E85 produces 27 percent less energy per gallon than gasoline, so on average it ends up costing more.
For example, the flex-fuel 2010 Chevrolet Impala equipped with a 3.5-liter V-6 engine gets an EPA-estimated 18/29 mpg (city/highway) on gasoline and 14/21 mpg when burning E85. The acceleration is pretty much the same, but the car's range is shortened. In other words, you'll be filling the tank more often when using E85.
Do the math and you'll discover that E85 must be priced roughly 28 percent less than gas just to break even. For example, if gasoline is $3 per gallon, E85 would have to be priced below $2.16 per gallon. There are regions in the Corn Belt where E85 reaches this threshold, making it cost effective.
