Fuel Cell Background Information

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The following link to an article on fuel cells, from Mother Earth News, was forwarded to me - and what an article it is:

Power to the People

I also find it very interesting that one of the companies mentioned in the article has recently found itself in the middle of a runup on its stock - Plug Power. Here's a link to a recent news story.

Is this truly a wave of the future? Or will the technology be co-opted by the big money and then scaled for industrial use? It seems almost too good to be true for those who are seeking a total off-grid lifestyle with a minimum of hassle and near 100% reliability.

-- Rick Cowles (rick@csamerica.com), January 18, 2000

Answers

I've been following fuel cell technology for about fifteen years, off and on.

I would follow it more closely, except that it almost seems like a CULT. I mean, what's the big woop with fuel cells?

The way the Mother Earth describes the technology leaves me thinking that they not only don't understand the concept, but they are for some reason reporting on its us in near religious ravings, filled with untruths, half truths, and seeminly, with hype.

I'm sorry to sound so cynical, but could someone please explain to me how "mining" natural gas, then running it through a generator (which is all this plug power system is, the way they are using it) to make electricity, is such a great deal? Maybe, MAYBE, it's a more efficient generator than an internal combustion engine powered generator (which uses natural gas or propane). The article says that the fuel cell is 40% efficient. I personally think this is less than impressive

As far as "reliability, efficiency, ecology and economy. We'll add one more: autonomy.", I have more questions. How reliable is it? Is it more reliable than the Grid? How efficient is it? I'd like some numbers. Even if it's 100% efficient at turning the Hydrogen into water vapor (which I doubt), is it more efficient than other forms of power generation? I have yet to see any figures to say that it is.

Ecology--I don't see this as ecologically superior. The ME article says that the only byproduct is water vapor and heat. But this is obviously not true. If you take CH4, and process it, you HAVE TO end up with some form of Carbon in addition to the water vapor. This form of Carbon is most likely either Carbon dioxide, Carbon monoxide, or some form of semi-oxidized hydrocarbon, e.g. CHOx.

I have communicate with Plug Power on a number of occassions, asking them to explain these seeming inconsistencies. All they would tell me is that they are not about to share their "trade secrets" with me! Well, Helllllooooooo!

The ONLY real, clean, environmentally superior use I am familiar with for fuel cells is to utilize the fuel cell to GENERATE hydrogen using OTHERWISE WASTED ENERGY, such as when you normally convert kinetic energy (the energy contained in a moving object, e.g. an automobile or truck) into waste heat (the heat generated by the friction between the vehicles' brake pads and drums or disks.

A fuel cell could, theoretically, utilize this "waste" energy to generate power to separate water into Hydrogen and Oxygen. Then these two gases could be recombined by the fuel cell to create electricity, which would run an electric motor to help power the vehicle.

This is how the "hybrid cars" function, only they use a battery for the storage medium rather than a fuel cell, and the electricity stored in the batteries comes from a generator, a.k.a. the electric motor running backwards. The fuel cell could allegedly convert the energy from kinetic to potential energy and back to power more efficiently and cleanly than the electric motor/generator/battery system.

But to claim that these stationary units are some kind of wonder fuel seems, to me at least, like much ado about nothing.

Further comments on the article:

I've been told by dealers in small hydroelectric generating equipment that one should figure "only" 50% efficiency for small systems, implying at least that large hydroelectric plants are higher. At 40% efficiency, these fuel cells do not "match even the best power plants on the grid".

Obviously, if the fuel cell manufacturers figure out a way to utilize waste heat (and that seems quite easy to me, at least in the wintertime), then their claim to be as efficient as "the best power plants on the grid" will be at least impressive enough to bear investigation. On the other hand, to say that "Power plants can't do anything with that heat; it just warms up the Hudson River or whatever happens to be nearby." is patently ridiculous. Do some research.

The article points out that "these plants still have to get that power to your house, and so suffer the attendant transmission losses." This is very true, and is one of the reasons I am skeptical of claims made about the efficiency of electric cars. But the article seems to be ignoring the costs of delivering the fuel to the fuel cells. I can't imagine that it is as efficient to deliver, for instance, propane, to your home than it is to deliver electricity. After all, electricity is delivered through a wire; the propane has to be brought by truck, a very inefficient delivery system indeed. Natural gas would be more efficient than a truck for delivering the fuel cell fuel, but hey--if I had natural gas, I would be happy to burn it in my furnace, forget the fuel cell!

The article claims that the fuel cell creates" power with none of the sulfur dioxide, nitrogen oxides, unburned hydrocarbons and particulates that are spewed by conventional generating plants" I submit that the cleanliness of the fuel cell will be at least in part a function of how clean the fuel it burns is. If there is sulphur in the natural gas, for instance, there will be sulphur in the exhaust of the fuel cell.

The article claims that the fuel cell will "also produce a lot less CO2 than your home furnace" especially "if you heat with oil or propane". Sorry, but make that ONLY if you heat with oil or propane, and only if you do not use propane for your fuel cell's fuel supply. The fuel cell will produce just as much carbon as your conventional gas fired heater as long as you use the same gas. Again, the carbon has to go somewhere; the fuel cell technology at this point does not change carbon into gold.

Next question: the article claims that, should the cost of the fuel cell system drop to the $4000 range, then a typical power customer woud realize a 20% savings in electricity cost. I would like to see what figures are used to make that claim. For instance, how much does the customer pay for natural gas (assuming he can even GET natural gas) How much does he pay for Propane, if he can't get natural gas? How much does he have to pay for a kwh of electricity from the grid?

It is probably true that in SOME cases, a person could realize a savings on his power bill. But I'd need to see those prices before making a judgement.

Flash: I just whipped out my calculator. A gallon of propane contains approximately 92,000 BTU's This translates to approximately 27 kilowatt hours of power. But if the propane is processed at a 40% rate of efficiency, it only equates to 10.8 kilowatt hours. Where I live, one can buy 10.8 kilowatt hours of power from Pacific Power and Light for 60cents. A gallon of propane costs 99 cents. So, as you can see, the cost for the power generated from this fuel cell would cost about 67% more than the equivalent cost of grid power.

Where this system DOES show promise, in my opinio, is for the person who would like to live far beyond the existing power lines. The cost of extending power lines is currently extremely expensive, and here in Oregon at least, rising rapidly. In addition, also here in Oregon, the PUC is allowing the power companies to discontinue their former practice of granting a new customer the first four hundred plus feet of power line, a transformer, and all the fittings to that point FOR FREE. Now, the power company grants you NOTHING free except the LAST 100 FEET OF LINE.

I hope someone can please correct me if I'm wrong; indeed, I hope I am wrong. But since Plug Power seems unwilling or unable to edify me, I suspect I am right.

Meanwhile, I'm going to revisit some land I was looking at a couple of years ago, which I didn't purchase because of their remoteness from the power lines. I am seeing it now from a very different perspective!



-- jumpoff joe (jumpoff@echoweb.net), January 19, 2000.


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