More than 2,600 trillion cubic feet (Tcf) of natural gas reserves are considered as stranded internationally, outside of North America (i.e., not connected to production). This figure is essentially equal to the 2,800 Tcf currently connected to production. The total world reserves, including North America, are around 7,000 Tcf. Confusing the situation and putting impediments to smooth development, in contrast to oil, is the enormous disparity among natural gas prices in various parts of the world: $1/MMBTU in Russia, $2.5 in the US, $8 in Europe, $16 in the Far East. Lack of adequate and diversified transportation is the reason.
It has been repeated often that oil is "fungible" and hence easy to transport with pipelines or easy to load and unload tankers, whereas natural gas is not. Natural gas can be transported with on-land pipelines but it gets rather expensive with underwater pipelines. Traditionally, the cost per length of offshore pipelines has been considered ten times the onshore cost. The main alternative has been liquefied natural gas (LNG) but other options have been offered such as compressed natural gas (CNG) and the chemical conversion of gas to transportable fuels, collectively called gas-to-liquids (GTL). The latter has changed over the years with alcohols getting new prominence.
This work presents new information from recent experiences and attempts to provide a methodology of optimization for the transportation options for natural gas. Emphasis is given to new CNG technologies. Guidelines and new limits are presented to provide the appropriate means of transportation and reduce the volume of stranded gas currently in place. Worldwide demand for natural gas is expected to force the issue because of massive new needs, headed by China.