New Fuels Studies Still Require Apples with Apples Comparisons

It was back in 2022, that industry group SEA-LNG said: The industry is making newbuild investment decisions now that will impact greenhouse gas emissions today and for the next 25-30 years, the typical lifetime of a vessel. It is essential their assessments of alternative marine fuel pathways are made on a like-for-like, or “apples with apples” basis.

The issue was that discussion of alternative fuels too often compared the green versions of ammonia and methanol with fossil LNG.

The “apples with apples” analogy is still relevant today to try and make sense of the assumptions and comparisons made in the wide range of studies continuing to be published. For example:

Last week UCL published a study that concluded there is potential for LNG to take on a stepping stone role in the decarbonization of shipping fuels but only if more stringent policies drive deployment of genuinely “ammonia ready” ships. Without such safeguards, LNG investments risk becoming stranded assets that compete with, rather than enable, green ammonia. Methanol was assessed as offering even weaker stepping stone characteristics and may divert capital and political attention away from ammonia without providing durable system benefits.

SEA-LNG subsequently published its view with Steve Esau, Chief Operating Officer, saying: “The maritime energy transition is a complex topic, so while we welcome analysis which generates meaningful insights, this study is predicated on questionable assumptions. First, it states that e-ammonia is the only viable and scalable solution for maritime decarbonization. Second, it discounts the decarbonization pathways offered by methane and methanol, characterizing them as “dead-ends.

“All synthetic, or e-fuels, face a common scaling challenge, namely access to large volumes of renewable, or green hydrogen feedstock, at low cost. Green hydrogen accounts for 70%-80% of the cost of all e-fuels. A claim that a world exists in which e-ammonia is scalable while e-methane and e-methanol are not, despite drawing on the same feedstocks is difficult to justify.”

Meanwhile, a study by Canadian and Saudi Arabian researchers adds another dimension to the debate with the finding that no single fuel is consistently dominating across balanced, climate-led or cost-led perspectives. Instead, they concluded that hydrogen performs best under climate-led priorities, biodiesel dominates under cost-led conditions, and ammonia and methanol emerge as competitive options under balanced scenarios.

LNG wasn’t considered in the rankings, but they found: “Hydrogen emerges as the climate-optimal option, consistently leading under climate-led priorities and underscoring its potential role as an ultimate zero-emission fuel for international shipping. However, its competitiveness remains contingent on substantial reductions in production costs and large-scale deployment of supporting infrastructure.

“Ammonia is identified as the most resilient pathway across scenarios, ranking first in the balanced scenario and remaining competitive under both climate-led and cost-led conditions. Its scalability, tradability, and growing industrial maturity position it as a strong candidate for deep decarbonization, although safety concerns, NOx emissions, and ammonia slip remain significant barriers to widespread adoption.

“Methanol occupies a transitional middle ground, benefiting from high technological readiness and regulatory familiarity, yet constrained by its dependence on captured CO2and the parallel development of carbon capture systems.

“Biodiesel, while cost-robust and attractive under economically constrained conditions, is ultimately limited by sustainable feedstock availability and residual lifecycle emissions, restricting its long- term role in achieving deep decarbonization.”

Collectively, these results underscore that maritime decarbonization cannot be reduced to a single “winning” fuel pathway, they say.

Back in 2022, Esau’s said: “Decarbonization will not be a ‘big bang’ process where the industry moves in a single step from fossil to zero-emission, renewable fuels. It is likely to take place incrementally as fuels are gradually decarbonized through the addition of low and zero-emission drop-ins.”

Technology for hydrogen drop-ins is under development. This week, lomarlabs entered a collaboration with Blaze Energy to pilot a fuel reformer that converts ammonia, methanol, or LNG into hydrogen directly onboard the ship, allowing propulsion and power generation machinery and equipment to efficiently operate on full or partial hydrogen blends.

Stylianos Papageorgiou, Managing Director of lomarlabs, said: “The energy transition in shipping will be non-linear, and multi-fuel for longer than we may want or expect. Technologies that create optionality, rather than betting on a single outcome, will be strategically important.”