When I was recently reading an article about methods of generating wind energy, I started to wonder how energy is actually formed from the wind. So, I did some more research to find out the details about how wind energy is formed.
How is wind energy formed? Wind energy is formed by a machine called a wind turbine. The wind turbine is composed of multiple parts that work together to capture the wind’s kinetic energy and transform it into electricity internally.
Wind turbines go through a much more complex process to transform energy into electricity than just spinning their blades in a circle and making it appear in front of them. While it is true that turbines are efficient and can quickly generate electricity that is used for large amounts of people, there is more to the entire process than meets the eye.
How Wind Is Formed and Used
The wind is one of the earth’s natural processes that occur in all areas of the world at different times of the year. The wind is formed due to an unequal distribution of heat energy that is given off by the sun in rotation throughout the solar system.
As a result of the imbalance in the sun’s energy, the warm air begins to grow and expand until it becomes elevated. While this entire process is happening, the cold air that is already present in the earth’s atmosphere will slip through the warm air and begin to sink to the bottom toward the earth’s surface. These events cause a flow of air between them as they separate themselves, also known as wind.
Although it is true that the wind is a natural process that will never cease to exist, the patterns in which it will appear in different areas of the world is never entirely predictable.
The weather conditions can always be predicted, but this usually isn’t possible until very close to the time that is in question. As a result, there are certain limitations in place as to how much wind energy can really be extracted from the earth throughout the entire year.
It has been reported that the average wind turbine will be effectively taking in the wind’s energy and converting it into electricity approximately 85 percent of the time that it is in use, with most turbines carrying out a total life cycle of around 20 to 25 years at maximum.
Although these efficiency rates are accurate, there are other limitations to how much energy can really be extracted from the wind at one time, no matter how fast the blades are spinning. This concept, formally recognized as Betz’ Law, states that wind turbines only have the capacity to extract 59.3 percent of the wind’s energy at any given time that the blades are in rotation.
The Components of a Wind Turbine
Before diving into the topic of how wind turbines collect energy from the wind, it is important to be familiar with all of the components inside of the machines. There are four main parts of a wind turbine that hold all the individual parts that do most of the work inside of them.
The largest part of the wind turbine that holds the most components under its shell is known as the nacelle. The nacelle is the large, oval-shaped piece that sits directly behind the blades that rotate when the wind blows in their direction. Some of them are actually large enough to hold a community swimming pool on their surface.
The main components that work together inside of the nacelle to create energy from the wind are the gearbox, generator, low-speed shaft, high-speed shaft, and controller. The low and high-speed shafts are the components within the turbine that determine how fast or slow the blades will spin.
After the controller indicates the appropriate speed for the wind turbine to rotate, one of these shafts will come into play depending on if the wind speeds are faster or slower at that given time.
The generator and gearbox both work together to spin the wind’s energy around within them and essentially make the energy stretch as far as it can. The main goal of a wind turbine’s components is to generate as much electricity from the wind as it possibly can whenever it is able to extract energy from it.
The next main component of a wind turbine is the rotor blades. This piece of the turbine consists of the rotor that is attached to the spinning blades and the circular rotor hub that sits in the center of the turning pieces.
The main purpose of the rotor hub is to essentially suck in the kinetic energy from the wind and transport it through to all of the other components inside the nacelle so they can convert it into electricity.
The blades on the turbine will spin around their base according to the speeds of the wind. If the wind speeds are too low or too high, the blades will receive a signal that they should not resume their spinning function because they will either not be able to collect any energy or could possibly suffer severe damages from extreme weather conditions.
The inner components within the nacelle that is located behind the rotor blades will send a message forward indicating when the blades should start and stop spinning.
The remaining components that make up a wind turbine are tower piece, which is the tall stick that sits directly underneath the rotor blades and nacelle components. The tower essentially holds the entire turbine up and keeps the blades in the path of the wind where they can collect the most energy and achieve the highest efficiency possible.
The tower can be designed in a variety of patterns, including the most simple cylinder shape as well as a more complex interlacing lattice fashion. Regardless of the tower’s design, it is a piece that is essential to the functioning of the wind turbine.
The tower piece is also connected to the electrical cables that run through the ground underneath the turbine and create a path for the electricity to travel and be prepared for distribution.
The final piece that makes up a complete wind turbine is the foundation. Just like anything that is built from the ground up, turbines require a solid foundation to keep them standing upright and to keep them from falling over when bad weather conditions occur.
These foundations are commonly made out of concrete that is poured into a hole in the ground, however, some turbine foundations can alternatively be made out of an extension of steel that sticks out of the ground, or from the bottom of the ocean for offshore turbines that are located in the ocean.
Although the foundation is often not visible on the outside of the turbine for those located onshore, it is another piece that is essential to the functioning of the turbine. Without a solid foundation, the wind turbine would fall over too easily in the event of a storm or other severe weather conditions.
How a Wind Turbine Collects Energy From the Wind
The process of collecting energy from the wind begins when each individual wind turbine picks up on appropriate speeds to begin spinning their blades. Each turbine is automatically programmed to stay within a certain limit that consists of a minimum and maximum possible speed in which it will turn its blades.
