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Microreactors Change Propane into Hydrogen 122

Posted by Zonk
from the gas-into-other-gases dept.
Roland Piquepaille writes "Microreactors have already been used for on-site reforming of fuels, such as methanol or propane, to produce hydrogen to be used in fuel cells. Now, researchers at the University of Illinois at Urbana-Champaign (UIUC) have designed very efficient ceramic microreactors to do this task. The scientists say that their microreactors are much better than other fuel reformer systems. They are now trying to reform gasoline and diesel, which are more widely distributed than propane. Does this mean that one day we'll be able to go to a gas station to refill the fuel cells powering our laptops? Probably not before a while, but read more for additional details, references and a picture of a prototype."
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Microreactors Change Propane into Hydrogen

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  • huh? (Score:5, Insightful)

    by Dan Guisinger (15506) on Saturday September 23, 2006 @09:31PM (#16171645) Homepage
    I don't get it..... ......aren't there better things we should be trying to turn into hyrdogen?
    I mean.... propane, oil, gasoline, thats great......but half the problem is we are running out. And what happens to all the carbon when its converted to hydrogen? (I admit I didn't read). I would hope its not released as an emission of sorts, that wouldn't help what so ever....other than localizing a problem possibly making containment easier.

    • Re: (Score:2, Insightful)

      by caseih (160668)
      The "Hyrdogen Economy" will never exist. It has not been and never will be an energy source. Energy storage maybe, but not a source. Even if you can take cleanly generated electricity and make hydrogen via electrolosis, I don't think it's viable, except in small applications like laptop fuel cells. Today almost all hydrogen comes from natural gas anyway. I guess these guys have just developed a more efficient way to get get the hydrogen extracted from it, but the byproducts are still the same (carbon di
      • Re: (Score:3, Insightful)

        by rolfwind (528248)
        Even petroleum is only "energy storage", it didn't get there by itself, but through millions of years, solar energy, and decaying plants/animals life cycle as far as we know.

        But agreed, current electrolysis is too costly, perhaps high temperature steam electrolysis too. Perhaps Fusion, when it comes, will solve these problems with sheer energy production, or high-efficiency solar panels or some other thing we can't currently imagine.

        But whatever the case, "never" predictions have a long time coming to be p
      • by rossdee (243626)
        "It has not been and never will be an energy source."

        on the contrary, Hydrogen has been the primary energy source for this planet for the last 4.5 billion years, and is likely to remain so for many years to come. The problem is that the reactor is 93 million miles away, so we only get a very small percentage of the generated energy.
        • we only get a very small percentage of the generated energy.

          Oh no, we get enormous quantities of it. Far more than we could easily use. I'd say the problem is that it rains down in the form of high-energy photons which are difficult to collect and store.
      • by localman (111171)
        You are absolutely right about the energy source / energy storage confusion. I've had a really hard time explaining that to even smart people. However, hydrogen doesn't need to be an energy source to be useful; a good energy storage & transportation medium would be a very useful thing over time. What I mean is that there is an advantage to abstracting our fuel sources; it allows us to switch out the underlying enegy gathering mechanism from the infrastructure. If we're on hydrogen already when fossi
        • All biodiesel needs is a better name. The current name evokes images of decaying vegetation and 'dirty' commercial vehicles. I propose we call it, "Energon," assuming Hasbro can be convinced to play along. It even already has the proper connotations as an energy transport system rather than an energy "source."
      • We have to be seriously careful when we start talking about bio-fuels. There is something intrinsically wrong with using our valuable food resources to satisfy our addiction for energy. Push wind, solar and fusion research. We have lots of room for exploration and improvement. Use these non-carbon alternatives to extract hydrogen from water. Fuel cells for cars are a good idea. Cars will not be able to accelerate as fast or reach the same top speeds, but traveling will be a reality.
    • Re:huh? (Score:5, Funny)

      by CoderDog (782544) on Saturday September 23, 2006 @10:15PM (#16171825)
      Suckered by a Roland Piquepaille submission, Again. Hate it when that happens.

