2008 Honda Civic (© American Honda Motor Co., Inc.)Click to enlarge picture

Three different Honda Civics made the "Green Vehicles" list compiled by the American Council for an Energy-Efficient Economy—the Civic GX, Civic Hybrid and standard Civic.

If you want to drive the most environmentally friendly or "greenest" vehicle, you need to think small or think hybrid. According to the American Council for an Energy-Efficient Economy (ACEEE), one third of the top 12 vehicles that rank as the greenest of 2008 feature hybrid powertrains. These vehicles combine an internal-combustion engine with an electric motor for improved fuel economy and reduced emissions.

A nonprofit organization, the ACEEE is dedicated to advancing energy efficiency as a means of protecting the environment and strengthening the economy. Each year the ACEEE publishes the Green Book, listing the Green Scores and environmental information about vehicles available in the new model year, as well as a list of the 12 "greenest" vehicles available that year.

"Hybrids stand out, even after being taken down a notch by the new fuel economy calculations," said ACEEE vehicle analyst Shruti Vaidyanathan. "And sales rose by a whopping 40 percent last year. This interest in hybrid vehicles should shine the spotlight on other green vehicle technologies that can significantly improve fuel efficiency."

View Pictures:  America's "Greenest" Vehicles

One of the mainstays of the ACEEE "Greenest Vehicles" list for the last several years — and repeating at the top of the list for the second consecutive year — is the natural-gas-powered Honda Civic GX. Scoring 57 points for 2008, the Civic GX operates on compressed natural gas (CNG). While it may not go as far on each gallon of fuel as some other entries, its combination of high efficiency and near-zero emissions makes it the highest-ranking vehicle for the environment. Note that the Civic GX is for sale to retail customers only in California and New York.

The Green Score is a numeric value of a vehicle's environmental friendliness, as assigned by the ACEEE. Determined by more factors than just fuel economy, the score also incorporates tailpipe and other emissions that can cause global warming. The higher the Green Score the more environmentally friendly the vehicle, based on the ACEEE evaluation.

There are a couple of newcomers to the Greenest list for 2008. Most notable is the smart fortwo, which was ranked fourth on the list. At just under nine feet long, the two-seat coupe or convertible is the smallest new car currently sold in America. Its 1.0-liter engine is also the smallest available, and while it lacks power, it does deliver 41 mpg on the highway.

Message Board: Are domestic vehicles being fairly judged by the ACEEE?

Another European model added to the list for 2008 is the MINI Cooper / MINI Clubman. The fun-to-drive MINI lands in the eighth position with a Green Score of 44. And unlike last year when there were no domestic cars on the list, Ford has the sole domestic offering to make the cut. The Ford Focus takes the ninth position with its 2.0-liter PZEV 4-cylinder engine.

The second, third and sixth eco-friendliest vehicles in the U.S. are all hybrids — the Toyota Prius, Honda Civic Hybrid and Nissan Altima Hybrid, respectively. The only other hybrid to make it into the ACEEE's top 12 happens to be the largest car on the list — the Camry Hybrid. Coming in tenth, this midsize hybrid earns a Green Score of 44, matching the MINI Cooper, Ford Focus, Honda Civic and Honda Fit.

Greenest Vehicles of 2008, With Green Score
Honda Civic GX57
Toyota Prius53
Honda Civic Hybrid51
Smart fortwo49
Toyota Yaris46
Nissan Altima Hybrid46
Toyota Corolla45
MINI Cooper/Clubman44
Ford Focus44
Toyota Camry Hybrid44
Honda Civic44
Honda Fit44

Source: ACEEE's Green Book: The Environmental Guide to Cars and Trucks

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