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Power Transportation Science Technology

Hydrogen-Powered cars with Zero-Carbon-Emission? 203

Roland Piquepaille writes "Researchers from the Georgia Institute of Technology have a bright idea — at least at first sight. They want to create a sustainable transportation system by using hydrogen-powered cars. They would like to create an infrastructure where people could use a liquid fuel for driving while the carbon emission in their vehicles is trapped for later processing at a fueling station. 'The carbon would then be shuttled back to a processing plant where it could be transformed into liquid fuel.' Where will all this liquid carbon be stored? The researchers don't know. They suggest that it could be stored in geological formations or under the oceans."
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Hydrogen-Powered cars with Zero-Carbon-Emission?

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  • by KublaiKhan ( 522918 ) on Thursday February 14, 2008 @05:15PM (#22426914) Homepage Journal
    The carbon-fibre industry's been taking off like a rocket, and we keep studying those nanotubes. The manufacturers are going to need carbon to make 'em. Why waste time and money burying it under the ocean or in the middle of a mountain?

    Waste not, want not.
    • With all that surplus carbon you should be able to give your Valentine a diamond the size of a brick.

      Folks, we have no shortage of C, that's why there's a disposal problem.

      Hint to moderators: parent was hoping for funnies, not insightfuls.

    • by Zymergy ( 803632 ) * on Thursday February 14, 2008 @06:05PM (#22427592)
      Combustion Carbon will be in the form of Carbon Monoxide (CO) and/or Carbon Dioxide (CO2). We do not have technology to create solid forms of carbon (quickly enough) to be useful on a passenger vehicle. (but that would be cool)
      Both of these waste carbon gases (CO2 and CO) require significant refrigeration with high compression to store them in any significant quantity and that, my friends, *Requires tremendous Energy*. The work of "sequestering" the Carbon and storing it will eat away any profits in the manufacturing of and efficiency of the vehicle and it will add complexity to an already complex piece of machinery. Not to mention there will have to be one or more pressurized vessels (think explosion, frostbite, and suffocation hazards potentials too).
      Carbon Sequestering is a pipe dream (thermodynamically) but it is great for getting venture capital from those investors who have not studied and understood the principles of thermodynamics and basic organic chemistry and who also want to claim that they are investing in "green" technology. (And there may just be tax breaks for such obvious non-competitive investments like 'Sequestering' to the 'Fossil Fuels Industries'??)
      "Carbon Sequestering" is really only handy (though still very efficient) if you happen to be talking about a sessile terrestrial power installation over a suitable subterranean geological Carbon gas receiving reservoir. Like this one: http://science.slashdot.org/article.pl?sid=08/02/03/1845204&from=rss [slashdot.org] (A budget increase from 1.0 Billion to 1.8 Billion proves its inefficiency alone, and that's before you consider how much more fuel is required to capture all of the HOT exhaust and cool it down to the point it could be compressed and injected into exhausted/abandoned Oil or gas 'injection' wells.

      The "Oceans" basically make CaCO3 (Calcium Carbonate) out of CO2 and CO (with the help of Trillions of organisms) and it falls to the ocean floor and becomes rock eventually. This is the PRIMARY carbon "sink" on the planet. I would put more research into helping that process (oceanic Carbon capturing) and focus on Electric Cars powered by Hydrogen cells and NOT Hydrocarbons and not Hydrogen combustion engines... they are too inefficient. Carbon is simply not needed in the fuel cycle. (Unless you want fuel cells that run off of Natural Gas (Methane/Ethane AKA CH4/C2H5) or some form of Alcohol (Methanol/Ethanol AKA CH3OH/C2H5OH)).
      Ultimately, using electricity to power the car's electric motor is the only truly efficient way to go (as of today)... It is only a matter of whether it is powered from a battery that is charged with electricity from the grid (preferably Nuclear and/or Hydroelectric), from an internal generator burning fuel (like modern diesel/electric Trains), and/or capacitors, solar cells, or small nuclear reactors... Burning Carbon-containing fuels (from whatever source...but note: they *WILL be from Fossil Fuels* as long as they are cheaper) is just more of the same since the invention of the combustion heat engine. It is business as usual.. Using Corn to make alcohol is a pretend market that will utterly fail without the heavy government subsidies it is seeing. (Research ADM and its lobbying efforts.)

      Carbon Sequestering is really interesting, but it requires TOO MUCH energy to do.. Last time I checked, you use about 2 Watts of power to remove about 1 Watt of heat from your home/office using efficient air conditioning. What will it require in energy to remove the heat and to compress (compression releases MORE heat BYW) the exhaust of a car buring some Carbon-containing fuel? Exactly. Electric is the ONLY way to!
      • by Rei ( 128717 ) on Thursday February 14, 2008 @07:04PM (#22428334) Homepage
        and focus on Electric Cars powered by Hydrogen cells and NOT Hydrocarbons and not Hydrogen combustion engines... they are too inefficient.

        You talk about efficiency and advocate hydrogen fuel cells in the same sentence? You do realize that hydrogen fuel cell vehicles are extremely inefficient, right? At low loads, fuel cell vehicles are typically 46% efficient at turning hydrogen in the tank into wheel torque and 36% in the NEDC driving cycle [doi.org]. On top of that, you have generation losses (modern power plants are 40-50%, older ~30%, and possibly up to 60% in the future), transmission losses (7.2% average in the US), electrolysis losses (80-85% efficiency if done in the most efficient manner possible, regeneratively on hot steam). Which makes hydrogen worse than gasoline in terms of a carbon footprint. You can also make it from methane reforming, but that's no better. You can grow it from bacteria, but that costs an utter fortune. There are direct sunlight to hydrogen cells, but they are expensive, very inefficient, and break down quickly.

        The hydrogen economy [daughtersoftiresias.org] is simply unrealistic. On the other hand, there is an awful lot of promise in electric vehicles [daughtersoftiresias.org].

