[Gathnet] MIT work on possible improvements on Electrolysis

[Stuart D. Gathman]

On Sat, 31 Jan 2009, Jonathan Gathman wrote:

> The promise is that they don't emit pollution, just recombine hydrogen and
> oxygen into water.
> The catch is that getting the hydrogen isn't that simple.

Hydrogen is an energy storage method - not a source of energy.  (Unless 
someone finds a hydrogen well or builds a working energy positive
fusion reactor.)

How well does hydrogen work as an energy storage method?  Due to the
heavy tanks required to store it pressurized (heavy steel) or liquified
(heavy insulation - risk of explosion from constantly leaking gas
collecting), the energy density is far less than current battery technology.
Due the huge loss of energy when pressurizing or liquifying hydrogen
(remember Boyles Gas Law from high school physics), the efficiency 
of hydrogen storage is far less than current (rather inefficient) battery
technology.  You'll save energy and get better range by just charging
some batteries.

Ok, maybe the heavy tank business can be fixed?  There was some work with
storing hydrogen as metal hydrides.  Apply heat, the hydrogen is freed,
and the hydride can be reused.  This improves the energy density and
efficiency to be on a par with current batteries.  The hydride also wears
out with charge/discharge cycles like current batteries.  So just stick
with the batteries.

But wait!  We can make an order of magnitude improvement in hydrogen storage 
by using the new nano-tech wonder element - carbon.  It turns out that
you can cram more hydrogen atoms per unit volume than even liquid hydrogen
by bonding them to chains of carbon atoms.  This gives an energy density
and efficiency 10 times that of the best battery technology.  Amazingly,
this hydrogen nano sponge is liquid at room temperature.  A lightweight
unpressurized steel tank stores enough available energy to propel
a typical automobile 400 miles.  The best part is that not only is the carbon
recycled, but it also oxidizes and becomes a dioxide gas as the hydrogen burns.
This gas remains inert in the atmosphere, until it is removed to bond with
hydrogen again.  The individual atoms are recycled - the carbon carrier never
wears out.

Astoundingly, there are huge geological deposits of carbon bonded hydrogen
ready to use - with a little refining.  And ordinary plants, microbes, and
algae have been bred to harness sunlight to pull oxidized hydrogen and carbon
from the atmosphere and reduce them to create more stored energy.  This seems
to have happened naturally before to create the buried deposits.  There is no
shortage of buried deposits and many means of creating more.  But alas,
political problems complicate the use of both.

-- 
	      Stuart D. Gathman <stuart at bmsi.com>
    Business Management Systems Inc.  Phone: 703 591-0911 Fax: 703 591-6154
"Confutatis maledictis, flammis acribus addictis" - background song for
a Microsoft sponsored "Where do you want to go from here?" commercial.