If we stop using fossil fuels to make chemicals and materials, we'll need vast quantities of electrolytic hydrogen. Ammonia production alone was about 175 million tonnes in 2016, requiring 31 million tonnes of hydrogen. At 50 kWh per kg of hydrogen, that would be roughly 177 GW of electrolyzer capacity working at a 100% duty cycle. Using hydrogen in place of coal for reducing iron ore would consume even more hydrogen.

https://en.wikipedia.org/wiki/Ammonia_production

Japan is interested in it as fuel, despite the well known drawbacks, because Japan has such limited domestic energy resources.

But the original article's project isn't stopping using fossil fuel. It's using fossil fuel to make hydrogen. This is just money laundering for carbon atoms.

You are correct. I originally thought that this was another article about this Australian hydrogen project, also targeting Japan (and other energy importers) but powered by renewables:

"Western Australia’s multi-gigawatt green hydrogen giant edges forward"

https://www.pv-tech.org/news/western-australian-renewables-h...

What if we lived in a world where EVs are ubiquitous and they are powered by lithium ion batteries charged by renewable energy and/or nuclear. Specialized plants can still exist in this scenario to provide hydrogen and even diesel for industrial processes. The existing gas and coal plants wouldn’t be used for powering the general population anymore and would become more specialized producers.

There's also been work on getting solar thermal to the point where heat alone could be used at input into an industrial process.

https://www.fastcompany.com/90477609/this-startup-uses-mirro...

>where lithium-ion batteries can do the job

Right, so for short-term grid storage and automotive applications.

How about long-term storage, chemical feedstocks, air & sea transport? Those are huge, and batteries aren't a good match. There's still a place for hydrogen, just maybe not where people initially thought it would be.

For air, hydrogen isn't that great either. The volumetric energy density isn't fantastic, and you need to store it in cylindrical tanks rather than just using the wings as tanks.

There are several projects to make smaller hydrogen planes, but I suppose larger planes will always need liquid hydrocarbons. Considering that the very smallest planes will probably be battery-electric, hydrogen may end being squeezed from both ends of the market in the long term.

For long distance sea transport, ammonia is a big competitor.

Fundamentally speaking, hydrogen is not a good fuel. It's hard to handle and not very energy dense (volumetrically). What's good about it, is that we have relatively efficient ways to make it from electricity, and to convert it back to electricity. But it's possible that methods to produce/use other fuels could be almost as efficient over time.

Hydrogen will be very important in the next 3+ decades, but I can see it being made irrelevant again over time, by better batteries at one end, and better ways of making/using hydrocarbon fuels on the other.

You need hydrogen to synthesize ammonia and hydrocarbons though. It might gradually become irrelevant as an end product, but increasing quantities will be produced and consumed close to production of steel, fuels, and other chemicals.