Choosing the storage site
CarbonNet’s proposed carbon dioxide storage site in the offshore Gippsland Basin (in Bass Strait) is a very large geological structure shaped like an upside-down bath tub, with many rock layers.
The porous layers of sandstone can act like a sponge to store the CO2, while layers of shale and coal form the barriers which will trap the CO2 – the same way oil and gas has been trapped in Bass Strait for millions of years.
The site – Pelican – is large enough to store at least five million tonnes of CO2 per year for 25 years. That’s the equivalent of CO2 emissions from around one million cars every year.
Pelican site selection process
In 2009 the Carbon Storage Taskforce released its 'National Carbon Mapping and Infrastructure Plan – Australia (PDF)' report. The report identified the offshore Gippsland Basin as containing the highest quality and largest capacity carbon dioxide (CO2) storage reservoirs out of 25 major geological basins across Australia.
Since 2010 extensive scientific studies have been undertaken for potential storage sites across the basin.
Detailed three-dimensional models of the basin enabled geologists and reservoir engineers to analyse the sites and to predict the behaviour of CO2 throughout the storage process, from injection to migration and stabilisation.
Modelling of the sites was independently reviewed by Geoscience Australia, the British Geological Survey, CSIRO and the Geological Survey of Victoria, and externally certified by world-leading carbon capture and storage experts from Det Norske Veritas.
The sites were evaluated using similar methods to those used by the oil and gas industry (figure 1), with a focus on safe and secure long-term CO2 storage.
Initially, 14 sites were identified in the nearshore area. This was eventually reduced to three, with one site prioritised – Pelican – several kilometres off the coast of Ninety Mile Beach in Gippsland.
The benefits of a commercial-scale carbon capture, transport and storage service
The Carbon Storage Taskforce report stated that Australia’s first CO2 hub network would likely be located in the Latrobe Valley, due to its proximity to offshore CO2 storage sites and the competitive advantage of relatively low CO2 transport costs.
Successful implementation of the CarbonNet Project could be the starting point for an expanding commercial-scale carbon transportation and storage system, enabling new industries and investment in Victoria consistent with a net zero emissions by 2050 target.
Page last updated: 21 Apr 2020