Too much good stuff in all these posts. No time to start to 
wade into most of it. Let's just address a small aspect:

> What sustainable source of energy is going to be used to 
> produce the
> hydrogen?

That's not the key issue. The reason that Hydrogen is 
suggested is that SOME energy carrier is needed to turn 
non-portable energy into portable energy sustainably. 
Hydrogen is not good at this. Any other alternative that I 
am aware of is worse. Any such system is called " a 
battery". We just don't think of Hydroben in those terms, 
yet. Hydrogen energy storage and recovery is arguably the 
best battery we know of, all things considered. Bob said 
it's stupid. He's correct. But all other batteries are more 
stupid. Which doesn't stop people using them.

> I'd rather use electrical energy to charge batteries than 
> waste half the
> energy producing hydrogen.

i Energy conversion to Hydrogen need not wate 50% of the 
energy. That continued claim is an unjustified assumption 
(so far in this discussion) whose basis needs documenting.
ii What energy conversion efficincy is claimed for what sort 
of batteries that is superior to Hydrogen conversion 
overall?
iii What is the cost and ebergy mass and volumetric 
densities for these other batteries. Perhaps use LiIon or 
NimH as examples as they are the leading on market 
contendors. Or Vanadium redox as an in the wings waiter.


> I don't advocate doing nothing, it's just that hydrogen 
> isn't going to be a
> solution. I also don't look for solutions to be only 
> technical, there is
> going to be a societal aspect as well regarding 
> transportation, urban
> planning, etc.

Apart from using up all the oil as we become more desperate 
and can justify the cost of doing so, have you got any other 
suggestion for a portable sustainable energy storage medium 
that will work acceptably?

So far I am not aware of any "sensible"  suggestion that 
replaces petroleum that has performance and cost that people 
are liable to find acceptable for everyday use. Hydrogen is 
the pits. Everything else seems worse. I'd be genuinely 
pleased to hear of alternatives.


        Russell

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