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Transportation Power Science

More "Miles Per Acre" From Bioelectricity Than Ethanol 223

CarnegieScience writes "Scientist calculate that, compared to ethanol used for internal combustion engines, bioelectricity used for battery-powered vehicles would deliver an average of 80% more miles of transportation per acre of crops, while also providing double the greenhouse gas offsets to mitigate climate change."
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More "Miles Per Acre" From Bioelectricity Than Ethanol

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  • by LordKazan ( 558383 ) on Thursday May 07, 2009 @03:17PM (#27864987) Homepage Journal

    Food crops as energy sources was never a good idea, we didn't breed them for their modern harvestable energy content, and even if we did we'd be offsetting fuel crops. Algal Oil is a MUCH better biofuel solution as it can be build anywhere you have the following things:

    A) Land [cheaper the better]
    B) Source of Water [doesn't neccesarily need to be fresh or particularly clean, in fact fertilizer polluted water might even be a good thing]
    C) Source of Carbon Dioxide [clean CO2 .. so cannot pull it straight from the air, have to filter it.. but pretty much everywhere]
    D) Sunlight

    And it already works, we have "pilot plants" already cranking it out.

    Don't have to offset prime forest or prime agricultural - vast stretches of the semidesert southwest would be usuable.

  • Graphic (Score:1, Informative)

    by Anonymous Coward on Thursday May 07, 2009 @03:22PM (#27865065)

    http://www.ciw.edu/sites/www.ciw.edu/files/images/PRFieldCampbellBioenergyTransport-REVISEDGRAPHIC5-4-09.jpg

  • by evanbd ( 210358 ) on Thursday May 07, 2009 @03:59PM (#27865731)
    They also compare cellulosic ethanol and other non-corn options. Ars Technica [arstechnica.com] has a better writeup.
  • Re:Oy. (Score:4, Informative)

    by evanbd ( 210358 ) on Thursday May 07, 2009 @04:02PM (#27865793)
    They did take those things into account. That's why the study is interesting. It includes the conversion efficiencies of both the combustion engine and the power plant, the transmission losses of both the fuel and electricity (trucking the fuel around doesn't cost much fuel, but it's not zero either), and the lifecycle energy cost of the batteries. I'm not expert enough to say the authors did a completely correct job, but they certainly did a very thorough job.
  • by Rei ( 128717 ) on Thursday May 07, 2009 @04:45PM (#27866687) Homepage

    Whether or not EEStor is real or not is becoming increasingly unimportant. When they first started pushing their (questionable) tech, conventional li-ion cells on the market were 160Wh/kg and most of of the stable ones were ~$1/Wh and under 100Wh/kg. Now conventional li-ion cells are 200Wh/kg with longer life, the stable ones are under $0.50/Wh and rapidly headed toward $0.35/Wh or so, and there have been literally dozens of lab breakthroughs that if any one of each anode and cathode tech were commercialized, would make li-ion cells have the claimed energy density of EEstor's EESU. So, honestly, I don't really care all that much about whether they're legit or not anymore.

    Hydrogen is already obsolete. I mean, come on, 6 figures for a fuel cell stack strong enough to run a car? 1/3rd the efficiency of EVs, and that's *if* you use fuel cells rather than combustion? 5 year fuel cell lifespans, tops? Many more moving parts (including a compressor)? An explosive, ozone-depleting fuel that leaks through almost anything, pools under overhangs, has a ridiculously low ignition energy, burns in almost any mixture with air, rapidly undergoes deflagration to detonation transitions, etc? That has no better range than a modern li-ion EV? And takes 3 times as long to fill as the high end rapid-charging EVs and 1.5 to 2x as long as the low-end rapid charging EVs? Why exactly is this supposed to be appealing?

  • Re:Units? (Score:3, Informative)

    by Nick Ives ( 317 ) on Thursday May 07, 2009 @04:51PM (#27866781)

    I thought they were the Nationalsozialistische Deutsche Arbeiterpartei or NSADAP...!

  • Re:Units? (Score:5, Informative)

    by AliasMarlowe ( 1042386 ) on Thursday May 07, 2009 @04:57PM (#27866903) Journal

    Miles per acre? What's that in rods per hogsheads?

    Miles per acre ca't be converted into rods per hogshead. However, you may find the following conversions useful:
    1 mile per acre is exactly 80 rods per rood.
    1 mile per gallon (US) is exactly 63 furlongs per firkin (US)
    Anything else you need can be computed from information at http://www.unc.edu/~rowlett/units/index.html [unc.edu]

  • by joib ( 70841 ) on Thursday May 07, 2009 @05:42PM (#27867673)

    Algae might be a better biofuel compared to the alternatives in many ways on paper at least, but it's far from actually proven to work economically. E.g. the principal investigator of the $100 million NREL aquatic species research program has the following to say: http://www.theoildrum.com/node/2541 [theoildrum.com]

  • by lupine ( 100665 ) * on Thursday May 07, 2009 @06:28PM (#27868529) Journal

    You were very generous with 40mpg. The highest mileage a 2009 car gets on E85 is only a paltry 16 city 23 hwy, much lower than the 22 city 32 hwy on gasoline. Most new vehicles that burn E85 are trucks so the cafe average is probably closer to 13mpg, which would be worse if running on E100.
    http://www.fueleconomy.gov/feg/byfueltype.htm [fueleconomy.gov]

    plants are only about 6% efficient(max) at converting sunlight into sugars & cellulose. Modern solar panels are around 20% efficient(very expensive space panels are at 40%).

    ethonol must be distributed by truck or rail(there is no pipeline yet).
    electricity transmission loss is around 3%.

    How you use the energy matters also. Internal combustion engines waste most of the energy as heat(75-80%) and use only 20-25% of the energy to move the car. Electric batteries and motors are around 85% efficient.

    Electricity wins.
    Now if we can just get some affordable batteries and solar panels...

  • by Rei ( 128717 ) on Thursday May 07, 2009 @07:48PM (#27869969) Homepage

    Oh come on, not this lithium scarcity nonsense [google.com] again....

"Everything should be made as simple as possible, but not simpler." -- Albert Einstein

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