      They mentioned that the reactor operates at high temps (800 C. to 1000 C.) to avoid carbon (as soot) fouling of the reactor. So, they've either got an ash bin somewhere downstream or they sprew CO and/or CO2. The other boast was that they'd reformed ammonia (at 1000 C.) to produce hydrogen. No word on whether the waste was gaseous nitrogen or nitrous oxides. Hope it's not nitrous oxides. Denver's "brown cloud" used to be mainly nitrous oxides from car exhaust.

      This looks like a really cool trick, but otherwise nearly worthless at this late date. I really don't want to run down to the gas station every couple of hours for a hydrogen recharge, and really, really dont't want a long warmup 800 C. appliance running in the house -- unless it also cooks 60 second pizzas. Additionally, the world's running out of their feedstock. If they had something that took plastic packaging, waste paper, saw dust, or the neighbors yapping little pets as an input and efficiently produced butane, propane, diesel or gasline, along with nicely segregated saleable piles of sulfur and laser printer toner, that'd be a newsworthy dazzling thing.

      If it also made nutritious little green biscuits (maybe call 'em Soylent Green?) that'd be extra special.
    • by rolfwind (528248)
      As I understand it, this is not so much aimed at being the transportation fuel technology of tomorrow, but supplanting the battery in applications where longer running times or higher energy output is needed.
      • by mark_osmd (812581)
        Another really good point about this kind of energy source is that a fuel powered system creates just as much power at the last second before it runs out of fuel as it did when it had a full tank. With a chemical battery you have real problems using that last bit of energy because the voltage and other factors of the battery change radically as the battery is drained. So you need complicated regulation circuitry to even do it well.
    • I agree that this is a complete waste of time. Aside from the fact that they are trying to extract hydrogen from a scarce commodity, what purpose will this hydrogen serve? I can see an application for lab use or research or maybe a theoretical fusion reaction, but it's a very inefficient application for fuel cells or any other environmentally-conscious endeavor. Maybe i'm just frothing from the mouth a bit after just seeing "who killed the electric car".
    • Re:huh? (Score:4, Interesting)

      by Jah-Wren Ryel (80510) on Saturday September 23, 2006 @11:01PM (#16172021)
      aren't there better things we should be trying to turn into hyrdogen?

      Right now, today, we only have one, maybe two, wide-scale energy distribution systems. Its gasoline. If we can easily and cheaply make a gas station do double-duty as a hydrogran station that solves the short term problem of how to fill-up hydrogren powered cars. The expectation is that over time, as hydrogren powered cards theoretically become widespread, we can slowly build up alternate distribution system(s) to support them as we wean off of gasoline.

      PS - the other "maybe" distribution system is electricity. I say "maybe" because we do a power grid, but we don't have metered charging stations nor do we have the capacity to support wide-scale automobile recharging. Yet. Start putting some nukes online and we might get there pretty quick.
      • by Nutria (679911)
        PS - the other "maybe" distribution system is electricity. I say "maybe" because we do a power grid, but we don't have metered charging stations nor do we have the capacity to support wide-scale automobile recharging. Yet. Start putting some nukes online and we might get there pretty quick

        It would definitely have to be nuke, or some form of efficient alternative source, because burning more coal is just a non-starter.

        A big problem, though, is transmission. 5,000,000 electric cars would add a huge load to t
        • by strstrep (879828)
          Adding electric cars won't happen purely overnight. It will happen gradually, and the grid will expand to handle the demand.
          • by Nutria (679911)
            It will happen gradually, and the grid will expand to handle the demand.

            Power companies are very reluctant to restring thousands of miles of wire. They'd rather live with the status quo.

            • by strstrep (879828)
              If there's more profit to be made by delivering more electricity, they will sure run more wires ... or their competitors will.
        • by Muad'Dave (255648)
          Most of the electric cars would recharge overnight when the existing grid is under-utilized, so it wouldn't be such a massive impact.
          • by Nutria (679911)
            Most of the electric cars would recharge overnight when the existing grid is under-utilized, so it wouldn't be such a massive impact.

