Maybe the federal government should adopt Consumer Reports as a model for fuel economy testing. Or just outsource the task to the magazine.
The EPA seems to be feeling the heat over its miles-per-gallon ratings, which adorn new-car window stickers.
As just about anyone who has checked their fuel economy can attest, EPA numbers are at best rough indicators of actual performance. Consumer frustration apparently has led the EPA to consider adding real-world testing to its regimen.
There are two problems with current EPA testing. First, the EPA requires automakers to test vehicles in a laboratory using a dynamometer on an extremely precise cycle. (You can check out test procedures at fueleconomy.gov/feg/fe_test_schedules.shtml.)
Because the tests are standardized, each automaker can verify (or not) a competitor’s rating. The EPA also spot-checks some vehicles each year.
That may suffice for the EPA’s regulatory mission, but the test cycle wasn’t set up to give consumers realistic fuel economy advice, and it doesn’t.
Then there’s problem No. 2: Predicting consumer fuel economy is basically impossible anyway.
The discrepancy between running a dyno test and driving on a traffic-filled street is a problem. But at the consumer level, variations in driving styles and the conditions create near-infinite variations. Essentially, there’s no “real” number.
Would real-world testing get the EPA closer to reality? Maybe.
But the EPA would run up against the variables that it has tried to avoid with laboratory testing -- driving style, terrain, wind, wet pavement and so on.
Even with tight specs on real-world testing, automakers would test vehicles with different drivers and with some level of variation in routes and conditions. It would be difficult to get verifiable, apples-to-apples results. There would also be the possibility of automakers taking advantage of the variations to get the best possible results.
That’s why the feds should take a cue from Consumer Reports, which does its own testing. The EPA should consider testing cars itself on its own test track with its own drivers.
It would be an added expense, to be sure. But it might be as close as the EPA can come to getting credible miles-per-gallon numbers.