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Fuel Stickers for Plug-in Hybrids Could Mislead Drivers

The new labels will help consumers, but as designed now, they could be misleading.
August 31, 2010

Yesterday the Environmental Protection Agency released a pair of proposed fuel economy labels, which could replace the miles-per-gallon stickers now required on new cars. The stickers are needed because miles per gallon isn’t a useful measurement for vehicles that run on electricity part of the time or all of the time, and several such vehicles–electric cars and plug-in hybrids–are due to hit showrooms starting at the end of this year.

There are a lot of great things about the new labels, but they can still be improved. You can comment on the proposed labels here.

The most interesting addition is a pattern of dots that smart phones can recognize. It will link consumers to an online interactive tool that can provide personalized information about a vehicle’s performance based on estimated driving patterns and fuel costs. This tool is particularly important for plug-in hybrids, which will consume widely different amounts of fuel depending on how far drivers drive between recharging the battery. For the upcoming Chevrolet Volt, for example, drivers who plug-in every night after a commute of less than 40 miles, round trip, may never need to go to the gas station– the battery stores enough energy for such short commutes. If, however, a drivers never plugs in, the fuel economy they get may be comparable to an ordinary hybrid vehicle or a small economy car, since the car will need to rely on onboard gasoline-powered generator.

The interactive website could also allow consumers to determine the carbon dioxide emissions produced by charging their vehicles, based on the power plants in their area. In some cases, where coal is the predominant source of electricity for instance, consumers might see lower carbon dioxide emissions for hybrid vehicles than for plug-in hybrid vehicles or electric vehicles. Perhaps the EPA should consider requiring car dealers to provide Internet-enabled kiosks for consumers who don’t have smart phones, so they can easily get the same information.

There is already some controversy about one of the proposed labels–the one that would assign grades (from A+ to D) to vehicles. Some have argued against this approach, arguing that it amounts to the government making value judgments about vehicles. I don’t like it because it’s ambiguous. It’s not clear at first glance what all goes into the grade. I’d rather just use numbers to compare vehicles, particularly the number of gallons needed per hundred miles or estimated annual fuel costs, both of which are included with the new labels.

Another potential problem is that the labels can make electric vehicles look better than they really are. The labels say that the greenhouse gas emissions for electric vehicles are zero, because the EPA has decided not to count emissions at power plants. As I mentioned above, in some areas of the country, users concerned about greenhouse gas emissions could be better off choosing a hybrid–but the stickers won’t make this clear. Maybe the stickers could be changed depending on the region the car is being sold in.

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