They all use natural gas – what’s the difference between LNG and CNG?

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When it comes to LNG vehicles, people often mention their other \"brother\" – CNG (compressed natural gas) vehicles. In fact, LNG and CNG are just different in form; the former is in liquid state while the latter is in gaseous state. LNG can be converted into CNG by gasification and then pressurization. 　　In recent years, as environmental concerns have become increasingly severe, natural gas has been regarded by many as the preferred clean energy source, and fuel vehicles powered by natural gas engines have also become a topic of interest. In cities, many buses and taxis have switched from using fuel to natural gas. Observant people may have noticed that some vehicles are labeled as LNG, while others are labeled as CNG. Today, let’s talk about the differences between LNG and CNG. Both use natural gas, so what are the differences between LNG and CNG? 　　The same – both use natural gas. LNG vehicles and CNG vehicles both run on natural gas and are considered clean energy vehicles ； The main component of fuel is methane, and the two are very similar in terms of physical and chemical properties, fuel efficiency, and calorific value ； The exhaust gases emitted generally contain no sulfides or dust particles. 　　In terms of riding comfort, there is no significant difference between LNG vehicles and CNG vehicles. The LNG bus that the reporter rode in as part of the convoy was 6 years old; it started moving and drove smoothly throughout the journey, with hardly any noise from the engine to be heard. 　　Different – various forms. LNG vehicles use liquid natural gas at low temperature and normal pressure as fuel, while CNG vehicles use gaseous natural gas at high pressure as fuel. 　　Since the volume of liquid natural gas is about 1/600 that of gas at the same quantity, LNG offers a higher storage efficiency – 2.5 times that of CNG of the same volume. This gives LNG vehicles a greater range, typically exceeding 600–700 kilometers, making them particularly suitable for heavy trucks and long-distance buses ； In contrast, the range of CNG vehicles is generally within 250 kilometers, making them suitable for small passenger cars, buses, and small freight vehicles. 　　Furthermore, since LNG is produced by cooling gaseous natural gas to minus 162 degrees Celsius at normal pressure to turn it into a liquid, when an LNG vehicle is not in use, the low-temperature liquid inside the tank vaporizes as the external temperature rises. When the pressure exceeds the setting of the exhaust safety valve, the tank automatically releases pressure by expelling some of the natural gas. Therefore, LNG vehicles are not suitable for being parked in enclosed spaces such as garages, and this is one of the main reasons why there are no LNG-powered compact cars. Liquefied Natural Gas Operation License