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 23.3 per cent of total clean energy generated and 6.4 per cent of Australia’s overall electricity in 2020. 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 2020
of total electricity generated in 2020
After losing its crown as Australia's leading renewable energy generator in 2019, hydro slipped to third place in 2020 as generation from the booming rooftop solar sector overtook hydro for the first time. This came despite hydro generation increasing by 473 GWh in 2020 to 14,638 GWh, its highest level since 2018.
However, while the technology's share of renewable energy generation may have shrunk in recent years, its importance to the industry's future is growing with each new megawatt of solar and wind capacity that is installed. This is because of the critical role that hydro will play in firming Australia's substantial wind and solar resources, with a number of major hydro projects under development that will enable further expansion of renewable energy in Australia.
The biggest new hydro project is Snowy 2.0, a 2000 MW/350,000 MWh project currently under construction in New South Wales. The project reached a number of significant development milestones in 2020, including state and federal environmental approval, which were both fast-tracked as part of the governments' COVID-19 recovery efforts, a $125 million transmission investment by the Clean Energy Finance Corporation and approval of a segment factory, which will manufacture 130,000 concrete tunnel segments for use during construction of the project.
Tasmania's Battery of the Nation project also continued to progress in 2020, with Hydro Tasmania naming Lake Cethana in north-west Tasmania as its first pumped hydro site for the project. Marinus Link, a second interconnector connecting Tasmania to the mainland that is a critical component of the Battery of the Nation project, also took a step closer to realisation after the Federal Government committed $94 million to take the project to the final investment decision stage.
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.
jobs created during the lifetime of Snowy 2.05000
The future of hydro also looks bright in New South Wales after the state government committed $50 million in grants to support the delivery of pumped hydro projects in the state as part of its Electricity Infrastructure Roadmap, the proposed Oven Mountain pumped hydro project was deemed as Critical State Significant Infrastructure by the state government and GE signed an agreement with Walcha Energy to develop a 500 MW pumped hydro project at Dungowan Dam.