Quote Originally Posted by purplehaze11
do they emit water of water vapor? if it is just water vapor then it seems like far less would be able to freeze into ice.

I'm pretty sure that in cold weather, water vapor would still plummet to the ground before getting very high. But...


Well... the burning of gasoline (or alcohol) also emits water vapor together with the CO2. And, for a given amount of energy generated, the burning of gasoline emits more water vapor than the burning of hydrogen.
The burning of hydrogen generates far more energy than gasoline, so less of it is needed to generate the same amount of energy, and so less water vapor is produced.
So, if this problem does not happens with normal cars, it also wont happen with hydrogen fueled cars.

I should have known some physicist would come along and save the day! :jointsmile: Much thanks for the help Coelho.



EDIT: BTW, isn't Brazil the country that's converted 85% of it's car fuel to sugar-cane bio-diesel? How's that working out?