Integration of North Sea wind energy transpower orders powerful grid connection for two more offshore wind farms (Germany)

Transpower orders its third powerful offshore grid connection. The contract with the consortium of Siemens Energy and Prysmian Powerlink is the starting signal for the third innovative major project of its kind.

The high voltage direct current (HVDC) connection “BorWin2“ with a capacity of 800 Megawatt (MW) will connect the wind farms Global Tech 1 and Veja Mate to the onshore transmission grid.

Together with the additional services separate from the contract with Siemens/Prysmian transpower’s investment for BorWin2 will be in the magnitude of a total of 800 million Euros. “With BorWin2 we make another contribution to Europe’s sustainable energy supply“, said Dr. Christof Schulte, member of the transpower board and responsible for the offshore portfolio. The completion of the grid connection is planned in spring 2013.

Each wind farm is connected with a converter platform in the sea. Here the three phase alternating current produced in the wind farms is converted into direct current and transported 200 kilometres via a high voltage direct current transmission line through the sea and over land to the next point of delivery in the voltage transformation substation on land – in this case in Diele close to Papenburg. Here the direct current is again transformed into three-phase alternating current and fed into the transmission grid.

Diele has already been the connecting substation for the first HVDC offshore connection. The 400 MW-project “BorWin1“ has been completed in 2009 with a 400 million investment. Its 200 kilometre cable makes it the worldwide longest connection for an offshore wind farm with direct current technology. According to the owner of the wind farm the wind energy plans which are supposed to be connected to BorWin1 will be build this year.

Previously transpower built the offshore grid connection for alpha ventus as a single connection in alternating current technology. transpower invested nearly 90 million Euros in the 26 month construction period. The wind farm alpha ventus is in operation already.


Source: transpower, June 11, 2010;