In recent years, hydrogen energy has been mentioned many times. Do you know what is hydrogen? Let me to explain it to you!
Hydrogen is the first element on the periodic table and the lightest element. In Greek, its name means "creator of water" or "water source", and the English word “Hydrogen” also means hydro (water) gen (creator), indicating the close relationship between hydrogen and water. Before being officially named, hydrogen was referred to as "inflammable air". The Chinese name for hydrogen gas originally referred to "light gas".
Perhaps many people have heard of green hydrogen, blue hydrogen, and gray hydrogen. However, these do not refer to the color of hydrogen gas, which is colorless and odorless. Instead, they distinguish the level of environmental friendliness and energy consumption in the process of hydrogen production.
Gray hydrogen is produced by using fossil fuels (oil, coal) to generate electricity and separate hydrogen from water. The by-products emitted during the production process contain carbon dioxide and are not renewable. The advantage is that the technology is mature, the output is large, and the cost is low, but the disadvantage is that it is not environmentally friendly.
Blue hydrogen is based on gray hydrogen but undergoes decarbonisation to reduce carbon emissions before extracting hydrogen. The advantage is that it has a large output, low cost, stability, and is more environmentally friendly. However, hydrogen produced in this way has lower purity and still requires the use of fossil fuels.
Green hydrogen is produced by renewable energy sources such as solar or wind power to generate electricity, and then using the electricity to electrolyze water to obtain hydrogen and oxygen. The process is basically zero-carbon emissions, can be infinitely recycled, and is pollution-free.
After learning about these three types of hydrogen, it is clear that they are not describing the color of hydrogen gas!
Please stay tune of our next post which we will introduce the history of using the hydrogen.