E-15: Life in the Fast Lane

by Marlo Lewis on September 4, 2013

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Guest Post by Dave Juday

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.

Driving conditions, of course, are different.  NASCAR winners so far in the 2013 season have logged average speeds of 153 miles per hour at the Brickyard in Indianapolis, 144 miles per hour at Michigan International Speedway, and 129 miles per hour at Pocono Speedway.  Is that a model for the average morning stop-and-go, engine idling commute?

The engines are different.  Consider, the top selling model in the US for 2011 and 2012 was the Ford F-Series pick-up truck which come with V-6 or V-8 engines that range from 302 to 360 horsepower respectively.  For passenger cars, the top seller in 2012 was the Toyota Camry.  The Camry has two engine choices – a 2.5 liter four-cylinder which produces 178 horsepower, or a 3.5 liter that has 268 horsepower.  The average NASCAR engine makes about 750 horsepower.

Even the standard for mixing the ethanol into the gasoline is different.  Commercial e-15 is mixed to 15 percent ethanol by volume; NASCAR’s fuel is 15 percent ethanol by weight.  Weight is a more precise measurement.  In fact, NASCAR teams are provided with the exact density of the fuel on the day of the race measured to the second decimal place, or one one-hundredth of a percent.  That makes sense for race cars, which in making a mile-long lap, may use a quart of fuel.  Running out of fuel one-quarter lap too early – and losing the race – can be extrapolated to being one cup short of fuel.

The point being, there is an unparalleled precision used in auto racing.   Fuel is delivered to race tracks by dedicated tanker, it is transferred by specially trained personnel into cans that are specially designed to limit moisture, which in turn are used by trained pit crews to fill the car’s tank.  Compare that to e-15 at a self-service gas mart, which is stored in an underground storage tank and pumped through a blender pump that handles other fuel mixtures ethanol and then sits in vehicle’s gas tank for a week or more.

When NASCAR tested e-15 in its engines, the engines were all the same.  NASCAR as a sanctioning body for racing has certain engine specifications.  Moreover, the tests were for performance.  Those engines were then tweaked to take advantages of certain properties of e-15, like higher octane.  When the US Department of Energy tested e-15, it was testing for exhaust and emissions standards and was applied across a wide range of engine types. (NASCAR was still using leaded fuel until 2007).  Ultimately, EPA used this testing data to approve e-15 use in about 50 percent of all automobiles on the road.

As the American Automobile Association notes, engine life, fuel pump performance and other factors are risks from e-15 that the federal testing was not structured to measure.  Furthermore, the group reports that only five percent of all auto warranties cover the use of e-15.  That leaves a huge gap compared to the 50 percent of vehicles EPA says may legally use the fuel especially considering the warning label on the pump may not be an adequate protection from misfueling.

Success with race car engines notwithstanding, there are many potential issues for everyday drivers and their vehicles that the race to commercial adaptation of e-15 pose.   The yellow flag for caution should be waved until these issues are cleared.

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