Wind Energy

What is it?

  • Wind energy is the conversion of the kinetic energy of wind to a useable form of energy. Often converted into electrical energy, it can also be converted into mechanical energy for example for pumping water, and may also be directly transferred as kinetic energy, for example in the sail of a boat.

How does it work?

  • There are two types of wind turbines, vertical and horizontal axis. They use the same principal of converting the kinetic energy of the wind into rotational energy that drives a turbine. There can be some variation in design, however the basic principle remains the same. The types commonly seen today are horizontal axis wind turbines. The average efficiency of a modern turbine is 25 to 35%.

Size Considerations

  • Wind turbine sizing can range from a few hundred watts to greater than three megawatts. The physical size can be very small, just large enough to power the electronics on a boat. Larger small scale models can have rotors 3 - 15 meters in diameter. Commercial scale turbines may be over 100 meters tall and have rotor diameters of greater than 40 meters. The technology used differs by the size and type of turbine.
  • Many factors influence the type of turbine to be used. These may include location, local regulations, wind speed, financing, and end use of the power.
  • In Alberta there are differing sets of regulations depending on the power output of a wind turbine.
  • Regulation of micro-generation turbines falls into two categories, < 150 kW and 150kW to < 1 MW.
  • The purpose of having separate regulation is to streamline the process for people who wish to produce environmentally friendly power to connect to the grid and receive credit for the power generated.
  • Turbines of > 1MW are subject to a much more rigorous permitting and approval process.


  • Electricity produced from wind can be characterized in two ways, on-grid, or off-grid.
    • On-grid means the power source is connected to an external electricity or transmission grid.
    • Off-Grid means that the power source is not connected to an external distribution or electricity grid. This may be the case for people who don’t want to be connected to an external grid, or the location does not have access to the grid.

Is it right for you?

  • When considering wind power, some things must be taken into consideration.
    • Available space
    • Safety
    • Financing and expected return
    • Local government regulations
    • Obstructions
    • and wind speed.
  • Other considerations may include the motivation behind wanting to use wind power, understanding wind power and the positive and negative impacts (including impacts to wildlife, noise, aesthetics, electromagnetic interference), and the knowledge to implement and maintain a project.

Positives of Wind Energy

  • Apart from manufacturing and construction, wind energy does not require energy input
  • Apart from manufacturing and construction, wind energy does not produce toxins, or produce greenhouse gasses, including carbon dioxide
  • Lifecycle emission production is significantly less than fossil fuel energy producing technologies
  • Wind is an abundant, constant source of energy in many areas

Issues with Wind Energy

  • Noise from rotating blades
  • Disruption to some wildlife, eg. migratory bats, some species of birds
  • Aesthetics, many commercial wind mills are about as tall as a 40 story building at tip peak height
  • Power production is intermittent
  • A minimum average wind speed of 18 km/hr is required for economic electricity production
  • Impacts to land during construction
  • Installation and maintenance requires skill