Heerema Marine Contractors has installed the offshore substation (OSS) topside for the Baltic Eagle offshore wind project, off Germany, using the installation vessel Thialf.
It follows the installation of the jacket foundation in October 2022.
The role of the OSS is to collect the electricity generated by the 476MW offshore wind farm’s turbines and transform the supply voltage before feeding it into the onshore power grid at the Lubmin grid interconnection point.
The installation involved the heaviest lifting operation for the Baltic Eagle project with a total estimated net weight of around 4200 tonnes.
Iberdrola has now started the offshore phase to make the OSS ready for energisation.
This will be followed by the installation of the monopiles to which the wind turbines are attached with transition pieces.
The monopiles have been manufactured by the regional company EEW SPC, in Rostock.
Once the wind farm is connected to the grid, the electricity generated by its wind turbines will be delivered via inter-array cables to the offshore substation where it is then transformed from 66kV to 220kV and transmitted via two high-voltage subsea cables across the 90 km distance to the landing point at Lubmin into the 50Hertz transmission grid.
The 220 kV submarine cables were already laid in 2021 and 2022 and deposited on the seabed at a safe distance from the platform position.
The next step will be to move the two cable ends into the transformer platform in the second quarter of this year.
In May 2021, Iberdrola and 50Hertz signed an agreement to cooperate on the construction, installation and commissioning of the OSS for Baltic Eagle offshore wind farm.
Iemants-Fabricom was responsible for the manufacturing of all structural elements of the substation, the marine contractor Heerema for transportation and installation, and Siemens Gas and Power for the delivery of all main electrical equipment for Iberdrola’s low-voltage part of the OSS.
Iris Stempfle, Managing Director of the Offshore Division and Deputy CEO of Iberdrola Deutschland, said: “The offshore substation is a key piece of technology for supplying sustainable energy to hundreds of thousands of households and for the decarbonisation of German industry.”