Exploring negative emission potential of biochar to achieve carbon neutrality goal in China

Authors analyze the potential of biochar in China, revealing it could sequester up to 0.92 billion tons of CO_2 per year with an average net cost of US$90 per ton of CO_2 in a sustainable manner, supporting carbon neutrality goal by 2060. Limiting global warming to within 1.5 °C might require large-scale deployment of premature negative emission technologies with potentially adverse effects on the key sustainable development goals. Biochar has been proposed as an established technology for carbon sequestration with co-benefits in terms of soil quality and crop yield. However, the considerable uncertainties that exist in the potential, cost, and deployment strategies of biochar systems at national level prevent its deployment in China. Here, we conduct a spatially explicit analysis to investigate the negative emission potential, economics, and priority deployment sites of biochar derived from multiple feedstocks in China. Results show that biochar has negative emission potential of up to 0.92 billion tons of CO_2 per year with an average net cost of US$90 per ton of CO_2 in a sustainable manner, which could satisfy the negative emission demands in most mitigation scenarios compatible with China’s target of carbon neutrality by 2060.