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

Old windmills were made before you could consistently make things the exact same size and weight. In order to balance a three-bladed windmill, you have to make each blade weigh the same, otherwise the heavy one will fall to the bottom. To balance a four-bladed windmill, you just have to make two spars, find where the balance point is at the middle, and attach each one to the axle at that point.

Answer 2

Old windmills were made before you could consistently make things the exact same size and weight. In order to balance a three-bladed windmill, you have to make each blade weigh the same, otherwise the heavy one will fall to the bottom. To balance a four-bladed windmill, you just have to make two spars, find where the balance point is at the middle, and attach each one to the axle at that point.