        • by Zymergy ( 803632 ) * on Thursday February 14, 2008 @07:25PM (#22428594)
          You make a very good point, Thank You. I do not disagree, I should have re-read the post before submitting
          Hydrogen Fuel Cells are not as efficient as what I would consider to be "Efficient" either. BUT, they are more efficient than the burning any Carbon-containing fuel in order to spin a generator or to spin a drive shaft. I was thinking of Hydrogen fuel cells as being more efficient than the mechanical "heat engines", but you are absolutely right. (plus fuel cells have to have ultra-purified fuel stock and the membranes breakdown and become even less efficient, etc...

          I am hopeful that the new Lithium-Silicon-Nanowire Batteries as discussed here recently will make the rechargeable storage-battery to electric motor-powered passenger vehicles efficient and practical: http://hardware.slashdot.org/article.pl?sid=08/01/16/027236 [slashdot.org]
          A Toyota Prius with one of these new batteries (about the same size/weight as the existing Toyota Lithium Ion battery module) would have a range of over 300 miles per recharge (about the range of a standard fuel tank's worth of gasoline and farther still if one pulled out the gas engine and added more battery capacity under the hood too).
          • by Rei ( 128717 ) on Thursday February 14, 2008 @07:30PM (#22428672) Homepage
            Do realize that those batteries don't provide a 10x increase in energy density. After the first charge, the capacity drops to only 8x. Furthermore, it's only an anode advancement, so it would only provide a 2-3x increase in battery density. Of course, in pure electric vehicles, that's good enough to put them on range-parity with gasoline. Other techs that have the potential to do the same are lithium vanadium oxide and barium titaniate ultracapacitors.

            Also, two neat things happen as you increase the energy density. Unless they cost a lot more to manufacture, you lower the cost per stored watt at the same time. Also, you reduce the number of charge/discharge cycles they need to be able to tolerate, since a single charge/discharge cycle takes you further. Then factor in mass production on top of that all...

            Yeah, the future for EVs looks pretty good right now.
            • by mlts ( 1038732 ) * on Thursday February 14, 2008 @11:05PM (#22430460)
              Another thing that the hydrogen/fuel cell "economy" is missing is the fact that there are virtually zero hydrogen fueling stops. The cost to put in hundreds of thousands of H2 pumps and the infrastructure to haul the liquid H2 to the corner gas station will be enormous.

              Electric cars? Got a 120VAC or a 240VAC outlet? Its not that simple because 120VAC won't charge a car's batteries quickly (though its viable for overnight use.) However, adding circuits and having people standardize on a charging mechanism for cars when parked in parking lots is a lot simpler than the tanks, transportation, and specialized fuel dispensing systems needed for hydrogen. The technology for bringing electricity to every car in a parking lot does exist -- Many Alaskan shops and businesses have plugs for customers to plug in their engine heaters because at -20 (F) and below, the oil starts solidifying in the car.

              I look forward to electric cars. In a lot of cities, 100% of power comes from wind and solar, so its not shifting the carbon to another source. Slow charging can be done at home, fast charging (especially with supercap batteries that can charge very quickly) can be done at the normal filling stations, so the existing gas stations won't be losing market anytime soon.

              I don't look forward to a hydrogen economy, and the bugs and hassles a vastly new fuel infrastructure will bring with it. Not to mention the fact that someone has to pay the cost of sinking the H2 tanks underground in tens of thousands of gasoline stations... and that will end up being the customer.
        • by khallow ( 566160 )
          Eh, while electric engines are somewhat more efficient than internal combustion or hydrogen fuel cell, they aren't that impressive. They have the same power generation inefficiency and higher transmission losses than hydrogen. Then toss in the considerably lower energy density of electricity storage and even though you might get more wheel torque from the original source, the vehicle is going to be heavier than a fuel cell driven vehicle (even though the latter will probably have some sort of electricity st
          • by Rei ( 128717 ) on Friday February 15, 2008 @01:40AM (#22431218) Homepage
            Eh, while electric engines are somewhat more efficient than internal combustion or hydrogen fuel cell

            Huh? What planet are you from?

            * ICE: 30-35% efficiency for the engine, but due to internal losses, only about 20% efficient to the wheel well
            * Fuel cell: 40-60% efficient *before* the power goes to the electric motor.
            * Electric motor: 85-90% efficient in typical driving conditions (in optimal conditions, with an optimal engine, you can near 95% efficiency).

            They have the same power generation inefficiency and higher transmission losses than hydrogen.

            Huh? In the US, there's only an average 7.2% efficiency loss in electricity transmission. That doesn't even compare to the energy costs of making and pressurizing/pumping hydrogen.

            [quote]Then toss in the considerably lower energy density of electricity storage[/quote]

            Once again, huh? Hydrogen not in a storage medium will get you 250 miles, perhaps 300 at best. Li-ion present-day typically gets 200-250, but there are three different techs being worked on which each individually can 2x-3x that range (lithium vanadium oxide, silicon nanowires, and barium titanate caps). To get the range on hydrogen up, you need to either increase the pressure (which nobody wants to do), use liquid hydrogen (whole host of major, major problems that nobody wants to deal with), or use a storage medium. With a storage medium, you can get up to 300-350x (the reported range of the upcoming all-electric ZAP-X is 350mi, might I add -- and 300-350x is still way below the upcoming battery techs), but you lose even more efficiency in the process. The more hydrogen dense a storage medium, in general, the more inefficient it becomes. So, you take something that's already less efficient than an ICE, and you're making it *even worse*.

            and even though you might get more wheel torque from the original source, the vehicle is going to be heavier than a fuel cell driven vehicle (even though the latter will probably have some sort of electricity storage as well).

