Towards low carbon global supply chains: a multi-trade analysis of CO2 emission reductions in container shipping

The International Maritime Organization (IMO) has agreed in 2018 on a reduction of total greenhouse gas (GHG) emissions from international shipping, which should lower the total annual CO2 emissions by at least 50% by 2050 compared to 2008. Although extensive studies exist on the impact of international shipping at a global scale, few tools and empirical papers are available to assess the progress made so far in the shift towards carbon clean maritime supply chains. The paper identifies the key factors affecting CO2 emissions by container ships based on extant literature and business insights and measures how much has been already achieved in the past decade by offering multi-trade comparisons of the situations in 2007 and 2016. The paper concludes to a general decrease in annual CO2 emissions estimated at 33% since 2007. Two factors explain this decrease: first, the CO2 fuel efficiency in grams per TEU-km (−53%) due to the general decrease in speed and change in technology, and second, the decrease from changes in network design leading to less distance travelled (−21%). One factor counterbalances these positive effects, i.e. the increase in the total deployed fleet capacity, partly due to an increase in the number and average size of vessels (+81%). Finally, the paper discusses how these findings could be used by shippers and logistics service providers when designing cargo routing solutions in a supply chain setting based on their carbon efficiency