The Honda Civic Natural Gas is the only car commercially available today powered by the clean petroleum substitute. It’s a version of the standard Civic sedan, with a large cylindrical natural gas tank squeezed into the trunk. Burning natural gas produces such negligible emissions that natural-gas cars are eligible for California’s advanced technology partial-zero-emissions vehicle program, and so are eligible to use carpool lanes without passengers. It also contributes to reducing reliance on foreign oil.
We found the CNG powertrain brings a few compromises when we tested the previous-generation car. Since we tested the 2008 Civic GX, the Civic line has been redesigned, dropping in overall test scores along the way. What hasn’t changed significantly is that depending on where you live, natural-gas refueling stations can be few and far between. There are only five in Connecticut, although some other states have many more. Currently, there are about 1,000 CNG stations nationwide, compared with almost 200,000 gasoline stations. (Check to find refueling stations in your area.)
The Civic Natural Gas sedan’s fuel tank also occupies more than half the trunk, and once filled, it holds the energy of just eight gallons of gasoline. Honda rates the car's cruising range at 220 to 250 miles.
That might be optimistic. In our experience of the previous version of the natural-gas Civic (then called the Civic GX), we found the low-fuel light came on after only 150 miles of driving. That warning indicates just 30 miles left, which provides little leeway to look for a fill-up location given their scarcity in our area. We found that car got the equivalent of 32 mpg, which is very good. Honda claims the new version is about 10-percent more efficient, giving it an estimated real-world range of just 165 miles.
The 1.8-liter four-cylinder engine boasts only 110 horsepower instead of the gasoline models' 140 horsepower, so the natural-gas model is expected to feel a bit lazy when merging.