            Good point.

            On a slightly different, but definitely related topic: ISTR that the utilities use the evenings to take some generators off line and do preventative maintenance and repair work. If so, they would not be able to do as much such needed work.

      • by mpe (36238)
        Right now, today, we only have one, maybe two, wide-scale energy distribution systems. Its gasoline. If we can easily and cheaply make a gas station do double-duty as a hydrogran station that solves the short term problem of how to fill-up hydrogren powered cars. The expectation is that over time, as hydrogren powered cards theoretically become widespread, we can slowly build up alternate distribution system(s) to support them as we wean off of gasoline.

        Probably more economically viable to come up with a
    • What you turn into hydrogen is really not the issue.

      Where you get the energy is. As long as we are still using fossil fuels, it is better to be able to put them into a fuel cell and get almost all the energy out in the form of electricity, instead of burning it in turbines and internal combustion engines where we only use around 25% of the energy converted. (the rest is mostly waste heat)
    • by coolcold (805170)
      I believe they are finding cheap ways to produce hydrogen first and get the population to start using hydrogen. Producing hydrogen using different resource would probabily be the next step. Besides, if they dont use up all the propane, oil etc first, how could hydrogen be cheaper?? XD
    • by tacocat (527354)

      This is a rather stupid concept. Take a readily available, limited, and consumable product and turn it into another consumable prodect that has limited distribution and use. The whole point in pushing this hydrogen fuel cell economy isn't so that we can continue to invade middle easter oil rich countries for sources of hydrogen instead of oil, but that we don't have such a dependency upon them.

      Think how the entire Middle East history of the last 100 years would be if there was no oil there? No one would

    • "but half the problem is we are running out."

      No, that's not half the problem at all. Or even close to it. The bulk of the problem is the lack of a better alternative. Ethanol is great in concept, but cannot be very efficiently produced in the US (it takes almost as much energy to produce it as you get out of it, etc). Solar and Wind power are very clean and cheap, but generally don't produce enough energy to power most devices (does your car look like this [www.web.ca]?).

      When you say we are running out of oil, y
    • by freqres (638820)
      This does break open the chicken-egg problem with hydrogen vehicles and a distribution system for hydrogen. If all of the currently operating gas stations can easily offer hydrogen with some kind of on-site converstion unit it creates a much better position to get people to buy hydrogen or multi-fuel vehicles. Once people have hydrogen powered vehicles on the road you just change the way hydrogen gets to the fuel stations. Right now the investment in a whole new hydrogen distribution system is probably o
    • by salec (791463)

      And what happens to all the carbon when its converted to hydrogen?

      According to the paper they published, you get CO (carbon monoxide), which is yet another fuel and (hopefully, as it is toxic) probably subsequently oxidised into CO2. This oxidation will release some extra heat, as well. It would be nice if that heat is reused in process (which involves heating steam to 1000 degrees Celsius). Anyway, IMHO, it is too dangerous tech for placing it near to end users(' private parts), in laptops, etc.

      This turnin

    • by cbacba (944071)
      Despite the best efforts of some ludites, we are not about out of fossil fuels. As usual, we are close to the limit of diminishing returns for exploring for more. It makes little sense at the top level to spend too much money hunting just to extend the amount of known reserves that won't be developed for 50 years. It is possible we are at or are nearing a time where we are out of cheap energy, at least for the moment.

      One must understand the difference between a means of storage of energy and a source of
  • by dbIII (701233) on Saturday September 23, 2006 @09:41PM (#16171673)
    One thing I would like to hear is if you really get much better results with this and hydrogen-oxygen fuel cells than you would get with a propane-oxgen fuel cell. If it is a much larger difference than you get with reforming the propane then it is interesting - propane is easier to store and ship around.
    • > One thing I would like to hear is if you really get much better results with
      > this and hydrogen-oxygen fuel cells than you would get with a propane-oxgen
      > fuel cell.

