Comments by "John Burns" (@johnburns4017) on "Revisiting the Supercapacitor - The Wait for Graphene is Over" video.

@matthewhuszarik4173 They explained that because of fast charge and discharge a smaller size is feasible in real life usage in many applications. Chemical batteries charge and discharge slowly, which loses energy along the way. Brake regen only claws back about 20-20% of electricity generated by the brakes. That can be on the 90% plus range. So taking electricity in and out of supercaps quickly reduces the need for larger storage in many applications. If greater storage is needed then a mixture of the two can make matters better - hence super-batteries. Long runs of cable reduces voltage, so cables have to be heavier. Supercaps can also reduce the need for heavy cables in long runs as the supercap storage in some appliances will ensure the voltage on start up, due to voltage drop on startup. And less gives drag on the grid.
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@sequoiahughes8536 The Prius was to have supercaps in 1997. They dropped it at the 11th hour.
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@UndecidedMF There was hope it would replace steel beams, but has not. It can have longer spans which must save costs, in only having load bearing walls in the perimeter of buildings. Its light weight means less substantial foundations. All this saves costs and time.
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This is just the beginning. The energy storage of graphene supercaps should improve. It could be to the point chemical batteries will be only for large scale applications. The application for hybrid electric trains, that can run onto non-electrified lines for 20 miles or so, looks good. Graphene may ensure this so-called hydrogen revolution will be still born.
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