Liquefied Natural Gas

An emerging LNG industry offers an opportunity to bring economic benefits to Canadians

Body Explore Topics Liquefied Natural Gas LNG Tanker

What is Liquefied Natural Gas (LNG)?

Natural gas, when produced and used domestically, is shipped in its vapour form through a network of distribution pipelines to a local distribution company and then delivered to a customer.  

When natural gas is shipped to a distant foreign market outside of where it is produced, the natural gas needs to ‘shrink in size’ or be compressed in order to ship large volumes economically – this liquefies the natural gas. The ‘shrinking’ of natural gas reduces its size by a factor of about 600. The ‘shrinking’ is done through the LNG process.

The process – There are three primary phases involved in LNG:

Body Explore Topics Liquefied Natural Gas LNG Graphic

Phase 1 – Liquefaction

Liquefaction or shrinking begins after natural gas is transported via pipeline from the natural gas field to the liquefaction facility. Here impurities are removed leaving a product that is primarily methane with small amounts of nitrogen and other hydrocarbons. The natural gas is cooled to about -161°C when it becomes liquid. The liquid natural gas is stored in insulated tanks to keep it cold until it is ready to ship.

Phase 2 – Transportation/storage

At the liquefaction facility, the liquid natural gas runs through a pipeline where it is pumped into double-hulled LNG carriers designed for long marine hauls. These carriers are designed to keep the liquid natural gas cold and minimize evaporation. LNG carriers can hold up to 9.4 million cubic feet of LNG, which is equivalent to 5.6 billion cubic feet of natural gas in its natural gaseous state.  

Phase 3 – Re-gasification/storage

When the LNG carrier arrives at its destination, the LNG is offloaded and stored in insulated storage tanks to keep it cold. When needed, the LNG is warmed to convert it back to a gaseous state and is then delivered by pipeline to customers.

Key facts about LNG:

  • Natural gas is cooled to -161°C when the natural gas becomes liquid.
  • LNG is a clear, colourless, odourless, non-toxic liquid.
  • LNG reduces its volume by about 600 times from the gaseous state.
  • LNG carriers can hold up to 9.4 million cubic feet of LNG, which is equivalent to 5.6 billion cubic feet of natural gas in its natural state.
  • More than 135,000 LNG carrier voyages have taken place without major accidents, safety problems, or security issues either in port or at sea. (Source: Centre for Liquefied Natural Gas)
  • Asian markets are an eight-day to 11-day sail from proposed LNG facilities on Canada’s West Coast.

Success Story – Using LNG at home

The two largest ferries in the BC Ferries fleet, the Spirit of British Columbia and the Spirit of Vancouver, will be converted to use liquefied natural gas (LNG) as their fuel source. The first ship will be converted in 2017/18 and the second ship will be upgraded the following year. BC Ferries says the conversion to LNG saves money and reduces CO2 emissions by 12,000 tonnes annually, which is the equivalent of taking 2,500 vehicles off the road per year. The ships service the Tsawwassen – Swartz Bay run, the busiest route in the fleet.