Compressed Natural Gas (CNG)


  • Is clean, fairly inexpensive and available from domestic reserves
  • Has a higher octane rating, allowing for higher compression ratios and efficiency
  • Is pressurized fuel contained in a sealed system and is therefore less likely to cause contamination
  • Vehicle refuelling appliance configurations are available for commercial and residential applications


  • Vehicle conversions are expensive (approximately $6,000)
  • CNG storage tanks take up vehicle storage space
  • Refuelling infrastructure is not widely available

Compressed natural gas (CNG) is an environmental alternative to fossil fuels, mainly consisting of compressed methane (CH4) gas. The combustion of methane results in fewer greenhouse gas emissions. It is stored and distributed in cylindrical containers, usually at 200-275 bar (197-271 atm).

Specific equipment must be added to traditional internal combustion engine vehicles to accommodate the CNG. These include a pressure regulator – a device that converts the natural gas from storage pressure to injection pressure – and gas injectors that meter the CNG being injected into the engine. Although these additions are possible, they usually come with a high price tag (approximately $6,000).

CNG may be confused with liquefied petroleum gas (LPG), which is similar but involves a number of other hydrocarbon gases in liquid form. The advantage of CNG over LPG is that it does not require expensive cooling processes and cryogenic tanks. However, CNG does require a larger volume to store the same mass of gasoline as well as the use of very high pressures.

Although commercial distribution networks are not widely available, Canada is one of the largest producers of natural gas in the world. With less reliance on foreign supplies of energy, CNG creates jobs and investment opportunities in Canada.