Study Says Ethanol Pollution Could Rival Gas A new study from Stanford University suggests that pollution from ethanol could be even worse than from traditional gasoline. Study author Mark Jacobson, of Stanford's department of civil and environmental engineering, explains.

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Study Says Ethanol Pollution Could Rival Gas

Study Says Ethanol Pollution Could Rival Gas

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A new study from Stanford University suggests that pollution from ethanol could be even worse than from traditional gasoline. Study author Mark Jacobson, of Stanford's department of civil and environmental engineering, explains.


This is DAY TO DAY. I'm Alex Chadwick.


I'm Madeleine Brand.

Coming up, the worst school shooting before Virginia Tech has an anniversary this week. We speak with the principal of Columbine High School.

CHADWICK: First, with all the news about climate change, ethanol - that's fuel from corn - is supposed to be one answer. But now a study from Stanford University says ethanol pollution may be worse than gasoline. The problem is a byproduct of burned ethanol, a type of ozone.

Ozone is good when it's high up in the atmosphere, says the study's author Mark Jacobson, but it's very bad when it accumulates near the surface of the earth.

Prof. MARK JACOBSON (Author of Stanford University study on ethanol): It corrodes statues, it breaks down rubber. It also corrodes our lungs, causing respiratory illness and bronchitis and asthma. So there's - the bad ozone is what's being affected here by both gasoline and ethanol vehicles.

CHADWICK: So there would be more of this produced, you think, from using ethanol as a fuel?

Prof. JACOBSON: What we found was that in certain parts of the country, in fact most of the country - like in Los Angeles, in the northeastern U.S., in parts of the Midwest - you get increases in ozone due to converting to ethanol. If you weighed the changes in ozone by the population distribution of the U.S., you get a net increase in the death rate and hospitalization rate due to ethanol.

CHADWICK: So this surface ozone, I think you might call it, is this just simply a part of the process of producing ethanol, a natural byproduct, or is there some way you could filter this and get rid of it?

Prof. JACOBSON: Ozone that's formed is formed from the emissions of either ethanol vehicles or gasoline vehicles. And there - or have been technologies that have been introduced that have reduced the amount of ozone significantly. For example, the catalytic converter reduced the ozone. And there are other technologies that potentially could be used to reduce ozone further.

In fact, in this study we assumed there are going to be technological improvements. Just to put in perspective, gasoline vehicles in the United States kill about 10,000 people prematurely each year. Now, if we convert to ethanol, what I found was that this might increase slightly by about 200 deaths per year.

So it's not a large increase over gasoline. But the key is it's not an improvement over gasoline as has been suggested. The key is whether we can do a lot better than gasoline. And there are technologies out there that could eliminate all these deaths, particularly, battery electric vehicles where the electricity is provided by renewable energy such as wind and solar power. And also hydrogen fuel cell vehicles where the hydrogen is produced by wind and solar power and also hydroelectric geothermal power.

CHADWICK: I'm thinking beyond the scientific arguments to the political arguments. There is a huge, huge political base in this country in farming state for ethanol.

Prof. JACOBSON: On its own, if people want to use more ethanol that might be OK, but I would suggest not to use the argument that it benefits climate or it benefits air pollution. And particularly air pollution, because it simply does not benefit air pollution using ethanol.

And in terms of climate, the latest study shows - and that's out of U.C. Davis - that there's only a 2 percent difference in the net carbon emissions between ethanol and gasoline, which is virtually negligible - when the ethanol comes from corn.

CHADWICK: Mark Jacobson, when you publish this paper and you listen to the arguments and the predictions and the cost estimates and all that, why do you think we are where we are today where we seem to have arrived at ethanol as the answer?

Prof. JACOBSON: Well, the reason is is because there are a lot of people who have not been studying the subject for very long who are arguing in favor of ethanol and other types of solutions to climate change and also air pollution. And most of these people don't have a lot of background in this area and so aren't familiar with many of the issues.

Now, as somebody who's been working on this for many years looking at climate change and air pollution and energy issues, I can see that the solutions that have been proposed have many weaknesses to them. What I find is that a lot of this is driven by interest groups that - lobbyists in particular - and not driven by science.

So many times the scientists are not being listened to and instead it's the lobbyists who are being listened to, the venture capitalists in particular, but also lobbyists for particular industries.

CHADWICK: Mark Jacobson is an associate engineering at Stanford University. His article in the journal Environmental Science and Technology is out today. Professor Jacobson, thank you.

Prof. JACOBSON: Thank you very much.

(Soundbite of music)

CHADWICK: And NPR's DAY TO DAY continues.

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