            Since when are fuel cell vehicles any lighter than electrics? The FCX weighs in at almost two tons. The Tesla Roadster's not even 1 1/2 tons.
            • Re: (Score:3, Informative)

              by khallow ( 566160 )

              Let's try this again. First, in the vehicle, electric motors are maybe twice as efficient as a fuel cell. Second, as mentioned early, making hydrogen from electolysis is around 85% efficient with minor losses from pressurizing and pumping hydrogen. That's because most of the energy of pressurization can be recycled by the time it gets used in the vehicle. I figure 90-95% is reasonable depending on how much of the energy of pressurization can be recovered (if it's in the car, it's ptobably going to be far lo

      • Re: (Score:3, Interesting)

        Comment removed based on user account deletion
    • Wow, all that carbon will make a lot of nano tubes. Think of how fast the internet will get! Of course, you can only send really small web pages...
  • Hydrogen? Carbon? (Score:5, Insightful)

    by _merlin ( 160982 ) on Thursday February 14, 2008 @05:18PM (#22426946) Homepage Journal
    First you say the cars are hydrogen-powered, then you say the carbon emissions will be trapped and disposed of when refuelling. Hydrogen doesn't contain carbon. Where do carbon emissions come from? This has to be the most contradictory Slashdot summary in a long time.
    • Re:Hydrogen? Carbon? (Score:5, Informative)

      by moderatorrater ( 1095745 ) on Thursday February 14, 2008 @05:21PM (#22426988)
      That's one of the worse summaries I've seen on Slashdot, and as we all know, that's saying something. Basically, there are three parts to the plan. Instead of using an internal combustion engine, you use a reactor that changes the hydrocarbon chains into hydrogen and carbon. The hydrogen is used to power the car using the already developed fuel cells while the carbon is stored. You fuel at a station, but instead of just filling up with hydrocarbon (like we do now), you also give back the carbon that your car's been storing.

      In the short term, this carbon would be taken and sequestered in a variety of methods that scientists have been studying for years, either under the ocean, in old oil wells, other underground locations, or in solid carbonate form. In the long term, the carbon would go back and be remade into hydrocarbon chains to be distributed back out. As someone else pointed out, you could also use the carbon for nanotubes.
      • by Kuukai ( 865890 )

        In the short term, this carbon would be taken and sequestered in a variety of methods that scientists have been studying for years, either under the ocean, in old oil wells, other underground locations, or in solid carbonate form.
        And this can in turn be used by the Hutts to freeze smugglers who owe them money. Yesss, it's all coming together perfectly...
        • Re: (Score:2, Funny)

          "And this can in turn be used by the Hutts to freeze smugglers who owe them money."

          Until some do-gooder bitch comes along and unfreezes them, thus fucking up the climate for us once again!
        • or in solid carbonate form


          Hate to break it to you but that was carbonite not carbonate.
          Carbonate is the CO3 ion that makes limestone (CaCO3) and dolomite (CaMg(CO3)2)

          It would have been interesting if Han was turned to limestone but a marble statue of Han would have been a little too Clash of the Titans.
      • by RingDev ( 879105 ) on Thursday February 14, 2008 @05:36PM (#22427216) Homepage Journal
        Step 1: Generate pure hydrogen in highly efficient processing plant
        Step 2: Merge with carbon to create less stable and lower density hydrocarbon based fuel
        Step 3: Using a vehicle based unit, crack the hydrocarbons back into hydrogen and carbon
        Step 4: oxidize hydrogen to power fuel cell.
        Step 5: return carbon to processing plant.

        This would work amazingly if there were a shortage of carbon and an excess of easily accessible hydrogen. Unfortunately, our problem is the other way around. I can walk to any local gas station in the middle of summer and pick up a 20lbs bag of carbon for a few bucks. Getting my hands on 20lbs of hydrogen is a bit more challenging and expensive.

        Not to mention there is no way they are going to get a vehicle based cracking unit to be more efficient than the factory unit. Not to mention that energy density is already an issue in pure hydrogen storage, turning it into hydro carbons isn't going to help on that issue if they are only using the hydrogen for energy generation.

        The whole concept seems to fall on it's face as yet another attempt at a perpetual motion device.

        -Rick
        • Re:Hydrogen? Carbon? (Score:5, Informative)

          by Rostin ( 691447 ) on Thursday February 14, 2008 @06:36PM (#22427976)
          You were doing more or less ok until you got to the energy density part.

          According to Wikipedia, liquid hydrogen has a density of 70.8 kg/m^3. That sets a generous upper bound on the density we could hope to achieve in pure hydrogen storage.

          Let's assume a density of 700 kg/m^3 for our liquid hydrocarbon. According to Wikipedia (again), gasoline is around 737 kg/m^3. Let's further assume that hydrogen makes up about 15.8% of the weight of our fuel. I arrived at that number by doing a straight average of the percentages for C5 to C12 linear alkanes. That means the part of the density we can attribute to usable hydrogen is around 111 kg/m^3.

          So, in terms of effective hydrogen density, liquid hydrocarbons beat the pants off of even pure liquid hydrogen.

        • Re: (Score:3, Informative)

          by Mspangler ( 770054 )
          My version, which is only slightly modified;

          Step 1: Generate pure hydrogen in highly efficient processing plant
          Step 1A: Remove CO2 from air and reduce it to carbon in a highly efficient processing plant.
          Step 2: Merge with carbon to create lower density hydrocarbon based fuel called methanol.
          Step 3: Use existing liquid fuel transport system to ship methanol.
          Step 4: Use methanol fuel cell to the power the car, producing CO2 and H2O
          Step 5: $$$, at least compared to hydrogen fuel cycles.

          If methanol is good enou
        • Re: (Score:3, Informative)

          Personally I think guys are on the right track, even if they aren't there yet. http://www.asemblon.com/hydrnol [asemblon.com]. I've talked a little to a couple of them and they have a liquid organic carrier that can release H2 under reasonable conditions using a catalyst. The carrier can then be rehydrogenated for reuse. The carriers supposedly easily produced and the net energy is pretty good.
      • Re: (Score:3, Insightful)

        by h2_plus_O ( 976551 )

        You fuel at a station, but instead of just filling up with hydrocarbon (like we do now), you also give back the carbon that your car's been storing.

