St. Leon Wind Farm

St. Leon Wind Farm is Manitoba's first wind farm, in St. Leon, Manitoba, Canada. In the first phase 63 wind turbines were erected over a 93km2 area, capable of delivering 99 megawatts (MW). In 2011 a further 10 turbines were purchased, expanding the capacity of the project to 120 megawatts.Wind turbinesEach turbine has three blades made with carbon fiber and balsa wood. Each blade is 41m long. The nacelle containing the gearbox and generator is mounted on a tubular steel 80m 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 4m concrete foundation which extends between 10and 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 12.6and. 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.