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Alertnative Fuel - Ethanol 85 Myth

Test results: E85 vs. gasoline
This chart shows how our 2007 Chevrolet Tahoe performed while running on E85 and gasoline in three fuel-economy tests and overall, in four acceleration tests, and in three emissions tests for gasoline vehicles.

 

E85

GASOLINE*

Fuel economy, mpg

City

7

9

Highway

15

21

150-mile trip

13

18

Overall

10

14

Acceleration

0-30 mph, sec.

3.4

3.5

0-60 mph, sec.

8.9

9.1

45-65 mph, sec.

5.7

5.8

Quarter-mile, sec./mph

16.8/84.6

16.9/84.5

Emissions, parts per million

Nitrogen oxide

1

9

Hydrocarbons

1

1

Carbon monoxide

0

0

We put the Tahoe through our full series of fuel-economy and acceleration tests while running on each fuel (see our test results). When running on E85 there was no significant change in acceleration. Fuel economy, however, dropped across the board. In highway driving, gas mileage decreased from 21 to 15 mpg; in city driving, it dropped from 9 to 7 mpg.

You could expect a similar decrease in gas mileage in any current FFV. That's because ethanol has a lower energy content than gasoline: 75,670 British thermal units per gallon instead of 115,400, according to the National Highway Traffic Safety Administration. So you have to burn more fuel to generate the same amount of energy. In addition, FFV engines are designed to run more efficiently on gasoline. E85 fuel economy could approach that of gasoline if manufacturers optimized engines for that fuel.

For complete detail go to Consumer Reports