A wind turbine is installed on top of a tall tower and collects kinetic energy from the wind and converts it to electricity. This electricity is stored in batteries and is then passed through an inverter producing standard electrical power compatible with your home's electrical system. A wind turbine typically lowers your electricity bill by 50 to 90 percent. It is not uncommon for wind turbine owners with total-electric homes to have monthly utility bills of only $8 to $15 for nine months of the year.
However, the economics of a wind system are very sensitive to the average wind speed in the area, and to a lesser extent, the cost of purchasing electricity. As a general rule of thumb, if economics are a concern, a turbine owner should have at least a 10-mph average wind speed and be paying at least 10 cents/kWh for electricity.
Homes use approximately 9,400 kilowatt-hours (kWh) of electricity per year (about 780 kWh per month). Depending upon the average wind speed in the area, a wind turbine rated in the range of 5 to 15 kilowatts would be required to make a significant contribution to meet this demand. A residential wind turbine can be a relatively large device and is not suitable for urban or small-lot suburban homes. Except for very small wind turbines (i.e., with rotors one meter or less in diameter) on very small towers, a property size of one acre or more is desirable.
For most residential systems, the cost of taking wind measurements is not justified. Wind resource data published by the U.S. Department of Energy is sufficient for an experienced evaluator to predict wind turbine performance. In very hilly or mountainous areas, however, it may be best to collect wind data before purchasing a system to ensure that your site is not in a sheltered area. A system designer can help determine if your site is suitable for a wind turbine.
Most small turbines have very few moving parts and do not require any regular maintenance. They are designed for a long life (up to 20 years) and operate completely automatically.