As alternative fuel vehicles start to hit the market, regulatory agencies are being faced with a growing new dilemma --
how to accurately measure fuel economy. According to EPA test guidelines, the urban test cycle is 11 miles long, while the highway is 10.3 --
the Volt can supposedly drive 40mi before its gas engine kicks in. That's prompted some, like the
NY Times, to speculate that the GM Volt might actually be able get the coveted triple-digit EPA mileage rating.
The folks at the EPA are kicking around a bunch of
new methods to test the Volt, but exactly how can they change the test criteria for one vehicle, and yet claim to have a standardized procedure? One method includes running the Volt until the 1.4L generator engine kicks in. Then, they'll run the cycles again with the vehicle in charge mode.
The truth is, with the introduction hybrids, range extended EVs, and even tiny
pod cars, the classic "MPG" standard for rating efficiency is starting to lose its relevance. Manufacturers like VW have already voiced a very
public challenge to the EPA rating of their
Jetta TDI. Rather than list the Tesla Roadster's efficiency in miles, the EPA lists it in kW hours.