500 tonnes high-voltage transformer station installed in Q7 Windpark
First transformer station located 24 km offshore
4 May 2007
IJmuiden 4 May 2007 - On Thursday 4 May the transformer was installed in Offshore Windpark Q7. This substation had arrived on 1 May in IJmuiden harbour on the Northwest coast of the Netherlands. It weighs over 500 tonnes, measures 10 by 20 metres and is 12.5 metres tall. At arrival in IJmuiden the colossus had been en route for two days from Aalborg in Denmark. This is the first transformer station to be installed at such a distance at sea.
By now all 61 foundations and transition pieces of Q7 windpark have been installed and a start has been made with sea and land cabling. The production and installation of the wind turbines will be completed in September.
From Denmark to Q7
In January 2007 Danish Bladt, a steel contractor specialized in manufacturing large complex steel structures, started building this offshore high-voltage substation. The various components from which the station was built were manufactured in Poland, Spain and Germany. The transformer was shipped to IJmuiden fully tested and ready to use. Shortly after arrival, the official conveyance took place from Bladt to Van Oord, the company that is responsible for installing the substation. Subsequently the station was loaded on to the supply vessel Jumping Jack for transportation to the wind park. The transformer station will be installed on a monopile in the middle of the Q7 wind park, some 24 kilometres off the Dutch coast.
Transforming wind energy
At the substation the voltage is transformed from 22 kV to 150 kV. Otherwise, too much energy would be lost during transportation. A 50-kV export sea cable, that runs 28 kilometres from the station to the shore, will first be connected to the substation, after which eight 22-kV cables will be connected, each of which connect seven or eight wind turbines to the station.