He Dreiht: 960 MW Merchant Offshore Wind Without Subsidies — What 15 MW Turbines and a PPA-Driven Model Mean

All 64 Vestas 15 MW wind turbines are now installed at EnBW's 960 MW He Dreiht offshore wind farm in the German North Sea, marking completion of the project's turbine-installation campaign and setting the stage for full commercial operation by late summer 2026. The project — built entirely without state subsidies and expected to generate around 4 TWh of electricity per year, enough for roughly 1.1 million households — is a test case for whether the merchant model can carry offshore wind at utility scale, according to offshoreWIND.biz.

The Project: He Dreiht in Context

He Dreiht sits approximately 85 kilometres northwest of Borkum in Germany's North Sea, in an area leased under Germany's early offshore wind concession framework. The 960 MW facility is currently Germany's largest offshore wind farm — a distinction EnBW's board member for sustainable generation infrastructure underscored when the project fed its first kilowatt-hour into the grid in late November 2025, according to offshoreWIND.biz.

The buildout was deliberately paced by the availability of next-generation installation vessels. The first V236-15.0 MW turbine was installed by Cadeler's jack-up vessel Wind Orca in April 2025; by November 2025, 27 of the 64 turbines were in place and first power flowed. The remaining 37 turbines were installed through early August 2026, with EnBW noting on 6 August that installation would be completed "shortly" before confirming all 64 were on their foundations two days later, per the same report.

Ownership is split between EnBW and a consortium of institutional investors — Allianz Global Investors, AIP Management, and Norway's sovereign wealth fund Norges Bank Investment Management — which holds a 49.9% stake. The structure is significant: infrastructure funds underwriting a market-exposed offshore wind asset signals growing appetite for unsubsidized renewable energy among long-duration capital.

The Turbine: Vestas V236-15.0 MW, the World's Largest Commercially Deployed

He Dreiht is the flagship deployment of the Vestas V236-15.0 MW — the largest wind turbine in commercial operation anywhere, and a turbine class that EnBW has described as a "world first in terms of technology." The parameters, per Vestas' official product specifications and EnBW's commissioning statements:

• Rated power: 15.0 MW
• Rotor diameter: 236 metres
• Swept area: 43,742 m² per revolution (equivalent to roughly six football fields)
• Hub height: 142 metres
• Single-rotation yield: approximately four households' daily electricity consumption, according to EnBW

The upscaling economics are the reason He Dreiht works at 15 MW. Doubling rotor area from the previous 10-12 MW generation roughly triples per-turbine energy yield while the balance of system — foundations, jackets, array cables, and the all-important installation-vessel days — scales sublinearly. The result is lower CAPEX per MW and, critically for a merchant project, fewer turbine-level O&M interventions per unit of energy delivered. For a wind farm projecting ~4 TWh/year, the 15 MW platform cuts the turbine count to 64 where a 10 MW fleet would have required 96 machines.

Subsidy-Free Economics: The PPA-Driven Merchant Model

He Dreiht is the highest-profile test yet of whether a large offshore wind farm can be financed and built without any form of state support. Around EUR 2.4 billion is being invested in the project, which EnBW states explicitly was developed "without state funding" — no feed-in tariff, no Contracts for Difference top-up, no negative bidding compensation, per offshoreWIND.biz.

Instead, the revenue model rests on a portfolio of long-term power purchase agreements (PPAs) signed directly with corporate offtakers — technology companies, industrial manufacturers, an airport, a chemicals group, and public transport operators. This merchant-plus-PPA structure exposes the project to wholesale price risk on its uncontracted balance while de-risking the majority of output at negotiated prices. It is the same shaped-product logic that underpins solar-plus-storage PPAs in markets like Chile and Australia, applied to offshore wind with no storage component.

The PPA Portfolio: 575 MW Across Eight Offtakers

The majority of He Dreiht's output has been contracted through long-term PPAs, and the offtaker mix reads like a cross-section of German industrial and tech demand, per offshoreWIND.biz:

Chemistry group Evonik anchors the portfolio at 150 MW (contracted in two tranches of 100 MW and 50 MW), followed by Deutsche Telekom's power and air-conditioning unit PASM at 100 MW and Google at 100 MW. Frankfurt's airport operator Fraport takes 85 MW, with Bosch and steelmaker Salzgitter Flachstahl each at 50 MW, and 20 MW tranches going to logistics group DHL and rail operator Deutsche Bahn.