      Where do I get a propane-oxygen fuel cell?
      • by crmartin (98227)
        Don't know where you'd buy one, but they certainly can be (and have been) made. My family sold propane and propane equiment when I was a kid (yes, they had fire then) and we had, as an advertising gimmick, a gas TV to go with our gas refrigerators and gas dryers. Propane fuel cell gave us 12 v DC for a small black and white TV.

        (Yes, we had fire, but it was black-and-white fire --- I don't remember color TV until I was rather older.)
        • > Don't know where you'd buy one, but they certainly can be (and have been)
          > made.

          There are devices that are marketed as propane fuel cells, but they are actually hydrogen fuel cells with reformer front-ends to produce hydrogen from propane.

          > Propane fuel cell gave us 12 v DC for a small black and white TV.

          Are you sure it was a fuel cell?

          > Yes, we had fire, but it was black-and-white fire --- I don't remember
          > color TV until I was rather older.

          Young, aren't you?
        • Re: (Score:3, Funny)

          by sydsavage (453743)
          My family sold propane and propane equiment when I was a kid

          Bobby Hill, is that you?

      • by njh (24312)
        Here: http://www.powergeneration.siemens.com/en/fuelcell s [siemens.com] They are actually hydrocarbon-air fuel cells (or indeed a range of other suitable reductants). And they exist (I've held one in my hand).
  • by KalElOfJorEl (998741) on Saturday September 23, 2006 @09:43PM (#16171685)
    Turning hydrogen into fossil fuels. Now THAT would be something to see.
    • Synthesizing hydrocarbons is quite straightforward. It just requires a lot of energy (and a supply of carbon and hydrogen, of course).
    • How about turning Carbon Dioxide into hydrcarbons via solarvoltaics?

      This link goes there. [europa.eu]

      This link goes projects home. [europa.eu]

      It also uses nanotubes, and we all know how cool they are. :)

    • Re: (Score:2, Funny)

      by kfg (145172) *
      Turning hydrogen into fossil fuels. Now THAT would be something to see.

      They're called "plants" and "fungi." Perhaps you've heard of them? The hydrocarbon compound they produce is often refered to colloquially as "vodka."

      KFG
      • by modecx (130548)
        Hey, that's just what we need to do. We need to engineer plants to secrete ethanol directly, so we can skip providing food for trillions of fungi. We can siphon it off just like maple syrup!

        Muahaha!

        Of course the damn government will have to come in and spoil our fun by requiring our vodka trees to output denatured vodka syrup.

        Bastards.
        • by kfg (145172) *
          Of course the damn government will have to come in and spoil our fun by requiring our vodka trees to output denatured vodka syrup.

          I fooled them, Grandma, I switched to biodiesel. For purely asthetic reasons I prefer my long hydrocarbon chains capped by an oxygen finial. The particular formulation of biodiesel I'm partial to is refered to colloquially as "Gouda." In order to assemble the long chains from the plant matter you will require a processing device known colloquially as a "cow."

          KFG
    • Fossil fuels in the last century reached their extreme prices because of their inherent utility: they pack a great deal of potential energy into an extremely efficient package. If we can but sidestep the 100 million year production process, we can corner this market once again.
  • vaporware (Score:5, Funny)

    by macadamia_harold (947445) on Saturday September 23, 2006 @10:09PM (#16171805) Homepage
    Microreactors Change Propane into Hydrogen

    Finally, a good example of vaporware. And not in the Duke Nukem Forever sense of the word.
  • Whatevs (Score:5, Funny)

    by Y-Crate (540566) on Saturday September 23, 2006 @10:20PM (#16171849)
    This shit is nothing. I'm putting the finishing touches on a process that will turn diamonds into multifunction printer paper.
  • Hank Hill can get into the Zepplin buisness now.
  • From the article:

