Siemens Energy said it has been awarded another order from Minnesota Power for 35 3-megawatt (MW) SWT-3.0-101 direct drive wind turbines for its Bison 2 wind energy center near Center, North Dakota.

The scope of supply for the wind power plant includes the transportation, erection and commissioning of the 35 wind turbines, as well as a three-year service and maintenance agreement.

Deliveries of the wind turbines will commence in August 2012, and the wind power plant is scheduled to be commissioned by the end of 2012.

This order is the third contract award for Siemens direct drive wind turbines in the U.S., including Minnesota Power's Bison 1 North Dakota and Oklahoma Gas & Electric's Crossroads Oklahoma wind power plants, Siemens said.

Our direct drive turbines feature only half the parts required for a conventional geared wind turbine and a significantly smaller number of moving parts, allowing for increased output and improved maintainability, said Jan Kjaersgaard, VP and general manager of Siemens' Americas Wind Power business.

Because of these benefits, there is great interest in this new technology and we are very pleased to deliver this highly innovative and advanced technology to a forward-looking utility like Minnesota Power, Kjaersgaard said.

The Bison 1 and 2 wind energy centers combined have the potential to provide clean electricity to more than 50,000 homes in Minnesota.

The SWT-3.0-101 direct drive wind turbine with a rated power output of 3 MW and a rotor diameter of 101 meters offers an innovative direct drive concept with a permanent magnet generator. The first prototypes of the SWT-3.0-101 have been running for more than a year and are meeting all expectations in terms of reliability and performance.

In addition to the 3-MW direct drive turbine, Siemens launched the SWT-2.3-113 gearless wind turbine with a rating of 2.3 MW and a rotor diameter of 113 meters for low to moderate wind conditions in March 2011. The company also expects to launch a new 6-MW direct drive wind turbine by the end of the year, which will be particularly suitable for large offshore wind power plants.

Wind power is part of Siemens' Environmental Portfolio, which garnered about 28 billion euros in revenues in fiscal 2010.