Originally posted by Rictor
In theory, what happens when the water starts getting short? There isn't an infinite amount of it. Anyone know around when we could start seeing water shortages if the whole worlds accepts hydrogen fuel as the fuel of choice?
Well, 70% of the surface of the planet is covered of water. I'm pretty sure that's more than the available petrol

But anyway, you can get hydrogen in the air too, and probably in other organic materials, and in space, in the sun, on various gazeous planets, in some other rocky planets atmospheres, and even in the "vacuum" of space, but it's really scattered around. Never gonna run pout of hydrogen, or that means the end of the universe ( isn't 99% of the materials in the universe hydrogen, actually? ).