Some information on Ethanol

[Black R]

2007 Long Term Comparison by Edmunds.com
(http://www.edmunds.com/advice/altern...3/article.html)

The Final Score — Fuel Economy and Cost
After refueling we put the fuel amounts and the prices paid into a spreadsheet and compiled a clear, side-by-side comparison for both fuel consumption and cost. Remember, these results apply only to this vehicle and to the prices in effect during our 667-mile test.

Gas Result: From San Diego to Las Vegas and back, we used 36.5 gallons of regular gasoline and achieved an average fuel economy of 18.3 mpg.

Gas Cost: We spent $124.66 for gasoline for the trip. The average pump price was $3.42 per gallon.

E85 Result: From San Diego to Las Vegas and back we used 50 gallons of E85 and achieved an average fuel economy of 13.5 mpg.

E85 Cost: We spent $154.29 on E85 for the trip. The average pump price was $3.09 per gallon

Gas/E85 difference:The fuel economy of our Tahoe on E85, under these conditions, was 26.5 percent worse than it was when running on gas.

A motorist, filling up and comparing the prices of regular gas and E85, might see the price advantage of E85 (in our case 33 cents or 9.7 percent less) as a bargain. However, since fuel economy is significantly reduced, the net effect is that a person choosing to run their flex-fuel vehicle on E85 on a trip like ours will spend 22.8 percent more to drive the same distance. For us, the E85 trip was about $30 more expensive — about 22.9 cents per mile on E85 versus 18.7 cents per mile with gasoline.

The Final Score Card — Performance
We were also interested to see if there was a clear difference in performance. Here, the news was better for the renewable fuel. While the test times were generally slower for E85, the difference was small enough to go unnoticed by most drivers. Despite E85's higher octane rating (103 here) the flex-fuel nature of the Tahoe's 5.3-liter V8 engine prevents it from taking full advantage.


Environmental Comparison
E85 is often heralded as a way to reduce air pollution. Since increasing concern about global warming has focused attention on greenhouse gases, we decided to track our carbon emissions during this test.

By relating our observed fuel economy to CO2 emission figures found in the EPA's Green Vehicle Guide we determined that our gasoline round trip produced 706.5 pounds of carbon dioxide. On E85, the CO2 emissions came to 703.1 pounds. The difference came out in E85's favor, but only by a scant 0.5 percent. Call it a tie. This is certainly not the reduction in greenhouse gas emissions we had been led to expect.

Now THAT is interesting!

If I do the math for local gas prices using their approximate gallons used:
3.00 for e85 x 50gal = 150.00
4.20 for 93 gas x 36.5gal = 153.30

(Remember, there are those of us who have to use premium fuel and can take advantage of it; such as most turbo cars, high compression allmotor cars, supercharged cars, etc.)

E85 does win by a slim margin in cost and by a larger margin in octane rating. I actually expect E85 to be cheaper and cheaper compared to gasoline as a product of the war in Iraq. That remains to be seen, however.

Now if you run your daily driver on 87 octane, and it has a low static compression ratio, and it won't be able to take advantage of a higher octane fuel, then please stick to regular unleaded as there are no benefits to be had for you.

I hope not too many people start using E85, so that those of us who want it purely for a cheap and close 105 octane source can get it easily.