Some four million homes in Texas were left in the lurch without energy in the bitter cold—many for more than 50 hours—as Winter Storm Uri swept across the State of Texas, spreading record-low temperatures, a natural disaster and a state of emergency for all of us when Texas utilities were forced to service interrupt their customers at a time when power was needed the most.
The Electric Reliability Council of Texas (ERCOT) is responsible for overseeing the Texas electric grid for about 90 percent of the state, and KPUB is in the ERCOT territory. Our utility is subject to the ERCOT market issues that Governor Abbott has been pointedly criticizing and has vowed to improve.
ERCOT’s main job is to ensure the safety and reliability of the Texas’ electric grid. That means when the amount of electricity generated by power plants does not meet electric demand, or customers’ use of electricity, ERCOT directs utility companies to interrupt service to prevent complete loss of power for the entire grid.
Prior to the events our community experienced last week, ERCOT had initiated system-wide rotating outages just three times in the history of ERCOT (Dec. 22, 1989, April 17, 2006, Feb. 2, 2011). None of those were close to the length of this event. The ERCOT rotating outage event that we have experienced is one that is completely unprecedented.
ERCOT issues a statewide mandate for load reduction—each utility knows its share, and it’s up to those utilities to determine how to reduce that energy amount and when to rotate. In KPUB’s case, the Lower Colorado River Authority (LCRA) manages that load reduction for KPUB and a number of other small utilities like us in Central Texas. Our utility has no control over the length of the outages, the frequency of them and when or where they will occur.
Rotating outages occurred for entire substations within our community, staggered at different times and different areas to prevent major outages all at once. All substations are subject to emergency events and service interruptions unless they are powering one of our hospitals (Peterson, the VA or the State Hospital); those substations are never interrupted, unless the entire state grid were to lose power. If someone was a KPUB customer and did not experience a loss of power during this event, they are powered by a hospital substation or subject to other next-level emergency ERCOT events and additional major state-grid events.
In an ideal setting, the rotating outages would have happened in smaller time windows. However, due to the increased demand for electricity and the unprecedented amount of load being shed, it takes more outages with longer off times and shorter on times. A typical heat strip heater, like most customers have in the homes, will consume about three times more energy than an AC system would during the summertime. This added demand for electricity delays the process of being able to rotate outages in this emergency event.
Some KPUB customers experienced longer outages if failures occur during the restoration process. This was the case with a few of our substations during the rotating outages event. The number of operational challenges from Monday to Wednesday last week was equivalent to what we might normally see in a year.
Examples of these failures include loss of communications to substations resulting in an inability to turn breakers back on after a rolling outage (these occurred at our both our Harper Rd substation and Rim Rock substation throughout the events) and equipment malfunction (we had an LCRA breaker control failure at Sidney Baker North at the Stadium substation). These types of failures require LCRA and/or KPUB to dispatch personnel to manually restore power.
In addition, we also had a relatively small number of local outages caused by overloading and ice. Restoring these outages was challenging because of the travel, working conditions and rotating outages that were occurring. At the peak of the rotating outage events, approximately 76% of our service territory was without power.
KPUB Response Timeline
• 8:47 a.m.: The ERCOT issues an Emergency Conservation Notice, and cancels the warning at 1 p.m.;
• KPUB line crews respond to Central Texas Electric Cooperative’s (CTEC) request for mutual aid for help in restoring power in their service territory due to weather-related outages (Mountain Home area).
• 8:30 a.m.: ERCOT issues appeal to conserve energy, asking consumers and businesses to reduce their electricity use as much as possible Sunday, Feb. 14 through Tuesday, Feb. 16;
• 10:37 a.m.: KPUB issues Code Red alert to Kerr County Sheriff’s Office for public distribution and emails emergency alerts to customers and media at 11:28 a.m., asking them to conserve energy usage;
• 3:17 p.m.: ERCOT issues a watch for “a projected reserve capacity shortage with no market solution available;”
• 9 p.m.: KPUB reports an outage in the Comanche Trace area affecting approximately 300 customers.
• 12:15 a.m.: ERCOT issues Energy Emergency Alert (level 1) to conserve energy and asks for power conservation in Texas;
• 1:07 a.m.: ERCOT issues Energy Emergency Alert (level 2) to conserve energy (“There may be a need to implement rotating outages. ERCOT is urging consumers and businesses to reduce electricity usage.”);
• 1:20 a.m.: ERCOT issues Energy Emergency Alert (level 3), entering emergency conditions and initiated rotating outage orders for utilities. (Energy load shedding is required by utilities in order to restore and maintain grid system frequency.)
Rotating outages must now begin for forced service interruptions;
• 7:19 a.m.: KPUB reports 47 percent of its service territory (or 10,985 customers) is without power due primarily to rotating to outage events with smaller outages requiring physical crew repairs happening within its service area.
• 1:43 p.m.: KPUB reports 76 percent of its service territory (or 17,632 customers) is without power due primarily to rotating to outage events with smaller outages requiring physical crew repairs happening within its service area .
• 1:43 p.m.: KPUB reports 37 percent of its service territory (or 8,584 customers) is without power due primarily to rotating to outage events with smaller outages requiring physical crew repairs happening within its service area.
• 8:11 a.m.: ERCOT temporarily suspends Texas electric utility orders rotating outages at this time, but they advise that a significant amount of generation is still offline. It is possible that some level of rotating outages may be needed over the next couple of days to keep the grid stable, so this is all still subject to change. The Level 3 EEA event is not yet canceled;
• Smaller outages requiring physical crew repairs happening within its service area are still affecting customers;
• 2 p.m.: KPUB reports all outages restored in its service area.
• 8:36 a.m.: ERCOT announces they expect to come out of emergency conditions later that morning;
• 9 a.m.: ERCOT officially cancels the Level 3 EEA (energy emergency alert);
• KPUB begins electrical restoration efforts again to provide mutual aid in the CTEC service area Friday morning and continues throughout the weekend, and they are still currently helping CTEC in their service area this week.