        ...so if you're going to reform hydrocarbon fuel to yield hydrogen, why do that on board the vehicle instead of simply having the vehicle take hydrogen as its fuel? If carbon capture and sequestration is anything but a pipe dream to begin with, it will be a damn sight easier to engineer without the added constraints of having to fit onboard a motor vehicle.

    • FTA:

      Georgia Tech's near-future strategy involves capturing carbon emissions from conventional (fossil) liquid hydrocarbon-fueled vehicles with an on board fuel processor designed to separate the hydrogen in the fuel from the carbon. Hydrogen is then used to power the vehicle, while the carbon is stored on board the vehicle in a liquid form until it is disposed at a refueling station.
      • So, let me get this straight. We are going to exchange CO2 emissions (a greenhouse gas) for H2O emissions (another greenhouse gas). In the meantime, we are going to have to consume more energy to accomplish it. I'm sorry, something about this equation doesn't add up.
        • by g1zmo ( 315166 )
          How is water a greenhouse gas?
          • Re: (Score:3, Informative)

            by timmarhy ( 659436 )
            your comment is typical of all global warming idiots, you don't even understand your own imaginary problem.

            water vapour is THE green house gas. the majority of the greenhouse effect comes from water vapour. hence why everyone is trying to tell you people CO2 doesn't drive climate change.

            • by eln ( 21727 )
              The argument is not that CO2 is causing global warming, it's that the increase in the amount of CO2 in the air is driving global warming. Yes, water vapor is the most abundant greenhouse gas, but the amount of water vapor in the air hasn't been steadily increasing over the past hundred years, while the amount of CO2 in the air has been. I suppose it's possible that a mass conversion from hydrocarbon fuel to hydrogen which emits water vapor as waste could end up being just as bad for the global climate as
              • Re: (Score:3, Insightful)

                by cplusplus ( 782679 )
                Water molecules also have a tendency to clump and fall to the ground. Carbon dioxide molecules don't. A massive increase in precipitation would probably affect things in detrimental ways.
                • Re: (Score:3, Interesting)

                  by sumdumass ( 711423 )
                  An increases in water vapor doesn't automatically mean an increase in precipitation. You can look at the dew points and see how this is possible. and yes, there has been more water vapor in the air as of late. This could be an effect or a drive in the global warming that we know but it could also mean that the Co2 model is coincidentally pointless.

                  It is a toss up if you ask me, the amount of Co2 that is claimed to be the problem is less then .001% of the total green house gases in the atmosphere at any give
                • Re: (Score:3, Insightful)

                  by apoc.famine ( 621563 )
                  Outside my house it is currently 21 degrees F. When I discuss with my students the potential of using hydrogen as a clean fuel, as it releases only water vapor as a byproduct, they generally realize that there is another issue with it other than greenhouse gas emissions. In a good portion of the world, there is this thing called winter. A massive increase in water vapor on roadways when the temp is below freezing is not necessarily a byproduct that many people think of when debating a hydrogen infrastructur
            • Re:Hydrogen? Carbon? (Score:5, Informative)

              by sectionboy ( 930605 ) on Thursday February 14, 2008 @07:19PM (#22428512)
              I might be one of "global warming idiots" - for not knowing too much about it, but I failed to see how water is as bad as CO2 in this issue. Earth, as we know, has 3/4 of its surface covered by water, thus the atmosphere is basically saturated for water vapour, i.e., no matter how much water (liquid, vapour, ice, all forms combined) exists on this planet, the amount of water vapour in atmosphere as a whole system is almost constant as long as the climate (temperature, pressure) doesn't change dramtically.
            • by g1zmo ( 315166 )

              I didn't know I had a problem -- real or imaginary. I don't know anything about global warming, but if you wanna call me an idiot across the internet I guess I'm fine with that. I was asking because I'm no scientist and I've never heard of water referred to as a greenhouse gas. I took physics and chemistry in high school, but that's pretty much the extent of my knowledge of atmospheric dynamics.

              You, however, seem to have a rather large chip on your shoulder.

            • Re: (Score:2, Informative)

              by Anonymous Coward
              Water vapor is A greenhouse gas. Any gaseous molecule with an IR/microwave spectrum will trap heat and act as a greenhouse gas if it's present in a large enough quantity. The nice thing about water is that it reaches an equilibrium vapor pressure when all else in the atmosphere is equal. So at our current temperatures on earth, it's hard to saturate the atmosphere with more than just a little bit of water (a few percent). However, pumping CO2 into the atmosphere adds another greenhouse gas and upsets th
            • by Jeremi ( 14640 )
              your comment is typical of all global warming idiots, you don't even understand your own imaginary problem. water vapour is THE green house gas. the majority of the greenhouse effect comes from water vapour. hence why everyone is trying to tell you people CO2 doesn't drive climate change

              And ironically enough, your comment is typical of all the global-warming-denial ostriches: You're so sure that global warming is a hoax and that anyone who takes it seriously is an uninformed fool that you don't see the gl

          • Re: (Score:2, Interesting)

            Water is the one of the best green house gases.
            It's absorption of IR is a lot higher then CO2.
            Water vapour carries a lot of energy as well to drive extrem weather effects.

            On the plus side clouds do help reflect sunlight.

            handy link
            http://www.lsbu.ac.uk/water/vibrat.html [lsbu.ac.uk]
            • by Rei ( 128717 )
              And it only stays in our atmosphere for a couple days on average thanks to preciptation ;) Hence, water vapor can only function as feedback, not forcing.
              • No, well. yes and no. It would be a feedback no matter how you looked at it because it isn't a driving source. Solar energy being the most common alternative to Co2. But water vapor can stay in the atmosphere quite a bit longer then a couple days. And the atmosphere can hold different amounts of water. It isn't a static operations. You can look at the differences in the dew points to find increased relative humidity even in a drought.

