Fuels move 'from pilots to practice'

Ammonia and methanol are now ready for their next stage of deployment in shipping

By Carly Fields

Pitted as fuels of the future for shipping, methanol and ammonia are now ready to move from the experimental stage to widespread adoption. But while the technological readiness is there, the journey ahead is "a marathon, not a sprint”, according to a report from the Global Maritime Forum, with significant hurdles to clear, particularly in the development of a robust fuel supply chain. 

The transition from pilot programs to practical, large-scale implementation is already proving to be a complex, multi-faceted challenge that requires unprecedented collaboration across the entire value chain—from fuel producers and ports to shipowners and policymakers. The stakes are high, as the industry races to meet its ambitious decarbonisation targets.

The GMF report, entitled ‘From pilots to practice: Methanol and ammonia as shipping fuels’, highlights a significant leap in maturity for both fuel types since 2020. Methanol, already past its "proof of concept" phase, is now entering "initial scale”. With around 60 methanol-capable vessels on the water and more than 300 more on order, the industry is witnessing a tangible shift in its investment patterns. 

Early adopters, report GMF, are finding methanol relatively easy to adopt, largely due to its liquid state at ambient temperatures and pressures, and the availability of key components such as engines and bunkering equipment that can be retrofitted or installed with manageable modifications.

However, one of the main challenges for methanol's continued maturation is the scarcity of green molecules, which are currently costly and difficult to procure. The economic viability of methanol-powered fleets hinges on a reliable, affordable supply of green methanol, a challenge that requires significant investment in renewable energy and production facilities. This supply-side barrier is a major bottleneck that must be addressed to ensure methanol can truly scale.

"It is clear that both fuels require a concerted push if they are to be able to rapidly scale from around 2030 in line with the industry's decarbonisation targets," the report finds. This push, according to early movers, must be a mix of policy incentives, harmonised certification, and deep collaboration across the value chain. Without these interventions, the report suggests, the inherent cost disparity between fossil fuels and their green alternatives will slow adoption, potentially jeopardising the industry’s climate goals. The onus is on governments and international bodies to create a level playing field and de-risk the massive investments required for this transition.

Ammonia moves

Meanwhile, ammonia is "rapidly approaching proof of concept" as a viable shipping fuel. The report notes that engine tests are nearing completion, and bunkering trials are successfully underway at major ports, a critical step towards proving its operational feasibility. 

Due to its toxic nature, however, ammonia requires significant and expensive design changes to ships, including "segregating sections for leak safety and no venting under any circumstances emerging as guiding design principles”,” said the report. This also requires careful training of crews and robust safety protocols to mitigate the risks associated with handling the fuel.

A major breakthrough has been the progress on emissions. While ammonia can produce nitrous oxide and ammonia slip when burned, results from full-scale engine tests suggest that operating on ammonia could reduce a ship's tank-to-wake emissions by "90 and 95%”. This, the report says, "exceeds the leading engine designers' own initial expectations and targets”. This performance is a significant victory for the fuel, positioning it as a powerful contender in the race for true zero-emission shipping. 

However, interviewees are quick to point out that adoption will be gradual, with initial ships only using ammonia 25% to 50% of the time, operating on dual-fuel engines that can switch to conventional fuels. This phased approach will allow the industry to gain operational experience and build confidence while the supply chain matures, before making a full commitment to ammonia as a primary fuel source.

For ammonia, bunkering is currently the "weakest link”, says the report. While trials have been successful, a key gap remains in the necessary infrastructure. There's a poor investment case for bunker vessels, which are expensive assets that rely on high levels of utilisation that are not yet available. This creates a classic chicken-and-egg problem: no one wants to build bunker vessels until there are enough ships to service, but no one wants to order ammonia-fuelled ships until they are confident the bunkering infrastructure will be in place. 

This has led to recommendations for a mix of fuel demand aggregation and capital expenditure grants for bunkering infrastructure to lower the threshold for investment. Demand aggregation, in particular, could see multiple companies pool their fuel needs to create a sufficient market signal to justify the construction of these vital vessels. 

Setting the roadmap

The report's recommendations offer a clear roadmap for the industry. To accelerate the development of the fuel supply chain, it calls for action to "provide policy incentives to reduce the cost gap facing the fuels”, "establish robust, harmonised fuel certification”, and "operationalise fuel demand aggregation to provide the level of utilisation needed to justify investments in bunkering infrastructure”. This framework aims to tackle the economic and regulatory barriers head-on, creating a more attractive environment for investment in new fuel technologies. 

On the technology and design front, the report suggests a need to "close gaps in the availability of methanol and ammonia engine sizes and types”, "undertake independent studies to measure the real-world emissions from the first wave of commercial ammonia-powered vessels”, and "enhance knowledge sharing" across the sector. These actions are crucial for refining the technology and ensuring that its real-world performance lives up to its promise.

"Pursue deeper collaboration between ports, terminals, and early movers through green corridor initiatives, route-based feasibility studies, and/or collaborative bunkering demonstrations”, is a key recommendation. This concerted action, from policy makers to ports and shipowners, is seen as essential to propel these fuels to the scale needed to meet the industry’s ambitious decarbonisation targets. 

The technology is no longer the main barrier; the focus has now squarely shifted to the supply chain. The coming years will be a test of the industry's ability to work together to overcome logistical, economic, and regulatory challenges. Success will not only secure a sustainable future for shipping but also provide a case study for decarbonisation across other hard-to-abate sectors.