2015-08-03 - DolWin beta left the Norwegian harbor of Haugesund on August 1. It will travel a distance of over 600 kilometers (km) to a destination located 45 kilometers off the German North Sea coast. The platform houses the high-voltage direct current (HVDC) converter and is an integral part of the DolWin2 project, which will connect offshore wind farms in the DolWin cluster with the German transmission grid.
A real giant
Measuring the size of a football field, the 100 meter high structure weighs approximately 23,000 tonnes, making DolWin beta a real giant. The converter platform is being towed by two vessels to its positioning site in the German North Sea over the coming days and then installed using the Gravity Based Structure-concept (GBS-concept).
DolWin beta will be responsible for converting offshore wind power from alternating to direct current, which will then be transmitted through 45 km of subsea and 90 km of underground HVDC cables to be fed into the grid via the onshore converter station located at Heede in northern Germany.
The converter platform has left from the shipyard of ABB’s offshore platform construction partner, Aibel in Norway. The steel structure of the platform was built at Dubai Drydocks and was then transported to Aibel’s yard in Haugesund, where electro-technical equipment like transformers and switchgear as well as other components such as the helideck were installed to prepare DolWin beta to set sail.
DolWin2 – part of the German energy transition
The DolWin2 project was awarded to ABB by the Dutch-German transmission system operator TenneT, to connect offshore wind farms in the DolWin cluster with the German grid. DolWin2 is part of Germany’s ambitious energy transition roadmap, called “Energiewende”, which foresees the generation of more than 6.5 gigawatts (GW) from offshore wind by 2020 and 15 GW by 2030.
ABB has the turnkey responsibility for system engineering, design, supply and installation of the complete offshore wind connection, which is able to feed more than 900 megawatts into the German grid. The project scope includes the offshore converter platform, the sea and land cable systems and the onshore converter station.