Is LNG always refrigerated?

 

Yes, Liquefied Natural Gas (LNG) must always be kept at cryogenic temperatures—typically below -162°C (-260°F)—to remain in a liquid state at or near atmospheric pressure. [1, 2]

If the temperature rises above this level, the liquid turns back into gas, which is why it is stored in specialized, heavily insulated tanks to maintain these low temperatures. [1, 2]

Here are key details regarding the storage and "refrigeration" of LNG:

• Autorefrigeration: LNG is often stored as a "boiling cryogen," meaning it keeps itself cold. Much like boiling water stays at 100°C (\(212^{\circ}F\)) because the heat escapes with the steam, LNG remains at a constant, extremely low temperature as some of it "boils off" (evaporates) and is removed, keeping the remaining liquid cold. [1, 2, 3, 4, 5]
• Storage and Transport: LNG is kept in double-walled, vacuum-insulated tanks on ships and at storage terminals to prevent heat from entering. [1, 2, 3, 4, 5]
• The Alternative (CNG): Unlike LNG, Compressed Natural Gas (CNG) is stored at room temperature but under extremely high pressure. [1, 2, 3]

In short, "liquid" natural gas cannot exist at normal atmospheric temperatures without being under massive pressure, so it is always maintained through cryogenic cooling. [1, 2, 3, 4]