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US Army Pursues Hydrogen Fuel Concepts

Posted by simoniker on from the olive-hydrogen dept.

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."

11 of 442 comments (clear)

  1. Oil? by guarddonkey · · Score: 5, Insightful

    Does it seem kind of backwards to be using Oil in the fuel cell process?

    1. Re:Oil? by Sarojin · · Score: 5, Insightful

      Not really - right now hydrogen fuel is really only useful as a container of energy, not as an energy source.

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    2. Re:Oil? by Xolotl · · Score: 5, Insightful

      It's useful as a trnasition technology, exploiting the existing infrastructure and increasing use of hydrogen engines until a critical mass is reached where it becomes economically viable to create a dedicated hydrogen distribution system. And because they use catalysts the energy cost should be small. Very clever indeed.

    3. Re:Oil? by cluckshot · · Score: 5, Informative

      The process actually has many advantages for the Military and for civilians. But first people have to quit viewing hydrogen as a fuel and see it more like a battery that they charge up. It is not a Energy Source. It is an Energy Storage Media.

      Working on such research myself for the USAF *yes military* I have learned a lot about what is going on. The process and demand for such changes is not exactly like what the media tend to report.

      The reason we burn gasoline etc is to provide the Heat Catalyzed Hydrogen for conversion to Steam when reacted with Oxygen. While the carbon provides some energy it is really for running a Steam Engine. This cycle is limited thermally to about 38% efficient of the original energy in the steam. This is functionally further limited by other factors leaving current petrol engines about 25% to 28% efficient thermally.

      The process for Cracking Hydrogen from fuel uses about 25% of the gross energy entering the process. Then the process of running a fuel cell drive eats another 15% (more or less) This leaves a potential thermal efficiency of a drive train at something close to 60%! This is more than double the current efficiency. Curiously this is not the military reason for doing this. It is but one fairly lessor factor. The military reasons for doing this have to do with issues of "Readiness" and "Dual Use."

      If you have a tank that runs this way and you have no longer use for the tank if it runs on standard engines you have a very expensive item to leave just sitting around doing nothing. But if you drive the tank using Hydrogen and produce Electric energy to drive it, the tank can just plug in and become a "Generator" for many uses after battle is done. The savings to the military here by going to such systems is about a 4 to 1 ratio in machinery that they don't have to haul around. This coupled with increased milage etc makes the process very attractive

      In Iraq this would have allowed us to just "Plug In" and have the electrical grid up and running. But this is hardly all. There are very big issues here on the weight of drive trains and also in issues such as stealth. Current engines would allow an enemy to hear the Soldiers coming for many miles.(often 20 or more miles) This system is very quiet.

      This will spin off into civilian use. The technology is going to do many things. It will make cars which are profoundly less noisy. The technology also has pollution control issues. It is essentially a clean burn for the fuel.

      There are other issues here that many people could hardly imagine. The storage of Hydrogen as a liquified gas, or compressed gas is essentially impossible for use in normal conditions. The losses of Hydrogen alone would kill the use. The natural solution is to store the Hydrogen as a Hydride. Much experimentation has been done with Hydrides. All solutions come back to the natural solution that Carbon Hydrides and essentially about 6 to 20 carbon Alcane chains (Gasoline Jet fuel etc) are just about the optimal solution.

      What is going to develop will probably be that Gasoline or similar fuel will be made using either Coal for the Carbon or by Hydration of poor quality vegitable oils or vegitable mass like Hydrilla or Algea. This will provide the store for the Hydrogen that may in fact be made from the same process fairly directly. This can be SOLAR in energy source.

      There are other features here that are most desirable. This provides a stable store which works with current technology. It is energy optimal. It is fairly clean and allows the addition of regenerative braking and other mechanisms.

      This is more or less what is going on. Sorry for those who thought that gasoline was going away, it looks as though it is here to stay for a long time to come. Fuel Reformers (Crackers for Hydrogen) will just make you have a 50 Kg Primary Energy Converter insted of a 500 Kg one. You will no longer have brakes or a transmission. Your controls will be as simple as computer joysticks. The

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    4. Re:Oil? by mwood · · Score: 5, Insightful

      Since there are no wells of molecular hydrogen anywhere on the planet, hydrogen will *always* be only a storage medium, *never* a direct energy source. Hydrogen production will be coupled with some other source of energy because that's the only way to get free hydrogen around here.

      But the extraction-from-hydrocarbon method has got to go. Notice the byproducts: carbon dioxide, carbon monoxide. Sound familiar? Aren't those a large part of the reason people have been whining about the need for alternative fuels?

