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Science Technology

CO2 To Fuel, Closing the "Carbon Loop" 316

leprasmurf writes "Inhabitat has posted an article detailing a recent announcement of a process to turn CO2 into fuel. The process, which used to be considered too energy inefficient, uses a multi-step, low pressure, and low temperature biocatalyst to break the CO2 into 'basic hydrocarbon building blocks.'"
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CO2 To Fuel, Closing the "Carbon Loop"

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  • by el_chupanegre ( 1052384 ) on Monday October 13, 2008 @06:09PM (#25362089)

    Funnily enough there was a program on TV here in the UK last night about producing electricity from CO2 and water.

    Two guys in the New Mexico desert had a huge mirror array the focussed the sun into a really intense beam (they could melt steel with it) and directed it into a giant furnace, which I think got to 2400 degrees C, but could have been 4200. This heated the air inside to separate the CO2 which they could then use to create hydrocarbons.

    This all worked on a huge scale of course, but they also had a smaller version that could produce 2-3 gallons of fuel a day that was about the size of a pretty young small tree.

    So I agree that the energy has to come from somewhere in order to separate the CO2, but who says that energy can't come from solar power eventually? Of course this is more expensive now, but it'll be getting cheaper all the time as oil gets more expensive.

  • by jmichaelg ( 148257 ) on Monday October 13, 2008 @06:17PM (#25362167) Journal

    Last February, Los Alamos announced they had a process that converts CO2 to gasoline. [lanl.gov] The associated white paper proposed using a nuclear reactor to provide the requisite energy to drive the process. They went as far as to estimate the costs of their process and pegged the cost of gasoline at $4.30 gallon at the pump. A significant fraction of their cost estimate was credit costs to finance the plant. They figured 50 cents for every dollar sales given the billions they'd need to start the process. Without factoring the credit costs (which they could do if they could convince enough investors to take an equity position instead of borrowing the capital) they estimated their process produced gasoline at $1.40 per gallon.

  • by telchine ( 719345 ) on Monday October 13, 2008 @06:20PM (#25362199)

    Where the f**k do people find these brain-impaired investors? Why can't I find them? I can make snake oil, po sweat. I can tell people everything they want to hear. I can make up ridiculous unbelievable stories with no problem at all! Hell, I can do even better. You want infinite energy??? I can give you infinite energy * 2! That's twice as good even our best conmen competitors! Surely if the whole of Slashdot were to team together we could make a fortune with these wacky ideas!

    What is it that makes it possible for these kind of people to have investors fawn at their feet whilst the rest of us have problems getting investors to believe in the basic laws of physics?

  • by AshtangiMan ( 684031 ) on Monday October 13, 2008 @06:25PM (#25362255)
    I think it's interesting that these guys are collecting a LOT of energy and using it to make fuel, that is then burned to create energy. That's a couple of conversions. If they are able to melt steel, why not then melt salt and use the big bucket of molten salt to drive a steam turbine that generates electricity? I'd be willing to bet that in the end they would end up with more usable energy per unit time.
  • Ammonia (Score:3, Interesting)

    by mgv ( 198488 ) <Nospam.01.slash2dotNO@SPAMveltman.org> on Monday October 13, 2008 @06:28PM (#25362291) Homepage Journal

    There are two issues here.

    The first - energy. It cant be avoided. To make fuel from CO2 you need energy. Nuclear, wind, solar. It doesn't matter what really, but you will need some input and this technology cannot address that.

    The second - why do this. Actually, it makes sense to have a liquid fuel base. Transportation runs on liquid fuel as a store of energy. If we make liquid fuels from solar, for example, we can store solar energy in a useful form for when it is dark.

    So without commenting on this particular technology - which everyone has quite rightly stated won't work without considering energy inputs - the general concept of creating a liquid fuel energy store has some merit.

    Having said this, I've spent quite a bit of time looking at a rather different liquid fuel store which I think has more promise than hydrocarbons.

    That fuel is ammonia.

    Whilst its only half as energy dense as diesel [wikipedia.org], its not that hard to make from electricity. In fact, it can be made by electrolysis fairly easily, and this has been done for nearly 100 years. [wikipedia.org] so its not exactly new technology.

    Nor is the ability to use it in a standard internal combustion engine. In fact, it was being used as a fuel for buses over 60 years ago [ammoniafuelnetwork.org] and it works in a standard engine with little modification.

    Because its less energy dense than diesel, its a lot easier to make synthetically, but has enough energy per litre to be worthwhile. Whilst having half the range per litre of fuel is an inconvenience, I am sure that we could live pretty much as we do today with vehicle technology that is available today.

    We either accept half the range, or build the fuel tanks twice as big, or maybe even make the cars twice as efficient. All of these are easy options really.

    I think that we have all gotten so fixated on fossil fuels that we have ignored a really low technology solution here.

    Michael

  • by hanssprudel ( 323035 ) on Monday October 13, 2008 @06:29PM (#25362297)

    Carbon Sciences has developed plans for a CO2-Fuel transformation plant that takes CO2 from a large emitter, such as a power plant, and produces usable fuels as the output.

    In case you missed it, that would be when you know this is nonsense.

    (By the laws of nature, getting the carbon out of the CO2 will take at least as much energy as you got by burning the carbon in the first place. So attaching the "transformation plant" to a carbon fueled power plant means you have a process turning hydrocarbons into hydrocarbons, and spending energy doing it.)

