Sumitomo’s UK-produced subsea cables to link Kent and Suffolk

July 16th, 2025

The UK National Grid has selected Sumitomo Electric Industries as the preferred bidder to supply and install 138 kilometers of subsea cable for Sea Link, a new high-voltage direct current (HVDC) electricity connection between Kent and Suffolk.

Source: National Grid

Sumitomo Electric will perform the work out of its manufacturing base at the Port of Nigg in Scotland, currently under construction, which will, once operational, mark the first time in around 20 years that HVDC transmission cable has been manufactured in the UK.

The factory will also deliver cable for the Shetland 2 HVDC Link, connecting Shetland and the Scottish mainland.

The preferred bidder announcement follows the recent selection of Siemens Energy to construct the converter stations.

“Delivering projects at this pace and scale demands strong collaboration and early engagement with supply chain partners. The selection of Sumitomo Electric as preferred bidder, and the use of UK-based cable manufacturing for the first time in decades is a major step forward,” said Zac Richardson, Chief Engineer and Offshore Delivery Director for Strategic Infrastructure at National Grid.

“It will bring real investment in UK jobs, skills and industrial capability. Sea Link is part of our wider programme of upgrades that will also support around 55,000 jobs across the UK by the end of the decade.”

The 2 GW Sea Link HVDC transmission project will have converter stations in Suffolk and Kent, linked by a 138-kilometer 52 5kV subsea cable through the North Sea and Thames Estuary.

Construction is expected to begin in 2027, subject to planning consent.

Of note, Sumitomo Electric was one of ten suppliers the National Grid awarded contracts to in March as part of a £59 billion HVDC supply chain framework, setting the stage for the delivery of the required works and equipment for key energy projects across the UK.