In the world of renewable energies, two key forms of generation stand out: solar energy and wind powerWhile solar energy transforms solar radiation into electrical energy using solar panels, wind energy focuses on harnessing the power of the wind using wind turbines. These devices are essential for converting the kinetic energy of the wind into usable electrical energy.
The wind turbines They are complex in design and require prior studies to ensure that their installation is profitable and efficient. There are various types and technologies associated with wind turbines, which vary according to their use and electricity generation capacity. In this article you will learn in detail everything related to wind turbines.
Characteristics of a wind turbine
Wind turbines convert the wind kinetic energy into electrical energy through the blades that rotate thanks to the force of the wind. These blades can rotate between 13 and 20 revolutions per minute (rpm), depending on the wind turbine technology and the wind speed at any given time. The blade materials also influence the rotation speed; lighter blades tend to spin faster.
The faster the blades go, the greater the amount of energy generated by the wind turbine, which increases its efficiencyHowever, in order to start the device in the first place, auxiliary power is needed. Once it is in operation, the wind becomes the only driver for the blades to rotate.
One of the highlights of wind turbines is their Long useful life, which exceeds 25 years. Although the installation costs and initial outlay can be high, the long operating time allows the investment to be amortized and generates economic benefits. In addition, as it is a clean energy, they contribute to the reduction of polluting emissions and the reduction of the use of fossil fuels.
Advances in technology have not only increased the useful life of wind turbines, but also made them more efficient, facilitating their installation in more optimal locations to maximize the capture of wind energy.
Operation
The energy transformation process in a wind turbine takes place in several phases, each of them key to converting wind energy into electricity:
- Automatic orientation: The wind turbine automatically orients itself to make the most of the wind energy. This is made possible by the data recorded by the wind vane and the anemometer, which allow the nacelle to turn in the correct direction.
- Blade rotation: When the wind reaches a speed of approximately 3,5 m/s, it starts to spin the blades. To optimise power generation, the ideal wind speed is 11 m/s. If this speed exceeds 25 m/s, the blades are placed in a feathered position to avoid excessive stress and slow down the system.
- Multiplication: The rotation of the rotor drives a slow shaft that increases its speed from 13 rpm to about 1.500 rpm by means of a multiplier.
- Generation: The rotational energy is transferred to the generator, where it is transformed into electricity.
- Evacuation: The electricity generated is transported through the tower to the substation, where its voltage is raised before being injected into the electrical grid for distribution to the points of consumption.
- Monitoring: This process ensures that the wind turbine operates correctly. Critical systems are permanently monitored from the substation and the control centre, allowing possible incidents to be detected and resolved quickly.
Types of wind turbines
There are two main categories of wind turbines, which are classified according to the rotor axis or the power they can supply.
According to the rotor axis
Vertical axis
This type of wind turbine is omnidirectional and does not require orientation systems, which makes its installation and maintenance easier. In addition, its components such as the generator and the gearbox are at ground level, which simplifies its construction and reduces costs. However, its main disadvantage is that have lower efficiency than those with a horizontal axis and require external systems to start the rotation of the blades.
Horizontal axis
The wind turbines horizontal axis They are the most common and efficient. Their design allows for higher rotation speeds and therefore requires less speed multiplication. Furthermore, as they are taller, they are able to better harness wind energy at high altitudes.
According to the power supplied
In function of the power suppliedWind turbines are divided into three classes:
- Low power: They offer powers of up to 50 kW and are used in applications such as pumping water or supplying power in isolated areas.
- Half power: They are in the range of 150 kW and are used to supply power to the grid in rural or isolated locations.
- High power: They provide energy on a commercial scale and their production can reach up to several gigawatts.
Today, high-power equipment is the most widely used in wind farms to produce electricity efficiently and economically, contributing to the fight against climate change.
The renewable energy sector continues to evolve, driven by the need to reduce greenhouse gas emissions and mitigate the impact of climate change. Wind turbines, in particular, have seen significant technological advances, allowing them to generate more electricity and have a longer lifespan. With this information, you will better understand how wind turbines work and their key role in the future of clean energy.