That could be, though it's likely to be location specific. Areas with good hydroelectric might just have steady pricing -- solar during the day, hydro at night

That could be, though it's likely to be location specific. Areas with good hydroelectric might just have steady pricing -- solar during the day, hydro at night. EV owners often get reduced rates for charging at night; that could go away. That's an argument in favor of electrification of our major highways: if cars and trucks can charge while in motion, that shifts their time of maximum energy consuption to the daylight hours when people do most of their driving, and which better aligns with solar production. You might even have highways more-or-less directly powered by adjacent solar farms. Fortunately highways and solar farms both have reasons to exist in sparsely-populated countryside.