    In their latest work, the researchers incorporated the catalyst structure within a ceramic housing, which enabled the steam reforming of propane at operating temperatures up to 1,000 degrees Celsius. Using the new ceramic housing, the researchers also demonstrated the successful decomposition of ammonia at temperatures up to 1,000 degrees Celsius. High-temperature operation is essential for peak performance in microreactors, said Kenis, who also is a researcher at the university's Beckman

    • He said that we're not gonna see it in laptops for a while for a reason, man.
    • by ScottBob (244972)
      Well, maybe if it was inside a tiny thermos bottle, it wouldn't be so bad... Heck, if it was made to the same size and form factor as a vacuum tube, it would be more readily acceptable, since vacuum tubes have been with us for a long time. Think about it- The filament in a vacuum tube gets way, way hotter and nobody complains about that, because it's insulated by the vacuum inside. Besides that, people can show off the glowing innards of their micro-reactors the way they do with high end tube powered stereo
      • by ddillman (267710)

        Heck, if it was made to the same size and form factor as a vacuum tube, it would be more readily acceptable, since vacuum tubes have been with us for a long time. Think about it- The filament in a vacuum tube gets way, way hotter and nobody complains about that, because it's insulated by the vacuum inside.

        Have you ever seen/felt vaccuum tubes in operation? You can very easily burn yourself on them. I remember old tube type televisions, and the red glow inside from the hot tubes. I've heard of people b

  • and/or landfill methane. OTOH, a process that turns those into CO2 probably isn't the best, unless we have a way to convert that waste stream into something more useful. I've seen, and worked on some chemistry, for that, but not really on the scale they'd need here. I suppose we could use a varient of carbonic anhydrase to convert the carbon dioxide to carbonate anions, which could be co-precipitated with calcium to form the Great DuPont Reef of Northern Delaware, but that's a different project.

    [OffTo
    • I think the point is to be able to generate electricity much more efficiently. This is not a replacement for a gasoline engine in your car. It's a replacement for a laptop battery for a traveling salesman or satellite-phone battery for a USMC lieutenant in the field.

      As such, it's a big win. Batteries are an environmental disaster, since they often need nasty heavy metals (e.g. lead or mercury), and they don't last very long. Furthermore, you waste a lot of transportation energy transporting around the m
    • This isn't the only research on the subject at the moment. From The Chemical Engineer magazine:

      HUI Tong Chua, professor of mechanical engineering at the University of Western Australia (UWA), believes he has cracked the problem of how to break up methane into its constituent components of hydrogen and carbon without creating carbon dioxide - which, while much less potent than methane, is still an important greenhouse gas.

      The process, which is currently under consideration for the UWA "Inventor of the Year"
  • Benefits. (Score:2, Insightful)

    by Jartan (219704)
    I think the point of turning gasoline into hydrogen would be that it would finally solve one of the biggest problems with fuel cell acceptance. The problem of where do you "fill up".

    If your car has a method of efficently turning gasoline into hydrogen then a huge distrubition problem is solved. Fuel cell cars could become accepted much more easily because you wouldn't have to worry about being out of fuel. Yet in a large majority of the cases you'd never actually need to fill up at the gas station assum
    • Re: (Score:2, Funny)

      by kfg (145172) *
      Yet in a large majority of the cases you'd never actually need to fill up at the gas station assuming you recharged your fuel cells overnight.

      Fuel cells are "recharged" with. . .hydrogen, not electricity. The electricity is stored in. . .the hydrogen. When the hyrdrogen is gone, so is the electricity. That's the way it works.

      If you want to recharge your electric car overnight without going to a filling station you'll need a battery. Perhaps you can use it to make it back to the filling station.

      http://www.ho [howstuffworks.com]
  • Yet again... (Score:2, Insightful)

    Making a fossil fuel "alternative" with fossil fuels.

    Hydrogen and fuel cell technology as it stands today is a white elephant of epic proportions. When you convert one form of energy to another, there is always a loss of efficiency. Instead of just converting the fossil fuel to energy in the vehicle, it's converted into another form of fuel, losing efficiency.
     
