A giant of the energy transition on the move: the shipping of the Baltic Eagle’s offshore platform already caused quite a stir. With the Ostwind 2 grid connection project, 50Hertz has already laid the foundations at an early stage to ensure that the wind farm will soon be able to feed in plenty of green electricity.
As heavy as around 570 elephants (over 4000 tons!), 50 meters long and more than 30 meters high: the dimensions of the offshore platform of the Baltic Eagle wind farm are impressive. No wonder, then, that even the shipment of this colossus from Belgium to its destination in the German Baltic Sea caused quite a stir. The project is a real European success - and a step further on Europe's path towards climate neutrality. "As a substation at sea, the platform can transform the wind energy generated, so that we can efficiently feed the electricity via our cables into the 50Hertz extra-high voltage grid. Hence the installation is an important milestone for the success of the offshore projects," explains Dr Henrich Quick, Head of Offshore at 50Hertz.
In the future, the electricity generated by 50 wind turbines will be bundled in the offshore platform of the Baltic Eagle wind farm and brought to 220 kV AC voltage. It will be fed into the 50Hertz extra-high voltage grid via the sea and land cables of the Ostwind 2 grid connection project and through the Lubmin substation. The sea and land cables required for this have already been laid over the past two years as part of the Ostwind 2 project.
Cast off: Sail-out from HobokenTechnical masterpiece: Installation of the platform at high seas
Heavy load on the high seas
The offshore platform is five floors high and was built in Belgium. At the end of January 2023, it left the port of Hoboken near Antwerp at dawn on a special transport ship. The transport took more than three weeks, crossing 1740 kilometres to its destination around 30 kilometres northeast of Rügen. There, the so-called heavy lift followed: With the help of a special installation vessel, the platform - the so-called topside - was connected to the metal framework anchored in the seabed - the jacket foundation. A real technical masterpiece!
At the beginning of May, the next technical coup followed with the cable installation. The cables had already been laid on the seabed last year in a safety area next to the transformer platform. The so-called pull-in of the two 220 kV submarine cable systems into the Baltic Eagle platform is a technically very demanding operation. The pull-in took around two and a half days per submarine cable segment. At a water depth of about 40 metres, the submarine cable was pulled into the transformer platform using a winch and another protective tube into the J-tube (the cable support), among other things.
After finishing the installation work for the connection to the 50Hertz transmission grid, some system testing will take place: Afterwards, 50Hertz will be ready for grid connection. The offshore wind farm is scheduled to go into operation at the end of 2024 and will then provide renewable energy for 475,000 households.
What exactly will the grid connection look like? What is the length of the cables at sea and on land? Where are the wind farms located? Answers can be found on our project page Ostwind 2.