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Had a chat with my Brother's FIL,a retired aero engineer who was interested on hearing about me having a Zoe..the subject moved on to hydrogen cars and he raised a valid point..if a fuel cell car main output is a little water from the tailpipe,what happens if there were to be many of them on the road in freezing conditions?
 

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Had a chat with my Brother's FIL,a retired aero engineer who was interested on hearing about me having a Zoe..the subject moved on to hydrogen cars and he raised a valid point..if a fuel cell car main output is a little water from the tailpipe,what happens if there were to be many of them on the road in freezing conditions?
Guess we will get water tanks fitted, that need to be drained at home ....
 

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We know they carry ~5kgs of hydrogen to go "300 miles" (200 miles) someone better than me at chemistry can tell you the exact volume of water that can be created from 5kgs of hydrogen, but I don't think it could be more than 10kgs, so 10L. Spread across 200 miles that's not very much.
 

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That's 5kg of compressed liquid hydrogen. It might expand to hundreds of cubic metres of gaseous matter, but we don't know how it compares to a cloud in the sky, that drops rain...
Again, my chemistry is not great, but two H molecules combine with one O to create water, so as a guess I'm saying the O weighs the same as 2 H, and gives us 10kgs of water.
 
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Again, my chemistry is not great, but two H molecules combine with one O to create water, so as a guess I'm saying the O weighs the same as 2 H, and gives us 10kgs of water.
Ooph. Atomic Mass of Hydrogen approx 1, Atomic Mass of Oxygen approx 16, so H2O molecular mass is 18, so 5kg of Hydrogen is 45kg of Water...
 

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Ooph. Atomic Mass of Hydrogen approx 1, Atomic Mass of Oxygen approx 16, so H2O molecular mass is 18, so 5kg of Hydrogen is 45kg of Water...
So that's about a cup of water per mile. Still not very much per car, but could cause hazardous black ice on roads which aren't on gritting routes.
 

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Space shuttle fuel cells stack would flood in about 30 minutes if the water didn't go somewhere. With no backup batteries, keeping the fuel cells running was important.

Normally the water would go into a tank, but some of it was jettisoned. There were heaters to stop the water from freezing and blocking the pipes.


Would be "interesting" if they early H2 vehicles had problems with exhaust icing.
 

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Ooph. Atomic Mass of Hydrogen approx 1, Atomic Mass of Oxygen approx 16, so H2O molecular mass is 18, so 5kg of Hydrogen is 45kg of Water...
Haha I said my chemistry knowledge was bad!! :p

40kgs seems like a lot of oxygen, how much oxygen would a typical ICE consume to travel the same distance?
 

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You'd think most of the oxygen going in an ice motor is going to come out the tailpipe as CO2 and H20. : shrug:

Hydrocarbon mystery.

Maybe a chemistry expert can work backwards from the carbon emissions numbers.
 

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After a bit of googling

A 1litre engine running are 1000rpm would need 299mgs of oxygen per minute to run efficiently.

Everything is linear so twice the Revs twice the oxygen needed etc.

Edit:
It's 299mgs per revolution of oxygen intake not 1000revs. Also not all O2 is converted.
 
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