BorWin1

BorWin1

BorWin1 is the very first grid connection with which TenneT has connected a wind farm to the electricity grid using direct current technology. Up to 400 megawatts (MW) of clean electricity from the BARD Offshore 1 wind farm is transported via a high-voltage direct current (HVDC) transmission line through the North Sea and overland by cable to the onshore grid connection point - the converter station in Diele. From there, it is fed into the German transmission grid and further distributed to consumption-intensive regions. The project name is a reference to the Borkum wind farm cluster located in the western North Sea.

The heart of the grid connection BorWin1 is the offshore converter platform BorWin alpha, which weighs around 5,000 tonnes. With the help of the Thialf floating crane - at over 200 metres long and around 88 metres wide, the largest floating crane in the world at the time - the platform was towed from its production site in Vlissingen in the Netherlands to its destination in the North Sea. There it was subsequently installed and equipped for operation over a period of several months. BorWin1 has been feeding electricity into the German transmission grid since December 2010.

Connecting concept:

The electricity generated at sea is collected in the wind farm's own transformer station. From there the energy is transported to TenneT’s offshore converter platform via a 155 kilovolts three-phase alternating current (AC) cables. The conversion of AC to direct current (DC) takes place in the offshore converter station. The electricity is then transported by submarine and underground cable to the corresponding land station. Here, the electricity is converted back into AC and fed into the TenneT extra-high voltage grid.