                So no, it isn't a static number that only saturates to a point and then di
                • by Rei ( 128717 )
                  No, well. yes and no. It would be a feedback no matter how you looked at it because it isn't a driving source. Solar energy being the most common alternative to Co2. But water vapor can stay in the atmosphere quite a bit longer then a couple days.

                  The average is about ten days [realclimate.org]. Remember the word "average" in my post? That word has meaning.

                  "To demonstrate how quickly water reacts, I did a GCM experiment where I removed all the water in the atmosphere and waited to see how quickly it would fill up again (thr
                  • And again, yes and no.

                    The problem is that humidity, or the amount of water in the atmosphere isn't constant. There isn't a set normal. There is simply a level that can be used as a baseline and and measurements can be made either way from it. That page doesn't attempt to do anything of the sort, it attempts to say that X is normal and correlate that to all the interactions within the atmosphere. The problem with this is that there is no normal X. It varies due to temperature and numerous other factors. 70%
          • I guess it has something to do with water being a good absorber of long-wave infrared. Maybe our friends at the wikipedia [wikipedia.org] can help explain that.
        • Yes H20 is a greenhouse gas in that it traps heat, but the amount of water vapour in the atmosphere is a function of temprature and pressure. In other words the H20 content of the atmosphere is stable. The only side effect of releasing 10Gt/pa of water vapour would be 10Gt/pa more rain (good thing if it all fell here in SE Australia).

          The side effect of releasing the current 10Gt/pa of CO2 is that 7Gt of it will not be absorbed back into the biosphere. Some of it stays in the atmosphere and heats things u
    • by goombah99 ( 560566 ) on Thursday February 14, 2008 @05:27PM (#22427084)
      I think what they are after is a carbon source liquid that releases hydrogen and traps the carbon. THis is presumably to get around the low density of pure hydrogen storage. Perhaps some sort of fuel cell that liberates hydroggen from methane, keeps the carbon and burns the hydreogen. just a guess. low density is a problem both for the cars and for the fueling stations. to top it off liquid handling is easier than gas phase for consumers.

      But there's an israeli company with an even better idea.

      You use solid magnesium and water. the magnesium a spool of wire that is fed slowly into a bath of water. it reacts to produce hydrogen which bubbles out and into the engine, and also a solid magnesium oxide which sinks and is collected. THe solid magnesium waste is collected, and sent to a plant where it reproccessed back to magnesium metal electochemically, releasing oxygen in the process which itself could be collected for other uses.

      • by goombah99 ( 560566 ) on Thursday February 14, 2008 @05:30PM (#22427128)
        Link [physorg.com]. also google for magnesium hydrogen car and you'll also find other companies.
      • by blair1q ( 305137 ) on Thursday February 14, 2008 @05:40PM (#22427268) Journal
        And where do they get the electricity to reprocess the Mg02?

        From an oil- or coal-burning power plant, of course.

        Or a nuke plant.

        These ideas of using renewable chemical fuels is all pretty silly, because they all use electricity to renew the fuel. But electric vehicles are efficient, viable, can be made attractive and fast, and they cut out the middle-man by allowing you to plug into a supply of electricity you already access. No infrastructure cost = lowest economic barrier to entry. And it's infrastructure that we have 150+ years of experience maintaining and improving.

        Eventually all of our energy will be delivered from electrical utilities, generated from coal (the oil will run out soon but we have several hundred years' worth of coal left), nuclear processes (about a thousand years' worth), and the sun (several billion years, but it's terribly inefficient so far).
        • But electric cars need to run off of batteries, and batteries are very bad at storing energy. They also take too long to recharge. They've tried pushing electric cars on the market and they were pushed right back off. I take road trips of over 300 miles every couple of months, and there's no way that an electric car would be able to make it in the same time period that my gas car can.
          • Re: (Score:3, Funny)

            by blair1q ( 305137 )
            Batteries are cheap and less inefficient than the Otto cycle engine in your car.

            As for charging times, you can charge it when you're sleeping.

            Long-distance travel will take a major hit when the oil runs out. There's nothing to use as jet fuel that's as good as jet fuel. That's why it's jet fuel.
            • As for charging times, you can charge it when you're sleeping

              There are no convenient outlets near my apartment building.

              Long-distance travel will take a major hit when the oil runs out

              Which won't be for a long, long time, certainly not in the next few decades. Oil wells are still putting out a lot, when they're out there's a lot of shale laying around in Canada and the US, then there's the ability to extract it from coal. Oil's going to be around for a while.

              • by Jeremi ( 14640 )
                Oil wells are still putting out a lot, when they're out there's a lot of shale laying around in Canada and the US, then there's the ability to extract it from coal. Oil's going to be around for a while.

                That's true, but it's not enough for oil to exist. It has to also be cheaper than the alternatives. How cheap will a gallon of gas be when you have to extract it from shale? How cheap is it after we've factored in the cost of global warming damage? What's the price of a gallon of gasoline if you add in th

    • I was thinking the same thing. I thought burning Hydrogen and Oxygen produced primarily water.
    • The car runs on hydrocarbons, but instead of burning them it pulls the hydrogen out and burns that, leaving carbon-rich goop. If the hydrocarbon was, for example, methane (CH4) this would seem to be pretty cool, because it would allow us to burn it without any CO or CO2 being fed off into the atmosphere.

      They're probably not thinking methane though, because methane is annoying to transport, same as Hydrogen.

      As you move down the scale toward bigger, more likely to be liquid molecules, however, you move toward
  • I thought (Score:4, Insightful)

    by Altus ( 1034 ) on Thursday February 14, 2008 @05:19PM (#22426964) Homepage
    There were already some pretty good ways of storing hydrogen for cars and the issue was just creating the hydrogen in the first place.

