The NetherlandsVattenfall and Siemens Gamesa are developing new 11 MW wind turbines for Hollandse Kust Zuid offshore wind farm.

At the start of the collaboration between Vattenfall and Siemens Gamesa, the Siemens Gamesa Direct Drive 11 MW was selected as the turbine of choice for Hollandse Kust Zuid. At that time, each turbine was planned to feature a 193-meter rotor diameter. A few months ago, the companies decided to upgrade to a rotor diameter of 200 meters.

Kevin Metcalfe from Vattenfall explained why: “The larger blades result in a ~2,100 m2 increase in the swept area, which is about the size of eight tennis courts. This means the turbines generate even more green energy throughout their lifetime, even at lower wind speeds, which is important for a subsidy-free wind farm such as Hollandse Kust Zuid.”

Hollandse Kust Zuid will be the first offshore wind farm to install a new series of wind turbines: the Siemens Gamesa Direct Drive 11 MW. These 140 new turbines will be the biggest ever to be installed at scale.

Turbine prototype testing

Siemens Gamesa is currently testing a prototype of the new 11 MW turbine onshore in Østerild, at a national test center. The prototype has an availability of 95 percent, which means the turbine is only idle 5 percent of the time. The biggest challenge that Siemens Gamesa sees for the coming year is scaling up the production process from a single prototype to serial production of one to two turbines per day. While the towers are almost the same for the 8 MW turbines and production can be scaled up quickly with familiar suppliers, the nacelle contains all kinds of new parts.

Next to that, Siemens Gamesa has already started to produce blades for the Direct Drive 11 MW at a reduced pace, to make sure that production process will also run smoothly when it is scaled up.

Hollandse Kust Zuid

Hollandse Kust Zuid is located 18 kilometres off the coast, in the area between The Hague and Zandvoort.

With its installed capacity of 1,500 MW, the Hollandse Kust Zuid offshore wind farm will be the largest of its kind worldwide, when fully operational in 2023. In 2023, Hollandse Kust Zuid will provide a third of the total installed offshore wind capacity in The Netherlands.