Over the past couple of months, there has been a lot of discussion about the way forward for Australia’s energy system.

Issues came to a head at the beginning of this winter with significant actions taken by the energy market operator, and commitments made by state and federal governments, to ensure Australians could keep their lights on and homes warm now and into the future.

Renewable gas is often overlooked in the net zero conversation. 

While there has been a focus on the role gas must play in our energy networks as we transition to net zero, there has not been much discussion about the huge potential for renewable or “green” gas and what role a decarbonised gas network could play.

It can be argued that in the puzzle of Australia’s future secure, stable, and sustainable energy system, renewable gas used in Australia’s existing gas infrastructure, is the often overlooked, yet critical, missing piece.

Australia’s network of gas infrastructure is extensive – some 39,000km spanning the country. It should be considered a valuable long-term asset in helping meet our emissions reduction targets as well as an important partner (providing firming power) to intermittent renewable generation such as wind and solar generation.

By decarbonising and repurposing existing infrastructure as opposed to building new, we can also help keep costs down for consumers. Conservative estimates indicate that continuing to use our current infrastructure for renewable gas will see consumers avoid about $12.5 billion in ongoing maintenance and capital expenditure costs per annum from 2050 compared to full electrification (and decarbonisation) of the electricity network.

And there is potential right now to bring new renewable gas sources – compatible with both Australia’s gas infrastructure – online relatively quickly.

Much of the focus on renewable gas to date has been on the potential for green hydrogen, generated using renewable electricity. Hydrogen will be an important fuel in our future – both Jemena and Australian Gas Networks are already blending green hydrogen into our networks – but the challenge is the technology and major hydrogen projects at the scale needed to decarbonise our gas networks are still some years away. Biomethane derived from biogas, however, is an opportunity Australia can act on much more immediately, with existing technology.

To simply describe biomethane, it’s biogas generated from waste in landfills, wastewater treatment plants and agriculture, after it’s been given an upgrade.

By removing contaminants and impurities, biomethane can be used in the same way as natural gas for heating, cooking and hot water for homes and for business and industry. It’s carbon-neutral, and there are potential sources of renewable biomethane right across the country, in proximity to existing gas infrastructure – meaning we can avoid costly infrastructure builds to bring energy to homes. And it will continue to provide consumers with options and choice in how they power their homes, without having to change or update their household appliances.

Power for 1.5m homes

Biomethane production can also be brought online relatively quickly. For example, our Malabar project was funded in 2020, and our intention is by the end of this year it will start blending enough renewable gas to meet the energy needs of more than 6000 homes in the gas network, with the potential to ramp up to the equivalent of 13,000 homes.

We expect the project – based at our partner Sydney Water’s Malabar Wastewater Treatment Plant and co-funded by the Australian Renewable Energy Agency - will remove 5,000 tonnes of carbon from being emitted into the atmosphere and potentially 11,000 tonnes if scaled up to its full potential.

At Jemena, we’ve identified more than 30 petajoules of potential sources of biomethane in proximity to our gas network. If these resources are fully utilised, they would provide enough energy annually for the roughly 1.5 million homes currently connected to our gas network.

And there are broader benefits for Australia in supporting the bioenergy sector beyond emissions reduction and energy security – the Australian Renewable Energy Agency’s Bioenergy Roadmap notes it has the potential to create around $10 billion in extra GDP, and 26,200 new jobs by the 2030s, as well as diverting an extra 6 per cent of waste from landfill.

Support to invest in renewable gas projects, including bioenergy projects, will help unleash this potential. However, to expand this emerging industry further, and tap into its potential to support Australia’s energy system, more support and investment will be required. Introducing a Renewable Gas Target, similar to the Renewable Energy Target for clean electricity introduced in the early 2000s, together with a national Green Gas Certification Scheme would be two ways in which the new Government could help support these emerging industries

When solving a complex jigsaw, sometimes it comes down to finding one or two critical pieces that can link with others so we can see the whole picture start to take shape. Renewable gases, including the oft-overlooked biomethane could be that critical piece as we look to solve the challenge of our energy future.