You mention renewables and especially solar as a contributing factor to these negative prices when combined with capacity constraints. Can you explain how this works?

A PV installation can easily start and stop production as long as the sun is shining, right? Then it seems like PV producers should bid to produce as much as possible whenever the price is positive, and not produce anything whenever the price is negative. Is this how they operate, and if so, how does this contribute to negative prices and not just to bringing the price towards 0?