10% Ethanol gas cuts mpg ?

I normally fill up at Shell stations. They say their gas contains up to 10% ethanol, but I don't think anything of it. It does make the MPG marginally lower, I think, but it's not too noticeable in my opinion. Can you buy ethanol-free gas in your area? Your best bet would be to try that out. It's usually more expensive, but you never know. I've never used "ethanol-free" gas and always get 56+MPG calculated per tank - depending on the conditions/trip length. In short, yes it may have an effect, but I don't think it's too dramatic. Try to buy from top-tier brands (I don't think Costco is one) such as Texaco, Shell, or Chevron who put fuel additives in their gas such as Techron. It'll help the ethanol not gunk up your engine as badly, just a thought!

 

Yes, there is less energy in E10 fuel but you can still get excellent fuel economy with it. You cannot compare your car to someone else's when they have a completely different commute and conditions.

You won't find any 100% gasoline in California without going to specialty shops that sell race gas. LOL

 

I guess I wondering why it matters. You can't get non-ethanol fuel here so you cannot change your fuel type. You could change your driving techniques and route which is much more beneficial than non-ethanol fuel. Personally I wouldn't sweat it. The difference is fairly small and most places charge more for it so the savings in mpg don't cover the extra cost.

 

Looking at energy density Energy density - Wikipedia, the free encyclopedia

Gasoline has 34.2 MJ/L
Ethanol has 24 MJ/L

E10 calculates to 33.18 MJ/L or 3% lover energy content. But question is how correct are these values for gasoline. Here in EU gas should have at least 42.7 MJ/kg or only 31.4 MJ/L no one knows how much more are we getting on the gas station. I think all gas here is at least E5.

 

I can answer from a non-hybrid experience. Last year I traded an '09 Corolla S that I drove +120 miles round trip from Oak Ridge to the Smoky Mtns daily. At one point early on, the ethanol was only used during the "blend seasonal" months. During the non-ethanol period, I got routine hand calculated mid 39mpg running at ~65mph. When the ethanol was added, the hand calculated mpg dropped by an average of 2.5 mpg. The last year or so of the Corolla use, ethanol was used 100% of the time. I agree with previous posts that the regularly sold "we don't have ethanol" stations cost then +$0.10 more per gallon and was not worth the extra cost for the gain of 2.5mpg.

Yes, with that small 4 cyl, you could notice less "on ramp" performance using ethanol.

It would make sense that even though the Prius does not have a normal drive train, that the ethanol would still make some minor efficient run of the gas motor electric generation. What that drop in efficiency would be worthy of some one taking on that challenge.

With no hub caps, constant AC use, average driving on I75 (65-70mph), ethanol blend and efficient use of battery only in our community and local driving, I am quite satisfied with my 48/49 mpg .... :>))

Regards,
radmangto

 

3.3% (that is the amount that of BTUs that E-10 has less than 100% gasoline)

My Prius is getting around 58 MPG at the moment. Yes, the EPA uses (requires) 100% gasoline, but that is the least of the causes for the difference between their results and real world results.

 

I have access to both E10 and E0 gas in my area. Most of the stations that (say that they) offer "real gas" are the smaller Mom and Pop stations that charge 10-15 cents more than the bigs. They also generally have much older pumps and tanks, if you're worried about that kind of thing.
Back when I first got 'my' G3 (it's a company car) and I was in my hypermiling phase, I tried to quantify the difference between E0 and E10. It's not as easy as you may think, since there are always differences in tank MPGs due to routing, temperature, wind, traffic patterns, how many bugs there are, etc....
I didn't see much of a difference at all, and I always measure my tank-to-tank MPGs by hand, at the pump, and I almost always fill the car at about DTE minus 50 or so (meaning about 50 miles past the point where the &^$#! stupid MDF says you're at zero miles.)
The reason I do this is is that this enables me to put exactly 10.0 gallons of fuel in the car consistantly, so that my tank MPG measurements are more accurate.
In my car, if I try to fill up at DTE=0, I can only put about 9.5 gallons into an 11.something gallon tank. That's Toyota for you...

Anyway....I haven't seen enough of a difference in my car to worry about it at all, so I stopped doing so about a year ago. I suppose in a lab, with your car strapped to a dynomometer you could "measure" a difference between E0 and E10, but you know what your "real world" efficiency is when you're driving in a lab?
Right.
It's zero, because you're not really going anywhere.

