Malabar: the first biomethane injected into a gas grid in Australia

In June 2023 the first biomethane in Australia produced from sewage biogas entered the gas network of New South Wales. The project at the Malabar treatment plant in Sydney, carried out jointly by the network operator Jemena and the water utility Sydney Water with the support of the agency ARENA, began injecting renewable gas into the existing distribution system.

How the plant works

The biogas is produced in the digesters of the Malabar treatment plant, where sewage sludge is stabilised anaerobically. According to Jemena, contaminants and impurities are removed from the raw biogas, and the cleaned biomethane goes into the Jemena distribution network. An earlier ARENA announcement from 2020 described this as the use of gas cleaning and upgrading equipment at the treatment plant.

Scale and costs

Initial production is about 95 TJ a year, which according to Bioenergy Australia corresponds to the annual consumption of about 6,300 households. The parties concluded a long-term agreement that provides for increasing the volume to about 200 TJ a year (ARENA links this value with the demand of about 13,300 households). ARENA estimated the project cost in 2020 at 14 million Australian dollars, of which 5.9 million AUD came from ARENA funding for Jemena; later reports from the start of construction mentioned a higher amount (about 16 million AUD).

Off-taker and certification

The biomethane is bought by Origin Energy under an agreement with Jemena. The project was the first to be assessed under the pilot renewable gas accreditation scheme run as part of the GreenPower programme. This matters because without a credible certification system customers cannot verify that the gas they are buying is renewable.

Delays

Earlier ARENA and Sydney Water announcements foresaw commissioning in 2022. Actual injection took place a year later, which is an example of the typical delays of a country's first projects with new technical and regulatory requirements for gas quality.

Significance

Malabar is the first proof that biomethane can be injected into a distribution network in Australia. Further projects, described among others in industry reports, require matched policies: certificates of origin, gas quality standards and charging models. For the water sector this means a new option for managing biogas, traditionally burned in engines or flared.

What this means for Poland

Polish wastewater treatment plants also have biogas, most of which goes to cogeneration. Malabar shows an alternative: biomethane from a treatment plant as a product for the grid. In Poland the role of “accreditation” is played by guarantees of origin, and the barriers are charges and connection conditions.