All these proposed strategies to live with variable storage only work for short term variability, in places close to the equator. In my country, there is an almost 10x difference on solar energy between Summer and Winter. While (domestic) energy usage doubles in the winter.

The only feasable 0 carbon options are to either install an absolutely massive amount of Hydrogen storage and conversion, to give up any hope of self-sufficiency and import all electricity during the winter from places on the other side of the world, or to use Nuclear.