The International Maritime Organization has advanced work on global greenhouse gas regulations for shipping by agreeing on an illustration of a possible draft outline for an “IMO net-zero framework”.

The development came during the 81st session of the Maritime Environment Protection Committee, held in London from 18 to 22 March 2024. It represents a further step in the legal process for developing the mid-term GHG reduction measures identified in the revised IMO Strategy on the Reduction of GHG Emissions from Ships, adopted in July 2023.

The possible framework sets out how regulations under the International Convention for the Prevention of Pollution from Ships could be adopted or amended to introduce two central measures: a global marine fuel standard and a global pricing mechanism for maritime GHG emissions.

One option is a new Chapter 5 under MARPOL Annex VI. This could contain a goal-based fuel standard requiring the phased reduction of the GHG intensity of marine fuels, alongside one or more economic mechanisms intended to encourage the transition towards net-zero emissions.

The IMO stressed that several proposals covering the design of these measures remain under consideration. The outline is intended to provide a common structure for consolidating the different submissions and supporting further negotiations. It does not determine the final form of the regulations and may change as discussions continue.

Ahead of MEPC 82, scheduled for 30 September to 4 October 2024, the committee agreed that a comprehensive assessment of the proposed mid-term measures’ impact on Member States should be completed and submitted. A two-day expert workshop will examine the assessment’s preliminary findings, including modelling related to the distribution of revenue generated by the measures.

The Seventeenth Intersessional Working Group on Greenhouse Gas Emissions will then consider the impact assessment, the workshop’s conclusions and other submissions before reporting to MEPC 82. The working group will also prepare draft terms of reference for a fifth IMO GHG study.

MEPC 81 also established a GESAMP working group on the life-cycle GHG intensity of marine fuels. The group will provide scientific and technical assessments to support implementation of the IMO’s life-cycle assessment guidelines, which calculate emissions across fuel production and use on a well-to-wake basis.

Two correspondence groups will report to MEPC 83. One will develop a work plan for a regulatory framework covering onboard carbon capture systems and examine tank-to-wake methane and nitrous oxide emissions. The other will consider whether social and economic sustainability aspects of marine fuels should be incorporated into the life-cycle guidelines.

The committee also adopted revised life-cycle GHG intensity guidelines for marine fuels. The revisions include updated calculations for default emission factors, a revised template for submitting well-to-tank factors and a new template covering tank-to-wake emission factors.

Among its other decisions, MEPC 81 approved proposed emission control areas in Canadian Arctic waters and the Norwegian Sea for submission to MEPC 82, as well as recommendations on transporting plastic pellets in freight containers. It also advanced work on underwater noise, alternative-fuel guidelines and provisions under the Ballast Water Management Convention.