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A comment on Photocatalyst splits water into H and O2 at quantum efficiency near 100%. Parent comment

Re:Photocatalyst splits water into H and O2 at quantum effic... by ed25519FUUU on Saturday December 26, 2020 @12:31PM (#25544862)
Hydrogen has an energy density of 120 MJ/kg. Gasoline has an energy density of 46.4 MJ/kg. Lithium ion batteries at 2.5. They’re not even in the same ballpark.
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Re:Photocatalyst splits water into H and O2 at quantum effic... by yholio on Saturday December 26, 2020 @01:03PM (#25545124)
> Hydrogen has an energy density of 120 MJ/kg.

Divide that by 15 to get real world densities of compressed hydrogen composite storage tanks, you need a 104 Kg tank to store 7.5 Kg of hydrogen, for a total of 111.5 kg when full.

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Re:Photocatalyst splits water into H and O2 at quantum effic... by newacct583 on Saturday December 26, 2020 @12:46PM (#25544985)
Only aircraft care, though. Fuel weight in other applications is basically a non-issue except for really niche gadgets.
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