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But the problem is that ethanol has less energy per unit/volume than gasoline, so given equally efficient driving modes for each fuel gasoline will beat ethanol every time in a flex fuel vehicle.

Ethanol: 23.5 megajoules/liter
Gasoline: 34.8 megajoules/liter

E-85 can actually run from 70% to 85% ethanol depending on the region of the country, so its energy content is variable.

I actually have a flex fuel vehicle and have used E-85 at times, so....
 

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But the problem is that ethanol has less energy per unit/volume than gasoline, so given equally efficient driving modes for each fuel gasoline will beat ethanol every time in a flex fuel vehicle.

Ethanol: 23.5 megajoules/liter
Gasoline: 34.8 megajoules/liter

E-85 can actually run from 70% to 85% ethanol depending on the region of the country, so its energy content is variable.

I actually have a flex fuel vehicle and have used E-85 at times, so....
The fact is even though ethanol does have more energy, that because ethanol has higher octane the engine can have higher compression and the timing can be altered to where there is very little drop in mileage. The fact is though that ICE engines are tuned to gasoline so the you will continue to see a 30% drop in ethanol powered cars.

An engine designed to run on ethanol when ran on gasoline would ping like crazy, have lower horsepower and probably wouldn't last very long.
 

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Discussion Starter #8
I think

overall if the gas miliage for the volt is 150 miles then on ethanol (which is 70% of that)it would be about a hundred. also I think that overall you'd be useing less gas overall because you'd be using a renewable resourse. so you'd probably import less oil. and 90 to 100mpg isn't all that bad. better than most anything that's out there now.
 

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Plj

The 150 MPG figure comes from calculating a 60 mile trip, where the first 40 miles are on stored battery power (and therefore no gasoline is used) and the last 20 miles are with the backup engine running to charge the batteries while you still drive, which is targeted to get the equivilent of 50 MPG. So you would use two-fifths of a gallon total during this hypothetical 60 mile trip and therefore get 150 MPG. 60/150 = 2/5.

It is important to understand that this figure changes depending on the length of the trip. The farther your trip exceeds the 40 mile battery range, the less calculated MPG you get, but in no case would it be less than 50 MPG, even if you never charged the car from an outlet. But if you travel LESS than 40 miles between charges you get infinite MPG, since you use no gas at all.

This is one of the beauties of this car, since you never need to worry about the batteries being charged if you're away from an outlet. It is all automatic and your MPG will always be anywhere from 50 MPG to Infinite MPG.

Let's say you normally use the car just to commute, and one day on a whim you decide to drive to Las Vegas after work. You're good to go no matter where you live! Just add gas as needed.

Most people using this car for commuting will get Infinite MPG, assuming they charge it each night at home.

Hope this helps.

PLJ
 

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Consumer reports tested an E85 Tahoe last year and determined that the fuel economy using E85 is much lower even with a GM FlexFuel E85 engine. They concluded:

-There's a 27% drop in fuel economy using E85 compared to E10 (regular gas).
-The poor fuel economy outweighs any cost benefits of E85 (paying $2.91/gal for E85 is like paying $3.99/gal for regular gas).
-A 440 mile tank (gasoline) only gets you 300 miles with E85.
 

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I have read somewhere that if the ICE is designed specifically with proper compression ratio and the timing of the spark for the ethanol, then the efficiency approaches that of gasoline fuel.
You can't do that until E85 is available. Kind of like looking for a place to refuel you hydrogen fool cell car.
 

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You can't do that until E85 is available. Kind of like looking for a place to refuel you hydrogen fool cell car.
There are many ARCO stations in California that are NOW offering E85. In our city, the E85 has been offered for more than 5 years now. One of the engineering studies performed on the compression and ignition adjustments was sponsored in part by NREL.

And don't forget Brazil that have already adjusted their compression and ignition. They are prime producers of alcohol.
 

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And prime destroyers of rainforest. They burn down the rainforest to plant their ethanol crops.
Not only for ethanol though, because they are growing other crops and mining the rainforests aside from ethanol. But this is going slightly out of context. We are talking about optimizing the power from ethanol for a well configured ICE, and not about political rants.
 
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