In the future, from about 2050 onward, the world shipping fleet will likely be powered by ammonia and hydrogen, says the International Energy Agency.
The IEA report, Technology Energy Perspectives 2020, notes that, “shipping is the least energy-intensive way to carry goods: despite the size of its share of total freight transport activity, it is responsible for about one fifth of the energy used for freight transport and just 8% of total transport energy use”.
Nonetheless, shipping, like many sectors, is now reducing its carbon dioxide emissions.
In the near term, as older ships are phased-out of the world fleet and new ships are phased-in as part of the ongoing process of fleet-renewal, heavy-fuel oil will give way to distillate fuels and liquefied natural gas, the IEA says. Blending with biofuel will be increasingly used too.
In the medium term, the use of biofuel “jumps from negligible levels” to about one-fifth of total energy use in shipping. Blending with biofuels will increasingly happen from about 2025 onwards, the IEA says, adding that conventional residual fuel will be displaced.
In the longer term, biomass-to-liquids will make a large scale-contribution from about 2050.
However, at the same time, ammonia and hydrogen will come “increasingly to the fore,” especially as fossil/biofuel-fuelled ships reach the end of their life.
Ammonia and hydrogen will be used on over 60% of new vessels sold after 2060, the IEA says. By 2070, oil and gas are responsible for only one-sixth of total shipping fuel consumption.