Quite a few actually! Let’s briefly consider biochar used for soil amendment and as a carbon negative tool.
Biochar for soils: Soils are the basis of our food production system; they recycle waste products and are a vast storage centre for carbon, water and plant nutrients. What’s really fascinating is the role of biochar when it is applied in soils. That is because biochar improves soil fertility, water retention capacity, ph-value and aerobic porosity of soils. Also, biochar enhances micro-organic activity, which transforms it into a long lasting fertile and living black earth (Terra Preta).
Some biochars are enriched with selected natural nutrients and populated with billions of positive microorganisms. Enriched biochar has excellent fertilising effects on a purely organic basis: No mineral fertilisers, no peat, no chemicals. Together this will ensure long-lasting good soil fertility.
Research shows that biochar used as a soil amendment can improve crop yields substantially. Biochar amended soils should have greater nutrient use efficiency, lower leaching losses of nutrients and lower fertiliser requirements.
Biochar as a carbon negative tool: The UN’s IPCC and the Royal Society have both hailed biochar as a promising negative emissions technology.
By applying biochar to soil, the carbon in the biochar will be locked into the soil for hundreds of years and thus help reducing CO2 in the atmosphere. The carbonised material in the biochar contain around 3.6 times the amount of CO2 in it, which the plant has absorbed from the atmosphere to build its biomass. Applying biochar is therefore not only carbon neutral, but carbon negative and using it reduces your climate footprint.
We all know plants take in carbon dioxide in a process called photosynthesis, and this carbon is released when these plants are burned. What might not be as apparent is how most of the stored carbon in dead material is slowly released back into the atmosphere through eventual decay.
This is where pyrolysis comes in. Instead of being piled up and burned, or left in the field to rot, waste plant material is diverted into an oxygen limited chamber, called a retort. Here, through the application of heat, complex molecules present in the biomass are broken down either into gasses that can be easily condensed as wood vinegar, tar and bio-oil, or non-condensable gasses that be stored or burned for heat or electricity. Leftover from this process is a high-quality lump material we call biochar.