How Do Wind Turbines Work?
How do wind turbines work? A wind turbine is like a fan, but works in an opposite way. Instead of using electricity to turn the fan, the fan turns and produces electricity.
Simply put, the wind turns the blades, which in turn spin a shaft. The shaft is connected to a generator that makes electricity. There are two kinds of wind turbines: horizontal axis and vertical axis.
Horizontal Axis Wind Turbines (HAWT) have two or three blades, and operate with the blades facing into the wind, or upwind. The blades are at an angle to create friction which causes the blades to turn. Advantages of horizontal axis wind turbines include:
- The angle of the blades can be remotely changed as needed
- They can be put on uneven land or offshore
- They can operate above the tree line
- They are cheaper because of larger sizes and are operated more efficiently
Disadvantages include: they have trouble operating near the ground, transporting them is difficult, and they have to be installed in shallow water off shore and can’t be floated on barges.
Vertical Axis Wind Turbines (VAWT) spin on a central point on the ground and have the rotator shaft running vertically. The Vertical Axis Wind Turbine doesn’t need to be pointed into the wind, but the winds at the surface are slower and more turbulent. Advantages include:
- Easier maintenance
- Wind speeds are stronger near the surface in some locations
- Easier to transport and install
- Don’t need a tower
Disadvantages include: They are not very efficient because of drag on the blades going into the wind, they need to be installed on flat land, and the have low starting torque.
History of Wind Turbines
Now that you know the answer to “How do wind turbines work?” you need to know a little of the history of wind turbines. The wind has been used for thousands of years. Five thousand years ago, boats on the Nile used wind energy to propel them. By 200 BC windmills in China pumped water, and in the Middle East they were grinding grain. Windmills were used around the world, especially for moving water from lakes or into homes. Windmills were also used to cut wood and generate electricity.
Today, there are wind power plants, or wind farms, that have dozens of wind turbines that produce electricity. The largest one is called the Horse Hollow Wind Energy Center and is located in Texas. It has 421 wind turbines that power 220,000 homes per year.
Alternative Energy
Since you know the answer to the question, “How do wind turbines work?” maybe you would like to know why there is so much interest in wind energy now. In the 1970s, there were oil shortages which made many people realize that fossil fuels will not last forever. Recent concern about global warming has made people more conscious of the need for cleaner and renewable resources. Wind is clean and free. Wind farms of wind turbines and windmills produce no pollution because no fuel is burned.
Today, an individual or business can purchase a small wind turbine. It is estimated that a small wind turbine will pay for itself within 5-10 years. At the home, they can be installed on the roof like a television antenna. The small wind turbines are used for homes, boats, refrigeration units, pumping water, and telecommunications dishes.
Solar energy is another energy source that is in plentiful supply and free. It is used to heat water in houses, swimming pools, and buildings, to heat houses, and to generate electricity.
Hydroelectricity is electricity generated by water. A dam is built and then the force of gravity pulls the water down and the power of that water is used to generate electricity. This is the most used form of renewable energy.