Free Wind Turbine Output calculator with clear step-by-step results.
Wind power scales with the cube of speed and the square of rotor diameter, which is why site selection dominates turbine choice. The power coefficient cannot exceed the Betz limit of 0.593, and the capacity factor converts an instantaneous rating into realistic annual production.
Power in the wind
P = 0.5 x air density x swept area x wind speed^3
Electrical output
P electrical = P wind x power coefficient x drivetrain efficiency
Small wind installations require planning permission and grid connection approval in most jurisdictions, and output on turbulent low-level sites is frequently far below manufacturer claims. Obtain a site wind assessment before investing.
Because the air has to keep moving to leave the rotor. Betz's law caps extraction at 59.3% of the kinetic energy, and real rotors reach 35-45%.
For a small turbine on an average inland site, yes - often lower. Good onshore wind farms reach 30-40% and modern offshore installations exceed 50%.