It's not uncommon to find gasoline blends for sale comprised of 10 percent ethanol, but some groups are lobbying for an E15 blend - made of 15 percent ethanol, 85 percent gasoline - to be the new norm.
Although high concentrations of ethanol (like E85) theoretically offer a "greener" fuel than pure gasoline, low doses of ethanol in gasoline are typically used to boost octane levels and reduce the fuel's propensity to cause engine knocking. The E10 blends currently sold in many parts of the U.S. are typically safe for use in all vehicles without specialized systems.
E15 - the fuel standard proposed by a consortium of corn-growing states - would likely not be safe for use. Ethanol is quite corrosive, and in order to create a vehicle that can safely use the substance, automakers have to design specialized fuel systems (e.g. tanks, lines, pumps, injectors, etc.) designed to resist the alcohol. Although a number of cars today are "flex fuel capable" and can run up to E85 blends, many - especially older vehicles - are not. Using such fuels in vehicles incapable of handlingthem can cause extensive, expensive damage.
Still, Congress has mandated that 11 billion gallons of ethanol be consumed by next year, withthat number growing to 36 billion gallons by 2022. Mike Stanton, the CEO of the Association of International Automobile Manufacturers, told The Detroit News that even if every pump in the U.S. sold E10, we could not even consume half of that 36 billion gallon figure.
While the two sides continue to argue for their position, the U.S. Environmental Protection Agency has until December 1 to decide whether or not to change the base fuel standard.
Source: The Detroit News