Ammonia-fuelled ship engine
5-6
Technology Description
Combustion engines fuelled with ammonia could represent a carbon-free solution for ship propulsion, particularly for long-distance oceangoing merchant ships.
Ammonia is the most traded chemical commodity, so operators already have expertise in handling it. Its storage and transport infrastructure is well deployed. Ammonia is over 50% more energy-dense per unit of volume than liquid hydrogen, therefore potentially more suitable as a transport fuel than hydrogen.
It is stored at -33 °C, which is higher than the storage temperatures required for natural gas and hydrogen (-153 °C and -253 °C, respectively).
Nevertheless, challenges remain, especially related to the hard-to-ignite combustion process and a low flame speed.
Ammonia is very toxic and thus specific design and operation measures need to be implemented: confinement of machinery, tank connection spaces and fuel preparation room; double piping; leak detection; boil-off gas management system; ventilation of confinement areas; corrosion-resistant materials; layout protecting tanks in case of collision or loading/unloading accidents; special procedures and protective equipment for maintenance personnel.
Relevance for Net Zero
Ammonia is seen to be one of the most promising synthetic fuels, as it is easier to store than hydrogen. It benefits from an already existing infrastructure and distribution network (due to its industrial use, mainly for fertiliser synthesis) - which would need scaling up in the case of broad application in shipping. Internal combustion engines adapted to this fuel are one option for the use of this energy vector.
Key Countries
Japan, Denmark, Finland
Have a solution for
this technology?
List your innovation on the InCarbZero platform and increase your visibility to industry partners.