Hydrogen appears as an energy carrier due to the need for energy storage and new carriers.
Hydrogen has been used always linked to carbon (in the form of hydrocarbons), but it has been recently when it became necessary to have an energy storage system and new carriers. Here is where the hydrogen appears as an energy carrier, so that in the future it can be used independently.
The utility of hydrogen as an energy carrier lies in the development of fuel cells as systems of transformation of the energy stored in hydrogen into electricity and heat, and its use in domestic, stationary, portable or automotive applications.