What is Liquefied Natural Gas?
Liquefied Natural Gas (LNG) is natural gas converted into liquid form by cooling it to around –161°C at atmospheric pressure. It mainly consists of methane (CH₄), along with small quantities of ethane, propane, butane and nitrogen.
Liquefaction reduces the volume of natural gas to nearly 1/600th of its gaseous volume, making long-distance transportation through specialised ships economically viable. LNG is different from LPG, which primarily contains propane and butane.
How is LNG Produced and Used?
The LNG value chain involves several stages:
- Extraction: Natural gas is extracted from underground reserves.
- Processing: Water, carbon dioxide and other impurities are removed.
- Liquefaction: Purified gas is cooled to about –161°C.
- Transportation: LNG is carried in cryogenic tankers.
- Regasification: It is heated and converted back into natural gas.
- End Use: The gas is supplied to power plants, industries, fertiliser units, households and transport networks.
Why is LNG Important?
LNG has expanded international natural gas trade by allowing countries to transport gas beyond fixed pipeline networks.
- Energy security: Diversifies gas supplies and reduces dependence on individual suppliers.
- Industrial development: Supports fertiliser, petrochemical, refining and other industries.
- Power generation: Provides a flexible source of electricity and can complement renewable energy.
- Global trade: Enables countries without adequate domestic gas resources to access international markets.
- Urban energy: Regasified LNG can supply city gas distribution networks.
LNG and the Energy Transition
Natural gas generally produces fewer direct emissions than coal when burned, making LNG a potential transition fuel. It can also provide flexible generation when solar and wind output fluctuates.
However, LNG remains a fossil fuel. Methane leakage during extraction and transportation, together with emissions from liquefaction and shipping, can reduce its climate advantage. Therefore, its lifecycle emissions must be considered rather than focusing only on combustion emissions.
Environmental Concerns Associated with LNG
Major concerns include:
- Methane leakage across the supply chain.
- High energy requirements for liquefaction.
- Emissions from LNG transportation.
- Boil-off gas during storage and shipping.
- Long-term dependence on fossil-fuel infrastructure.
- Potential infrastructure lock-in that could complicate decarbonisation.
The IEA’s 2026 assessment estimated global average LNG emissions intensity from production through regasification at 18.6 g CO₂-equivalent per MJ of delivered LNG in 2025.
LNG in India
India relies on LNG imports because domestic natural gas production does not fully satisfy demand. According to PNGRB, India had eight operational onshore LNG terminals with combined regasification capacity of about 52.7 MMTPA in 2025.
Imported LNG supports fertiliser production, industries, power generation and city gas distribution.
However, import dependence exposes India to global gas prices, shipping costs, exchange-rate fluctuations and geopolitical disruptions.
Way Forward
India needs to balance energy security, affordability and climate objectives by:
- Reducing methane leakage.
- Improving LNG supply-chain efficiency.
- Diversifying suppliers and routes.
- Better utilising existing terminals.
- Integrating gas strategically with renewable energy.
- Assessing projects on a full lifecycle-emissions basis.
- Promoting electrification, reduced flaring and other emissions-reduction technologies.
Conclusion
LNG provides India and other energy-importing countries with flexibility and supply diversification, but its role in the energy transition remains conditional on controlling methane emissions and improving lifecycle efficiency. A balanced approach can use LNG strategically while accelerating the shift towards renewable and low-carbon energy sources.
FAQs: Liquefied Natural Gas (LNG)
What is Liquefied Natural Gas (LNG)?
LNG is natural gas cooled to around –161°C, converting it into liquid form and reducing its volume to nearly 1/600th of its gaseous volume.
How is LNG different from LPG?
LNG mainly consists of methane, while LPG primarily contains propane and butane.
Why is LNG important for India?
LNG helps India diversify energy supplies and supports fertiliser production, industries, power generation and city gas distribution.
What are the major environmental concerns associated with LNG?
Key concerns include methane leakage, emissions from liquefaction and transportation, boil-off gas and long-term fossil-fuel infrastructure dependence.
What is the role of LNG in India’s energy transition?
LNG can provide flexible energy supply and complement renewable sources, but its long-term role depends on controlling methane emissions and improving lifecycle efficiency.
