Make a donation with PayPal, VISA, Mastercard, American Express, Discover cards - it's fast, free and secure!

Home Page

Nonprofit founded in 1988


Alternative energy index

For more information, view the most frequently asked questions about wind power

Wind Power

Humanity has been using the wind to do work for thousands of years. The kinetic energy of the wind can be changed into other forms of energy, either mechanical energy or electrical energy. When wind fills a sail, its kinetic energy is being used to push a sailboat through the water. Farmers have been using wind energy for many years to pump water from wells using windmills like the one shown on the right. Wind is also used to turn large grinding stones to mill or grind wheat or corn, just like a water wheel is turned by water power.

The wind is also used by a wind turbine to make electricity.

According to the on-line Illustrated History of Wind Power Development, the first use of a large windmill to generate electricity was a system built in Cleveland, Ohio, in 1888 by Charles F. Brush. The Brush machine had multiple-blades more than 50 feet in diameter. Over the last 100 years, wind turbines have advanced dramatically through newer technology and better understanding of the dynamics of the wind resource. But in order to generate electricity, you still need relatively constant wind speeds in any given location.

A wind turbine is very similar to a child's pinwheel or the propeller of an airplane. The blade of a turbine is tilted an angle. The movement of the air is channeled creating low and high pressures on the blade that force it to move. The blade is connected to a shaft which in turn is connected to an electrical generator. The mechanical energy of the turning blades is changed into electricity.

Wind speeds typically must be sustained and at least 10 miles per hour to turn larger turbines fast enough to generate electricity. The turbines usually produce about 50 to 300 kilowatts of electricity each. A kilowatt is 1,000 watts (kilo means 1,000). You can light ten 100 watt light bulbs with 1,000 watts. So, a 300 kilowatt (300,000 watts) wind turbine could light up 3,000 light bulbs that use 100 watts.

Wind power for your home
Small wind turbines (usually producing lesss than 10 kilowatts of electricity) can be used to generate electricity for a home or small business. A kilowatt is equal to 1,000 watts -- the amount of electricity that can illuminate ten 100-watt light bulbs.

Local ordinances, zoning and building codes should first be investigated before considering buying a small wind turbine.

The smaller turbines today are fairly efficient, producing electricity in winds as low as 7 to 10 mph. They are also fairly quiet. The wind system usually generates power at the same voltage that your home uses, so the turbine can be wired directly to the home or business' electrical system like an appliance.

When the wind is blowing, the turbine provides power for the home. When it is not blowing, the utility company provides the power. Sometimes both sources provide power for the home. If your home is using less electricity than what the wind turbine is making, your electrical meter may actually "turn backwards." This is called "net metering."

A typical 10 kilowatt home wind turbine system will cost $25,000 - $35,000 to install. Depending on the amount of wind available, it will produce between 10,000 to 18,000 kilowatt/hours (kWh) per year. Such a turbine has a blade diameter of about 20-25 feet and needs to sit on a tower about 100 feet tall. Homes sitting on a one acre parcel could probably accommodate such a turbine, depending on local zoning restrictions.

For information on how to buy a small wind electric system please download the "Buying a Small Wind Electric System: A California Consumer's Guide", (Adobe Acrobat PDF file, 20 pages, 133 kilobytes).

Also visit the American Wind Energy Association's website for information about small wind energy systems -

For more information, view the most frequently asked questions about wind power

Back to alternative energy index

Culture Change mailing address: P.O. Box 3387 , Santa Cruz , California 95063 USA
  Telephone 1-215-243-3144 (and fax)

Culture Change was founded by Sustainable Energy Institute (formerly Fossil Fuels Policy Action), a nonprofit organization.