The wind is a natural form of energy which gives a technical potential considering its speed. Today, wind energy is considered one of the fastest-growing technologies in the world. This is mainly not only due to the abundant and inexhaustible nature but also due to its coexistence with nature, forcing no harm to the environment. At present wind energy mostly contributes towards power production. Offshore and onshore wind farm projects are the main energy-providing types in this section, harnessing the motivity of wind with the help of tall turbines and large rotators. But have you ever wondered what happens to wind energy after it’s been harnessed by these large wind farms around the world? How did this wind energy approach your light bulb at the end? In this blog, we are going to take you on a journey to uncover the essential steps that are taken from capturing wind energy and distributing it as usable electricity.
How is wind energy captured?
The wind turbine has a specific structure which is significant in power generation from wind energy. From the outside, we can observe the structure which is specified for capturing the wind.
So that it is made with 3 or 4 turbine blades from steel, titanium or aluminium connecting to a rotator. This system is on top of a long tower which is constructed to hold the blades and the system off the ground near the wind-concentrated area.
These towers are usually fixed to the ground. Offshore wind turbine towers are connected to the bottom of the water body. Today researchers are trying to develop a tower on top of the water’s surface, to float on water.
The three turbine blades are kept in a way to keep the angular momentum constant so that when one blade is up the other two are pointing at an angle to rotate with wind smoothly.
These blades can be either flat, rounded or curved on the vertical axis.
Rotor blades (turbine blades) act similarly to the aircraft wings which creates a pressure difference on either side of the blade, in a way that one side of the blade is flat and the other is curved. This captures the wind which connects to the rotator next.
How is the power generated from this captured wind?
Nacelle, the heart of the wind turbine involved in converting aerodynamic force from the blades to electrical energy. It is normally housing for the generator, shafts, gearbox and brake.
The low-speed shaft that is connected to the rotor spins about 8-20 rotations per minute.
However after it met the gearbox, the rotations increased a big difference making 1200-1800 rounds per minute.
This rotational speed is enough for the generator to provide electricity. The theory of changing the magnetic field around a coil is applied here. However, this DC current formed by the generator is then extracted that is converted into AC current by the Converter.
This power-generating procedure should be maintained at a specific level. Especially, the turbine blades must not exceed the level of 1000 revolutions per min. After that level, the friction will be increased the inside of the system and may cause the wind turbine to explode or even cause some long-term damage.
To avoid these types of damages, wind turbines have been installed with some mechanisms.
The electronic device of the wind turbine can detect the speed of the power output and stimulates the pitch system to take off. The pitch system can change the angle of the blades, turning the blade slightly out from the wind when the power output is high. Conversely, when power output is slow it does the opposite.
How is Energy storage done in wind farms?
The next important step in the pathway is to store excess electricity formed by the generator when there is low wind energy or high demand which may occur later. There are many variations of storage of excess energy in variable forms.
The excess air can be stored by compression from the turbine and stored in underground cravens or above-ground tanks. When there’s a low supply of wind, this stored wind energy can be used directly on an air motor or it can act as a combustible source to form mechanical energy with fuels to activate the generator.
Furthermore, wind energy can be stored in hydrogen fuel cells where Hydrogen is formed as a result of the electrolysis of water with the aid of wind energy. Then these Hydrogen fuel cells can be activated to form electricity using a fuel power system. Apart from that electricity batteries, especially lead acid batteries can be used to store excess energy and electricity can be obtained in a well efficient manner.
There are types of battery systems which are applied in this area. They are DC battery systems, AC battery systems and Hybrid systems.
DC battery systems are directly connected to the wind turbine without an inverter. On the other hand, AC battery systems do require inverters as they have access to the AC current only. The hybrid battery system has a more efficient impact as it contains both AC and DC access.
Distribution and utilization of Wind energy.
This is the destination of the wind energy that is captured in wind turbines. The converted electricity must be distributed so that it can be utilized to perform many tasks.
The energy can be distributed through electrical grid distribution where the load is distributed through transmission or distribution lines where it is directed to local sites or the other end user. When local sites get this distributed load it can be reduced by substations to a suitable amount for the user and then it is connected to the transformers which further reduces for safety purposes.
Furthermore, there are some direct distributions of the converted wind energy which is done by onsite generation. This does not require extensive distribution as it can form electricity near the area of consumption. This system is mostly applicable in factories or business areas. Microgrids are the common structure which is independent of the main grid for distribution.
Another method is decentralized systems which may be either by stored wind energy systems or small-scale wind power generating turbines. This is mainly received by isolated residences or houses.
Distributed power can be used in many areas for utilization. The product of wind energy is used for different requirements of residential, commercial and industrial sectors. The electricity cost for these consumers is relatively low when compared to non-renewable energy resources. Plus with the application of technology, the required demand can be fulfilled by wind farms. By using current by wind energy we can contribute to the reduction of using fossil fuels which release many pollutants.
In developing countries, or rural communities the instalment of stand-alone systems of wind turbines can electrify the area with the aid of microgrids for distribution. Basic electricity necessities such as lightning, communication and basic applications can be fulfilled by this method. It also aids in providing a much quality of life by providing electricity to schools, hospitals, libraries and houses.
Wind energy can be used in the electrification of transportation. This means simply that wind turbines can be used to charge an electric car. Thus the power is generated when a vertical axis wind turbine is kept inside the front grille of the vehicle where there is airflow.
Conclusion
From winds to Watts the wind energy goes along a journey from capturing, converting, storing and distributing to utilizing. This proves its value to the environment as a non-harmful, inexhaustible energy resource, but also proves its importance to communities as a sustainable, developing and comparatively cheap energy source.
Electricity from wind farms is a popular trend which is used in both developing and developed countries. By capturing and converting to current with the correct use of technology and infrastructure, well planning and following innovative strategies to ensure a reliable and constant supply and use of correct technique to distribute with protective strategies, the current of wind energy finally reaches the end user. The distribution of this electricity contributes positively to the quality of life of certain communities in rural areas or developing countries, contributing to the social and financial development of a society.