    You actually use MORE petroleum running a hydrogen car than an equivalent gasoline-powered vehicle.
    • ...converted into another form of fuel, losing efficiency.
      Very true. However, that doesn't neccessarily mean that the end result is less efficiency. There are other factors, such as how efficient the process of extracting power from hydrogen is (the answer to which is very, compared to good-old gasoline combustion). Efficiency = total input/usable output
      • Yay, I fucked up the blockquote tag.
      • Hmmm. I didn't think about that. The problem is though, we're still using fossil fuels. The whole point of using alternative fuels like hydrogen is to be free of them.
        • by rts008 (812749)
          Yeah, I'm thinking the same.
          Kind of like being stranded in the desert and making Koolaide to drink to conserve water.
  • by loshwomp (468955) on Sunday September 24, 2006 @12:40AM (#16172427)

    Here's a paper from AC Propulsion that explains why fuel cells are the technology that never will be. The smart money got out of fuel cells years ago.

    Perspectives on Fuel Cell and Battery Electric Vehicles [acpropulsion.com]

    • by donaldm (919619)
      Mod this up.

      The pdf "Perspectives on Fuel Cell and Battery Electric Vehicles" is quite an informative read although it was written on 2002, but a lot of what is said is still relevant today.

      I think the summary says it all:

      Battery electric vehicles based on the same platform as fuel cell vehicles can have
      greater range than the fuel cell version if latest battery technology is employed.

      Making hydrogen with electricity is very inefficient. Compared with battery electric
      vehicles, electricity con
      • Re: (Score:2, Informative)

        by Anonymous Coward
        Nice article, untill it told me that 1 KG of Hydrogen weighed the same as 1 gallon of gas. 1 gallon of gas weighs 6.5 lbs, or 2.9 kg and at 45 or so miles per Kg, you could get approx. 130 miles by carrying the same weight as the equivilant amount of gas. It's just a personal bais of mine, but when i see an article lie to me i stop listening to it.
        • It doesn't say this at all. It says that 1Kg of hydrogen has a similar chemical energy to a gallon of gasoline.

          Given the relative atomic mass of carbon and hydrogen, and that gasoline is a hydrocarbon fuel, I can, without reference to a chemistry textbook, immediately reckon in my head that this is not a wild or outlandish claim.

          Perhaps you should read more carefully, before dismissing an established, repected commentary out of hand?

          Of course, given that you need heavy, specialized storage equipment to carr
        • by tgd (2822)
          Maybe if you were reading instead of listening, you wouldn't have totally misinterpreted what they were saying.

          Go back and read it again.
  • Propane is a nice alkane between ethane and butane whose properties are very useful in certain applications. Nothing is accomplished by converting it to hydrogen. Go pick on water or methane!
    • From what I am looking at, ceramic micro reactors sound a whole lot like what a Catalyst could do. Now if the folks that made this reactor could go stare at Lake Michigan and ask themselves, "How can I get Hydrogen from this lake?" Now we got a news article worth perking our ears up about. I am hoping that some pre grad student at U.I.C. does not get the memo that says you can not get hydrogen from oceans, and large lakes; And this student starts looking at some kind of algae that outputs hydrogen, and o
  • by bradbury (33372) <Robert...Bradbury@@@gmail...com> on Sunday September 24, 2006 @05:08AM (#16173331) Homepage
    People in developed countries have largely been duped by the so called "green" arguments that hydrogen (and indirectly fuel cells) are the solution to their energy problems. This is because you combine hydrogen with oxygen and get nonpolluting water (thus no CO2 and no CO). If done in a fuel cell the secondary reactions with N2 are avoided and thus no NO. This means no pollution. But existing automobiles through the proper management of the air fuel mixture (computer controlled fuel injection) and catalytic converters have minimized the NO problem.

