MPG Increase - Non-Ethanol Gas - What to Expect?

Discussion in 'Fuel Economy' started by Mightymouse13, May 9, 2012.

  1. brick

    brick Answers to "that guy."

    I don't have a satisfying technical answer for you but this isn't the first car where I've recorded evidence of a FE hit way above that 3%. I tried the same thing in my Prius over the course of a few months while i was living in SC and the results were similar. The thing to keep in mind is that the 3% figure is based on the raw energy content of fuel. (I.e., E10 theoretically contains 3% less chemical energy than E0.) But what matters is how much mechanical energy an engine can extract from fuel. If you stack a 3% hit on chemical energy on top of another few percent due to some finicky thing like OEM ignition maps being optimized for E0 while E10 would need a couple degrees more advance to be equally efficient, 7% comes pretty quick. There's also the fact that ethanol loves water and will readily absorb it from any available source. What's to stop condensation from forming in a cool underground tank as warm surface air fills the space left as that tank empties? Even a small quantity of moisture in fuel is bound to impact combustion even if we're just talking about a tiny mass fraction. I don't think any cheating or bias is required for these results to be plausible.
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  2. phoebeisis

    phoebeisis Well-Known Member

    I get it-with the price sooo close-$1.45 vs $1.60
    not much point in reformulating
    besides that $1.45 wholesale gas- is E10 I-
    84 octane plus ethanol to boost to 87 octane'
    87 octane gasoline-no ethanol-might still have required"some other" octane booster-
    and oxygenator-which wouldn't have been free-ethanol is a cheap octane booster
    so the actual price difference-might be "not much"
    besides PURE 87 OCTANE is pretty expensive "for some reason"
    despite the drop in fuel prices-

    Brick-yeah it is a puzzle-
    I don't think modern vehicles-ignition maps- would have any problem adjusting to E10-
    Heck E10 is the NORMAL fuel they have been designed for(but aren't EPA tested with)
    The water -maybe-
    It is puzzling that soooo many competent drivers report the bigger than it should be impact-
    A mystery for now

    I got "better" than I should have gotten MPG on one tank of Pure-but my "tanks" vary too much so….
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  3. litesong

    litesong litesong

    phoebeisis likes to pretend it is smarter & can outthink many people who do report better E0 mpg than 3% more than E10. So phoebeisis changes the rules by saying "why you guys have ta be usin' E20".

    All phoebeisis has to know is high 114 octane, high compression ratio(16:1) ethanol engines were designed to burn & get the maximum efficiency from high 114 octane ethanol. High 114 octane ethanol, as used in low 87 octane, low compression ratio(9:1 to 11:1) gasoline engines, can NOT deliver its energy efficiently. Coupled with its lower btus per gallon, ethanol delivers 3% less mpg due to its lack of energy, PLUS ethanol delivers 3% to 5% less mpg, due to its lack of an ethanol engine. Yes indeed! My last five low 87 octane, low compression ratio gasoline engines, show that E10 loses 8%, 8%, 7-8%, 7% & 5% mpg, compared to E0.

    The rules are simple:
    Ethanol engineers know how to design ethanol engines to get the most efficiency from 100% ethanol.
    Diesel engineers know how to design diesel engines to get the most efficiency from 100% diesel.
    Gasoline engineers know how to design gasoline engines to get the most efficiency from 100% gasoline.

    Mixing 114 octane ethanol into 84 octane gasoline can NOT deliver maximum ethanol efficiency when used (not burned efficiently) in 87 octane gasoline engines. On top of that, the 84 octane gasoline molecules aren't delivering their most efficient best either, in 87 octane gasoline engines.
    Last edited: Nov 21, 2015
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  4. litesong

