What’s Good to Know about E10 and E15 in Your Tank

Did you know that 10% of nearly all the gasoline sold retail in the U.S. consists of ethanol? Not long ago, I thought that any of the Es – E10, E85, etc. – referred only to vehicles capable of handling that much ethanol, basically flex fuel vehicles. I did not understand that in recent years, our gasoline – not just in California, or some corn growing state like Iowa – became 10% ethanol. And now the EPA is cool with going up to 15% on 2007 model year or newer vehicles.

Boy, do I feel dumb. And I’m the editor of Automotive Digest Green. Here’s a few other things I’ve learned about E10 and E15…

•E10 and other blends of ethanol are considered to be useful in decreasing U.S. dependence on foreign oil, and can reduce carbon monoxide emissions by 20% to 30% under the right conditions.

•Much of this stems from the Energy Independence and Security Act of 2007, where the Renewable Fuel Standard program was expanded to increase the volume of renewable fuel required to be blended into transportation fuel from nine billion gallons in 2008 to 36 billion gallons by 2022. Corn ethanol can make up much of this volume, and other sources will include advanced biofuels possibly coming from cellulosic ethanol and algae biofuel.

•Environmental groups have voiced strong opposition to the effort to increase use of ethanol because production of the fuel – made from corn in the U.S. and from sugar cane in Brazil – is environmentally damaging and can lead to a reduction in land devoted to growing food crops.

•Archer Daniels Midland, the top publicly-traded ethanol maker, is supportive of higher ethanol blends, and its shares rose to near a record high last week after the EPA’s E15 announcement.

•The EPA’s decision, for the time being, to limit E15 usage to 2007 model year or older vehicles has been criticized by the Renewable Fuels Association, a major trade association for the US ethanol industry. The association accused the EPA of missing an opportunity to reduce America's dependence on foreign oil and create new economic opportunity.

•Exxon Mobil’s vice president of government and public affairs, Ken Cohen, blogged and said the E15 decision could have unintended consequences. He noted that federal Renewable Fuel Standards require eventual use of up to 36 billion gallons of biofuels (versus about 12 billion produced and consumed today) and said that to meet those goals by 2022, the blends of ethanol might have to be extended as high as 20 to 25 percent.

•Critics of the higher blend E15 have said it would cause damage to older motor vehicle engines, as well as small engines used for motorcycles, tools, lawn mowers, and outboard marine motors.