[WhatsTheBigIdea]

Alternative fuel? yes.

Greenhouse gas solution? no.

Ammonia will (and does) leak into the environment where it becomes a part of the natural nitrogen cycle. The end result of the natural nitrogen cycle is N2O (aka laughing gas) which is a greenhouse gas 250-350x more powerful than CO2.

Running the world on ammonia, even if logistically possible, will likely accelerate climate change, not slow it.