MPG on Ethanol Blend E10 or E85?

All 98,000 miles of driving my current Prius have been with E10.

These graphs should satisfy your quest for data... and if not, there's many spreadsheets available too:





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John has the data and charts, I just observe about a 3 mpg hit from E10. Cleaner air, perhaps, but you burn more fuel.

 

5/07 I was getting around 48~52 consistently but now getting 41-43. I did get new tires about 1.5 months ago which I know is contributing to the decline. BTW, I live in Vancouver. I always looked forward to the summer gas but understand the benefits of the new blend.

 

i dont know why everybody is so excited about E-10. you get far worse gas mileage with it and they charge you the same price. i hope Shell never starts selling it. thats all we use. mostly because its good but we have a Shell Mastercard that gives us 5% off of a gallon of gas. we had gotten a deal on some gas cards (one of the department stores were selling them )...buy one get the second half off so we were getting 25% off of gas. unfortunately it was E10 stations. It seemed like we were getting less mpg but it was obvious when we took a drive to my daughters in ohio. we always filled the tank and when we got there, had 1/4 tank left. with the E-10, i had to stop and fill up before we even got to Columbus. we couldnt wait to get rid of those cards.......its supposed to burn cleaner but i wouldnt use it unless absolutely nothing else was available. maybe some of these folks who arent getting good mpg are using E-10.

 

Here in Iowa (yeah...the corn state) E10 is subsidized via reduced gas tax - about $0.10 less per gallon than regular, but the mpg drop with E10 is noticeable.

Nick

 

I just filled up today. Different station and they had E10. I don't know what the other stations use, but the prices for E10 were 10 cents lower than the "going rate." Now we'll watch the mileage to see how it goes.

 

I got gas at a Shell here 2 days ago and noticed the E10 sign on the pump.
First time I put E10 in the car and now know why I have a 3 MPG hit.

 

E10 reduces MPGs 3%; for a Prius that means 1 or at most 2 MPGs. E10 burns cleaner, which reduces air pollution and reduces carbon deposits inside the engine. These are good things and well worth it.

A much better place to direct outrage about this is toward our stupid agricultural policies. Sourcing fuel ethanol from corn is a welfare program for big business and landowners and a distortion of the market. Contact your Congressanimals and tell them to eliminate corn prices supports and the $0.51 import duty on ethanol. Use your home ZIP code to find their contact info here:
Congress.org Home

 

E-10 Creeping into South Florida

38-40 PSI, clean air filter, same commute and cool weather is not a factor here. Yet, during the past few months my average MPG has dropped from 47-48 to 44-45.
The only variable has been the noticable presence of gas pump signs saying "may contain up to 10% Ethanol"

 

Re: E-10 Creeping into South Florida

Yeah, I first remember seeing those at Hess stations back in January, but they seem to be everywhere now. While I have no way of knowing for sure, I tend to read "may" as "does".

I'd love to try a tank of straight gasoline wihout any EtOH to see if there really is a difference.

 

The E10 can account for at most a 2 MPG decrease. The rest is happenstance.

 

i dont know where all of the poster's statistics come from in saying the mpg difference is minimal because i lived the difference. it was over 20% and close to 25%. we drive to columbus all the time and there was no change in driving patterns, side trips on the way, etc. it was a very significant difference. this was on a 2002 buick lesabre that gets 32 mpg highway and 25 city with regular unleaded gas from shell stations exclusively. im not a statitician or an expert on anything except cooking and taking care of house and family. but i KNOW how much extra gas it took to get where we were going when we used E-10.

 

The anti ethanol crowd has lots of bad things to say (big MPG decrease, cause junk to get in fuel injectors etc) but I've been using it on & off since the post MTBE days and have seen (still see) a few percent decrease in MPG but thats it.

 

JYL- if you're interested in conducting your own test there's an EXXON station in Vancouver who's not selling E10 yet. The deadline is dec 1st to switch. I read about this last week in the Oregonian and filled up on Sat.

