Natural gas and the national gas grid

Detail

What natural gas is and where it is used

• Natural gas is a fossil fuel made mostly of methane. It is often found with petroleum (crude oil) in the same rocks.
• When crude oil is pumped up, gas comes out with it. This is called associated gas.

• Gas found in a field without oil is called free (non-associated) gas.

• Main uses:

• Power: gas-based thermal power stations.
• Industrial heat: furnaces in glass, ceramics, steel and other industries.
• Feedstock (raw material) for fertilisers: methane is the main input for making urea, a nitrogen fertiliser.
• Petrochemicals: plastics, polymers and chemicals.

• Transport and homes: a fast-growing use through city gas networks.

• Why gas matters: it burns cleaner than coal or oil. It gives off less carbon dioxide, almost no ash and very little sulphur. This is why it is called a "bridge fuel" between coal and renewable energy.

City gas distribution (CGD)

• City gas distribution (CGD) is a local pipeline network inside a town or district. It supplies two products:
• CNG (Compressed Natural Gas): gas squeezed to high pressure and filled into vehicles at CNG stations.

• PNG (Piped Natural Gas): gas sent through pipes to kitchens, shops and factories, much like a water connection.

• PNGRB (Petroleum and Natural Gas Regulatory Board) is the regulator. It gives out CGD licences, one for each Geographical Area (GA).

• Coverage: PNGRB has authorised 307 GAs. These can cover about 100% of India's area and 100% of its population [3].
• Reach (as on 30 September 2024): 1.36 crore PNG (domestic) connections and 7,259 CNG stations [3].

Reserves and producing areas

Basin / field	Location	Key facts
Mumbai High and allied fields (Bassein)	Arabian Sea, offshore Maharashtra, about 160 km off Mumbai	Largest offshore oil-and-gas area; source of gas for the first trunk pipeline
Cambay basin	Onshore Gujarat (Ankleshwar, Kalol and nearby areas)	Old onshore oil-and-gas basin
Krishna-Godavari (KG) basin	Bay of Bengal, offshore Andhra Pradesh	Deep-water KG-D6 block has produced gas since 2009

• Pattern: most of India's gas comes from sedimentary basins. These are thick layers of sand and mud, mainly on the west coast offshore (Mumbai High, Bassein), in Gujarat (Cambay) and on the east coast (KG basin). Assam and Tripura also produce some gas onshore.

Gas pipelines: from HVJ to the national gas grid

• Hazira–Vijaipur–Jagdishpur (HVJ) pipeline:
• Built by GAIL (Gas Authority of India Ltd). It is about 1,700 km long and was India's first cross-country trunk (main) gas pipeline.
• Route: Hazira (Gujarat) → Vijaipur (Madhya Pradesh) → Jagdishpur (Uttar Pradesh).
• It carried Mumbai High and Bassein gas to fertiliser and power plants in western and northern India.

• Why this route: gas landed on the west coast, but the big users were far inland, such as fertiliser plants in the Ganga plains. A pipeline was the cheapest and safest way to move the gas.

• Growth of the network (NCERT: grew from 1,700 km to 18,500 km):

• Operational pipeline: 15,340 km in 2014 → 25,429 km as on June 2025 [2].
• Another 10,459 km is under execution (being built) [2].

• PNGRB has authorised about 34,233 km of pipeline in total, including trunk, spur and tie-in lines [2].

• National Gas Grid ("One Nation One Grid"):

• This is one connected network of trunk pipelines.
• It will link every gas source (domestic fields and LNG import terminals) to every market, including eastern India and the North-East.
• Result: gas can flow wherever demand exists. This lets CGD spread, revives fertiliser plants and reduces regional imbalance.

Pradhan Mantri Urja Ganga (eastern India)

• A GAIL pipeline project. It extends the gas grid to eastern and north-eastern India, which earlier had almost no pipeline gas.
• Route: Jagdishpur (UP) – Haldia (West Bengal) – Bokaro (Jharkhand) – Dhamra (Odisha), later extended towards Barauni – Guwahati to reach the North-East.
• Length: 2,650 km as first planned. It serves 5 states, 40 districts and 2,600 villages [4]. (NCERT-linked figure: about 3,300 km after extensions.)
• Milestone: the 348 km Dobhi–Durgapur section was dedicated to the nation in February 2021 [5].
• Purpose:
• Supply gas to revived fertiliser plants in eastern India (Gorakhpur, Barauni, Sindri).
• Bring city gas to eastern cities such as Varanasi, Patna, Ranchi, Kolkata and Bhubaneswar.

North-East Gas Grid (Indradhanush)

• Indradhanush Gas Grid Ltd (IGGL) is a joint venture of five CPSEs (Central Public Sector Enterprises): IOCL, ONGC, GAIL, OIL and NRL [6].
• Length: 1,656 km. Estimated cost: about ₹9,265 crore. The Cabinet approved Viability Gap Funding (VGF) for it in 2020. VGF is a government capital grant that makes a project worth building when it would not earn enough on its own [6].
• Coverage: all eight NE states: Arunachal Pradesh, Assam, Manipur, Meghalaya, Mizoram, Nagaland, Sikkim and Tripura [6].
• Linkage: it connects to the national grid at Guwahati through the Barauni–Guwahati line.

