St. Leon Wind Farm
5:34 AM
Posted by Energetic
Each turbine has three blades made with carbon fiber and balsa wood. Each blade is 41 metres long. The nacelle containing the gearbox and generator is mounted on a tubular steel 80 metre tower. The assembly of blades, hub, gearbox, and generator, in total weighs around 220 tonnes. The blades turn at 14 revolutions per minute when the generator is turning at 1200 RPM; the speed increase makes the generator more compact and the overall system more efficient. Each tower has a 4-metre diameter concrete foundation which extends between 10 and 15 metres below grade. The generators produce AC power at around 600 Volts and 60 Hertz. Each tower has a step-up transformer connecting the turbine by an underground cable to the 35 kV overhead wood pole line collection network. The collection network connects the turbines to a step-up transformer station, where the voltage is increase to 230 kV and connection is made to the Manitoba Hydro transmission network. Manitoba Hydro has a 25 year power purchase agreement with Algonquin Power Income Fund, which owns and operates the wind farm.
The Danish-built turbines are designed to operate on wind speeds between 12.6 and 90 kilometres per hour. In very cold weather, -33 C or lower, the units are shut down. About 90% of the year there is sufficient wind to operate the turbines, although not necessarily at full output. In recent years the project has generated at a 35 to 40% annual capacity factor, due to its favorable site.
The array is dispersed over 9000 hectares (23,000 acres) of farmland on the Pembina Escarpment 150 km south-west of Winnipeg, Manitoba, in the rural municipalities of Lorne and Pembina. About five per cent of the area is covered by access roads and foundation sites, leaving the rest available for crops or cattle grazing. Each of the fifty area landowners is paid for the use of the land occupied by a turbine.
The capital cost of the St. Leon Wind Farm project was around CDN $200 million. About $30 million was provided by the federal Wind Power Production Incentive.