Editorial: EPA fuel economy proposal requiring road tests is pointless

Earlier this week, the EPA announced a new proposal that would require all car manufacturers use real-world data for its fuel economy calculations. On the surface, this seems like a reasonable proposal and stems from a recent number of cases where automakers are being sued for overstating their fuel economy figures in the pursuit of evermore sales. However, if we take a serious look at the way fuel economy testing is done now, we quickly see that this new proposal is little more than a bit of chest thumping by the EPA and will have little genuine impact on the complaints that consumers have about automakers and the fuel economy numbers on the Monroney sticker.

Currently, fuel economy tests are performed using dynamometers, essentially large calibrated drums, that simulate the loading and friction of the road on a cars wheels. Professional drivers are used to perform a series of standardized tests that are designed to simulate various driving situations that a typical driver might encounter. That data is recorded and the final fuel economy ratings are calculated from this data.

However, what the EPA does not clarify to us is that these tests are often conducted by the manufacturers and only submitted to the EPA for verification. Additionally, it is a little known fact that not all cars are required to be tested. In fact, the EPA allows vehicle models with identical drivetrains (engine and transmission combinations) to have fuel economy figures that are calculated off of the test of just one model. That means if the Ford Fusion Hybrid and the Ford C-MAX share a drivetrain (which they do), Ford only needs to test the Fusion and can then use those numbers to calculate the data for the C-MAX (which they did). This has resulted in some rather gross overstatements of fuel economy performance as a result.

Image courtesy of Car and Driver.

So this most recent proposal that requires automakers to gather air-resistance and other conversion data from actual cars driving on a test track, rather than just from their computer models, does little to address the actual problem with how fuel economy ratings are determined. For one, the fact that the EPA does not independently test all of the cars itself leaves plenty of room for an automaker to simply fudge the data that it submits. Add to that the fact that automakers are not actually required to test all of its cars and can instead just calculate the fuel economy and you start to see where the whole system begins to fall apart.

Rather than this pointless proposal, the EPA should instead look to either better educate the buying public about the nature of the fuel economy numbers that are published on the window sticker of new cars or they should set up regulatory requirements that enforce independent monitoring of all fuel economy tests conducted by automakers and require that automakers test all cars.

Educating the consumers by arming them with an appropriate frame of reference for how those fuel economy numbers are calculated allows consumers to make more informed decisions. This places more burden on the consumer to be conscientious about their selections, but also reinforces that the information provided on the Monroney sticker is to serve as a reference, not to be a guarantee. Of course, there is always the possibility that this will fall on deaf ears, as much consumer advice frequently does.

Requiring independent monitoring of all automaker fuel economy testing procedures will help ensure that the automakers do not game the system through means such as using ultra-efficient model variants to set the data in the computer models. This also will put in place an independent observer that can suggest incremental changes to fuel economy testing procedures over time to improve their effectiveness and accuracy. And by increasing the requirement to test all cars, rather than allow automakers to rely on computer models, the numbers should be increasingly closer to actual performance.

As fuel economy continues to become an increasingly important factor in consumer's car buying decisions, having good points of reference are going to be increasingly critical to helping people make the right choice. Asking automakers to add real-world reference points to their data models is an improvement, but is quite literally about the absolute least that the EPA could do. Rather than making this relatively pointless change, the EPA really needs to throw its weight, along with the weight of the government, behind some changes that will have some real impact rather than wasting valuable political capital asking for the equivalent of rearranging the deck chairs on the Titanic.