Making France the leader in carbon-free hydrogen: this is the government's ambition announced in 2020 with the launch of the national strategy for the development of carbon-free hydrogen.

It was reaffirmed in 2022 as part of the France 2030 investment plan. 9.1 billion euros in public aid were approved and the first ten projects selected to create a hydrogen sector in France.

But why is France betting on hydrogen? What is hydrogen and what are its uses? Is it a promising path to a sustainable future?

What are the challenges to be met for hydrogen to assert itself as an energy of the future? SirEnergies takes stock.

What is hydrogen?

Hydrogen is not an energy source. It is a energy vector, in the same way as electricity, produced from natural resources.

What is hydrogen?

Hydrogen is a chemical element, very abundant in the universe. Without him, the Soleil and stars would not exist. It is their main component.

On the other hand, on Earth, it is Very little present in the natural state, except for a few unexploitable underwater fields. Clues ofwhite hydrogen However, pure ones would have been found in several parts of the world, including France. Their exploitation potential has yet to be proven.

Where is hydrogen found?

Hydrogen is a component of many chemical elements. It is present in thewater. It is composed of two hydrogen atoms for one oxygen atom, hence the famous formula H2O. It is also found in methane, a combination of four hydrogen atoms and one carbon atom (CH4), or in the hydrocarbons (CH).

Hydrogen also makes up nearly 10% of the human body. More generally, all living animal and plant organisms are partly made up of hydrogen, making biomass an inexhaustible potential source of hydrogen.

How is hydrogen produced?

Hydrogen is extracted from water, hydrocarbons, or biomass by chemical processes aimed at separating hydrogen atoms from other atoms.

Very polluting, the production of hydrogen is its Achilles heel. 96% of hydrogen comes from fossil resources, mainly gas (48%), oil (30%) and coal (18%).

In addition, production techniques such as the steam reforming of natural gas or the gasification of coal emit significant quantities of CO₂. It is estimated that on average 1 kg of hydrogen produced releases between 10 and 15 kg of CO₂. That's why it's nicknamed” grey hydrogen ”.

Less polluting, electrolysis consists in extracting hydrogen from water by separating hydrogen and oxygen atoms. The disadvantage: it requires a lot of electricity, most often from fossil fuels...

How is hydrogen stored?

Hydrogen is a highly volatile and highly flammable gas. If its storage is today well controlled, zero risk does not exist.

The storage in gaseous form is the most popular. However, the low energy density of hydrogen requires the use of high pressures to reduce storage volumes. TO 700 bars, the compression is optimal. This poses several disadvantages: the use of robust and durable materials, strict control of the tanks and the cooling of hydrogen to avoid overheating.

Storing hydrogen in liquid form at very low pressure is the ideal solution for reducing volumes. However, this process requires temperatures below −253°C and the slightest leak is synonymous with explosion. This is why it is reserved for very specific uses such as space propulsion.

An innovation could well offer the perfect alternative: the hydride storage. This consists of storing hydrogen in a solid material such as magnesium. In France, research is carried out by two teams, finalists of the 2023 European Inventor Award.

How is hydrogen transported?

Hydrogen is Relatively easy to transport. It is transported in compressed form via pipelines. While China is a pioneer in the field, a European pipeline project of hydrogen connecting Spain and Germany via France should be completed in 2030.

Today, the preferred transport solution remains the sea or road transport, via compressed hydrogen tube trailers.

What are the uses of hydrogen today?

Discovered in the 19th century, hydrogen has seen its uses multiply in recent years. Powerful, inexhaustible and non-toxic, it offers a wide range of possibilities, ranging from industry to mobility, including electricity storage.

Uses of hydrogen in industry

The industry remains the main consumer of the 900,000 tons of hydrogen produced annually in France. They are used in particular for the production of ammonia, methanol or nitrogen fertilizers, for the manufacture of steel and cement or for the refining of petroleum products, fuels and biofuels.

The carbon footprint of these uses is very high. On the one hand, the gray hydrogen exploited is very carbonaceous; on the other hand, high quantities of greenhouse gases are emitted by these industrial processes.