    You have to separate the problem of the energy carrier from the energy source. All current existing methods to make hydrogen available start with upstream in-the-ground based energy sources (methane, propane, gasoline, etc.) and involve dumping the CO2 that results from extracting the hydrogen into the atmosphere. So long as the hydrocarbon (or carbon) source is coming out of the ground you have only solved the NO pollution problem -- you haven't solved the CO2 part of the global warming problem. I.e. you have not produced a sustainable solution.

    The only sustainable solutions involve producing hydrocarbon carriers using carbon extracted from the atmosphere -- that currently means biodiesel, bioethanol or biomethane. Propane, methane and gasoline in our current economy are energy carriers produced using solar energy harvested in ancient times. Until one switches to an economy based on energy harvested or created in real time one has an unsustainable reality. That means one has to be harvesting solar energy (incident visible or IR energy, wind or hydroelectric) or nuclear energy (in the long term using breeder reactors or fusion). The bio-carrier sources are inefficient (harvesting 1-2% of incident solar energy) but there is a large installed infrastructure designed to produce them. As whole genome engineering and/or mass production of inexpensive photovoltaic cells increase the solar energy harvesting efficiencies it will become completely feasible to migrate from a "steal from the past" to a "harvest the present" sustainable economic framework. It would help if people could keep this straight in their minds (and if people in leadership and press positions would not mislead or misdirect where the emphasis should be placed).

    So I agree with comments that better reformers are not particularly worthy of attention. A more efficient catalytic system for splitting water (compared with photosynthetic efficiencies) would be worth getting excited about.

    Of course I'm waiting for the day when our fusion reactors are powering the breeding of Gd-148 which in turn is used to power the nanorobots and/or replicators which will sustain our economy. But we are probably a several decades away from that at this time.

    • Re: (Score:3, Interesting)

      by evilviper (135110)

      All current existing methods to make hydrogen available start with upstream in-the-ground based energy sources (methane, propane, gasoline, etc.) and involve dumping the CO2 that results from extracting the hydrogen into the atmosphere.

      I think the issues that should be discussed is how terribly ineffecient such conversions are, plus the ineffeciencies in the fuel cells, etc. It would be far more effecient to burn the propane/gasoline in a power plant, and charge a battery-powered car from the grid, and bat

      • by bradbury (33372)
        Given the basic thermodynamics (higher temperatures ~= high efficiency) oxidizing the energy carrier in a power plant (rather than individual vehicles) is likely to result in higher efficiency. So assuming the electricity transport losses are not too high it is going to be better to use batteries (or high capacity capacitors!) rather than fuel cells. The most efficient approach however would involve direct production and storing of the electrons using solar power as the energy source. I could imagine a s
    • Summary: "Blah blah blah, I'm more pretentious than you."
      • by bradbury (33372)
        That may be true (though the word others sometimes use is arrogant). The point would be not whether I am best described by either of those terms but whether my post was informative and enabled people reading it to more clearly think about the relative importance of various aspects of the problem.
  • Does the conversion to useful energy without any intermediate step of a fuel cell too.
    It's otherwise known as the petrol engine in my car. LPG [wikipedia.org]

    I didn't see any mention of efficiency in TFA, apart from it being "very efficient". I do however recall something about how much more efficient an internal combustion engine would be if made from ceramic, and allowed to run at much higher temperatures.
  • Bad news, folks. This is a standard PR release to hype up the chemists results. Thr problem with this work is simply that it has to be carried out at 500 to 1000 degrees. Do you really want to power your PDA with that? And besides: the conversion of propane etc to H2 and C is endothermic at 25 deg. This accounts for the 1000 deg microreactor.
  • Take some propane, subject it to a process that runs at 1000d C, and convert it to hydrogen and presumably carbon-something-or-other. So, how to get the 1000d temperature? Maybe burn some kind of fuel? Maybe burn some PROPANE? How much energy does it take to extract the hydrogen from propane anyway? Or to put it another way, how much equivalent propane is used up to generate the energy necessary to make a given amount of hydrogen?

    Why not just burn the propane directly in an automobile engine or otherwise

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