First offshore cable contract

The announcement by transmission system operator E.ON Netz of a EUR 300 million order placed with ABB for Germany's first offshore wind power cable has given new hope in a country that has been slow off the starting block in utilising its marine wind energy resource (main story). ABB is to supply a 400 MW cable for an offshore wind farm cluster known as Borkum 2, to be built in the German North Sea, 90 kilometres north of the island of Borkum.

The cluster is to consist of three wind farms: Bard Offshore, a 400 MW project of 80, 5 MW turbines from newcomer Bard Engineering, which has said it will soon install a first prototype on land; Hochsee Windpark Nordsee, a second 400 MW project of 80 turbines although no supplier has been named, proposed by EOS Offshore, a joint venture between established wind project developer WPD and small developer Innovent, both based in Bremen; and Nordsee Windpower, a potential 360 MW project of 80 turbines proposed by a company calling itself Global Tech 1.

With the cluster's maximum generating capacity amounting to well over 1000 MW, allocation of the 400 MW transmission capacity will be on a first-come, first-served basis says E.ON Netz' Christian Schneller.

Each wind station will be connected to a power transformer on a platform near the wind turbines. From here the 400 MW cable will follow a 128 kilometre route to shore which will take it across the island of Norderney through a purpose-built underground pipeline. The cable connection is destined to serve the needs of the first wind turbines on site, scheduled for commissioning in 2009. ABB refers to the project as "the most remote wind farm in the world."

Once the cable hits the mainland, it has another 75 kilometres to run on land before feeding into a transformer station at Diele near Papenburg. Each year the cable is expected to operate for the equivalent of around 4000 hours at full load, says E.ON Netz, or less than half the 8760 hours in a year. Even so it will carry enough electricity to meet the annual needs of a city of 400,000 people.

ABB will use its new high-voltage direct-current technology, dubbed HVDC Light. It has already been tested in use, among other places for the 350 MW Finland to Estonia transmission connection that came into operation in December 2006.

Power from a second cluster of four offshore wind stations going under the name Borkum will use a separate connection running along the same route used for Borkum 2. Two further wind station clusters are currently planned for the German North Sea, named Helgoland and Sylt.

Have you registered with us yet?

Register now to enjoy more articles
and free email bulletins.

Sign up now
Already registered?
Sign in