A consortium led by Japanese industrial giant Mitsubishi will run the grid link to the UK’s 1.2GW Hornsea 1 – the world’s largest operating offshore wind farm – in a deal that values the transmission assets at £1.2bn ($1.7bn).

Diamond Transmission Partners was awarded a 25-year licence by UK regulator Ofgem to own and run the Hornsea 1 link after a competitive bidding round, in return for a guaranteed level of income.

It acquires the transmission assets from the wind farm’s developer Orsted and co-owner Global Infrastructure Partners (GIP). They include the project’s three offshore substations, and a reactive compensation substation that was the first of its kind installed in the world.

Hornsea 1 became the world’s largest wind farm to enter service so far when it was completed in the North Sea in 2019, but will in the next few years be surpassed by sister-project Hornsea 2 at 1.4GW, and by mid-decade the 3.6GW Dogger Bank.

Diamond Transmission Partners, which alongside Mitsubishi includes Japanese power group Chubu Electric Power and HICL Infrastructure Company, has been a regular participant in bidding for UK offshore wind transmission assets under Ofgem’s OFTO regime, under which grid links are auctioned off after being built by wind farm developers themselves.

Last year Diamond scooped the 660MW Walney Extension grid link, and also has Race Bank, Burbo Bank and Galloper on its books.

System under pressure

Ofgem has hailed the mechanism as a huge success, pointing to of £5.7bn of investments in links to 7.8GW of capacity in total, and says it has played a major role in the UK’s world-leading offshore wind build.

However, the entire system of connecting UK projects to land via single point-to-point links is under pressure, with the spiralling number of offshore wind projects planned in UK waters making the onshore work associated with them a planning headache for developers – as seen in a recent legal challenge that froze consent for Vattenfall’s 1.8GW Norfolk Vanguard.

The UK government, which has ambitions to make Britain "the Saudi Arabia of wind power", and Ofgem are looking at alternatives that could see developers share links, reducing the number of connections making landfall, but such a system is unlikely to apply to projects before the end of the decade.

Wind

Mitsubishi bags $1.7bn transmission link to world's largest offshore wind farm