Here’s a 2022 renewable energy accomplishment (it took 14 years to build, and came online in mid 2022) that is an exemplar for long term storage…

This pumped hydro facility can store 20 GWh of power and can release at 900 MW. They claim 80% round trip efficiency, and can reverse direction in 10 minutes…

Awesome!

https://en.m.wikipedia.org/wiki/Nant_de_Drance_Hydropower_Plant