50Hertz Places Major Order for 2 GW Offshore Platform in Mecklenburg-Western Pomerania
Berlin/Rostock – Transmission system operator 50Hertz has awarded Neptun Smulders Offshore Renewables (NSORe) of Rostock the contract for the LanWin3 offshore converter platform. The platform, with a transmission capacity of 2 GW, is to be built in Rostock-Warnemünde and in Vlissingen, the Netherlands. It will convert North Sea offshore wind power for transmission via the direct current grid.
Offshore Platforms: Rostock Establishes Itself as a Manufacturing Site for the 2 GW Offshore Segment
For LanWin3, key components of the topside – the main structure of the offshore platform – are to be built at Neptun Werft in Rostock-Warnemünde. Smulders will build the steel substructure, known as the jacket, at its yard in Vlissingen, the Netherlands. NSORe is a joint venture of Neptun Werft, which belongs to the Meyer Werft group, and the Belgian offshore steel construction company Smulders.
With LanWin3, NSORe has received its second major order of this kind from 50Hertz. In June, the transmission system operator awarded NSORe the platform construction contract for LanWin6. The combined order volume for NSORe's share of both offshore converter facilities amounts to around EUR 2.5 billion. According to 50Hertz, a large share of this is to be spent on production and services in Mecklenburg-Western Pomerania.
Building the new 2 GW offshore converter platforms requires specialised fabrication capacity. Besides NSORe, companies active in this market include Seatrium and McDermott. McDermott is building the offshore platforms for Tennet's German 2 GW grid connections BalWin4 and LanWin1 at its fabrication site in Batam, Indonesia. The topsides of these platforms each weigh around 32,000 tonnes, and the jackets around 13,000 tonnes. Seatrium is also building platforms for Tennet's 2 GW programme and, together with GE Vernova, has been awarded, among other contracts, the order for the German 2.2 GW project BalWin5.
Electrical Converter Technology: Siemens Energy Remains Technology Partner for LanWin3
Alongside the offshore platform itself, the electrical converter and high-voltage technology forms the second core segment of the 2 GW system. Siemens Energy continues to supply this technology for LanWin3. In 2024, 50Hertz had originally commissioned Siemens Energy and Dragados Offshore jointly to deliver the converter system, with the offshore platform to be built at a Dragados yard in southern Spain. 50Hertz has now amended the platform part of this contract and awarded it to NSORe. The electrical high-voltage technology remains with Siemens Energy.
The international market for the electrical technology of the new 2 GW systems is likewise served by a few large suppliers. Besides Siemens Energy, GE Vernova and Hitachi Energy supply HVDC converter technology for such offshore grid connections. Hitachi Energy is, among other roles, technology partner for several of Tennet's 2 GW systems and currently also supplies its HVDC technology for the Nederwiek3 and LanWin5 projects.
The division of labour is thus similar across several projects: the electrical converter and high-voltage systems of the technology suppliers are installed on offshore platforms weighing several tens of thousands of tonnes. For LanWin3, both segments come together: NSORe builds the platform, and Siemens Energy supplies the electrical high-voltage technology.
LanWin3 Brings 2 GW of Offshore Wind Power from the North Sea to the Heide Grid Node in Schleswig-Holstein
LanWin3 is to collect the power from an offshore wind farm with a planned capacity of 2,000 MW in the North Sea (site N-11.1) and transport it to the grid node in the Heide area. The wind farm site is located around 120 km northwest of Helgoland. On the offshore converter platform, the alternating current generated is converted into direct current at 525 kV for low-loss transmission over long distances. The power is carried via around 200 km of subsea cable to Büsum and from there via around 15 km of underground cable to the planned multi-terminal hub in the Heide area. According to 50Hertz, LanWin3 is scheduled for completion at the end of 2032.
Image: Offshore grid connection system, offshore wind farm site NOR-11-1, LanWin3, offshore and onshore route © IWR
At the multi-terminal hub, LanWin3 will be connected to the NordOstLink, which carries the direct current on from Schleswig-Holstein towards Mecklenburg-Western Pomerania. There, it is converted back into alternating current and fed into the transmission grid.
For Germany's industrial base, the significance of the new contract lies mainly in platform construction. While large offshore converter platforms for other German 2 GW grid connections are being built in Southeast Asia, among other places, key components for LanWin3 and LanWin6 will in future be built in Rostock-Warnemünde. According to 50Hertz, a large share of the combined NSORe order volume of around EUR 2.5 billion is to flow into production and services in Mecklenburg-Western Pomerania.
Source: IWR Online, 21 Sep 2026
