Demystifying science | Green hydrogen in Nunavik?

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There is precisely a project of this kind in Canada, in which researchers from the University of Quebec at Trois-Rivières (UQTR) are participating.

“I have just started a project on the subject with the University of Victoria,” explains Bruno Pollet, holder of the Canada Research Chair on the production of green hydrogen at UQTR.

To produce hydrogen with seawater, it must first be purified, desalinated and removed all impurities to avoid damaging the machines used to produce hydrogen. This explains why sites with low salinity are preferable. Mr. Pollet is also working on technology to produce hydrogen directly from salt water.

In Hudson Bay, salinity can drop below 30 g/L. In the North Atlantic, it can exceed 35 g/L.

The advantage of using sea water is to avoid disturbing waterways. Offshore production also benefits from stronger offshore wind, which facilitates the production of renewable electricity, essential for hydrogen to be green.

There are similar projects all over the world. In France, two firms, Elogen and Lhyfe, have invested in this sector. Last summer, Lhyfe tested a pilot unit for producing hydrogen from offshore wind energy, near Brittany. Elogen announced last summer a partnership with a Dutch producer of offshore wind turbines, for a pilot project planned for 2025. A German-Norwegian project plans the construction of gas pipelines from the Scandinavian country to the country of Goethe, to transport there starting from normal natural gas, then “blue” hydrogen produced from natural gas and offshore wind turbines, and finally green hydrogen produced from seawater.

The European Union also has a project called “Offshore Hydrogen Production in Europe”, or HOPE, in which an American firm, Plug Power, among others, is participating.

“Saudi Arabia has projects in this direction, but with solar energy and sea water,” says Mr. Pollet.

Canada is, however, well placed, in particular because of an Ontario firm, Hydrogen Optimized, founded by a family active in the field of hydrogen production by water electrolysis for more than a century, the Stuart family, believes Mr. Pollet.

What are the challenges to be expected in the longer term? “Eventually, we could find an outlet for the elements that will have to be removed from seawater to produce hydrogen, for example chlorine,” says Mr. Pollet.

As one of Canada’s goals is to provide clean drinking water to isolated indigenous communities, why not start now with water desalination technologies used in the Middle East, including Saudi Arabia and Israel? “It would certainly be possible, especially since there have been many advances to reduce energy consumption, for example polymeric membranes,” says Mr. Pollet.

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A previous version of this text incorrectly used the unit mg/L rather than g/L for seawater salinity.