Renewable (or green) hydrogen is hydrogen produced using renewable energy sources, such as solar, wind or hydroelectric power. The most common method of producing it is electrolysis of water, where electricity from renewable sources breaks down water into hydrogen and oxygen, with no carbon dioxide (CO₂) emissions.
Hydrogen
Hydrogen is the most abundant element in the universe, making up about 75% of its elemental mass. However, it is mostly found in combination with other elements, such as oxygen in water (H2O) or carbon in hydrocarbons.
Although hydrogen is colourless, it is classified into colours depending on how it is produced. The choice of the most appropriate method of hydrogen production depends on many factors, such as the availability of raw materials, infrastructure, financial resources, and environmental considerations. Continued research and development in this area is expected to provide even more efficient and cleaner methods in the future, making hydrogen a central element in the transition to a sustainable energy economy.
The main categories of hydrogen are
Green Hydrogen
Green (or renewable) hydrogen is produced using renewable energy for the electrolytic decomposition of water (H2O) into hydrogen and oxygen.
Grey Hydrogen
Most of the hydrogen produced today is 'grey' and is created by splitting natural gas into H2 and CO2 (Steam Methane Reforming - SMR), with the CO2 being released into the atmosphere.
Blue Hydrogen
Blue hydrogen uses the same production process as grey hydrogen, but the CO2 is captured and stored.
Brown Hydrogen
Brown hydrogen is produced using coal or lignite and has the largest environmental
footprint.
