Comment by smaudet
Sibling commenters mention industrial uses, sustainability means far more than just cars or electricity, part of why the focus on electric/cars is so short-sighted (never mind the issues electricity distribution brings to the table)...
But for cars/electricity, this is potentially excellent news (assuming longevity and cost of the operating equipment). The distribution costs are much lower than Hydrogen, and it could be used easily to power existing Hydrogen fleets. I'd wager this even makes electricity distribution easier, as ammonia batteries could be relatively stable and easily distributed as well.
Ammonia is far to dangerous for cars. Household cleaning ammonia concentrate is 99% water. That is concentrate, you dilute it for use (generally 16:1), and it is still nasty stuff. No car with enough ammonia to use it for energy will be allowed in a tunnel. To work on a car that uses this for fuel will require extreme protective gear - a chemical breathing mask, and protective clothing covering the entire body. Working on machines in such gear is not easy.