EPA's new system for measuring fuel efficiency should bring cars’ advertised MPG closer to their actual gas mileage. At present, fuel efficiency testing is not done under real world driving conditions, so the sticker numbers represent inflated fuel mileage.
Interestingly, hybrids will probably see the largest decline in their MPG sticker numbers, as the new tests, slated to roll out in 2008, incorporate more cold-weather driving and quick acceleration—neither of which make efficient use of a hybrid’s electric capabilities.
Toyota, manufacturer of the top-selling Prius, is in favor of the new rating system:
"This is all about providing more and better information to consumers. [It] doesn't change the car or the technology, just the way the mileage is calculated," said Ming-Jou Chen, spokeswoman for Toyota Motor Sales USA. "It makes the estimate closer to real-world numbers, and we fully support that."
The 2008 tests will include, for the first time, medium-duty trucks and large SUVs, previously exempt from testing because of their “commercial” status. Perhaps consumers, finally provided with more accurate mileage estimates, will be discouraged from buying behemoths with insultingly low gas mileage.
Vehicle mileage estimates get real. LA Times. 12 Dec 06
Real MPG: An Environmental Working Group report on corporate MPG requirements. July 06
