Natural gas is a naturally occurring hydrocarbon consisting primarily of methane. As natural gas flows out of the ground, it may also contain sulphur compounds, nitrogen, carbon dioxide, and other substances. These compounds are removed from the natural gas at processing plants.
Today about one third of Canada's entire energy needs are met by natural gas. It is abundant, relatively easy to transport through pipelines and burns more cleanly than other hydrocarbons. Because of these properties, natural gas has become an important fuel for residential, commercial and industrial applications.
Natural gas was formed millions of years ago as heat and pressure transformed decaying plant and animal matter buried in sedimentary rock layers. The gas is trapped under an impermeable layer of rock that prevents it from flowing to the surface.
Natural gas has been part of Canada’s energy mix since 1859 when it was first discovered in New Brunswick. Natural gas resources are located in British Columbia, Alberta, Saskatchewan, Ontario, Quebec, New Brunswick, Nova Scotia, Prince Edward Island, Newfoundland and Labrador, the Northwest Territories and Yukon. Today, natural gas production is mainly from the Western Canada Sedimentary Basin (WCSB) in British Columbia, Alberta, and Saskatchewan. Atlantic Canada is currently the only region producing natural gas offshore, from areas off the coast of Nova Scotia.
Recovering natural gas
Natural gas is extracted from beneath the earth’s surface using a variety of methods. The method used depends on the geology of the region.
- Vertical drilling: Vertical wells are drilled directly into porous geological formations that hold natural gas.
- Horizontal drilling: Horizontal drilling uses flexible drilling pipe and a steerable drill bit to bend a vertical well at a target depth and then drill horizontally. This technique allows the well to have better access to the natural gas
- Shale gas, tight gas: Natural gas may be found in rock that is porous, but much of the remaining natural gas in Western Canada is trapped in less porous rock – in other words, the formation, which is often shale, is “tight”. Hydraulic fracturing is required to produce natural gas from such formations.
- Hydraulic fracturing: Hydraulic fracturing pumps fluid – a mixture of sand, water and some additives – into the well at high pressure, causing the reservoir rock to crack and releasing the flow of natural gas. This process has been safely used in resource development for more than 60 years.