.

Transmission Investment, owned by TAQA, is the sole developer. The project has an in-principle award of a cap and floor regime from Ofgem, the arrangement that bounds an interconnector’s revenue, and it was granted a transmission licence in Northern Ireland in 2024. ENTSO-E’s Ten Year Network Development Plan lists it as project 1040. Financial close is targeted for September 2027 and commissioning for 2032.

Because the link lands in two jurisdictions, the cap and floor needs two regulators. Ofgem confirmed its in-principle award on 12 November 2024. Northern Ireland’s Utility Regulator opened its own consultation on 4 December 2025, the first such request for a Northern Ireland interconnector, and A&L Goodbody’s summary scheduled a final determination for December 2026.

Procurement has started as well. Invitations to bid issued in March 2025 put £353 million on the two converter stations, £100 million on their civil works and £245 million on the cables, HVDC World reported.

On the ground the footprint is small. The project’s consultation material describes a converter compound of about 2.5 hectares near Hunterston nuclear power station and about 2.75 hectares beside Kilroot power station, with roughly 0.5 km of land cable in Scotland and about 1 km in Northern Ireland.

Much is still open. The consultation material specifies converter valves built on IGBT semiconductors, which points to voltage source converters, but the length of the subsea section has not been published. No manufacturer has been named. Until financial close, the 2032 date is a target, not a commitment, and you should read it that way. The HVDC explainer covers the two converter types a link like this could use and why IGBT valves belong to the newer of them.