Wind energy is actually a converted form of solar energy. The sun's radiation heats different parts of the earth at different rates—most notably during the day and night, but also when different surfaces (for example, water and land) absorb or reflect radiation at different rates. The different radiation levels cause portions of the atmosphere to warm differently. Hot air rises, reducing the atmospheric pressure at the earth's surface, and cooler air is drawn in to replace it. The resulting displacement of air creates wind. Air has mass, and when it is in motion, it contains the energy of that motion. This energy is called "kinetic energy” and a portion of kinetic energy can be converted into mechanical force or power that can be used to perform work.

Wind power is converted to electricity by a wind turbine. In a typical, modern, large-scale wind turbine, the kinetic energy in the wind is converted to rotational motion by the rotor – typically a three-bladed assembly at the front of the wind turbine. The rotor turns a shaft which transfers the motion into the nacelle (the large housing at the top of a wind turbine tower). Inside the nacelle, the slowly rotating shaft enters a gearbox that greatly increases the rotational shaft speed. The output (high-speed) shaft is connected to a generator that converts the rotational movement into electricity at medium voltage (a few hundred volts). The electricity flows down heavy electric cables inside the tower to a transformer, which increases the voltage of the electric power to the distribution voltage (a few thousand volts).

Higher voltage electricity flows more easily through electric lines, generating less heat and fewer power losses. The distribution-voltage power flows through underground lines to a collection point where the power from other turbines may be combined. In many cases, the electricity is sent to nearby farms, residences and towns where it is used. Otherwise, the distribution-voltage power is sent to a substation where the voltage is increased dramatically to transmission-voltage power (a few hundred thousand volts) and sent through very tall transmission lines many miles to distant cities and factories.

Further information about the benefits of wind energy and how it works can be found at the Canadian Wind Energy Association website: www.canwea.ca.