FacebookTwitterEmailLinkedin As biofuels have been attracting growing interest as a practical pathway toward lower-carbon shipping, the American Bureau of Shipping (ABS) published guidance outlining the use of biofuels in relation to Class requirements as well as European Union and IMO regulations. The guidance highlights the role of biofuels alongside other alternative energy sources, such as hydrogen and ammonia, in supporting the industry’s decarbonisation goals. In addition to reducing carbon emissions, biofuels with negligible sulfur content can help lower particulate matter and other air pollutants. The use of biofuels in shipping is already addressed under Regulation 18.3.2 of MARPOL Annex VI, which governs fuel oil quality requirements. Meanwhile, the international marine fuel standard ISO 8217 was revised in 2017 and updated again in 2024 to expand the allowable use of biofuel blends across existing and new marine fuel grades. ABS released the publication following revisions to the IMO’s interim guidance on biofuels under the Data Collection System (DCS) and Carbon Intensity Indicator (CII) framework, changes that are scheduled to take effect on 1 January 2027. IMO DCS and Attained Carbon Intensity Indicator (CII) MEPC 84 approved the revised interim guidance (MEPC.1/Circ.905/Rev.1), with an application date of 1 January 2027, aligned with the start of the next DCS data-collection year. The revised interim guidance requires that the CF of the biofuel blend be calculated as a weighted average of the CF of the respective fuels by mass instead of energy. It also clarifies that a biofuel blend should be treated as an equivalent fossil fuel type when the biogenic component is not certified. Any existing SEEMP Part II that includes a calculation method for the conversion factor of biofuel blends in accordance with MEPC.1/Circ.905 should be revised to reflect MEPC.1/Circ.905/Rev.1. The revised SEEMP Part II should be submitted for review as soon as possible to ens