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Monday, May 31, 2021 

An IMO working group has agreed a set of draft guidelines to support mandatory measures to cut the carbon intensity of all ships, ahead of the forthcoming Marine Environment Protection Committee (MEPC) meeting.

The proposed mandatory measures have already been approved by MEPC and are expected to be adopted at MEPC 76 in mid-June 2021.  The proposed MARPOL amendments would require ships to combine a dual approach o reduce their carbon intensity, in line with the ambition of the Initial IMO GHG Strategy, and aiming to address both technical (how the ship is equipped and retrofitted) and operational measures (how the ship operates). The technical requirement is based on the Energy Efficiency Existing Ship Index (EEXI); and the operational carbon intensity reduction requirements, based on a new operational carbon intensity indicator (CII). This  

The Intersessional Working Group on Reduction of GHG Emissions from Ships (ISWG-GHG 8), which met remotely from 24-28 May, agreed, for consideration by the Committee, with a view to adoption a comprehensive set of guidelines accompanying the new requirements, to include: the method of EEXI calculation; survey and certification of the EEXI; shaft/engine power limitation system to comply with the EEXI requirements and use of a power reserve; operational carbon intensity indicators and CII calculation methods; reference lines for use with CII; CII Reduction factor Guidelines; and CII rating guidelines.

Under the draft MARPOL amendments, ships of 5,000gt and above have to determine their required annual operational carbon intensity indicator (CII). The ship’s CII determines the annual reduction factor needed to ensure continuous improvement of the ship’s operational carbon intensity within a specific rating level.  The actual annual operational CII achieved would be required to be documented and verified against the required annual operational CII. This would enable the operational carbon intensity rating to be determined.  

A key element in the draft guidelines is the proposal for the CII reduction factor (the ‘Z-factor’), included in the draft guidelines on the operational carbon intensity reduction factors relative to reference lines (G3). 

The group put forward to the Committee the concept of a phased approach, which would see an annual successive carbon intensity reduction rate of -2% compared to the 2019 reference line from 2023 (when the MARPOL amendments would enter into force) through to 2026 – at which time a review required under the draft MARPOL amendments would be undertaken. 

The Working Group agreed to establish a Correspondence Group on Carbon Intensity Reduction. The draft amendments would require the IMO to review the effectiveness of the implementation of the CII and EEXI requirements, by 1 January 2026 at the latest, and, if necessary, develop and adopt further amendments.

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