Wind energy converts kinetic energy that is present in the wind into more useful forms of energy such as mechanical energy or electricity. Wind energy is a pollution-free, infinitely sustainable form of energy. It doesn’t use fuel; it doesn’t produce greenhouse gasses, and it doesn’t produce toxic or radioactive waste.

Windmills that were used to grind grain are an example of early uses of wind energy. Modern uses of wind energy include generation of electricity and pumping water. Current wind energy machines are called "wind turbine generators", "wind pumps", or more generally, "wind turbines".

The history of wind energy

Humans have used wind energy for thousands of years. Ancient Persians used wind energy to pump water before the birth of Christ. The world was explored by wind-driven ships long before engines were invented. As recently as the 1920s, over a million wind turbines pumped water and provided electricity to farms in North America.

The current interest in wind energy was started by the need to develop clean, sustainable energy systems that can be relied on for the long-term future. Modern aerodynamics and engineering have improved wind turbines. They now provide reliable, cost-effective, pollution-free energy for individual, community, and national applications.

The nature of wind energy

Wind energy is the kinetic energy that is present in moving air. The amount of potential energy depends mainly on wind speed, but is also affected slightly by the density of the air, which is determined by the air temperature, barometric pressure, and altitude. 

For any wind turbine, the power and energy output increases dramatically as the wind speed increases. Therefore, the most cost-effective wind turbines are located in the windiest areas. Wind speed is affected by the local terrain and increases with height above the ground, so wind turbines are usually mounted on tall towers.

The costs of wind energy 

The cost of wind energy is determined by:

• the initial cost of the wind turbine installation 
• the interest rate on the money invested 
• the amount of energy produced 

Any wind turbine that is installed in a very windy area generates less expensive electricity than the same unit installed in a less windy area. So it’s important to assess the wind at the potential site.

Modern wind turbine generators cost between $1500 and $2000 per kilowatt for wind farms that use multiple-unit arrays of large machines. Smaller individual units cost up to $3000 per kilowatt. In good wind areas, the costs of generating electricity range between five and ten cents per kilowatt hour. That cost is somewhat higher than the costs associated with an electrical facility, but wind energy costs are decreasing every year, whereas most conventional generation costs continue to increase. 

In remote areas, generating electricity with diesel generators can range from $0.25 to $1.00 per kilowatt hour. So in good wind areas, electricity that is generated by the wind is clearly cost effective. When compared to the money that is charged by electrical companies, wind energy costs are nearly competitive. And that is without accounting for the environmental and health benefits of using a non-polluting source of energy.

Using wind energy around the world

The use of wind turbine generators is growing around the world. In terms of installation and operation worldwide, the wind power industry now turns over more than 9 billion USD. At the end of 2004, 47,000 megawatts of wind-generated electricity produced some 92 TWh of electricity. That is sufficient energy for the electricity needs of Portugal and Greece combined.

2005 was a record year for new installed capacity in Canada. As of April 2006 Canada’s installed wind energy capacity was 944 MW, enough to power more than 280,000 homes.

Visit an industry directory  for wind energy products. 

Applications of wind energy

The following table shows some applications of wind energy, who uses it and how wind energy is obtained.

The benefits of wind energy

• Wind energy is an ideal renewable energy because:

• Wind energy is quiet and does not present any significant hazard to birds or other wildlife.    
• When large arrays of wind turbines are installed on farmland, only about 2% of the land area is required for the wind turbines. The rest is available for farming, livestock, and other uses.    
• Landowners often receive payment for the use of their land, which enhances their income and increases the value of the land.   
• Ownership of wind turbine generators by individuals and the community allows people to participate directly in the preservation of our environment.   
• Each megawatt-hour of electricity that is generated by wind energy helps to reduce the 0.8 to 0.9 tonnes of greenhouse gas emissions that are produced by coal or diesel fuel generation each year.