E0 Fuel and its Benefits (So Far)

Some of you may be aware that I am using E0 fuel in my 2012 Prius C 3. This is part of an ongoing experiment to see which is more efficient, and ultimately, which is more economical. E0 fuel is a bit more expensive than the conventional corn based E10, and I wanted to see if the increased cost was worth it. Using Fuelly to keep track of all data related to fuel economy I decided to compare the costs of E0 and E10.

Here's what I've got so far. I only have 5 complete fuel ups with E0 fuel so that was my limiting factor in the number of fuel ups per each. I simply used the data on my Fuelly page for all of the rough stuff. This includes Miles, Gallons to fill up, MPG, Price per Gallon, and Cost per Tank. I did omit one of my E10 fuel ups as the price was skewed due to the transition between E10 and E0. Other than that I simply used the five most recent E10 fill ups, and the five most recent E0 fuel ups for my data.

Over the course of 5 fuel ups for each you can see the stats broken down several ways. I did this in an identical manner for each: Total, E0, and E10. You can see using E0 fuel has increased my mileage by 8 miles per gallon. That's a pretty decent amount in my opinion! All this while cost is in the same ballpark as E10 fuel, with a price difference of $0.0044/mile (on average) I dare say the cost isn't worth worrying about!

So, tell me what you think? What can I do better to make this data more accurate? Note: All of these are just my typical driving to school/work/home etc. None of the tanks I've driven have been for the sole purpose of mileage.

Just in case you're wondering: Tire Pressure is checked biweekly and kept at 44/42. I do use the AC during the day, mornings are pleasant and the AC just isn't needed, so I roll with the windows down. I use Pulse and Glide when I can (traffic and common sense permitting) and I extend my glides as long as possible using the traction battery when under 40ish MPH. I've tried to be as consistent as possible with all of these fill-ups. I have always used the same pump (except when going from E10 to E0 of course) and I always pump with the lowest auto-dispense setting on said pump until first cutoff. For S's and G's I have also been logging the Indicated MPG's on the screen in the car, and have noticed they are always in the ballpark of +2MPG's over calculated mileage.

Also for what it's worth, all E10 fuel was 87 Octane. All E0 fuel was 90 Octane. Not sure what weight if any that holds in these results, but it's a data point I thought I'd make you aware of.

 

No kidding. This would be great. Meat prices would go down, corn prices would go down, anything with corn in it, prices would all go down. Doesn't make sense to take your food sources, and burn them (literally).

 

I don't really see the attraction.. Why put something in your fuel that causes it to be less efficient? If you get better mileage without ethanol, you use less fuel.. Same with the emissions stuff nowadays. Older cars got better mileage without it, but were "more harmful." I would think if your car is more efficient without that stuff it would put less emissions into the air.. I just don't get why they make the fuel less efficient instead of more efficient, that way all cars make the most of what they burn.. But what do I know?

 

If I could find a station that has it, I would. Here they go from 87 to 89, then 91. But as was stated earlier, the octane is just a rating of resistance to early combustion. I was simply stating the discrepancy between the two fuels in my first post because they are different, and the car manual states the use of 87 octane is recommended.

If I could have my way, I'd run 87 octane E0 fuel. But it doesn't work that way unfortunately.

Yes indeed it is less. $0.0044/mile less. To me, the difference doesn't equate the use of E10 over E0, especially considering the drawbacks of ethanol. Me? I just chock the additional less-than-half-a-penny per mile as a convenience thing.. Don't need to go to the gas station as often, plus it's better for the vehicle in the long run.

I am also planning on more testing once I receive a Scangauge. I am curious to see what horsepower differences E0 fuel has over E10. I feel like the car runs better, but can't really back it up with any proof as of yet. I think it would be extremely neat to experiment with the car on a Dyno.

What I'm not understanding is why I have an increase of 8 MPG's with Ethanol free fuel. General consensus is that it only boasts a 2% increase in mileage which equates to 1.6 MPG's at best.. So there is something going on. The only thing I can think of that may artificially increase this number is the fact that my most recent tanks have been E0 fuel, whereas the E10 tanks are all with less seat time (and therefore less experience and familiarity) with the car.. I don't really know if this plays a big role but I would like to think the more I am behind the wheel of my Prius C the better I get at managing it and knowing how it works. More testing in the works. I just wanted to put this data out there to see what you all thought and to see what changes I should make to my system.