CNG is generally stored at 3000 or 3600 psi when used in a vehicle. Lower pressure means less fuel and shorter range. Natural gas pipeline pressure is only 500 psi and a process must occur to pressurize the natural gas to this higher psi. There are two general methods of compressing and filling natural gas for tranportation:

1. Private/Home - Slow Fill
   • Gas is compressed from your home natural gas line and is pressurized into your vehicle's tank. This process takes a few hours depending on the volume of your tank(s) and the compressor type. You pay for the gas and electricity. Federal (and possibly state/local) incentives are available for the purchase of new equipment.
2. Public - Fast Fill
   • Gas is compressed prior to your arrival and stored in a large tank, of which you transfer a portion to your vehicle. This process takes a few minutes and is comparable to filling your vehicle with gasoline.
   • Not all fast-fill stations are open to the public. Government and private facilities often exist but were built in secure areas where the public is not welcome. Other times, organizations are like toddlers and are not willing to share. Federal (and possibly state/local) incentives may be available for the purchase of new equipment.

A new technology is on the horizon which would not require the high pressure currently required for natural gas vehicles. (Which would potentially help tank shape, tank size, and vehicle range.)