How do wind turbines work?
One of the most popular questions we get here at Good Energy is how is our renewable electricity generated. The simple answer is through wind, sun and rain – but this doesn’t really paint the whole picture.
How does the raw power – wind, sunshine and water – create electricity? Here’s (almost) everything that you need to know about generating electricity from the wind.
How do wind turbines work?
When wind blows, it carries kinetic energy which can move objects. A wind turbine has blades which are designed to rotate when hit by the wind – this motion is vital to the generation of electricity.
Most wind turbines start operating at a wind speed of 3-5 meters per second which is a gentle breeze; as the blades of the turbine spin they turn a shaft in the nacelle, or the box on top of a wind turbine.
A generator, which is built into the nacelle, then converts this rotational energy into electrical energy which then needs to be transformed into a suitable voltage to be connected to the grid or used by a local site.
Regardless of the size or location of a wind turbine, they all use the same mechanics in order to generate electricity.
How much electricity can a wind turbine create?
This is largely dependent on wind speed and the type of turbine being used. Most onshore wind turbines have a capacity of 2-3MW (but they can be as large as 9MW!) which can produce in excess of 6 million kWh every year – that’s enough to supply around 1,500 average households with electricity.
To get the most electricity from a wind turbine, it needs to be ideally positioned for optimum wind. The best sites tend to be on the summit of a hilltop with lots of open space around it to help prevent there being any disruption to the wind.
Up to a certain level, the faster the wind blows, the more electricity is generated – turbines self-regulate to prevent damage. In fact, when wind speed is doubled the production of electricity goes up eightfold.
How efficient is wind power?
Some people claim that wind turbines are inefficient, but that’s not necessarily true. A wind turbine is typically 30-45% efficient and can even be 50% efficient at peak times! If this sounds low to you, then consider that if these turbines were 100% efficient then wind would stop dead after going through the turbines.
In addition to this, wind turbines produce electricity around 70-80% of the time making them an excellent source of power throughout the year.
Why is wind power essential in the UK?
The UK is an especially windy place, with Scotland being the windiest place in Europe!
But what’s really good about wind is that it blows all year round and it gets especially gusty in winter – which happens to be when we use the most energy.
We’re well positioned to make the most of onshore wind power in the UK, which puts it in good stead to help reduce the UK’s dependence on fossil fuels. Another added bonus is the low carbon footprint that is created in building wind farms – it’s one of the smallest amongst new renewable generators.
What percentage of the UK’s electricity comes from wind power?
Every year wind power contributes more and more to the total percentage of electricity being used in the UK. In 2016 this figure stood at 11.5% thanks to the UK having a total generation capacity of over 14.4 gigawatts of wind power. This means that wind turbines can produce 38,574,800 MWh every year!
Considering that in 2013 this figure sat at just 7.39% the UK really has come on in leaps and bounds in just a few years.
How many wind turbines are there in the UK?
As of January 2017, there are 5,730 onshore wind turbines and 1,465 offshore turbines in the UK; these have a total operational capacity of 9,387MW and 5097MW of electricity, respectively.
At Good Energy we have two wind farms with another in the early stages of planning - this is a truly exciting project, set to be the UK's first subsidy free community owned wind farm. In addition to this, we work with hundreds of independent generators across the country to deliver renewable electricity to our customers.