CNG LPG ECU, whose main component is methane, is recognized as the cleanest fossil energy source on earth. It is colorless, odorless, non-toxic and non-corrosive. Its volume is about 1/625 of the same volume of gaseous natural gas, and the mass of LNG is only about 45% of the same volume of water.

The manufacturing process is to first purify the natural gas produced in the gas field, after a series of ultra-low temperature liquefaction, and then transport it by liquefied natural gas ships. Liquefied natural gas has very little air pollution after combustion, and it emits a lot of heat, so LNG is a relatively advanced energy source.

Liquefied natural gas is natural gas that is compressed and cooled to its freezing point (-161.5°C) and then becomes liquid. Generally, LNG is stored in a low-temperature storage tank at -161.5°C and 0.1MPa. Its main component is methane, which is transported by special ships or tankers and re-gasified when used. Since the 1970s, the world's LNG production and trade volume have increased rapidly. In 2005, the international LNG trade volume reached 188.81 billion cubic meters. The largest exporter was Indonesia with 31.46 billion cubic meters; the largest importer was Japan 76.32 billion cubic meters.

Advanced environmental protection countries in the world are promoting the use of CNG LPG ECU. In addition to being used as fuel for power plants, factories, and household users, the methane contained in it can be used as chemical raw materials such as fertilizers, methanol solvents and synthetic acetic acid; The contained ethane and propane can be cracked to produce ethylene and propylene, which are important raw materials for plastic products.