I do think we need multiple tactics:

• Local (national) surplus energy stored also locally (home battery, chargings cars, powering local industry from renewables at moments it isn't needed elsewhere), so all kinds of buffers. To also use it within the same country at other moments.

• Diversify solar wind and thermal etc

• Exchange cross-borders despite geopolitical risc. Countries with more sun hours or more steady wind or abundant geothermal sources or more hydro ... could export their surplus or capacity but also import.

For solar: if storage exceeds need, the daytime countries at any moment should power the nighttime countries, but only to balance local smart grids I think?