The DolWin beta converter platform left Aibel’s yard in Haugesund, Norway on the night of August 1. Following a four-day transport stage, the platform will be installed in the DolWin wind cluster in the German North Sea.
The platform concept is based on experience from the oil and gas sector, and has been developed and adapted to requirements in the offshore wind industry.
“Renewable energy is a focus area for Aibel. DolWin beta is our first wind platform, and thus represents a breakthrough for Aibel,” says CEO of Aibel, Jan Skogseth.
He emphasized that the company has gained valuable experience from the process, which will be useful in future projects.
DolWin beta will be operated by transmission operator TenneT, and will have a capacity of 916 MW of power from three wind parks counting more than 200 turbines. The power is led by cables from the platforms belonging to the offshore wind farms to the converter platform, where it is converted from alternating current to direct current.
This conversion is necessary when the transmission distance between onshore connection point and the wind park exceeds 100 kilometres. The high-voltage direct current is then transported via submarine and underground cables to an onshore converter station, where it is reconverted to alternating current and fed into the German grid.
Aibel’s concept may be used in wind parks with a sea depth between 15 and 45 metres. The actual platform has a deck area of 70 x 100 metres.
Aibel is subcontractor to ABB, which is the general contractor for TenneT, and has designed and built the conversion platform. The actual construction was carried out in Dubai before the platform arrived in Haugesund, Norway, in August 2014.
Aibel provides the platform with all auxiliary systems, while ABB provides the HVDC converter systems and subsystems. When the platform left the yard, all systems had been thoroughly tested.