Beyond NCERT: gas in the energy mix and LNG imports

• Target: raise gas to 15% of the primary energy mix by 2030. In 2022 it was about 6.3% [7], and about 6.7% in 2023 [8].

• Primary energy mix means the share of each fuel (coal, oil, gas and so on) in all the energy a country uses.

• Import dependence: India imports about half of the natural gas it uses, as LNG [8].

• LNG (Liquefied Natural Gas):
• Gas is cooled to about –162 °C. It turns into a liquid that takes up about 1/600th of its volume as gas.
• It is carried by special ships to an LNG terminal.

• At the terminal it is regasified (warmed back into gas) and fed into the pipeline grid.

• LNG terminals:

• 2019: 6 terminals with 39.2 MMTPA (million metric tonnes per annum) capacity. Their capacities were Dahej 17.5, Hazira 5, Dabhol 1.7, Kochi 5, Mundra 5 and Ennore 5 MMTPA [9].
• Now: 8 terminals with about 52.7 MMTPA capacity [10].
• Dahej (Gujarat) is the largest.
• Coast-wise: west coast (Dahej, Hazira and Mundra in Gujarat; Dabhol in Maharashtra; Kochi in Kerala) and east coast (Ennore in Tamil Nadu).

Gas hydrates: a future source

• Gas hydrates are ice-like solids. In them, methane is trapped inside a cage of frozen water molecules.
• Where they form: they need low temperature and high pressure. This is found in seabed sediments on continental margins (the edges of continents under the sea) and below permafrost (ground that stays frozen all year).

• Why they matter: a small volume of hydrate holds a large amount of methane, so they may be a huge future energy store.

• National Gas Hydrate Programme (NGHP) expeditions:

• NGHP-01 (2006) confirmed hydrates in Indian offshore basins, including the KG basin.
• NGHP-02 ran from 3 March to 28 July 2015 off India's east coast [11].
• Its drilling, coring and pressure tests found large, highly concentrated gas hydrate deposits in sand-rich sediments across much of the KG basin [11][12].

• Areas B and C of the KG basin are the best sites for a future production test [11][12].

• Status: hydrates are not yet mined commercially anywhere in India. Key problems:

• It is hard to release the gas safely.
• Methane may leak, and methane is a strong greenhouse gas.
• Taking out the hydrate may make the seabed slope unstable.

Prelims Hooks

• HVJ pipeline = Hazira (Gujarat) – Vijaipur (MP) – Jagdishpur (UP). It was built by GAIL and was India's first trunk gas pipeline (about 1,700 km).
• KG-D6 is a deep-water block in the Bay of Bengal (KG basin, offshore Andhra Pradesh). Gas output began in 2009.
• Pradhan Mantri Urja Ganga route, west to east: Jagdishpur → Bokaro → Haldia / Dhamra. It serves 5 states [4].
• Indradhanush Gas Grid is a JV of IOCL, ONGC, GAIL, OIL and NRL. It covers all 8 NE states with 1,656 km of pipeline [6]. Trap: it is not a GAIL-only project.
• Largest LNG terminal: Dahej (Gujarat). Ennore (Tamil Nadu) is an east-coast terminal. Dahej, Hazira, Dabhol, Kochi and Mundra are all on the west coast [9].
• Gas target: 15% of the energy mix by 2030, up from about 6–7% now [7][8].
• Operational gas pipeline: 25,429 km (June 2025). Authorised: about 34,233 km [2].
• Gas hydrates: methane locked in ice-like solids. They are stable at low temperature and high pressure. Rich deposits are in the KG basin (NGHP-02, 2015) [11]. They are not yet commercially produced.
• CNG is used in vehicles; PNG is used in homes. Both are supplied through CGD networks regulated by PNGRB.

Mains Points

• Spatial imbalance and grid response:
• Gas sources are on the west coast (Mumbai High, Cambay, Gujarat LNG terminals).
• So gas use was long limited to the western and northern HVJ belt.

• The National Gas Grid, Urja Ganga and Indradhanush carry gas to the east and North-East. This helps balanced regional development, revives fertiliser units and spreads city gas [2][4][6].

• Energy security vs import dependence:

• About half of India's gas is imported as LNG [8]. This exposes India to global price shocks.

• Policy responses:

  • Expand domestic deep-water output (KG basin).
  • Expand regasification capacity (to about 52.7 MMTPA) [10].
  • In the long term, develop gas hydrates [11].

• Gas as a transition fuel (GS-III, environment):

• Gas gives off less carbon dioxide and particulate matter than coal.
• Shifting vehicles to CNG and homes to PNG improves urban air quality.

• Gas can also back up renewables, which supports the 15% gas-share target alongside India's non-fossil capacity goals [7].

• Challenges:

• High LNG prices limit gas-based power. Many gas power plants run below capacity.
• Pipeline building is slow in hilly NE terrain.
• The pricing and regulatory system is complex.
• Hydrate extraction carries risks of methane leaks and seabed instability.