That isn't really related. Like I said, it's possible the temporary spikes in prices can make mining with fossil fuels profitable, but that is in the short term.

> If the power was literally not being used the cost would be negative - this is a real thing that happens.

Price only goes negative when there is too much energy produced, but downregulating production would be even more expensive. This is mostly a problem with wind energy combined with coal or nuclear plants. Otherwise you would downregulate production so you don't have to pay the penalty. Consuming this excess energy in a profitable manner would keep prices above zero.