An increasing number large-scale – or ‘utility’ – renewable power assets are being built, spurred by their declining cost. This increase in utility renewables is being mirrored by a rapid uptake in rooftop solar.
AGL’s hydro assets generate electricity to meet peak customer demand, and its ability to respond to rapid changes in demand is extremely valuable. While hydro only represents approximately 2.6% of the total electricity we generated in FY19, its ability to rapidly respond is what’s crucial during peak demand.
Hydro provides ‘firming capacity’ to the energy mix. Firming capacity is flexible energy supply that can be activated to top-up supply when the sun isn’t shining or the wind isn’t blowing, or there is a sudden concentration in demand.
Hydro at a glance
How does hydro work?
Hydroelectricity harnesses the power of flowing water and uses it to create electricity. The water turns a turbine as it falls through, which drives a generator, producing electricity. In many cases, the water sources are dammed to create a reservoir, which allows further control over the output of the hydro station.
A pumped hydro plant works much like a conventional hydroelectric station, except that the turbine can also act as a pump, moving water back uphill. During times of low electricity prices such as the middle of the day when the sun is shining or times of low electricity demand, such as at night or on weekends, cheap electricity is used to pump water to an upper reservoir.
During periods of higher demand or when network services are required water is released from the upper reservoir to generate electricity. The same water can be used over and over again.
AGL’s hydroelectricity portfolio
AGL Hydro’s three primary hydro schemes are in the Kiewa, Dartmouth and Eildon catchments in Victoria, with minor schemes located across New South Wales and elsewhere in Victoria.
Additionally, we are currently undertaking feasibility studies on two 250 MW pumped hydro schemes, in Kanmantoo in South Australia, and Bells Mountain in New South Wales.
Each of our generating schemes are located on different river catchments, maximising operational flexibility. Control of all generating plants is done from a central facility at AGL’s Bourke Street office in Melbourne, enabling us to rapidly respond to changing demand.
Below is a snapshot of AGL’s hydro assets.
|AGL's main hydro schemes||Total capacity||Average annual output|
|Kiewa Scheme2 (VIC)||392 MW||404 GWh|
|Dartmouth Power Station (VIC)||185 MW||217 GWh|
|Eildon Power Station (VIC)||120 MW||184 GWh|
2 The Kiewa Scheme comprises McKay Creek, Bogong, Clover, and West Kiewa Power Stations
|AGL's minor hydro schemes||Total capacity||Average annual output|
|Copeton Power Station (NSW)||22.5 MW||35 GWh|
|The Rubicon Scheme (VIC)||13.5 MW||64 GWh|
|Banimboola Power Station (VIC)||12.2 MW||11 GWh|
|Yarrowonga Power Station (VIC)||9.5 MW||50 GWh|
|Pindari Power Station (NSW)||5.7 MW||41 GWh|
|Burrendong Power Station (NSW)||19 MW||41 GWh|
|Glenbawn Power Station (NSW)||5.5 MW||12 GWh|
|Cairn Curran Power Station (VIC)||2 MW||2 GWh|
|AGL's proposed pumped hydro schemes||Total capacity||Potential completion|
|Kanmantoo Pumped Hydro1 (SA)||250 MW||FY25|
|Bells Mountain Pumped Hydro1 (NSW)||250 MW||FY26|
1 Both the Kanmantoo and Bells Mountain Pumped Hydro projects are currently undergoing feasibility studies
Update: in February 2020, AGL and Hillgrove Resources Limited, which owns the Kanmantoo site, mutually agreed to not continue with the proposed pumped hydro project. However, AGL remains committed to continuing the development of energy storage projects such as batteries and pumped hydro to providing firming capacity to the market.
These projects include a 100 MW battery in Wandoan, Queensland, a 30 MW battery in South Australia, and four 50 MW batteries to be built in NSW. We are also investigating the feasibility of a 250 MW pumped hydro plant at Bells Mountain in NSW, and a 50 MW battery at Broken Hill.