[RedDevil]

Raise from the dead, ye olde thread!
While ammonia has a lot of potential as a fuel, the primary problem is that its production is relatively inefficient.

Or should I say, was...
https://cleantechnica.com/2019/03/22...ity-of-aarhus/

“We have a particularly effective technology here at Foulum [Denmark] that enables us to make ammonia exclusively from electricity from certified wind turbines, water and air. The method is far more energy-efficient than conventional ammonia production, which today accounts for as much as 1% of the world’s total energy consumption.”

It can now effectively be used in cars like this ammonia powered Toyota Mirai.
Forget plain hydrogen - ammonia is the future?


Ammonia is also dense enough to be practical as a shipping fuel. Cool it below -40 degrees, then it won't boil under atmospheric pressure; a ships ammonia tank would need an insulating layer, but that's not prohibitive.

But even if it wouldn't find its way as a fuel, if only the 1% of global energy consumption needed to produce it for current purposes (fertilizer, paint, chemical processing, ...) can go down substantially that already is a big thing.