What is E10?

E10 is 10 percent ethanol and 90 percent unleaded gasoline.

This 10 percent ethanol blend is covered under warranty for every make and every model of automobile produced by every automobile manufacturer that sells vehicles in the U.S. Many even recommend its use because of its high octane and superior performance characteristics.

How do I know if I’m getting ethanol-blended fuel at the gas station?

Some, but not all, gas pumps will be labeled with the amount of ethanol contained in the fuel. States determine whether they have mandatory, voluntary or no pump labeling laws.

Where can I buy ethanol-blended gasoline?

Because ethanol-blended fuel is becoming more popular, the real question is the opposite: Where isn’t ethanol-blended fuel sold? Ethanol-blended fuel is sold extensively throughout the Midwest, where most of the country’s ethanol is produced. In Minnesota, for example, every gallon of unleaded gasoline contains 10 percent ethanol. With the national phase out of MTBE, ethanol is also used in East and West Coast markets.

Do people ever use more or less than a 10 percent ethanol blend?

Yes. E15, which is 15 percent ethanol and 85 percent unleaded gasoline, is readily available in many areas of the country. Also, many flex fuel vehicles can run on E85, an alternative fuel that is 85 percent ethanol and only 15 percent unleaded gasoline. However, the vast majority of the nearly 13 billion gallons of ethanol used annually in the U.S. is E10, the 10 percent ethanol blend.

What does the term oxygenate mean?

Ethanol is an oxygenate, meaning it adds valuable oxygen to the gasoline. More oxygen in a fuel allows it to burn more completely and cleanly. Ethanol is 35 percent oxygen by weight, so a 10 percent ethanol blend produces gasoline with 3.5 percent oxygen. Oxygenates are required in some areas of the country with air pollution concerns.

What is the octane level of ethanol?

Pure ethanol carries an octane rating of 113, so adding 10 percent ethanol to unleaded gasoline will raise the fuel’s octane rating between 2 and 3 points.

Is ethanol a new product?

No. Ethanol, at its most basic, is grain alcohol and has been around for centuries. Henry Ford envisioned his automobiles running on this type of alcohol rather than gasoline.

Can E10 be used in small engines?

Yes. Ethanol-blended fuel is safe to use in small engines like motorcycles, lawn mowers, trimmers, boats, personal watercraft, snowmobiles, ATVs and many others. Manufacturers understand that a considerable portion of the gasoline sold in this country contains ethanol and ensure that their products are compatible with oxygenated fuel.