How Does a Wind Turbine Work?

Someone once likened them to airplane propellers that run on the spot and we totally agree – turbines simply spin around but never go anywhere.

However, they serve a great purpose in that they provide a renewable source of clean energy. The rotors do a great job of capturing some of the energy in wind and converting it to electricity.

On that note, how does a wind turbine work?

This is a common question, especially among individuals looking to live off the grid. The simple answer is through the rain, wind and sun – but it’s there is more to it.

In this post, we tackle everything about how wind turbines generate electricity.

How Wind Turbines Work

When hit by wind, the rotor blades spin around and capture some kinetic energy from the moving air. This turns the central shaft supporting the rotors, which moves at a slower speed.

Most modern turbines utilize the pitch control mechanism to harvest optimal energy. This is where the rotor blades swivel on the front hub and meet the wind at a perfect angle.

The gearbox, located inside the body of the turbine and behind the blades, converts the slow speed of the central shaft to high speed rotations of up to 1600 rpm. This ensures the shaft is fast enough to drive the generator. The generator converts the kinetic energy from the shaft to electrical energy.

A 2MW generator running at maximum capacity can produce 2 million watts at 700 volts.

Wind turbines often come with a wind vane and anemometer for measuring wind direction and speed. Both are usually located at the back of the nacelle.

The yaw motor uses these measurements to determine how to turn the entire top of the turbine and harvest optimal energy. It also applies brakes to stop the rotors if the winds are too turbulent or during maintenance.

The electric current generated runs down to the transformer, which coverts it to 50x higher voltage for efficient transmission to the power grid. Homes can then enjoy clean energy whose production doesn’t result in carbon dioxide emissions.

What if the Wind Doesn’t Blow?

Renewable-Energy-Wind-Electricity-Generation

Because wind is such a variable source of energy, it stands to reason that some people worry about sudden blackout due to over-reliance.

The reality is very different. Utility companies use a complex network of interconnected power generating units to match the total power demand. These power generating units range from individual wind turbines to giant power plants.

While a 1000 turbines to produce as much power as a nuclear plant, failure of one turbine only causes 0.1% disruption. This is unlike nuclear plants, which may need to go offline for maintenance.

Wind can be predicted several days ahead, giving utility companies time to figure out a way to make enough power to meet expected demands.

Those opposed to wind as a source of power have cited counter-productivity. This is because there’d be need to build extra backup or store wind power for days when there are insufficient winds to produce energy.

This would only be a problem if all energy was produced from one giant turbine. But that’s not really how it works. Countries with large supplies of wind energy also have other power sources.

How Much Electricity Can Wind Turbines Generate?

Onshore turbines with a 2-3 megawatts capacity are capable of producing more than 6 million kWh of electricity each year. This can power over 1500 households.

Faster winds equate to increased energy production up to a certain point.

While double wind speeds can increase electricity production by up to eight times, too much wind can result in shutdown of the rotors.

This is to say that the amount of electricity generated depends on the strength of wind.

Types of Wind Turbines

Wind turbines are generally classified into two i.e. horizontal axis and vertical axis turbines. Let’s take a closer look at both, shall we?!

Horizontal Axis Wind Turbines: These can either be downward or upward turbines depending on how the blades are attached to the tower structure. Downward turbines are less efficient than upward turbines due to turbulence of the tower. Upward turbines often face the wind, thus improving efficiency.
Vertical Axis Wind Turbines: They are more efficient than horizontal axis turbines. This is because they work regardless of the wind direction. There are different types including eggbeater turbines, which use airplane wing-like blades running in a horizontal direction. Savonius turbines use cup-shaped blades to capture the wind.

Advantages and Disadvantages of Wind Turbines

Pros

Zero water and air pollution
Minimal carbon dioxide emissions and none after construction is completed
Unlike fossils, wind never runs hence a sustainable source of energy
Operating costs can be predicted years in advance
Job creation in construction, manufacture and operation of wind turbines
Turbines work almost anywhere in the world since all they need is reliable wind speeds
Not affected by political volatility or fluctuating energy prices

Cons

Upfront costs are incredibly high
Upgrading power and transmission lines is costly
Incapable of supplying an entire country with reliable power like hydroelectric, biomass and fossil fuels
Variable output due to seasonal changes in wind speeds
Economic subsidies are needed to make wind a viable energy source

Conclusion

Wind turbines are pretty complex machines made of many parts. This guide may be short and concise, but we certainly hope you now understand how turbines work.

Hopefully, you know the different turbines, how they produce electricity and what affects production. We’ve also included a section on the benefits and drawbacks of wind power.

There is no better time to implement more sustainable forms of energy than now, and understanding how turbines work is a step in the right direction. While they produce more energy, fossil fuels are desolate and non-sustainable forms of energy.

Wind power is sustainable and ensures the continued survival of the planet. Raising awareness about its benefits can only be successful if we ourselves are knowledgeable.