What is hydrogen?

By ENGIE - 08 October 2021 - 11:36

Hydrogen: the key to tomorrow’s challenges

It’s no mystery - one of the major challenges for the future of our civilisation lies in energy. Its accessibility and use are at the heart of ecological and even geopolitical debates. Indeed, the world’s population continues to increase, and despite efforts to reduce our energy consumption, our energy needs continue to grow. As such, it is vital to continue optimising the energy mix and to consider all options, in particular abundant, sustainable, clean and accessible alternative energy sources. Although it cannot be considered a “new” energy since it has been used since the 19th century, hydrogen, with its many uses, nevertheless seems to be able to respond to many problems.
Allow us to introduce a molecule whose most common source on Earth is water!


What is hydrogen?

Did you know? Hydrogen is the sun’s main component and is also what allows stars to form! Although it is the most abundant element in the universe, it is very rarely found in its natural state on earth.


Hydrogen (H) is a very light gas with the chemical formula H2. It is highly flammable, odourless, colourless, non-toxic and non-corrosive. In its natural state, it is generally combined with other atoms: it is notably found in water (H2O), oil (HC) and natural gas (CH4). In order to separate hydrogen from compounds, several chemical processes exist, such as: thermochemical or photochemical decomposition, steam reforming, pyrolysis of biomass or electrolysis of water.


Hydrogen has been used since the 19th century to power city lighting networks and to propel the Ariane rocket. In industry, it has been used for decades as a raw material for the production of ammonia and methanol, and for refining petroleum products, fuels and biofuels.


>> Five reasons why hydrogen will speed up the transition to carbon neutrality <<


Today, worldwide consumption of hydrogen amounts to 74 million tonnes, which represents less than 2% of global energy consumption. Thanks to the advent of hydrogen fuel cells, hydrogen becomes an energy carrier and offers a wide range of uses, such as energy storage, electrical supply for buildings and vehicle powering.


The ecological transition has propelled hydrogen to the forefront of the sector where it is making a strong impact in its renewable form, driven by the favourable stances taken by the government. In May 2016, the “Territoires Hydrogènes” tender was launched, resulting in the approval of 39 projects, and very recently, a hydrogen deployment plan was announced by Nicolas Hulot, Minister of State, Minister of Ecological and Solidarity Transition. The plan sets out to create a carbon-free channel and develop storage capacities and zero-emission solutions for transport. It can no longer be ignored - hydrogen is the future!


Although renewable energies are essential drivers of the energy transition, they have the disadvantage of being intermittent and of sometimes producing more electricity than the network requires. In steps hydrogen, providing an excellent storage and on-demand redistribution solution.