Chrysler’s sold CNG vehicle is the Ram 2500 heavy-duty pickup, which is capable of traveling up to 255 miles powered by the fuel.

Chrysler says it has developed a tank to store compressed natural gas that mimics human lungs and will allow the cheaper fuel source to more easily be used in automobiles.

The design uses smaller compartments inside a larger tank to increase fuel capacity and storage, similar to the alveoli within the human lung. It would free automakers from being forced to use large reinforced cylinders to store compressed natural gas onboard automobiles and would allow fuel to be stored within non-cylindrical shapes.

Eric Mayne, a Chrysler spokesman, said the automaker won’t discuss how or when the technology will be used on future automobiles.

Chrysler currently offers one CNG vehicle: a Ram 2500 heavy-duty pickup capable of traveling up to 255 miles powered by the fuel. The pickup is also equipped with a 35-gallon reserve gasoline tank that extends its total range to 745 miles. It is powered by a 5.7-liter Hemi V-8 engine capable of burning both gasoline and CNG.

The CNG Ram uses a large box behind the cab and within the bed of the pickup to store its large cylindrical CNG tank. Chrysler says the new technology will allow future CNG tanks to be odd-shaped and packaged in a way to better conform to the design of the vehicle.

Though it is less energy-dense than gasoline, CNG is about one-third the cost thanks in large part to new drilling technology that has freed previously untapped deposits of natural gas in the Earth’s crust.