Biomethane being injected into Sydney gas system

Renewable biomethane is being injected into Sydney’s gas distribution system following the completion of an upgrade to Sydney Water’s Malabar Wastewater Treatment Plant.

The eastern suburbs facility has seen gas distributor Jemena’s Malabar Biomethane Injection Plant producing biomethane from waste and added to its gas distribution network.

The plant previously processed organic material in wastewater to produce biogas which was burnt to generate electricity and heat, or was flared off.

Biogas is a flammable but low grade mixture of gases and methane produced during anaerobic digestion by bacteria.

Sources of organic matter range from animal manure, municipal waste and food waste through to processed wastewater and sewage sludge.

Alternatively, a process called upgrading can convert the biogas to near pure biomethane.

Utilising the process at Malabar in a project supported by the Australian Renewable Energy Agency (ARENA) removes the CO2, water vapour and trace gases to leave almost pure – 98 per cent – biomethane.

Biomethane is both chemically identical to fossil-fuel derived methane and suitable for injection into existing natural gas networks.

But, because it is produced from organic waste, it is potentially a net zero emissions energy source.

Jemena Managing Director Frank Tudor said biomethane was a ‘here-and-now’ pathway for Australia to reduce emissions.

Tudor said: “Our Malabar Biomethane Injection Plant is turning what Sydney-siders flush away into an energy source that can be used in the same way as natural gas in manufacturing processes and heating and cooking appliances.”

Jemena said its research found that in New South Wales alone, there are enough potential sources of biomethane to meet the needs of around a third of Jemena’s current NSW customers.

ARENA provided $5.9 million to support the Australian-first project.

Picture: ARENA