How will exhaust from Hydrogen powered cars impact our roads?

[QUOTE=Mangetout]
In many parts of the world, actual liquid water naturally falls from the sky with some regularity, but fails in most cases to cause massive disruption to traffic or infrastructure.
The amount of water being expelled from the exhausts of hydrogen powered cars cannot possibly exceed the sort of amounts that fall as rain during a gentle shower - and I suspect they fall short of that amount by orders of magnitude. Of course it might have some effect, but I don’t think it’s going to be a gross measurable one.
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Well, you weren’t on 616 South this past Wednesday then. 'Cause freezing water on the road had me stopped for over two hours. And guess what? In the winter it isn’t even *that *uncommon here in PA.

[QUOTE=Q.E.D.]
Because water weighs nine times more than the hydrogen that was burned to produce it. That would make a not-insignificant dent in your fuel economy.
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I wonder if we should worry about oxygen shortages, then. :slight_smile:

Actually, how much oxygen by weight is used in the current conversion process?

I don’t know how so much hydrogen would be produced commercially. From water via electrolysis? Kind of evens out the oxygen worry.

[QUOTE=Balthisar]
I don’t know how so much hydrogen would be produced commercially. From water via electrolysis? Kind of evens out the oxygen worry.
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The cheapest way to produce hydrogen is from natural gas. Kind of ironic that the fuel of the future will likely come from fossil fuel until prices rise considerably.

[QUOTE=Balthisar]
I wonder if we should worry about oxygen shortages, then. :slight_smile:

Actually, how much oxygen by weight is used in the current conversion process?

I don’t know how so much hydrogen would be produced commercially. From water via electrolysis? Kind of evens out the oxygen worry.
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I make it that 25 atoms of oxygen are used to burn one molecule of octane - that’s 400 parts by weight of oxygen to 114 parts by weight of octane. So the oxygen weighs not quite four times as much as the gas.

Try collecting steam from your kettle sometime and see how long it takes you to fill a glass.

Your hydogen car will (well, if we ever have them) produce substantially less than a quart of water per mile. You’d need massive traffic density to produce so much as a puddle on the road.