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  1. Standard member sonhouse
    Fast and Curious
    25 May '08 10:44
    http://www.sciencedaily.com/releases/2008/05/080519092205.htm

    This is the kind of thing I envisioned that may deal with CO2 coming off vehicles. I understand you make about three times the weight in CO2 as the weight of the original fuel, like gasoline and this is a significant new technology that can perhaps deal with it and keep it out of the atmosphere.
  2. Standard member PBE6
    Bananarama
    27 May '08 18:43
    Originally posted by sonhouse
    http://www.sciencedaily.com/releases/2008/05/080519092205.htm

    This is the kind of thing I envisioned that may deal with CO2 coming off vehicles. I understand you make about three times the weight in CO2 as the weight of the original fuel, like gasoline and this is a significant new technology that can perhaps deal with it and keep it out of the atmosphere.
    The back-pressure created by the carbon filter would cause a serious drop in power generation and engine efficiency. Considering that the maximum achievable efficiency for a car is already in the neighbourhood of 30%, this might not work so well on a tailpipe.
  3. Standard member sonhouse
    Fast and Curious
    28 May '08 09:02
    Originally posted by PBE6
    The back-pressure created by the carbon filter would cause a serious drop in power generation and engine efficiency. Considering that the maximum achievable efficiency for a car is already in the neighbourhood of 30%, this might not work so well on a tailpipe.
    What about fuel cells? Aren't they a lot more efficient? Couldn't this capture technology be used more effectively on them? Even for combustion engines, there might be mechanical tricks to use, like the blower that uses exhaust gas to compress air and fuel into the engine, something like that might be used to power a pump to increase the flow in the CO2 device.
  4. 28 May '08 10:34 / 1 edit
    Originally posted by sonhouse
    This is the kind of thing I envisioned that may deal with CO2 coming off vehicles.
    Not going to happen. It is more sensible to find a better fuel than try to clean up the one we have. Alternatively just use what we have more efficiently (diesel, hybrids etc).

    I understand you make about three times the weight in CO2 as the weight of the original fuel,
    Fuel is so great for cars largely because of its energy/weight ratio and its ease and speed of handling. If we have to capture the CO2 the weight would be a problem as would the size of the capturing device (larger than your fuel tank) and the time required to clean it out every time you get a refill.

    A good fuel cell uses clean fuel (like hydrogen for example) and only produces water (no CO2).
    We can also burn hydrogen instead of petrol/diesel in a combustion engine but hydrogen is harder to store than petrol. I think that a fuel cell is more efficient (and possibly lighter) which is why it is preferable to combustion when it comes to hydrogen as the fuel.

    http://en.wikipedia.org/wiki/Hydrogen_vehicle
    has some more information including showing that even with the more efficient fuel cell, if you are making your hydrogen from electricity then an all electric car is over twice as efficient as a fuel cell vehicle.
  5. Standard member sonhouse
    Fast and Curious
    28 May '08 10:45
    Originally posted by twhitehead
    Not going to happen. It is more sensible to find a better fuel than try to clean up the one we have. Alternatively just use what we have more efficiently (diesel, hybrids etc).

    [b]I understand you make about three times the weight in CO2 as the weight of the original fuel,

    Fuel is so great for cars largely because of its energy/weight ratio and it ...[text shortened]... gen from electricity then an all electric car is over twice as efficient as a fuel cell vehicle.[/b]
    I know all about that but the problem is infrastructure. We already have an infrastructure of gas stations so to use H2 would require the same for hydrogen, that would be incredibly expensive and how would you build such a network without using diesel or gas? Cats, dredgers, backhoes, all are diesel so you would be using your dreaded technology to build the new.
  6. 02 Jun '08 14:25
    Originally posted by sonhouse
    I know all about that but the problem is infrastructure. We already have an infrastructure of gas stations so to use H2 would require the same for hydrogen, that would be incredibly expensive and how would you build such a network without using diesel or gas? Cats, dredgers, backhoes, all are diesel so you would be using your dreaded technology to build the new.
    I'm betting that hybrids and electrical vehicles will beat out hydrogen. But it is partly up to the politics of the US as the govt is pushing for hydrogen.

    Of course that may change. Maybe in 10 years we will have perfected the fuel cell and hydrogen will be more desirable. But for now hybrid and full electric have so many advantages that I see them being the winner.

    I dont think diesel engines are, 'dreaded technology'. I think they still have a place for a long time to come including in the construction industry.