The difference between expectations and reality can be brutal. Just ask anyone with a hybrid car. Enticed by impressive mileage estimates, drivers pony up thousands of dollars extra, only to find that their on-road miles per gallon never live up to the sticker's promise. Conventional-car owners, too, have long complained about the discrepancy between the estimate of fuel economy and the reality of gas consumption, but the gap is an especially bitter pill for anyone who has spent a year on a waiting list.
Now the Environmental Protection Agency is coming clean about what "miles per gallon" really means-and mpg averages for both conventional and hybrid vehicles are set to nosedive. In January the agency, under mounting pressure from consumers and environmentalists, finally agreed to upgrade its 20-year-old testing system to determine mileage ratings for cars and trucks. The plan is to implement three new tests that will be more accurate and "better reflect the way most people drive," says EPA spokesperson John Millett. The new regulations will be fully phased in by fall 2007, when 2008 models debut.
The proposed changes would bring several additional elements into the testing lab: cold-weather conditions; higher speeds and more rapid acceleration; and the use of air-conditioning. Most experts agree that the tests will provide more accurate estimates that better reflect modern engines and driving conditions. Compared with 1985, when the EPA last revised its testing methods, today's vehicles are more powerful, speed limits are higher, there's more stop-and-go traffic, and A/C comes standard.
But some experts worry that the EPA tests will disproportionately penalize high-mileage vehicles with small engines, such as gas-electric hybrids. The Prius and its kin use a battery as a second source of onboard power, which doesn´t produce as much energy in cold weather. The engine consumes more gas to make up the difference. And because of their smaller engines, hybrids are also more sensitive to A/C use. As a result, a gas guzzler's number could dip from 20 mpg to 18, and a hybrid's city estimate of 60 mpg could plunge to 42.
"We're concerned that sales will drop too," says John German, formerly with the EPA and now a hybrid-vehicle expert at Honda. That, he says, would be an unfortunate outcome, since hybrids will still get better gas mileage than nearly every gas-powered vehicle currently on the market.
The other worrisome issue, industry experts say, is that the new EPA tests will do nothing to improve overall fuel economy in the U.S. That's because the Department of Transportation has its own set of calculations to regulate fuel-efficiency standards, known as the Corporate Average Fuel Economy rules, for automakers. Under the CAFE rules, the mandated average fuel economy for passenger cars is just 27.5 miles per gallon. Increasing that standard is the only way to force manufacturers to devise new fuel-efficient technologies, says Brendan Bell, clean-vehicle spokesperson for the Sierra Club. Bell puts the new EPA changes this way: "It's like the doctor can now give a more accurate diagnosis, but you're still not getting a prescription for the disease."
The EPA has long used tremendously inaccurate protocols to determine miles per gallon consumption.
They do not measure consumption of the fuel. They neither measure the quantity of the exhaust nor the the weight. All they measure is the percentage values of related emissions and add an algorithm to calculate consumption.
After going through two rounds of EPA FTP testing on The Gadgetman Groove, I can tell you that they will never be accurate. That is, until they begin to incorporate actual volumetric measurements, rather than ration of pollutants taken from sampling the exhaust that is produced.
In modern, computer controlled fuel delivery systems, there is one component that has not been taken into account. The Oxygen sensor is the primary reference point for the computer to meter the fuel delivery. In reading the RATIO of oxygen to hydrocarbons, the computer responds to keep the RATIO correct.
So long as there is an Oxygen Sensor and a computer in charge and the EPA refuses to measure either actual consumption by mass rather than reading the RATIOS, all they can EVER do is produce theoretical mileage.
Sorry, guys. The most trusted authority has been bogus since the advent of the computer-controlled fuel delivery systems.
In both rounds of testing, the vehicles in the field showed 40% and 60% increases in MPG's, yet the EPA would have you think they showed a 5% DECREASE. The USPS delivery vehicles get a max of 12 MPG's, but in the lab, they get 19.
Does someone have an explanation for this? Then share it with me at www.GadgetmanGroove.com and I'll adjust my opinion.
Until then, I will continue to be disappointed in this governmental agency as unworthy to lead, let alone to trust.