I pulled this article from the Motley fool
Warning: this is a very long post, but, maybe worth your reading if you are not a
FC expert.
Hi Fools,
In the spirit of Foolishness, first let me tell you something about myself: I am a
graduate student majoring in electrochemistry. My research topic is on
development of electrocatalysts for fuel cells. You guessed it, I am betting my
career on it.
As most of you know by now that fuel cells are the engine of the future for
power generation. It has many desirable features, e.g., more efficient, quieter
and cleaner than existing IC engines.
From what I have read here on this and other boards I got the impression that
the Fools have been misled by the media to have foolish expectations on the time
scale for the commercialization of FC vehicles and household FC units.
Have you ever noticed the conspicuous absence of the cost of highly publicized
FC cars (NECAR 4 of DaimlerChrysler) or the cost of fuel processors (by Epyx
used in PlugPower FC) from those media articles ?
In my opinion, it will probably take another 10-20 years to produce the FC
vehicles, you and I or any other average consumer could afford. The problem
has been and will the initial and maintenance COST of FCs as opposed to the
existing options we use everyday or other alternatives.
The detailed reasons:
IC engines run on high temperature processes, that is, explosive combustion, no
catalyst is required to carry out the reaction to push the piston in IC engines.
Due to this high temp, the IC engines are less susceptible to minute impurities in
the reactants (gasoline or natural gas), and hence is very reliable. However,
excess heat is rejected as a waste to the environment (Carnot cycle limitations),
therefore IC engines are less efficient, 25-30%, apart from being noisy and
polluting. FCs are >60% efficient if pure hydrogen used.
FC runs at low temperature with minimal or no excess heat rejection and
precisely because of that they are more efficient in extracting the energy from the
oxidation reaction of the fuels. However, FC reactions require catalysts to run
sufficiently fast enough (power that is ) to be useful in practice.,
The problem with FC catalysts is that they are prone to poisoning even in the
presence of 10 parts per million carbon monoxide (10ppm CO) which is
cogenerated during the reformation of gasoline or other organic fuels like
methane, methanol and ethanol. Hence, the reformate hydrogen gas mixture has
to be purified before being fed to FC. The unfortunate thing the mother Nature
has thrown on us scientists is that the efficient and reliable separation of
hydrogen at those medium temperatures of the reformate process (~300
Celsius), requires the use of membranes made of noble metals and or their
alloys,, e.g., platinum, palladium(more expensive than gold) , silver etc.. Of
course other means of hydrogen gas separation, being a century old subject,
exists but they are slow or energy intensive. What this means for the FC that use
organic fuel is that the fuel processor is one extra expensive component.
Furthermore, if there is sulfur in the organic fuel, as in the case of gasoline which
we use everyday , the hydrogen separation membrane gets poisoned by the
sulfur, which means the gasoline from the gas station ,out there, can not be used
directly. If I remember it right, the Epyx reformer used in the much heralded
PlugPower fuel cell system (this past spring?) was tested with gasoline free from
sulfur. To remove the minute amount of sulfur from the gasoline is not a cheap
process. This will surely increase the cost of the reformer.
Also, there is this reliability problem even for hydrogen separation membranes,
apart from the reliability problem of FC catalyst which is even more sensitive to
impurities in the fuels than the membranes. These two processes combined, one
very efficient and the other inefficient will not make reformate/FC system any
more attractive than the existing options and other alternatives, e.g., zinc/air fuel
cells. I doubt very much PlugPower can deliver that 7kW household FC unit for
5000$ (?) in the next 2 or 3 years.
Now wonder, DaimlerChrysler put the reformate/FC in the back burner and
chose to use liquid hydrogen in its NECAR4. I believe that is what Ballard is
doing.
However, the infrastructure for hydrogen distribution either in liquid or in
gaseous form is virtually non-existent, and the cost of building it is enormous, 20
billion dollars for the US alone by some estimates. Furthermore, hydrogen is not
quite safe to handle when liquid or gas. The only hope is some kind storage of
hydrogen in an imbedded state, like in metal hydride or hydrogen absorbing
carbon nanotubes. But the progress on this front is piecemeal, no breakthrough
has come out from the past 2 decade's intensive research world over.
