New rules for calculating estimates take effect next month and will be seen on 2008 models; however, don't look for precise numbers.
Rick Popely - Chicago Tribune - Nov. 17, 2006
Since the federal government began estimating the fuel economy of new vehicles 33 years ago, it's been careful to note that actual mileage may vary.
And how, say motorists who don't get the mileage that appears on the window sticker.
The U.S. Environmental Protection Agency hopes to curb such complaints in early December when it announces new rules for calculating its estimates. They'll be rolled out beginning on 2008 model year cars.
Though the new procedures are expected to reduce the estimates from 5 percent to 25 percent, the agency's boilerplate warning will still apply: Your mileage will vary.
"We are very confident these new values will be more reflective of the real world, but how you drive is still the more important factor," said Margo Oge, director of the EPA's transportation and air quality division. "They should always be viewed as estimates. We don't want consumers to view them as absolute values."
Dave Warnke of West Bend, Wis., can attest to that. He averages 52 miles per gallon from his Toyota Prius, while his wife gets 42 from a Prius.
Warnke, however, is not complaining.
"It all depends on how you drive it, and whether you get the engine up to full operating temperature," said Warnke, an electrical engineer who was attracted by the Prius' technology more than the mileage.
His 85-mile round-trip commute to the south side of Milwaukee is mostly on freeways, where he zips along at 55 to 65 m.p.h.
His wife drives less than six miles to and from work, and Warnke thinks that's not far enough for the gas engine to get fully warm, when it operates more efficiently. His wife's Prius tops 50 m.p.g. on the freeway.
"The EPA is a set testing condition that allows some comparisons. After that, you're on your own," he said.
Under the new rules as proposed in January, the city rating for the Prius, currently 60 m.p.g., could drop to around 45 on the 2008 model. The Honda Civic Hybrid's city rating, now 49, could fall to about 38. Highway estimates for hybrids will fall roughly the same as conventional models, 5-15 percent. City estimates for conventional models are expected to decline 10-20 percent.
The final testing criteria from the EPA may not lead to changes that drastic, but the changes will be the first since 1985, when the EPA reduced city mileage estimates by 10 percent and highway estimates by 22 percent to bring them closer to what consumers said they were getting.
Some observers say an overhaul of the EPA estimates is long overdue. Auto and travel organization AAA and Consumer Reports magazine, for example, conduct their own fuel-economy tests and find the current ratings wanting.
The Automobile Club of Southern California, a branch of AAA that operates a test facility, measured on-road mileage in 41 vehicles last year and found that 36 experienced worse mileage than the EPA estimates--on average, 4 m.p.g. less.
AAA then measured mileage the way the EPA does, running city and highway driving simulations in a laboratory. But AAA included three EPA emissions tests that reflect more aggressive acceleration, running the air conditioner and starting a cold engine in sub-freezing temperatures, all of which hurt mileage.
The results came within 1 m.p.g. of the mileage AAA actually recorded.
"With the old test, it was almost impossible to get the EPA ratings," said Steve Mazor, manager of AAA's auto research center in Diamond Bar, Calif. "The [new] test is more accurate and a much better predictor of the mileage people will get."
The EPA will incorporate the AAA tests and add other factors in coming up with the new fuel economy estimates.
"It reflects the way people drive today," Mazor said of the more demanding regimen.
Consumer Reports, which measures mileage on a test track and public roads, said that of 303 vehicles it has tested over six years, only 29 equaled or exceeded the EPA estimates. In city driving, vehicles it tested typically get much less than the EPA numbers.
"The EPA city cycle is fairly gentle, much more gentle compared to how most people drive today," said David Champion, automotive testing director for Consumer Reports. "City driving today has more aggressive acceleration and more braking than the EPA test."
In addition, because the tests are conducted indoors under controlled conditions, automakers can optimize the vehicles to perform well in the EPA's driving cycles, Champion said. That is especially true with hybrids, which may run primarily on battery power in the EPA test but use the gas engine more in the real world.
According to the EPA estimates, hybrids get better mileage in the city because that is where they use electric power. However, most hybrids tested by Consumer Reports and AAA didn't come close to those estimates, either.
Consumer Reports got 35 m.p.g. in the city with a Prius rated at 60 and 50 on the highway (versus the EPA's 51). AAA tested six Prius models, and their mileage ranged from 37 to 50 in combined city and highway driving.
Consumer Reports got only 26 m.p.g. in city driving from a 2003 Honda Civic Hybrid rated at 48 by the EPA. AAA tested two 2004 Civic Hybrids, and one got 36 and the other 49 overall.
"Hybrids still get better mileage than other vehicles," AAA's Mazor said. "It's just not as good as people expect."
Toyota and Honda, the two largest sellers of hybrid models, say they don't expect the lower fuel economy ratings to hurt sales.
Toyota spokeswoman Ming-Jou Chen said consumers buy the Prius for its technology, low emissions and styling. "With a Prius, people know you're driving a hybrid and that it is part of an image that you're environmentally conscious."
Besides, John German, Honda's manager of environmental and energy analyses, said: "Hybrids will drop a little more, but all the vehicles will come down. The relative impact stays the same. We have no problem with that."
Honda, however, worries that the new procedures will overemphasize aggressive driving and extreme conditions, such as the one that runs the air conditioner in 95-degree heat after the car has sat in the sun for 10 minutes. The EPA has not said how much weight it will give those factors.