Dogger Bank C substation platform

Ofgem Shortlists Five Bidders for East Anglia Three, Inch Cape and Dogger Bank C Offshore Transmission Assets

Grid Connection

The UK energy regulator Ofgem has unveiled its shortlist of bidders under the Offshore Transmission Owner (OFTO) Tender Round 13, in which five companies and consortia will compete to own and operate the offshore electricity transmission links for the East Anglia Three, Inch Cape and Dogger Bank C offshore wind farms.  

Ofgem said on 24 March that this was the biggest shortlist of bidders since 2019, when five parties were also shortlisted for three OFTO assets, which comprise offshore and onshore systems, including cables, converter stations and substations. The transmission links for the three offshore wind farms in Ofgem’s Round 13 have a combined estimated value of GBP 3.5 billion (approximately EUR 4 billion).

The five bidders which will now be invited to submit their formal tenders are: Diamond Transmission Partners; Equitix; Gravis Sosteneo consortium, formed by Gravis Capital Management and Sosteneo Fund II; John Laing, a consortium formed by Laing Investments Management Services and John Laing Ltd; and Transmission Capital Partners, formed by Public Partnerships Ltd, Transmission Capital Partners Ltd Partnership and Transmission Investment Holdings Limited.

After the competitive tender, Ofgem will select a preferred bidder for each project and then issue transmission licences to the winner(s).

All three offshore wind farms are currently under construction.

Offshore construction on ScottishPower Renewables’ 1.4 GW East Anglia Three started in April 2025, when the first of the project’s 95 monopile foundations was installed. The offshore substation was installed last year, with the wind turbine installation work starting this month.

At the 1.2 GW Dogger Bank C, the third phase of the 3.6 GW Dogger Bank Wind Farm owned by SSE Renewables, Equinor, and Vårgrønn, installation activities are also progressing, with the offshore substation and all foundations in place.

The 1.1 GW Inch Cape offshore wind farm in Scotland, owned by a joint venture between Red Rock Power and ESB, is about to enter the wind turbine foundation installation phase. The project’s offshore substation was also installed last year.

The offshore substations for all three projects were installed by Heerema Marine Contractors’ installation vessel Sleipnir.