EXCEPT THAT GAS IS RAPIDLY HEADED BACK UNDER $3:

Beyond the chemical, mechanical and economic challenges of getting natural gas into the vehicle fleet, there are psychological barriers. The average person doesn't think about natural gas when thinking of alternative vehicles, says Mike Omotoso, senior manager for LMC Automotive U.S., a research firm. "They might think of diesels, but they mainly think of gas-electric hybrids or plug-in electrics. They just aren't aware of natural gas."

Much of how the public will react is unknown. Will there be safety fears? Will people be willing to use the same fuel that heats their houses to run their cars? There's no wide-scale effort to answer those questions.

The arguments that will win over buyers aren't clear either. Honda used the cleaner-emissions pitch when its Civic GX came on the U.S. market in 1998, says Brad Johnson, corporate fleet director with Pacific Honda in San Diego. Now, he says, buyers seem more interested in saving at the pump and using a fuel produced in the U.S. Honda is also promoting the fact that CNG vehicles can drive in high-occupancy-vehicle lanes on California freeways.

Even though consumers are slow to adopt natural-gas passenger vehicles, at least a few gas retailers are optimistic that if they build it, drivers will come.

Love's Travel Stops & Country Stores, of Oklahoma City, plans to open 10 retail outlets with CNG pumps this summer, thanks to a partnership with Chesapeake Energy.

And Kwik Trip Inc., an operator of gas stations and convenience stores, opened its first CNG station aimed at passenger-car drivers in La Crosse, Wis., this spring, with plans for several more.

"It's attractive to customers because it's a domestic product, there's a steady supply, and the price is right," says John McHugh, Kwik Trip's communications manager. "If we can offer the consumer a value, we know people will jump on the bandwagon."

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