A recent study synthesized existing research data on biochar as a carbon dioxide removal (CDR) method, identifying credible indications that it has the potential to be scaled to gigaton CO2 removal levels.
The review, authored by Australia-based researchers Zhe Han Weng and Annette L. Cowie, was published this month in Nature magazine.
In its essence, biochar, a charcoal-like porous material created through the pyrolysis of organic biomass that would otherwise decompose and release CO2 emissions, enables a solution for excess atmospheric carbon dioxide by absorbing it from the air and sequestering it in soil for hundreds to thousands of years.
While reviewing nineteen published studies on its impact, the research authors found estimates that project the biochar climate mitigation potential to be within a range of 0.03 to 11 Pg CO2 equivalent per year.
As the authors explain, these variations between studies come from differences in scope, definition of potential, and assumptions about biomass availability, biochar technologies, and reference systems.
Seven out of the nineteen reviewed studies were based on one and the same original study, meaning they weren’t carried out independently and from scratch.
On the other hand, the newer, independently carried out biochar assessments included in this review provided an estimated emissions mitigation potential of biochar systems at 2.6-10.3 Pg CO2 equivalent annually.
These projections, coming from credible sources cited in the review, paint an optimistic picture for the future of biochar development, where this decarbonization method could be scaled to remove gigaton levels of CO2.
Relevant: New Research: Beyond Sequestration, Biochar Enables Soil To Further Sorb Atmospheric CO2
As the authors clarify, the hopeful environmental scenario looks at biochar not only from a carbon removal standpoint, but it also takes into consideration other climate-forward benefits brought about from its implementation, like soil regeneration, greenhouse gas emissions mitigation, and displacement of fossil fuel emissions through use of syngas.
To be able to better understand and utilize this technology to its optimal environmental potential, the study authors call for new biochar assessments that would be based on integrated assessment models, which will include the latest knowledge on biochar processes and feedstock availability.
Read more: New Research Reveals The Efficiency And Energy Consumption Of Different CDR Methods
