Fuel Economy Figures

For decades, the new car buyers have complained that their fuel economy has not been up to EPA estimates on the window sticker. Since the EPA has begun to provide estimates of mileage in the 1970s, it is known that the testing methods were not reflective of the reality of driving conditions and are more effective in comparing the mileage between the different models for determining the actual fuel economy.

Although changes have been made to estimate the fuel economy system several times since the 70s, new tests and the formula for determining the mileage, and new window stickers, will be phased in for model year 2008, and new test procedures will be mandatory by 2011.

It is speculated that the mileage shown on window stickers will be reduced in most models, but these figures more closely match the real world mileage of the vehicle. For drivers good driving habits and maintenance, they may be able to get the fuel economy that is higher than expected.

The current tests for fuel consumption are conducted on vehicles on a treadmill-type device designed to simulate real driving. However, these tests are performed at moderate temperatures, without any accessories running, such as air conditioning. The road test is far exceeded, with the top speed is only 60 mph and an average speed of 48 mph. The city driving test simulates driving 7.5 miles to an average of 20 mph with 18 stops.

New procedures fuel economy test will take into account and to reproduce the three common scenarios that can fuel economy significantly lower, such as hard acceleration, the low temperature operation, and use of conditioning. Although some of these tests are currently carried out, they are used to determine the emission data, but data are taken into account in estimating mileage. For the 2008 model year, the EPA is simply using a different formula to try to make more accurate estimates mileage.

It is expected that the new estimation formula and new test procedures will lower fuel consumption ratings of 10-30% across the board. Vehicles with mileage ratings will see the largest reductions are likely to be those who are affected by strong demand on the engine hard acceleration, air conditioning, and cold temperatures, such as high-mileage cars.

Many environmentalists are disappointed that the hybrids are expected to be among the vehicles with the largest decrease in estimated mileage. Some say it may have a negative impact on the market for hybrids, but each vehicle will have the same fuel economy real. The only difference is a more realistic mileage.

While some fear that this will cause consumers to overlook the hybrid cars, many analysts and industry insiders see the new formula and tests in a positive light. Dave Alexander, principal analyst at ABI Research, said: "There is a long-term potential for better customer satisfaction." This is because a car with the window sticker says 30 mpg will be able to produce the mileage to 70 mph with the air conditioning on, in real driving conditions, instead of a top speed of 60 mph without accessories in a climate controlled setting.

Instead of turning off consumers of hybrids, more accurate mileage estimates may allow consumers to buy vehicles that are actually more fuel efficient rather than continue to be dissatisfied with lower mileage than expected.