What ammonia has over other potential fuel alternatives is that [it] already ha[s] a global manufacturing and distribution system in place because of its widespread use as a feedstock for fertilisers. There is also a comprehensive network of ports that handle ammonia at large scale so it could become a fuel for long-distance shipping with relative ease.
In fact, the international shipping industry has already proven the feasibility of using ammonia as a fuel in their largest ocean-going container ships. MAN Energy Solutions, a designer and manufacturer of marine engines, has announced that the first ammonia engine could be in operation by early 2022. This would also open up opportunities for green fuels for trains, heavy-duty freight and perhaps even zero-carbon aviation.
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