It takes a lot of energy to deliver safe water, remove and treat sewage, and manage drainage and waterways across Melbourne. See how we're generating renewable energy from treating sewage and from hydroelectric power stations - and how we're working toward net zero carbon emissions.
Biogas: converting sewage into 'poo power'
Sewage is much more than a waste product. We generate electricity by combusting biogas, which is captured under covers that are placed over our sewage treatment lagoons.
Melbourne Water’s water supply network is generating more electricity than it uses. We generate electricity from treating sewage and from hydroelectric power stations.
Western Treatment Plant
The Western Treatment Plant uses biogas to meet nearly all of its electricity needs. It generates 71,500 megawatt hours of renewable electricity every year, which prevents 87,000 tonnes of carbon dioxide from being emitted through the burning of fossil fuels.
Sometimes the plant produces more energy than it uses. Excess electricity is exported to the electricity grid to offset usage at our other sites.
Eastern Treatment Plant
The Eastern Treatment Plant uses biogas to power a substantial part of its electricity usage, and most of its heating and cooling. The plant’s seven generators can run solely on biogas or be supplemented by natural gas as needed.
Biosolids are the solid organic material left over after sewage treatment. These treated biosolids look and smell like soil, and contain beneficial nutrients like nitrogen, carbon and phosphorus.
Check out Biosolids for to learn more about how they're made, and how they're used for agriculture, composting and resource recovery.
Thermal processing technology
Melbourne’s forecast population growth means we need to think about how to enhance our sewage treatment capacity, at the same time as continuing to provide cost-effective services. We are exploring options, including thermal processing, for more efficient treatment of biosolids at the Eastern Treatment Plant.
We have 14 hydroelectric power stations installed in our water supply network, which generate up to 69,500 megawatt hours of electricity each year. These power stations generate energy from the flow and pressure of moving water, and feed it back into the electricity grid.
By operating these power stations, we can offset the equivalent of 75,800 tonnes of carbon dioxide emissions each year – equivalent to the emissions of over 14,000 homes.
Improving our energy efficiency
Energy use is one of our biggest sources of greenhouse gas emissions. Finding opportunities to improve energy efficiency will reduce our energy consumption.
We’ve already made many improvements to our operations, with:
- over 95% of our electricity use audited
- plant energy baselines established via improved monitoring
- over 100 energy efficiency opportunities identified
- annual energy savings of over $1.4 million identified, with more than $700,000 in total potential savings implemented.
Did you know the Australian Government’s Energy Efficiency Opportunities program encourages large energy-using businesses to improve their energy efficiency?
Melbourne Water is required to participate in the Energy Efficiency Opportunities program as we use more than 0.5 petajoules of energy each year – equal to 139 gigawatt hours, 21,500 tonnes of black coal or 15 million litres of petrol. This requires us to identify, evaluate and publicly report on cost-effective energy-saving opportunities.
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Working toward net zero carbon emissions
Find out how what other improvements are under way, and how we're working toward net zero carbon emissions.