Op-Ed Counterpoint to ‘Analysis: Gas mileage going down?’

OPINION EDITORIAL – Bill Gephardt, like hundreds of others I’ve read similar articles about, is reporting much higher mileage losses from ethanol mixed gasoline than the 2-3 percent claimed by the EPA, in fact many say they’re getting more than a 10 percent loss. If we’re adding 10 percent ethanol to gasoline and experiencing a 10 percent loss in mileage, ethanol use is a totally wasted effort.

See Gephardt’s opinion, “Gas mileage going down?

Internal combustion engines using gasoline get up to 37 percent fuel efficiency; meaning 63 percent percent of gasoline’s energy potential is wasted. Most engines are typically only able to make efficient use of 20 percent of gasoline’s energy potential. In most engines, if you could get 100 percent energy efficiency from gasoline, you would get around 5 times more mileage than you get right now.

The first thing to understand about ethanol is that oil and water don’t mix. Ethanol is water based while gasoline is made from oil. The kind of ethanol added to gasoline is anhydrous, meaning no water. If there were water in it, the ethanol will not mix with gasoline. Then even after it’s mixed, if the ethanol comes in contact with water, it will attach to it and sink to the bottom of the tank, like vinegar in an oil and vinegar salad dressing.

Ethanol 113 Octane

Ethanol has an octane rating of 113. Although high-octane fuels cost more at filling stations, they have lower energy contents. This is because the higher an energy content a fuel has, the easier it ignites. The easiest way to explain why we look at a fuel with less energy content as being higher grade is to look at gunpowder. If you ignite simple gunpowder in the open air, it will flare easily, followed by a cloud of visible smoke. If you however encase it in tightly wrapped paper, like a firecracker, when it’s ignited, it explodes.

In an engine, the closer a piston is to the top of the piston chamber where there is the smallest amount of air space when the spark plug ignites the fuel, the more power is created. The less energy content of a fuel, the longer it will wait for the spark plug to ignite it. Most vehicles have low compression engines and use regular gasoline, which has an 87 octane rating. If you use low octane fuel in a high compression engine, it will ignite before the spark plug tells it to.

When an ignition system’s computer analyzes a gasoline/ethanol mix to decide when to tell the spark plug to ignite, it gets confused because it can’t tell the engine to produce an ideal combustion platform for igniting two different octane fuels at once. So it settles for the best results that it can.

Regular gasoline is 87 octanes, midgrade is 89, and high test is between 91 and 92 octane. That’s a difference of only a few points between them. But there’s a big difference in the engines designed to use them. Then they add 113-octane ethanol to these much lower grade fuels, a tragic leap of 16 points from 87-octane. It’s claimed this is all taken into consideration so as to produce an end product equals the right octane blend for your car. But that explanation is lost on the fact that ethanol and gasoline don’t blend when splashed mixed at fuel depots but rather remain two separate fuels.

In Conclusion

Try looking at it from another perspective. Ethanol “mixed” gasoline causes mileage problems for us that Netherlands has overcome by blending ethanol in a refining process that combines the two fuels into one homogenous product. We know we don’t experience mileage losses if we don’t add ethanol to gasoline in the first place, which is something even ethanol’s supporters don’t argue against. They however claim the mileage loss is negligible while ignoring facts showing how significant it actually is. Then there’s the lack of mileage loss when pure ethanol is used, meaning how can the lower energy content of ethanol be the cause of a mileage loss if it can be used by itself with no mileage loss.

