Hydrogen-Powered Planes: Pie in the Sky?

[Vlad Kovalenko + 115]

Liquid hydrogen has to be kept at -253C. The tanks to contain it are not only heavier but four times the size of conventional fuel storage. Even the keenest advocates admit hydrogen will initially be limited to smaller, shorter-range aircraft.

https://www.ft.com/content/7099d84c-07b8-4970-b826-ac28b4e59841

[markslawson + 1,057]

Vlad - little point in linking an article behind a paywall. Better to copy a couple of key paragraphs and paste them in your post. As for the point, most of the material I've seen about making air travel green has been about buying carbon offsets. Otherwise, finding a viable way to cut emissions fort air travel is hard. One way to reduce emissions in air travel would be to ban activists from attending international meetings on emission reductions, but I don't think that is going to happen.    

[turbguy + 1,543]

On 3/16/2021 at 8:16 AM, Vlad Kovalenko said:

Liquid hydrogen has to be kept at -253C. The tanks to contain it are not only heavier but four times the size of conventional fuel storage. Even the keenest advocates admit hydrogen will initially be limited to smaller, shorter-range aircraft.

https://www.ft.com/content/7099d84c-07b8-4970-b826-ac28b4e59841

There's always the "Hindenburg" usage.  That's a LOT lighter.

[Piotr Berman + 82]

Perhaps hydrogen fuel for airplanes is possible.  I read that Novatek, now specializing in turning NG from Russian Arctic into LNG, wants to export hydrogen in the future.  The actual text says that it would be in the form of ammonia, which is like methane, except with nitrogen instead of a carbon.  That would suggest that it is easy to detach hydrogen atoms from a nitrogen atom and burn it.  Liquified ammonia is quite feasible to store, this is part of the premise of exporting hydrogen in this form.

Could ammonia be used to fuel "hydrogen airplanes"?

[Sebastian Meana + 278]

It makes more sense using hydrogen for planes, wether it comes from Electrolysis or from natural gas Pyrolysis

An Airbus A350-900ULR has a max take-off weight of 280 Tons, it uses 160 tons of jet fuel (5/9 of the weight) to fly 18000KM, but it would only use 30 tons of Hydrogen, in part because is 3 times more energy dense, and in part because that energy density allows a lower fuel payload, you need extra fuel to carry the weight of extra fuel

It also would improve efficiency, thrust and power benefits since Hydrogen produces more power per every KG of oxygen, and since water has a lower molecular mass and higher heat capacity than CO2 it makes a better working fluid for the turbine engines,

Having to store it is the hard part, LH2 needs to be stored in fancy CFRP tanks with multilayered  aerogel core insulation, but you don't need it to be liquid for more than 30 hours

For the same price per MWh of energy Hydrogen planes would cost 1/5 less to operate than Kerosene planes without optimizing them

[footeab@yahoo.com + 2,190]

Is there such a thing as a hydrogen turbine which can last thousands of hours?  No. 

Hydrogen Fuel cells to electric fans?  No

Does Hydrogen's energy density matter?  No

Will there be a hydrogen airplane?  No. 

LNG on the other hand...

[-trance + 114]

Airship filled and fuelled by hydrogen gas maybe... It would just be really, really slow. Haha.