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Tell me more about how generators work!
Have you read the What exactly is electricity? page? On this page, we’ll look at how electricity is generated. We will look at how to generate electricity that always flows in a fixed direction with a constant force. As we saw on the previous page, this type of electricity is useful for us. In 1831, an English scientist named Michael Faraday discovered the principle that makes electricity.

The picture shows a metal wire wound around and around to form a coil. Faraday discovered that when he inserted a magnet inside the coil, the free electrons inside the metal wire would start to flow in a fixed direction. This was caused by the magnetic force of the magnet. The faster the magnet moves through the coil, the stronger the flow of free electrons and the stronger the electricity. The problem was it was very hard to move the magnet through the coil again and again at a high speed. So what do you think the solution was?

What about turning the coil rather than moving the magnet? When Faraday tried this, he found electricity was generated just like before. Turning the coil is much easier! But is there an even better way to make electricity? People around the world are always trying to answer this question by running many experiments. Because of these experiments, people have created many useful devices. Today, most large power generators produce electricity by spinning a coil inside a magnet. For example, think about a hydroelectric power station at a dam that you might see in the mountains. The dam partially blocks a river to raise the water level. When the water falls from the top of the dam, its force turns a special water wheel called a turbine. The turbine then spins the coil. That is how a hydroelectric power station works. At a thermal power station, coal or other fuels are burned to boil water. The force of the steam rising up from the boiling water turns a turbine. These days, you can often see wind turbines on cliffs and mountains. When their big blades turn, they also turn coils to generate electricity. In short, as long as you have a force to turn a coil, then you can generate electricity by nearly any means.