Submitted by:  Aaron Kelly

email (with permission) op-ed writer, Aaron Kelly: [email protected]

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  • Jeff May 4, 2012 at 11:54 am

    A mix of ethanol and gas can absorb quite a bit of water before separating and still operate very well in engines without causing any harm.
    Modern cars also have flex fuel composition sensors that have no problem dealing with any mix of gasoline and ethanol.
    Even without the flex fuel sensors, most cars can handle any mix using feedback from the O2 sensors

  • Aaron Kelly May 4, 2012 at 5:50 pm

    Jeff, I agree, engines can handle E10, meaning it won’t destroy the engine, not fast enough to be able to blame it on E10 anyway, that is as long as you keep up with oil changes because ethanol makes engines run much hotter so there is more condensation build up in its oil, meaning water builds up in the engines oil much faster than usually,, and ethanol also slips by the piston rings to mix with the oil. Let look at it this way, engines are built after 1990 are built withstand the damage that otherwise might be caused by E10, and that is to use it as an oxygenate, it was never meant to be a fuel substitute because it is not designed to produce power, it is designed to produce high emissions of acetaldehyde and formaldehyde (VOC’s) that blend with nitrogen oxide smog and dissolve it,, from another paper I wrote –

    In 2005, after congress passed energy legislation that lead to MTBE being replaced with ethanol, the state of California took the EPA to court and proved oxygenates actually worsen air quality. Although oxygenates got rid of coal and diesel caused smog by dissolving it, the resulting ozone, although less visible, is more dangerous to human health and the environment. Just as California was winning the long held debate over oxygenate use, George Bush stepped in and said ethanol requirements were no longer about air quality, it’s about energy independence, meaning ethanol was being required as a fuel source, not an oxygenate.

    Brazil’s use of ethanol was pointed to as the precedent for ethanol being a solution to fossil fuel imports. What somehow seemed to escape the debate was the fact that Brazil’s success with ethanol was largely based in their car fleets converting to flex fuel engines that would burn pure gasoline or pure hydrous ethanol. We blend anhydrous ethanol with gasoline as an oxygenate designed to cause a mileage loss of in order to achieve high emissions of VOC’s. VOC’s blend with nitrogen oxide smog to dissolve it into ozone. Oxygenates are not fuels because they cause a greater mileage loss than the amount added to gasoline. At the time they were first required, mileage wasn’t a concern, smog was.

    Once ethanol got a foothold riding the coattails of the federal subsides that supported it, getting rid of it or changing to hydrous ethanol has become increasingly difficult. This is in spite of that fact that ever since it’s use began in the spring of 2006, the value of the dollar has been slipping. This of course drives up the cost of US imports, including oil, in fact since oil is traded in dollars around the world, the price has gone up globally. This is because, and it doesn’t take a rocket scientists to figure this out, in fact George Bush argued in 2005 when supporting MTBE over ethanol, that switching to ethanol would drive up the price of gasoline, it would have to in order for ethanol to compete with it because gasoline was still very cheap back then.

    • larry Jonson May 5, 2012 at 6:00 am

      Mr. Kelly

      Wjere do you get the ideas to make such outlandish and inaccurate statements? Not only are you way off base with the fuel chemistry issues but your perception of the political issues relating to oxygenates in California is also fiction. MTBE was phased out due to liability concerns, not because of 2005 legislation.

  • Aaron Kelly May 8, 2012 at 5:23 pm

    Larry, I apologize it took so long to answer your question. What you might not understand, or simply disagree with the way I explained it, was that the oil companies and MTBE industry fought very hard from April of 2002 all the way up to the passing of the Energy Act of 2005 to get congress to give them a liability waiver from defective product lawsuits so they could continue to use MTBE. When they didn’t get it, they began to phase out it’s use replacing it with ethanol by the spring of 2006.

    As far as your concerns about fuel chemistry, if you were more specific in your query, I would be happy to answer your question. I assure you that my facts are correct and would be happy to provide sources for anything you require. I admit to linking the facts together in order to provide the content for this “opinion” piece. I further qualify my opinion in the end pointing out that ethanol blended with gasoline at a refinery (rather than splash mixed) does not cause a mileage loss, ethanol by itself does not cause a mileage loss, and of course gasoline by itself does not cause a mileage loss. It’s only when gasoline and ethanol are splash mixed the way we do it that we get an admitted 2-3% mpg loss.

