The process of applying a direct electric current to two electrodes in water to decompose it into its constituent elements is called electrolysis. In this process, hydrogen gas is released at the cathode and oxygen gas is released at the anode. The rectifier used in the green hydrogen production process must deliver high-quality direct current and have sufficient durability to operate in a humid environment. Because this method produces hydrogen from renewable sources and its byproducts are harmless to the environment, it is called green hydrogen.