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Hydrogen-powered planes almost ready for takeoff
(arstechnica.com)
This is a most excellent place for technology news and articles.
You'd need huge cryogenic tanks due to the volume density of hydrogen over kerosene. Good for rockets that you can jettison tanks from, but less so for planes. I just don't see it ever being practical for aviation over just creating our own hydrocarbons out of something else. Either catalyst based or otherwise. That's potentially carbon neutral as well.
Edit: my comment, but with numbers https://pubs.aip.org/physicstoday/article/74/9/11/928294/Hydrogen-as-an-aviation-fuel It's not a problem with how heavy the fuel would be or just how much space they'd take. It's how heavy the damn tanks would need to be and how much of the aircraft would be devoted to them on long distance flights.
It's no more of a problem than dealing with LPG, surely? Pressurise it for storage.
The difference is the 'L' in LPG. It turns liquid at a relatively low pressure and takes up much less space then. Hydrogen does not do that, so it has to be stored at a much, much higher pressure. For example, a medical oxygen bottle or a scuba tank has around 200 atm of pressure. For cars, hydrogen is usually stored at 700 atm. And the pressure inside an LPG tank is around 8 atm at room temperature.