E-15: Life in the Fast Lane

September 5, 2013

Dave Juday, September 4 – There is a debate ongoing about the efficacy of so-called e-15, i.e. motor gasoline blended with 15 percent ethanol.  The standard blend has always been 10 percent ethanol.  While the Environmental Protection Agency (EPA) granted final approval for e-15 in June 2012 for use in late model cars and light duty trucks, the American Automobile Association has cautioned, “this new fuel entered the market without adequate protections to prevent misfuelings and despite remaining questions about potential vehicle damage, even for EPA-approved 2001 and newer vehicles.”

Such concerns are nonsense says the ethanol trade association Growth Energy.  The testing by EPA was “exhaustive,” there are misfueling labels required for pumps, and “additionally, NASCAR has run on … a fuel blended with 15 percent ethanol for over four million miles.”

This last point should give pause.  Are the engines used in the professional stock car racing circuit a fair proxy for the family auto?  For driving conditions?  Is it even really the same e-15 fuel?

The fuel is different.  NASCAR switched to e-15 in 2011 and uses a version that has a 98 octane rating.  Retail e-15 has an octane rating of 90.  Regular grade gasoline available commercially has an octane rating of 87; premium grade is 93.