The U.S. ethanol subsidy policy is once of the great ironically humorous tragedies of the last decade.  A poetic instance of the congressional machine reaching peak momentum and the inability to slam on the brakes once the process was in motion.  It was a big mistake.

I was reminded of all this when, upon pulling into a gas station in Iowa, I discovered that mid-grade fuel blended with ethanol was almost ten cents cheaper per gallon than the low-grade fuel I usually put in my car.  Excited to be burning more cleanly, I almost filled up with the E10.  Fortunately, I had my dad along for the ride to complicate this seemingly easy decision.

“You know,” he said.  “Your gas mileage is going to be lower with the ethanol.”

Great dad. Great.

I am not good at math.  I never have been and, at this point, I doubt I ever will be.  Even if I had at my fingers all the numbers necessary to figure out whether this cheaper fuel would be a) cheaper and b) better for the environment, I still probably wouldn’t have been able to do it.  And I was almost positive that this question was very car specific.  And boy, was I right on that one.

I have a 2008 Honda Fit.  Honda guarantees that the Fit will work with E10.

A rest stop somewhere in Oregon.

Usually, my Fit gets around 35mpg, and I was anticipating getting closer to 40mpg on the trip.  But then I realized I had to stick two people, two greyhounds, a cat, and the crew’s luggage in the car.  So we outfitted it with this thing.

The box.  Otherwise known as –8mpg.

Even with the box, we were packed in like sardines.

“The dogs are touching me!”

However, we did manage to get around 30mpg (sometimes slightly above) for the majority of the trip.  Not bad considering how heavily we were loaded up and how square and wind resistant the box was.

I hate to admit that I was not monitoring mileage closely enough on this trip to notice a significant decrease when using E10.  Additionally, while almost all of our miles were highway miles, the geography varied greatly through the trip.  My little Fit hauled us across plains, across snow covered mountains, and through wind and rain storms.  All of this would have had an effect on the mileage.

However, the general consensus is that using E10 reduces mpg by about 2-3% on the low end, 10% on the high end.  That would reduce my average mpg from just over 30 to just under 30.  Around 29mpg.  At ten cents per gallon cheaper, overall I don’t think I would see a huge difference in my gas bill either way.  (I might be able to do the math on that, but it would take me forever.)

So now emissions – what does it do as far as emissions?  I’m using 2-3% more gasoline to drive the same amount of miles.

The internet has so many answers to this question.  According to this blurb, carbon monoxide (CO) reduction can be 20-30% over regular gasoline.  Yay!  But for CO2 and other GHGs, we’re looking at 2%, which breaks even if I’m getting 2% less out of E10, but is a total fail at 10%.  And for some pollutants, it’s an increase – no good.  But other studies have other numbers, all of which I’m sure are to some extent dependent on the vehicle and the conditions of the test.

Conclusion?  I put E10 in my tank on the road.

However, after reading up, I probably won’t next time.  Financially, it is more or less a break even.  For emissions, it’s up in the air.  But even if it was slightly better on the emissions front, the environmental and economic ramifications of increased corn production for use in ethanol outweigh the benefits.  Ethanol is not a viable solution for our energy issues and is not what I want to be supporting with my hard earned dollars.