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In fact, I suspect that if GM produces fuel cells at some point in time, we will see them in Europe before we see them in the United States because of the higher fuel costs there.

John Stringer, Electric Power Research Institute: The cost of electricity from nuclear plants, as I said before, depends very much on the price of capital. If the capital cost is low enough, then the electro-steel research science is less, but that is not the point. The point is that if you have a nuclear station and you are able to run at base load all the time, then the comments that you made are quite right.

However, if—and this is usually the case—the plant doesn't go on at base load all the time, the period when it isn't going at base load can be used to generate hydrogen at a low marginal cost. That is the issue, I think.

Now, how that works out for an economy requiring hydrogen in large quantities is a matter of the scenario in which you put it, but there are scenarios in which you can get very cheap hydrogen by use of marginal hours from nuclear power.

Tom Rauchfuss, University of Illinois: I have a question about what progress you have made on high-density storage of hydrogen. Are there new materials that perhaps store more hydrogen than palladium, which is maybe 1%.

James Spearot: Unlike many of the reports that are surfacing all over the world, we have not been very successful in identifying materials that absorb large amounts of hydrogen. We are still working on this particular issue. I don't want to discredit anybody's work, but we are concerned about some of the reports because we are not able to reproduce some of the work that is being done, and we are trying very hard to reproduce it.

The most positive news we have in terms of storage is some of the numbers that are currently being evaluated in prototyped, compressed-hydrogen tanks. Right now, tanks with capability of 5,000 pounds per square inch (psi) are almost validated, and tanks with a capacity of 10,000 psi are being looked at, although they are a long way from being validated. With these two technologies, you can begin to achieve 5 or 6% hydrogen storage range.

Participant: When we talk about producing energy from agricultural sources, whether it be biomass or anything else, we have to take into consideration the energy balance between growing, harvesting, and transporting these materials so that they can be converted, let's say, to ethanol. This energy balance has been negative in the past. Is there a change now?

James Spearot: I can't answer your question specifically with numbers. All I can tell you right now is that our analyses have been based on total life-cycle energy and materials costs, and based on these total life-cycle analyses, we believe that ethanol from biomass is competitive. Ethanol from cellulose is more expensive than petroleum-based energy forms today, but there is a very real reason to think that improvements can be made in cellulose processing techniques that would allow us to bring the cost of the ethanol derived from cellulose down to a competitive level.

In terms of CO2, the life-cycle analysis has said that there are benefits from utilizing ethanol derived from cellulose, and work done at Argonne supports those numbers.



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