Beyond LNG: How LNG bunkering can speed up the adoption of other gaseous marine fuels

Blog Article - Sep 13, 2023

 

As the shipping industry heads for a radical energy transition, the acceptance of LNG as a marine fuel can serve as a model and the basis for a faster adoption of other gaseous marine fuels, argues Mireille Franco, TotalEnergies Marine Fuels head of HSEQ, in a paper for Gastech.

The shipping industry is under unprecedented pressure – on the one hand, regulations from the International Maritime Organisation and the European Union are pushing the sector to decarbonize fast by finding alternative cleaner fuels. On the other, ever-expanding global trade is demanding more shipping, which needs more fuel. 

For the first time in its long history, shipping will need to focus on multiple ways of fuelling vessels with several fuel solutions and innovations rather than making do with, literally, the bottom of the oil barrel.

In such rapidly changing circumstances with their inherent uncertainties, there is one successful case study that not only proves we have the willingness and capability to make this transition work but is already serving as a foundation from which to launch other gaseous marine fuels. That is the adoption of LNG bunkering. 

Following the launch of the first commercial LNG-fuelled ship in 2000, a Norwegian ferry called GLUTRA, the use of marine LNG has not only spread geographically but also across vessel types.

There are around 350 LNG-fuelled vessels currently in operation and according to DNV data that number could rise to over 800 by 2025. LNG-fuelled vessels have particularly taken hold in the container shipping sector, where major players CMA CGM, Mediterranean Shipping Co. (MSC) and Hapag Lloyd have made significant investments in new builds.

But how did LNG bunkering gain such confidence? Through a painstaking process of rigorous studies, engine and specific equipment development, creation of regulations and standards undertaken by multiple parties in the industry including classification societies, ship owners, training organisations, harbours and seafaring crews. 

In essence, there was a soft but full industry change.
 

Ammonia: Promising but challenging

Among future fuels, one that is catching significant attention is ammonia, seen today as the biggest potential competitor to LNG as a gaseous marine fuel and the most efficient way for transporting the H2 molecule.

Ammonia is a carbon-free molecule by nature (NH₃) and easily stored under pressure or refrigerated at ambient pressures.

However, the current commercial production of ammonia involves steam methane reforming, a process which consumes a huge amount of energy. This makes ammonia a higher emitter of greenhouse gases compared to conventional marine fuel, when calculating emissions using the “well to wake” whole lifecycle method. This fact has led to numerous pilot schemes and trials to produce green ammonia.

A second major challenge, also being addressed, is a new engine design specifically for ammonia fuel. Here, we had good news last month when Copenhagen-based MAN Energy Solutions announced it had successfully completed running a test engine, its MAN B&W two-stroke 4T50ME-X type, on ammonia. Other companies are working on ammonia engines too and we expect one to come to market next year.

 

Learnings from LNG Bunkering

Our experience of creating a viable LNG bunkering sector from scratch in just a decade can help us find the solutions to many of the remaining challenges of adopting ammonia as a marine fuel.

LNG bunkering first began on board LNG carriers themselves, as a way of using the boil off gas generated by the cargo. Ammonia is, too, transported on specific carriers so this model could be used to kickstart ammonia bunkering. For LNG, the convenience of this solution led to the development of specific engines, equipment and safety measures dealing with LNG as a fuel rather than cargo.

Similar challenges in ammonia are now being addressed by different working groups, associations and coalitions. One such project was led by the Singapore-based Global Centre for Maritime Decarbonisation (GCMD) who, together with DNV, conducted an ammonia bunkering pilot safety study to pave the way for ammonia trials to take place at the world’s busiest bunkering hub.

Interestingly, the GCMD wrote in its April 2023 report that the study drew “upon existing industry practices for LNG bunkering, adapting them for ammonia bunkering”.

Another big takeaway from LNG adoption is the so-called “methane slip”, which dampened some of the euphoria about the progress made with decarbonization using LNG. It is likely that we will see “ammonia slip” but “forewarned is forearmed” and we will tackle this issue to ensure the acceptance and further development of the product.

Finally, there are many considerations around equipment design and safety where our experience with LNG has informed the current thinking about ammonia. Many issues that have been raised are framed as a “change compared to LNG” issue such as those arising from suggestions to incorporate LNG bunkering practices into ammonia bunkering operations.

Sufficient supply

Today, the base case understanding is that ammonia supply, in practical terms, should look similar to the LNG supply chain: namely ships will bring huge volumes from production sites to storage terminals, from where trucks and smaller vessels will run the last mile delivery.

Even here, there is a challenge: As ammonia’s energy density is less than conventional fuels, the volume required for storing the same amount of energy is double compared to LNG and almost three times that of conventional fuels. This will impact both the number and sizes of storage sites, engine design and the practicalities of shipping running on ammonia – perhaps more frequent fuelling stops.

Despite these numerous challenges to ammonia, it is seen as the one of the best candidates for becoming a key alternative marine fuel in the long term. The International Energy Association (IEA), in its groundbreaking 2021 report Net-Zero By 2050, said ammonia should account for a staggering half of total global marine fuel demand by 2050.

There is no doubt we stand at the precipice of a radical energy transition – but when we break down this long journey into small steps and tackle each problem on its own, I believe it is entirely possible and necessary.