Natural gas is a hydrocarbon - composed primarily of methane (CH₄) - formed from the remains of plants and animals buried under layers of sediment and rock for millions of years. Over time, heat and pressure transform this organic material into natural gas. Natural gas is widely used as a clean and economical energy source for heating, electricity generation, and as a critical feedstock in industries, including those producing plastics, fertilisers, and chemicals. Its clean-burning properties and high energy output make it an attractive option for meeting growing global energy demand while supporting emission reduction targets.

Natural gas has several physical and chemical properties that define its utility and safety. It is non-toxic in usual exposure quantities. The flammability range for natural gas is narrow, with lower and upper explosives around limits of 5% and 15%, respectively, requiring a controlled environment to avoid accidental ignition​. Additionally, natural gas has a high ignition temperature, making it less susceptible to accidental combustion. With a specific gravity between 0.55 and 0.7, natural gas is lighter than air and disperses easily if released, which is advantageous in preventing hazardous accumulations.

In addition to methane, natural gas often contains small amounts of other hydrocarbons such as ethane, propane, and butane, along with trace impurities like carbon dioxide, nitrogen, and hydrogen sulfide. Its typical composition is shown below:



Natural gas is transported in gaseous and liquid forms. In its gaseous state, it is delivered through an extensive network of intraregional and interregional pipelines. Liquefied Natural Gas (LNG) is the liquid form of natural gas obtained by cooling natural gas to -161°C, reducing its volume to 1/600th of its gaseous form, which allows for efficient storage and transport over long distances by specialised LNG carriers.


Upon reaching its destination, LNG is re-gasified and integrated into the local pipeline network for distribution to end users. In some instances, natural gas can also be transported as Compressed Natural Gas (CNG).


Each form of natural gas serves specific purposes depending on transportation logistics, distance, and the infrastructure available. The ability to convert natural gas into LNG has been instrumental in enabling global trade, connecting supply from producing regions to high demand markets that lack pipeline access.

Natural gas originates from both conventional and unconventional sources:


Conventional natural gas is found in large underground reservoirs,  and is relatively easier to extract due to its accumulation in porous rock formations.


Unconventional sources include shale gas, tight gas, and coal bed methane (CBM). Shale gas is trapped within shale formations, requiring advanced extraction techniques like hydraulic fracturing. Tight gas, found in low-permeability sandstone or limestone, also requires specialised methods to access. CBM is extracted from coal seams and is increasingly valuable as a natural gas source. These various sources provide flexibility in meeting global demand, with unconventional gas increasingly supplementing conventional reserves as technology advances and resources become more accessible​.