    Seems like using hydrocarbons and storing liquid carbon in the car for later processing would be a real pain for very little gain. Though maybe this would be a good way to get hydrogen to the "gas station."
    • Re:I thought (Score:5, Informative)

      by ciggieposeur ( 715798 ) on Thursday February 14, 2008 @05:34PM (#22427186)
      There were already some pretty good ways of storing hydrogen for cars and the issue was just creating the hydrogen in the first place.

      Not really. The Department of Energy has estimated that one would need at least a device capable of storing up to 0.6 kg of hydrogen per kg (e.g. a 100kg storage tank has 6kg of raw hydrogen in it) before hydrogen is just barely usable as a transportation fuel source. Ideally, 12% wt/wt storage is necessary to achieve the 300 miles per tank that most cars get today on gasoline. The best storage systems (circa 2004 when the report came out) topped out around 8% for liquified hydrogen tanks, but those are very difficult to use in practice because the hydrogen leaks out quickly. All other systems topped out around 4% and required either high temperature (metal hybrides) or very high pressures (700bar, approximately 10000 psi), again making them not yet ready for widespread use.

      Hydrogen production is still an issue too though. Most of what we get now is a byproduct from natural gas processing, so it's still not carbon-neutral.

      (Disclaimer: This topic is actually part of my master's thesis.)
      • by Altus ( 1034 )

        I remember something about tiny ceramic beads... with micro perforations, helping to hold more hydrogen without leakage. It was a while ago that I saw this though.

        Clearly production is the big issue, but these guys are talking about harvesting hydrogen from a hydro carbon right in your car. If you can do that, why not do it somewhere else where you can more easily store, or reprocess the carbon.

        I'm certainly no expert on this topic but the articles description makes this seem like an excessively complicat
  • by victorvodka ( 597971 ) on Thursday February 14, 2008 @05:21PM (#22426992) Homepage
    Here's why: hydrogen takes enormous amounts of energy to make. Stop saying that when you burn it all you get is water; in the case of a hydrogen economy, all the polluting happens in the supply chain, although it can also manifest in more direct forms such as a hydrogen car plowing into a container full of pesticides. Another thing: hydrogen cars are just a distraction to allow car manufacturers to keep kicking the ball down the road on producing a truly fuel-efficient car, one far more modest than the one you're presently driving. Get used to it people; when peak oil rolls through, that moped that was "fun to ride until your friends saw you" (much like a fat chick) is going to look like Fonzie cool. Rent "Who Killed the Electric Car" to learn more. http://en.wikipedia.org/wiki/Who_Killed_the_Electric_Car%3F [wikipedia.org]
    • There are plans to produce hydrogen directly from the thermal output of a nuclear reactor using the sulphur-iodine process, so if you want no carbon emissions, it will be possible. It's possible now, just more expensive than using natural gas.
    • by dgatwood ( 11270 )

      Hydrogen cars are just a distraction to keep people from noticing how absolutely horrible auto manufacturers' electric concept cars are. Case in point: the Chevy Volt. I saw an ad for this last night. Up to 40 miles without using gasoline. Oh, yeah. That will barely get me to work and back, and I live one town away. Want to go on a longer trip? You're back to gas guzzling. Worse, you have all the weight disadvantages of hauling around a gasoline powered engine, which means you're far less efficient

      • Re: (Score:3, Insightful)

        I've been looking at the Volt too. The thing with it it seems that technically it's a hybrid, but the motor they're talking about putting in it would be far too small to be able to drive around on. It would be more like a gas powered battery charger, you'd have to let it sit for a while in the parking lot running to get you enough battery power to make it home, if in the city, or to be able to get up to speed on the highway and then it could keep up once the load dropped and you were cruising.

        Personally

        • by FroBugg ( 24957 )
          You seem to misunderstand the Volt somewhat.

          In a current hybrid car, like a Prius (even the ones modified to work as plug-hybrids), the electric and gasoline motors work in parallel. Either can run to move the car. In the Volt, they run in series. The gasoline motor only provides electricity. This means that it never has to run at high RPM and is always operating at its peak efficiency. The electric motors used to actually propel the car are efficient enough to take the electricity generated by the motor an
    • Rent "Who Killed the Electric Car" to learn more.

      Or, if you want a more productive way to spend an hour and a half of your life, go run head first into a wall.

      Market demand killed the electric car. These conspiracy theories are no better than the claims that "big oil" is suppressing conventional engines which could get 100 miles per gallon (and violate the laws of thermodynamics, all in one stroke!).

      The rest of your comment was actually quite insightful, it's just too bad you had to end it with tha

  • by RobertB-DC ( 622190 ) on Thursday February 14, 2008 @05:25PM (#22427052) Homepage Journal
    From TFA:

    The Georgia Tech team has already created a fuel processor, called CO2/H2 Active Membrane Piston (CHAMP) reactor, capable of efficiently producing hydrogen and separating and liquefying CO2 from a liquid hydrocarbon or synthetic fuel used by an internal combustion engine or fuel cell. After the carbon dioxide is separated from the hydrogen, it can then be stored in liquefied state on-board the vehicle. The liquid state provides a much more stable and dense form of carbon, which is easy to store and transport.

    I don't know what planet they were planning to use these vehicles on, but on *this* one, CO2 is a GAS. You've got to have some serious refrigeration (requiring, uh oh, ENERGY) and some darned high pressure to store liquid CO2. Laws of thermodynamics aside, I'd rather not be sitting on a mobile dry ice bomb [dryiceinfo.com], thankyouverymuch.

    A side note: the original tag for Roland articles was "pigpile", not "ohnoitsroland" (or any of the cruder variants). Piquepaille = Pigpile, get it? And it's usually an apt description of the science behind the "discovery".
    • I believe the plan is to combine the CO2 with the Hydrogen's steam emissions and a box of concentrated syrup of Mountain Dew.
    • Piquepaille = Pigpile, get it?

