Ford's F-Series pickup, the most popular vehicle in America, presents large-scale opportunities when operated on compressed natural gas (CNG). Last year, natural-gas vehicles saved 400 million gallons of gasoline on U.S. roads, according to one trade group, and emitted about 14% less greenhouse gas on light trucks.
Costs to convert an F-150 half-ton truck are high, though, ranging between $6,000 to $9,500, but fuel costs are lower, with CNG averaging $1.50 less per gallon equivalent than gasoline, according to the Energy Dept. Fleet managers running high-mileage vehicles say they can see a payback in as little as two or three years.