All about methanol: your questions answered

All about methanol: your questions answered

May. 17 2023 - 4 min


As shipowners consider their next moves towards decarbonizing their operations, Julien Boulland, Global Market Leader for Sustainable Shipping, answers common questions on methanol as a marine fuel.

Can methanol fuel help achieve EEDI, EEXI and CII compliance?

From a tank-to-wake perspective, methanol reduces CO2 emissions by around 10% compared to conventional fuels. It therefore offers benefits in EEDI and EEXI, and can help to achieve or exceed the required annual CII value. However, these IMO’s short-term decarbonization measures have not adopted a well-to-wake approach.

In the next phase of IMO regulations that will consider well-to-wake approach, owners will need to adopt methanol with low-emission production pathways – for example e-methanol produced from green hydrogen.

Do methanol production pathways matter in proposed EU Fit for 55 regulations?

The answer is yes and no. No because EU ETS only considers emissions from combustion – a tank-to-wake approach. Yes because FuelEU Maritime evaluates emissions in a well-to-wake approach, so methanol from low-carbon pathways such as e-methanol and bio-methanol (from waste material feedstocks) will be more favorable to compliance.

How is methanol specified as a marine fuel?

The International Organization for Standardization (ISO) is currently working on the specification of methanol, with a tentative standard scheduled for publication in 2024.

Beyond carbon – methanol and NOx reduction

As well as having a lower carbon profile, methanol also offers a reduction in other GHG emissions. For nitrogen oxides (NOx), methanol engines are Tier II compliant with no intervention or additional technology. To achieve Tier III, shipowners can also add specific NOx abatement technology to their methanol engines.

How can I account for the lower energy density of methanol fuel?

Methanol has a volumetric energy density 2.5 times lower than marine gasoil (MGO) and 1.4 times lower than liquefied natural gas (LNG). That means ships will have to carry more fuel to achieve the same level of endurance. As a ship is a constrained space, the issue of storage onboard will have to be resolved by design for new builds or retrofits.

Do we know how methanol engines compare to conventional fuel engines?

It’s a good question, but one that we can’t answer yet. The technology is simply too new; with methanol engines only in use over less than a decade the industry hasn’t had the time to collect enough return on experience.

The corrosive aspect will have to be studied, to see if any negative impact on engine machinery, causing erosion or degradation. But we can’t yet say for certain what the impact of impurities or contamination in the fuel would be on an engine’s lifespan.

Do I need to use pilot fuels with methanol in an internal combustion engine?

Yes, absolutely. Methanol has a high auto-ignition temperature, and needs at least 5% pilot fuel (in energy). Engine makers are investigating ways to reduce the amount of pilot fuel needed – to reduce cost and additional carbon emissions in turn – but pilot fuel remains a requirement.

What do I need to consider for retrofitting an engine for methanol fuel?

It’s important to know that engine manufacturers are now developing and producing conversion kits which will facilitate retrofitting projects.

However, shipowners also need to be conscious that every ship is unique and that means with any retrofit there is no one-size-fits-all solution. They will need to carefully consider if methanol is the best fuel choice for their vessel and which technology to adopt.

Is methanol suitable as a fuel for small ships?

Methanol is known to be a popular choice today for large deep-sea vessels, like container ships, bulk carriers and tankers and, also for smaller sized vessels, such as offshore wind vessels.

Small, short-sea, harbor and inland vessels can indeed consider using methanol, as bunkering can be less of an issue.

Regarding the use of methanol in fuel cells, cruise ships may use them in addition to their engine to cover onboard power needs.

Bureau Veritas has developed NR 670, classification Rules for methanol- and ethanol-fueled ships, which cover a combination of different characteristics for all types of methanol-fueled ships.

Will methanol remain a popular low carbon fuel?

While we can’t state that with total certainty, there are encouraging signs as to methanol’s potential longevity. The orderbook is full of new methanol-fueled ships of all types, from large deep-sea vessels to harbor tugs. Furthermore, green methanol production is under development, which will help secure a sustainable well-to-wake pathway for shipping. 

Do you want to find out more about methanol and the future fuel mix? You can download our alternative fuels outlook whitepaper here, or get the low-down on methanol here.