Snappys Gas & Groceries 10512 Southeast Mill Plain Boulevard Vancouver, Washington, 98664

bl

 

ON my two tanks that I filled with E-10 (I had no choice since I needed gas), I managed 47.4 and 47.7 mpg on E-10 doing my normal driving. Going back to 100% gasoline, I've managed 49.9 and currently am at 50.9 on a fill up from yesterday at 101 miles. So I lost 2 to 2½ mpg on E-10.

I have to avoid the HESS and RaceTrac's / RaceWay's at this time. I still am able to get to Shell, BP/Amoco, and Chevron's without any mileage drop.

 

With Shell e10 I'm getting 45-46 but with the non e10 gas I'm easily getting 51 (similar driving conditions). Not a huge jump but more of a psychological thing for me. I like the 50's.

 

My family and friends have 4 Prius's and 2 other cars. All of us saw that mileage dropped 10 to 20% with E10; In fact in Portland I haven't met a single person who has measured less of a drop with Oregon's recent change. On the other hand you have Ethanol experts like lobbiests, Ethanol farmers, and Oil Companies, who assure you that theoretically E10 should only take MPG down by 3% because that's its measured energy content.

Note that Portland has little difference in temperatures between winter and summer, but the temperature does have about a 5% mpg swing. This is very far from the 12-20% decline we've seen from Ethanol.

This should raise a huge red flag. Why are there NO REAL SCIENTIFIC TESTS? Why hasn't the EPA done a study? Or Consumer Reports? Or any of many universities? Yet we're betting trillions of dollars on these unsupported claims???

I'm afraid there is a horrible story behind this:

1) I think E10 actually does reduce MPG between 10 and 20%. I suspect that Ethanol is reducing the "burn speed" of the gas molecules around it, because ethanol molecules are buring at a lower temperature and therefor damp the burn. Further, Ethanol contains some water on production and easily absorbs more from the air, and that water further reduces the burn temperature. That means that the E10 burn is wasting 20% of the gasoline's energy. Note that just having energy is different that delivering that energy efficiently to drive wheels, so ignore the "3.3% less argument" until it is verified by scientific tests..

2) I think that oil companies saw this was true and concluded that they could make more money with E10 because:
a) it uses more oil in production (up to 100% of its energy value)
b) it theoretically burns cleaner (if you don't count the increased Greenhouse CO2 from burning more)
c) it has a "cellulostic" future to sell the people who realize (a)
d) it actually burns more oil during its use

3) So I believe that oil and big-agriculture company(s) acted to sneak E10 into our gas:
a) they snuck a "waiver" through the EPA during the Reagan years, to prevent the EPA from checking either E10 mileage or E10 pollution.
b) they started sneaking in small amounts of Ethanol (E1, E2 and so on) so that few would notice the mileage drop.
c) they "explained" anomolies like the fact that Consumer Reports Ethanol-based mpg figures (they get gas from their local pump) and the EPA's gas-based figures (they test with chemically tested pure gas).

4) The media has consistently avoided confronting these people, for whatever reason it is that since 1980 the media has become totally Republican/big-biz oriented.

It is time that we check who's right. We Oregonians (and others) who're reporting sudden drops in our mileage, measured consistently since E10 was fielded. Or the people who stand to make billions each year if E10 really does use more gas.

I've written to MoveOn.org and Consumer Reports, as well as many government leaders and universities. No one has shown any study of E10 mileage or pollution.

So let's put it to a real test. With chemically tested fuels, with double blind driving, with multiple sites, and in short scientifically.

Something is rotten in Denmark...

 

I've always wondered why Rutter's gas stations are always priced less than Shell or Exxon in our area. One day I decided to pull in their bays to fill up...but as soon as I saw a large sticker on the gas pump that states..."Gasoline contains !0% Ethanol"...I quickly sped away and went to get my gas at Shell.

 

I believe Shell will be the same.