Wind Turbine Size Classifications

The recent movement for clean, green and alternative energy sources has renewed interested in previously overlooked technologies. One such technology is wind-generated power. This method of electricity generation is accomplished with the use of wind turbines. The three broad classifications of wind turbines, which correspond to size and capability, are the utility class, the industrial class and the residential class.

Utility Class Turbines

• A commercial wind farm gathers power from many individual utility-scale turbines.

  Utility-scale wind turbines are an increasingly common sight as arrays of windmills spring up across the plains of North America. A utility-scale turbine is the type of windmill used in commercial power production. The turbine hub frequently stands at a height of more than 164 feet above the ground, with a rotor diameter of 93 feet or more. Utility-scale turbines typically deliver more than 900 kilowatts of electricity. They are arranged in linked power arrays when used in power plants. Most wind turbine utility power plants today deliver between 20 and 300 megawatts of power.

Industrial Class Turbines

• Industrial-scale turbines provide power for industrial operations and small towns.

  Industrial-scale turbines are typically used in light industrial applications and for village power configurations. These turbines typically range between 80 and 131 feet high at the hub and use a rotor diameter of 50 to 100 feet. They produce between 50 and 250 kilowatts of power each. The power production capabilities of industrial turbines requires access to three-phase power, like commercial utility turbines. As a result, turbines of this size are not usually appropriate for residential use. Industrial-scale turbines are installed by contractors, with the guidance of the manufacturer. They are connected to the grid by the local electrical utility.

Residential Class Turbines

• The scale of the turbine to be used depends on the specific electrical application.

  Residential (small) turbines provide power directly to homes and residential properties. They produce 50 kilowatts or less of electrical power. Typical models have a height between 40 and 100 feet, with rotor diameters of 3.5 to 49 feet. However, even smaller models exist. Turbines producing less than 1 kilowatt of power are frequently used to charge batteries, among other small-scale applications. Large residential turbines can be connected to grid power, depending on the situation.

Turbine Selection

• Selecting the appropriate turbine requires attention to a number of details. The first consideration is the amount of power required. A very small wind turbine is suitable for charging a sailboat battery, but the average North American household uses a great deal of electricity, and so requires a much high hub with a broader rotor diameter. Another key to turbine selection is the average wind speed at various heights on a given property. In high-wind regions, a lower total rotor area is required, whereas it may not be possible to generate useful levels of power in regions with very little airflow.