natural gas (primarily methane) that has been liquefied for ease of storing and transporting. LNG takes up about ¹/₆₀₀ the space that natural gas does in its gaseous form, and it can be easily shipped overseas. LNG is produced by cooling natural gas below its boiling point, -162° C (-259° F), and is stored in double-walled cryogenic containers at or slightly above atmospheric pressure. It can be converted back to its gaseous form by simply raising the temperature.

LNG is more practical than liquefied petroleum gas (q.v.) or other liquid gases, particularly for use in large volumes, because it has the same chemical composition as natural gas. This fact and the growing demand for natural gas have stimulated LNG production. Moreover, LNG technology has made it possible to utilize natural gas from remote areas of the world where it previously had no commercial use and was flared (burned). Special tankers transport LNG from such countries as Algeria, Borneo, and Indonesia to markets in Europe, Japan, and the United States.