Context: Net imports of natural gas by India, the world’s fourth largest importer of liquefied natural gas (LNG), is expected to grow at an average of 4.9 per cent annually between 2022 and 2050.
What is Natural gas?
- Natural gas is a fossil fuel formed from the plants, animals, and microorganisms that lived millions of years ago.
- As plants, animals, and microorganisms decompose, they are gradually covered by layers of soil, sediment, and sometimes rock. Over millions of years, the organic matter is compressed. As the organic matter moves deeper into Earth’s crust, it encounters higher and higher temperatures.
- The combination of compression and high temperature causes the carbon bonds in the organic matter to break down. This molecular breakdown produces thermogenic methane—natural gas.
- Composition?
- Methane 97% (CH4)
- Ethane 0.919% (C2H6)
- Propane 0.363% (C3H8)
- Butane 0.162% (C4H10)
- Carbon dioxide 0.527% (CO2)
- Oxygen 0-0.08% (O2)
- Nitrogen 0.936% (N2)
- Other noble gases (e.g., He, Ne, Ar, Xe)
Natural gas formation:
- Sedimentary basins trap huge reservoirs of natural gas.
- Natural gas deposits are often found near oil deposits.
- Deposits of natural gas close to Earth’s surface are usually dwarfed by nearby oil deposits.
- Deeper deposits—formed at higher temperatures and under more pressure—have more natural gas than oil.
- The deepest deposits can be made up of pure natural gas.
Biogenic vs thermogenic Methane:
- Thermogenic methane is produced deep within the seafloor when organic material is degraded by the earth's heat.
- Biogenic methane is produced as a waste product when microorganisms called methanogenic archaea eat organic material; these microorganisms can only produce methane in reducing environments.
- Methanogens live in the intestines of animals (including humans) and in low-oxygen areas near the surface of Earth. Landfills, for example, are full of decomposing matter that methanogens break down into a type of methane called biogenic methane. The process of methanogens creating natural gas (methane) is called methanogenesis.
Note: Although most biogenic methane escapes into the atmosphere, there are new technologies being created to contain and harvest this potential energy source. Thermogenic methane can also escape into the atmosphere. Some of the gas is able to rise through permeable matter, such as porous rock, and eventually dissipate into the atmosphere.
| Conventional Natural Gas | Unconventional Natural gas |
| Conventional gas is trapped in permeable material beneath impermeable rock. Economical to extract and easily accessible. | Biogas Deep Natural Gas Shale gas Tight gas Coal Bed methane Methane hydrates |
Natural gas in India:
- India’s geography heavily affects access to both its natural resources and to its natural gas imports.
- India does not import natural gas via pipeline, partially due to the deserts and mountains forming much of its northern border. As a result, domestic production and liquefied natural gas (LNG) imports remain the primary sources of India’s natural gas supply.
- Most domestic production in India, about two-thirds in 2019, is from offshore production fields.
- India uses a complex pipeline infrastructure to link offshore natural gas production and LNG imports that arrive at coastal import terminals to the rest of the country.
- Presently in India the share of natural gas in energy basket is 6.7%. The Government has set a target to raise the share of natural gas in energy mix to 15% in 2030.
- Methane emissions in India:
- Acc to IEA, India=2nd largest methane emitter.
- The two predominant sources of methane emissions in India are enteric fermentation and paddy cultivation.
According to the report, India’s industrial sector—in particular, ammonia production intended to decrease fertilizer imports—as well as a growing oil refining sector will drive most of the growth in natural gas consumption over the projection period.
