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Natural gas

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Natural gas is a fossil fuel found within geological formations deep underground.

GasDepositDiagram
GasDepositDiagram

It is primarily composed of a gaseous hydrocarbon called methane, which typically makes up about 95% of the mixture. The remaining portion includes small amounts of higher alkanes, along with traces of nitrogen, helium, and carbon dioxide. Because pure methane is colorless and odorless, it is difficult to detect if a leak occurs. To solve this, companies add a commercial odorizer like methanethiol. This chemical creates a smell similar to hydrogen sulfide, which resembles rotten eggs. This addition allows people to identify leaks quickly and stay safe.

Gas underpipe warning notice
Gas underpipe warning notice

The formation of natural gas is a process that takes millions of years. It begins when layers of organic matter, mainly marine microorganisms, settle on the ocean floor. These layers undergo thermal decomposition under oxygen-free conditions. As they are buried deeper, they are subjected to intense heat and heavy pressure. This process converts the energy originally obtained from the sun via photosynthesis into chemical energy. This energy is stored within the molecules of methane and other hydrocarbons.

NatGasProcessing
NatGasProcessing

Before natural gas can be used for heating or electricity, it must undergo processing.

Aderklaa - Gasstation
Aderklaa - Gasstation

Raw gas often contains impurities like water, hydrogen sulfide, and carbon dioxide. Processing removes these substances to make the gas safe for transport and use. This stage also produces valuable byproducts known as natural gas liquids. These include ethane, propane, butane, and pentane. Some technologies, known as gas-to-liquids or GTL, can even convert natural gas into liquid fuels. For example, the Fischer–Tropsch process can produce a synthetic crude oil. Other methods like methanol-to-gasoline can create synthetic gasoline directly.

Humanity has interacted with natural gas for thousands of years. In ancient China, around 400 BC, people used gas from drilling for brines. They transported the gas through crude pipelines made of bamboo to boil salt water. In ancient Greece, natural gas flames at Mount Chimaera inspired legends of fire-breathing creatures. In the United States, William Hart dug the first commercial well in 1821 in Fredonia, New York. For a long time, most gas was used near the well site. It was not until the development of long-distance pipelines in the 1920s that widespread use became possible.

Residential natural gas bill USA 1834
Residential natural gas bill USA 1834

Natural gas is extracted in various ways depending on where it is located. Much of it is "associated" gas, which is found alongside petroleum. In the past, this gas was often seen as a hazard or a byproduct. It was frequently vented into the air or burned off through a process called flaring. Today, the industry also extracts "non-associated" gas from isolated fields. A major recent development is the extraction of shale gas.

BarnettShaleDrilling-9323
BarnettShaleDrilling-9323

Because shale has low permeability, gas cannot flow easily through it. Most modern shale wells require hydraulic fracturing to create artificial cracks. This has led to what some call a "shale gas revolution" in North America.

The scale of the natural gas industry is massive. The world's largest gas field is the offshore South Pars/North Dome field. This field is shared between Iran and Qatar.

World - Natural Gas Production of Countries
World - Natural Gas Production of Countries

Measuring the reserves can be difficult, as different sources provide different numbers. For example, the CIA and EIA suggest Russia has the largest proven reserves, near 47,000 to 48,000 cubic kilometers. However, BP credits Russia with only 32,900 cubic kilometers, placing Iran in the lead. Global demand has continued to increase according to a 2025 IEA report. By 2010, only about 8% of estimated recoverable reserves had been used.

While natural gas is a major energy source, it has a significant impact on the environment. When burned, it emits fewer toxic air pollutants and less carbon dioxide than coal. However, methane is a potent greenhouse gas that contributes to climate change. This happens through a process called radiative forcing, where the gas helps trap heat in the atmosphere.

1979- Radiative forcing - climate change - global warming - EPA NOAA
1979- Radiative forcing - climate change - global warming - EPA NOAA

Venting and unintended fugitive emissions during production can make its carbon footprint as large as other fossil fuels. To meet climate goals, the 2023 IPCC report suggests that new infrastructure must use carbon capture and leak prevention technologies. Without these, new projects risk causing an emissions overshoot.

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🖼️ Images & Media (20)
File:Gas-natural.jpg
Gas-natural.jpg
File:Chuhuo.jpg
Chuhuo.jpg
File:Residential natural gas bill USA 1834.jpg
Residential natural gas bill USA 1834.jpg
File:BarnettShaleDrilling-9323.jpg
BarnettShaleDrilling-9323.jpg
File:Countries by Natural Gas Proven Reserves (2014).svg
Countries by Natural Gas Proven Reserves...
File:GasDepositDiagram.jpg
GasDepositDiagram.jpg
File:Aderklaa - Gasstation.JPG
Aderklaa - Gasstation.JPG
File:NatGasProcessing.svg
NatGasProcessing.svg
File:World - Natural Gas Production of Countries.png
World - Natural Gas Production of Countries.png
File:Polyethylene gas main.jpg
Polyethylene gas main.jpg
File:Gas underpipe warning notice.jpg
Gas underpipe warning notice.jpg
File:Manlove gas storage facility crop.jpg
Manlove gas storage facility crop.jpg

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