CCS Explained

Capture of carbon dioxide (CO2) and its geological storage (geosequestration), is known as Carbon Capture and Storage (CCS).

CCS is a technological process in which CO2 from emission sources such as power stations or industrial facilities is captured at the point of emission, transported via pipeline and stored deep underground for long-term storage to avoid its release into the atmosphere. The captured CO2 is compressed (via compressor station) to its super-critical liquid state before injecting (sequestering) the CO2 deep underground in geological formations such as depleted oil and gas fields and deep saline formations.

We now know the chosen Gippsland site is the nearshore area and, also, now know it was chosen based on the lowest cost option. That doesn’t mean it is the safest option.

Source – China Australia Geological Storage: CCS Opportunities in Victoria
Source – Basin-scale fluid flow in the Gippsland Basin:implications for geological carbon storage

‘A portfolio of prospective storage sites is under evaluation in the Gippsland Basin with the near shore / offshore areas being closely examined on account of the lower cost of development compared with sites further offshore.’  Source CSIRO – Basin Resource Management for Carbon Storage 2011, page 20

Cons:

  • As a process, CarbonNet’s Gippsland CCS project has potential risks associated with the transport of near pure CO2 via a 100km pipeline. See Pipeline failure
  • Injection process can lead to over-pressurising the formation resulting in fractures in upper seals potentially creating pathways for CO2 to leak through the caprock. See CO2 leakage
  • The injection site is at 1km depth and only 7km from the shoreline and human settlement in a moderate area of identified seal potential. Expected subsurface CO2 plume could interact with the freshwater interface and cause the onshore groundwater to become more saline.
  • CCS is an energy intensive project that deals with part of the wastestream of fossil fuel projects and just relocates it.
  • Will require long term monitoring of sequester site with costs largely born by the public.
  • The regulatory framework that would support CCS on a commercial scale is complex with the crown (government) ultimately taking responsibility. Read- Legal Liability and Carbon Capture and Storage (PDF 1MB)
  • Huge costs involved in establishing the CCS Flagship programs with projects needing to have a commitment from the state and industry to fund not less than two thirds of the projects non-commercial capital costs. This hasn’t occurred with the federal government funding much more than the proposed one third. https://www.anao.gov.au/work/performance-audit/low-emissions-technologies-fossil-fuels

Pros:

  • Injection of CO2 into offshore depleted oil fields can enhance oil recovery (EOR) and has been used by industry as a technique to get maximum extraction to increase profit margins. However, EOR has been used extensively in Texas with 2018 exposing growing sinkholes and environmental cost burdens.- Association between localized geohazards in West Texas and human activities.
  • Pipeline easements already exist reducing need to compulsory acquire properties. Although, the need to cross a Ramsar listed wetland and establish new pipe infrastructure through outer dune barrier is not without risk.

No one can say that CCS is beneficial to assist in reducing future greenhouse gas emissions (GHG) in the atmosphere when its aim is to prolong fossil fuel use which is not emissions neutral. Nor can it be used as an argument to reduce GHG when the concept (if successful) is years into the future and the problem exists now.

This technology requires a considered, transparent approach to address the potential complex environmental and regulatory risks from multi-user pipeline transport, pressurised injecting of CO2 deep underground and ongoing monitoring for CO2 leakage. Unfortunately, not all potential impacts are identified and/or inappropriately assessed which is what occurred with the nearshore 3D Seismic Survey in February ’18 off Golden Beach.  See Legal liability page.

Immediate concerns for the community are the containment of CO2 to prevent leakage and geomechanical assessment to prevent reactivating existing faults and fractures. Basing storage sites nearshore because of lower costs does not give the community confidence all risks and impacts can be appropriately prevented.