Alternatives Fuels: The Present and Future of Containment Systems and Their Impact on the Design and Construction of Ships

In recent years, driven primarily by SOx emissions regulations, there has been a move towards the adoption of Liquefied Natural Gas (LNG) as a marine fuel. More recent decarbonisation targets, and the emissions regulations that are due to follow, will almost certainly trigger a further move towards other low carbon, carbon neutral and zero carbon fuels. Methanol, ammonia, and hydrogen offer a potential pathway for the decarbonisation of the shipping industry. However, the various physical and thermodynamic properties of such alternative fuels will require new containment systems onboard ships requiring the marine industry to embrace containment technologies used in other industries or, where necessary, develop industry-specific solutions. Shipboard containment systems for diesel fuels are currently physical, based on storage at near ambient temperatures and ambient pressures and for natural gas at high pressure (compressed) or low temperature (cryogenic), or a combination of such. Future containment technologies are likely to also include material and chemical based storage, exploiting chemical processes to hydrogenate or dehydrogenate carriers, in both liquid or solid matrices. This paper provides an overview of alternative fuels and their containment technologies and the implications on ship design and construction.