Achieving such a standard in 12 years seems ambitious given that this is roughly double the average MPG of 2011, but this is what new regulations put forth by the US EPA and Department of Transportation are aiming for. The true average fuel economy will be around 40 MPG because auto manufacturers can earn credits by selling alternative fuel vehicles and the standards only apply to cars, not trucks.
Read about it here at CBS News and here from the NHTSA.
Excellent source of basics on CAFE standards FAQ here from Edmunds.
Massive detail and analysis here from US EPA.
The guys at Freakonomics have a nice description of why standards such as these are often less desirable than taxes. This is a topic that we're going to spend a lot of time with this semester.
CAFE Standards (Corporate Average Fuel Economy) originated in 1975 in response to the 1973 OPEC oil embargo. Here is a brief history of CAFE standards from PEW.
Here are some basics on CAFE standards from NPR.
Here is a consideration of unintended consequences of more fuel efficient vehicles.
Like most issues that we'll discuss in class, this one is controversial.
Some argue that the new, higher standards will create jobs (full report here).
Other argue that higher standards will cost jobs.