What is the difference between compressed natural gas (CNG) and liquefied natural gas (LNG)?
Since natural gas is a fuel that contains less energy by volume than diesel or gasoline, it is more often used as a compressed (CNG) or liquefied (LNG) gas. These two forms of natural gas that can be used to power vehicles are nevertheless an environmentally friendly and cost-effective alternative to traditional fossil fuels.
However, there are several differences between compressed natural gas and liquefied natural gas.
Storage differences between CNG and LNG
Compressed natural gas is obtained by compressing natural gas under high pressure. This reduces its volume and allows it to be stored in bottles at a pressure of approximately 3,600 pounds per square inch. However, this pressure varies with the outside temperature. In order to prevent the cylinders from being subjected to too much pressure, they are equipped with a pressure relief device that is activated when the heat becomes too intense.
Liquefied natural gas is produced by cooling natural gas to -162°C and must therefore be stored in insulated thermos-like tanks. These are made of highly resistant materials and must meet strict standards. The main disadvantage of LNG is therefore the need for expensive and energy-intensive infrastructure to compress, cool, ship and store it.
CNG and LNG as vehicle fuel: some differences
CNG is the most widely used form of natural gas used to power vehicles. Its use as a fuel dates back to the 1960s. CNG engines can be installed on a wide variety of vehicles including buses and heavy trucks. A single CNG tank can cover about 800 km. Compressed natural gas is very safe and is now available at a few stations located along the main highways. You can even have a private mobile or fixed station installed on your property.
As for LNG powertrains, they are mainly installed on heavy vehicles that require a long operating range. Regardless of the type of engine running on liquefied natural gas, the fuel always reaches the engine in gaseous and non-liquid form. It is only kept in liquid form to increase the quantities of natural gas that can be stored in the tanks.
Find more information on natural gas for vehicles
While both can be used to power vehicles, there are some differences between CNG and LNG. Compressed natural gas is more popular today because of its ease of storage.
EBI has the infrastructure, right here in Quebec, to produce CNG on a renewable basis and offer it to customers who want to reduce their harmful emissions while saving at the pump. Contact our team if you want to switch to compressed natural gas!