For as long as auto emissions present dangers to public health and the environment, car companies will try to find alternative fuel sources to power new vehicles. Compressed natural gas (CNG) is one such source that has become appealing with the U.S. energy boom of recent years, and Ford announced it will have propane and CNG F-150 pickups ready for the 2016 model year. Do they compare favorably to gasoline F-150s for fleet managers looking for greater efficiency? Here’s a comparison of the two.

As for the CNG and propane model, Ford says the 5.0-liter V8 model will be available with a gaseous-fuel prep package that allows fleet managers to fill up on natural gas. The conversion and equipment runs owners $7,500 to $9,500, depending on the size of the fuel tank. Towing capacity will remain unchanged, while payload will have to be adjusted for the weight of the tank conversion. According to the automaker, 2016 models will be able to haul “hundreds of pounds more” than 2014 F-150s.

Ford got the idea to add the fuel prep kit to the new F-150 from surveys taken on its target market. As far as daily fuel costs, savings range anywhere from $0.47 to $1.58 per gallon based on a national average of $2.58 per gallon of gasoline. (Diesel is also consistently more expensive than gas.) Sales of existing CNG models have been on the slow side with 16,821 models in 2014, but more available fuel sources might make it easier for the F-150 on natural gas to gain steam in the marketplace.

As far as emissions are concerned, Ford says the CNG produces 20% fewer emissions than the equivalent vehicle operating on gasoline.

As far as 2015 models running on CNG, there are few models to look at for comparing emissions. The Honda Civic offers one clear test, as there are both CNG and gasoline models available with the 1.8-liter, four-cylinder automatic transmission. CNG models yield 218 grams of greenhouse gas emissions per mile, while the gas model yields 281 grams per mile.

The difference is nearly 25% lower emissions in the CNG Civic, a bit better than Ford estimated for its pickup running on natural gas. Likewise, the premium for a CNG Civic is about $7,500 over that of a standard model, which makes the equation trickier. Fueleconomy.gov says a CNG Civic driver would save about $3,250 on fuel costs over five years compared to a vehicle running at 24 miles per gallon.

Ford will have eight vehicles operating on CNG when the 2016 F-150 hits the market. F-250, F-350, Transit Connect, and E-Series models are already on the road and running on natural gas. Gas prices will likely have a say in how these models perform. As far as emissions are concerned, they are an improvement over gasoline models. Whether they make cost sense for fleet managers will depend on local fuel prices and the cost to upfit your F-150.