How Do the Wind Turbines Work?
Have you ever got interested in wind turbines? Just like me, are you wondering how do they actually work? Then you are at the right place. Wind turbines are almost free of cost, renewable, and sustainable source of energy.
While visiting France, I passed through a windfarm. From that very moment, it made me think how do they actually work? So I did a little digging on the internet and gathered as much information as I can.
I was pretty shocked to know how simple the process was. Mainly the turbines turn the wind flow to electric energy. Developed countries like France, the United Kingdom, China, and so on use windfirms as their main source of energy.
Alriht, enough of chit chat. If you want to know about the mechanisms of wind turbines, bare with me and go through this writing.
What Parts does a Wind Turbine Have?
You already know that wind turbines have propellers similar to aeroplanes, and are attached with the peak of a tower. The propellers can be up to 60 meters long made with very light and resistant material.
However, he main body of the turbine is called Nacelle. Usually, each wind turbine contains three propellers, which keep rotating due to the wind. It has a wind vane at the top. That indicates wind direction.
Accordingly, the blades or the propellers are attached to the main machine or turbine through the hub. That is coupled to the low-speed shaft attached with a gearbox.
At the same time, the gearbox increases the speed that is gained and transfers it to the high-speed shaft which is connected to a generator. Then the generator transfers the produced energy to the base of the tower.
On the other hand, the transformers are planted on the base tosend the transformed energy to the substation through underground cables.
The Actual Working Method of a Turbine
Wind turbines are helping us to use the force of the wind by converting it to electricity for a very long period of time. This is being possible because of the propellers. Engineers designed the propellers of a wind turbine using aerodynamic analysis. So the question remains how do they work actually!
Well, first of all, if the force of the wind is successful to turn the propellers around, we will be able to receive electricity from the generator connected to the turbine.
Each blade contains many aerofoil cross-sections. When an aerofil shaped blade moves through a fluid, it produces a huge amount of aerodynamic force or lifts force. Due to this lift force, the wind turbines keep rotating.
However, the achieved rotation cannot be directly sent to the generator to create electric power. The reason behind this is the wind turbines rotate pretty slowly, which means it has a low rate of revolutions per minute.
Taking the low speed rotation into consideration, you can understand that the generator cannot produce a significant amount of electricity from this speed. The low speed shaft transfers the rotation to a gearbox.
Then the gearbox increases the speed in a huge manner so that the generator can get the highest possible speed to generate power. Later on the speed is sent to the generator through the high-speed shaft from the generator.
Likewise, the produced electricity is transferred to the base of the wind turbine tower through some cables where there is a step up transformer. However, the blades should always face the wind direction, but we cannot really know the exact wind direction every time as it keeps changing.
Therefore, a mechanism called yaw is used to keep the blades rotating against the wind direction.
To summarize, the basic mechanism here is the wind force. This rotates the blades and the blades fully capture the energy from the wind flow. The blades can rotate with a speed of 11 kilometers to 90 kilometers per hour. The low-speed shaft has the same speed as the blades.
It is necessary to increase the speed to produce electricity so that the gearbox can multiply the speed and transfer it to the high-speed shaft. The high-speed shaft rotates up to 1500 revolutions per minute and sends it to the generator.
Consequently, the generator converts the kinetic energy into electricity and the electricity produced here is the direct current (DC). The transformers planted at the base of the tower turns this DC into alternating current (AC).
In addition, the transformer also raises the voltage. From each turbine of the farm, AC is sent to the substation, and the substation increases the voltage again and sends it to the electricity grid.
How Efficient a Wind Turbine is Scientifically?
Efficiency of a wind turbine is a fascinating thing to discuss. You will be surprised to know that no wind turbine in this world is a hundred percent efficient. It cannot turn the whole energy gained from wind flow to electricity.
Besides, you already know that the blades absorb kinetic energy from the wind and turns that into electricity, but it cannot absorb the whole gained energy.
There are two types of wind speed, upstream and downstream. The downstream speed is really less than the upstream speed. As a matter of fact, wind turbines can only absorb the whole kinetic energy if the downstream speed is zero.
However, zero downstream wind speed is a physically impossible condition. As the downstream wind speed can never be zero, a wind turbine is only up to 60% efficient.
Pros and Cons of a Wind Turbine
Nothing in this world is completely perfect. Which means, even though being a green way of producing electricity, wind turbines also have some cons along with pros.
I think by now you know everything that you needed to. Wind turbines really can be the energy generator of the future even if it is a bit expensive because we can not afford any sort of pollution at this point in our environment.
On the other hand, turbines do not harm nature by any means. Despite the fact that it is expensive, it can allow us to generate electricity in a greener way.