In an Australian-first, Sydneysiders can help make biomethane with a simple flush of the loo.
Biomethane produced using wastewater is being injected directly into the NSW gas distribution network from a demonstration plant in Sydney's south-east.
The Malabar plant will initially produce around 95 terajoules of the "renewable gas" each year, which is equivalent to the average yearly use of 6300 homes.
Sydney Water boss Roch Cheroux said the utility was responding to the changing needs of households and businesses who wanted to increase their efficiency and sustainability.
"From this moment, gas will be directed back into the supply network, allowing the facility to turn waste material into a new renewable energy source," he said.
"For the first time, it will be possible to use a mix of biomethane and natural gas for cooking, heating, and hot water."
Co-funded by energy infrastructure company Jemena and the Australian Renewable Energy Agency, the plant produces the alternative gas in two stages.
First, biogas is produced through "anaerobic digestion", where bacteria breaks down organic matter in the wastewater. Then contaminants and impurities are removed.
The state has enough potential sources of biomethane - wastewater plants, landfill and food, agricultural, and crop waste - to generate about 30 petajoules of biomethane each year, according to Jemena.
That would be enough gas to meet the needs of all of Jemena's residential customers in NSW.
“This is a potential game-changer for Australian energy users," managing director Frank Tudor said.
"Biomethane is completely compatible with existing gas appliances and can be used in those manufacturing processes which currently rely on gas for heat."
Origin Energy has signed an agreement with Jemena for the biomethane produced at Malabar and will offer it to business customers.
