Hydroelectricity means electricity produced using energy in moving water.
How does it work:
Hydroelectricity plants are built on rivers in mountainous country and a dam has to be built to hold the water, which will drive the generator. The power station is located at the bottom of the dam wall.
To generate the electricity, water from the dam is released and driven downhill by gravity and several large pipes or tunnels. The water enters the power station and is directed into the turbine, which makes the blades spin, due to the force of the water. The shaft which is connected to the generator and driven by the turbine makes the generator’s magnets spin inside the coils of conductor and soon, electricity is produced. Depending on the water pressure striking the turbine’s blades and height which the water falls, determines the amount of electricity generated.


ü Good in remote areas
ü Can be installed in small rivers or streams with little or no bad environmental effects or disruption to fish migration
ü Most small scale hydro power stations make no use of dam or major water diversion
- But use water wheels to generate energy



Did you know?
15% of Australia's electricity needs is supplied from hydroelectric power.

The Snowy Mountains Hydroelectric Scheme is the largest engineering project ever built in Australia.It was built to generate electricity and provide water for irrigation. Although it began in 1949, it only finished in 1974. 145km of tunnels had been dug, 80km of aqueducts (channels to carry water) had been made, seven hydroelectric power stations were built and pumping stations were installed, two of them being underground.

Lake Eucumbene is the major reservoir of the scheme and holds 9 times the amount of water in Sydney. This project was considered one of the engineering wonders of the world.

How it works:
The Snowy Mountains catches the water that falls as rain or melts as snow and then directs it to the resrvoirs where the water is used to drive turbines to produce electricity. It flows downstream and used for irrigation in farmland along the Murray and Murrumbidgee Rivers. This hydroelectric plant is large enough to produce
up to 17% of south-eastern Australia's electricity supply, but has only enough water to generate 5%. The reason for having large generators is that so large amounts of electricty can be produced for short periods. If there is a shortage in south-eastern Australia, the water from the dams in the scheme can be released to produce enough electricity to meet the demand.