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You got me thinking, so I looked for some numbers.

Hydrogen has a specific energy of 120 MJ/kg, while Kerosine has 46 MJ/kg. According to the abstract of the paper being discussed here, the new material has a deliverable capacity of 14% by weight, corresponding to about 17 MJ/kg - only a bit better than 1/3 that of kerosine, but considerably better than lithium ion batteries, which apparently achieve less than 1 MJ/kg, while the best-performing lithium-sulfur batteries are at about 1.8 MJ/kg.

In addition, we must deal with this material only losing 14% of its weight as its hydrogen is used up, while kerosine loses all of its weight - a combustion-powered airplane becomes more efficient as its fuel is consumed.

Furthermore, to get that 14% deliverable capacity, you have to start with it at 100 bar, so the tank containing it will have a substantial weight.

So we have progress here, but not yet a substitute for liquid hydrocarbons.




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