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U Of M Study Finds Ethanol Worse For Air Quality Than Gasoline

MINNEAPOLIS (WCCO) – For years, the state's corn and ethanol industries have touted the environmental benefits of burning the alternative fuel in our vehicles.

But newly released research from the University of Minnesota College of Science and Engineering is raising eyebrows.

The study compared pollution levels from gasoline fuel and 10 alternative energy vehicles, including hybrid electric, natural gas and corn-based ethanol.

One of the most surprising findings is that ethanol might actually be worse for air quality than conventional gasoline fueled transportation.

Researchers looked not only at the end result at the tailpipes but also took into account the full cycle of energy production. For instance, the authors calculated the entire pollutant stream, meaning everything generated from the growing of the corn to the process used to turn it into ethanol.

In addition, they extrapolated the pollutants of electric vehicles when the electricity used to recharge the batteries is generated by the burning of coal.

"And we found that some options available to us, like corn ethanol or electricity from coal used in electric vehicles, actually make the air much worse," assistant professor Jason Hill said.

Professor Hill is one of three authors of the study.

Their research actually finds that the pollutants from both ethanol and gasoline are nearly equal at the tailpipe.

But it is when you take into account the energy used to make the ethanol that the notion of a "cleaner burning" fuel is called into question.

"That is not true. In fact, corn ethanol is about twice as damaging to the air quality as gasoline," Hill said.

One factor is that there is less energy produced in burning the equivalent amount of ethanol as compared to gasoline. A vehicle has to burn more of it to get the same amount of horsepower power.

But the additional pollution generated by the farm machinery used to plant, fertilize, cultivate, combine, dry and transport corn to the ethanol plants will contribute to the fuel's negative air quality impacts.

In addition there are the pollutants generated in the processing of the grain into ethanol.

But the Minnesota Corn Growers Association disputes the findings and says it does little to hurt our overall air quality.

"It doesn't help, that's for sure," MCGA's Adam Czech said.

In fact, says Czech, ethanol blended fuels have improved air quality in the state and are a big reason Minnesota is no longer on the EPA's air quality non-attainment list.

"We just keep pushing the actual science and the actual consensus within the academic and scientific research community of ethanol's benefits," Czech said.

Besides the corn growers, the Minnesota Bio Fuels Association is also critical of the study.

Both groups cite other scientific research that they say support corn ethanol's benefits.

As far as electric vehicles are concerned the U's study finds that the beneficial impacts vary greatly, depending on the source of the electricity.

In fact, the study finds that driving an electric car is actually worse than gasoline if the power used to recharge the batteries is generated from coal.

It's only clean electricity like solar and wind that give electric vehicles their benefits.

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