Japanese cars — three of them hybrids, one that runs on natural gas, and one a gasoline model — took the top five spots in the annual “greenest” vehicle ranking by an energy conservation group.
The gasoline-electric Honda Insight took the top spot in the list compiled by the American Council for an Energy Efficient Economy. The two-door was followed by Honda's natural gas version of its Civic GX, which took the top spot in 2005. Rounding out the top five were Toyota's Prius hybrid, the Honda Civic Hybrid, and the Toyota Corolla, which runs on gasoline.
Scores are based not only on fuel economy but also emissions tied to smog and global warming. Thus, while the natural gas Honda and the Toyota Corolla mileage are nearly half that of the top hybrid models, their overall score was high due to very low emissions. Natural gas, in particular, is much cleaner burning than gasoline.
The ranking also listed vehicles by category, and the ACEEE noted that U.S. automakers took the top spot there in just four of the 14 vehicle classes. “Unfortunately, the domestic manufacturers are not closing the gap with the leading foreign manufacturers on fuel economy,” Therese Langer, ACEEE’s transportation program director, said in a statement. “Detroit has had a difficult year, but given high gasoline prices and shifting consumer preferences, offering more fuel-efficient vehicles is not a luxury — it’s a business necessity.”
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