The rulebook that still doesn't exist

Shipping is the one large transport sector without a global carbon rule, and the body meant to write one has now missed two deadlines to do it. The IMO's Marine Environment Protection Committee approved its Net-Zero Framework in principle at MEPC 83 in April 2025: two linked instruments, a Global Fuel Standard that steadily tightens the greenhouse-gas intensity ships are allowed to burn, and a companion carbon-pricing mechanism to fund the transition and penalise ships that don't comply. Formal adoption was scheduled for an extraordinary session that October — and failed. Iran, Iraq, Bahrain, Kuwait, Saudi Arabia, the UAE, Venezuela and Yemen led opposition, and the United States pushed hard against the framework as well; the session adjourned the vote by a year rather than reject the text outright. Momentum partly recovered at MEPC 84 in April–May 2026: a majority of member states now back the framework roughly as originally drafted, and rival proposals floated in London failed to gather real support. But recovered momentum is not adoption. The next chance is a resumed Second Extraordinary Session on 4 December 2026, alongside the regularly scheduled MEPC 85. This blog's own reporting already covers what the framework's actual numeric targets are — the GHG Fuel Intensity cuts and the $100-a-tonne carbon price attached to them — in detail; this piece's focus is the adoption saga around that framework, not its mechanics.

The fuel that didn't wait for the rule: LNG

While IMO deliberated, shipowners kept ordering LNG-fuelled tonnage anyway. Clarksons Research puts LNG's share of all alternative-fuel tonnage ordered in 2026 at roughly 80%, up from 75% the year before — dominance the firm attributes largely to green methanol's and ammonia's own unresolved availability and bunkering-infrastructure problems, not to LNG being cleaner on paper. The LNG-capable fleet, excluding LNG carriers themselves, now numbers around 900 vessels, with roughly 200 delivered in 2025 alone. The dedicated LNG bunker-vessel fleet — the ships that refuel other ships — has grown from 9 vessels in 2017 to 67 today, with 42 more under construction through 2029, a fleet Clarksons and other trackers expect to grow more than 60% within three years. Bunkering itself is now available at 222 ports worldwide, with 62 more planned, and DNV forecasts LNG consumption by LNG-fuelled ships to rise a further 167% between 2025 and 2030 after already growing more than 500% between 2020 and 2024.

The fuel regulation already forces: biodiesel blending

Unlike IMO's stalled framework, the European Union's FuelEU Maritime regulation is already in force and does not wait for global consensus: ships trading into or out of the EU and European Economic Area must cut the greenhouse-gas intensity of the energy they use, on a schedule that tightens over time, and every ship needed a valid FuelEU Document of Compliance by 30 June 2026. Waste-based biodiesel blends are one of the regulation's explicitly compliant pathways, provided they're certified under the International Sustainability and Carbon Certification scheme (ISCC-EU): B30 (30% biodiesel, 70% fossil marine diesel) and B60 (60/40) are both named as usable blends, and a certified biofuel achieving at least a 65% greenhouse-gas-intensity reduction against the fossil baseline can be treated as "zero emission" under the rule's own accounting. This blog's own reporting on the broader used-cooking-oil trade covers where the waste-based feedstock behind much of this biodiesel actually comes from, and the fraud risk that trade carries; that ground isn't repeated here.

The novel end of this market is fuels that aren't conventional FAME biodiesel at all but are engineered to behave like a drop-in replacement anyway. MASH Makes, a Danish-founded biofuel producer, makes its fuel via pyrolysis of cashew-nut-shell liquid (CNSL) — an agricultural residue, not a food-competing feedstock — in a process the company describes as carbon-negative because it co-produces biochar, which locks carbon into a stable solid rather than releasing it. In 2026, MASH Makes and Danish shipowner DS NORDEN completed what both companies describe as a world-first commercial shipping trial: a 65-tonne fuel blend of 20% upgraded CNSL-derived biofuel and 80% very-low-sulphur fuel oil (VLSFO), burned on a roundtrip voyage between Singapore and Brazil, with reported clean combustion, no injector fouling, and stable performance across engine loads — the practical bar a fuel has to clear to count as genuinely drop-in rather than requiring new engines or new bunkering infrastructure.

India's own bet, and it isn't LNG

This blog's own reporting already covers India's port-based green-fuel push in full — the National Green Hydrogen Mission's port hubs, DGS's biofuel-bunkering circular, and Kandla's April 2026 DNV-certified shore-to-ship methanol trial and Port Readiness Level 6 rating in detail; none of that is repeated here. What's new since that piece: Kandla has begun site work on what is reported as India's first 150-tonnes-a-day e-methanol plant, a partnership with Assam Petrochemicals and Thermax, and has issued tenders for a separate port-integrated biomethanol production facility, with a stated target of 500,000 tonnes of renewable methanol capacity by 2028–29 aimed at the Asia-Europe shipping corridor that already passes the port.

What doesn't follow from any of this

None of the above means IMO's framework is dead; a majority of member states rebuilding support between the October 2025 adjournment and MEPC 84 is a real, measured shift, not just diplomatic noise, and 4 December 2026 could go either way. Nor does LNG's 80% order share mean LNG is shipping's actual climate solution — it means LNG is the fuel with the infrastructure and engine supply chain ready today, which is a different claim, and the methane-slip caveat above is why. The MASH Makes-DS NORDEN trial is one voyage on one route with one 65-tonne blend; nothing here shows a supply chain exists to make cashew-shell biofuel available at bunker scale anywhere else, and this piece found no second commercial voyage using the same fuel. And Kandla's methanol trial and Port Readiness Level 6 rating describe a successful pilot, not a running bunkering business; the 500,000-tonne 2028-29 target is a stated plan, not yet a delivered plant.

What would fix this

• Publish a firm, binding date for the IMO's next vote and stick to it, rather than letting "the framework could be adopted later this year" carry across three consecutive MEPC cycles, which is what has happened since April 2025.
• Require LNG-fuelled ships to report actual measured methane slip, not modelled slip, so the EU ETS's 2026 inclusion of methane has real ship-level data to price against rather than engine-manufacturer test-bed figures.
• Publish a second, independent commercial trial of MASH Makes' or a comparable agricultural-residue biofuel before treating the Singapore-Brazil voyage as evidence the fuel is ready at scale, not just ready in principle.

These are proposals from this blog, not recommendations any agency has adopted.

Sources and caveats

About this article: Researched, written and edited by Umashankar Triplicane Dwarakanathan, with AI research assistance; every figure is meant to trace to the primary source cited. See the Editorial Policy for how sourcing, AI use and corrections work.