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The ethanol deception

  1. May 24, 2007 #1

    Ivan Seeking

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    I was just watching a review of ethanol energy on CNN. They report that Consumer Reports claims that cars using ethanol see no decrease in mileage or performance.

    Now I'm not sure what Consumers Reports claimed and a source wasn't cited, but the point of the story was to consider the performance of ethanol compared to gasoline, which was left somewhat vague in the end.

    Gasoline has about 125,000 BTUs per gallon, and ethanol has about 76,000 BTUs per gallon. The last time that I checked, the conservation of energy law was still in effect.

    Sidebar: IMO, nothing that Consumer Reports claims can be believed. This is not the first time that I have run across this sort of nonsense. In fact, just about anytime that I see a report from them on something that I happen to know about, they're wrong.
     
    Last edited: May 24, 2007
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  3. May 24, 2007 #2

    JasonRox

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    If the consumer doesn't feel like it decreased in performance or mileage, who gives a ****. The consumer is happy period.

    It's not like they're saying it's scientific. It's a Consumer Report.
     
  4. May 24, 2007 #3

    Ivan Seeking

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    It is a report FOR consumers that is supposed to be based on testing. Many people rely on their information when making buying decisions. Also, people are hoping to save money by buying ethanol fuel, when in fact the decrease in mileage will likely end up costing more than the savings gained by purchasing a cheaper fuel.

    In order to replace petroleum with corn-ethanol, it would require about twice the land area of the US to grow the corn.

    Reuters, May 19th, 2007.
     
    Last edited: May 24, 2007
  5. May 24, 2007 #4

    BobG

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    I'd say they might be right depending on exactly what they said. The fuel going in may have a difference in energy content, but a lot of energy is lost between the 'in' and the 'output' - how much energy is applied to turning the tires. You have to take into account how efficient the combustion process is.

    If the engine is designed for high ethanol fuels (i.e. - the engine has a high compression ratio), ethanol's performance is supposed to be roughly equivalent to gasoline. The engine wouldn't run at all on gasoline, which would currently be a pretty big drawback.

    This wouldn't apply to flex fuel engines that can run on ethanol or gasoline. To use gasoline, the engines have to run with a lower compression ratio and you get much worse mileage with ethanol than you do with gasoline. In other words, you're right - in the same engine, it's impossible to get the same mileage out of ethanol that you do with gasoline.

    The 10% ethanol mix that can be used by all engines also gets less miles per gallon than straight gasoline (about 3% less?), but the increase in octane gives better performance in other ways - I'd say it was a push depending on the driver's priorities.
     
    Last edited: May 24, 2007
  6. May 24, 2007 #5

    Ivan Seeking

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    What is roughly equivalent, and where are these cars? I don't know of anyone driving one. Is this verifiable or more Consumers Reports information?

    I don't see how after all of years of improvements in auto engines, we could get the same energy from 76,000 BTUs, as we do 125,000 BTUs.
     
    Last edited: May 24, 2007
  7. May 24, 2007 #6
    Simply Not True

    Well before what you call "this sort of nonsense" and "deception" it might be good to do some due dilligence.

    If we go to CNN.com we can find the article We want better mileage - but power and size, too placed today on the CNN website.

    Nothing in this article indicates that Consumer Report claims anything like that.

    If we look a bit further and go to the Consumer Report website we can find several articles where Consumer Reports states that ethanol is not more fuel efficient.

    I include two articles:

    (1) Ethanol: Growing renewable fuels

    From this report:
    "Ethanol contains less energy per gallon than gasoline, so E85 gets roughly 30 percent fewer miles per tankful. Factoring in that loss, corn-based ethanol sells for about $4.09 for the energy equivalent of a gallon of gasoline, making it more expensive than gasoline at today's prices."

    (2) The ethanol myth: Consumer Reports E85 tests show that you’ll get cleaner emissions but poorer fuel economy ... if you can find it

    Your suggestion that Consumer Report is deceiving people by claiming that ethanol is not less fuel efficient is simply untrue. In fact Consumer Report is saying the contrary.
     
    Last edited: May 24, 2007
  8. May 24, 2007 #7

    Ivan Seeking

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    I just saw it on CNN. Also, I said that they didn't cite a source

    Usually what happens is that I see the report and it becomes available later for a link.

     
    Last edited: May 24, 2007
  9. May 24, 2007 #8
    Last edited: May 24, 2007
  10. May 24, 2007 #9

    Ivan Seeking

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    Perhaps... we will see later what is linked.
     
