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Electrical power

Electrical power

Big Bend Power Station, Tampa Bay, FloridaBig Bend Power Station, Tampa Bay, Florida Electricity is a type of energy that gives us heat and light and drives machines. To be useful, electricity must be made to flow in a current. In 1831 the British scientist Michael Faraday used a magnet to produce electricity. He moved a loop of wire over the magnet, causing an electric current to flow along the wire. This principle is used to generate electricity in power stations today.

 Cross-section through a generator inside a power... Cross-section through a generator inside a power...


Generators provide nearly all of the power for electric power grids. A generator makes electricity by converting motion (kinetic energy) into electrical energy. It does so by using the principle of electromagnetism: a magnetic field moving near a wire causes electricity to flow along the wire. In a generator, an electromagnet (the rotor) rotates inside an electric coil (the stator). The effect induces (creates) an electric current when it is connected to a circuit.

Diagram of a coal-fired power stationDiagram of a coal-fired power station


The world's first power station was built in the German town of Ettal in 1878. The station consisted of 24 electric generators, driven by a steam engine.

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