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"Green" hydrogen, bringing autonomous local régions far closer

Hydrogen produced by electrolysing water using renewable energy allows for the storage and use of excess electricity, among other things. This green hydrogen can also be used to decarbonise manufacturing processes and power zero-emissions cars. Let’s learn more about it...

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An essential element for storing renewable energie

Hydrogen is the lightest and most basic element in the universe. It’s made up of a single proton and a single electron. Hydrogen is also the most abundant element in the universe: it accounts for 75% of its mass and more than 90% of the number of atoms. However, hydrogen (H2) molecules never come on their own and are always combined with another element, as with water (H2O) or methane (CH4). 95% of hydrogen - which is now mainly used in chemistry, refining and manufacturing - is produced from fossil fuels. Hydrogen can also be produced by electrolysing water. If the electricity used comes from a renewable source, you can then say that the hydrogen is “green”.

Moving towards a 100% decarbonised ecosystem

Clean and sustainable hydrogen can be used for a wide range of applications and can replace fossil fuels. It could be an exciting prospect for manufacturers looking to decarbonise their processes. It could also be used to fuel charging points for hydrogen-powered vehicles (such as cars, lorries, buses, fork lifts and boats), which don’t give off fine particles or CO2 and only emit water.
What’s more, the electricity produced by hydrogen-powered dual fuel cells meets multiple needs, such as providing electricity supplies for isolated areas and even providing emergency electricity for critical sites. Hydrogen can also be used as a way of storing renewable energy which has been produced locally. To put it simply, this solution can help sites looking to enjoy “energy autonomy” or so-called “off-grid” sites - i.e. sites not connected to the national electricity network - to operate autonomously.

The National Hydrogen Plan presented by the French Government on 1 June 2018 is an integral part of this approach. It sets out to stimulate the roll-out of captive hydrogen fleets and the production of decarbonised hydrogen. “Hydrogen may become one of the cornerstones of a carbon-neutral energy model. This molecule, which contains a huge amount of energy, will become essential when you consider its wide-ranging properties: it can help you to store electricity, power cars, recycle CO2, make manufacturing processes cleaner and so on. Nicolas Hulot, former Minister of Ecological and Solidarity Transition.

Green transport

Hydrogen-powered transport is growing rapidly. Hydrogen-powered vehicles and charging points are popping up everywhere in cities and towns. There should be 100 charging points in the French network by 2020 and 500-600 by 2030. The growth of the hybrid hydrogen/electric vehicle sector is still in its very early days. However, this sector, which is particularly important for some types of vehicles (such as buses, taxis and delivery vehicles), in response to growing requirements on air pollution, is something that you can get behind. When used as a fuel, hydrogen can help produce electricity with the help of on-board hydrogen batteries. 

As a result, it’s a supplementary energy source both for vehicles with gas-powered internal combustion engines (such as buses and refuse collection trucks) and for electric vehicles. As a result, hybrid cars powered by electricity and hydrogen can charge their batteries while on the move. Using hydrogen extends how far electrical vehicles can run by up to 500 kilometres per charge. What’s more, the charging time is reduced from 8 hours for electrical charging to 5 minutes for hydrogen charging. But that’s not all! The hydrogen used therefore does not create pollutant emissions or noise pollution. The National Hydrogen Plan aims to accelerate the growth of the hydrogen sector in France and therefore intends to promote the widespread installation of electrolysers and the roll-out of a fleet of hydrogen-powered vehicles, setting a target of 5,000 light-duty vehicles and 200 heavy-duty vehicles by 2023, and up to ten times more by 2028.

More autonomous regions and buildings

As has already been mentioned, renewable energies are an effective solution to our current energy and environmental challenges. However, as they are intermittent, this can sometimes make distributing them difficult. “Power to Gas” technology can therefore help to store excess renewable energies by transforming them into hydrogen using water electrolysis. The hydrogen produced can then be stored, injected into the natural gas network, provide heat in cities and towns and be converted into electricity using fuel cells. As a result, hydrogen can help provide consumers with energy from renewable sources throughout the year and during peak periods in particular. As hydrogen can be produced, stored and used locally, this will encourage local communities and economic operators to develop hydrogen projects which aim to support the growth of wind power, solar power, biomass fuels and green transport.


Hydrogen is a gas traditionally used in the oil industry, the pharmaceutical industry, the chemical industry and the electronics industry. It provides multiple effective solutions for manufacturing parts, storing energy and transporting gases. For example, in the glass industry, it can help you to manufacture less polluting and more eco-friendly flat screens. So, what’s the benefit? You can use energy which has been produced locally, meaning that there are no transport costs and the environmental footprint is low. This solution could be extended to isolated sites (such as islands and areas located far from electrical networks) in particular.

The most recent example of decarbonisation has been the decarbonisation of some manufacturing processes which consume huge amounts of hydrogen, such as manufacturing ammonia or refining. As a matter of fact, the grey hydrogen used by these industries comes from cracking natural gas, which is a production process that emits huge amounts of CO2. For every kilogram of hydrogen that you produce, you emit 10 kilograms of CO2 using this method. 

This market offers great potential for development: 85% of the 60 million tons of hydrogen produced in the world in 2013 are used for producing ammonia and petrochemicals. Replacing grey hydrogen with renewable hydrogen would therefore help to significantly decrease CO2 emissions. 

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