Hamburg, a German port city, is home to an innovative red-brick factory where discarded cocoa bean shells are transformed into a remarkable black powder known as biochar. This pioneering substance might prove to be a game changer in the fight against climate change.
Biochar, produced by heating cocoa shells to 600 degrees Celsius without oxygen, is a unique process that sequesters greenhouse gases. The end product has diverse applications; it can be used as a green fertilizer, an ingredient in eco-friendly concrete, or as a method to store carbon.
Despite the infancy of the biochar industry, it holds tremendous potential to capture carbon from the atmosphere. The UN’s Intergovernmental Panel on Climate Change (IPCC) suggests biochar could potentially sequester 2.6 billion of the 40 billion tonnes of CO2 humans produce annually. However, scaling this technology remains a considerable challenge.
Circular Carbon’s CEO Peik Stenlund stated, “We are reversing the carbon cycle” at the Hamburg biochar plant, one of Europe’s largest. The plant utilizes spent cocoa shells from a nearby chocolate factory, sequestering the CO2 within the shells, which would otherwise be released during decomposition.
David Houben, an environmental scientist at France’s UniLaSalle institute, says that carbon can be stored in biochar “for centuries”. Each ton of biochar or bio coal can contain the equivalent of 2.5 to 3 tons of CO2.
Historically, indigenous populations in the Americas utilized biochar as a fertilizer. Its rediscovery in the 20th century arose from scientists studying highly fertile soils in the Amazon basin. Biochar’s unique structure aids crops by enhancing soil’s water and nutrient absorption capabilities.
Despite the promise of this technique, there are hurdles to be overcome for widespread adoption. These include adapting to different soil types, localizing the process to limit carbon emissions from transport, and overcoming the high costs currently associated with its production.
Houben suggests that beyond agriculture, other sectors such as construction could use biochar, specifically in the manufacture of ‘green’ concrete. Another proposed revenue source is selling carbon certificates to companies aiming to offset their emissions.
With biochar included in Europe’s regulated carbon certificate system, CEO Stenlund anticipates strong growth in the sector. His company is planning to open three additional production sites soon.
Across Europe, biochar projects are on the rise. The biochar industry federation predicts that production could double to 90,000 tonnes this year, compared to 2022.