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What the EPA’s New Window Stickers Get Right

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How many miles will an electric car go on a gallon of gasoline? This is not a trick question. Federal law requires all new cars sold in the U.S. to feature a window sticker that lists fuel efficiency as measured in miles per gallon. Electric cars—which, of course, use no gasoline—are not exempt.

This was the dilemma faced by the Environmental Protection Agency as it redesigned the window sticker. The new designs calculate the efficiency of electric and plug-in hybrid vehicles according to a figure called miles per gallon equivalent—a rough estimation of how much energy the vehicles consume. The EPA stickers feature a flood of new information, including ratings of greenhouse gas and smog emissions.

Still, many environmentalists howled at the choice of sticker design. The New York Times quoted Dan Becker, director of the Safe Climate Campaign, as saying that "the Obama administration has dashed consumers’ hopes for clear information to make educated choices about which cars are really clean." He was referring to an alternate sticker design—one not chosen by the EPA—that was dominated by a single letter grade. In this system, electric vehicles would get an A+, while the worst gas guzzlers would be saddled with a D (if it’s approved for use on the road, it’s not a failure, the thinking goes).

The problem with this system is that it blurs the distinction between similar vehicles. Want a mid-size sedan? Under the letter-grade system you’d be choosing between cars that get a B- and cars that get a B. (As we noted last year, 88 percent of all new vehicles would score somewhere between a B and a C.) In effect, the letter-grade system would tell consumers that electric vehicles are better than plug-in hybrids, which are better than regular hybrids, and so on down to the Ferrari/Suburban pit of pollution. This, the EPA wisely decided, is of little use to the average car-buyer.

Even though the new stickers are cluttered with numbers, they end up giving consumers a clearer idea of the true costs of ownership. The traditional miles-per-gallon metric is deeply flawed, as it doesn’t provide easily scalable view of the differences in gasoline consumption among vehicles. For example: The two miles per gallon separation between SUVs getting 16 mpg and 18 mpg will lead to a larger difference in total gasoline consumed than the 15 miles per gallon spread between 40 mpg and 55 mpg vehicles.

The EPA accounts for this with a neat metric in bold, just to the right of the standard mpg figures: The total cost of gasoline, summed over five years. More than anything else, this is what the typical U.S. consumer wants to know—how much gas am I going to have to buy? By this metric, electric and plug-in hybrids look darn cheap. Environmentalists should be cheering.

Image: The new window sticker for a plug-in hybrid electric vehicle, courtesy of the Environmental Protection Agency


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  1. 1. rshoff 2:05 pm 05/26/2011

    What’s in a sticker. Don’t we research large purchases, such as cars, before shopping? It’s not possible to put all that information on one window sticker. Can you even create a viable metric that can communicate costs, efficiency, gas usage, electric usage, etc, etc, etc. And how about cost of maintenance and pollution quotient of those batteries? Pollution from manufacturing? Economic costs? Pollution as a result of those economic costs (shipping from overseas?) You see, this information was never really available. We always that the MPG defined it all. It didn’t. Now that we are more conscious of all of these considerations, we can see the gaping holes.

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  2. 2. sault 3:19 pm 05/26/2011

    This new sticker is about as good as anybody could have hoped. I don’t know where you find the "maintenance and pollution quotient" for electric car batteries. I know that the Leaf’s battery is warrantied for 8 years / 100,000 miles, so the customer will not be liable for any maintenance issues that come up during that time. Nissan seems very confident that they will have few, if any, headaches taking care of Leaf battery packs in offering such a substantial warranty. As far as the "pollution quotient" goes, the electric utilities are VERY interested in these battery packs for grid stablization once they aren’t useful for road duty anymore and a recycling infrastructure will be in place once the battery packs finally give out.

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  3. 3. rshoff 3:39 pm 05/26/2011

    No argument here, these stickers are good enough as far as I’m concerned. My point was simply that it wouldn’t be possible to put all the pertinent information about cost and pollution into one sticker anyway. I wasn’t bashing any technologies. Merely stating that being more knowledgeable we are finding that the old mpg information didn’t even provide a complete picture.

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  4. 4. ssarryo 11:14 pm 05/26/2011

    I think that the "quotient" information that you are mentioning should be included in the owner’s manual. What would be even better is if an owner’s manual would be in digital format to make the information greener.

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  5. 5. electric38 1:18 am 05/27/2011

    When the move to solar rooftops occurs, these stickers will indeed be confusing. Energy from the sun powering the rechargable batteries could drive the MPG to an infinite number. Depends on where the person driving lives. Those in the sun belt may very well be able to eliminate their electric bill, drive their vehicles and sell back a little of the excess power to the local utility.
    Keep an eye on what Germany does as they have already built a powerful solar infrastructure (using aggressive F.I.T’s), virtually eliminated nuclear and have recently agreed to sink billions into their electric car marketing. Their engineering has been technologically in step with a clean future that benefits many citizens. Japan will likely do something sililar.
    It will be exciting to see the design of many of the solar charging carports (should be coming out with some real architectural masterpieces) and they are nowhere near a sunbelt. Mass production using round the clock 24/7 robotics will likely speed along the distribution of these vehicles.
    These new stickers need to allow credit for solar driven MPG.

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  6. 6. badenewby 1:45 am 01/28/2014

    Bade Newby showcases wonderful self sticker and window stickers in UK. Our custom sticker are printed on quality white vinyl with guarantee of more than 3 years. Visit our site today to know more about our organizations or call us at 01509 412 228.

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  7. 7. Adamsire 7:31 pm 02/17/2015

    this something astonishing to me.. as of now i was also aware only with window stickers printing but this something new to my knowledge we should concentrate on that as well. Thanks for this information.

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