Fair enough..
I was just thinking along the angle that Hydrogen isn't really a 'fuel' as such, but more of a energy transfer medium.
Steam reforming and electrolysis all require energy, whether this be heat from combustion or electricity generation from solar or wind.
My concern is what size area would you have to devote to solar or wind to provide enough energy, to produce enough hydrogen, to support the current amount of air travel we have at the moment.
I'd hate to think what that foot print would be.
We've been lucky with fossil fuels, we just hunt for it, we don't produce it. Wheres with hydrogen, it's produced purely by the energy we put into it..
Just a thought anyway...
