Monday, March 17, 2008
Mileage decrease from mixing E85 in Saab 9-3
Ethanol has an energy content of 82529 BTU/ gallon. Gasoline has an energy content of 114,000 BTU/ gallon. From that, I calculated the energy content of the actual mixture in the tank, and used that to determine how much less mileage you would get on a % basis.
Obviously, this is going to decrease your mileage a bit. In my case, a 6% decrease works out to be about 1.5 mpg, which is not a big number. I can cause a decrease in mileage more than that by just my driving technique.