> In many other places, you have to store for much longer term.
Yeah, that doesn't make sense. Overbuild and interconnect rather.
You can't do things like store summer solar energy for the winter. But there are plenty of places in the US where the sun is nearly always shining. If you can share that energy across the county you're in good shape. Likewise with the wind.
Again it helps you have solid baseload power. It's just nuclear is so expensive and takes so long to build that you can build twice the capacity in solar and wind plus a battery, plus a gas plant for a backup in less time and for a similar price.