Slashdot Mirror
US Army Pursues Hydrogen Fuel Concepts
securitas writes "According to GlobeTechnology/AP, the US Army is excited about the potential of hydrogen-powered tanks. The interest is the result of a technology demonstration that took place at Auburn University in December. Scientists have invented a process that removes the carbon and sulfur from hydrocarbon fuels like oil and gasoline. Hydrogen-powered vehicles could go three times farther than diesel-powered counterparts. DoD officials say 'it costs about $40 to move one gallon of diesel fuel from Kuwait to Baghdad.' The new process could let them take advantage of the existing oil industry infrastructure. Auburn University scientists 'realized there is already a lot of hydrogen in hydrocarbon fuel' and 'took jet fuel, which is very similar to diesel, and catalytically converted it, separating out the sulfur, carbon dioxide and carbon monoxide, and the fuel cell ran.' The Auburn team is now pursuing military funding."
The nice thing about hydrogen is that you can make it from many different energy-producing processes and ship it fairly easily.
Actually, one of the big obstacles to using hydrogen as a fuel is that it ISN'T very easily transportable. As a gas, you have to employ very high pressures that involve expensive tanks. Compress it all the way to a liquid and you've burned up so much energy that its no longer attractive as a more efficient source. Chemical storage (metal hydrides, etc) is being researched, but AFAIK, it isn't ready to be main-streamed.
We *should* be looking into efficient industrial-sized water electrolysis, or maybe some kind of thermolytic or photolytic process.
That's a great plan, except that the energy to do those things has to come from somewhere. It can't be hydrogen, because it would take more hydrogen than you are making to do it.
The wind, wave, and solar power installations that some think will save the world can easily drive an electrolytic converter, for example, and the only byproduct is oxygen.
Let's be clear about what we're talking about. I'm not sure how much hydrogen you are planning on making (total replacement of hydrocarbon fuels?) but you will have to build enough solar/wind/wave/hydro/whatever installations to nearly match the amount of energy being produced by hydrocarbons for whatever application you are interested in. The "nearly" shows up because hydrogen power IS generally more efficient than hydrocarbon based power. This is a nice theoretical solution, but practically it would be very expensive and difficult, even if it is possible.
So the air is actually *better* downwind of an electrolytic hydrogen plant (if they don't bottle all the oxygen and sell that too), and the system is closed and fully recycling, since burning the hydrogen gives you the water back.
A lot of people consider water vapor to be a green house gas.