International shipping currently accounts for about 2.9% of global greenhouse gas (GHG) emissions (around 1706 million tonnes of CO2 annually) and are increasing. The International Maritime Organisation (IMO) have projected that under a business-as-usual scenario, emissions could increase between 50% and 250% by 2050 if mitigation measures are not adopted. In October 2020, the IMO agreed legally binding targets to reduce the “emissions intensity” (emissions per unit of economic activity) by 40% compared with 2008 in the next 10 years. Following the adoption of the EU Measuring, Recording and Verification Regulation for shipping in 2015, the IMO established an IMO Data Collection System in 2018 that requires owners of large ships (above 5 000 gross tonnage) engaged in international shipping to report information on fuel consumption of their ships to the flag States of those ships.

This data is aggregated into an annual emissions report by the IMO, but there are no clear means of enforcing the mitigation targets that have been set, with emissions from international shipping are continuing to grow despite improvements being made on carbon intensity. The only IMO regulations currently in place to encourage greater shipping efficiency are the Energy Efficiency Design Index (EEDI) and the Ship Energy Efficiency Management Plan (SEEMP), which appear to be insufficient to drive the levels of improvement required to meet the ambitions set out. China and Russia remain strongly opposed to any robust measures being brought in, such as an emissions levy.

Technical and operational measures, such as slow steaming, weather routing, contra-rotating propellers and propulsion efficiency devices, can deliver cost effective fuel savings and mitigate emissions in the short term. However, in the mid to long term shipping is widely regarded as a “difficult-to-decarbonise” sector: few commercially available technologies can store and provide the energy required to move shipping over long distances, and the sector is a key enabler of international trade. Despite these challenges, several industries from the maritime shipping, fuel and infrastructure value chains have joined forces in the ‘Getting to Zero Coalition’ dedicated to commercialising deep-sea zero-emission vessels (ZEVs) by 2030 along with the associated infrastructure.

This POSTnote will examine existing commitments to mitigate emissions in the sector and outline the technologies that may help to achieve this.


Photo by Cameron Venti on Unsplash

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