Wind turbines use energy from the wind to provide mechanical and electrical power.
In MegaWatt, the wind technology card is a low cost and low environmental impact option. Its weakness is a low power capacity due to variable wind and high land use.
Over the last two decades, wind farms have dropped in cost a lot! Wind turbines also have no emissions when spinning, although like every other technology they do need resources to build (like rare earth elements for the magnets in some turbines). A trade-off is that wind doesn't have the highest power capacity of the technology cards; when the wind conditions aren't right the turbines can't provide electrical power, and it's not possible to control the wind. Wind farms are also not very power dense when compared to options like nuclear or coal, which means that they need much larger areas of land (or sea) to provide a similar amount of power.
Now for some stats from the UK grid in 2019.
Renewables provided around 37% of the electricity generation (121 TWh), which is 4% more than the year before. Most of this increase was from onshore and offshore wind, providing 32 TWh each.
When all of the wind farms in the UK are lumped together, and the numbers adjusted to account for turbines not spinning as fast as they can all of the time (with a number called the capacity factor), there's a de-rated power capacity of around 10,000 MW. That's over 13% of the UK total, and it will keep growing. The government recently announced a new target of 40,000 MW of installed offshore wind capacity by 2030.
Advances in wind technology have seen turbines move offshore, becoming much bigger and operating in deeper waters. In the future, we'll even see floating wind turbines which could take advantage of better wind conditions and less planning restrictions further from the coast. Check out this video about offshore wind in the UK!
If you want to learn more, here are some examples of wind farms around the world.
In Scotland, Whitelee Wind Farm has 215 turbines with an installed capacity of 539 MW. This is the maximum amount of power the wind farm can make when the wind conditions are in the right range and when the grid can accept the power.
On the other side of the world in China, Gansu Wind Farm will eventually have around 7,000 turbines and an installed capacity of 20 GW. That's about 37 times bigger than Whitelee!
Meanwhile, back in the UK, the world's largest offshore wind farm will soon be built in the North Sea. The Dogger Bank Wind Farm will have an installed capacity of 3.6 GW across its three sites.
All of the numbers we used for the UK statistics can be found in the Digest of United Kingdom Energy Statistics 2020 which is from the Department for Business, Energy & Industrial Strategy (the people in government who look after our energy policy). The 2019 UK grid capacity is based on the de-rated capacity, which includes a capacity factor to adjust the value for comparison to firm power sources.