The American Spectator

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p> FUEL CELLS AND EXPLOSIONS br> Re: Reid Collins's Nine 9's : /p>

Although it doesn't detract from Reid Collins' excellent argument regarding reliability and why we continue to explore space, accuracy demands that I rise up from my retirement and dig back into my days as a Test Engineer on the Fuel Cell/Cryogenic Systems on the Apollo space capsule. Having personally been "responsible" for ruining three prototype fuel cells at $375,000 each during an early test run, I think I have paid my dues and know whereof I speak.

The explosion on Apollo 13 was not in a "fuel cell tank" of which there are several, but in the main oxygen tank which supplied oxygen to mix with hydrogen in the fuel cells to produce electricity and potable water. This resulted in an electrical power and oxygen shortage requiring all those inventive workarounds while the astronauts waited out their return from space.

To make such an erroneous statement as Mr. Collins has done is to suggest that fuel cells are in themselves subject to explosions and are therefore dangerous. The possibility of an explosion in a fuel cell itself is minuscule compared with the possibility of an explosion in the fuel cell's fuel tanks. Any collection of oxygen and/or hydrogen in tanks anywhere, whether it be on a spacecraft or an automobile, is dangerous. But then, so were Ford Pinto automobile gas tanks!

As an aside, one might ask where the hydrogen and oxygen that a fuel cell in an automobile would use comes from? From water, broken down by electrolysis (passing electricity through the water), just the reverse of the fuel cell's process whereby electricity and water are reclaimed from the two gasses. Now, where does the electricity come from which is used to break the water down into hydrogen and oxygen? Duh! From electrical power plants of course, burning natural gas or fuel oil, or nuclear power plants or water power or solar power or wind power.

There ain't no free lunch! I no longer know the exact figures, but roughly speaking, approximately 30% of the energy contained in crude oil can be turned into electricity, and approximately 30% of the energy contained in that electricity can be converted to hydrogen and oxygen, and approximately 30% of the energy contained in the hydrogen and oxygen can be converted back to electricity by a fuel cell, and approximately 30% of the energy contained in that electricity can be converted to mechanical energy to drive an automobile down the highway. The rest of the energy is wasted as heat.

Others are invited to suggest more accurate percentages than I have used, but even if we are most generous and allow that 80% efficiency in each of the above-listed conversions is more accurate, we still have 0.8 X 0.8 X 0.8 X 0.8 = 0.4096, which equals 41% conversion efficiency. I wonder how that compares with the efficiency of an internal combustion engine? (Again, one of your readers probably knows the answer so I won't bother to research it.)

p>Of course, all the pollution in the fuel cell sequence comes at the electrical power plant stage, assuming either natural gas or oil, so that's an advantage of burning hydrogen and oxygen in an automobile. Energy conservation, however, isn't one. We are still going to have to build more nuclear power plants, or start drilling in Alaska some day. br> -- Bob Johnson

topics:
Military, NATO, Energy, Alaska, Oil