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Wind turbine is a technology that converts moving air into electricity. Energy is practically harnessed from the motion of air.

Understanding the inside of a Wind turbine

Generating electricity from wind is relatively simple. All effective wind turbines have often 3 blades that are aerodynamically architectured to easily create a rotating movement as air blows. The blades spin a shaft that is linked to a generator that creates the electricity.

The rotation mechanism – When the wind blows, the blades create a lift, similar to the wings of airplanes and the blades begin to rotate. When the blades rotate, a low-speed shaft is spanned 30 to 60 times in a minute. This low-speed shaft is connected with a gearbox or a high-speed shaft that accelerates the rotation to 1000 to 1800 rotation in a minute. The high-speed shaft drives the generator and produces electricity. The generator is then connected to an electric power grid.

Generating the Power

Four factors determining the electricity capacity of a wind turbine is wind velocity, tower height, air density and blade radius.

Wind velocity determines energy generated. Wind is never even, sometimes strong and other times weak. However, wind turbines do not operate in too strong or weak winds. If the speed is too low, for example, below 8 miles per hour the turbines will not work. The ideal speed is winds in the range of 25 to 55 mph. If the wind goes above 55mph the turbine is switched off as damage can be caused.

A tall turbine is usually more efficient. There are two reasons for this, being that more winds can be captured at higher altitudes and there is less turbulence (winds are more constant).

Air density determines the kinetic energy of winds. The more dense the winds the more capacity do they have to propel the turbine to turn. In high-altitudes the air pressure is lower, in other words the air is lighter and is thus less effective location for wind turbine to operate. In lower-altitudes such as near the sea level, the air is dense and heavy making it much more effective to turn the wind turbine.

The radius of the blades determines the amount of wind that can be harvested. A large blade will be able to yield much more wind and thus the diameter of the blade can as substantially establish power levels.

Source: National Geographic