Compatibility study of mid-tier and detailed approaches for marine mobile emissions inventory in Durban port

Abstract Marine mobile emission inventories have been performed in many ports around the globe using different approaches. These approaches differ from one another in many ways and their results may show vast differences in terms of mass, volume, and the spatial concentration of emissions. Application of one method compared to another depends on many factors, including availability of resources, costs involved, capabilities and capacity of personnel conducting the inventory. To date, the activity-based method has been globally accepted as the modern way of conducting port emission inventories, particularly marine mobile emissions. This method uses emission factors based on the type of engine and fuel, and the load factors determined by the mode of operation. However, the activity-based method is also divided into different approaches namely, the detailed approach, the mid-tier approach, and the streamlined approach. Currently, there is no evidence showing that any of the existing methods has been used in South Africa and in most parts of Africa due to shortage of data and the capacity to conduct port emission inventories. This study is therefore aimed at utilizing both the detailed and the mid-tier approaches to conduct the Durban port marine mobile emissions inventory of five priority pollutants of NO 2 , SO 2 , PM 10 , HC, and CO 2 and compare the results for applicability in South African port emissions inventories. The results revealed a similarity in total emissions from both approaches, but vast differences when sources of pollution based on vessel type, engine type, and mode of operation were considered.