A Comparative Analysis of Shipping Emissions Estimation Methodologies and their Applicability

The shipping emissions estimation method is the premise and basis of making shipping emissions inventory, assessing the impact of shipping emissions, and promoting the work of energy saving and emissions reduction in transportation industry. The article analyzed the three main kinds of current representative shipping emissions estimation methods, i.e. simplified methodology and detailed methodology for estimating air pollutant emissions from ships presented by Techne Consulting, Tier1 and Tier2 methods from IPCC, and default approach, technology specific approach and ship movement methodology proposed by EMEP. Based on a comparative analysis of the characteristics of these estimation methods and their applicability, it was shown that: (1) the three kinds of methods from Techne Consulting, IPCC and EMEP are essentially the same, that is the emission equals to the product of the level of activities and emission factors, the difference lies in the level of detail of the activities are broken down; (2) the three shipping emissions calculation methods proposed by EMEP can be considered as the comprehensive and representative method, the default approach is a top-down method, and the technology specific approach and ship movement methodology are bottom-up approaches; (3) different methods have different applicability, the default approach proposed by EMEP is recommended to estimate CO2, SO2 emissions from shipping, and the technology specific approach and ship movement methodology are suitable for estimating the emissions of the other pollutants.