Hydrogen: the energy of the future ?
Hydrogen exists everywhere on Earth and mainly in water (H2O). It is therefore rarely pure because it is often associated with other elements such as oxygen or carbon, so it must be dissociated to be able to exploit it.
New challenges : a greener production
It is already widely used today in industrial sectors (it is used for example to refine oil), but its production remains largely carbonaceous (830 million tons released in 2019, 2% of GHG emissions) because it comes from hydrocarbons (mainly gas and coal) which remain much more profitable.
There is another production process: the electrolysis of water which allows the H2O molecules to be broken down into dihydrogen (H2) and oxygen (O) by means of electricity. This technology is promising because it releases only water, which is therefore non-polluting. However, it must be emphasized that this technology requires a considerable amount of electricity already produced to be exploited. For it to be totally carbon neutral, it is therefore necessary for its production to come from renewable energy sources (Norway, for example, produces it thanks to its hydraulic and wind power). However, it is four times more expensive, and therefore represents only 1% of the world’s production.
Different uses of hydrogen :
The heat production : when hydrogen is burned, it generates very high temperatures that can be used to replace the use of resources that emit more CO2 (coal or gas) in industrial sectors. In Sweden, the HYBRIT project is implemented, a steel production process without greenhouse gas emissions (1 ton of steel is produced for only 25kg of CO2 emitted, the trend being 1850kg/ton).
The decarbonation of the transport sectors with the use of fuel cells : this sector raises major issues. The various experiments have shown that the efficiency for light vehicles is not optimal, so the use of batteries would be more interesting for these cases. Instead, the use of hydrogen has to be encouraged for heavy transport (rail, air, river transport…). The first hydrogen-powered TER is scheduled to come into service in France in 2025 and the Council for Aeronautics and Civil Research (Corac) has already released 1.5 billion euros of credits, part of which will be devoted to air research for 2035.
The energy production and storage : what is important to remember is that hydrogen is not an energy source in the strict sense of the word, but a vector, in the same way as electricity. Its considerable advantage is that it can be stored through the electrolysis of water. It is therefore essential to compensate for the intermittent nature of renewable energy. It would be the keystone of the energy transition. However, its storage has a few negative points : hydrogen needs to be liquefied or cooled at extremely low temperatures, and the infrastructures are expensive and require advanced technologies to be operated.
A new way of empowerment :
Today, hydrogen has become the resource to be mastered, and the entire world community is mobilizing ressources in that direction. Russia in particular, which has stated that it wants to be one of the main producers through the Strategic Energy Plan 2035, ratified on June 9 2020, and the project Hydrogen Energy Development in Russia for 2020-2024. Gazprom and Rosatom will be the two main producers, with the first hydrogen production units planned for 2024.
Hydrogène: l’énergie du futur ? – Osons comprendre
Hydrogène: « La France a de quoi rivaliser avec la Chine », Agnès Pannier Runacher. La Tribune, samedi 24 octobre 2020.