Why do wind turbines have (only) three blades?

05. März 2026

The historic windmills found in Western Europe, as can still be admired in northern Germany, the Netherlands or in picture books, for example, usually have four blades. Their traditional counterparts in Majorca have as many as six. But why do modern wind turbines have exactly three rotor blades, neither more nor less?

Sergio Leone’s Western classic “Once Upon a Time in the West” begins with a mournful squeaking noise: the Wild West windmill, which turns endlessly above the run-down railway station somewhere in the middle of nowhere on the prairie, holds up 18 rotor blades to catch the wind. Many of its relatives, which were used for water pumps or, later, for decentralised electricity production, boasted as many as 150.

Modern wind turbines appear sparingly equipped in comparison. Nevertheless, their three rotor blades have long since established themselves as the gold standard, and that with good reason. After all, the towering pillars of the energy transition must meet three requirements: They must produce a lot of electricity, cost as little as possible and run stably. In this context, “stably” means as quietly, safely and low-maintenance as possible.