Ethanol fuels rumor mill, but experts say E10 is safe
(Published Wednesday, May 9, 2007 11:41:42 AM CST)
A d v e r t i s e m e n t
By Stacy Vogel Gazette staff
In a time when ethanol has become a household word, Manish Dadwal proudly advertises that the substance is nowhere to be found in his regular gasoline.
"100 percent gas. No ethanol," reads the sign over the Mobil gas station Dadwal owns at 1215 Milton Ave.
Dadwal isn't opposed to ethanol. In fact, his station is one of two in Janesville that offer E85, the combination of 85 percent ethanol and 15 percent gas made for flex-fuel vehicles.
But unlike many gas station owners, he refuses to add ethanol to his regular unleaded, saying it's bad for cars whose tanks weren't made to handle ethanol and that it results in lower gas mileage.
"(Ethanol) is cheaper than regular gas, but a lot of people don't like it," he said.
Dadwal's claims meet opposition from ethanol supporters, who say E10-the combination of 10 percent ethanol and 90 percent regular gas, also known as "gasohol"-is fine for any type of vehicle.
The Janesville Gazette asked local ethanol experts to answer questions and rumors about E10. Here's what they had to say:
Q: Is E10 bad for my car?
A: Not unless your car was built before 1980, said Thomas Jeffries, a microbiologist with the U.S. Department of Agriculture Forest Products Laboratory in Madison.
"E10 does not harm contemporary vehicles. That's basically the bottom line," he said.
If you have an older vehicle and have never used E10 before, the ethanol might dissolve dirt in your gas tank and clog the filter, although it still won't harm the engine, Jeffries said. Ethanol also could damage the tubing in some pre-1980 vehicles.
But since 1980, and at the latest 1985, the world's carmakers have designed engines to handle up to 10 percent ethanol with no problems, Jeffries said.
The same is not true for E85, the combination of 85 percent ethanol with 15 percent regular gasoline. That fuel is only safe for specially made "flex-fuel" vehicles.
Q: Does E10 result in lower gas mileage?
A: Yes, slightly, experts said.
Ethanol has a higher octane rating than regular gas, meaning it burns more efficiently, but it also has only two-thirds the energy of regular gasoline, Jeffries said. The result is often lower mileage than regular gas.
But because E10 only uses 10 percent ethanol, the difference might not be noticeable, said Jaal Ghandhi, a mechanical engineering professor at UW-Madison.
"We've all been running 10 percent ethanol for so long that there's probably not a noticeable difference, but definitely there is a difference," he said.
Q: How do I know if a station uses E10?
A: State statutes require stations using ethanol in their gasoline to post it on their pumps.
Ghandhi wasn't sure how many stations use E10 in Wisconsin but believed it was more than half, he said. Many gas distributors like the compound because it helps meet environmental standards more easily than previous methods, he said, especially in southeastern Wisconsin where federal standards require cleaner-burning "reformulated gasoline."
A failed bill before the Wisconsin Senate last year would have required all regular gasoline to contain 10 percent ethanol. The Wisconsin Bio Industry Alliance is working on a new proposal that would offer incentives to stations using E10, Executive Director Joshua Morby said.
Q: Can I use E10 in other small engines?
A: Yes.
"E10 is safe for all your small-engine applications (such as) your car, your lawnmower, your boat," Ghandhi said.
Q: What are the benefits of E10?
A: E10 carries the same benefits as other ethanol-based fuels, though on a smaller scale, Morby said: It eases the country's dependence on foreign oil, burns cleaner than regular gasoline and benefits local farmers growing the corn used to produce it.
Ethanol also tends to be cheaper than regular gasoline and less vulnerable to volatile price swings, Morby said.
E10 also helps keep gas lines from freezing in the winter, Ghandhi said. Ethanol functions the same way as products such as Heet and other gas line antifreezes by absorbing water in the gas tank, preventing it from freezing.
