The question is not about solar or not, it's about what amount makes sense in a given place at a given time.
Sunny places close to the equator can probably go 90%+ from solar + batteries. Somewhere like Europe will have a lower number, maybe more like 40/50%.
And there's still the big question of: what do we do when solar and wind and storage are not enough? Because the numbers above are averages, not constants.
Right now all the answers are unsatisfactory: do not match supply to demand, but there's only so much you can do before people can't afford to heat themselves, and it's not good for your industries. Use gas-powered plants, but we want a carbon free grid. Nuclear but it's very expensive. Massively overbuild renewables but it's also very expensive. Add transmissions to far away places where they have power: also very expensive, and an added dependency/geopolitical risk.
Sunny places close to the equator can probably go 90%+ from solar + batteries. Somewhere like Europe will have a lower number, maybe more like 40/50%.
And there's still the big question of: what do we do when solar and wind and storage are not enough? Because the numbers above are averages, not constants.
Right now all the answers are unsatisfactory: do not match supply to demand, but there's only so much you can do before people can't afford to heat themselves, and it's not good for your industries. Use gas-powered plants, but we want a carbon free grid. Nuclear but it's very expensive. Massively overbuild renewables but it's also very expensive. Add transmissions to far away places where they have power: also very expensive, and an added dependency/geopolitical risk.