We are primarily tasked with providing power transmission services, system services and facilitating the energy market. Our core tasks follow from our appointment as grid operator under the Dutch 'Elektriciteitswet' (E-wet) and the German 'Energiewirtschaftsgesetz' (EnWG).
First German DC connection to a wind farm at sea
About the project
BorWin1 is the first grid connection with which TenneT has connected a wind farm to the grid using direct current technology. Up to 400 megawatts (MW) of clean electricity from the BARD Offshore 1 wind farm will be transported via a high-voltage direct current transmission line (HVDC) through the North Sea and overland by cable to the landside grid connection point - the converter station in Diele. From there, it is fed into the German transmission grid and distributed to consumption-intensive regions. The project name is based on the Borkum wind farm cluster located in the western North Sea.
The cable connection comprises 125 kilometres of sea and 75 kilometres of land cable. With a total distance of 200 kilometres, BorWin1 was back then the longest connection ever built for the grid connection of an offshore wind farm. Efficient HVDC technology is particularly suitable for long distances and high transmission capacities in order to transport the electricity generated at sea into the grid with as little loss as possible. Both are given in the BorWin1 project.
The heart of the BorWin1 grid connection is the BorWin alpha offshore converter platform weighing around 5,000 tons. With the help of the Thialf floating crane - with a length of over 200 metres and a width of around 88 metres the largest floating crane in the world - the platform was towed from its production site in Vlissingen in the Netherlands to its destination in the North Sea. It was then installed there for several months and equipped for operation. BorWin1 has been feeding electricity into the German transmission grid since December 2010.