Biochar is a good tool for climate mitigation
We need to make sure we don't repeat the mistakes of biofuels. But the risks are avoidable
- The Guardian, Tuesday 8 September 2009
Your article reports on those who warn that the development of biochar could repeat the disastrous mistakes surrounding biofuels (Charcoal burial to help planet is no miracle cure say sceptics, August 28). It quotes Friends of the Earth campaigner Mike Childs as saying: "The problems with biochar are largely the same as biofuels." This is simply not the case. Biofuels depend entirely on misguided subsidies – they are effectively a payment to farmers to burn food surpluses. If those subsidies were spent on solar and other renewable sources of energy we would have more food and be less dependent on fossil fuels.
There is a strong case for the responsible development of biochar as a tool for climate mitigation and for the restoration of agricultural land which has been degraded by decades of industrial agriculture. Simple and inexpensive modern equipment can capture 70% of the carbon in biomass as biochar, double traditional charcoal-making processes. Producing biochar from farm and forestry waste prevents it being burned or left to rot, both of which put 100% of the carbon back into the atmosphere as CO2 or methane.
Biochar is made at farm scale and requires minimal management time. Small and medium farmers will be the main beneficiaries.
The article quotes George Monbiot's criticism of biochar: "The idea that biochar is a universal solution that can be safely deployed on a vast scale is as misguided as Mao Zedong's Great Leap Backwards." We share Monbiot's view, but the article could also have quoted Monbiot's other comments: "None of this is to suggest that the idea has no virtues… Nor does this mean that charcoal can't be made on a small scale, from material that would otherwise go to waste"; and on his blog: "By all means, let's use genuine waste – whether from crops, forestry, sewage or food – to make biochar."
At Carbon Gold we have developed and are applying simple systems that we believe are the way forward. Large-scale enterprises founder on the cost of hauling bulky biomass long distances and then hauling the biochar back. As a result we are already working with farmers to convert agricultural wastes into biochar.
The UN Convention to Combat Desertification is leading the way on including biochar in the forthcoming Copenhagen climate-change talks. The Maldives, the country most threatened by rising sea levels, includes biochar in its plan to be zero carbon.
In Belize farmers are increasing their income by turning cacao prunings and shade trimmings into biochar. Large amounts of olive, citrus, vine and other tree crop prunings, along with rice husks and forestry wastes, are burned or left to rot every year. Turning these into biochar will help producers to improve fertility and soil structure and generate additional income from carbon sequestration.
We are at the early stages of one of the most exciting and realistic means of reducing greenhouse gas levels. We need to make sure we don't repeat the mistakes of biofuels. But the risks have been identified and can be avoided.
Craig Sams is a co-founder of the biochar company Carbon Gold, and was a founder of Green & Blacks chocolate