Decarbonizing the industry is a priority for the energy transition. It is based on two levers: green hydrogen And the Process of CO₂ capture.

The uses of hydrogen in mobility

Absence of CO₂ emissions and fine particles, power three times greater than gasoline, reduced recharging times: hydrogen is often presented as a future-proof solution for clean mobility. However, the hydrogen-powered car is struggling to find its place on the market, in the face of electric vehicle. Its highly flammable nature and the fuel cell complicate vehicle manufacturing.

On the other hand, hydrogen is a solution adapted to heavy transport, the most CO₂ emitters and difficult to decarbonize. It meets their needs for high power and/or autonomy. In France, the supply of hydrogen is encouraged for heavy goods vehicles and regional trains. SNCF announces the first hydrogen-powered TER trains in stations in 2025.

In The aviation sector , the technologies are not mature. However, there is no shortage of ideas between the manufacture of synthetic fuels from hydrogen, engines powered by hydrogen propulsion or electric motors powered by electricity from hydrogen.

However, the airline industry remains cautious. The storage volumes required for hydrogen are questionable. Tourism aviation could pave the way. A first French prototype equipped with a fuel cell Hydrogen is announced for 2026.

The maritime sector is one step ahead of aviation. The first boats sailing with e-methanol (produced from hydrogen and CO₂), or e-ammonia (a mixture of hydrogen and nitrogen), should go to sea by 2025. For its part, the first autonomous hydrogen vessel Energy Observer is continuing its observations.

The uses of hydrogen in electricity storage

If there is one field where hydrogen seems to be an essential solution for the future, it is that of electricity storage. It offers a relevant response to the intermittency of renewable energies and to the problem of electricity storage.

The principle? Store surplus renewable electricity production in the form of hydrogen via electrolysis.

During peak consumption, hydrogen can be reinjected into public networks in two forms: either in the form of electricity after transformation via a fuel cell, or directly in the form of hydrogen into the gas network.

Hydrogen: a promising path to a sustainable energy future?

Hydrogen, The energy of the future ? This is what many experts say. In France, it is clearly designated as a priority axis to achieve carbon neutrality in 2050. The only downside is the carbon footprint of its production, which reduces its environmental benefits..

A priority: decarbonizing hydrogen production

To offer a promising path to a sustainable energy future, hydrogen production must be decarbonized.

All hopes are focused on theelectrolysis using low-carbon electricity from renewable sources or nuclear.

According to ADEME, thanks to nuclear power, the electrolysis of water emits four times less CO₂ than the steam reforming of natural gas. However, its production costs are three to six times higher. Reducing these costs is one of the keys to industrializing low-carbon electrolysis.

Hydrothermal methanization or gasification are also presented as low-carbon hydrogen production solutions. The principle: generate a synthesis gas composed of carbon monoxide and hydrogen from fermentable waste. The carbon balance is considered neutral, because biomass emits in its natural state the same level of carbon dioxide as that generated by these transformation processes.

If we created hydrogen from microalgae ? This is the idea pursued by several teams of researchers around the world. It is inspired by photosynthesis. The idea: use the sun to separate oxygen and hydrogen from water.

Towards a low-carbon hydrogen Europe?

If France wants to be a pioneer in carbon-free hydrogen, the whole of Europe is committed.

One important project of common European interest (IPIEC) is now committed to supporting research, development and the first industrial deployment of technologies related to carbon-free hydrogen.

Ten projects of the 41 selected are French. The ambition: deploy up to 6.5 GW of electrolysis capacity to produce more than 600,000 tons of low-carbon hydrogen each year. Concretely, this should result in the construction in France of four gigafactories of electrolysers, hydrogen tanks, fuel cells for sustainable mobility, hydrogen trains and the materials necessary for the production of this equipment.

Hydrogen is an energy of the future. Already in 2019, The International Energy Agency affirmed it. Five years later, the enormous potential of hydrogen has been proven. It will undoubtedly be an essential component of the energy transition and energy mix of tomorrow.

But while the path has been brightened thanks to technological progress, it is still full of pitfalls. The main challenge? Succeed in decarbonizing its production at reduced costs.

Read on with this article: Can we really do without oil?