It's possible to store energy for full seasons, just not electricity.

It's been done with heat. Using cheap electricity in the summer to generate heat and store it in basalt. There's a small block of houses in The Netherlands that gets their heat that way: https://www.ecodorpboekel.nl/basaltaccu-is-opgebouwd-uit-duu...

There's more systems like this around the world, although they use different storage methods.

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

Berlin just uses a really big thermos can to store heat: https://group.vattenfall.com/de/newsroom/pressemitteilungen/...