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Did you know that wind is considered an indirect form of solar energy?
Why? - because the wind is driven mainly by temperature differences on the surface of the earth caused by sunshine.
What did we use wind power for in the past?
Now, people use the wind to generate electricity. The windmills built long ago had many blades, but today's wind turbines usually have just two or three blades that turn when the wind blows. But the blades on electric wind turbines are much longer than those you might see on a windmill. In fact, wind turbine blades can be up to 25 metres long!
Wind turbines can produce electricity whenever the wind blows (at night and during the day). In theory, wind systems can produce electricity 24 hours every day.
The blades drive a generator that produces electricity. The longer the blades and the faster the wind speed, the more electricity the turbine generates. Wind turbines are placed on towers because the wind blows harder and more steadily above the ground.
To produce the most electricity, wind turbines need to be located in areas where the wind blows at a constant speed, which it does not do in all parts of the world.
Large groups of wind turbines, called wind farms, are connected to electric utility power lines and provide electricity to many people.
One of Scotland's twelve wind farms is at Deucheran Hill. Electricity generated by the turbines is transmitted through overhead powerlines to a substation at Carradale, from where the power is distributed to Scottish people. The annual output from the wind farm will be equivalent to the electricity consumption of 13,000 households and eliminates the release of 23,000 tonnes of carbon dioxide into the atmosphere each year.
Another wind farm called Beinn Ghlas is located south of Taynuilt, near Oban. The wind farm consists of 14 wind turbines. One of the turbines is named 'Jessica' after a local schoolgirl who wrote to the company that made them describing the turbines as angels.
However, even in the windiest places, the wind does not blow all the time and we're still learning about local wind patterns and how they affect wind turbines and blades.
