In June 2012, the U.S. Environmental Protection Agency (EPA) approved the sale of E15 gasoline, a mixture of 15 percent ethanol and 85 percent gas. (A lower ethanol mixture containing 10 percent ethanol, E10, is already widely sold in the U.S. The E15 fuel blend has been touted as a method of reducing both greenhouse gas emissions and the United States’ dependence on foreign oil, and the EPA says that vehicles built in 2001 or later can run on E15.
However, several automakers and the American Automobile Association (AAA) have disputed the EPA’s claims, maintaining that E15 could damage fuel lines and void vehicle owners’ warranties:
Only 12 million of the more than 240 million light-duty vehicles in the United States are approved by manufacturers to use the gasoline, according to AAA. Automotive engineering experts believe that sustained use of the gas, both in newer and older vehicles, could cause accelerated engine wear and failure, fuel-system damage and false “check engine” lights for vehicles not approved by manufacturers to use E15, according to AAA.
The EPA recommends the use of E15 only in flexible-fuel vehicles and those built in 2001 or later, but critics maintain that even if E15 is safe for most or all cars in that class, many vehicles still on the road (up to 45% in some areas) do not fall within that class, and the newness of E15 means that many drivers could end up filling their tanks with the gasoline, not knowing it’s not approved for all vehicles:
“It is clear that millions of Americans are unfamiliar with E15, which means there is a strong possibility that many may improperly fill up using this gasoline and damage their vehicle,” AAA President and CEO Robert Darbelnet said. “Bringing E15 to the market without adequate safeguards does not responsibly meet the needs of consumers.”
BMW, Chrysler, Nissan, Toyota and VW have said their warranties will not cover fuel-related claims caused by E15. Ford, Honda, Kia, Mercedes-Benz and Volvo have said E15 use will void warranties, says Darbelnet, citing potential corrosive damage to fuel lines, gaskets and other engine components.
The AAA says the sale and use of E15 should be stopped until there is more extensive testing, better pump labels to safeguard consumers and more consumer education about potential hazards.
Proponents of E15 say that the potential danger to fuel lines is overstated and that there’s plenty of time to educate drivers about E15 since only a small number of gas stations nationwide are currently selling the blend.
Bob Dinneen, CEO of the Renewable Fuels Association, says E15 is safe for virtually all post-2001 vehicles, based on extensive government-sponsored testing. “We think the (EPA) warning label should be sufficient to notify consumers,” Dinneen said. “There are no corrosive issues with E15. If there’s an issue with E15 (damaging vehicles) we’re going to know about it, and the EPA is going to know about it.”
Some critics have maintained that because most gas stations don’t want to go to the expense of putting in new tanks just for E15 and will instead likely install blender pumps (which mix the ethanol and gasoline together in the right proportion for the selected fuel type), the possibility exists that an E10 customer who uses a pump directly after an E15 customer might receive as much as a third of a gallon of E15 from residual fuel remaining in the fueling hose, to adverse effect. It is unlikely that such a relatively small amount of residual E15 mixed into a gas tank of E10 could cause problems for standard automobiles, but it may potentially be an issue for gasoline-powered vehicles and equipment with smaller fuel tanks, such as motorcycles, ATVs, chain saws, and lawn mowers. The EPA initially considered heading off this potential issue by imposing a requirement that E10 customers purchase a minimum of four gallons of gas at stations using blender pumps that dispense E10 and E15 through the same hose, but that proposal has since been dropped in favor of requiring labelling on blender pumps stating that such pumps are solely for passenger cars and trucks.