How Do Wind Turbine Farms Work?
Have you ever wondered how the electricity we use at our homes and offices is generated?
Let me guess. Your answer might be through solar, water, or geothermal sources, but there is another way to produce electricity, i.e., wind energy.
Wind energy is a renewable and clean energy source produced by wind speed through various atmospheric changes.
Interestingly, the United States of America has seen a massive jump in electricity generation through wind energy in the past years, which was 6 billion kWh in 2000 and has increased to 380 billion kWh in 2021.
Wind turbines are a modern version of windmills with air propellers that catch the wind and rotate them, turning them into power, which is then transferred to the generator and released into the defined national grid for a specific area and sent to homes and businesses.
To put it simply, wind turbines work exactly opposite to a fan. While a fan uses electricity to produce wind, in turbines, the propellers produce electricity when hit by the wind. These turbines rotate up to 20 revolutions per minute depending upon the speed of the wind and technology. The energy produced by wind turbines depends on air density, wind speed, and the area swept by the air propellers.
These wind turbines are of two types:
1. Horizontal-axis wind turbines: The blades of these turbines are oriented in the direction of the wind and spin on the horizontal axis. The rotor and the generator are placed at the top of the tower. These turbines are suitable for high wind speeds because of their robust construction.
2. Vertical-axis wind turbines: The blades are vertically oriented. Unlike the horizontal axis, the generator and gearbox are placed on the ground and are used in variable wind conditions.
What is a wind turbine farm, and how does it work?
Wind farms, also called wind parks, are a cluster of wind turbines connected to a voltage transmission system built with the capacity to generate vast amounts of electricity.
Like any other atmospheric conditions, there’s no guarantee of having a fixed wind speed. Therefore, the wind farms differ based on needs, location, the direction of the wind, etc. . As per the experts, an average annual wind speed of at least 9 mph is the minimum speed for power production.
Two Different Types Of Wind farms:
1. Offshore wind farms: An offshore wind farm combines power plants in shallow water areas far from the coastline and marine traffic routes. Wind energy is obtained using the force of the wind produced on high seas. The crucial elements of the offshore wind farm are cables, wind turbines, and substations.
2. Onshore wind farms: On the other hand, onshore wind farms are located in fields or rural areas that are less populated and have low habitat value. The installation does not require advanced technologies and is less expensive. One of the most significant disadvantages is that they produce less energy due to the low wind speed and natural landscapes such as hills, towers, etc.
Working on Wind Turbines
Wind farms operate through aerodynamic forces, where the air pressure between the blades causes the blades to drag and spin. The process of wind turbines is as follows:
1. These large blades and the hub enable the rotor to capture kinetic energy. The blades are pointed toward the wind.
2. Further inside, the main body of the turbine located on the top of the tower has a gearbox that helps convert the slow-speed rotation of driver shafts into high-speed. This high speed is transmitted to the generator that produces electricity.
3. Then, the produced electricity flows down the inside of the tower.
4. Moving on, the voltage is raised or reduced by the transformer to transport the electricity. When a large amount of current is transmitted over long distances, voltage is increased, eventually decreasing the power losses. It is decreased when electricity reaches, so it is safe for the community to use.
5. Electricity generation: The electricity then runs through the cables in the turbine tower and goes through an underground line to a substation where it converts the electricity into higher voltage and finally transfers it to the national grid and gets distributed to the points of consumption points.
6. The anemometers provide the measurements of the velocity of the wind and its direction, used to adjust motors, nacelle, and towers to optimize the wind speed.
What is wind farm equipment?
Rotor Blades: There are three or more rotor hollow blades that are light and strong. These rotating blades operate as same as aircraft wings. There are two wings, one flat and one twisted, which helps create a difference between atmospheric pressure.
Nacelle: The nacelle is placed on the top of the tower and contains the most important components of wind turbines that are crucial to the electromechanical process that goes into the working of wind turbines, like the generator, high-speed shafts, brakes, and gearbox. Due to this reason, a nacelle can weigh over 300 tonnes and be over 50 feet tall.
Gearbox: The gearbox is primarily used to increase the speed, i.e., revolution per minute, of the main shaft to suit it for the generator. Please note that the larger the blades of the turbines, the lower the speed, while increasing the speed of the blades can put pressure on blades and even increase noise, and this gearbox comes to the rescue.
Tower: It is made up of tubular steel that supports the rotor and nacelle as the structure of the turbine. The turbine tower is made similar to the diameter of the circle that the blades make as they spin. It comes in three sections:
1. Lattice towers
2. Tubular steel towers
3. Hybrid towers
Aerometer: This is used to measure the wind speed in the wind flow tunnels and atmosphere.
Electronic equipment: This equipment comprises sensors and grid infeed systems that measure direction and temperature for monitoring and control.
Generator: The generator works on converting mechanical energy into electrical energy and creates changes in the voltage that acts as a driving force for the subsequent current passed through the devices.
What is a wind farm substation?
Wind farm substations act as an interface between electricity generation, transmission, and distribution and is a high-voltage electric system facility. They are constructed to control and absorb the excess energy produced and stabilize the power generation over large generators.
Wind farms substation consists of various equipment:
1. Voltage systems
2. Auxiliary services
3. Fire protector and communication system
4. Transmission cables and generators
The continuing advancement of wind farms indicates a low carbon footprint future, but more is needed to achieve the goals so soon. However, setting up a wind farm can be a complex task. It requires the precise placement of turbines, securing transmission capacity, choosing the perfect area with the proper wind flow, and installing and testing equipment.
Wind Turbine Farm Frequently Asked Questions
How do wind turbines store energy?
Energy can be stored through the aid of charged batteries or by deploying solid-state batteries with enough storage capacity of at least 30- 45 days. The other methods to extract new power are pumped hydroelectric storage dams, compressed air storage, rail energy storage, ultracapacitors, etc. Sometimes, power can be sold to the utility company or other sources when excess power is produced and available.
How do wind turbines work without wind?
Wind turbine blades can turn even if it is slightly windy, and it takes hours to slow down a turbine that starts turning due to a little wind. The other situation can be that power is extracted from the grid during the cold season to rotate the blades so that blades and gears do not freeze up. It eventually leads to the generation of a small amount of power despite the wind no more flowing.