Hydrogen is a colorless, highly flammable gas. Like many other gases, hydrogen rarely appears in a pure form on Earth. Hydrogen is not a fuel or source of energy – by itself! Once hydrogen burns, it reacts with oxygen and creates tremendous heat. So the heat is used for energy then. Pure water and a few nitrogen oxides are the by-products only. Therefore, hydrogen is considered as an energy carrier.
Fortunately, there are ways of producing hydrogen fuel, such as electrolysis using hydroelectricity, solar, wind, and nuclear power. As a fuel, hydrogen has been used safely for many decades in a wide range of applications, including food products, metals, glass and chemical industries.
The global hydrogen industry is well established and produces more than 50 million tons a year these days.