    litesong litesong

    The only reason 87 octane E0 is expensive compared to 87 octane E10 is that the EPA & "ethanol in gasoline industry" has driven E0 to rarity, which automatically raises the price of rare items. If E0 was available in 300,000 gas stations around the U.S. & Canada, E0 would be nearly the same as E10 in price. Once people discovered their vehicles were traveling 8% to 5% further with each tank, E10 would soon become the rare fuel. As it is, grassroots now lists 10,306 E0 sources in the U.S. & Canada, which is about 3-4 times more than the government supported 2500-3000+ E85 sources.
    Last edited: Jan 28, 2023
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  5. phoebeisis

    phoebeisis Well-Known Member

    Yeah makes sense
    Pure is the only PURE gasoline station near me
    and it is much more expensive than 10% gas
    despite ethanol and "gasoline" being pretty close in price

    The rest-your top post-
    I'm just asking WHY
    because the EPA flat says you should lose just 3%
    but LOTS of folks say otherwise
    Heck my own results-are about 5% on the suburban

    So not claiming to be smarter-but doubt the EPA is lying
    and current engines are designed to use 10% and higher ethanol
    These engines ARE 10% ethanol engines-heck most can handle 15%-no problem

    My guess-still-is perhaps the 10% isn't 10%
    and I think someone earlier suggested that perhaps the 10% ethanol
    has a bit more water in it than we realize-
    water we paid for at the pump-
    of course water will condense-and mix-with the ethanol
    but forum members never trust the onboard NAV MPG
    They all go old school-and actually measure several tanks-
    actual calculate the mpg
    miles traveled/ gas pumped in

    I really don't know why so many folks-myself included-get poorer mpg-
    PART THROTTLE FE than we should
    Your suggestion-
    that the engineers are not designing these engines(and the programing-spark timing advance etc) with 10% ethanol in mind
    I have my doubts
    now perhaps OUR-FORUM MEMBERS-drive in such a way-meaning we turn the engines off-or drive with a closed throttle plate-cooling engine "too much"
    maybe there is something to that
    if that is what you are suggesting

    But pretty sure folks who "drive normally" also report a greater than 3% drop in FE with 10% ethanol

    I'm always suspicious-when gasoline was pricy there was some point in putting 15% ethanol in and saying it was 10%-cheating to make $$
    But now-no point in doing that since gasoline and ethanol-too close in price(guessing too close in price)

    Bottom line-I don't know why so many report the poor 10% results-
    but a profit motive-cheating stealing-always tops my list-
    water in poorly maintained underground tanks
    or greater than 10% ethanol
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  6. JonNC

    JonNC Driving Smarter Since 06/07/2011

    phoebeisis, what makes you think that just because a .gov agency says something that it's the truth?
    You ask, why would the EPA lie?
    I ask, what incentive do they have to tell the truth?

    Let's use some easy numbers pulled from the ether:

    Say the average person gets 300 miles per 15 gallon fill, for 20 mpg.
    300 miles x 8% = 24 extra miles per tank.
    324 miles on 15 gal of E0 / 24 (the extra miles) = 13.5 tanks

    So, it would take the average person 13.5 tanks to earn what would basically be one free tank when counting overall miles compared to running E10.

    If it (E0) were to be marketed in a way to demonstrate that people could go 8% further for the same amount of fuel, would it really be all that attractive to your average consumer?
    The payoff isn't immediate, therefore most would gladly pay less now for diluted fuel.

    I'm currently paying $0.30 more for E0 87 than the E10.
    E10 87 needs to be $3.75 per gallon just for me to break even.

    But, in a free market, I have no other way to voice my displeasure in having the gas I'm buying diluted with garbage, other than to NOT BUY IT and willingly pay more for pure gas.

