Waste coffee husk turned into a wonder material key to mitigating climate change
reasonstobecheerful.world
reasonstobecheerful.world
basically the carbon-negativity idea is that the charcoal isn't biodegradable so it will stay out of the atmosphere for a long time. also you can burn the gases produced (which actually contain most of the carbon) to keep them from releasing methane
The trailing “but” being that it all depends on proper utilization and the project in general. While biochar is carbon-negative, if there is enough carbon-positive emissions in a project it could offset the biochar, for instance.
https://www.sciencedirect.com/science/article/abs/pii/S00489...
https://pdfs.semanticscholar.org/fa23/220228abece8782396d287...