Hydropower is one of the oldest and most mature energy technologies, and has been used in various forms for thousands of years.
According to the International Hydropower Association, more than 50% of the world’s renewable energy is powered by hydro plants, and in 2022 was responsible for 15% of all electrical generation on the planet.
There are over 120 operating hydroelectric power stations in Australia, large and small, mostly located in south eastern Australia. In Tasmania 80% of energy is generated by hydro power. There are also three major PHES systems connected to the national electricity grid.
In 2023, hydropower represented 6.5% of the total energy supply according to the Clean Energy Council. In total, hydro contributed more than 15.3 million MWh of power in that year.
Hydropower converts the energy of moving water into electricity.
There are four main kinds of hydro power:
Run-of-river
Storage
Pumped Hydro Energy Storage (PHES)
Offshore hydropower
Hydroelectricity is generated by channeling water—usually from a reservoir or dam—through a turbine, which acts as a powerful electricity generator. As the water rushes through the turbine's blades, it spins the generator, transforming that motion into clean electrical energy.
Pumped Hydro Energy Storage (PHES) takes this concept a step further, turning water reservoirs into massive energy banks. During times of low energy demand, surplus power from the grid or renewable sources like wind and solar can be used to pump water from a lower dam to a higher one. This creates a giant "battery" of stored energy, ready to be unleashed when demand peaks or renewable output dips.
What makes hydroelectricity so valuable is its ability to be generated instantly, whenever needed. This flexibility allows it to step in during surges, prevent blackouts, and meet sudden spikes in electricity demand. PHES, in particular, offers the advantage of producing large amounts of electricity over extended periods, providing a dependable and on-demand source of power.
Located at Lake Cressbrook, 64km south of Stanwell’s Tarong power stations and roughly 50km north-east of Toowoomba, the Cressbrook pumped hydro facility will generate 400 MW of clean energy for up to 10 hours when operational in 2033.
The project will use Lake Cressbrook as the lower reservoir with a new upper reservoir constructed on land, that will be owned by Stanwell and our project partner, 2.1km northeast of the lake.
During periods of high electricity demand or to firm the grid, up to 6.4GL of water would be released from the upper reservoir downstream into Lake Cressbrook, driving two 200 MW turbines for a period of up to 10 hours. Once this cycle is complete, the upper reservoir will be replenished with water pumped from Lake Cressbrook in readiness for the next release.
Cressbrook Media Release
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