Don’t Believe All the Hybrid Mileage Ratings
By KATE BERRY
Staff Reporter
How good is the gas mileage for Toyota’s hot-selling Prius or the Honda Civic hybrid?
Not as good as advertised, it turns out.
Some consumers are averaging far lower gas mileage for new hybrid cars than the government-approved fuel economy ratings on the actual labels.
Toyota Motor Sales U.S.A. and American Honda Motor Co., both headquartered in Torrance, have acknowledged the discrepancies. They blame the 10 to 20 miles per gallon difference squarely on the shoulders of drivers and variable road conditions.
“There are a number of factors that could cause the fuel economy to be lower,” said Dave Hermance, Toyota’s executive engineer for environmental engineering. “We’re trying hard to improve not only the tests but the end-use vehicle economy.”
Consumer Reports magazine reported last month that gas mileage for the Toyota Prius and Honda Civic hybrids are 20 percent to 25 percent lower on actual road tests than on the EPA-approved labels.
As a result, the EPA is requesting additional comments from consumers and new data from hybrid manufacturers to determine what factors are skewing the ratings.
The EPA rated the 2004 Prius at 55 miles per gallon for combined city and highway driving, and the Civic hybrid at 47.5 mpg. In actual road tests, Consumer Reports found the Prius gets 44 mpg and the Honda hybrid 36 mpg. Both cars performed much better on the highway than in city driving.
All vehicles sold in the U.S. are required to have a label posted on the window sticker that contains city and highway miles-per-gallon. To calculate those figures, car makers perform tests at their own facilities. The EPA audits the manufacturers’ data to confirm the results.
Nevertheless, the EPA claims it adjusts its miles-per-gallon estimates to reflect real-world driving conditions for the average motorist.
Juan Avila, a spokesman for Honda, called the EPA’s testing guidelines “antiquated,” and said the numbers are off for all cars, even though hybrids are getting most of the attention.
(Of course, auto makers would lobby fiercely against changing the EPA’s methods for arriving at fuel-consumption figures if the miles-per-gallon minimums weren’t lowered as well.)
“It’s a huge misconception that this applies only to hybrids,” Avila said. “We feel it’s a non-issue that affects all cars and to make a separate point about hybrids alone is unfair.”
Both Toyota and Honda claim several factors can result in cars getting lower gas mileage, including accelerating too quickly (although hybrids may be an exception), braking hard, driving at excessive speeds and using air conditioning or heating units.
Other factors include keeping car tires inflated at the appropriate pressure, using the proper grade motor oil, replacing clogged air filters, and properly tuning an engine.
Even with their lower real-world results, hybrids get better gas mileage than the average new car.
For 2003 model cars and trucks, the average fuel economy is 20.8 miles per gallon, according to the EPA’s annual gas mileage statistics, down from 21 miles per gallon last year and 6 percent below the peak for passenger vehicle efficiency of 22.1 miles per gallon set 15 years ago. Not surprisingly, SUVs, vans and pickup trucks averaged just 17.6 miles per gallon.
Hybrid vehicles have quirks of their own.
Because the Prius switches between battery power at low speeds and a gasoline-powered engine at higher speeds, accelerating quickly between the two power sources can help save fuel. (The Civic and Insight use a system that employs a gasoline engine as the main power plant, with an assist from the electric motor during acceleration.)
Toyota may rethink the automated display on the Prius dash board that shows the vehicle’s fuel economy fluctuate as the car is driven, which makes consumers hyper-aware of what they’re not getting.
“It’s a constant reminder and sometimes they’re getting less than what the EPA label says,” Hernance said.
Not So High? – EPA miles-per-gallon ratings for hybrid vehicles.
Vehicle, City, Highway
Ford Escape Hybrid, 35-50*, N/A
Honda Civic Hybrid, 48, 47
Honda Insight, 57, 56
Toyota Prius, 60, 51
*Ford company estimate; EPA ratings are not yet published.
Source: Environmental Protection Agency
