Solar energy is not only intermittent, but also variable.
I have the minute by minute output plots of my neighbor's solar system and they vary quite a lot, especially during a partially clouded day, common in New England.
Solar provides expensive, variable, intermittent, i.e., junk energy, but not RELIABLE energy, and certainly not dispatachble energy.
In NE, solar CF about 0.14, cost about 20 c/kWh (with subsidies), average monthly DAY-TIME PEAK grid prices about 7 c/kWh, rarely exceeding 8 c/kWh.
Many solar installations within a distribution grid (Germany, California) will upset the local grid requiring battery systems to be installed as dampers to minimize disturbances.
This has nothing to do with storage of energy for later use.
Viable storage, other than hydro, has not yet been invented, and would take many billions and many years to deploy AFTER it has been invented.
Right now, it is snowing in NE and their is no wind. Where would the energy come from to power my computer to write this comment?
Conclusion: ALL other generators, staffed, fueled, kept in good working order, are required to provide energy when wind and solar are absent, PLUS to provide balancing when wind and solar ARE present!!!