Not quite true. If you over-build solar by a factor of 3 (above what you'd expect from an energy-only basis), then you can convert it into a 100% constant outp

Not quite true. If you over-build solar by a factor of 3 (above what you'd expect from an energy-only basis), then you can convert it into a 100% constant output baseload plant using about 50 hours of storage, based on a year of hourly sun data for a single site I found. You don't try to store seasonal energy, you over-size the solar panels so there's significant energy production even on cloudy winter days. Costs less than you might think, considering the spot price for solar cells is like 10 cents per Watt right now (20 cents for panels). Works in the continental US. Doesn't work in northern Europe because the winter days are too short (too high latitude).