When hydrogen is burnt, it emits water vapor, which is why it is marketed as a clean fuel. The important caveat is that hydrogen is only as pure as the energy source utilized to make it. Electrolysis, which employs electricity to split water molecules into hydrogen and oxygen, is one method of producing hydrogen. By splitting water molecules using renewable energy, “green” hydrogen may be produced. There’s also “pink” hydrogen, which is created by nuclear-powered electrolysis.
However, the vast majority of hydrogen generated today is “grey” and emits greenhouse gases. Methane gas combines with high-temperature steam at high pressure to produce grey hydrogen, releasing carbon dioxide in the process. Now, the Biden administration intends to depend on technology that removes CO2 from smokestack emissions to purify grey hydrogen.
