An annual ranking of the "greenest" and "meanest" cars sold in the United States found that no American vehicles got the best grades -- those all went to Japanese carmakers. The worst score, meanwhile, went to a newcomer on the list: the diesel version of VW's Touareg SUV.
Released Tuesday, the report by the American Council for an Energy-Efficient Economy ranked 2004 model cars on emissions and fuel economy. An overall "green score" also factored in the health impacts of pollutants as well as the level of so-called greenhouse gases like carbon dioxide that many scientists fear are fueling global warming.
Topping the "greenest" list was the Honda Civic GX sedan, which runs on compressed natural gas -- not a choice that's practical for most buyers but one that's much cleaner than gasoline.
The rest of the list, however, is consumer friendly: The gas-electric hybrids by Honda and Toyota take the next top spots, followed by versions of these gasoline models: Toyota Echo, Nissan Sentra, Honda Civic HX, Mazda 3, Toyota Corolla, Hyundai Elantra, Scion xA and Honda Civic.
Detroit short on fuel economy
The energy watchdog criticized American automakers for failing to make the "greenest" list.
"The absence of the Big Three ... is disappointing," Therese Langer, ACEEE's transportation program director, said in a statement that accompanied the list. "But the fact is that the greenest vehicles today excel in both fuel economy and tailpipe emissions, and Detroit has yet to do that."
Detroit has kept up with Japan in reducing tailpipe emissions, ACEEE said, but Japanese carmakers "are still taking the lead on fuel economy."
American, Japanese and European carmakers did have more in common when it came to the "meanest" vehicles listed. DaimlerChrysler, Ford and GM joined Toyota as well as Lamborghini, Land Rover and Volkswagen on that list.
Many modern diesel engines do get up to 40 percent better mileage than their gasoline peers, ACEEE noted, but they can also emit much more nitrogen oxide -- a pollutant that combines with heat to form smog.
Sales pitch for buying green
ACEEE's list is part of an online consumer guide that also ranks vehicles by class. Among larger vehicles, the Dodge Caravan minivan, Toyota Tundra pickup, and Nissan Murano SUV scored well.
Passenger cars like Chevrolet's Impala and Ford's Focus Wagon also scored well in their respective classes.
But ACEEE also noted that a vehicle's environmental impact varied as much as four-fold within a given class, and five-fold across all 2004 vehicles.
Bill Prindle, the ACEEE's policy director, said that buying the greenest vehicle in a given category is good for individual buyers, local communities and the nation.
"It's the choices we make in buying cars and trucks that determine how clean the air is, and how dependent we are on Middle East oil," Prindle said in the statement. "If new car and light truck buyers chose the most efficient vehicles in each size class, we would slash the 2004 fleet's gasoline use by 18 percent, reducing gasoline purchases by $3.2 billion and saving the average buyer $195 a year. And, of course, we would also cut greenhouse gas emissions."
Background on ACEEE and its online consumer guide is at greenercars.com.
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