Ofgem to Open Record £3.5 Billion Tender for Hornsea 3 Transmission Assets

Britain’s energy regulator Ofgem is preparing to open its largest-ever competition to find a private owner for the transmission assets linking Ørsted’s 2.9 gigawatt (GW) Hornsea 3 offshore wind farm to the national grid, in a tender round trade press reports could be worth around £3.5 billion ($4.7 billion) — the biggest Offshore Transmission Owner (OFTO) auction Ofgem has run to date.

What’s Being Put Up for Tender

The assets at stake are the infrastructure that carries Hornsea 3’s electricity from the turbines to shore and onto Britain’s grid, rather than the wind farm itself: two offshore converter stations, both installed by September 2026; the offshore export cables, the first of which was laid and pulled ashore earlier in 2026; and onshore cabling together with a converter station in Norfolk that ties the project into the national transmission system. Under Ofgem’s OFTO model, these assets are sold off to independent investors through a competitive tender once construction reaches a defined stage, separating their ownership from the wind farm developer and, in theory, lowering the financing cost of connecting offshore wind to shore.

Confirmed in Regulatory Filings, Reported in Trade Press

Ofgem has published an authority notice under regulation 12(1) of the Tender Regulations confirming that Hornsea 3’s transmission assets have met the requirements to proceed to tender, and that the regulator has received payment and security from the project’s developer as required under regulation 10. That filing establishes the tender is moving forward but does not itself state a launch date or value. Trade publication offshoreWIND.biz reported on October 14 that Ofgem plans to open the round, which it would designate Tender Round 14, on October 21, and put the competition’s value at roughly £3.5 billion — figures that, as of this writing, rest on that trade reporting rather than a public Ofgem valuation.

A Record in a Series of Big OFTO Rounds

If the reported £3.5 billion value holds, Hornsea 3’s transmission assets would be Ofgem’s largest OFTO tender to date, eclipsing earlier rounds by a wide margin. Hornsea 2’s transmission assets sold for a final transfer value of £1.14 billion in an earlier round, while a prior tender covering three separate links — for the Dogger Bank A, Neart na Gaoithe and Moray West wind farms — was valued at around £2 billion combined. Hornsea 3 itself is the larger prize behind the transmission assets: a 2.9 GW wind farm roughly 120 kilometres off the Norfolk coast, built around 197 Siemens Gamesa 14 MW turbines, which Ørsted expects to bring into operation in 2027.

The Third Hornsea Project to Go Through the Process

Hornsea 3 is the third project in Ørsted’s Hornsea zone off the Yorkshire and Norfolk coast to reach this stage, following Hornsea 1 and Hornsea 2, both already operating. Each has gone, or is going, through its own separate OFTO sale once construction reached the qualifying milestones Ofgem’s Tender Regulations require — among them, completed converter stations and an installed export cable — rather than being bundled into a single competition. That project-by-project approach is also why Hornsea 3’s reported £3.5 billion valuation stands out: it reflects the scale of a single 2.9 GW project’s transmission assets alone, not a multi-project package like the one that combined Dogger Bank A, Neart na Gaoithe and Moray West.

Why the OFTO Model Matters for Offshore Wind Financing

Separating transmission ownership from generation is intended to attract a different class of investor — infrastructure and pension funds seeking stable, regulated returns — into offshore wind, rather than requiring developers like Ørsted to carry the full capital cost of both the turbines and the grid connection. Elsewhere in the southern North Sea, that same connection infrastructure is also where much of the remaining construction risk sits, as seen in the engineering work ScottishPower Renewables has been carrying out to land export cables for its East Anglia Two project onshore. For Hornsea 3, a record-sized OFTO tender gives Ofgem a test of investor appetite for offshore transmission assets at a moment when the UK is also weighing the broader cost of its offshore wind build-out against electricity bills.

Sources

• Ofgem, Authority Notice under regulation 12(1) of the Tender Regulations for the Hornsea Project Three OFTO round (TR14), published on ofgem.gov.uk, September 2026 — for official confirmation that the tender process is proceeding and that developer payment/security requirements have been met.
• offshoreWIND.biz, “Ofgem to Launch Record Tender as UK Regulator Seeks Owner of Hornsea 3 Offshore Transmission Assets,” October 14, 2026 — for the reported October 21 launch date, the £3.5 billion value estimate, and Hornsea 3 project specifications.

Illustrative image. Photo: Photo by Kim Hansen. Postprocessing (crop, rotation, color adjustment, dust spot, CC BY-SA 3.0, via Wikimedia Commons — source