    And I make that choice with a smile on my face everytime.
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  7. phoebeisis

    phoebeisis Well-Known Member

    Pretty sure I didn't say the EPA was
    "telling the truth in respect to 10% ethanol"
    And " the truth"
    isn't the same as "being right"
    Now I was pretty clear-I got about 5% better with Pure than with shell 87 octane
    This is with the 98 suburban-haven't measured the 2006 prius

    But I don't think the EPA is intentionally LYING- no way-
    If the EPA had tested 10% and got numbers much less than 97% of PURE gasoline FE
    and suppressed -didn't release those results
    Guessing the EPA OUTSOURCED any 10% testing-but still no point in lying(except for corn states)

    (and PURE GASOLINE usually has to be oxygenated in most places-so it has less energy than a pure long hydrocarbon-and it needs an anti-knock ADDITIVE- actual OCTANE- the molecule-is pricier than "plain mixed gasoline"

    So despite my being more than average suspicious-paranoid-
    There is ZERO CHANCE the EPA is lying about their results in testing 10% ethanol

    Which is why I'm so puzzled by some many reliable results-reported by reliable folks here-
    that don't agree with the 97%

    Perhaps someone should back to back test Pure vs 97%
    in the same way they do the 60 mph FE test-
    actual on the hy test?

    Now my 98 suburban is only "rated" to take 10%
    not the 15% that was being pushed when oil was pricier
    so I suspect my suburban is "barely- built to a price-meaning just barely-CHEAP!" able to withstand the ill effects-seals and various metals-and the water-of 10% ethanol"

    My main 10% ethanol concerns are
    1) it is using farm land AND WATER- perhaps some from deep aquifers that will never be replenished-to produce fuel-fuel that barely makes $ and cents sense
    and CO2 sense-BARELY
    2)might be bad for my older vehicle-which I intend to repair until it turns to dust

    The slightly poorer than predicted FE- not a huge concern
    Just an INTERESTING result

    I do wonder WHY many folks don't get the predicted 97%

    I haven't seen a good answer yet
    and unintentional bias is still on my list
    Perhaps we-you- are driving a bit differently when using PURE vs 10%-
    bias always a good bet
    it is the WHY of double blind testing

    And I do wonder if our driving style-with engines that could be cooler than average-hurts FE- maybe more with 10% that with PURE(especially if the 10% has a bit of H2O in it)

    I just haven't seen a plausible reason for the poorer than predicted FE-but I do wonder about our hypermiling style-it might favor less ethanol gas-and we really don't need much octane boost-part throttle driving etc

    I'm puzzled-no good answer
    Last edited: Nov 22, 2015
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  8. krousdb

    krousdb Defiant NX-74205

    Do you have additional E0 tanks to report? What type vehicle are you driving now?
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  9. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi All:

    Weighing in here because I did some of the E10 vs. non-E10 a few years ago in the Accord and it was 2 to 3 percent. I have read tens of reports of 5 to 10 percent among members here for years but it was not my experience. Especially the Ford Escape Hybrid drivers.

    I have a big drive coming up in June - TBA - and it will be completed with E0 from coast to coast but it is not an easy task finding this stuff. The Ethanol free site is way behind what is available and I do have to concern myself with cost as a cross country journey for < $75 is doable if fuel costs including the non-Ethanol laced stuff is not a much over $0.20/gal more. A lot of metrics to be considered for a drive beyond just the maximum whereas it all surrounds around the maximum.

    In any case, if you have E0 near you, buy it.

    Following the theme, if the long term fuel trims realign after a switch to E0, does it take just one tank for a modern fuel injection system to learn it is running E0?

    litesong, 08EscapeHybrid and krousdb like this.
  10. krousdb

    krousdb Defiant NX-74205

    Another question along those lines. How are the fuel trims set at the factory? Are they optimized to E0 or E10? I have read that the EPA testing is performed with E0 so my guess would be that the initial trim would be set for E0. I assume that my Two Eco came with a full tank of E10. So while I am burning through those first 900 miles or so, it will be learning E10. And the next fill, which will be E0, it will need to unlearn what it just learned. Would there be any value in adding E0 now at the half full mark, effectively giving me E5?
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  11. krousdb

