Or just fill debts. Overclock every air conditioner freezer and industrial coolant system for those hours, store that not-heat. Do cpu intensive processes, time industrial machinery to be active during those hours, Sure, desalination, but pumped hydro(even just on a residential scale, more water towers, dammit!) or... Anything.
OR we could just decline to build them because they're... Sometimes too good to make a profit off of?
hell not even pumped hydro, with enough water towers you can just time refill of the towers to be on peak demand, though pumped hydro would also be another option
Or worst case, power some down. Excess electricity that can’t be used is a problem, it’s just that while solar may not be the easiest energy source to fix that problem with, it’s probably the second easiest behind wind. You can literally put retractable awnings over solar panels if you need to
Yes we need more long time energy storage. It helps to balance the energy grid and it helps for days when not enough energy is produced. Batteries aren't really the answer, but pumping water uphill might be.
Many places actually do pump water uphill into reservoir lakes for hydroelectric dams. In that case it is a form of energy storage, a literal water battery.
Unfortunately, it's not always a feasible option. For instance, in the great planes there's not much of an uphill to pump the water to.
I've seen some interesting ideas from Low Tech Magazine - one that I found particularly interesting was flywheel energy storage. Take a heavy disk or drum and spin it up with excess electricity, then discharge the spin from the battery when the Sun goes down.