asks: "I've been following the discussions in the media regarding fuel cells & hydrogen fuel. I have an idea (really a set of ideas) for handling the CO2 issues, which could make fuel cells a better solution. Perhaps someone who know about such things can tell me whether it's workable or not. Speculating wildly, if the carbon could be retained in the process (in a discharge tank, for instance), then it might even be useful as a feedstock for plastics, for example. How might a fuel cell process (both production and use), possibly multistage or incorporating a catalytic pre-process, emit carbon in non-gaseous form? What about a fuel cell that just converted ethanol or higher weight hydrocarbons to methanol, or perhaps a nitrite or another byproduct? Consumers could then recycle this waste to the fuel station at the next fill-up. Even this incomplete process can provide more energy per weight or volume than hydrogen, in theory. Would such a process be possible, or feasible?"
"Many fuels can be used in fuel cells, including hydrogen, methane/methanol, ethanol, and ammonia. One of the problems with all these, in fact any system that consumes hydrocarbons (either biomass or petroleum), is that at some point in the process the carbon is released as carbon dioxide. For H2 and NH3 the problem is in the production facility; for hydrocarbon fuels the fuel cell itself emits carbon in some form. Perhaps fuel cell research has tended to think in terms replacing the existing combustion model, with the given that output will be H2O and CO2. Is anyone studying the possibility of fuel cells that have other output chemistry?"