Gennaker Offshore Substations Depart for Baltic Sea Installation (Video)

October 9, 2026

The topsides and jackets for two offshore substations serving Germany's 927 MW Gennaker offshore wind farm have departed the Netherlands for installation in the Baltic Sea as part of the OST-6-1 offshore grid connection project.

The OSS Zingst and OSS Darß substations are being delivered by the HSI joint venture, comprising Smulders HSM and Iv, under an engineering, procurement, construction, installation and commissioning (EPCIC) contract.

(Credit: Smulders HSM)
(Credit: Smulders HSM)
(Credit: Smulders HSM)
(Credit: Smulders HSM)

The substations, each with a capacity of approximately 450 MW, will form part of the infrastructure connecting Skyborn Renewables' Gennaker offshore wind farm to transmission system operator 50Hertz's onshore grid.

The topside and jacket for OSS Zingst departed from Schiedam, while the corresponding structures for OSS Darß sailed from Vlissingen.


Their departure follows the completion of engineering, procurement, fabrication, assembly and systems integration activities across the two Dutch yards.

The HSI joint venture is responsible for the full EPCIC scope of both substations, including transportation, offshore installation and commissioning.

“The sail-away of OSS Zingst and OSS Darß is an important milestone for everyone involved. Delivering two complete offshore substations of this scale requires close integration across engineering, procurement, fabrication, systems integration and offshore execution,” said Hans Leerdam, Commercial Director at Smulders HSM.

The OST-6-1 project is being developed to transmit electricity generated by the Gennaker offshore wind farm in the German Baltic Sea to the onshore transmission network.

With both substations now transported from their construction yards, the project is moving into the offshore installation and commissioning phase.

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