daily · Clean Energy

50Hertz installs two offshore substations for 976 MW Gennaker wind farm grid link

50Hertz has completed installation of the OSS Darss and OSS Zingst offshore substations for the 976 MW Gennaker wind farm in the Baltic Sea, a key milestone in the OST-6-1 grid connection project. Allseas' Pioneering Spirit placed the multi-thousand-tonne topsides off the Fischland-Darss-Zingst peninsula, with the 927 MW transmission link scheduled for commissioning in 2028.

By Greener Numbers Editorial Team · Published October 18, 2026 · Updated 10/18/2026

German transmission system operator 50Hertz has completed the installation of two offshore substations for the 976 MW Gennaker wind farm in the Baltic Sea, marking a key milestone in the OST-6-1 grid connection project. The OSS Darss and OSS Zingst platforms were installed on schedule in coastal waters off the Fischland-Darss-Zingst peninsula, within the 12-nautical-mile territorial waters zone, 50Hertz said. The installation used the Pioneering Spirit, the world's largest installation vessel at more than 380 metres long, which positioned the multi-thousand-tonne topsides onto their foundations. The operation involved placing two jacket foundations on the seabed and securing them using suction technology before heavy-lift cranes aboard the vessel lifted the topsides onto the supporting structures. The topsides and jackets were manufactured at shipyards in Vlissingen and Rotterdam/Schiedam in the Netherlands and transported by barge and tugboat across the North Sea into the Baltic. 50Hertz awarded the design, construction, installation and commissioning contract to a joint venture of HSM Offshore Energy, Smulders and Iv-Offshore & Energy, with Allseas Engineering carrying out the offshore installation. The two substations will collect electricity from Gennaker's 63 wind turbines and transform the voltage from 66 kV to 220 kV. Three cable systems will carry the power towards shore and on to the new Gnewitz substation along a route of up to approximately 90 kilometres, comprising up to 53 kilometres offshore and around 35 kilometres onshore. The OST-6-1 connection is designed for a transmission capacity of 927 MW, with commissioning currently scheduled for 2028.

Official source: renews.biz ↗