Tom Walker wrote in a message to Roy J. Tellason:

-> Funny you should mention that,  as I did see that in a magazine a
-> while back. The machine in question got something like 20 hours of 
-> runtime on it,  compared to 3-4 hours on a standard battery.

TW> Fuel Cell technology is Increadabily expensice at the present time.

I would have guessed that to be the case.  Is it manufacturing that jacks
the price up?

TW> Coleman, The lantern People makes a Hydrogen powered fuel cell 
TW> Power pack as I rembember it was $5000 for a 3 KW unit and iyt used
TW> special exchange cartridges for the Hydrogen at some $125 for 
TW> several hours run time.

Hmm.  Only "several hours"?  That's rather expensive.  OTOH, 
that's power that's *quiet*,  as compared with a generator or whatever. 
And it's presumably easier to haul around,  too.

TW> You could of course hook up for an External Hydrogen tank but they 
TW> speckes a Very High Purity Hydrogen. And the stuff you get from the 
TW> welding supply house for HeliArc is way to dirty and could danage 
TW> the unit

I saw something on tv in the past few weeks that was talking about fuel
cells,  and hydrogen.  But I was of the impression that they could use all
sorts of "fuel".  Maybe that was earlier on,  or something? 

-> TW> For the outdoor types there are special Solar Cell arrays also
-> TW> avaiable. But when the sun goes down you need to wind up yuor work.
-> TW> :-) :-)

-> What,  you can run one off one of those but it won't charge the onboard
-> battery?

TW> Depending on the Panel you can get some charging of the battery.

One would hope so.  

TW> Again we have a comprimise between Size/Weight and how much above 
TW> operating the Laptop the Solar Panel can do as far as charging goes.

Always tradeoffs!

TW> You got me on that one, YES you can run after dark until the 
TW> batteries shut you down.

I need to look around out there,  get a handle on what's available and for
how much.  Not that I'm in the market for that sort of thing right now, 
but it'd be nice to know what's out there at least.

I read about something recently (saw it mentioned in a book I was reading)
where they mentioned a dashboard-top panel that would keep a vehicle's
battery topped off when it was sitting for a while,  and not being driven. 
Have you ever heard of this?

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