Wind energy is an important renewable source and is very popular in Ukraine and in the world. Focus will tell you how it is obtained.
Wind turbines are called “windmills of the third millennium”. They use air currents to produce a valuable resource: electricity. About how they are arranged and how they work.
The modern wind turbine was invented by Scottish electrical pioneer James Blythe in 1887. He built a windmill to light his holiday home. The shape and size of his turbine were significantly different from modern ones. It was 10 m high and consisted of a wooden tripod tower, semi-cylindrical canvas sails and a vertical main rotor shaft. Since then, the design has been slightly modified and the mechanisms have become more complicated, but the principle of operation has remained the same, which will be discussed below.
What is a wind turbine
Wind turbine or wind generator — it is a device that converts the kinetic energy of the wind (a natural and renewable source) into electricity. While a fan uses electricity to create wind, a wind turbine works the opposite way: it uses the wind to generate electricity, writes Enel Green Power.
The taller the turbine, the stronger the wind, as there are fewer obstacles in its path. The blades of the turbine, which are similar to aircraft propellers, use the aerodynamic force of the wind to spin a rotor, which in turn spins a generator. This process produces electricity, which is then fed into the grid.
Wind turbines that transmit electricity to the grid are based either on land or at sea. Conglomerations of wind turbines are known as wind farms. In 2022, wind energy accounted for 7.33% of global electricity production, and this figure is growing every year.
The popularity of wind energy is due to the fact that, unlike electricity generated from fossil fuels, it does not pollute the environment.
Like most types of complex equipment, wind turbines must be inspected, cleaned of debris, lubricated by applying a consistent grease or oil, and repair.
Types of Wind Turbines
There are two main types of wind turbines: horizontal-axis and vertical-axis, reports Energy Follower.
< h3>Horizontal-axial wind turbines
Horizontal axis wind turbines (HAWT) are the most common and most efficient type of turbine. They usually have three blades and operate “upwind”, meaning that the blades face the wind. This is due to the fact that the HAWT head can turn thanks to the tracking control system (we will talk about this below. — Ed.). The main components (for example, the generator) are located at the top of the installation.
Wind turbines with a vertical axis of rotation
As the name suggests, vertical axis wind turbines (VAWTs) have a vertical rotor shaft, and their appearance is quite different from HAWTs.
VAWTs are omnidirectional, so they do not need to be adjusted to point into the wind: this can be an advantage in places where the wind direction is very variable. However, they are relatively rare because they are less effective in terms of air resistance. The main components are located at their base.
200% Deposit Bonus up to €3,000 180% First Deposit Bonus up to $20,000Main components of a wind turbine
The devices consist of several components, which were detailed in the Wind Power Plus publication.
Foundation. It is a large, heavy structural block of concrete that supports the entire structure and the forces acting on it. In marine turbines, the foundation is placed under water.
Tower made of steel, although wood (which is generally considered less harmful to the environment) can also be used. The structure consists of three sections and is assembled on site. Its height varies, but usually it coincides with the diameter of the circle created by the blades during rotation. The tower also contains power cables connecting the nacelle to the transformer on the ground.
Gondola located at the top of the tower and can rotate 360° around its axis depending on the direction of the wind. It is named after the part of the wing of the plane in which the jet engines are located. It houses the main mechanical elements: gearbox and generator.
Rotor and hub. Two-bladed rotors are cheaper and faster than three-bladed rotors, but they are also louder and vibrate. As in the case of airplane propellers, the hub — it is the nose, the blades are attached to it, and it, in turn, is connected to the mechanical parts in the nacelle behind it.
BladesTurbines are located on top. The average length is 52 m. The wind reduces the air pressure on one side of the blade, and the difference on the other creates both lift and drag: when the lift is greater than the drag, the rotor will rotate.
How wind turbines are built< /h2>
The construction process is complex and requires both coordination and precision, the Earth Eclipse article explains. Various components are manufactured, and then they are brought to the installation site. First, it is necessary to assemble the tower, after which the gondola and its contents are placed on it, and then — blades Last but not least, install the switchboard and electrical system.
The process is quite simple. The rotor drives the wind. Its rotation is transmitted to the input shaft, which feeds the electric generator. This so-called yaw control system allows the nacelle to be positioned depending on the direction of the wind. The rotor starts working only at wind speeds above 10 km/h, while the wind turbine shuts down at speeds above 90 km/h for safety reasons.
How a windmill works and how much energy it generates
Wind turbines are designed to face one direction. This enables them to maximize their efficiency in using wind energy. This arrangement, with the turbine blades facing directly into the oncoming wind, optimizes the capture of kinetic energy, ensuring efficient conversion into rotational motion that drives the generator to generate electricity.
Essentially, the kinetic energy of the wind is converted by the rotor on mechanical energy. The gearbox speeds up the slow rotation of the blades, from 18 to 25 revolutions per minute, to 1,800 revolutions per minute, which can power the electric generator. An electric generator converts mechanical energy into electricity. The transformer transfers electricity from one circuit to another, changing its characteristics.
The average electrical power of a wind turbine is 2-3 MW, which enables it to produce more than 6 million kWh of electricity per year, summarizes Enel Green Power.