Hydrogen production processes

The impact that hydrogen will have on decarbonization and its role in the energy transition will depend on how it is produced. In fact, according to the different production processes, hydrogen will be classified as follows:

• Grey hydrogen - produced from fossil fuels
• Blue hydrogen - produced from fossil fuels with capture, utilization and storage of carbon dioxide emitted
• Green hydrogen - produced from renewable energies

From grey to green hydrogen

In order to meet the targets defined for the EU 2050 strategy one of the most important challenges regarding decarbonization is the transition from grey to green hydrogen production. Green hydrogen is produced from renewable energy sources such as wind and solar, following the process of electrolysis, through which, thanks to electricity, water molecules are split into molecules of oxygen and hydrogen.

When we consider that the Dutch industrial sector alone generates 800,000 tons of hydrogen using Steam Methane Reforming (SMR) technology, it is clear that such production is functional and valuable within the hydrogen supply chain. However, its generation, as well as the potential capture and storage of CO2 emitted in production, are processes to be re-evaluated in the path of decarbonization.

What are the potentials of green hydrogen?

Green hydrogen, although now representing only 5% of total production, has a key role in the energy transition of our economy, because in its various uses and during its life cycle it does not generate CO₂ emissions.

According to the report published by IRENA, green hydrogen could play a significant role in decarbonizingspecific sectors of the economy such as energy-intensive industries, the chemical and commercial transportation sectors, as well as aviation and shipping, which are still highly polluting.

In addition, both electrolysers (the plants that, using electricity, break down water molecules into hydrogen and oxygen) and large fuel cells(harnessing electricity generated from renewables and stored hydrogen), could add flexibility to the supply and demand side of energy, facilitating the penetration of more wind and photovoltaics into the grid.

Although renewable energy production has the potential to deliver many benefits, the use of sustainable energy sources such as wind and solar still see significant challenges. For example, their power generation cannot always be used to meet society's fluctuating electricity demands, and with supply and demand not always in balance, new storage solutions are required.