I am in favor of alternative fuels, but I am against ethanol, especially ethanol from corn. Here is why.


Corporate Average Fuel Economy. The weighted average fuel economy of all cars sold by each manufacturer must be at least a certain minimum each year. Similar for light trucks, but at a lower standard.

Manufacturers pay penalties for not meeting CAFE.

It turns out that if a car can burn ethanol (E85), then its contribution to the manufacturer’s CAFE is bumped up. First, the CAFE formula assumes that a car is fueled 1/2 the time with gas, 1/2 with E85. Secondly, even though the fuel economy is lower with E85 (less energy in each gallon), the feds wanted to encourage E85’s use, so the actual formula is:

MPGethanol = MPGmeasured / 0.15

Yes the formula says to take the measured ethanol mileage and multiply by 7!

Then the MPGgas and MPGethanol numbers are averaged.

The Ethanol Effect

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