Draft amendments to the international marine pollution treaty to cut the carbon intensity of existing ships have been approved by the International Maritime Organization’s Marine Environment Protection Committee.
The draft amendments will now be put forward for formal adoption next year. The MARPOL treaty (the International Convention for the Prevention of Pollution from Ships) requires draft amendments to be circulated for a minimum six months before adoption. Changes enter into force after a minimum 16 months following adoption.
The draft amendments to MARPOL would require ships to combine a technical and an operational approach to reduce their carbon intensity.
Current requirements are based on the Energy Efficiency Design Index (EEDI) for new ships, which means that ships are designed and built to be more energy efficient than a baseline. There is also a mandatory Ship Energy Efficiency Management Plan (SEEMP) for all ships. The SEEMP requires ship operators to have a plan to improve energy efficiency through a variety of specific measures.
The draft amendments add further requirements by adding an assessment and measurement of the energy efficiency of all ships; they will also set required attainment values.
The draft includes a technical requirement to reduce carbon intensity, based on a new Energy Efficiency Existing Ship Index (EEXI), and an operational carbon intensity reduction requirement, based on a new operational carbon intensity indicator.
Energy Efficiency Existing Ship Index
EEXI will be calculated for ships of 400 gross tons* and above, in accordance with the different values set for ship types and size categories. This indicates the energy efficiency of the ship compared to a baseline. Ships are required to meet a specific required EEXI based on a required reduction factor (expressed as a percentage relative to the EEDI baseline).
Annual operational carbon intensity indicator
Ships are already required to collect date on fuel oil consumption. The carbon intensity indicator determines an annual reduction factor to ensure continuous improvement of the ship’s operational carbon intensity within a specific rating level.
The actual annual operational carbon intensity indicator will be documented and verified against an annual operational CII. This will enable an operational carbon intensity rating to be determined. The rating will be given on an A-E scale where “A” is “major superior” and “E” is “inferior performance”.
The performance level will be recorded in the ship’s Ship Energy Efficiency Management Plan.
A ship rated “D” or “E” for three consecutive years would have to submit a corrective action plan to show how a “C” level can be reached.
IMO greenhouse gas reductions strategy
The IMO’s initial greenhouse gas strategy envisages a reduction in carbon intensity of international shipping of 40% by 2030 and by 70% by 2050 when compared to 2008. The strategy calls for total annual GHG emissions from international shipping to be reduced by at least 50% by 2050 compared to 2008.
The strategy includes a specific reference to “a pathway of CO2 emissions reduction consistent with the Paris Agreement temperature goals” and with a revised strategy to be adopted in 2023.
* NOTE: a “gross ton” is NOT a measurement of weight. It is a measurement of the internal space inside an ocean-going ship.