Alternative Fuels

The push for decarbonisation in shipping is driven by multiple factors, including the Paris Agreement, the International Maritime Organisation's (IMO) goals, and by a change in public opinion, pushing investors and charterers to fasten their energy transition.

As the IMO's goal of reducing total emissions from marine shipping by 50% by 2050 creeps closer, new alternative fuels are emerging to help the industry meets this target.

While the fate, behaviour, potential hazards and impacts of oil spills are well-known, many alternative fuels are not as widely understood. 

In a series of reports drafted for the International Group of P&I Clubs Alternative Fuels Working Group, ITOPF has investigated the fate, behaviour, hazards and the possible damage and liabilities of the following alternative fuels:

• Ammonia
• Hydrogen
• Liquefied Natural Gas (LNG)
• Liquefied Petroleum Gas (LPG)
• Biofuels (FAME and HVO)
• Methanol
• Lithium-Ion Batteries

Biofuels behave in a similar way to conventional hydrocarbons, with similar mechanisms for damage such as coating and smothering of wildlife, habitats and property. However, with higher rates of biodegradation and therefore less persistence than conventional hydrocarbons, impacts to environmental and socio-economic receptors are likely to be reduced.

Gaseous alternative fuels such as ammonia, hydrogen, LNG and LPG behave very differently and are significantly less persistent in the marine environment. Instead of widespread, longer term environmental damage associated with conventional hydrocarbon spills, these fuels present acute, short term and localised ecological impacts and potentially significant health and safety risks from their hazardous properties (cryogenic damage, toxicity, flammability and explosivity). Although methanol is not gaseous at ambient conditions, it is a volatile, flammable liquid, fully miscible with water and, if not ignited, will be rapidly lost to the atmosphere from its vapours and to water through dissolution. The risks associated with lithium-ion batteries are related to possible thermal runaway if damaged, presenting fire risks and explosion as well as potential harm in surrounding areas from toxic gas.

Overall, except for biofuels, traditional oil clean up techniques are inappropriate for the alternative fuels and response focusses on detection and monitoring through modelling, remote sensing techniques, as well as prevention and control of fire. National authorities should adapt their contingency plans and preparedness programme to capture the new challenges posed by these alternative fuels, as they become more common at sea.