    I further pointed out that many Americans, including myself and the author of the original “opinion” piece “Gas mileage going down”, report greater than 10% mileage losses. Since it’s not possible for the argument that ethanol causes a slight mileage loss due to its lesser energy content than gasoline because ethanol by itself or blended at the refinery with gasoline causes no mileage loss, and since these are not obscure enough facts for the experts who report the energy content aspect of ethanol being a factor to miss, it appears they are either lying or misinformed, both of which are unacceptable. My personal opinion is they are lying, in fact I can prove it. But that is a whole other article.

    Thank you for your interest, I hope that answers your question.


  • Cobalt June 9, 2012 at 1:43 pm

    This article’s argument is invalid. Ethanol was added to replace MTBE, a horribly carcinogenic additive for gasoline which prevents knock. Without either ethanol or MTBE, your gasoline would destroy your engine. Your understanding of fuel ignition is incomplete. Energy content has nothing to do with how fast or slow the fuel burns, that’s the octane rating.

    Energy content (measured in BTUs) also has nothing to do with how much work can be generated from a fuel. BTUs are a measurement of heating value. A car which has been optimized for ‘wet’ ethanol (ethanol with some water) will get better fuel economy than a gasoline vehicle because of its higher combustion efficiency.

  • Laboratory Scientist July 25, 2012 at 8:07 am

    “But that explanation is lost on the fact that ethanol and gasoline don’t blend when splashed mixed at fuel depots but rather remain two separate fuels.”

    I have no problem with people who dislike ethanol for whatever their reason, as long as it it fact based. This artilce is obviously written by someone who has spent 0 time in a lab in their life, but probably claims they did well in high school chemistry, maybe… Not even the American Petroleum Institute will tell you that these two fuels don’t blend and remain seperate. The API is the biggest anti-ethanol group out there, and even they cannot stretch the facts like that. Ethanol and gasoline are both miscible fluids. With time (a lot of it) they will eventually seperate. Just like your captain and coke will eventually seperate. I don’t know about you but neither the gas in my car or the captian and coke last long enough for either to happen. Please, come to my lab and I will do an amazing test (pouring the two together) and show you that you should never listen to a journalist just because they wrote an article. Great piece of work. I bet you win a Pullitzer for it, or at least your mom will say you did a good job.

  • Marc Rauch July 28, 2012 at 1:54 pm

    Aaron –

    The mistake that has been made here, in both the original article written by Bill Gephardt and in your reply to it, is that you are referring to “energy content” as being the reason why a gasoline-powered spark induced internal combustion engine gets less mileage with ethanol (or an ethanol-gasoline blend). And this is an error that has been made for many years, and is repeated, and repeated, and repeated.

    It’s not a matter of “energy content,” it is a matter of “engine optimization.” A spark induced ICE that is optimized to run on ethanol (or a high ethanol-gasoline blend) will deliver mileage that equals or even exceeds the mileage of gasoline in a gasoline optimized ICE. While you do touch upon the importance of spark timing to properly ignite either fuel, spark timing is just one of three factors that must be addressed in comparing mileage efficiency in the two fuels: the other two factors are length of piston stroke (ethanol permits longer strokes per same time intervals), and proper fuel injectors. The fuel injectors in the typical gasoline-powered engine (non-flex fuel and flex fuel vehicles) actually wastes ethanol. This is the probably the single biggest reason of the three why there is comparative mileage loss.

    To illustrate this another way, if you had an ethanol optimized engine (which correctly addressed all 3 issues) and you tried to use straight gasoline, the engine might not even run, but it would surely produce fewer miles per gallon of fuel. However, it would still be correct to say that gasoline has a greater energy content than ethanol (according to BTU style measurements). But as you can see, the higher energy content is irrelevant.

    This has been known to automotive engineers and scientists for more than 100 years. Unfortunately, it has been successfully swept under the rug by the petroleum oil industry.

    On a slightly different note, I find that the issue of water in ethanol causing a problem with gasoline-blends is also a canard. I say this because water separation – if it occurs – does not happen overnight, or after just one week or one month’s inactivity. It takes a longer time. So while this issue has been used to frighten consumers, it is no more significant than the problem of letting an engine with gasoline sit idle for an extended period of time. As I’m sure you know, if you store a vehicle or lawn mower type device for an extended period you are supposed to do one of two things to insure that you don’t catastrophically damage the engine: you either drain the fuel, or you add something like Sta-Bil to the fuel. You would do the same thing with an ethanol-powered engine. It’s funny how the “bad-gasoline” problem gets ignored when anti-ethanol people try and scare people away from trying ethanol or a high ethanol-gasoline blend.