  11. May 24, 2007 #10

    Ivan Seeking

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    In any event, ethanol has a reputation that is not deserved. It is a solution to nothing and puts food into competition with energy.
     
  12. May 24, 2007 #11

    Astronuc

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    Certainly CNN is not scientific, but I believe Consumer Reports tries to be with a very limited sample, particularly when it comes to expensive items.

    One thing CR cannot do is vouch for qualit (or quality control) of any particular item. We have relied on them, but with mixed success, although the experience has been more positive than negative.
     
  13. May 24, 2007 #12

    Ivan Seeking

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    I've seen too many false claims to believe anything they say.

    I had a buddy who owned the vaccuum shop in town, and one day he showed me a CR on two Eureka vacuum cleaners. One passed with flying colors and the other failed. What Tony was so amused with is that the only difference between the two models was the paint and decals.
     
  14. May 24, 2007 #13

    Ivan Seeking

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    In fact, I'll do a little digging and see if I can find it, but, IIRC, some years ago they got caught on something like this and blamed it on outsourcing - they don't do much of their own testing.
     
  15. May 24, 2007 #14
    Talking about false claims, did you read the two links from Consumer Reports that I included? If you did you will have to admit that the statements about deceptions in this matter are simply unfounded.
     
    Last edited: May 24, 2007
  16. May 24, 2007 #15

    russ_watters

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    Without knowing the nuts and bolts of the claim, it is tough to evaluate, but thermodynamically, "miles per gallon" (and therefore btu per gallon) is a largely useless thing to compare between fuels. The reality is that if you want to use ethanol in a car, you should change-out the fuel injectors to inject more ethanol, giving you in the end almost exactly the same thermodynamic efficiency and performance, but with more per-gallon or per-lb consumption.

    Along a similar veign, most natural gas home heating furnaces can be converted to run propane and the basic difference is the orifice regulating the flow is different. Change-out the orifice and the performance is identical.

    What is more useful is probably the chemical efficiency of the fuel. It is related somewhat to energy density, but fuels with a higher ratio of carbon to hydrogen (such as ethanol) produce less energy and more CO2.
     
    Last edited: May 24, 2007
  17. May 24, 2007 #16

    brewnog

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    Energy content is pretty meaningless for performance comparisons between fuels. Ethanol is much more knock resistant than gasoline, therefore higher compression ratios can be utilised. Even on an unmodified (or gasoline) engine, ignition timing can be advanced, and charge density is increased due to the heat of evaporation of ethanol.

    I'm not saying performance on ethanol is identical to that on gasoline, but then a gasoline-optimised engine isn't identical to one designed (or modified) for ethanol.
     
    Last edited: May 24, 2007
  18. May 24, 2007 #17

    BobG

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    You don't see any 100% ethanol engines on the road. For one thing, there's no where to fuel them up. You can see 33 of them on Sunday in the Indianapolis 500.

    About the closest you might see functionally would be MIT's ethanol-boosted engine that only injects ethanol directly into the combustion chamber when extra power is needed. (http://web.mit.edu/newsoffice/2006/engine.html and http://www.psfc.mit.edu/library1/catalog/reports/2000/06ja/06ja016/06ja016_full.pdf) That's far from being on the road, either.
     
  19. May 24, 2007 #18

    Ivan Seeking

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    If you read the op, the claim of deception was applied to the use of ethanol. This was not primarily about Consumer Reports. I just happen to know from experience that CR is sometimes full of it, so the report didn't surprise me.

    I will post the story a little later as it should come up after a few hours.
     
    Last edited: May 24, 2007
  20. May 24, 2007 #19

    Ivan Seeking

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    Just for perspective, didn't I hear that the use of ethanol was not based on performance, but other motives?
     
  21. May 24, 2007 #20

    Ivan Seeking

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    Okay, I wasn't aware of the higher compression ratios possible, but since these cars are not available and the reality is what we actually have, ethanol probably offers no financial advantage.

    And for anyone who want to do the calculation, when you see the 400 gallon per acre yields for corn, after the processing requirements, multiply by 0.3 [best case for corn] as the net gain. Others claim that the real multiplier is more like 0.1 or 0.2, and some even argue that the multiplier is 0.0 - that ethanol energy is just hidden petroleum energy and it is only competitive due to subsidies.
     
    Last edited: May 24, 2007
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