  • by Anonymous Coward on Monday October 13, 2008 @07:03PM (#25362641)

    You cannot hide from the chemistry.
    The energy to do this MUST come from *SOMEWHERE*.

    Well, duh. That's not the point. The attractiveness of such a process is that we have a world built around hydrocarbons, we're running out of fuel, the climate is taking offense at all the CO2 in the atmosphere and there is a giant fission reactor 1AU from here which constantly delivers a huge amount of energy to us (but we haven't yet found a way to store that energy). If you could use the energy from the sun to turn CO2 back into usable fuel, that would solve quite a lot of problems in one go.

  • Re:SCAM (Score:3, Interesting)

    by cgenman ( 325138 ) on Monday October 13, 2008 @07:18PM (#25362799) Homepage

    They're intentionally masking their whois domain information. According to Popular Mechanics, they can make toothpaste. [popularmechanics.com]

    Very confusing. Why not just tell us what the base energy source is? Otherwise, it's just a perpetual motion machine.

  • by hobbit ( 5915 ) on Monday October 13, 2008 @07:30PM (#25362887)

    Not necessarily; see http://en.wikipedia.org/wiki/Polywell [wikipedia.org]

  • Re:Vaporware alert (Score:5, Interesting)

    by sortius_nod ( 1080919 ) on Monday October 13, 2008 @08:30PM (#25363381) Homepage

    Indeed, they are a counted as a weed here in Australia... they ruin creeks and rivers by upsetting the balance of the ecosystem (dominate over natural grasses and trees).

    So yes, GP needs to check their facts first.

  • Re:Wake up, folks (Score:3, Interesting)

    by jeff4747 ( 256583 ) on Monday October 13, 2008 @08:49PM (#25363543)

    Question: If it costs 20 units to regenerate the original 10 units, why not just use the 20 units and forget about regenerating the original 10?

    Storage and transport.

    Let's say your 20 units of energy come from a nuclear power plant. I can't strap one of those onto my car. Battery technology doesn't currently provide enough energy density, and there's a significant amount of energy lost as heat over the power grid.

    OTOH, we make a liquid hydrocarbon out of the energy, we get very little "line loss" during transport of the energy to my vehicle. And the energy density is high enough to be practical in a car without sacrificing range.

  • Re:Ammonia (Score:4, Interesting)

    by Mr. Roadkill ( 731328 ) on Monday October 13, 2008 @08:50PM (#25363559)

    That fuel is ammonia.

    You know, from a safety standpoint, twenty years down the road I'd rather have a couple of hundred thousand clunkers on the road running LNG or ethanol or biodiesel or whatever than ammonia. Ammonia probably makes a lot of sense for well-maintained fleets - and its safety record in refrigeration and agricultural applications is pretty good - but I'm not sure I'd like it used as a regular transportation fuel by Joe Public in his poorly-maintained car. I suspect there would be concerns from those who service vehicles, too - a whiff of leaking hydrocarbon fuels isn't something that's likely to put you in hospital.

  • by mathmathrevolution ( 813581 ) on Monday October 13, 2008 @09:54PM (#25364069)
    I saw the Green Freedom developer, Dr. Jeffrey Martin, give a talk at Georgetown. His process is already really efficient. As I recall the GF process to convert CO2 into fuel was within a factor of 7 of the theoretical minimum energy required which compares well even to biological processes. I'm skeptical that the magic proprietary "Biocatalytic Reactors" Inhabitat has developed could be significantly more efficient, especially since no numbers whatsoever are provided. Yellow Flag: Inhabit doesn't even claim to have a patent pending on their "breakthrough" process. Green Freedom has at least a few real patents in the works.
  • by ChrisMP1 ( 1130781 ) on Monday October 13, 2008 @10:00PM (#25364119)
    16(CO2) + 18(H2O) -> 2(C8H18) + 25(O2)
    Just add water.
  • Re:Vaporware alert (Score:2, Interesting)

    by tomatensaft ( 661701 ) <tomatensaft AT gmail DOT com> on Tuesday October 14, 2008 @03:27AM (#25365847)
    Oops, modded you wrong. Never knew, that willows were actually detrimental to Australian ecosystems...
  • by stoev ( 103408 ) on Tuesday October 14, 2008 @04:36AM (#25366125)

    So the article is misleading. But can we extract some use of it?

    I am not working in this area, but this is what I understand: We have CO2. We want to convert it to H2-C-H2 groups and bigger molecules + O. This requires energy, sure. Maybe in form of high temperature... So we need heat.

    Here is my suggestion: there are large amounts of unused heat in power plants - both conventional and nuclear. This is why you see all these tubes and white smoke near them. Power plants transform chemical (nuclear) energy to thermal and then to electrical. It is a natural (physics) property of transformation heat -> electricity that it has low efficiency. Look at your thermodynamics books why. So not all thermal energy is converted into electricity in the power plants. Large parts of it (50%) are radiated in the air or used for heating of houses near the power plants IF there are living areas near the power plant. But in many cases there are no such consumers near by. Here is where the new process may be used - put such devices in the existing power plants and use as much as possible of this now unused thermal energy.

    The result: power plants will produce same amount of electrical energy, but also O2 and hydro-carbonic substances, which may be used as fuel. And will use CO2 for this. If this is done efficiently, this can be a very big contribution to CO2 emission reduction in the power plants.

    Just my thoughts ...

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