Driving 5,000 Miles in Honda’s Civic Natural Gas

We’ve been intrigued by Honda’s Civic natural gas program since this vehicle began serial production at the automaker’s Ohio assembly plant in 1998.

It is a pretty amazing car, built alongside its conventionally powered cousins on the same line, but with the unique components that enable it to operate on clean compressed natural gas (CNG) – a high-compression engine with hardened valves and other natural gas- specific hardware, special lines and fittings, a pressure vessel instead of a gas tank, and so on. It may be equipped with different components, but in the end the natural gas variant drives like the gasoline Civics that leave the plant.

This is a good thing since ‘transparency’ is important. While most drivers may want environmentally-conscious vehicles, they tend to also want ones that are familiar in most ways. The 2012 Honda Civic Natural Gas  – Green Car Journal’s 2012 Green Car of the Year –has been showing us how well Honda has accomplished this job since it began operating as part of our long-term test fleet in 2012.

The natural gas variant’s 1.8-liter engine delivers 110 horsepower – 30 less horsepower than the gasoline version – although the difference isn’t really noticeable during the daily drive. The thousands of miles we’ve now spent behind the wheel bear this out.

The CNG version Civic is not only mainstream-stylish and comfortable, it’s also fuel efficient. We averaged better than 36 highway mpg on a recent tank with another tank in city driving averaging 26 mpg. This was done in ECON mode, with Honda’s ECO Assist system engaged to modify engine operation and other power-using systems to increase driving efficiency. Our combined mpg readings have been averaging 30.8 mpg combined fuel economy, right where it should be considering EPA’s 31 mpg combined estimate.

We’ve found that engaging the ECON function helps mpg but does diminish throttle response, so entering interstates may be best done with ECON off. With ECON on or off, though, the Civic Natural Gas provides the kind of solid driving experience we can appreciate.

Honda mounts the Civic’s 3600 psi tank between the rear wheels, a position that also places it partially in the rear of the trunk behind a finished panel, resulting in a substantially smaller trunk volume than conventional Civics. The tank holds the equivalent of about eight gallons of gasoline, depending on ambient temperatures during refueling since temperature can influence fill volume. Our range at fill-ups typically shows about 220 to 240 miles on the car’s distance-to-empty gauge.

The Civic Natural Gas test car we’re driving offers an array of welcome features including Honda’s navigation system, which bumps the price up $1,500 from this model’s base MSRP of $26,155 to $27,655.