Consumer Reports ran a damning cover story "The Ethanol Myth" for the October issue.
- E85 is unlikely to fill more than a small percentage of U.S. energy needs.
- E85 emits less smog-causing pollutants than gasoline, but provides fewer miles per gallon, costs more, and is hard to find outside the Midwest.
- Government support for flex-fuel vehicles, which can run on E85, is indirectly causing more gasoline consumption rather than less.
- Most ethanol is being blended in a 10-percent mix to reduce smog-producing emissions and stretch fuel supplies.
Fuel economy with E85 drops about 27% compared to straight gasoline.
At an average E85 price of $2.91 per gallon in August, a 27% penalty in gas mileage means drivers would have paid about $3.99 for the same energy content of a gallon of gasoline. And E85 prices can be expected to flunctuate up and down precisely as gasoline prices fluctuate, since E85 is gasoline replacement.
Fuel economy on CR's Tahoe SUV was 7 city for E85, 9 city for gas; 15 versus 21 highway; 13 versus 18 on a 150-mile trip; and 10 versus 14 overall.
Their acceleration tests showed mostly the same results for either fuel.
Emissions parts per million were the same except for smog-forming oxides of nitrogen, which was 1 ppm for E85, versus 9 ppm for gasoline. However, E85 produces acetaldehyde, a probable carcinogen.
The manufacturers get average fuel economy credits for each FFV built, which is a very strong motivation for companies like Chrysler which build a lot of SUV's and sedans with large V8's. Therefore the credits are indirectly responsible for more gas-guzzling vehicles being built.
The government rates FFV's at about 1.66 times the fuel economy they actually get, even though the vast majority of FFV's may never be filled up with E85 at all. So a 2007 Tahoe which is rated for CAFE purposes at 21mpg will be rated at 35mpg instead. The credits are estimated to have saved Detroit automakers more than $1.6 billion in CAFE fines. Since FFV's cost automakers only about $200 more per vehicle to make them versus a gasoline version, it's a great tradeoff.