Natural Gas, First Strategic Natural Gas Reserves in India

First Strategic Natural Gas Reserves

Context (TH): GAIL is looking at building India’s first strategic natural gas reserves by using old, depleted hydrocarbon wells.
India has 5 million tonnes of strategic petroleum reserves but no storage facilities for natural gas.

GAIL is India’s largest Natural Gas Company, founded in 1984.
It is one of the seven Maharatna Public Sector Undertakings (PSUs) under GoI.
It is under the Ministry of Petroleum and Natural Gas.

Natural gas is a fossil fuel that primarily consists of methane.
Natural gas reserves are deep inside the earth near other solid and liquid hydrocarbon beds like coal and crude oil.
It is not used in its pure form; it is processed and converted into cleaner fuel for consumption.
By-products extracted: Propane, ethane, butane, carbon dioxide, nitrogen etc.
It also contains nonhydrocarbon gases, such as carbon dioxide and water vapour.

Wet gas or Associated gas: Natural gas found in association with crude oil.
Dry gas or Non-associated gas: When reservoirs contain only gas and no oil.
Coalbed methane: Natural gas found in coal deposits.
Sour gas: Natural gases that contain hydrogen sulfide or other organic sulfur compounds.
Sweet gas: Coalbed methane is called ‘sweet gas’ because it lacks hydrogen sulfide.
Shale gas or Tight gas: Natural gas that occurs in the pores of shale, sandstone, and other sedimentary rocks.

Clean burning: Natural gas burns cleaner than other fossil fuels, emitting fewer air pollutants and greenhouse gases.
Efficient: It has a high energy conversion efficiency, minimising waste and maximising utilisation.
Versatile: It can be used for various purposes like cooking, generating electricity, and powering industrial processes.
Flexible: Liquified and compressed natural can be easily transported and stored.

Contributes to greenhouse gas emissions despite cleaner burning.
Methane, a potent greenhouse gas, can leak during natural gas extraction, processing, and transportation.
Natural gas extraction from shale and tight formations often relies on fracking, which can have environmental impacts like water contamination and seismic activity.
Non-renewable: Natural gas is a finite resource that cannot be replenished.
Transportation: Its transportation requires specialised infrastructure.

Underground storage: Utilising depleted gas fields, salt caverns, and other geological formations.
Above-ground storage: Utilising specially designed tanks for smaller-scale storage.

Large capacity
Higher energy efficiency: Natural pressure and temperature in underground formations maintain stored gas in a condensed state, minimising energy losses during storage and retrieval.
Cost-effective
Safe and secure: It minimises the risk of leaks and ensures the safety of the surrounding environment.
Long-term storage
Grid reliability: Underground storage ensures a reliable natural gas supply during peak demand, maintaining grid stability and preventing power outages.

India aims to raise the share of natural gas in its energy mix to 15% by 2030 from the current 6.2%.
The nation consumes around 60 bcm of gas annually.

Liquefied Natural Gas (LNG): Natural Gas liquefied at – 160°C. It facilitates transportation in large volumes in cryogenic tankers across seas/land.
Regasified Liquefied Natural Gas (RLNG): LNG is re-gasified at import terminals before being transported to consumers through pipelines.
Compressed Natural gas (CNG): Natural Gas compressed to a pressure of 200-250 kg/cm² is used as a vehicular fuel. It decreases vehicular pollution.
Piped Natural gas (PNG): Natural gas, distributed through a pipeline with safety valves to maintain pressure, ensures a safe, uninterrupted supply for domestic cooking and heating/cooling applications.