Story: Hydroelectricity

Hydro-generation machinery

The energy of water moving at high pressure gets turned into electricity using whirling magnets and copper wire. The magnets are arranged in a circle (the rotor), which spins inside a circle of coils of copper wire (the stator). As the magnetic field passes through the coiled copper, it generates an electrical current in the wires. The spinning action is driven by water passing through a kind of waterwheel (the turbine). If the water pressure is greater – because the water is falling further – then more electricity will be generated.

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How to cite this page:

John E. Martin, 'Hydroelectricity - Hydroelectricity development', Te Ara - the Encyclopedia of New Zealand, (accessed 21 May 2022)

Story by John E. Martin, published 11 Mar 2010