Why do windmills typically have 4 blades, yet all modern wind turbines have 3?

Question

Why do windmills typically have 4 blades, yet all modern wind turbines have 3?

In: 9124

Answer 1

Right angles are really easy to make with pre-industrial tools. Since a mill needs to balance pressure on all the blades (or they are more likely to break in heavy wind) the easiest way to balance is two beams crossed at right angles.

Answer 2

Right angles are really easy to make with pre-industrial tools. Since a mill needs to balance pressure on all the blades (or they are more likely to break in heavy wind) the easiest way to balance is two beams crossed at right angles.