These speeds are known as the cut-in and cut-out speeds. The speed of the current wind is calculated by a small piece that sits on top of the turbine called an anemometer. The anemometer is a tiny spinning component that gets pushed by the wind and is able to gauge the exact torque that is being given off by its force.
When the wind is blowing at a sufficient speed to where the turbine is able to collect its energy but it will not cause any damage to the blades, the anemometer piece that sits on top of the nacelle will begin to spin around and let the inside of the turbine know that it is the prime time to collect energy.
This message is passed through to the nacelle, which is one of the largest components on the entire turbine that houses multiple smaller parts on the inside, to another working part known as the controller.
The controller’s function is basically exactly what it sounds like. It controls the exact speed that the wind turbine will rotate its blades in order to achieve maximum energy efficiency. In other words, the controller makes sure the rotor blades are spinning just as fast as they should be so they can grab as much of the wind’s energy as they possibly can at that given time.
Once the controller pushes the anemometer’s message forward toward the blades, they will begin reacting to the speeds of the wind and spinning around their axis accordingly. Faster wind speeds will always translate to faster turning speeds, and the more wind there is the more energy can be consumed and transformed by the wind turbine.
The specific type of energy that is taken from the wind by a turbine is called kinetic energy. Kinetic energy is created when there is any type of movement, such as the action of the wind blowing in a certain direction.
This energy will exert a force on the turbine’s blades, creating a friction between the blades and the atmosphere which causes it to begin rotating. This action that the wind performs on the blades is also known as lift.
What Happens to the Wind’s Energy After It Enters the Wind Turbine
Once the wind’s kinetic energy is sucked into the center of the nacelle, it is consumed by the turbine’s generator. Inside the generator component, the wind’s kinetic energy is combined with the potential energy of the machine and is exported in an entirely new form also known as mechanical energy, which is essentially the sum of both types of energy that existed before it was created.
The energy is converted when it is spun through a series of tightly coiled loops of copper within this component. Throughout the entire process of the wind’s energy being transformed and changed into electricity that can be distributed for use, it will pass through the turbine’s entire body and undergo a series of functions before it can be exported.
During the time that these functions are being carried out, the energy that was harnessed from the wind will be multiplied several times by various components inside of the nacelle piece.
This must be done in order for the machine to create as much electricity as it possibly can from any amount of wind power that is given to it. When the mechanical energy has been transformed and multiplied as many times as necessary, it will undergo yet another transformation.
While this new transformation is going on, electrons will be sparked and created within the existing energy in order to turn it into usable electricity. The voltages of the electricity are multiplied again several times from the moment it is created to when it is distributed and received by the consumer that will be putting it to use.
In conclusion, the process of extracting energy from the wind and converting it into electricity is not as simple of a task for the average wind turbine than it may seem to be. From the outside, wind turbines look almost like small pinwheels that are just reacting to the wind and spinning around aimlessly along with it.
However, this statement couldn’t be much farther from the truth. Wind turbines undergo a series of complex processes within them from the time the wind’s energy enters through the rotor hub to the final transfer of the newly created electricity along the power grid when it finally reaches the consumer.
How Does a Wind Turbine Transport the Electricity for Consumers for Use?
After a wind turbine has successfully transformed the wind’s energy into usable electricity, it will travel a long distance from the machine to the actual consumer that will use it to power their facility.
To begin this process, the electricity will slip down the tower of the wind turbine and enter into a network of thick underground electrical cables. It will then travel through the ground until it reaches a location known as an electrical substation.
The substation is the middleman between the wind turbines and the people who will receive the electricity that was created by them. From there, the electricity will travel through more cables on something called a power grid, until it reaches its second to final destination.
At this location, the voltage will be decreased slightly to prepare it for distribution, since it had been increased frequently through the process of transportation. After this step has been completed, the electricity is ready for distribution to consumers.
Will the Wind Always Blow and Provide a Sustainable Source of Electricity?
Yes. The wind will always blow and provide a sustainable source of energy for the remainder of the time that the sun is out and the earth is in existence. As a natural and renewable source of energy, there is no need for constant replenishment of the wind like there is for certain non-renewable energy sources such as coal and fossil fuels.
Even though the wind is not entirely predictable, anyone who uses wind energy as a primary source of electricity will never have to worry about it becoming a depleted resource.
Additionally, there is no way for humans to ever take control of the earth’s supply of wind in order to regulate it or distribute it from one single source. As a result, the prices of wind energy will always be lower than other sources of electricity because it is essentially free for anyone to use.
What Happens To Wind Powered Areas When There Is No Wind?
Even though there is an infinite supply of wind on the earth, there will be some days throughout certain seasons that are not as windy as others. There also might be some days or entire seasons out of the year where there is absolutely no wind at all. As a solution to this problem, there is a process called Compressed Air Energy Storage.
The overall purpose of this process is to store the excess energy from the wind on extra windy days where there is more energy than what is needed at that given time.
To do this, the extra wind energy will usually be pumped underground into a large cavern that has the capacity to hold huge amounts of air at one time.
The energy will go through a series of components, similar to the process inside of a wind turbine that was explained earlier, where it is multiplied and heated up before released into the atmosphere and used on days where there might be a shortage of wind but more energy is needed.
If you’re serious about learning more about wind energy, I recommend the Wind Energy Handbook on Amazon. This book is great for both students and professionals, and it holds invaluable information on the subject of wind power.