Resource and Yield: What 4 TWh Means in the North Sea

He Dreiht's expected annual output — around 4 TWh, sufficient for 1.1 million households — implies a net capacity factor of roughly 48% at the reference wind conditions of the German Bight. That capacity factor is among the highest of any fixed-bottom offshore wind region, driven by North Sea wind speeds that average 9-10 m/s at 100+ m hub heights, with a strong winter peak that aligns with German-electricity demand and wholesale prices.

For an unsubsidized project, the capacity factor is not just a physical figure — it is the single largest lever on revenue per invested euro. Every percentage point of capacity factor on a 960 MW farm is roughly 84 GWh/year of additional merchant-sellable output. At a reference wholesale price of EUR 70/MWh, each point is worth approximately EUR 5.9 million in annual revenue before losses. That is why the turbine upscaling decision mattered as much as the PPA structure.

The wind-solar complementarity is also worth noting in the German Bight context: offshore wind peaks in the winter evening and overnight, partially counterbalancing the summer-dominant solar fleet onshore. As Germany's renewable share climbs, a 4 TWh wind asset feeding the evening winter peak is a structurally different revenue profile than daytime solar — a distinction that matters for any hybrid portfolio analysis.

The Outlier: The Blade Incident and Operational Risk

No commissioning campaign of this scale goes without incident, and He Dreiht had a significant one. In late July 2026, a V236 blade sustained damage, part of which fell into the sea and was recovered by the German Federal Police, as reported on offshoreWIND.biz. EnBW confirmed on 7 August that Vestas is investigating the blade failure while turbine installation continued on the remaining machines.

The incident is a reminder that 115-metre blade manufacturing at the V236's scale is a young process discipline relative to onshore blades, and that blade reliability is a first-order constraint on the O&M budget of a merchant wind farm with no feed-in tariff backstop. A days-long turbine outage at 15 MW of nameplate is a direct, unhedged revenue loss. For a project generating ~EUR 280-300 million of gross annual revenue at current price levels, every day of full-fleet downtime costs on the order of EUR 700,000-800,000 — which is exactly why blade-monitoring and predictive maintenance assumptions belong inside the operating-cost model, not outside it.

Modeling Merchant Offshore Wind in Energy Optima

He Dreiht is a case study in why energy modeling for offshore wind has moved beyond pure resource physics into revenue engineering. A complete analysis needs three layers that simplified tools rarely combine:

• Resource-layer yield. Hub-height wind speed distributions, turbine power curves, wake losses across a 64-machine array, electrical losses, and availability. Energy Optima's wind turbine database includes manufacturer power curves across 111+ turbines, and the platform computes annual energy production with a loss waterfall that separates wake, turbulence, availability, and electrical losses.
• Revenue-layer shaping. A merchant-plus-PPA project has two distinct revenue streams: contracted tranches at fixed PPA prices and the residual volume exposed to a forward wholesale curve. An 8,760-hour dispatch simulation that prices every hour of output against a time-varying price curve — with seasonally and diurnally structured merchant prices — is what distinguishes a meaningful IRR from a static spread-and-multiply estimate.
• Risk-layer exposure. Blade-failure, turbine-availability, and curtailment scenarios change the revenue distribution, not just the point estimate. Energy Optima's 25-year financial projections (NPV, IRR, cashflow) allow a developer to stress the merchant tranche against constricted or compressed wholesale scenarios and see the effect on project IRR immediately.

For developers of comparable N-2 GW-scale subsidy-free offshore projects — EnBW's next German offshore builds, and merchant entries across the North Sea and Baltic — the He Dreiht playbook is the reference template: upscale the turbine, front-load corporate PPAs, price the residual against a modeled forward curve, and size the maintenance reserve for blade-scale events. The same framework applies whether the asset floats, is fixed-bottom, or pairs with storage at the grid connection.

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