IMHO, the average consumer will not be able to afford an FC vehicle or a
household unit by 2010, unless we see a price increase in gasoline by a factor of
10 or some magic happens for the catalysts cost and stability and or we could
produce the precious metals by Alchemy!
For more genuine news, read the following excerpts and dig your own news and
then come to your own conclusions.
---------------------------------------------------
Hydrogen & Fuel Cell Letter, published by Peter Hoffman, an important source
of info on FC for the past 15 years. Visit the home page of this news letter at
mhv.net
H&FCL, April '99 vol. XIV/No. 3
page1:
"DaimlerChrysler Unveils Liquid-Hydrogen NECAR 4 In US, Reaffirms 2004
Launch Date
.................
One immediate goal is to reduce weight. The NECAR 4 weighs 1580 kg or
3476 lbs. By comparison the standard diesel A-class weighs 1120 kg, or 2464
lbs., Panik told F&HCL. The goal is to reduce the weight by 300 kg (663 lbs.).
Cost Reduction, Infrastructure Are Issues
Another pressing target is cost reduction. A mass produced fuel cell car would
cost $30,000 for fuel cell hardware alone. Current internal combustion engines
cost about $3,000, the company said."
On reformers by Epyx which were used in PlugPower's FCs:
page 7: Jeff Bentley, COO of Epyx, Cambridge, MA. "we can have hydrogen
with CO under 1% in 10 minutes, how we are going to get to 10 seconds is the
subject of the next 5 years of research probably."
10 ppm CO in hydrogen can significantly decrease the power of an PEMFC
within a short period of time. 10 ppm CO is 10/1,000,000 = 1/100,000 =
0.001% CO. Think for a second what would 1% CO in hydrogen can do to a
PEMFC, it kills the PEMFC in no time.
--------------------------------------------------
CHEMICAL & ENGINEERING NEWS
June 14. 1999, page 31
Fuel Cells Heading For Sale
by Mitch Jacoby
........................
"The ride (in fuel cell buses) may be smooth but passengers might get jolted if
they take a look at the price tag. According to Chicago Transit Authority, the
three Ballard-fuel cell buses cost $1.4 million each. Spare parts, maintenance,
training , related costs are expected to reach an additional $1.6 million. For
hydrogen and hydrogen filling station, the transit authority laid out roughly
another $1 million."
So to operate 3 buses, CTA has to shell out 3x1,400,000 + 1,600,000 +
1,000,000 = $6.2 million !
How much would it cost to operate 3 diesel buses ? Probably 1/10 of that
amount for fuel cell. No wonder other transit authorities are not gobbling up the
FC busses.
-------------------------------------------------
CHEMICAL & ENGINEERING NEWS
July 12, 1999
LETTERS section: PEMFC = proton exchange membrane fuel cell
"Cost continues to be the major obstacles to large scale commercialization of
fuel cell technology. For example, the target cost for an automobile PEMFC
system is $50 per kW, but the current cost is $3000 per kW."
"Most articles in news magazines on fuel cells tend to gloss over major
problems, such as that mentioned above, and produce false expectations. In a
recent article on fuel cells, and subsequent comments, I tried to give a more
realistic assessment of the technologies based on the pros and cons
[CHEMICAL ENGINEERING PROGRESS, Vol. 95-3, page 59 and Vol.
95-6, page 8,9, (1999)].
"As mentioned in my articles in CHEMICAL ENGINEERING PROGRESS,
there does not seem to be any demand for fuel cells in the developed world, in
the near term, because of cheap and plentiful conventional energy." R. Singh,
Amherst MA.
Here, a brick-mortar man of fuel cells, the people who actually construct the
stuff speaking about the reality of this marvelous technology in a peer reviewed
professional journal as opposed to journalist articles.
You get the idea.
Any criticism is welcome.
Foolishly,
Realist99.
P |
