The technologies reviewed were permanent plantings, plantation and farm forestry, natural regeneration of native forest, avoided land clearing, savanna burning, soil carbon, blue carbon, pyrolysis biochar, geological storage (carbon capture and storage), bioenergy with carbon capture and storage (BECCS), direct air capture (DAC), and mineral carbonation.
The techniques that involve trees and other plants were identified as the ones with the highest sequestration potential. These mechanisms are followed by biochar, mineral carbonation and DAC, which are also efficient but are associated with higher costs.
According to the authors of the report, further research and development of these technologies are needed to bring down costs and increase national sequestration capabilities.
While the report considers the potential of each mechanism, it does not analyze the impact of competition for land, resources, or energy between different technologies.
These will be important considerations when it comes to implementation, as it will mean realizable sequestration is likely considerably lower than technical and economic potential sequestration estimates provided in the report.
“No single technology will get us there. An integrated and optimized portfolio of technologies will be required,” Andrew Lenton, head of CSIRO’s CarbonLock Future Science Platform, said in a media statement.
In Lenton’s view, a comprehensive integrated assessment modelling approach will need to quantify potential and feasible sequestration opportunities and guide development at the national and regional scales.
The report will inform an Insights Paper on carbon sequestration being published by the Climate Change Authority, which will, in turn, help inform the advice to the government on Australia’s 2035 emissions reduction target.