COP26: What is green hydrogen? | NEWS
This is one of the subjects of COP26 and yet it is still unknown to the general public. The question of green hydrogen and its uses raises questions. Belgium has announced that it will even go so far as to import this "energy of the future" from Namibia.
Contrary to popular belief, hydrogen is not a totally green solution (and still far from it) for the future of industry and the automotive and air transport sector.
Because for now, hydrogen as an energy source is more gray than 100% green.
In question, the electrolysis necessary for its production proves to be very consuming of current. Explanations.
How is hydrogen produced?
Industrial hydrogen today is 95% made from fossil resources and mainly natural gas or gasified coal. A method used in particular in China and which releases a lot of carbon dioxide into the atmosphere. An element that remains the main cause of global warming. For one kilo of hydrogen produced, 10 kilos of CO2 are released. This is called “grey” hydrogen.
“Green” hydrogen, that is to say clean, consists in using the electrolysis of water. Concretely, the idea here is to pass electricity through water to dissociate the molecules of oxygen (O2) and those of hydrogen (H2), contained in H2O (water). A technique which then rejects no gram of CO2. However, for hydrogen to be 100% clean, so-called renewable electricity should also be used. This is where wind, solar, hydroelectric or biogas energy come into play. The African continent sees in this a new Eldorado for producing this hydrogen. The level of sunshine counts for a lot in its production if you opt for solar energy. Saudi Arabia and Namibia are positioning themselves in this niche.
A cost problem?
Presented to the public as a clean and potentially “inexhaustible” solution compared to the exploitation of fossil fuels whose reserves are drying up, green hydrogen must above all overcome a major obstacle: its production cost. Because if producing gray hydrogen for industry costs between 1.5 and 2.5 euros, depending on the initial price of natural gas, without counting the possible margins of producers and distributors, green hydrogen could cost twice as much dear.
“A kilo of H2, the equivalent of 6 liters of diesel, is worth around 10-12 euros”, recently explained to Agence France-Presse, the energy specialist Olivier Menu, responsible for the development of Hynamics, the subsidiary Hydrogen from the EDF group. The latter thinks he can lower this price to 7 euros within three to five years.
This is why research projects in this direction have multiplied in recent years. As part of the France 2030 program, the State plans in particular to build “two gigafactories of electrolyzers” to become “leader in green hydrogen” in 2030.