When it comes to generating electricity, one of the UK’s most abundant renewable sources is wind. This invisible clean energy source has been used for centuries in the form of windmills.

Nowadays wind turbines convert the power of the wind into the electricity that we use in our homes and businesses. They can be stand-alone for local use or clustered to form part of a wind farm helping to power the National Grid.

Here we take a look at how they work, how much energy a turbine produces, and how important they are to our energy future.

How do wind turbines work?

Those towering wind turbines you can spot around the country usually consist of a set of propeller-like blades, a box on the back called a nacelle (which contains a generator), and a shaft.

Wind turns the blades of the turbine – and this doesn’t have to be a strong wind either. In fact, the blades of most turbines will start turning at a speed of 3-5 metres per second, which is a gentle breeze.

As the blades rotate they turn a central shaft, a gearbox then shifts these rotations to a speed high enough to spin a generator inside the nacelle, which creates electricity.

The electricity generated enters the National Grid via a transformer on site that increases the voltage. This is so the energy can travel efficiently through the national electricity network, before eventually reaching homes and businesses.

How much energy does a wind turbine produce?

Most onshore wind turbines have a capacity of 2-3 megawatts (MW), which can produce 6 million kilowatt hours (kWh) of electricity every year. Enough to power around 1,500 average households with electricity.

As the wind blows faster, more electricity is generated. In fact, when the wind speed doubles, the electricity created can be up to eight times more.

The turbines generate around 80% of the time, but not always at full capacity. During powerful storms, with very high wind speeds they are shut down to prevent damage.

To generate the maximum amount of power, wind turbines depend on having reliable amounts of wind all year round. This tends to be on hilltops surrounded by open space, or in coastal locations. Hence why there are quite a lot of wind farms in places like Scotland and Cornwall.

13 MW wind turbines and the world’s biggest wind farm.

Over the past few years, General Electric (GE) has been developing the ‘Haliade-X’ – the world’s most powerful offshore wind turbine.

Just one rotation of a GE Haliade-X 13 MW, which stands at a total height of 260 metres (853 ft), could power a UK household for more than two days.

These giant turbines are going to be part of the world’s largest offshore wind farm at Dogger Bank, located 130km off the North East coast of England. The wind farm is expected to deliver its first electricity in 2023, and when completed it will be capable of powering 6 million British homes.

Why are there so many wind turbines in the UK?

The UK’s unique exposed location makes it particularly windy, with Scotland being the windiest place in the whole of Europe. So more wind naturally means more wind turbines.

Also, because the wind blows all year round, it makes wind turbines in the UK a reliable renewable power source. An added bonus is that it tends to be windiest in winter when we as a nation use most electricity.

Wind turbine numbers are rising.

There are over 8,800 onshore wind turbines and over 2,600 offshore turbines in the UK. Altogether, they produce enough power to meet the annual electricity demand of around 18 million homes. You can find the latest statistics on wind farms at RenewableUK.

How much UK electricity comes from wind power?

In 2020, around 24% of the UK’s electricity was generated from wind power*. Just seven years before, this percentage was just over 7%. This demonstrates just how fast wind power capacity in the UK is growing.

Wind turbines are an increasingly important source of intermittent renewable energy and can be used to lower energy costs and reduce reliance on fossil fuels. Wind power is also a big part of the UK plan to reach net zero government targets by 2030.

To see how much UK power is being generated by wind you can download the National Grid ESO app from Google Play or Apple iOS.

Feel the Community power.

The E.ON Next Community is a space for customers just like you, sharing their experiences to offer a helping hand. Find support or suggest your own unique topics, plus get involved in discussions of all the latest news. Join the conversation now.

*https://www.ons.gov.uk/economy/environmentalaccounts/articles/windenergyintheuk/june2021

Blog published: 19/12/22