Why most wind turbines have three blades instead of four and two?

Wind energy industry is rapidly growing. Together with solar energy they currently represent the two fastest growing renewable energy industries in the world. Wind turbines are located not just on land but also offshore and are becoming common sight in many countries of the world.

But what about wind turbine design in terms of number of blades? Did you ever wonder why most wind turbines have three blades instead of two or four?

If wind energy developers would to use two wind turbines instead of three, the turbine would be faster, and more speed in most cases results in increased energy output. However, using two wind turbines instead of three would make turbine far noisier and that would be serious downside, because some people even argue that turbines with three blades contribute to noise pollution let alone two.

And why not use four blades instead of three? Well, blades cost lot of money so using four blades instead of three would significantly add to overall costs of new wind energy projects.

In this sense, turbines with three blades are really the most balanced solution in three very important areas: efficiency, costs and noise. Future designs may come up with different solutions, not only in relation to the number of blades but also with the size and the location.

But for now, there are turbines with three blades that dominate the wind energy market.