Wind Turbine Lab: The 59 % Limit

A 5 MW wind turbine feathering its blades in a storm inside a wind-tunnel diorama

No wind turbine can capture more than 16/27, about 59.3 %, of the power in the wind passing through its rotor. Slow the air too little and most of it passes unused; stop it entirely and nothing flows through. The optimum leaves the wake at one third of the wind speed (Betz, 1920). A modern 5 MW rotor reaches about 47 %.

This interactive lab needs JavaScript and WebGL.