G.R. Patterson III wrote:


wrote:

Makes one wonder what the overall efficiency is versus just burning the
diesel.

If you go back and read my post, you'll see that the vehicles travel three times
as far on a tank of fuel as they do with a conventional engine. That's what "fuel
consumption is about one-third of what the same vehicle uses with a diesel engine"
means.

George Patterson
Great discoveries are not announced with "Eureka!". What's usually said is
"Hummmmm... That's interesting...."

I found the AP story and the whole thing smells of inept reporting.

From the story:

"Fuel cell technology takes a regular fuel and pulls off its hydrogen
molecules, which are stored as gas. The electrons from the hydrogen then
power a battery."

So what have they really built here, a true fuel cell that runs on diesel
or a hydrogen generator that feeds a hydrogen fuel cell? My guess is that
it is a hydrogen generator.

From the story:

"For example, the Stryker infantry transports use a hybrid engine that runs
on fuel cell power or combusted fuel."

So is this a conventional engine that runs on either diesel or hydrogen or
is it a diesel engine supplemented with an electric motor?

From the story:

"But with a fuel cell, a truck with a given amount of diesel can run three
times the usual distance,..."

This one is really hard to swallow.

To triple the efficiency, keeping engine power output equal, means the
original engine/fuel combination has to have an efficiency of less than
33%.

Conventional diesel engines are already much better then that while
fuel cell efficiencies are stuggling to get much better than 50%.

It is also hard to see how you are going to get 3 times the energy out
of a fuel when you throw away a portion of the potential energy, i.e.
the carbon.

I think the AP guy that did this report got his training at CBS news.

In an attempt to find some real facts, I found the following:

www.dtic.mil mentions an Army hybrid electric vehicle project that
"will integrate a proton exchange membrane fuel cell with a fuel reformer
that can reform JP-8 fuel...".

Unfortunately there are few details.

A search of the Auburn site has lots of stuff about fuel cells to replace
battery systems but nothing that seems to relate to the breathless AP
story.

So unless someone here has an "in" at the Anniston Army Depot or Auburn,
I guess we have to wait for a competent reporter.

--
Jim Pennino

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