German Offshore Wind Grid Connections[Draft]

Germany operates a centralised, proactive TSO model for offshore wind grid connections — fundamentally different from the UK’s OFTO competitive tender model. The state plans sites, pre-investigates them, auctions development rights, and the responsible TSO builds the grid connection at its own cost.

Before the WindSeeG entered into force on 1 January 2017, offshore wind projects were permitted under the Seeanlagengesetz (SeeAnlG). Developers applied directly to BSH for individual site permits and arranged grid connections with TenneT. This led to an uncoordinated “first come, first served” process with significant delays and mismatches between wind farm and grid connection readiness.

In August 2025, Germany’s second offshore wind auction of the year attracted zero bids for two centrally pre-investigated North Sea sites (N-10.1, N-10.2, 2.5 GW combined). Root causes included uncapped negative bidding, rising capital costs, supply chain pressures, and declining capture price forecasts.

On 28 January 2026, the federal cabinet approved a drafting aid to suspend all 2026 offshore wind auctions and shift them to 2027. On 30 January 2026, BSH amended the FEP 2025 accordingly. The final auction design for 2027 — including whether Contracts for Difference (CfDs) will be introduced — remains under development.

BSH is the sole competent authority for offshore wind consenting in the German EEZ. The consenting route depends on whether the site was centrally pre-investigated.

BSH publishes the “Standard Investigation of the Impacts of Offshore Wind Turbines on the Marine Environment” (StUK4), prescribing baseline surveys and operational monitoring for benthos, fish, marine mammals (harbour porpoise, seals), resting and migrating birds, and bats.

Published by BSH (first edition 28 June 2019, current: FEP 2025 amended January 2026). The FEP is the master planning document that designates offshore wind sites, specifies which grid connection system serves each site, and sets commissioning timelines synchronised between wind farm and grid connection.

Prepared biennially by the four German TSOs (TenneT, 50Hertz, Amprion, TransnetBW) and confirmed by BNetzA. Since 2017, the previously separate Offshore-Netzentwicklungsplan (O-NEP) has been integrated into the main NEP.

The next generation of German offshore grid connections uses a standardised 2 GW ±525 kV HVDC platform design, replacing the previous ~900 MW±320 kV standard. Benefits include higher capacity per connection (2× improvement), reduced platform count, standardised design enabling serial production, and lower per-MW connection costs.

50Hertz and TenneT are cooperating on an innovative multi-terminal HVDC hub near Heide, Schleswig-Holstein. This connects 4 GW of North Sea offshore wind by 2032 via ~200 km of 525 kV DC underground cable from Heide to Klein Rogahn (near Schwerin) in Mecklenburg-Vorpommern — the first German multi-terminal offshore hub, enabling future meshed grid concepts.

TSOs bear 100% of offshore grid connection costs (converter platforms, export cables to shore, onshore converter stations). These costs are recovered via the offshore grid levy, socialised across all electricity consumers. Wind farm developers bear costs of inter-array cables from turbines to the TSO’s offshore platform.

Germany is a member of the NSEC (established 2016). Members: Belgium, Denmark, France, Germany, Ireland, Luxembourg, the Netherlands, Norway, and the European Commission. Germany hosted the third international North Sea Summit in Hamburg on 26 January 2026.

Germany signed an Offshore Realisation Agreement (November 2022) setting the ambition at 50 GW installed by 2035 — exceeding the WindSeeG statutory minimum of 40 GW.

The NEP 2037/2045 (version 2025, 2nd draft, March 2026) identifies the additional offshore grid connection systems (ONAS) required beyond the Startnetz to reach the statutory target of at least 70 GW by 2045 (§1(2) WindSeeG). For the first time, the TSOs applied offshore optimisation measures developed with the Fraunhofer Institute for Wind Energy Systems (IWES): adjusted area layouts reduce wake effects, raising full-load hours to ~3,900 h/year; mandatory overplanting (20% above ONAS capacity); and investigation of increasing ONAS transmission from 2.0 to 2.2 GW. The result: the same energy yield (238 TWh in Scenario B 2045) can be achieved with 4–7 fewer ONAS than the confirmed NEP 2023 — saving billions in converter, cable, and installation costs that have risen sharply due to supply chain pressures.

No ONAS commissioning is planned for 2035 — the TSOs intentionally schedule a gap year to relieve strained supply chains after the concentrated 2028–2033 build-out. Two ONAS then commission in 2036 to compensate. This draft awaits BNetzA confirmation; the tables below reflect the 2nd draft (Scenario B 2045 as maximum envelope).

No new Baltic Sea connections are planned in the 2037 scenarios. In all 2045 scenarios, an additional 1 GW is assumed in the Mecklenburg-Vorpommern coastal waters, pending completion of the state spatial development plan. Wind farm areas for these systems have not yet been designated.

The first ONDP (published 2024 as part of TYNDP) identified the Northern Seas corridor as requiring approximately 274 GW of offshore wind capacity by 2040. Germany’s 16+ grid connection systems are central to the North Sea and Baltic corridors. Estimated total European offshore transmission CAPEX: ~€400 billion (2025–2050).

Germany hosted the January 2026 Hamburg Summit, which produced a joint target to integrate and network up to 100 GW of generation capacity across borders, mandated Offshore TSO Collaboration (OTC) for 2030–2040 project proposals, and multiple bilateral Declarations of Intent on interconnected offshore grids.

Following the zero-bid outcome for N-10.1 and N-10.2 in August 2025, the federal government suspended all 2026 offshore wind auctions. The final auction design for 2027 is under development. CfDs remain widely expected following Denmark’s similar pivot after its own failed negative-bidding auction, but have not yet been legislated.

Alpha ventus (2027–2028 dismantling) will be Germany’s first offshore wind farm decommissioning. BSH must approve the decommissioning concept. Estimated cost: ~€50 million. BSH published a decommissioning and follow-up use status report in January 2026.

Germany is transitioning from radial connections to multi-terminal hubs (Heide hub, Bornholm Energy Island), with potential for a meshed offshore HVDC grid in the North Sea. Coordination with Dutch, Danish, and Belgian offshore grids via NSEC and BNetzA reform of grid tariff model are advancing in parallel.

This page was fact-checked using automated verification (OpenAI gpt-5.4 with web search). Two iterations were run against the research document, with findings independently verified before corrections were applied.