This past six weeks or so has been an intense ENERGY period
for me. Hence, I beg your forgiveness for being unable to write
about any other subject. I promise this will be the last on energy
for at least a couple weeks or so. I”ve been working virtually
night and day preparing material for a 4-day course on batteries,
other energy storage and generation devices such as fuel cells. I
discussed a bit about the latter a couple weeks ago in my column
that also lamented the passing of my friend Charlie. I want to
correct one statement made in that column. Specifically, I cited
my home”s electricity usage at 25 kilowatt-hours per month.
Would that were the case. It should have been 25 kilowatt-hours
per day! This also changes my calculation of how many such
homes could be powered by a 250-kilowatt fuel cell. It”s about
240, not 7,000! This is my second mea culpa in two weeks and
probably indicates something about my own energy level.
My two colleagues, Al and Tom, and I presented the course last
week at a U. S. Navy facility in southwestern Indiana. I had
forgotten (a) how beautiful the rolling hills of that area are with
thousands of dogwoods blooming and (b) how friendly and
genuine the people are. For the course, I had the task of
delivering the lecture on fuel cells. I have had no experience with
fuel cells and it took some degree of chutzpah to talk about this
subject. To be honest, my column of a couple weeks ago was to
help embed in my mind some of the features of these devices. I
prefaced my Navy talk by saying that, ironically, I had never even
seen a fuel cell but that, after my lecture, I was to be shown one
that they had running just a short walk from our lecture hall! It
was consoling that one member of the group, prior to my lecture,
had asked me just what a fuel cell was; at least some of the
audience were indeed unfamiliar with the concept.
Well, this fuel cell installation proved to be quite impressive and
was, coincidentally, a 250-kilowatt unit. However, it was not the
phosphoric acid type of fuel cell made by ONSI, the company
mentioned in the column two weeks ago. Instead, it used a
polymer electrolyte or so-called “proton exchange” membrane
(PEM) and was manufactured by Ballard Power Systems in
Canada. This type of cell employs a membrane, a sheet of plastic
a few thousandths of an inch thick. The membrane allows
hydrogen ions (protons) to zip through it and replaces the
conventional liquid electrolytes such as the sulfuric acid in your
car battery. It”s rather neat in that each side of the sheet of
polymer is coated with platinum particles acting as the catalysts to
speed the overall reaction of hydrogen and oxygen to form water.
I think it”s neat because you have all the action taking place on
one sheet of material. Incidentally, Ballard is the company that
manufactures the fuel cells used in the fuel cell-powered buses
now running on regularly scheduled routes in Chicago and
Vancouver.
The Ballard unit I saw occupied about the same volume and
somewhat resembled the back end of your typical large tractor-
trailer. The unit was operating on natural gas that was being
compressed to a higher pressure than what comes out of your gas
line. The compressed gas then passes through a unit that removes
any sulfur that is present as an impurity in natural gas. Any
sulfur would quickly poison our platinum catalyst. The sulfur-
free gas now has to be “reformed” into a mixture rich in hydrogen
by reacting with very hot steam. This generates a good bit of
carbon monoxide, which is a poison, not only for us but also for
the platinum. So, another couple of steps involving more
catalysts “shift” the carbon monoxide to carbon dioxide, a more
acceptable compound. Only after all these steps is the hydrogen-
rich gas fed into the fuel cell. The amount of plumbing packed
into the unit to accomplish all this was quite impressive to say the
least. The unit was housed in a tent with a cooling unit sticking
outside the tent. The cooling unit was pretty noisy but inside the
tent, it was quiet.
I asked the young man in charge how often they shut down the
unit for maintenance. He replied that the unit made that decision
for them. So far, it seems that there has been no problem with the
actual fuel cell stack itself. The problems have all been with the
equipment necessary to get the gas into the proper form to feed
the fuel cell itself. It seems clear that this “PEM” (proton
exchange membrane) type of fuel cell is in its early stages as far as
the economically competitive production of large-scale power is
concerned. However, I gather from the Ballard Web site that a
similar 250-kilowatt unit will be field tested in Germany.
(Germany, incidentally, leads the world in the amount of installed
wind power facilities and is also quite active in other areas of
alternative energy such as solar power.)
At the other end of the scale, Los Alamos and Motorola are
developing a very small PEM fuel cell. This fuel cell occupies
only about a square inch of area and is being considered for use in
a cellular phone. No huge amounts of plumbing, hot steam, etc.
for this device. Instead, this tiny fuel cell would be fed methanol
directly; hence the name of the Direct Methanol Fuel cell
(DMFC). The cellphone envisioned would be of the small size
currently in use and would accommodate the tiny fuel cell plus a
slot for inserting small tubes containing methanol. When you run
out of methanol, just remove the old tube and put in a new one.
No waiting to recharge your battery.
We flew home from Indiana to New Jersey via Cleveland, landing
and taking off within a few hundred yards of NASA Lewis, site of
my first job working on the ill-conceived atomic airplane. On the
flight from Cleveland to Newark, I still couldn”t escape “energy”.
Al passed me a copy of a slick publication “World Energy” he
picked up in the airport lounge. It was an issue primarily
concerned with the petroleum industry and CEOs of major oil
companies wrote most of the articles I scanned. It was quite
interesting to read their viewpoints, on the other side of the fence
from the usual environmentally oriented critics of the oil industry.
More than one of the CEOs stressed that those who maintained
that the science predicting greenhouse warming was flawed and
no action was required were barking up the wrong tree. These
CEOs, on the contrary, were stating that, even if the science is
uncertain, there had to be a sincere effort on the part of the oil
industry to address the greenhouse gas emissions problem. One
figure I recall is that slightly over a third of the greenhouse
emissions in the U. S. come from the generation of electricity.
One CEO stressed the point that it would take the cooperation of
everyone, not just the oil and power generating industries, to
bring down these emissions.
In my own household, I”m sure we could reduce substantially
those 25 kilowatt-hours consumed per day by turning off more
lights. Now if I could only convince my wife. She would
probably suggest I write shorter columns and save all that time on
the computer, which must use a few watt-hours itself.
Allen F. Bortrum
