Compressed natural gas (CNG) carrier ships are those designed for transportation of natural gas under high pressure. CNG carrier technology relies on high pressure, typically over 250 bar (2900 psi), to increase the density of the gas, but it is still 2.4 times less than that of LNG (426 kg/m3). CNG carriers may find their place abreast with the well established technology of liquefied natural gas by LNG carriers as it is economical for medium distance marine transport. Most of the energy consumed for the gas pressurisation can be recovered as electricity using turboexpander while delivering CNG to the inland piping network at unloading jetty/harbour. CNG carriers are also alternate solutions to the undersea pipelines as they have less complicated fast loading and unloading features.