Texas’ main power grid struggled to keep up with the demand for electricity Monday, prompting the operator to ask Texans to conserve power until Friday.
The conservation request comes at a time of heightened anxiety around electricity following the state’s catastrophic February power outages that left millions without electricity for days. The outages that were prompted by a severe winter storm may have killed as many as 700 people, according to an analysis of mortality data by Buzzfeed news.
The Electric Reliability Council of Texas said in a statement that a significant number of power plant outages combined with expected record use of electricity has resulted in tight grid conditions. Approximately 11,000 megawatts of generation is offline for repairs, or enough to power 2.2 million homes on a hot summer day.
Of the plants offline, about 8,000 megawatts of power, or more than 70% of the outages, are from thermal power sources, which in Texas are largely natural gas-fired power plants. That’s more than double what ERCOT usually sees offline for thermal generation maintenance during a summer day. Typically, only about 3,600 megawatts of thermal generation is offline this time of year.
“This is unusual for this early in the summer season,” said Woody Rickerson, ERCOT vice president of grid planning and operations, in a statement. He said the grid operator would conduct an analysis to determine why so many units are offline this week.
Maintenance outages are more common during the spring and fall as power plants prepare for the extreme heat in the summer or extreme cold in the winter.
Companies’ maintenance outage requests are “automatically accepted” if submitted 45 days in advance, ERCOT previously told the media in an April conference call. The grid operator may reject outage requests submitted with fewer than 45 days of notice. In April, ERCOT also asked residents to cut back power use due to a high number of plants offline for maintenance, some due to repairs necessary from damage during the February winter storm.
The high number of outages this week combined with expected record demand: The grid operator estimates demand for electricity could exceed 73,000 megawatts on Monday. The previous record for June was 69,100 megawatts in 2018.
“[Electricity demand] is really driven by temperatures, and right now it is 99 degrees in Dallas, 97 degrees in Austin, and 97 degrees in Houston,” said Joshua Rhodes, research associate at the Webber Energy Group at the University of Texas at Austin. He said at those high temperatures, people tend to crank up their air conditioning, which strains the grid. At the same time, he said, power plants have already had a rough year given the February outages that caused damage, which may be causing the high number of generation outages.
Power grids must keep supply and demand in balance at all times. When Texas’ grid falls below its safety margin of excess supply, the grid operator starts taking additional precautions to avoid blackouts. The first precaution is to ask the public to cut back electricity usage.
Following criticism that the grid operator did not consider severe enough scenarios in its planning, ERCOT outlined the most extreme calculations for this summer that it has ever considered. ERCOT warned in its summer assessment of power resources that a severe heat wave or drought combined with high demand for power could put the grid in jeopardy. (Texas is expected to have a hotter and drier summer than normal this year, according to an April climate outlook from the National Oceanic and Atmospheric Administration).
Texans can reduce electricity use by setting the thermostat to 78 degrees or higher; turning off lights and pool pumps; avoiding use of large appliances such as ovens, washing machines and dryers; and turning off or unplugging unused electric appliances.