      The nice thing about hydrogen is that you can make it from many different energy-producing processes and ship it fairly easily. (Try loading 40 tons of electricity on a truck.) We *should* be looking into efficient industrial-sized water electrolysis, or maybe some kind of thermolytic or photolytic process. 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. 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.

      Liberating hydrogen from oil is expedient in the short term, but it's stupid in the long term. Isn't short-term thinking how we messed up our atmosphere in the first place?

      That said, I'm happy to see an outfit with the size and clout of the U.S. Army getting serious about hydrogen. They can drive development to the point that the consumption end is a going concern, whether the production end is well thought out or not. Once there's a sizable demand for hydrogen fuel, there'll be money enough for bright people to tune up the supply side.

    5. Re:Oil? by Rostin · · Score: 5, Interesting

      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.

  2. This is a great first step! by Qwerpafw · · Score: 5, Informative

    The giant barrier for fuel cells is, and has been, transportation and distribution of fuel. Pure hydrogen is enormously expensive to transport and store since it "leaks" out of most containers (the molecules fit through the walls or something equally frustrating). Strides were made with that (boron?) chemical storage, but it's still pretty labor intensive and would require a vastly different infrastructure. This, however, manages to use the existing system (for diesel fuel) for hydrogen cells. That's a giant breakthrough.

    The article describes the technology as being "a four or a five" on a scale where 10 is production-level, so the whole thing is, to an extent, still vapourware. BUT, the transition path to hydrogren is so advantageous, I wouldn't be surprised if we were to see production examples of fuel-cell diesel trucks (apparently the tech works better with diesel...) in a few years domestically. First a transition for trucks, then a gradual increase in diesel/hydrogen fuel availability for the rest of America's car fleet, and finally a total switch to hydrogen tech. All without having to significantly rework the fossil fuel distribution network. This is the stuff of the future and I, for one, look forwards to it eagerly.

  3. Cost by sangfroid · · Score: 5, Informative

    They're using a catalytic converter to draw the hydrogen out of readily available, pre-processed fuel -- probably still in the form of hydrocarbons instead of pure hydrogen. This is cheap. Seperating salt water into Hydrogen, Oxygen, Salt, and extraneous junk is expensive.

    From the article:

    "Scientists have known about the advantages of hydrogen fuel since they began using it to power rockets. But super-cooled liquid hydrogen is difficult to store and move.

    Thus, converting to widespread use would be expensive and take years, and would require creating an alternative to the world's trillion-dollar infrastructure.

    But they realized there is already a lot of hydrogen in hydrocarbon fuel -- diesel fuel, jet fuel, gasoline. All they would have to do is invent a process that removes the carbon and sulfur and they could take advantage of the oil industry infrastructure."

  4. Costs by pubjames · · Score: 5, Insightful

    DoD officials say 'it costs about $40 to move one gallon of diesel fuel from Kuwait to Baghdad.'

    It really costs that much? Seems a hell of a lot to me. How many gallons does an oil tanker hold? Let's me guess at 20,000. If so, then to drive an oil tanker from Kuwait to Badhdad is costing $800,000!!

    I guess these must be the prices that Haliburton etc. are charging. The war in Iraq looks like a damn efficient means to move money from the American taxer into the hands of friends of those in power in the USA. Go Bush!

  5. They figured out hydrogens in hydrocarbons?? by Viol8 · · Score: 5, Funny

    "Auburn University scientists 'realized there is already a lot of hydrogen in hydrocarbon fuel'"

    Wow, theres no fooling with these guys. Those sharp megawatt intelligences are really on the ball, I mean its only been over a hundred years since
    most chemists realised the very same thing and even put "hydro" in the name of hydrocarbon as clue.

  6. Re: Tanks? by Catbeller · · Score: 5, Informative

    Actually, yes it did. The flame burned upwards, rather than out and down, napalm-like, as gasoline does. The heat was flaring away from the passenger compartment. Most of the people died from jumping from the airship when it was still too high from the ground. Those who kept their heads waited for the ship to drift to the ground, then hopped off and ran. They survived for the most part.

    And, oh yes, the bright searing flame you see in the picture? It's the paint. It was basically thermite. Powdered metal. The company wanted pretty silver shiny skin. One electrical arc, and WHOOMP - hydrogen gets the blame.

    And fuel cells fueled by gasoline or diesel are in no way more dangerous than a straight IC design! As a matter of fact, since you get more MPG, you can have a smaller tank of what is essentially napalm.

    Hydrogen is not "dangerous" in the sense that gasoline is. Gasoline is heavy, adhears to surfaces, ignites easily when vaporized, burns outward in a mushrooming effect, and also is every vehicle in America - and is dispensed from gas pumps like it is as safe as water!