ABS analyses potential of biofuel blending on improvement to CII ratings
Analysis by ABS has concluded that drop-in biofuels have the potential to make a substantial improvement to a vessel’s Carbon Intensity Indicator (CII) rating. The research concludes that blending with biofuels could improve a vessel’s CII performance regardless of whether the vessel is powered by diesel, methanol or LNG.
The CII establishes a downward trajectory measurement of a ship’s carbon intensity, which is the amount of carbon emissions generated by a unit of transport work, equivalent to one nominal tonne of cargo carried over a nautical mile. The CII assigns an ‘energy efficiency’ rating to all ships (from A to E), based on the calculated carbon intensity.
Vessels in the D and E categories will have to demonstrate continuous improvement, moving progressively towards category C. Ships that spend three consecutive years in category D, or one year in category E will be subject to a mandatory review of the Ship Energy Efficiency Management Plan (SEEMP) and a plan of corrective actions must be made to achieve the Required Annual Operational CII.
The data produced by ABS is the result of an internal analysis conducted in advance of any potential change to the basis on which the IMO assesses emissions from merchant shipping. The current regime measures carbon emissions well-to-tank but there are discussions underway to change this to well-to-wake, accounting for the full lifecycle of emissions.
If the July meeting of the Marine Environment Protection Committee (MEPC) moves forward towards a lifecycle assessment (LCA) approach to emissions, the impact on demand for biofuels could be significant.
Blending the biofuel from biogenic sources with diesel and other fuels up to 30% would thus improve the overall carbon intensity and thus a ship’s CII rating. This improved rating was made on the basis of an exemption for the purposes of the research but should the IMO adopt a lifecycle approach to emissions accounting it could become a standard for fuel that is produced either from biogenic sources, renewable energy or includes a form of carbon recycling.
The ABS analysis concluded that a vessel propelled by heavy fuel oil could see its rating improved from D to A in 2023 with the addition of a 30% blend of biodiesel. Bio-methanol added at 30% would move a C-rated methanol-fueled vessel to an A rating today, and bio-methane at 30% would push an LNG-fueled vessel from a B rating to an A rating.
The advantage of biofuels to decarbonization extends to the supply chain and the bunkering infrastructure required for fuelling. Since biofuels are simple fuels of the same molecular structure, their cost is confined to the fuel itself rather than in any additional treatment, meaning they represent a compelling option once supply and regulatory questions are addressed.
The next issue for owners – common to all alternative fuels – is availability in sufficient quality to support CII compliance and ultimately a net zero carbon shipping industry. ABS expects there to be sufficient biofuel supply to meet current demand since the majority of energy majors have invested in producing sustainable biofuels.
Availability is increasing at the world’s big bunkering hubs and is expected to increase further over time as demand signals from shipowners grow. However, the shipping industry must be in no doubt that it will experience competition, principally from the aviation industry, which is also eyeing the use of sustainable biofuels to lower its carbon emissions.
Nevertheless, drop-in biofuels are a powerful tool for shipowners and operators to accelerate fleet decarbonization and improve their CII trajectory today. ABS is involved in pilot projects on the application of biofuels that have shown us the significant potential of these fuels to contribute to reducing a vessel’s tank-to-wake carbon intensity and transform its rating.
ABS has published a series of sustainability whitepapers focused on alternative fuels, breaking down the available options including their challenges and advantages, as well as other factors to take into consideration during the decision-making process. The whitepaper ‘Biofuels as Marine Fuel’ focuses specifically on drop-in biofuels and can be downloaded from the ABS website.
Source: By Mr. Panos Koutsourakis, VP Sustainability, ABS