      Yes, originally it did. But it was deemed offensive to pigs everywhere and is, therefore, no longer in common use.
    • You've got to have some serious refrigeration (requiring, uh oh, ENERGY) and some darned high pressure to store liquid CO2.

      Refrigeration has nothing to do with it. At standard pressure, cooling CO2 just causes it to solidify. To get liquid CO2 you must increase the pressure by quite a bit, but again, no refrigeration is required.

      Laws of thermodynamics aside, I'd rather not be sitting on a mobile dry ice bomb, thankyouverymuch.

      I have several CO2 tanks sitting in my garage for serving beer. These co

    • by pla ( 258480 )
      I don't know what planet they were planning to use these vehicles on, but on *this* one, CO2 is a GAS.

      Ever seen dry ice?

      Or, for that matter, a fire extinguisher? CO2 has a liquid phase at pressures above 5.1 atmospheres - A fact that some of the earliest fire extinguishers (and a few modern ones) made use of to store their charge at ordinary ol' room temperature.



      You've got to have some serious refrigeration (requiring, uh oh, ENERGY) and some darned high pressure to store liquid CO2.

      No, pressur
      • I don't know what planet they were planning to use these vehicles on, but on *this* one, CO2 is a GAS.

        Ever seen dry ice?

        C'mon, he's obviously talking about CO2 at STP.

        No, pressure alone will suffice - And internal combustion engines excel at producing just that.

        I'd love to see the efficiency cost of tapping an engine to produce pressurized liquid CO2 from the hot CO2 exhaust out of an internal combustion engine. I can't find the specs on a CO2 compressor offhand. Regardless, I imagine it ain't pretty.

        In fact, every other form of energy they produce requires the conversion of pressure into something else.

        Now you're just being ridiculous. There's no simple way to run an efficient compression system directly off the combustion expansion cycle of a conventional piston-driven engine. Given the thermal isolation needs plu

  • For those of you who scratched your head at the summary and title:

    The car _is_ hydrogen powered, sorta. However, it generates the hydrogen on-board from a hydrocarbon fuel. The hydrogen is then used to power the vehicle, and the leftover carbon remains in the car, and is taken back to a central location for disposal.

    Apparently, they are able to create H2 + liquid CO2 using a special CO2/H2 Active Membrane Piston (CHAMP) reactor. The liquid CO2 is never released to the atmosphere.
  • The summary is incredibly poorly written. Essentially the cars extract the hydrogen from hydrocarbons and store the carbon leftovers in a tank. This is a poor idea as not only is extracting the hydrogen inefficient, you're only using a minority of the mass of the fuel to power the car and worse, you're transporting the waste around with you, then shipping it back to a processing plant where more energy will be spent making it usable. You waste so much energy throughout this process and you're using non-ren
  • ohnoitsroland (Score:3, Informative)

    by Aaron Isotton ( 958761 ) on Thursday February 14, 2008 @05:28PM (#22427096)
    Roland obviously botched the summary. It's not about hydrogen powered cars as in "cars in whose tanks you put hydrogen", but about hydrogen powered cars as in "cars with conventional fuel in the tank, which then gets split into hydrogen and carbon, and the hydrogen is used in the engine". TFA is actually interesting.
    • by dbIII ( 701233 )

      Roland obviously botched the summary

      I for one am looking forward to this wonderful liquid carbon!

  • I can't believe this kind of schlock is getting any attention at all. This is so stupid and impractical that I don't even know where to start.

    Here is what they are proposing:

    1. Capture the exhaust
    2. Pull the hydrogen (?) out of the exhaust
    3. Run the car from the hydrogen
    4. Dispose of the carbon somewhere.
    5. Eventually re-use that carbon somehow to make new fuel.

    These people are morons. How much hydrogen is there in emissions? I doubt enough to run a car.

    I swear, the public press is so desperate for f

    • No, what they are proposing is:

      "The Georgia Tech team has already created a fuel processor, called CO2/H2 Active Membrane Piston (CHAMP) reactor, capable of efficiently producing hydrogen and separating and liquefying CO2 from a liquid hydrocarbon or synthetic fuel used by an internal combustion engine or fuel cell. After the carbon dioxide is separated from the hydrogen, it can then be stored in liquefied state on-board the vehicle. The liquid state provides a much more stable and dense form of carbon, whi
  • I love to be captain obvious, so why are the cars separating the hydrogen from the carbon and storing the carbon? Why don't they separate it at a central plant, then ship the hydrogen to the fueling stations? Then the car wouldn't have to carry all that extra carbon around and they fueling stations wouldn't have to send the carbon back to be stored somewhere. - SuckItDown!
  • by Radon360 ( 951529 ) on Thursday February 14, 2008 @05:36PM (#22427224)

    1. Fill up with regular gasoline
    2. Instead of burning it outright, let's strip the hydrogen off the hydrocarbons and just burn that.
    3. Somehow sequester the leftover carbon from the breakdown (this is the ???? step)
    4. Return the carbon (somehow stored in liquid form) for recycling >>> Profit!

    First, let's ignore how much energy we're throwing away in step 2 by not utilizing the full energy potential stored in the hydrocarbon molecules. Second, somehow we'll expend more energy to liberate the hydrogen and capture the carbon, both without oxidizing them. Third, we're going to tote around another 75 - 100 pounds of weight with the stored (and somehow liquefied) carbon that will be returned. Less energy potential that ever reaches the engine/fuel cell, and even more expended to refine something fairly energy dense into something that's a fair amount less energy dense.

    The problem with this idea is there's too much fixation on sequestering every last bit of carbon, rather than focusing on a bigger, more important concept called energy efficiency. Work on improving that and the carbon emission reductions usually follow.

