The battle to avoid rolling blackouts in Texas' unrelenting hot weather as power demand reaches record levels has become a daily drama that can turn on a few degrees or the unexpected shutdown of one of the state's power-generating units.
Officials are hopeful the system will hold up without significant power outages for Texans.
But they acknowledge that with temperatures reaching nearly 110 in some places, the system will continue to dangerously ride on the cusp of capacity this week, and perhaps beyond.
Last Wednesday, ERCOT saw a record peak demand of 68,295 megawatts. It escaped having to resort to rotating residential power outages by shedding large industrial and commercial users through prior arrangements.
The demand on Monday was 66,581 megawatts.