In a bid to cut costs and get front-of-the-line privileges at Dallas/Fort Worth International Airport, the biggest taxi company in North Texas plans to convert nearly all of its company-owned cabs from gasoline to compressed natural gas.

Despite a total conversion cost that could exceed $8 million, Yellow Cab president Jack Bewley believes the change will ultimately lower expenses, in large part because compressed natural gas runs about $1.99 a gallon compared to $2.60 for a gallon of regular gasoline. Yellow Cab officials also believe prices of compressed natural gas will be more stable in the long run than those of gasoline.

In addition, Yellow Cab wants to take advantage of a program that DFW implemented late last year allowing taxis fueled by natural gas to jump to the front of the line for fares, Bewley said.

However, a state judge in Dallas this week issued a temporary restraining order putting a halt to the program, court documents show. Bewley declined to comment about how that might impact his company’s plans.

Beyond that, Yellow Cab is a member of a public-private initiative called the North Texas Green & Go Clean Taxi Partnership, which encourages the use of cabs with low emissions of greenhouse gases and other pollutants.

“It’s a major initiative,” he said. The company has 10 natural-gas-powered vehicles on the road at the moment and orders for another 50, he added.

Yellow isn’t the only North Texas cab company that’s going green. For instance, in December, Cowboy Cab announced that it was adding seven natural-gas taxis to its fleet.

Yellow is the largest local cab company as measured by the number of drivers—767—that are authorized to do business at Dallas/Fort Worth International Airport, according to data from the airport.

In addition, the company owns or manages six other taxi services with a combined 325 drivers with authorization at DFW, according to Bewley and airport data. In total, that suggests Yellow and affiliated companies control roughly 52 percent of the airport’s taxi traffic.