Current battery technology is not up to what you are talking about. No one can come up with a price because we don't have the technology to store that much offline energy to handle the variability. Anyone who says we do -right now- is lying to you. We would need a factor of 100X energy storage density to what we have right now to even be close.
people who end up on opposite sides of this argument are usually talking about two different things:
1) Do we build exactly enough solar to meet our average power needs but have to build several-month-long battery storage capacity to bring summer sun into the winter,
2) Or do we build enough surplus solar so that we can run 100% load for 24 hours on a cloudy winter solstice, and just need big enough batteries to get through the longest night of the year, and under every other circumstance just be wildly over-provisioned
#1 is probably impossible with current technology. But our solar installations already produce surplus power during the summer that we don't use ("curtailment"), even at today's prices. It doesn't seem out of the question that we'd just build much more absurd extra solar to make up for our lack of storage. And then maybe we'd find a use for the excess summer electricity, like desalination or hydrogen production or bitcoin mining. It's technically possible, but it does increase costs - twice as expensive? three times? That might still be economically viable, if solar costs continue to fall or if the cost of natural gas spikes upward
