@qrnef,
I’m guessing that every kWh of energy you put back on the grid may have 5-10% losses as it get’s shipped someplace else, but not the 3x factor. And parts of the grid that are seeing upsurges in local renewable/low carbon are finding ways of valuing the energy you put back on the grid based on the immediate market and demand, which incents home producers to either do home demand shifting or battery storage. Sure, the grid operators have to have surplus capacity to handle weather related variations, but over the long run, solar and the renewables are statistically predictable, so the over-capacity doesn’t have to be 100% of the renewables.