Onshore Work Progresses on Ostwind 2 Offshore Wind Grid Connection

50Hertz has reported that new transformers for the onshore substation for the Ostwind 2 offshore grid connection project have been delivered. The substation in Lubmin was first expanded in size and, with the new transformers, its transmission capacity is now being expanded.


Preparatory work for connecting the transformers is currently taking place, including the installation of cooling systems and filling with insulating oil. Afterwards, the first functional tests will be carried out and the transformers should be ready for operation by the end of this year. 

A 320-tonne transformer is placed on the foundation equipped with rails at Lubmin substation site

Once completed, the 750 MW Ostwind 2 grid connection will link the Arcadis Ost 1 and Baltic Eagle offshore wind farms to the German electricity network.

Electricity generated by the two offshore wind farms in the Baltic Sea will be transmitted via three 220 kV subsea cables to the transformer station and then transformed and fed into the 380 kV grid.

The electricity conversion and transmission into the German high-voltage grid takes place at the Lubmin substation, which is also the grid connection point for the two operational offshore wind farms Wikinger and Arkona.

Since the capacities of the existing transformers are not sufficient to convert the additional energy from Ostwind 2, the now delivered additional transformers will make this possible.

50Hertz started installing the subsea cables for Ostwind 2 earlier this year and completed the land cable pull-in for the offshore grid connection last month.

The 257 MW Arcadis Ost 1, developed by the Belgian company Parkwind, is located in the West of Arkona cluster. The wind farm is situated some 20 kilometres off the Rügen island. It will comprise 27 Vestas V174-9.5MW wind turbines slated for commissioning in 2023.

The 476 MW Baltic Eagle, the project of the Spanish energy company Iberdrola, is located in the Arkona Sea cluster. The wind farm is located some 30 kilometres off Rügen, and about 90 kilometres off Lubmin and the onshore substation on the Greifswalder Bodden.