Small scale wind turbines are simple machines with only a few moving parts. The wind turns the blades which turn the shaft which drives the generator, creating electricity.

Turbine systems generally include:

• Blades (or rotor) which convert the wind's kinetic energy into rotational energy.
• Nacelle (an enclosure) which contains a drive train. This is where the rotational energy is converted to electrical energy.
• Tower to support the blades and nacelle and to place the turbine at an adequate height.
• Electric equipment such as controls, electrical cables, ground support equipment, and interconnection equipment.

The faster the wind speed, the higher the tower and the larger the area covered by the blades, the more electricity generated. A 2.5-kW wind turbine with a 100 foot tower (with rotors four to five meters or 14 feet in diameter) can generate about 3,000 kWh annually at a site with wind speeds averaging 10 miles per hour. This is about enough to meet half the electricity needs of a typical household.