Wind power and the environment

Wind energy, like most of our energy sources, comes from solar energy. Radiation from the sun strikes the Earth, causing regions of unequal heating over land and oceans. This unequal heating produces regions of high and low pressure. The warm air rises and cooler air rushes in to replace it, creating wind.

Wind turbines are used to capture the energy of the wind and convert it into electricity. The scale of use varies from single unit installations, supplying remote locations, to large wind farms comprising many wind turbines. A wind farm of approximately 17 acres is capable of generating one megawatt of electricity.

Wind power is the world’s fastest-growing energy source with growth rates of 30 per cent each year. Wind is used to generate electricity all over the world, notably in the United States, Denmark, Germany, Spain and India. At the end of 2008, the world’s wind generation capacity totalled approximately 120,800 megawatts.

Virtually all regions of Canada have areas with good wind resources. The wind power industry believes it is possible for Canada to produce 50,000 megawatts of wind power, or enough to supply about 20 per cent of the country’s electricity supply. Oceans and large lakes, open prairie and hill or mountain areas often have good winds, and these areas are where Canada’s current wind generation facilities are located.

There are wind farms in Alberta, Saskatchewan, Manitoba, Ontario, Quebec, New Brunswick, Prince Edward Island, Nova Scotia, Newfoundland and Labrador and the Yukon.

In addition to generating electricity, wind is used for providing mechanical power. On the Prairies, for example, there are several thousand wind turbines that pump water.

Wind turbines work like windmills. Wind passing through the blades of the turbines causes the blades to turn rotors that are either connected to electrical generators or mechanical devices such as pumps.

Modern wind turbines use a few very large blades to capture wind energy. The tower height can vary from 60 to 100 metres and the diameter of the blades from 40 to 80 metres.

Wind turbines produce power in wind speeds above about 13 kilometres per hour. In most places where wind turbines are located, winds are above this speed 70 to 80 per cent of the time.