IMO: More efficient container and general cargo ships are on the horizon, but don’t pick on the small guys

On October 26, 2018, the International Maritime Organization (IMO) tentatively agreed to make some new ships more efficient in what will be an important step towards implementing the organization’s initial greenhouse gas (GHG) strategy. But that’s on hold to address equity concerns.

At the 73rd session of IMO’s Marine Environment Protection Committee (MEPC 73) meeting, IMO tentatively agreed to require new container ships to be 40% less carbon intensive by 2022 than those built between 1999-2008 under IMO’s Energy Efficiency Design Index (EEDI) regulations. The target was 30% less carbon intensive by 2025, so, if implemented, it will be a good step forward for the container shipping industry. Additionally, new general cargo ships will need to be 30% less carbon intensive in 2022 instead of 2025 under the proposal. Ultimately, IMO agreed to make its final decision at MEPC 74 in May 2019 so the committee can consider Member State and industry concerns that smaller container ships that serve smaller ports and countries (including small island developing states) might be unfairly impacted. At the same time, IMO will also consider whether to tighten EEDI standards for oil tankers, chemical tankers, gas carriers, bulk carriers, and cruise ships.

What will this decision mean for emissions and for further efforts to reduce climate pollution from ships? Currently, container ships account for 26% of emissions from international shipping and general cargo ships account for 6.5%. If IMO follows through with strengthening the EEDI standards for these ships, it will save over 750 million tonnes of cumulative carbon dioxide (CO2) emissions between 2022 and 2050, according to our models. That’s equivalent to total CO2 emissions from the international shipping sector in 2010.

To date, the EEDI has been too weak to compel the use of innovative technologies and fuels that reduce the carbon intensity of ships, which has instead encouraged incremental improvements in conventional fossil fuel ships. If IMO moves up and strengthens the efficiency standards for new container and general cargo ships, it will improve the probability of achieving IMO’s minimum 2050 emissions reduction target and send a signal to shipyards that they will need to build much more efficient ships in the near future. Strengthening the EEDI can change the way ships are designed, fueled, and propelled and can drive the deployment of zero emission vessels (ZEVs). But, until next May at least, the standards remain as agreed to back in 2011.

A proposal to regulate ship speeds in order to reduce fuel consumption and emissions was considered, but no decision was made on this or on any other action that would reduce emissions from the existing fleet. No action means that the IMO has only a 17% probability of achieving its minimum 2050 emissions reduction target, according to our analysis (far left box-and-whisker plot in the Figure). If IMO accelerates the EEDI targets for all ships, not just container and general cargo ships, that probability would double. Accelerating efficiency standards for all ships and slowing the fleet down by 10% would be needed for even odds to meet the 2050 goal.

IMO emissions with improvements and ship slowdowns
2050 International Shipping CO2 emissions (million tonnes, Mt) and associated probability (P) of meeting IMO’s minimum 2050 emissions target by improving technical efficiency and implementing speed reduction.

According to the Intergovernmental Panel on Climate Change, the world’s remaining carbon budget in 2018 is 570 billion tonnes of CO2 for a 67% chance of limiting warming to 1.5° C. If we optimistically assume that international shipping will account for 2.3% of anthropogenic emissions in the future (emitting about 0.8 billion tonnes of CO2 per year), the sector has a little over 12 billion tonnes, or about 15 years, of CO2 remaining. That means we need immediate actions to reduce emissions from the sector and to chart a course towards zero emission vessels.

The IMO will finalize its decision on the revised EEDI targets at MEPC 74 in May 2019. As we said earlier, our analysis shows that making new ships more efficient and slowing ships down can significantly improve the chances of meeting or exceeding IMO’s minimum 2050 emissions target. Next up for us, once we shake off our jet lag back in the States, is to publish new research on the fuel savings and emissions reduction potential of wind-assist and hull air lubrication technologies for submission to MEPC 74. We’ll also continue to engage with IMO member states and organizations, including industry, to finalize mandatory measures that decarbonize the international shipping sector. Until then, cheers from London.