The debate on whether liquefied natural gas (LNG) is a clean and sustainable source of energy is complex. In this Molgás article, we analyse its advantages and disadvantages, identify environmental challenges and address other frequent concerns, such as ‘is LPG dangerous?’, ‘LNG and the enviroment’, ‘is LNG clean?’ and ‘LNG and sustainability’. We will explore the current scientific evidence and provide you with a comprehensive, informative and non-commercial overview.
What is LNG? (Basic context)
LNG is natural gas converted into a liquid at about -160 °C, which reduces its volume by about 600 times. This transformation facilitates transport by ship, train or lorry to non-pipeline locations. It is then regasified for use in power generators, heaters, ships, vehicles and industrial processes.
Benefits of LNG in terms of ‘clean’ energy
Reduces CO₂ emissions compared to other fossil fuels
- Compared to coal, it emits up to 50% less CO₂; compared to oil, up to 30 % less.
- Its combustion generates less nitrogen oxides (NOx), sulphur (SOx) and particulate matter, improving air quality.
Bridge fuel in the energy transition
It is considered a ‘bridge fuel’ – flexible and compatible with renewable energies, it provides stability when these are not constant. Combined cycle plants, for example, can be adjusted quickly.
Maritime and industrial transport
- On ships, it substantially reduces polluting emissions compared to diesel or heavy fuel oil.
- In industry and power generation, it is efficient and cleaner than other fossil fuels.
Disadvantages: risks in the LNG chain
Methane leaks – a serious problem
- Burning LNG may be clean, but methane leaks are a major concern: trapped in the atmosphere, methane is ~23 times more potent than CO₂.
- A report points out that up to 8.8% of total emissions from the LNG cycle come from leakage.
LNG and sustainability –
can it be considered sustainable?
Methane mitigation needed
For LNG to be sustainable, methane leakage must be limited at each stage of the cycle. Advanced technologies and continuous monitoring are key. In addition, methane and CO₂ capture (CCS) can greatly reduce their impact.
Role in areas with energy deficits
In regions with a lack of grid power or coal dependency, LNG has ‘improved energy security’ and reduced pollutants. However, its use must be backed by investment in renewable energy and efficiency panels.
Comparison with LPG – is LPG dangerous?
Although this is not the central question, it is worth comparing them:
- LPG (propane/butane): produces 20% less CO₂ than petrol, 10% less than diesel and also reduces NOx and particulates.
- However, LPG does not contain methane and its infrastructure (cylinders, vehicles) poses a risk of leaks or explosions.
- In terms of impact, LNG can offer a greater reduction in pollutants if methane is well controlled, but it requires more investment and infrastructure.
Conclusion and bottom line
| Aspect | Advantages of LNG | Risks/Disadvantages |
| CO₂ vs. coal/oil | -50 % and -30 % respectively | – |
| Air quality | Lower NOx, SOx, particulate matter | – |
| Chain emissions | – | Methane (up to 8.8%), CO₂ from liquefaction and transportation |
| Energy transition | Efficient bridge fuel | Investment in renewables may stall if not regulated |
| Energy security | Provides stable supply | Long-term infrastructure investment |
To sum up, LNG can be seen as a transitional energy source: cleaner than other fossil fuels and useful for supporting the growth of renewables.Ultimately, LNG is not an inherently ‘clean energy’ or ‘fully sustainable’ fuel, but it can play a useful role if managed carefully, transparently and with a long-term vision towards a renewable world.