What is natural gas?
“Natural gas is a naturally occurring hydrocarbon gas mixture consisting primarily of methane, but commonly including varying amounts of other higher alkanes, and sometimes a small percentage of carbon dioxide, nitrogen, hydrogen sulfide, or helium.” (Wikipedia) To put it in a simple way to understand, natural gas is a gaseous energy source whose main component is methane (CH4). Natural gas exists in the nature, yet it needs to be extracted and processed to become the natural gas we use.
Though natural gas is new to Cambodia, it has been playing a significant role in the world energy market for decades, especially in power sector. In Cambodia’s neighbor Thailand, natural gas contributes to approximately 60–65% of the country’s power generation. In Malaysia, 53% of the electricity is generated by natural gas. In Singapore, a country whose energy market also heavily relies on import, a surprising 95% of its power comes from natural gas.
What do we use natural gas for?
Application 1: Direct Burning for Cooking
Natural gas is widely used for cooking in countries like China and the U.S. In this application, natural gas is supplied through pipe system to stoves of the end users.
Application 2: Direct Burning for Industrial Heating
Thanks to its high calorific value and stable energy supply during combustion, natural gas is a great energy source for those industries that require continuous heating at both high and stable temperature.
The importance of natural gas in global generation may surprise many people. In 2018, natural gas contributed to 23% of the power generated around the world, just behind coal (38%). From the perspective of power generation, natural gas is more efficient and environmentally friendly than other non-renewable energy sources (coal and oil), and more reliable than renewable energy sources (hydro, solar and wind).
The high calorific value natural gas contains and stable energy supply it produces during combustion also make it capable of producing high-temperature steam with stability, therefore, making it a great energy source for those industries that require high-quality steam.
The CCHP application of natural gas is a relatively new concept; it refers to the simultaneous generation of electricity and useful heating and cooling from the combustion of natural gas. This application is ideal for large-scale industrial or commercial complexes which require stable supply of cooling, heat and power.
Natural gas is a gaseous form of energy source, so it can be transported through pipelines from producing regions to markets. But because of the same reason, it is not practical to store natural gas in a large volume, as well as transporting it to places where pipelines are not feasible or do not exist.
The invention of LNG made both possible.
LNG stands for liquefied natural gas. As we can tell from its full name, LNG is natural gas in liquid form. LNG is produced by cooling natural gas down to approximately -162 °C; in the process, not only the temperature and form of natural gas changes, its volume also becomes 600 times smaller. As a result, natural gas becomes a liquid with only 1/600th of its original volume. LNG’s 1/600th volume means much less space is required for storage, and its liquid form means it can be easily contained to be transported.
LNG shares many same characteristics with natural gas: it is colorless, odorless, non-toxic and non-corrosive.
However, LNG has a key difference from natural gas: LNG cannot burn. And because of this key difference, LNG has to be converted back to natural gas in order to be used.
Liquefied Natural Gas (LNG)