That happened early Tuesday, when ERCOT called on about 4,000 megawatts of battery storage to help meet the morning demand crunch. Those same batteries were charging up during the day to be ready for when the sun goes down and demand spikes again for the evening temperature drop.

Snow, sleet and freezing rain across Central and South Texas could bring down power lines, causing localized outages beginning Monday evening.

Another Arctic blast of freezing temperatures will test the ERCOT grid during this Martin Luther King Jr. holiday weekend and early next week.

The following chart rounds up the numbers of current power outages by county and by provider across southeast Texas.