BorWin epsilon offshore converter platform, which will connect to EnBW’s He Dreiht offshore wind farm, arrived at its designated location in the German North Sea several days ago and is now being installed.
The offshore HVDC platform, including the topside and the jacket foundation, left Dragados Offshore’s yard in Puerto Real, Spain, on 18 April.
At the beginning of last week, the 70-metre-tall jacket was lowered onto the previously prepared seabed and anchored with pin piles.
The work was performed using a hydraulic impact hammer deployed from Allseas’ 5,000-tonne crane vessel Pioneering Spirit .
The project team also deployed the Double Big Bubble Curtain (DBBC) system around the platform to reduce underwater noise and protect marine life. Special deterrence systems were also used to keep marine animals away from the construction site, TenneT said in an update on social media on 8 May.
Once fully installed, offshore hook-up, cable connections, and final commissioning and start-up of the platform will be performed before final handover to TenneT, according to Dragados Offshore .
The Spanish company is responsible for the design, supply, construction, transportation, and installation of the platform and the jacket under a contract signed with TenneT in 2020. Siemens Energy is in charge of the design and supply of the HVDC equipment of the platform, as well as the development of the connecting onshore station.
BorWin epsilon will first undergo trial operation and is expected to be commissioned by the end of 2025.
The platform is part of the 900 MW BorWin5 grid connection system that will convert the three-phase current generated by the He Dreiht offshore wind farm into direct current and transport it to the mainland via an approximately 120-kilometre-long subsea cable.
From the landfall in Hilgenriedesiel, the electricity will be transmitted along 110 kilometres of underground cable to the future converter station Garrel/Ost in the Cloppenburg area.
The He Dreiht offshore wind farm, owned by EnBW (50.1 per cent) and a consortium made up of Allianz Capital Partners, AIP and Norges Bank Investment Management (49.9 per cent), is currently in the wind turbine installation phase and is expected to start operation in late 2025.