Question: How Does Ethanol Performance Compare to Gasoline?
Ethanol is widely available and reasonably inexpensive, but what kind of performance can drivers expect from a car running on ethanol or an ethanol/gasoline blend?
One gallon of pure ethanol contains about 66 percent as much energy as a gallon of gasoline. A gallon of E85, a common blend of 85 percent ethanol and 15 percent gasoline, contains about 71 percent as much energy as a gallon of unblended gasoline.
Drivers who use E85 can expect about 15 percent less fuel economy than they would get with gasoline. Other performance factors such as power, acceleration, and cruising speed are essentially equivalent in vehicles burning E85 and conventional fuels.
Ethanol: Frequently Asked Questions