Sumitomo confirmed subsea cable supplier for UK electricity connection

December 11, 2025, by Nadja Skopljak

Japanese Sumitomo Electric Industries has officially been contracted to supply and install 140 kilometers of subsea cable for a new high-voltage direct current (HVDC) electricity connection between Kent and Suffolk in the UK, after having the preferred bidder status since July.

The contract secured with National Grid Electricity Transmission (NGET) will see Sumitomo Electric produce the 525 kV HVDC cable for the Sea Link project at its submarine cable factory at Port of Nigg in Scotland.

“The Sea Link Project announcement represents a major step towards investment in the local supply chain in the UK, and we are proud to have its new cable manufacturing facility, which plays a pivotal role in contributing to the UK’s ambitious Net Zero plans, as part of The Great Grid Upgrade,” said Masaki Shirayama, Managing Director of Sumitomo Electric.

“We take this opportunity to thank National Grid for their support of our UK-based operation and, together with Siemens Energy and marine contractor VanOord, strives for successful project delivery.”

Sea Link, on which construction is expected to start in 2027, is one of the key infrastructure projects of NGET’s The Great Grid Upgrade, which aims to substantially increase electricity transmission capacity in the UK.

The 2 GW project will have converter stations in Suffolk and Kent, linked by a 140-kilometer 525 kV subsea cable through the North Sea and Thames Estuary.

“The Great Grid Upgrade is more than an energy programme; it is one of the UK’s biggest engines of economic growth. By investing in skills, securing our supply chain, and working with world-class partners like Sumitomo Electric, we are supporting tens of thousands of high-quality jobs and manufacturing capability the UK needs for the long term,” said Carl Trowell, President of Strategic Infrastructure at National Grid.