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

Modern wind turbines go for a couple things.

1. Amount of wind captured.

2. Manufacturing and construction cost.

3. Stability

So for 1 more blades is better. But 3 blades capture almost as much of what 5 or 7 blades do. This doesn’t affect capacity as much as say the height of the turbine.

For 2. Less blades is better. Less connections. Less failures. Less shipping cost. Less Manufacturing cost.

There’s prototypes with more blades but don’t usually get Mass produced.

For 3. Odd number of blades gives lateral stability so it doesn’t swing back and forth and fall over.

So 3 blades is what gives the best economic payout for your wind energy buck.

Answer 2

Modern wind turbines go for a couple things.

1. Amount of wind captured.

2. Manufacturing and construction cost.

3. Stability

So for 1 more blades is better. But 3 blades capture almost as much of what 5 or 7 blades do. This doesn’t affect capacity as much as say the height of the turbine.

For 2. Less blades is better. Less connections. Less failures. Less shipping cost. Less Manufacturing cost.

There’s prototypes with more blades but don’t usually get Mass produced.

For 3. Odd number of blades gives lateral stability so it doesn’t swing back and forth and fall over.

So 3 blades is what gives the best economic payout for your wind energy buck.