With a 470 Gt storage capacity, Australia is geologically positioned to be a global leader in carbon capture. How does the country move past politics to solve the integration challenge?
Carbon capture and storage (CCS) is often described as a future technology. Yet when examined through an engineering lens, much of the system is built on established technologies.
That’s one of the central insights of the recently released Carbon Capture & Storage (CCS) Briefing Paper from Engineers Australia, a document that deliberately breaks the technology into its functional components and assesses each on technical merit.
For Simon Flowers FIEAust CPEng, Chair of the Engineers Australia CCS Working Group, the CCS discussion is almost impossible to divorce from the political and social debate surrounding its use and efficacy in the pursuit of net zero.
This provided the catalyst for an objective analysis of CCS technologies designed to provide guidance on the challenges and the opportunities of deploying CCS in the Australian context.
“We wanted to cut through the noise and look at this using systems-based approach,” Flowers told create. “Capture, transport and storage: analyse each of those parts and understand what is proven, what is mature and where the challenges sit.”
Established building blocks
By capturing and storing large volumes of CO₂ in underground reservoirs, CCS is typically regarded as one of the mitigation options for emissions reduction in hard-to-abate industries such as steel and cement manufacturing, the production of industrial chemicals and fertilisers, natural gas processing and methane-based hydrogen production (blue hydrogen).
From a purely technical standpoint, CCS is not an exotic frontier technology but an integration challenge.
“One of the revelations of the paper for everyone was that none of this technology is new,” Flowers said.
As he explained, post-combustion capture relies on established chemical processes. Many heavy industrial facilities, such as cement and steel plants, already produce relatively concentrated CO₂ waste streams, which reduces the energy required to further purify the gas to pipeline-ready specifications.
Transport is similarly familiar territory. Moving CO₂ via pipeline involves well-understood materials technology, compression systems and flow assurance practices.
“When you break it into its component parts, there’s nothing unusual about this from an engineering perspective,” Flowers said. “The pumps are still pumps. The pipelines are still pipelines. The subsurface work builds on existing knowledge.”
The subsurface challenge
The most complex aspect to CCS sits far underground – but therein also lies Australia’s opportunity. As the paper notes, Australia possesses vast geological storage capacity for CO₂, “positioning the nation as a globally significant resource for CCS”.
The total estimated geological storage potential for Australia ranges up to 470 Gt. By comparison, Australia’s current annual total greenhouse gas emissions (including all GHGs converted to CO2-e) are approximately 0.44 Gt CO2-e per annum.
Much of the storage capacity lies in depleted oil and gas reservoirs, primarily in offshore sedimentary basins. These depleted reservoirs are geologically well understood, Flowers said, and provide sunk cost benefits at the front end.
“They are a known entity, so they are the lowest risk. Oil and gas companies have assessed them. They’ve been watching production profiles. They’ve got the cap rock. They’ve got all the geotechnical data over the 30 to 40 years of their life in production.”
Click on the interactive map below to explore a selection of key CCS sites around Australia. The teal cloud icon indicates a facility already in operation, the spanner icon marks one in advanced development, and an exclamation mark indicates a location in early development.
Saline aquifers, while offering significant theoretical capacity, are less straightforward. If permeability or injectivity assumptions prove overly optimistic, projects can underperform, as evidenced by US energy giant Chevron’s Gorgon project in Western Australia – the world’s largest operational CCS project – which has to date buried less CO₂ than originally modelled.
The economics of proximity
The engineering behind CCS is largely known, but the economics remains a variable, with critics pointing to cost as its fatal flaw. The briefing paper highlights shared infrastructure as one of the most effective levers for improving economic performance.
The emerging “hub” model, clusters multiple heavy emitters around common transport and storage assets, reframing CCS from a bolt-on retrofit to a piece of strategic industrial planning.
By aggregating CO₂ streams from several facilities, hubs distribute capital and operating costs across users. Proximity to storage sites further reduces pipeline length and compression requirements further reducing cost challenges.
“Multi-user, shared infrastructure is critical,” Flowers said. “The closer the multiple emitters are to the storage site, the lower the cost.”
High-purity advantage
Another important technical consideration is CO₂ purity. Many hard-to-abate industries produce waste gas streams with relatively high CO₂ concentrations. That simplifies the capture process compared to extracting CO₂ directly from ambient air.
Direct air capture (DAC) technologies, while advancing, must separate CO₂ from very low atmospheric concentrations (typically <0.05 per cent). This requires substantial energy input and processing to achieve pipeline-grade purity. For that reason, the briefing paper excluded DAC to deliberately focus on industrial CCS, where capture is more technically and economically straightforward.
That distinction is not a dismissal of DAC, Flowers said, but a reflection of technology readiness. DAC remains an area of active innovation, particularly on the capture front end. Crucially, the early establishment of industrial CCS hubs – with their shared transport and storage infrastructure – presents a compelling “plug-in” opportunity for DAC as it matures.
By “bolting on” to these established networks, DAC can transition from a nascent technology into a scalable net-negative emission abatement tool, effectively removing CO₂ from the atmosphere using the same downstream systems built for industrial emitters.
A systems lens
The working paper reframes CCS as an engineering integration challenge grounded in established practice. The remaining work lies in optimisation, scaling and closely monitored execution. This depends on regulatory clarity, particularly around long-term liability for stored CO₂, approval processes and monitoring obligations.
“This is a systems integration challenge,” Flowers said. “The technologies exist. The question is how we refine them, reduce energy penalties, lower cost and manage long term subsurface risk.”
Public trust in CCS is another variable. Concerns about leakage and long-term liability are persistent. CCS projects must demonstrate transparent monitoring, clear reporting and robust risk management. For Flowers, this is where the engineering profession finds its most critical mandate. By sitting at the decision-making table, engineers can help translate complex systems into understandable narratives without compromising technical rigour.
The formation of the member-led working group serves as a prime example of this “journey” in action. By bringing together diverse expertise to produce an objective, evidence-based briefing paper, the group has demonstrated how professional bodies can provide a credible, transparent foundation for both policymakers and the community.
As Flowers notes: “The goal is to lead with facts and open dialogue, ensuring that as the technology scales, the public is not just a spectator, but an informed participant in the transition.”
Read the full working paper.
