Once natural-gas refueling stations are built along our interstate highways, large trucks can run on cheap natural gas.

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The trucking industry calls this the "chicken and egg" problem: which will come first -- LNG trucks or LNG refueling stations?

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According to the website of the U.S. Department of Energy, the country has nine public refueling stations, all located in California.

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But the economics of NGVs are becoming more compelling for taxis, vans and buses that are centrally fueled with limited ranges, and for trucks with established routes where refueling stations can be built every 300-400 miles.

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Use of alternative vehicles such as battery operated and CNG, supported by electric charging stations and a CNG refueling station.

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