Hydroelectricity (also known as 'hydro') is a well-developed renewable energy technology that has been around for more than a century.
Hydro uses flowing water to spin a turbine connected to a generator that produces electricity. The amount of electricity generated depends on the volume of water and the height of the water above the turbine.
Large hydroelectric power stations need dams to store the water required to produce electricity. These dams are often built to hold irrigation or drinking water, and the power station is included in the project to ensure maximum value is extracted from the water.
Hydroelectricity does not actually consume any water, as all the water is returned to the river after use.
While hydro plants can have very large capacities, the amount of electricity they generate can vary markedly from year to year depending on rainfall and electricity demand. Hydro can provide both baseload and peakload electricity, and hydro generators can start up and supply maximum power within 90 seconds.
Smaller hydroelectric power stations (called mini or micro hydro) do not generally need dams but rely on naturally flowing water such as streams. These provide a good source of power and are often used as stand-alone systems not connected to the main electricity grid.
Hydroelectricity in Australia: 2015 in focus
Hydro power currently accounts for 40.1 per cent of the renewable electricity produced in Australia. The majority of this energy is generated by Tasmania's hydroelectric plants and the Snowy River Hydro Scheme in New South Wales.
The amount of hydro power generated in 2015 was lower than 2014 due to low rainfall in key hydro catchments. Hydro Tasmania’s network endured the driest period on record between September and November, and storages dropped to a quarter of capacity (25.7 per cent).
Top five hydro plants in Australia – by generation (as at end of 2015)
|Upper Tumu||Snowy Hydro||NSW||1039|
The future of hydroelectricity in Australia
The majority of Australia's suitable hydro sites have already been developed, so the sector's opportunity for growth is limited. In coming years, most of the activity in the sector will be in developing mini hydro power plants or upgrading and refurbishing existing power stations.
- Clean Energy Council Renewable Database
- Clean Energy Australia Report 2015