December 01, 2007

E85 and C.A.F.E. Standards

I have heard it said that the only reason the automakers make flex fueled vehicles is to satisfy their Corporate Average Fuel Economy (CAFE) standards. Well, let's look at that a little closer.

The CAFE system is run by the National Highway Traffic Safety Administration (NHTSA) and if you aren't very familiar with it, you might want to read their CAFE Overview.

Under CAFE flex fueled vehicles are given special consideration. Using an example from the overview, a flex fueled vehicle that gets 25 mpg on gasoline would be calculated to get 40 mpg. This is where the argument comes in that flex fueled vehicles are skewing CAFE numbers for the manufacturers. You can imagine all those flex fuel SUVs running around being counted against CAFE as if they were economy cars. But the CAFE rules have a maximum increase of .9 mpg attributable to flex fueled vehicles.

According to for the 2006 model year GM's domestic car fleet averaged 29.2 mpg. The CAFE standard for car fleets is 27.5 mpg. Since GM's average of 29.2 mpg is higher than the standard of 27.5 mpg by more than .9 mpg, flex fueled vehicles did nothing in 2006 to help GM reach their CAFE requirements on their domestic car fleet.

It should also be noted that flex fueled vehicles may not have increased GM's numbers by the whole .9 mpg. As far as I know there isn't any place to go to find out exactly how much flex fueled vehicles helped the overall numbers for the manufacturers. So Ford with a domestic car fleet average of 28.2 mpg or .7 mpg higher than the standard may or may not have made it without the credits from flex fueled vehicles.

Of course in 2006 GM built flex fueled cars even though they didn't need the numbers to meet the standards. And they continued to do so in 2007 and 2008. Even though they don't need to from a CAFE perspective.

So the next time that you hear that the only reason manufacturers make flex fueled vehicles is to get around CAFE requirements you will know that that is not always the case.


Anonymous said...

GM 's sudden stewardship of the environment is simply a way to continue to make gas guzzlers thanks to E85 an extremely inefficient fuel. The CAFE standards call for all car companies to achieve an average MPG for all vehicles. I believe the most recent number is 27 MPG. Well if you make the biggest money off of 10 miles per gallon SUV's you would hate to say good bye to them wouldn't you?

The CAFE standards has a loophole, that being that an E85 vehicle operating on E85 miles per gallon are ONLY figured against the actual amount of gasoline in the blend (15%) if you divide 100% fuel by 15% gasoline you get the multiplier to the mpg (666) therefore a gas guzzling 10 MPG SUV is given credit for 66.6 MPG. If you sell one SUV like this you can have 5 vehicles only achieving 20 MPG and this gas guzzling SUV and you average more than 27 MPG overall while not one of their vehicles really met the standard.

GM is not the only one taking advantage of this free ride Ford and Chrysler are too. The big three are heading down the toilet and this is just their hands clinging to the rim.

mus302 said...

Go to the NTSB website and read the CAFE Overview. The link is in the article. You have some serious misconceptions about how the program is run.

Post a Comment