In ancient times when lightning ignited natural gas deposits, they were considered supernatural and often worshipped as divine messengers from the gods. Around 500 BC, the Chinese discovered gas as an energy source, using it to boil seawater such that it became drinkable. Britain first commercialised natural gas in 1875, using it to light houses and streetlights.
Natural gas is now the third largest global energy source and accounts for around 21 per cent of energy consumption worldwide.
What is natural gas made from?
Natural gas is a combustible mixture of hydrocarbon gases. Considered a fossil fuel, natural gas is formed in the earth when gases are released from decaying organisms and trapped under pressure over millions of years. Natural gas is mostly compiled of methane (up to 90%) with the remainder sometimes consisting of ethane, propane, butane, carbon dioxide, oxygen, nitrogen, hydrogen sulphide and trace amounts of rare gases.
Natural gas is odourless, colourless, shapeless, non-corrosive and weighs less than air. When processed for energy consumption, it is refined into almost pure methane and the “rotten egg” smell is added to ensure leaks can be detected more easily.
Natural gas is considered 'dry' when it has been processed into pure methane, and ‘wet’ when the other hydrocarbons are present.
‘Wet’ natural gas extracted from crude oil deposits is often refined into LPG (Liquefied Petroleum Gas). This synthesised gas is used as fuel in heating appliances and vehicles. Increasingly it is used as an aerosol propellant and refrigerant, replacing chlorofluorocarbons.
What is natural gas used for?
Natural gas is one of the world’s cleanest, safest and most useful sources of energy. Until the early 1900s, gas was only available to markets that could connect to the gas source via a direct pipeline. In 1873 a refrigerating machine was invented in Munich for compressing gas into liquid, and in 1912 the first Liquefied Natural Gas (LNG) plant was built in Virginia, USA.
Compressing natural gas into a liquid provided for easier storage and transport. After proving in the 1940’s that LNG could be safely transported, a worldwide market was created such that countries without natural gas reserves could use it for energy purposes. After transport, the LNG is re-gassed and delivered through a direct pipeline to the end-user.
The major sectors that consume natural gas include manufacturing, electricity generation, mining and the residential market (used for water heating, cooking and heating the home).
Where is natural gas found?
Natural gas can be found in oil fields, natural gas fields and coal beds. When found with crude oil deposits in the early 1900’s it was often burned off as a by-product of oil drilling. Now gas is usually re-introduced into the deposit to allow for future production when the market demands.
According to the Australian Energy Resource Assessment
, global gas reserves were estimated at around 7.2 million picojoules (PJ) or 6534 trillion cubic feet (tcf) at the end of 2008. This will provide more than 60 years’ supply at current production rates. While information is limited, global unconventional gas resources in place are estimated to be more than four times this amount, in the order of 35.8 million PJ (32 500 tcf).
Australia’s gas production attributed close to 2 per cent of global gas reserves in 2008. Approximately 92 per cent of Australia’s natural gas reserves are located in Western Australia, in the Carnarvon, Browse and Bonaparte basins.
Visit our Energy
page for more information about other sources of energy. You can use the following references:
Visit our Oil, Gas and Energy
page for more information about the Oil and Gas industry.