Energy.gov

Wind is a more complex phenomenon than you might think! As the Sun warms the Earth and the planet rotates, it leads to areas of high and low atmospheric pressure that interact with terrain like mountains, oceans, plains and valleys to produce wind. The Energy Department studies wind patterns extensively to identify the best places in the U.S. for wind energy development. | Photo by Warren Gretz, NREL.

The Persians are believed to have pioneered the use of windmills to pump water around 600 B.C. Grinding grain was another early use for the windmill in places like the Middle East, China and ancient Greece -- although there's no evidence that anyone outside of "Don Quixote" ever tried to fight one.

In 1887, James Blyth's revolutionary "wind engine" used cloth sails to generate electricity for his cottage in Marykirk, Scotland, making it the first wind-powered home in the world. Later that same year, Charles Brush completed America's first wind turbine in Cleveland, Ohio, a 60-foot tower design (pictured above) that supplied 12 kW of electricity to his mansion for 20 years. Georges Darrieus is credited with later developing the less-common vertical-axis wind turbine, sometimes called the "eggbeater" shape.

Most modern horizontal-axis wind turbines have three blades. Over decades of testing and experimentation -- much of it conducted at the Energy Department's National Labs -- the three-blade design has become widely accepted as the most efficient design for generating electricity in most cases. | Photo by Dennis Schroeder, NREL.

The nacelle of a wind turbine, where the tower meets the rotor, houses important components like the gear box, which converts the relatively slow rotation of the blades into the higher RPM of the turbine's generator. The yaw drive is a motor that turns the nacelle to keep the rotor facing into the wind at all times. | Energy Department photo.

From large tower segments to complex gearboxes, wind turbines are composed of more than 8,000 separate components. | Photo courtesy of Clipper Windpower.

The average hub height (measured at the center of the blades) of most utility-scale U.S. wind turbines is 491 meters (262.5 feet), about as tall as the Statue of Liberty. According to Energy Department research, next-generation wind turbines with towers 110 to 140 meters (360-460 feet) tall could reach stronger, more efficient winds high above the ground, unlocking access to wind power in all 50 states. | Energy Department photo.

In 2014, Iowa got 28.5% of the electricity it generated in-state from wind, followed by South Dakota at 25.3% and Kansas at 21.7%. Texas leads the U.S. in total wind installed capacity at 14,098 Megawatts, accounting for 9% of its electricity generation. | Photo by Todd Spink, NREL.

The United States ranks second in the world behind China in wind "installed capacity" -- that is, how much total energy its turbines could generate if they were turning constantly. However, America actually generates more electricity from wind than the Chinese -- or any other nation, for that matter! | Photo courtesy of Chris Lim.

Wind energy is now the cheapest form of power, with new power purchase agreements in 2014 averaging a record-low 2.35 cents per kilowatt-hour. That's even cheaper than conventional energy sources like coal, natural gas and nuclear! | Photo courtesy of Jenny Hager Photography.

The U.S. wind power industry added jobs faster than any other sector in 2014, up from 50,500 jobs in 2013. | Photo by Dennis Schroeder, NREL.

"Distributed wind" is the term for a wind turbine (or turbines) providing power directly to a local area (via a microgrid) or site like a home, school, office building or farm, instead of being connected to the main electric grid. Total distributed wind capacity in the U.S. is nearing 1 gigawatt. | Energy Department photo.

The Energy Department's Wind Program funds research nationwide to develop and deploy offshore wind technologies that can capture wind resources off the coasts of the United States and convert that wind into electricity. Offshore wind holds tremendous potential to generate clean, renewable electricity for American homes and businesses, but no offshore wind farms have yet been established in U.S. waters. The Deepwater Wind project (which began construction off Rhode Island in July 2015) would become the first of its kind in the nation, although there are 17 other offshore wind projects in various stages of planning and development along America's shores. | Photo by Senu Sirnivas, NREL.