Hydroelectricity in Australia: Hydropower and Hydroelectric Generation
Hydropower (also known as just hydro) is one of the oldest methods of renewable energy generation. For thousands of years, water has been used to power mills to grind flour, break ore, and make paper. Since then, technology has greatly improved, and hydro has become an important renewable resource in the energy transition. By capturing the power of water, hydro energy can be turned into electricity for everyday use. To learn more about hydropower, and hydroelectricity in Australia, continue to read below.
What is hydropower? How does hydroelectricity work?
Hydropower is the power derived from the energy of falling or fast moving water. While traditionally this has been in the form of kinetic energy such as watermills, today the most popular use of hydropower is hydroelectric generation. By using dams and reservoirs in conjunction with turbines and generators, electricity can be generated and even stored for public use. As of 2020, over 60% of all global renewable energy was generated through hydropower.
There are four ways to generate electricity through hydro, which occasionally overlap in order to supplement electricity generation depending on the body of water that energy is being generated from.
Run-of-river hydropower utilizes the movement of water to generate electricity. Due to the nature of rivers, this method of hydropower often has no storage capacity and instead continuously generates a supply of electricity
Storage hydropower uses dams to store water in reservoirs, generating electricity by releasing the water through a turbine to activate the generators. Storage hydropower is able to meet demands of the electricity grid, by being able to turn off and on as needed and due to its storage capacity, can work for months without needing more water.
Pumped-storage hydropower is similar to storage hydropower, but requires the use of an upper and lower reservoir. When demand on the grid is high, water is released through turbines from the upper reservoir to the lower reservoir, and when demand is low water is pumped back into the upper reservoir using surplus energy.
Offshore hydropower is a newer method of hydroelectric generation, which utilizes tidal waves and tidal lagoons to generate electricity in a similar manner as hydroelectric dams.
The future of hydroelectricity in Australia
Hydropower was once the biggest source of renewable energy in Australia and nearly a decade ago, made up over 55% of the renewable energy generation in the country. However as the cost of other renewable energy technologies has decreased, and droughts caused by climate change have begun to dry up reservoirs, interest in hydro has been on the decline.
Clean Energy Council Reports 2013 - 2021
In 2019, hydro was the second largest renewable energy source in Australia, accounting for 25.7% of the country’s renewable energy generation portfolio. However a sudden spike in interest in small-scale solar has bumped hydropower to the third biggest renewable energy source (at 23.3%), putting it behind wind power (35.9%), and small-scale solar (23.5%).
Source: Clean Energy Council 2020 Report
That being said, there are over 100 hydro stations in Australia with more projects in the works. This includes Snowy Hydro which contributes to approximately half all hydroelectricity generated in the country and its latest project, Snowy 2.0, which is in the process of being built and will increase the hydroelectric capacity by an additional 2,000MW by 2025. Outside of Snowy Hydro, the network of hydroelectric generators in Tasmania (which heavily relies on the renewable resource), known as Hydro Tasmania, holds the largest concentration of hydropower.
While hydro might seem like it’s on the decline, the hydro industry was given a large financial boost in 2020. This includes its inclusion in the Federal Government’s Technology Investment Roadmap as one of five priority low-emissions technologies as well as additional funding from both the private and public sectors.
The pros and cons of hydroelectricity
Hydropower and hydroelectricity generation is among the most popular, and well known, renewable energy resources in the world. While hydropower does so much in the global energy transition, it isn’t without its disadvantages.
|Advantages of hydroelectricity||Disadvantages of hydroelectricity|
Advantages of hydropower
Hydropower is a renewable resource, as the water cycle is driven by the sun. It also pairs well with other renewable energies, such as solar and wind power, to ensure renewable energy is being generated 24/7.
Hydro can easily meet the needs of consumers, particularly when demand is high. Wind and solar energy can’t be used to generate electricity 24/7 but hydro can generate energy on demand by releasing the stored water through turbines. This also allows hydro to quickly provide essential power in the event of a blackout, as some types of hydropower stations can go from zero output to maximum output almost immediately.
Some types of hydropower plants that rely on reservoirs offer recreational opportunities for the residents in the surrounding areas such as for swimming, boating, and fishing.
Disadvantages of hydropower
Hydroelectric stations are usually massive, and the construction of hydroelectric stations around water sources can have a huge impact on the surrounding environment, particularly storage or pumped storage hydro which can interrupt the flow of the river and disrupt the animals that live and migrate around there.
The startup costs of hydropower are immensely expensive, as the infrastructure involved includes a dam, reservoir, and turbines, as well as needing to build the underwater foundations. It should be noted, however, that after the hydro station is built, it will require less maintenance.
Hydropower is dependent on rainfall and droughts, and with climate change affecting both, it’s getting harder and harder to not only find places to build hydro stations but the output of energy generated isn’t always remaining constant.
Micro-hydro energy generation and residential hydroelectricity
Micro-hydro power systems are small-scale systems (under 100KkW) that utilise small streams or rivers to generate power at a residential or community level. Micro-hydro systems are great, because they don’t require a lot of maintenance, and can run 24-hours a day without being dependent on wind or sun like solar power or wind energy.
Unfortunately, Australia is not well-suited for micro-hydro systems as continuously running water is required. However, if you have running water on your property, and wish to generate residential hydropower, micro-hydro systems can be more efficient and cost-effective as other small-scale renewable energy systems.