At a red-brick factory in the German port city of Hamburg, cocoa bean shells go in one end, and out the other comes an amazing black powder with the potential to counter climate change.
The substance, dubbed biochar, is produced by heating the cocoa husks in an oxygen-free room to 600 degrees Celsius (1,112 Fahrenheit).
The process locks in greenhouse gases and the final product can be used as a fertilizer, or as an ingredient in the production of “green” concrete.
While the biochar industry is still in its infancy, the technology offers a novel way to remove carbon from the Earth’s atmosphere, experts say.