Study Finds E20 Blends Reduce CO and Hydrocarbon Emissions in Automobiles

A recent study by the Center for Integrated Manufacturing Studies at Rochester Institute of Technology indicates that the use of E20 fuel (20% ethanol, 80% gasoline), reduces tailpipe emissions of hydrocarbons and carbon monoxide, compared with conventional gasoline or E10 blends. In addition, the research team found no measurable impact to vehicle drivability or maintenance in conventional internal combustion engines.

The RIT team, which was also led by Brian Duddy, a senior program manager at the Center for Integrated Manufacturing Studies, worked with the County of Monroe, N.Y., to test the use of E20 in 10 older gasoline vehicles that were not designed for ethanol fuel mixtures. The study utilized service vehicles used by the county, which logged more than 100,000 miles on E20 fuel and were analyzed periodically both for emissions and overall wear and tear on the vehicle.

The fleet showed an average emissions reduction for carbon monoxide of 23% as well as a 13% reduction for hydrocarbon emissions, compared to conventional gasoline, with no measurable stress on vehicle operation or mechanics.

The data illustrates the potential benefits of E20 as a tool in reducing overall vehicle emissions at a time when many states and the US Department of Transportation are considering policies that would increase the ethanol percentage in standard gasoline.

The study results were published in the Journal of Automobile Engineering and are being used by the Environmental Protection Agency to promote the federal Renewable Fuel Standard program. This effort has mandated an increase in the volume of renewable fuel required to be blended into transportation fuel from 9 billion gallons in 2008 to 36 billion gallons by 2022. The RIT team is continuing to work with Monroe County to convert their entire conventional gasoline fleet to E20 and will provide additional analysis on the impact of ethanol on long-term vehicle durability.

Resources

• Brian Hilton and Brian Duddy (2009) The effect of E20 ethanol fuel on vehicle emissions. Journal of Automobile Engineering Volume 223, Number 12 doi: 10.1243/09544070JAUTO1188