Harnessing cocoa waste for biochar production and emission reduction to promote sustainability in West Africa

West Africa is a key player in cocoa cultivation, accounting for approximately 70% of world cocoa bean production. However, cocoa pod husk (CPH), an important by-product, remains largely underutilized. Therefore, this study provides the first comprehensive, multi-country assessment of CPH generation across seven major West African cocoa-producing countries namely Côte d'Ivoire, Ghana, Nigeria, Sierra Leone, Liberia, Guinea, and Togo over a 20-year period. It further assesses current management pathways and their environmental implications, with an evaluation of biochar as valorization approach. The data used in this study was gathered through field surveys and quantitative secondary data from FAOSTAT. Methane (CH4) emissions from decomposition of CPH were estimated based on IPCC methodologies, while biochar potential and carbon sequestration capacity were determined using established equations. The results showed that in 20 years, a total of 578 million tonnes of CPH were produced, with Côte d'Ivoire contributing the largest share with 331 million tonnes, followed by Ghana with 160 million tonnes. At present, on-farm abandonment remains the predominant management practice, emitting an estimated 17 million tonnes of carbon dioxide equivalent (CO2-eq) annually representing about 3% of Africa’s agricultural CH4 emissions. Conversion of this biomass into biochar represents a significant mitigation opportunity. The estimated annual production potential of CPH-biochar is 869 thousand tonnes, capable of sequestering about 1.59 million tonnes of CO2-eq per year. Adopting this approach could reduce greenhouse gas (GHG) emissions more than 18 million tonnes of CO2-eq, including avoided emissions and carbon sequestration. These findings highlight the importance of CPH-biochar production as a promising strategy for sustainable waste management.