Texas power prices soar 20,000% as brutal heat wave sets off emergency

What you're describing is a pump and dump scheme. In any market where there is low volume, either in terms of units or value, it is possible that a wealthy individual buys a large enough share of the available item to make the price jump up a bunch. Then when other people buy to get in on the next bitcoin/NFT/GME craze, often motivated by person A, that first person can then sell to the next wave.

What is weird about the power grid is that A) electricity has to be used at the time of purchase so you couldn't resell it and B) there are often power plants specifically for spikes in demand (called peaker plants) that rely on those moments to jump in and produce to make their profit, keeping things under control. However if you're the Texas grid, which is isolated from any other electric grid, you can just ignore obvious signs that more power is needed and everytime demand spikes you make a bunch of profit and super promise you'll fix it for the next time

Contrary to what clickbait articles lead you to believe these spikes are incredibly brief. https://www.ercot.com/gridmktinfo/dashboards/systemwideprices

I’m really not sure how else an electrical grid is supposed to artificially encourage lowering demand than to fluctuate pricing. Lots of new appliances now can connect to the grid and shut themselves down temporarily when costs are high, this is an opt-in system that without pricing tied to it most people would ignore. If you need to use electricity at high demand time it had better be important.

And yes I realize in an ideal world every electrical grid would be 10,000% oversized and be able to handle infinite demand. That is unfortunately not the world we live in.