Solarpunk

I think these are wholesale prices, not residential.

Large consumers, like steel mills and refineries can adjust their consumption to smooth out fluctuations in base load power production.

For producers, it's often cheaper to give power away for free or pay consumers to take it rather than spin down a whole gas turbine/reactor/coal furnace. It wastes a shitload of energy to cold start one of those again and synch it with the grid.