    • You're missing the best part! We can build some pressure cookers into these cars to compress the released carbon into diamonds, and then we can win girls hearts, or sell them off at a profit to buy more gasoline! Even it we don't get diamonds out of it, maybe we can make graphite pencils and then drop a load off at the nearest school. Think of the Children! Sure, maybe the four-wheeled diamond manufacturers will drive nice companies like DeBeers out of business and destablize the paradise that is South
  • A commenter on Greentech Media points out that this research is mostly NASA and DOD funded [greentechmedia.com].
  • by edwardpickman ( 965122 ) on Thursday February 14, 2008 @05:42PM (#22427308)
    There's a British company trying the same thing the article is confusing but the system essentially spilts off the hydrogen inside the vehicle then stores the carbon from hydrocarbon fuel. They reprocess the stored CO2 back into a hydrocarbon fuel so it's a closed loop system. It's more a way to store hydrogen as a hydrocarbon then recycle the storage medium, the carbon. It's in no way a fuel source it's a storage medium. ALL hydrogen based systems are storage mediums not fuel sources. Hydrogen is too friendly about combining with other elements so the hydrogen always needs to be spilt off to use as fuel. I take it you can store a lot of hydrogen safely this way if the system can ever be perfected but the real point is there's little difference from an electric vehicle other than faster refueling. Because of transfer losses I have to believe it's less efficent than straight electric. Even hydrogen cars are generally all electric so the hydrogen largely replaces batteries. Because of all the technical problems it seems focusing on improving batteries would be a better solution. There's no proof this system is in anyway practical let alone the technology still doesn't exist.
  • Finally something good to come out of France in awhile.

    A better and cleaner solution is the "Air Car" [theaircar.com]. Powered by compressed air.

    The prototype [businessweek.com] is supposed to travel up to 150 miles off one fill up with a top speed of 60 mph.

    When they hit final production, I think I'll be buying one just so I can laugh my ass off as I pass every gas station.
    • And I'll be laughing when your car gets turned into free-floating molecules by a collision with some guy's family Van.

      Seriously, that vehicle has such low mass, low cargo carrying capacity, and poor performance, that you may as well go buy yourself a scooter instead. It might be an ok vehicle for booting around the downtown core of a major metropolis (in which case you could make a decent business using them as taxi-cabs, or renting them to tourists) but you wouldn't catch me trying to take one of those de
      • Putting around town is about all I'd do in it anyway. I drive on the highway maybe less than 3% of the time I spend driving annually.
  • Is this a study to see how energy *inefficient* a vehicle can be over its lifespan? From manufacturing these vehicles, to the fact that they still take in fossil fuels, to hydrogen giving you not "zero emissions" but water vapor (which functions as a greenhouse gas), to liquid CO2 being stored on-board and then... under an ocean hahah. Car manufacturers would have to be out of their freaking mind to ever go along with this ridiculous idea.

    This is all such a BAD IDEA that I'd probably have been happier to re
  • In this case hydrogen is not an energy source, it is an energy storage medium. Just a high density "battery". You still need to generate massive energy to make the hydrogen and you've added yet one more step that makes they whole precess a looser (http://en.wikipedia.org/wiki/EROEI). Furthermore, no one is sure if carbon sequesteration will really work and if it does work it will generate more green house gases go move the carbon and and ram it into the earth than it will sequester.

    The solution is to d

  • Although the article claims it does not mix the hydrocarbon fuel with air, it must do so to produce the hydrogen. Oxygen is a key ingredient to converting a hydrocarbon fuel into hydrogen and carbon diOXIDE. Where's the oxygen coming from in this system?
  • is apparently not a precursor for babbling on about energy schemes

    all hydrogen fuel schemes are idiotic

    it takes more energy to convert any fuel source to hydrogen. unless the hydrogen is found naturally, or is the byproduct of some other industrial chemical process, there is zero sense in converting any energy source to hydrogen, simply because you waste so much energy doing that. translated: hydrogen isn't green

    solution: more nuclear plants, electric cars. get with the f***ing program
  • Hydrogen, Bio-Fuel, etc. are all a waste of time, money, energy, and a blind alley. We have the solution to our energy crisis. It's called Solar Power. Solar panels continue to get more efficient and fall in price. This is a process that would accelerate if we bought more of them. This coupled with cars modeled on the Tesla design would be the fastest and easiest way to upend are oil based economy, and then eventually driving would drop much nearer to the price of free as well.

    Of course automakers, oil
  • ...desire.

    There's an even better way to separate the hydrogen and carbon. Burn it. :-)

    Eample: C7H16 + 22 O2 = 7 CO2 + 8 H20

    Yeah, your C and H gets all mucked up with that nasty O, but there ya go.

  • by BUL2294 ( 1081735 ) on Thursday February 14, 2008 @06:43PM (#22428094)
    Seriously, with this plan, we will have cars that shit!!! I can see the "Cousin Eddie"s of the world standing in the cold with hoses, dumping the carbon sludge down the local storm sewer--while smoking cigars. "Car wouldn't go--shitter was full!"
  • by EricBoyd ( 532608 ) <mrericboyd@y a h o o.com> on Thursday February 14, 2008 @07:17PM (#22428478) Homepage
    I've had enough of all the hydrogen hype, slashdot should run more stories on the Autmotive X Prize. For which hydrogen is not an acceptable fuel. Check out the X Prize Cars [xprizecars.com] - and we're still 2 years from the race yet!
  • I think a better solution would be to carry that algae stuff they are testing on coal power plants now and use it in our vehicles. Since fuel cells produce the two primary ingredients anyways. Water, and CO2.

    Basicall, we'd be producing biodiesel while we drive. We'd get a tax credit in return for our continued donations of carbon growing algae. Granted this wouldn't pull out all the carbon we produce. But it might come close enough to pay for itself or damn close to carbon nuetral.
  • This type of closed-cycle system is a method to store and transmit energy.

    So what's missing?

    An energy source. Where is all the energy going to come from?

"The whole problem with the world is that fools and fanatics are always so certain of themselves, but wiser people so full of doubts." -- Bertrand Russell

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