WIND TURBINES - Why Do Wind Turbines Have Three Blades? - Three blades make the whole component cost effective. If 4 blades are put instead of three blades, it will ultimately increase the cost of a wind turbine, thereby making it less cost-efficient. Putting four blades of size equal to that of a three-blade wind turbine will make it heavier. Although two blades are the minimum requirement to balance the turbine and harvest maximum energy, it has its own negative effects. A two-blade wind turbine can match the power output of a three-blade wind turbine if we increase the length of the blades by 50% which ultimately increases the cost of the turbine. Moreover, it will also increase the height of the mast for providing more ground clearance.

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Wind Turbines

Why Do Wind Turbines Have Three Blades?

engineeringinsider

Have you heard about wind turbines? Most of you must have and probably seen one too.

Whenever you get to drive by a farm, you get to see them.

A wind turbine is a set up to harvest wind energy. It converts the wind’s kinetic energy into electric energy.

The wind’s kinetic energy helps in the rotation of the blades of the turbine which ultimately rotates the rotor to which they are attached.

The rod is linked to a shaft which sets in motion a generator to produce electricity.

Wind turbines have been in existence for a longer time. Earlier they were used for pulverizing grains and pumping water, but, nowadays, there use is mostly limited to generating electric energy.

Over the years, they have undergone a huge change. From being available in various shapes to down to the turbines with only three blades.

Ever wondered why a wind turbine has only three blades?

There are various reasons behind its appearance. Let’s discuss them all one by one.

Firstly, three blades make the whole component cost effective. If 4 blades are put instead of three blades, it will ultimately increase the cost of a wind turbine, thereby making it less cost-efficient.

Moreover, putting four blades of size equal to that of a three-blade wind turbine will make it heavier.

Why can’t we use wind turbines with only 2 blades? –

Then another question arises that why can’t we use a wind turbine with only 2 blades?

Each blade of a wind turbine helps the following blade in rotation by disturbing the air so you want to keep a minimum number of blades.

Although two blades are the minimum requirement to balance the turbine and harvest maximum energy, it has its own negative effects.

A two-blade wind turbine can match the power output of a three blade wind turbine if we increase the length of the blades by 50% which ultimately increases the cost of the turbine.

Moreover, it will also increase the height of the mast for providing more ground clearance.

We can also increase the rotational speed of the two-blade wind turbine by 22.5% to match the efficiency of a three blade wind turbine.

This will spin the blades faster but it is entirely difficult. Rotating blades of a wind turbine make noise.

So, when the blades of two-blade wind turbine rotate faster, they make more noise. We know that people don’t like living in a noisy neighborhood.

So, we can’t increase the speed of the blades as it will be very disturbing for the people living in the surrounding area.

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