Wind turbines use blades to collect the wind's kinetic energy. Roughly 1 to 2 percent of the solar energy that reaches Earth gets converted into the movement of air, making wind a form of solar energy one step removed. The sun heats Earth's surface unevenly, creating areas of high and low air pressure, and air flows from high-pressure zones toward low-pressure zones to equalize the difference. Historically, wind power was used by sails, windmills and windpumps, but today it is mostly used to generate electricity. Today, wind power is generated almost. How winds finally end up blowing the way they do results from a fascinating interplay of different forces, each acting on different length and time scales. As of 2024, hundreds of thousands of large turbines, in installations known as wind farms, were generating over 1,136 gigawatts of power, with 117 GW added each year.
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