Bottom line: If you live in one of the more 'enlightened' states where you have no choice between E10 and E0, then you might as well not worry about it. Your government has already solved that problem for you.
And...
If you think that those of us who live in areas where the citizenry has a choice are getting over on you by putting E0 in our cars, then you can rest well assured that from an economic standpoint, it's simply better running E10 in your car anyway----just like the OEM says that you should.
Most of the crap that you hear in the modern "automotive temperance movement" is (IMHO) just that. Crap. To me...it's no different that the FUD that was swirling around Hybrids when they first came out.
Most of the corn that is grown in the United States is used as silage (feed) to fatten up cows to make your steaks taste better, or it gets turned into HFCS to fatten up your kids cause it makes everything else taste better.
If we're going to grow lots and lots of corn? Probably one of the better uses for this crop is to turn it into automotive fuel, but that's a sidebar.

If you live in a state where you can get E0, by all means buy and use it! Mom and Pop gas stations need customers too.

As they always say.......YMMV!

 

Most stations here in Nebraska offer E10 and E0 with the E0 costing 10-15 cents higher. I usually try to get the E0 and I notice a little increase in FE. 3-5% is the range I've heard thrown around.

Kinda weird IMO that a lot of our crops in NE go to make ethanol but yet it's not mandatory here like many other states.

 

Using E0 instead of E10 = 3% MPG increase
Slowing down from 70 mph to 55 mph = 20% MPG increase.

 

Rich,

Your commute and driving habits do play a big part in your MPG's. I'm in Northern California as well, but have a pretty darn good commute that is condusive towards getting high MPG's. Yes, it is suspected that E10 will decrease the amount of MPG's you get, due to the lower amount of energy present (and by the same token, diesel contains about 10% more energy than 100% gasoline).

Point is, your commute and commuting habits impact your MPG's much greater than the type of gas used. 10% Ethanol is below max PSI tire pressure on the list of "bang for the buck".

In some particular order fix these

Driver habits (speeding, coasting to stops, tailgating, fast starts)
Commute habits (combine trips, try to find routes with lower speeds, less stopping, avoidance of hills)
HVAC maintenance in the car cabin.
Car care (grill block in cool months, max inflation of tires)
Gasoline (can't help you in CA)

 

I think it's changing next year. I know here in the UK as of 2013 all petrol will be able to contain upto 10% ethanol without it being disclosed. Presently the limit is upto 5%, though there are reports of some owners in certain areas suddenly noticing a drop in mpg's when using certain cheaper petrol (mainly a certain supermarkets), so it could be that with only 5 months to go, so suppliers have already introduced it.

 

One point that has not been mentioned yet....
Using E5 or E10 effectively forces drivers to buy more gas, which increases tax revenues for the state.

 

Unfortunately, "pure" gas costs 15 to 20 cents more per gallon, is unbranded even if sold at a known brand station, and any MPG benefits fall within the margin of error since other factors outside a dynamo under controlled conditions will affect your results. I want to know that what I put in my tank is clean and safe for the car!

 

If the EPA did use 10% Ethanol gas in their testing for MPG's the Prius would
not have a EPA rating of 50 MPG, it would be more like 47 MPG or so.

 

So you are saying there is a 6% hit compared to the 3% hit others are saying?

 

I only had the chance to use 100 % reg. gas a couple of times when I was in Reno Nevada.
Oregon does not have regular unleaded gas with no Ethanol, and requires a 10% blend
in regular gas.

The times I did use regular gas with no ethanol I at least gained 3 more mpg, the car
seemed to have more power.

I am sure other forum members can chime in on the use of pure gas compared
to 10% Ethanol blend.

 

I remember a similar experience when my 1990 Honda Accord LX sedan (Auto) mpg dropped from 24 mpg to 22 mpg (city-suburb commuting) after 10% ethanol gas was mandated for my metro area. In general terms, a conventional gas vehicle when driven normally will see a dip of about 8% loss in mpg with 10% ethanol gas over 100% gasoline depending on driving conditions and how a vehicle is driven.

 

If you replaced the 10% ethanol with 10% absolutely nothing, you would see a 10% drop in gas mileage (as compared to 100% gasoline). If the gas mileage drop you are seeing is near that (and I have seen people claim more than that!) something is definitely wrong, at very least with our understanding of ethanol combustion in car engines (and race cars which use 100% ethanol should not be able to move at all).

Given that, I would like to see claims backed up with data, and rigorous scientific method.