Shetland HVDC Link
Island LinkOperational600 MW320 kV266 km2024
Status:Operational
Capacity:600 MW
Project Company:Scottish Hydro Electric Transmission plc
Type:island link
Expected Life:40 years
Website:www.ssen-transmission.co.uk
Supply Chain (4)
Project Timeline (20)
Aug 2024Commercial Operations Full Power
In August 2024, SSEN Transmission completed final energisation of the 260 km, 600 MW Shetland HVDC Link between the new converter station at Kergord on Shetland and the HVDC switching station at Noss Head in Caithness, connecting Shetland to the GB electricity transmission system for the first time. SSEN confirms that final energisation of the subsea cable was completed in August 2024, and its Gremista Grid Supply Point strategic plan records the Shetland HVDC Link 1 project as completed in August 2024, while an independent fisheries report notes that the HVDC link came online and was operational in late 2024.
Aug 2024Converter Supplier Selected
SSEN Transmission contracted Hitachi Energy to supply the HVDC technology and main circuit apparatus and systems for the Shetland HVDC Link, including the equipment enabling the multi‑terminal operation that connects the new Kergord converter station in Shetland to the Noss Head switching station and into the existing Caithness–Moray HVDC system. Hitachi Energy’s HVDC Light platform and associated grid integration systems form the core of the project’s converter and switching infrastructure.
Aug 2024Substation Supplier Selected
For the Shetland HVDC Link, SSEN Transmission engaged a Siemens & BAM joint venture to construct the associated AC substation and switchgear, complementing BAM Nuttall’s role as main civil engineering contractor for the converter and switching station buildings, access roads and major groundworks. This contract provided the HVAC substation infrastructure required at the onshore connection points to integrate the new HVDC link with the Scottish transmission network.
Aug 2024Onss Commissioned
The Shetland HVDC Link, including the onshore converter station at Kergord in Shetland and the new switching station at Noss Head in Caithness, was commissioned in August 2024, following final energisation of the 260 km subsea cable and completion of associated works, thereby connecting Shetland to the Great British electricity grid for the first time.
Jun 2024First Power
During June 2024, the Shetland HVDC Link transmitted the first flow of electricity from Shetland to the Scottish mainland, marking an initial power transfer on the new 260 km subsea interconnector as part of its commissioning phase. SSEN Transmission’s programme director described this first flow of power from Shetland to the mainland on the Shetland HVDC link as a key moment for the Shetland community, ahead of full energisation later in the summer of 2024.
~Sept 2023Cable Installation Complete
The Shetland HVDC Link’s 260 km HVDC subsea cable system between the Kergord converter station in Shetland and the Noss Head switching station in Caithness was fully installed in three offshore campaigns during 2022 and 2023, with SSEN reporting that the final section of cable was laid on the seabed in autumn 2023, meaning the complete HVDC cable was in place by the end of 2023.
Q2 2023Cable Landfall CompleteStale
Cable landfall works at Weisdale Voe on Shetland, including excavation of a nearshore trench, installation of polyethylene ducts from the onshore transition joint bay to an exit point in around 10 m water depth, and subsequent pull‑in of the bundled HVDC and fibre‑optic cables through these ducts, were scheduled to be completed in Q2 2023.
Q3 2022Cable Landfall CompleteStale
Completion of cable landfall operations at Noss Head in Caithness was planned for Q3 2022, with the subsea HVDC cable to be pulled into the pre‑installed horizontal directional drilled steel ducts from offshore to the onshore transition works and switching station site.
Q2 2022Offshore Site PreparationStale
Further offshore site preparation for the Shetland HVDC Link was planned to commence in Q2 2022, involving pre‑lay grapnel runs and clearance of out‑of‑service subsea cables along the route corridor, with campaigns in Q2 2022 and Q2 2023 expected to take around 20 days in total to remove obstructions ahead of cable laying.
Q2 2022Cable Installation Start
Installation of the bundled pair of 320 kV HVDC submarine cables and the associated fibre‑optic cable for the Shetland HVDC Link was scheduled to start in Q2 2022, to be carried out by NKT’s cable‑laying vessel NKT VICTORIA in three offshore campaigns during 2022–2023; by 11 October 2022 SSEN had notified mariners that HVDC cable had already been laid on part of the route from Caithness to east of Orkney, confirming that offshore cable installation was underway.