A consortium of Diamond Transmission UK (DTUK) and Japan’s Chubu Electric Power has been selected as the preferred bidder to acquire and operate the offshore transmission assets connecting the 1.2 GW Dogger Bank B wind farm to the UK grid.
The transmission system, valued at approximately GBP 1 billion (around EUR 1.2 billion) by the consortium, comprises subsea and onshore cables, an offshore converter station and an onshore converter station.
The consortium will operate the transmission business for 25 years after acquiring the assets and receiving an Offshore Transmission Owner (OFTO) licence from the UK energy regulator, Ofgem. The preferred bidder appointment is part of Ofgem’s Tender Round 11 process.
Ofgem launched the tender round in February 2024 and shortlisted four bidder groups in July that year. Ofgem appointed the consortium of DTUK and Chubu as the preferred bidder on 5 November 2026.
Dogger Bank B, located approximately 130 kilometres off the UK’s east coast, is the second phase of the world’s largest offshore wind farm under construction, the 3.6 GW Dogger Bank Wind Farm, owned by the consortium of SSE Renewables, Equinor, and Vårgrønn. The second phase is currently under construction, with wind turbine installation underway.
The Dogger Bank B transmission system uses high-voltage direct current (HVDC) technology to transmit electricity from the offshore wind farm to the National Grid. Its offshore converter station was installed in April 2024 by Saipem’s Saipem 7000 heavy-lift vessel.
DTUK is wholly owned by Global Infrastructure Partners, part of BlackRock. Following the acquisition, the company will operate eleven UK OFTO projects with a combined capacity of almost 7 GW and a total transferred asset value exceeding GBP 5.5 billion (around EUR 6.6 billion), according to the consortium.
For Chubu, the Dogger Bank B project will be its third UK offshore transmission investment, following its participation alongside DTUK in the Walney Extension and Hornsea 1 OFTO projects. The Japanese utility said it would contribute its technical expertise in transmission systems while building experience in HVDC technology and the operation and maintenance of subsea transmission assets.