Interim guidance on the use of biofuels under regulations 26, 27, and 28 of MARPOL Annex VI (DCS and CII)

The International Maritime Organization on 24 July 2023 released the MEPC.1/Circ.905, Interim guidance on the use of biofuels under regulations 26, 27, and 28 of MARPOL Annex VI (DCS and CII).

The Marine Environment Protection Committee, at its eightieth session (3 to 7 July 2023), approved the Interim guidance on the use of biofuels under regulations 26, 27 and 28 of MARPOL Annex VI (DCS and CII), as set out in the annex.

Member Governments are invited to bring the annexed Interim Guidance to the attention of their Administrations, shipowners, ship operators, fuel oil suppliers and any other interested relevant stakeholders concerned for application as of 1 October 2023.

Annex: Interim guidance on the use of biofuels under regulations 26, 27, and 28 of MARPOL Annex VI (DCS and CII)

The 2022 Guidelines on operational carbon intensity indicators and the calculation methods (resolution MEPC.352(78) CII Guidelines, G1) provide the possibility for the CO2 Emission Conversion Factor (Cf) to be obtained from the fuel oil supplier, supported by documentary evidence, in case the type of the fuel oil is not covered by the relevant guidelines.

Pending the development of the comprehensive method to account for well-to-wake GHG emissions and removals based on the Guidelines on life cycle GHG intensity of marine fuels (LCA Guidelines) (resolution MEPC 376(80)), biofuels that have been certified by an international certification scheme,* meeting its sustainability criteria, and that provide a well-to-wake GHG emissions reduction of at least 65% compared to the well-to-wake emissions of fossil MGO of 94 gCO2e/MJ (i.e. achieving an emissions intensity not exceeding 33 gCO2e/MJ) according to that certification, may be assigned a Cf equal to the value of the well-to-wake GHG emissions of the fuel according to the certificate (expressed in gCO2eq/MJ) multiplied by its lower calorific value (LCV, expressed in MJ/g) for the purpose of regulations 26, 27, and 28 of MARPOL Annex VI for the corresponding amount of fuels consumed by the ship.

*Refer to ICAO's Approved Sustainability Certification Schemes and the CORSIA Sustainability Criteria (chapter 2) for CORSIA Eligible Fuels

In any case, the Cf value of a biofuel cannot be less than 0. For blends, the Cf should be based on the weighted average of the Cf for the respective amount of fuels by energy.

A Proof of Sustainability or similar documentation from a recognized scheme should be provided along with the Bunker Delivery Note, to facilitate the verification of the reported biofuel consumption.

Biofuels not certified as "sustainable" or not fulfilling the well-to-wake emission factor criterion above should be assigned a Cf equal to the Cf of the equivalent fossil fuel type.

This guidance should be considered as an interim simplified method until a more comprehensive method is developed to calculate a fuel's Emission Conversion Factor reflecting its well-to-wake GHG emissions and removals based on the LCA Guidelines.

This guidance does not intend to prejudge or delay the process of developing such a comprehensive method.

This Interim Guidance will be rescinded immediately upon operationalization of a well-to-wake GHG methodology through the LCA Guidelines.

Administrations are invited to inform the Committee on which international certification schemes have been used when applying this guidance.


For more information, please see the document below (available only to subscribers):


Interim guidance on the use of biofuels under regulations 26, 27 and 28 of MARPOL Annex VI (DCS and CII)