Let's say you buy the greenest car you can, one that uses a different kind of fuel, and drive it happily for several years.

What happens when the supply of your fuel suddenly ends, and you can no longer fill up your car?

That's just what happened to Duncan Chalmers of Seattle, who can no longer conveniently get natural gas to fill up his 2008 Honda Civic GX.

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Chalmers wrote us in October, when all three of the public natural-gas fueling stations within 25 miles of his house had closed or announced they would soon do so.

While two commercial fleet fueling stations in South Seattle remain open to the public for now, both are more than 50 miles from his house.

While the Northwest's garbage trucks and commuter ferries, among other vehicles, continue to run on what he calls a "low-cost, domestically abundant, and low-emission fuel," passenger cars powered by natural gas never caught on.

Closed Clean Energy natural-gas fueling station, Seattle

Closed Clean Energy natural-gas fueling station, Seattle

That means, as he says, "We're going back to gasoline even in the face of its environmental impact and climate change."

Chalmers spoke to Clean Energy's Steve McCarthy, who explained that the company was losing money on its public natural-gas stations.

There's little likelihood that privately owned natural-gas vehicles will increase, either.

After more than 10 years of offering a natural-gas Civic, Honda finally threw in the towel and ended production at the end of the 2015 model year.

The family special-ordered its new 2008 Honda Civic GX largely at the behest of the children, who "wanted me to protect the environment," Chalmers said.

"When my son read about the car in a science magazine, he encouraged us to buy one," and that's exactly what they did, paying about $6,000 more than the gasoline model at a time when gas ran as high as $4 a gallon.

Chalmers said he was also "tired of the geopolitical, environmental, and economic issues that oil has created for decades"—and their house already had a natural-gas supply for heating.

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The Civic GX was very good over its tenure and required no major repairs, he said. Its range (about 200 miles) was limited by the pressure tank for the fuel, which took up much of the trunk and held the equivalent of 6 gallons of gasoline.

Originally EPA-rated at 32 MPGe combined, more recent revisions to fuel-economy ratings calculations mean the Civic GX is now rated at 24 MPGe city, 36 MPGe highway, and 28 MPGe combined.

Miles Per Gallon Equivalent, or MPGe, is a measure of how far an alternative-fuel vehicle can travel on the amount of energy contained in 1 gallon of gasoline. Chalmers said the car frequently achieved that revised 36 MPGe in highway use.

Honda Civic GX and Phill natural-gas home filling unit

Honda Civic GX and Phill natural-gas home filling unit

The family often filled up the car overnight using a "Phill" home fueling compressor provided by Honda at a cost of $4,000. But over nine years and 101,000 miles, they wore out two such units. (Honda no longer offers the Phill.)

Refueling locally was fast and easy, with a "sparse but workable" infrastructure—originally four public natural-gas stations.

Vancouver, about 120 miles north in British Columbia, Canada, had good public fueling, so the Chalmers often took the car there.

Cross-country driving in the U.S. wasn't feasible, though: There simply weren't enough natural-gas fueling stations to allow a continuous trip.

And as of October 31, Seattle no longer had any.

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

2008 Honda Civic GX, photographed by owner Duncan Chalmers, Seattle

Which is why the Chalmers traded in their beloved Civic GX on a new Toyota Camry Hybrid, which joined a battery-electric Nissan Leaf in their garage.

"I managed to drive for 16 years without buying a gasoline car," Chalmers said ruefully.

"But now, gasoline is the only fuel we can buy here"—aside from the electricity that recharges their electric car.

EDITOR'S NOTE: This article has been updated to add more specifics on the status of natural-gas fueling stations Chalmers used.

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