Two weeks ago we discussed the viability of the hydrogen economy and what this new perspective entails for the future of rare metals investment. The purpose of this article will be to look more closely at two specific sectors that will likely be transformed by the hydrogen revolution.

With regards to hydrogen power, the most prevalent topic of discussion has been FCVs (fuel cell vehicles) and how these may supplant electric cars as a greener and more energy-efficient future transport solution.

However, hydrogen will not be used just for cars (which is why we can speak of a real shift towards a hydrogen economy).

Here are some technical specificities distinguishing two other key applications that are being proposed for hydrogen:


The “blended wing” hydrogen aircraft envisioned by Airbus


Hydrogen aircraft

How will a hydrogen plane be different from a hydrogen car?

A plane needs a great deal more energy, and pressurised hydrogen would not be sufficient. An aircraft would require liquid hydrogen (cryogenised at -253 ° C) stored in cooled and securely insulated spheres (particularly for trips lasting several hours). Gone will be the days of fuel being stored in the wings of planes, as we’ve had with kerosene. The technical challenges are numerous, but do not seem insurmountable thanks to the experience we’ve acquired from space travel which already uses liquid hydrogen, albeit for far shorter propulsion distances.

A fuel cell has a weight to power ratio that would be far too low to enable air travel (2 to 2.5 kw / kg). It must therefore be abandoned in favour of a turbojet which, instead of burning kerosene, will burn hydrogen. Current engine models, although not optimised for hydrogen, could realistically run on it. The air entering the turbine would also be cooled by the liquid hydrogen (which, conversely, would heat up before reaching the combustion chamber), and this would also increase the efficiency of the turbine. Finally, the combustion of hydrogen releases less heat than kerosene for any given power output, which would reduce the mechanical stress on the engine’s nickel superalloys and thus reduce maintenance costs. In such a scenario, the requirements for rare metals e.g. rhenium or ruthenium in nickel superalloys should remain the same as they are at present (notwithstanding generational changes).

Spherical tanks in the fuselage will mean rethinking the complete architecture of the aircraft. The blended wing concept presented by Airbus is a fitting example of this.

Airbus’ hydrogen plane should be able to carry 200 passengers over 2,000 miles by 2035. Meanwhile the fledgeling startup ZeroAvia, which has just received investment from backers including Jeff Bezos and Bill Gates, is stealing Airbus’ thunder by taking smaller, earlier steps: The company is planning to make a 19-seat hydrogen powered plane by 2023, with a view to making a 100-seat plane with a 1,000 mile range by 2030.


Hydrogen metallurgy

Hydrogen could be used in industries that produce high levels of CO2 such as steelmaking, metallurgy or cement production.

The steel industry today uses gas and coal as sources of energy, and also coal as a reducing agent for the removal of oxygen from iron ore, a process which generates very large quantities of CO2; it takes about 780 kilograms of coal to produce one ton of steel.


Metallurgy is currently one of our most CO2-emitting sectors.


Schematically speaking (since in reality the process involves different stages of reduction and smelting in a blast furnace, followed by refining of the cast iron) the equation goes: C + FeO => CO2 + Fe (plus a little carbon used to form the cast iron and then the steel).

The hydrogen steel industry would involve the replacement of coal with H2. We would then have: H2 + FeO => H2O + Fe

This type of steel industry would release water vapour rather than carbon dioxide in the production of iron which, when passed through electric furnaces, could be used to make steel.

The steel industry currently emits between 7% and 9% of global CO2 (compared with around 3% for the aviation sector).


A hydrogen economy: The outlook for rare metals

Hydrogen is a viable proposition with a broad economic range of applications, both in offering an efficient and stable alternative to electric potential energy as an energy storage and transport solution, and in terms of making our economies greener.

Rare metals will be central to the deployment of these new technologies.

But there is a fine line between a critical element being an in-demand commodity with a booming price, and its being a limiting factor that renders the wide deployment of a promising technology unviable in the long term.

This is why our critical dependency on countries such as China for the overwhelming share of critical rare metals mining will be a critical issue in years to come, as will be the recycling of hydrogen production metals such as ruthenium and iridium, and of renewable energy generation metals such as neodymium, silver, tin, indium and tellurium. Rare metals recycling is one of the key challenges that the Gallium Project, currently being developed by CDMR’s Vincent Donnen in association with a broad consortium of European industrial leaders, is aiming to respond to.

In the meantime, there is no doubt that if the hydrogen economy develops as numerous forecasts suggest, the aforementioned rare metals will be the investible commodities to watch. Expect to hear more about hydrogen energy metals investment over the coming months and years.

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