Windspire

Mariah Power's Windspire turbine is an example of a vertical axis wind generator. It is 30 feet tall and is capable of producing 2,000 kilowatt-hours per year, according to initial tests (the average U.S. home consumes about 10,000 kilowatt-hours). The company envisions the turbines will be placed on poles at people's homes or in public spaces, such as alongside roads. The company says the sound is imperceptible with 10-mile-per-hour wind.