Press release BoxID: 400866 (TenneT TSO GmbH)
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TenneT orders its seventh grid connection for North Sea wind farms

(PresseBox) (Bayreuth, ) Double record:
- 160 kilometres: longest ever submarine cable for an offshore grid connection
- 864 megawatts: highest ever capacity for a cluster connection

German-Dutch grid operator TenneT is commissioning its seventh offshore grid connection to link North Sea wind farms to the onshore electricity grid. The contract for the 864 megawatt project "SylWin1" has gone to a consortium of Siemens Energy and Prysmian Powerlink. A new substation in Büttel, Schleswig-Holstein, will be built as the onshore grid connection point for SylWin1.
Construction work onshore is to start in early 2012; the grid connection is scheduled for completion by the beginning of 2014.

TenneT is investing a total of almost 1 billion euros in the SylWin1 project and necessary ancillary systems. "Our seventh offshore connection will make a key contribution to the growth of renewable energy and climate protection. However, if we are to bring North Sea electricity to the point of use, approvals for the electricity lines onshore are needed as well as the offshore grid connections", says Martin Fuchs, Chairman of the Management Board. "We need acceptance for the projects and a framework which facilitates faster grid expansion if green energy is supposed to reach the consumer."


The second link in the eastern North Sea will initially connect the DanTysk wind farm to the onshore electricity grid. As the distance between the wind farm and the onshore grid connection point in Büttel is considerable, TenneT is planning a direct current link between the wind farm and the onshore AC grid. The cable route is to run 45 kilometres on land from Büttel substation and a further 160 kilometres undersea to TenneT's offshore platform "SylWin alpha" - the "power source" at sea. Submarine cables will run from the neighbouring wind farm to the converter station on SylWin alpha, where AC current generated by the wind farm will be converted to DC before being transmitted by cable to the new substation in Büttel. The converter station there will then convert the direct current back to alternating current and feed it into the ultra-high voltage grid.

The distribution grid operator TenneT is seeking to take on a leading role on the European market in offshore wind farm connections, and is developing innovative technical solutions in this field.
TenneT has already commissioned seven offshore grid links with a connection capacity totalling over 3000 megawatts for more than 3.5 billion euros. The first two connections for offshore wind farms in the North Sea have already been installed and five more ordered. TenneT will speak to possible investors to win shareholders over their ambitious offshore-projects.

TenneT TSO GmbH

TenneT (now merged with transpower) is Europe's first cross-border grid operator. With approximately 20,000 kilometres of EHV (extra-high voltage) lines, 35 million end users in the Netherlands and Germany, and 1,700 employees, we rank among the top five grid operators in Europe.

Our focus is to develop a north-west European energy market and to integrate renewable energy.

Taking power further