You may be aware of the recent availability of a new blend of gasoline – known as E15. E15 (15% ethanol, 85% gasoline) is a higher octane fuel available in 23 states at retail fueling stations. In October 2010, the U.S. Environmental Protection Agency (EPA) approved a waiver permitting the use of E15 (85% gasoline/15% ethanol) in model year 2007 and newer autos and light duty motor vehicles. In January 2011, the EPA extended the waiver to permit the use of E15 in 2001 to 2006 model year autos and light duty vehicles. Of course, Flexible Fuel Vehicles (FFV) are permitted to use E15. This waiver ruling was made after many years of extensive tests, making E15 one of the most tested fuels in history prior to its permitted use. (A lower ethanol mixture containing ten percent ethanol, E10, was already widely being sold in the U.S.)
The E15 fuel blend is being touted as a method of reducing both greenhouse gas emissions and the United States’ dependence on foreign oil, and the EPA has asserted (based on a 2011 study by the Department of Energy) that virtually all vehicles built in 2001 or later can safely run on E15.
It is important to note that dispensing E15 into a vehicle or engine that may not use E15 is prohibited by federal law. Vehicles that may not use E15 are model year 2000 and older cars, light-duty trucks, and medium-duty passenger vehicles. All motorcycles may not use E15 as well. Other engines that may not use E15 include: all off-road vehicles, including boats and snowmobiles, all off-road equipment, including lawnmowers and chainsaws, and vehicles with heavy-duty engines.
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 in many cars, particularly vehicles manufactured prior to 2012. The Renewable Fuels Association, a leading proponent of the newly available E15 blend, says that although vehicle owner’s manuals for the 2001 through 2012 model years may not offer guidance on the use of E15 since it was not an approved fuel at the time those vehicles were manufactured. They recommend that owners of vehicles built during those years check directly with the auto manufacturers or an authorized dealership for guidance on using the new fuel. The owner manuals of 2012/2013 and later model year vehicles will likely provide guidance on the use of E15 in those vehicles.
There has also been a lot of misinformation about ethanol blends since they started to be come more widely available. Fuel system problems, hard or no start conditions, rough idle and a whole variety of ills have been communicated in various places over the years.
A section of The Energy Independence and Security Act of 2007 directed the DOE (Department of Energy) to assess the feasibility of using intermediate ethanol blends in the existing vehicle fleet. Evaluated by the National Renewable Energy Laboratory (NREL) and in a preliminary 2008 report, the NREL described the effects of E10, E15 and even E20 on tailpipe and evaporative emissions, catalyst and engine durability, vehicle driveability, engine operability, and vehicle and engine materials.
This report found that NONE of the vehicles displayed a malfunction indicator light, no fuel filter plugging symptoms were observed, and no cold start problems were observed under laboratory conditions.
Consumer Reports interviewed a Detroit-based automotive engineer at the time that this rule was proposed by the EPA and said that automakers will have trouble making non-flex-fuel vehicles comply with emissions requirements, if the ethanol levels in a vehicle’s fuel tank are inconsistent.
Today’s ten-percent standard is the maximum allowable, but lots of gasoline may be blended at seven or eight percent to stay safely below that cap. These variations can confuse the oxygen sensors in a car, which can make the fuel injection overcompensate and produce more pollution or even rough-running.