[FractalParadigm]

> But where I live, winters could be a big issue. These vehicles could coat the roads with thin black ice.

I never even considered this as a problem. Is the exhaust liquid water though? Because my understanding of the process is such that is still creates an appreciable amount of heat, causing the exhaust to leave as a vapour (much in the same way water vapour is already expelled from catalyzed ICE exhaust, or people breathing).

[p_j_w]

I've seen a Mirai release a small amount of liquid water before. It could indeed be an issue.