These blades are engineered to capture the maximum amount of wind energy. The aerodynamic efficiency is about. . The rotor blade spins, powered by the flow of wind over its surface, similar to an aircraft's wing creating lift by the air flowing beneath it. Learn more Wind Turbine Explained: Why. . Posted at 1:18 a. Utility-scale turbines, often seen in wind farms, rotate quite slowly, typically operating at a rotational speed between 10 and 20. .