In May 2020, Heerema Marine Contractors was awarded the contract by Baltic Eagle GmbH, a subsidiary of Iberdrola, to transport and install the offshore substation (OSS) for the Baltic Eagle wind farm in the Baltic Sea. 

Heerema's scope included the installation of a substructure, 8 foundation piles and a 5-deck topside weighing a total of 7,150 metric tons. Once installed, this OSS collects the electricity produced by the 50 9.53-MW wind turbines in the field and to transform the voltage from 66 kV to 220 kV. 

The Baltic Eagle OSS was successfully installed in two phases using Heerema's SSCV Thialf: Phase I was completed in September 2022 and included the transport and installation of the substructure and piles. Six months later, in February 2023, phase II marked the completion of Heerema’s scope with the transport and installation of the topside.  

Crane modifications
This was the first time that one of Heerema's crane vessels was used in the Baltic. In order for Thialf to cross the Storebælt bridge, a number of innovative crane modifications had to be made to the A-frames of the SSCV Thialf. While Thialf was ballasted to the maximum draught of 31.6m, the total air draught with the A-frames lowered was just under 65m. The lifting capacity of the cranes remained unchanged.

About the Baltic Eagle offshore wind farm
The 476 MW Baltic Eagle wind farm is located 30 kilometers northeast of the island of Rügen off the coast of Pomerania, Germany, and currently supplies 300,000 households with renewable energy.