Comparison: E85 Ethanol vs. E10 Gasohol
Two of the most common fuels containing ethanol are E85 and E10, which is often referred to as “gasohol” because of its greater gasoline content. The number after the letter “E” refers to the ethanol percentage in the fuel, with the remainder consisting of gasoline. Both types offer some benefits and drawbacks.
VEHICLES: Gasohol can be used in just about any gasoline powered vehicle, while E85 is limited to flex-fuel vehicles, which can run on E85, gasohol, or gasoline. According to hawaii.gov, “all gasoline powered cars sold in the United States “can use gasohol with up to ten percent ethanol content”. There are a variety of flex-fuel vehicles available from a number of different brands, especially in recent years.
EFFICIENCY: Fuel efficiency (miles per gallon) is reduced as the percentage of ethanol increases; according to cleanairtrust.org, gas mileage decreases slightly when E10 gasohol is used, and more substantially for E85 ethanol. However, it also states that researchers are working on methods of improving the efficiency of ethanol, and E85 is cheaper due to its higher ethanol content.
AVAILABILITY: It is difficult to determine just how many gasohol stations there are, but they appear to be more common than E85 stations. According to the Wisconsin Legislative Reference Bureau (2005), the states of Montana, Minnesota, and Hawaii have required or plan to soon require that all gasoline be replaced with 10% gasohol. The East Tennessee Clean Fuels Coalition website indicates E10 stations are the most common alternative station type in eastern Tennessee. GasWatch.info can be used to monitor the price of E85 in your area, along with regular gas and other fuels.
Overall, gasohol is available at more stations and can be used in a greater number of vehicles, but E85 produces fewer emissions and costs less.