@MattMastodon @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis

A thought,
I wouldn't completely write methane, LPG , or any other petrochemical, off yet, as a seasonal storage medium.

They are a lot easier to store and transport than H2.
They can be produced from green H2 + captured CO2

https://en.wikipedia.org/wiki/Methanation

We have a lot of existing infrastructure which can use them.

That is of course If we can produce enough surplus Solar / Wind to make them.

https://www.power-technology.com/features/eth-zurich-fuel-air-and-sunlight/

@MattMastodon @Ardubal @Pampa @AlexisFR @Wirrvogel @Sodis

Batteries are great for short term storage (Hours to Days), but the further you are from the equator, the more you need seasonal storage.

Hydrogen possibly fits part of that, if it is produced by electrolysis when wind / solar are in surplus.

Problems are:
how to store it, it leaks through most storage containers, requires vast amounts of energy to liquify and
The round trip from Electricity via H2 to Electricity is very inefficient.