Re: [pct-l] Time to kick the Dead Horse once again

[Brick Robbins <brick@fastpack.com>]

I am going to take issue with some of the stuff Montedodge@aol.com posted.

> You can use
>whatever to cook with on the PCT, No big deal, but go peddle your propane
>story to the Junior High Chemistry class, you might get some takers. 

Computing the energy density (energy/weight) of hydrocarbons is pretty
tricky because the fractions vary from refinery to refinery, and gasoline
varries from season to season. Most of the numbers I found were adjusted
for engine efficiency, which doesn't count here. I dug up the numbers below
from several references. 

I'm not sure exactly what is in white gas, except that it has much more
naptha than gasoline, and I couldn't find any numbers for it. I'm not a
petro-chemist,  but here is the best I found:

Fuel   		Energy density (MJ/Kg)
*****                 *************
Hydrogen	   138
Diesel (kero)          57
Gasoline               50.4
Propane	   47-51

So Hydorgen is the best, and Kerosene (Diesel) is the best Hydrocarbon, but
Propane and Gasoline are about the same, with Propane a little less. LNG is
a mixture of several fractions (lots of methane), and is less energy dense
that pure Propane.

> F-16 fighter jets run on
>basicly superfiltered kerosene which is tops on energy per weight of all
>camping fuel followed closely by white gas. 

This is really quite misleading, since fuel density measured in
energy/volume is as important in aircraft as energy/weight. In backpacking,
energy/weight is mostly what we care about. Also combat aircraft have to
worry about leaks and exposions from combat damage as well so this analogy
doesn't apply.

If energy/weight was the only concern then F-16s would run on Hydrogen
(like the Shuttle does).

Considering volume only, Propane is about half as engery dense as kersene.
LNG is worse.

FWIW, Ive used both types of stoves, and find the propane ones easier to
use, but I cary my ancient MSR-KG when I travel because it will burn almost
anything, and I can fly on airlines with it as long as the tank is empty.

I'm gonna put on my list Admin hat and ask everyone involved in this thread
to be a little more polite.

Hike Your own Hike.

-Brick
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