In a society that is progressing towards an increasingly sustainable future and that tries to reduce total emissions to the atmosphere, the current hydrogen production systems based on the electrolysis of water in combination with renewable energy sources are considered as a resource of great potential. Both to obtain clean hydrogen and to minimize the fluctuations of renewable energies using hydrogen generated as an energy store.
Hydrogen is the most abundant chemical element that exists in the universe but it is not in free state but is combined with other elements, so it is not a natural resource, but an energy vector. Hydrogen can be produced from a wide range of energy sources such as water, fossil fuels or biomass, among others, through different processes depending on the raw material and the energy source used. The main processes to obtain it are electrolysis, gasification, reforming, biological processes or thermolysis. Due to the diversity of resources from which it can be produced, the use of the hydrogen vector implies greater security of supply and greater access to energy.
To date, the main uses of hydrogen are in the petrochemical and chemical industry, in oil refineries and in obtaining ammonia; although it is also used in the metallurgical, electronics and aerospace industries. At present hydrogen is also being used as fuel in fuel cell vehicles as well as in stationary applications. This hydrogen is obtained mainly from fossil resources, such as through the process of reforming natural gas, and to a lesser extent, through the process of electrolysis of water, separating the molecule from water into hydrogen and oxygen through a contribution of energy electric.