Ah, yes. California. Where large swathes of costal areas hover between 60ºF and 80ºF. We are talking about Nevada the weather of locality matters and where it can be supremely hot.
You posted the Texas grid, I posted the California grid. Here's the NW grid which includes Nevada. Same thing, demand peaks around 6PM when people get home and turn on their houses.
I'm not sure that follows as the biggest driver. 4 PM is nearly as high as as 6 PM. You would expect a big jump at 5 PM, but the biggest jump is from noon to 2 PM. Just looking at today's temperatures on my front porch in Reno, it was 93°F at 2 PM, it peaked at 95°F at 3:30 PM, and it didn't fall back down to 93°F until 5 PM. Some of that sustained power usage probably is people getting home, but a lot of it is A/C.
https://www.eia.gov/electricity/gridmonitor/expanded-view/el...