Carbon footprint of fertilizer imports to the East African Bloc and policy recommendations for decarbonization

Background: Almost all nitrogenous (N) fertilizers are fixed on an enormous scale using the Haber-Bosch ammonia synthesis process via a reaction of Nitrogen with hydrogen in the presence of a catalyst. This process is a leading global polluter, emitting 830 megatons of CO2 to the atmosphere annually. On the other hand, the global transport sector emits 7.5 gigatons of CO2 yet the fraction of emissions from freight transportation of N fertilizers from exporting countries to the East African (EA) Bloc is not known. This study examined the carbon footprint from freight transportation of N fertilizers. The findings are useful in the regions’ nationally determined contributions (NDCs) as per the Paris Agreement of December 2015 regarding downsizing emissions from the transport sector. Methods: The study area included five EA Community (EAC) countries namely, Kenya, Uganda, Tanzania, Rwanda and Burundi. Statistics of fertilizers were obtained from https://africafertilizer.org/. The carbon footprint calculator (CFC) for fertilizer production (obtained from https://www.fertilizerseurope.com/), certified by the Carbon Trust Standard, was used. Results: Over 93% of fertilizers imported to the EA Bloc are N fertilizers, leaving a carbon footprint of 4.9 megatons CO2-eq. Of these emissions, 1.1 megatons CO2-eq were contributed by imports from Saudi Arabia and 0.8 megatons CO2-eq from China. The ‘dirtiest’ of N fertilizers that accounted for the highest carbon footprint on the EA bloc were urea ammonium nitrate, calcium nitrate, nitrophosphates and ammonium sulphate. Conclusions: Every metric ton of N imported results in a carbon footprint of 4.5 metric tons CO2-eq. The Ammonia production process of exporting countries, freight distance, choice and number of N fertilizers imported are significant determinants of greenhouse gas emissions to East Africa’s NDCs. To reach net-zero emissions the EA community needs to invest in new processes, circular economy and decarbonization pathways.