Wind turbines can turn the power of wind into the electricity we all use to power our homes and businesses. They can be stand-alone, supplying just one or a very small number of homes or businesses, or they can be clustered to form part of a wind farm. Here we explain how they work and why they are important to the future of energy.
A wind turbine is the very modern version of a windmill. Put simply, it uses the power of the wind to create electricity. Large wind turbines are the most visible, but you can also buy a small wind turbine for individual use, for example to provide power to a caravan or boat.
A wind farm is a group of wind turbines. It’s pretty impressive to think that the electricity that powers so much in our lives – from charging our phones, to allowing us to make a cup of coffee and, increasingly, fuelling our cars – might have started out as a simple gust of wind.
First let’s start with the visible parts of the wind farm that we’re all used to seeing – those towering white or pale grey turbines. Each of these turbines consists of a set of blades, a box beside them called a nacelle and a shaft. The wind – and this can be just a gentle breeze – makes the blades spin, creating kinetic energy. The blades rotating in this way then also make the shaft in the nacelle turn and a generator in the nacelle converts this kinetic energy into electrical energy.
To connect to the national grid, the electrical energy is then passed through a transformer on the site that increases the voltage to that used by the national electricity system. It’s at this stage that the electricity usually moves onto the National Grid transmission network, ready to then be passed on so that, eventually, it can be used in homes and businesses. Alternatively, a wind farm or a single wind turbine can generate electricity that is used privately by an individual or small set of homes or businesses.
Wind turbines do tend to be either white or very pale grey – the idea being to make them as visually unobtrusive as possible. There is discussion about whether they should be painted other colours, particularly green, in some settings to help them blend in with their environment better.
Wind turbines can operate in anything from very light to very strong wind speeds. They generate around 80% of the time, but not always at full capacity. In really high winds they shut down to prevent damage.
Wind farms tend to be located in the windiest places possible, to maximise the energy they can create – this is why you’ll be more likely to see them on hillsides or at the coast. Wind farms that are in the sea are called offshore wind farms, whereas those on dry land are termed onshore wind farms.
The very first wind turbine that produced electricity was created by Professor James Blyth at his holiday home in Scotland in 1887. It was 10m high and had a sail cloth.
The world’s first wind farm opened in New Hampshire in the US in 1980.