Natural gas is a fossil fuel that is found in underground rocks known as reservoirs and can be extracted through drilling wells. It is a relatively clean burning fossil fuel that has 40% less carbon dioxide emissions than coal and an estimated 20% less than oil. For this reason, natural gas or liquefied natural gas (LNG) is considered a cleaner solution for our growing energy needs. In this article, we will explore how LNG is produced, transported, and stored, what it’s used for, how it impacts the environment, and its role in the gas supply market.
What is Liquefied Natural Gas (LNG)?
Liquefied natural gas (LNG) is natural gas that has been cooled to a temperature of -260°F (-162°C) to turn it into a liquid. This liquid form enables the gas to be transported and stored until it needs to be regasified and used as an energy source elsewhere. LNG is odorless, colorless, non-corrosive, and non-toxic. It is also the cleanest of the fossil fuels, producing 40% less carbon dioxide (CO2) than coal and 30% less than oil. It does not emit sulfur dioxide (SO2), nitrogen oxides (NOx), or particulate matter (PM) when burned, making it a cleaner alternative to other fossil fuels.
How is Liquefied Natural Gas Made?
Liquefied natural gas is produced by purifying natural gas and super-cooling it to -260°F to turn it into a liquid. During the process known as liquefaction, natural gas is purified to remove impurities such as water, carbon dioxide, and sulfur. The purified gas is then cooled to -260°F, at which point it becomes a liquid. The liquid is stored in insulated tanks until it is ready to be transported. The process of liquefaction reduces the volume of natural gas by a factor of 600, making it easier and more cost-effective to transport and store.
How is Liquefied Natural Gas Transported?
Liquefied natural gas is transported in specialized tankers that are designed to keep the gas at a temperature of -260°F. These tankers are double-hulled and have a layer of insulation to keep the gas cold. The tankers are also equipped with a system that keeps the gas at a constant temperature during transport. Once the tanker reaches its destination, the LNG is regasified and transported through pipelines to its final destination.
What is Liquefied Natural Gas Used For?
Liquefied natural gas is used for a variety of purposes, including:
- Power generation: LNG is used to generate electricity in power plants. It is burned to produce steam, which drives a turbine to generate electricity.
- Heating: LNG is used for heating in residential, commercial, and industrial settings.
- Transportation: LNG is used as a fuel for ships, trucks, and buses. It is also used as a fuel for locomotives in some countries.
- Industrial processes: LNG is used as a feedstock in the production of chemicals and other products.
How Does Liquefied Natural Gas Impact the Environment?
While liquefied natural gas is a cleaner alternative to other fossil fuels, it still has some environmental impacts. The production and transport of LNG can result in emissions of greenhouse gases, such as methane, which is a potent greenhouse gas. Methane is released during the production and transport of natural gas, and it is estimated that up to 3.6% of natural gas produced is lost to the atmosphere. The use of LNG can also result in emissions of nitrogen oxides (NOx) and particulate matter (PM), which can contribute to air pollution.
Conclusion
Liquefied natural gas (LNG) is a cleaner alternative to other fossil fuels, producing 40% less carbon dioxide (CO2) than coal and 30% less than oil. It is produced by purifying natural gas and super-cooling it to -260°F to turn it into a liquid. LNG is used for power generation, heating, transportation, and industrial processes. While LNG is a cleaner alternative to other fossil fuels, it still has some environmental impacts, such as emissions of methane, nitrogen oxides, and particulate matter. As the world moves towards net-zero carbon emissions and renewable energy sources, LNG may be the ‘clean’ fossil fuel that’s best-placed to help us transition to a carbon-free future.