Wind turbines' RPM (Rotations Per Minute) speed is the number of complete rotations the blade makes in one minute. The average wind turbine spins at a rate of 15-25 RPM.
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It takes about 4-5 seconds for the wind turbine to make one revolution (but at this time, the wind blade tip speed can reach more than 280 kilometers per hour, which is comparable to high-speed rail), and it can generate about 1. 4 kilowatt-hours of electricity.
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