    krousdb Defiant NX-74205

    Filled up today with 92 Octane E0 for $2.219. 87 Octane E10 at the same station was $1.719. The trip back home was pretty good considering the temperature. IMG_0103.JPG
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  12. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    I'd welcome that 55 deg F right now. Still , I couldn't get that excellent trip result. And I'm not carrying a big bag of Dog Chow on the hood.
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  13. krousdb

    krousdb Defiant NX-74205

    Actually, the dog chow is an optical illusion. It is on a the top of a cabinet that is in front of the car. By the way, the Eco score of 75 was really depressing. Just think what result I would get with a 96 or so.
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  14. krousdb

    krousdb Defiant NX-74205

    I saw your comment on Can you elaborate?
    "Any chance of adding stations that sell ethanol free diesel? – Martha Clark, Canterbury, NH (January 10, 2016)....There are many reasons NOT to have ethanol in gasoline(E0) & diesel. ONE reason NOT to have 10% ethanol in gasoline(E10), does NOT apply to ethanol in diesel. Ethanol is octane 114, whereas 87 octane gasoline is, of course, 87 octane. Since the wide differences in octane, only adding 10% ethanol to 87 octane gasoline(E0), ethanol CAN'T burn & give up its energy efficiently in 87 octane, low compression ratio (9:1 to 11:1) gasoline engines, so there is a 5% to 8% difference in mpg between E0 & E10. Diesel is ~ 118 octane(more?). So the octane difference is very little. Do others here, know if bio-diesel delivers less mpg than undiluted diesel? – litesong, Everett, WA (January 10, 2016)"
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  15. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    Yeah , I figured it was an illusion, but I couldn't resist. And I wonder how the heck they figure that Eco score , anyhow. I don't think my Gen 3 Liftback has it. Maybe just the Gen 4 and the c.
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  16. 08EscapeHybrid

    08EscapeHybrid Moderator

    In my FEH it generally takes 2-3 tanks to get back to my full E0 capability.
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  17. brick

    brick Answers to "that guy."

    Wait...diesel? They put ethanol in diesel?
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  18. EdwinTheMagnificent

    EdwinTheMagnificent Legend In His Mind

    I was wondering about that as well. And isn't diesel rated by cetane , not octane ?
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  19. 08EscapeHybrid

    08EscapeHybrid Moderator

    I don't think ethanol is added to diesel. It would thin it out, and would lead to injector problems.
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  20. litesong

    litesong litesong

    More updates for this old thread: now lists almost 14,000 E0 sources in the U.S. & Canada. Iowa, which produces 25%-30% of america's corn crops for ethanol production, now has 322+ sources of E0, more than E85 sources. Compared to the grass-roots developed & listed 14,000 E0 sources, E85 sources, pushed by the "ethanol in gasoline industry" & the EPA are listed only as 4000, which may be a stretch. The "ethanol in gasoline industry" lies often & long, but are entirely too obvious.
    My decades-long personal comparison between E0 & E10, continues fairly stable MPG percentage differences between the two. Five low-compression ratio, 87 octane designed gasoline engines show that E0 provides 8%, 8%, 7%-8%, 7%, & 5% higher MPG than E10.
    Often E0 deniers say E0 is too costly per gallon compared to E10. However, availability of E0 does NOT align itself to state "income per capita" in the U.S. Wisconsin, below the states average "income per capita" in the U.S., has the most availability of E0, at 949 sources. Also, the cheapest 87 octane E0 availability is low in the state, overwhelmed dramatically by much more expensive high octane E0. North Carolina, 12th from the bottom of state "income per capita", has the second greatest number of E0 sources(878), available. Florida, much below average state "income per capita", has the third highest E0 availability(865). New York City has almost no E0 sources. But, New York state has ~ 770 E0 sources (most in more expensive higher octanes), all(?) concentrated in much poorer per capita counties, away from New York City. Mississippi, dead last in state "income per capita", Arkansas, 3rd from last, & Alabama, 5th from last, have goodly numbers of E0 sources, available. Georgia, well below average income per capita has over 600 E0 sources.
    Last edited: Feb 22, 2019
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