At Resources Future, we continuously seek innovative climate solutions that drive meaningful impact. Our climate change consultant, Minha Hanif, recently had the remarkable opportunity to be part of the DAAD-funded AssessGHG-RemoveC project at NUST, specifically attending the Biochar Academy. The Biochar Academy pooled in world-class minds and ideas, made possible by the faculty from Hochschule Geisenheim University and Atta-ur-Rahman School of Biosciences, NUST. This summer school presented an immersive learning experience into the world of carbon sequestration through biochar, a powerful solution for combating climate change.
The Biochar Academy opened with the physical, chemical, and biological processes driving greenhouse gas fluxes; the carbon and nitrogen cycles that occur naturally in the environment. To understand the role biochar plays, imagine carbon being “locked away” in one of the stages of this cycle; the soil. This is how the carbon dioxide levels increasing in the atmosphere can be countered using biochar.
Biochar is a stable form of carbon produced from biomass that has undergone pyrolysis. The process was also demonstrated practically at the Biochar Academy in a “Kon-Tiki” kiln, originally developed in Germany, but replicated by NUST (making their own patented version). The biomass used for the experiment consisted of corn peels and cobs, with wood layered below which is kindled first for a clean start of the pyrolysis. It was demonstrated how biochar is produced in layers; when one layer is pyrolyzed with white ash becoming visible, the second layer of biomass is then topped on it, and the process is continued. Once the Kon-Tiki kiln is at capacity, the process is halted by “quenching” with water. Ideally, the water should be pooled in from the bottom of the kiln to prevent it from being vaporized, but misting is effective as well. Excess water was drained, and the remaining slurry comprised of activated biochar.
When biochar is being produced to increase soil fertility, quenching can be done with various other chemicals. Projects done in Kathmandu, as described during one of the lectures in the workshop, collected cow urine as the quenching liquid, essentially locking away the fertilizer nutrients within the biochar. The biochar is then applied, below, on top, or around the saplings (in trenches), which showed promising increases in growth rates in plants. The biochar acts as a sponge, thanks to its porous nature, retaining nutrients in the soil over long periods of time instead of leaching into the ground and becoming unavailable for the plants. Microbial activities are also shown to have been increased in the presence of biochar which facilitate the uptake of nutrients in the roots. Of course, as many of the industry and academic experts in the Biochar Academy emphasized, the level of refinement of the biochar plays a huge part in the benefits reaped by this improved method of fertilizing crop saplings. The more refined the process is (e.g Pyreg’s industrial pyrolysis plants), the more expensive the biochar, and less significant change in yield than coarser biochar. Which is why, most farmers are advised to use the coarser biochar produced on lower temperatures, which optimise the cost-effectiveness and returns. Stephen Joseph, author of “A farmer’s guide to the production, use and application of biochar”, presented a brief overview of his book, and our consultant highly recommends giving it a read!
A good question to ask here is, what benefits are there of more refined biochar, pyrolyzed at higher temperatures? Highly refined biochar is used as an environmentally friendly construction material. Since it also means locking away carbon within built infrastructure for years to come, it also contributes to carbon sequestration. A good example of this was demonstrated during one the lectures on using biochar in urban landscape planning, where it the multipurpose use was highlighted in urban images, where buildings were constructed with biochar and also used as a fertilizer catalyst within the trees and plants in urban settings, watered with the wastewater of the adjacent buildings.
The Biochar Academy tied existing practices of biochar use with their potential in the carbon market. With speakers from Carbon Standards International and CarbonFuture, the rising significance of biochar application for carbon sequestration was discussed. The founder of Husk, expanded on her journey of producing biochar and becoming a carbon sink manager of carbon credit projects. The founder of Pyreg GmbH also reflected on his clients’ success in generating carbon credits.
As part of the Biochar Academy, Minha developed a concept for a carbon credit project with her team, emphasizing on biochar application. Aligning with her passion for clean cooking, Minha proposed the use of a Top-Lit Updraft (TLUD) biochar cookstove. The villages for the carbon project were identified, where farmers could use the same biomass that is used for open-fire cooking, as fuel for the TLUD cookstoves. The biochar produced in the cookstoves could then be used as fertilizer. The TLUD cookstove works in a similar way to a Kon-Tiki kiln, whereas the heat is directly used for cooking. TLUD cookstoves can be sized up or down to match the cooking habits of the targeted population. This concept is a triple edged sword, combating public health issues and environmental degradation while being a financially self-sustaining initiative.
The key takeaway from the Biochar Academy was understanding the “jack-of-all-trades” nature of biochar and relating its broader success in South Asia to Pakistan’s context. This not-so-secret ingredient to climate action could make the world of a difference in how we, an agrarian economy, can use it to elevate our climate action trajectories and reaping all the additional benefits of improving soil health, reducing water use and growing healthier crops.
