IMO Headquarters, London. File Image. Image Credit: Ship & BUnker

The United States is proposing a change to IMO biofuel rules that aims to tackle unintended deforestation from fuel crops, while at the same time giving a boost to U.S. ethanol production.

Specifically, Washington has challenged the IMO's approach to assessing the land use change risks of crop-based marine fuels  - a category dominated by ethanol - arguing that the current methodology contains a flaw that could allow fuels sourced from high-deforestation regions to qualify as sustainable under IMO rules.

In a submission to the 21st session of the Intersessional Working Group on GHG Emissions from Ships (ISWG-GHG 21/3/21), the US argues that the 2024 LCA Guidelines assess indirect land use change (ILUC) risk only within the boundaries of individual biofuel projects - which, since ILUC by definition occurs outside those boundaries, renders the assessment largely meaningless.

The U.S. proposes instead that the IMO adopt a regional-based approach, assigning ILUC risk according to observed deforestation levels in the vicinity of feedstock production, rather than within project fences.

Since global land use change emissions are concentrated in a small number of regions, Washington argues this is both scientifically grounded, practically workable, and would effectively disqualify fuels sourced from high-deforestation zones such as parts of Brazil and Southeast Asia.

While it does not mention U.S. ethanol production specifically, the submission's proposed framework would tend to favour fuels produced in temperate agricultural regions with low rates of land conversion - such as the US Corn Belt - over tropical alternatives.

The U.S. and Brazil are the world's two largest ethanol producers respectively.

The submission comes at a time when interest in ethanol as a marine fuel is genuine and growing.

Falling demand from road transport fuel blending, as electric vehicles displace gasoline, is leaving ethanol producers looking for new markets.

Marine shipping is a sector short on options for commercially sustainable ways to decarbonize.

At around $600 per tonne in the US, ethanol is a fraction of the cost of many alternatives such as green methanol.

Further, ethanol’s chemical similarity to methanol means the same engines and tanks can handle both fuels as alcohols.

In a recent interview with Ship & Bunker engine manufacturer WinGD described ethanol as a potential "game-changer" for shipping's energy transition.

Container line Maersk has already been trialling ethanol-methanol blends at sea.

The IMO working group is invited to incorporate regional ILUC risk assessment into the IMO's LCA framework ahead of MEPC 84, which meets in London from April 27 to May 1.