nohurry wrote:
Which brings us to the aspect of CAFE. I will admit ignorance on this (big surprise), so enlighten me. Is it true that the CAFE standard is an average of all the vehicles they build? i.e. If they build enough fuel efficient cars, and hybrids, they can get away with more on the trucks/SUV's? Or does each model have to meet certain standards? If the former, they could compensate for the trucks with enough other fuel sipping econo boxes. Or am I way off base here?
CAFE stands for Corporate Average Fuel Economy and goes off the average of what each automaker sells. It uses the "footprint"(not to be confused with carbon footprint) of a vehicle to determine what mpg that vehicle should be at per the regulation. The footprint is basically how large the vehicles is. It then takes how many of that vehicle is sold and compares it to other models that manufacturer sells and averages them out to come up with the corporate average footprint. It does the same for each vehciles fuel economy to get an average. Every manufacturers average will be different depending on the make up of what vehicles they sale.
For instance, say a manufacturer sales 125,000 trucks with a footprint of 60ft^2 that get 15 mpg, 125,000 medium sized SUVs with a foot print of 45ft^2 that get 25 mpg, and 50,000 small cars with a footprint of 30ft^2 that get 30mpg. The average footprint in this particular case is 73ft^2. Then you take the average EPA fuel economy for all vehicles sold which in this case is 32.5 mpg and compare it to the regulation chart below.
That is the basic form of it.
You can see how each manufacturers numbers may be different depending on the type of vehicles they sale and how many. A manufacture that mainly sells big vehicles will have a large average footprint numbers and a lower average mileage number to meet while a company that sales mostly small vehicles with a low footprint, but have to meet a higher average mpg.
Currently, 3/4 and 1 ton trucks were exempt from being applied to a manufacturers CAFE. That will be changing in the next few years.
Hope I explained it well enough.
