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 considerably from year to year depending on rainfall and electricity demand. Hydro can provide both baseload and peak load electricity, and hydro generators can start up and supply maximum power within 90 seconds.
Hydro power accounted for 35.2 per cent of total clean energy generated and 7.5 per cent of Australia’s overall electricity in 2018. There are more than 120 working hydro power stations in Australia, with most of the nation's hydroelectricity generated by Hydro Tasmania's network of power plants and the Snowy Mountains Hydro Scheme in New South Wales.
of total clean energy generated in 2018
of total electricity generated in 2018
Hydro had a strong year in 2018, with output over 3600 GWh higher than in 2017. Hydro remained the largest generator of renewable electricity in 2018, providing 35.2 per cent (17,002 GWh).
After two years of testing the project's financial and geotechnical feasibility, the Snowy Hydro board gave the official go-ahead for the 2000 MW Snowy 2.0 project to proceed in December 2018. In February 2019, the Federal Government announced that it would provide $1.38 billion to allow Snowy 2.0 to proceed. Upon completion, Snowy 2.0 will provide up to 2000 MW of additional capacity and 350,000 MWh of large-scale energy storage.
The Australian National University (ANU) has also identified 22,000 potential pumped hydro sites across Australia. So many good quality pumped hydro sites were identified that the ANU says that only the top 0.1 per cent of these would be needed to provide the necessary support for a 100 per cent renewable energy system in Australia.
potential pumped hydro sites across Australia22k
Tasmania's Battery of the Nation project also continues to inch closer to reality. In February 2019, Hydro Tasmania spent $30 million to take the first phase of the project to the investment stage and the Federal Government provided $56 million towards the construction of a second interconnector between Tasmania and the mainland, which is critical to the success of the pumped hydro project.
Snowy 2.0 and the Battery of the Nation clearly show that there is considerable desire in expanding the nation's hydro resources to provide additional storage capacity to complement renewable energy such as wind and solar power.