    Incidentally, I own a 2002 non-flex fuel Ford Taurus and I run it on either straight E85 or high ethanol-gasoline blends – far in excess of E10 or E15. The vehicle’s engine has not been converted in any manner, and I have not done anything to adjust the engine’s computer. Yes, the check-engine light is illuminated, but I know why and so I am not concerned. I purchased the vehicle used for the purpose of experimenting with it. It passes California smog tests and I do not have any liquid leaking from its hoses or connection points. But, I do save money every time I fill the vehicle. The small mileage loss I do experience is compensated by the lower E85 price.

    Thanks for your time.

    Marc J. Rauch
    Exec. Vice President/Co-Publisher

  • Tim December 29, 2013 at 1:34 pm

    This stream has been dead for awhile, but we just got 87 with 10%ethanol in Omaha and so it’s become relevant. We have had 89 with 10% ethanol since before I moved here in 2009, but the 87 is new. So I will be describing my experience with the two.

    Before beginning, let me say I’m quite surprised at the previous comments, especially the belligerence of “laboratory scientist”. This is not my area of expertise in the least, but I am a federally funded Ph.D neuroscientist and that’s not the way to educate or debunk a lay persons perspective. Furthermore, I am baffled at the disregard for the main focus of the article which is gas mileage decreasing with the addition of ethanol. Regardless if Mr. Kelly reported the correct description of the mechanisms concerning how the fuels mix or ignite, the fact remains that a significant number of people have reported a decrease of >10% in mileage per gallon. The only one who speaks to this is Marc Rauch and this is with a personal case report or n = 1. Makes one wonder why all of these “experts” have not cited any scientific studies with large numbers of diverse vehicle models tested. In the pharmaceutical industry, when a drug comes to market a certain number of side effects will have been identified in the clinical trials. However, this does not mean that these are the only ones or even that the prevalence is correct. It’s only when the number of people taking the drug has increased tremendously do we see any unknowns that begin to be reported as individual case reports or anecdotes. Once this reaches a critical mass the FDA steps in and orders a reassessment of the drug. It seems that the same thing is happening here. Originally, ethanol additives were thought to have negligible effects on mpg, but with mass consumption we are seeing more and more reports of significant decreases in mpg. At some point, the validity of this case reports will need to be examined and new, better designed studies performed.

    In the mean time, here’s my case report on two cars (n=2). We have a 2005 elantra and 2006 outback. We used to live in Phoenix with regular 87 gas. We moved to Omaha in 2009 and started filling up with 89/E10 because it was cheaper than regular 87. We saw no difference in mpg. Recently, Omaha changed over to 87/E10 which was even cheaper. We are on our second tank with both of these and we have noticed a significant decrease (>10%) in mpg with both. I’ll just give the stats on the elantra for example. Previously, we averaged 30mpg for mixed highway/city driving and 26.7mpg for just city driving. Now, 26mpg and 19mpg, respectively. Now, Marc Rauch claimed that the money would average out. Close, but no. Right now 87/E10 is $3.09 and 89/E10 is $3.39. For mixed driving it costs us $0.006/mile more and for city driving it costs $0.036/mile more. Over one year of driving 10,000 miles this would cost an extra $60 or $360, respectively. Not too much for an individual, but multiply this over years and it becomes significant. Now multiply it by millions of people and suddenly there’s a lot more cash potentially going to the fuel industry.
    Now, granted we only have two tanks experience, I’ll let you know if things change.

    This is happening and is the real story. Even if the theory says we shouldn’t be experiencing this much decreased mpg, many people are, and in science if the outcome doesn’t match the hypothesis than you’ve got to go back and figure out what in your theory was wrong.

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