Through application to soil in farmer's fields, biochar both can help increase soil fertility and store carbon emissions. Photo: Feral Arts via flickr.
More new info on the potential of biochar to help combat climate change: A study in the journal Nature Communications shows that up to 12% of the world's greenhouse gas emissions caused by humans could be offset by producing biochar. What's more, the study calculates that's more than would be offset by producing energy from the same amount of biomass.Maximizing Biochar's Potential Requires Large Societal Commitment
In the study, researchers examined three different scenarios for levels biochar production: A maximum one, a minimum, and a middle scenario. All of these require "significant commitments from the general public and government" in the way we value carbon in biomass, notes study co-author Jim Amonette, from the Department of Energy's Pacific Northwest National Laboratory. In other words, it won't be easy.
In all scenarios, it was assumed that no agricultural or previous unmanaged lands would be converted to plantations for biomass production. Furthermore, the authors calculations included other sustainability criteria, such as ensuring enough biomass remained on the soil to prevent erosion, not using crop residue currently used for livestock feed, not applying biochar from treated building materials to soils, and more.
Which is all shorthand for the researchers tried to account for many common objections to using biochar due to unintended negative consequences.
1-1.8 Billion Metric Tons a Year Offset Possible
Here are the results, summed up in Science Daily:
Amonette and his colleagues found that the maximum scenario could offset up to the equivalent of 1.8 petagrams -- or 1.8 billion metric tons -- of carbon emissions annually and a total of 130 billion metric tons throughout in the first 100 years. Avoided emissions include the greenhouse gases carbon dioxide, methane and nitrous oxide. The estimated annual maximum offset is 12 percent of the 15.4 billion metric tons of greenhouse gas emissions that human activity adds to the atmosphere each year. Researchers also calculated that the minimal scenario could sequester just under 1 billion metric tons annually and 65 billion metric tons during the same period.
When they looked at the impact of using the same amount of biomass to produce energy, substituting for fossil fuels, the researchers found that in the maximum scenario at most 107 billion metric tons of carbon could be offset in the first 100 years of use. The benefits to carbon storage in soil of applying biochar was attributed as the cause of the difference.
Overview of the study's vision of how biochar can be deployed sustainably. View larger: Nature Communications
Efficient Pyrolysis Needed to Make Most of Biochar's Potential Jim Amonette again: "Roughly half of biochar's climate-mitigation potential is due to its carbon storage abilities. The rest depends on the efficient recovery of the energy created during pyrolysis and the positive feedback achieved when biochar is added to soil. All of these are needed for biochar to reach its full potential."
Read the original article: Sustainable biochar to mitigate global climate change
Like this? Follow me on Twitter and Facebook.
More on Biochar:
Jason Aramburu on the Promise of Biochar
Haiti's Rebuild May Be Biochar's Big Breakthrough
Reforestation & Biochar: Two Geoengineering Methods That Won't Cause More Harm Than Good
Biochar Reduces Nitrous Oxide Emissions From Soil by Three Quarters: Study