As temperatures rise and more people crank up their air conditioning, Texans are likely to wonder if the state’s power grid is prepared to meet electric demand. Texas’ power grid operator asked residents to conserve energy 11 times last summer and twice during a January arctic blast.
Energy leaders face continued skepticism from Texans in the three-plus years after the deadly power outages during Winter Storm Uri, the dayslong freeze in February 2021.
Community Impact sat down with leaders from the Electric Reliability Council of Texas on May 21 to discuss how the grid has evolved to meet the needs of Texas’ rapidly growing population, what residents can expect this summer and the local response to the May 16 storm in Houston.
What you need to know
“The summer used to be a fairly simple season to manage,” ERCOT President and CEO Pablo Vegas said. “You would have your hottest part of the day at three, four or five o’clock, and as long as you had enough supply during those hours, you were in good shape and you could get through the summer.”
It’s not as simple today. ERCOT relies partially on solar power to meet high demand during the summer, resulting in a “rapidly declining energy source” as the sun sets, Vegas said.
“Oftentimes, wind picks up in the evenings in Texas, and so you have kind of this handoff from the solar power to the wind power,” Vegas said. “But that doesn’t happen every day.”
During periods of high demand with low wind and solar capacity, officials may call on Texans to voluntarily reduce their energy use for a few hours. For the first time since Winter Storm Uri, ERCOT briefly entered emergency operations Sept. 6 as power reserves dropped, although the grid operator said rotating power outages were not needed.
With the official start of summer less than a month away, Vegas said there are “more generating resources available this summer than we’ve ever had before,” which will help offset declining solar power in the evenings.
“We operate the grid with a conservative point of view on making sure there’s always enough committed generating resources to what we expect to happen over the next hour,” Vegas said. “And what that does, is it ensures that we have enough resources called up and ready to deliver, and we’re going to continue to operate the grid that way coming into the summer.”
Power plants and transmission facilities across the state have been upgraded to ensure they can withstand extreme temperatures, said Venkat Tirupati, ERCOT’s vice president of DevOps and Grid Transformation. Legislation passed in 2021 required energy providers to “weatherize” their facilities after some power plants shut down during Winter Storm Uri. ERCOT has inspected 2,117 weatherized facilities since December 2021, according to agency data.
Officials hope to avoid “[leaning] on consumer behavior” this summer, Vegas said.
“We’ll try to be as transparent, upfront and clear about why we’re asking for it and what we’re doing to try to mitigate that down the road,” Vegas said, referring to the event of a conservation request.
Also of note
ERCOT reached a record of 85,508 megawatts of electric demand on Aug. 10. This surpassed the previous year’s record by over 5,000 megawatts. One megawatt of energy can power about 250 homes during peak hours, according to ERCOT.
Last year was Texas’ hottest on record, and scientists say an increased frequency of 100-degree days and longer wildfire seasons are on the horizon.
“Summer of 2023 peak demand made Winter Storm Uri look really, really low, in terms of peak demand—it was a 7-8 gigawatt increase,” said Le Xie, an electrical and computer engineering professor at Texas A&M University. “So, the question is: What in the world can we do. .. to really push down that peak demand [this summer]?”
During peak summer demand periods, residential customers make up nearly 50% of the state’s electricity use, Xie said during ERCOT’s inaugural innovation summit May 21. Air conditioning alone is more than half of residential consumption on hot summer days.
Zooming in
Two tornadoes battered the Greater Houston area May 16, with winds surpassing 100 mph. At one point, nearly 40% of CenterPoint Energy customers were without power. Officials estimated power repairs would be “substantially complete” by the evening of May 22, Community Impact previously reported.
ERCOT does not own any power plants or operate power lines, which are the responsibility of local utility companies, such as CenterPoint. In general, power outages during extreme weather events are tied to local issues and unrelated to grid reliability.
“We’re like the air traffic controller of the electric grid. We operate the resources and make sure that the supply is always matching the demand,” Vegas said. “So when a storm comes through like that, it’s typically the transmission [and] distribution utility company who’s responsible for making sure that their infrastructure is as ready as possible to meet those impacts.”
In recent years, ERCOT and the Public Utility Commission of Texas have worked with state lawmakers to strengthen the power grid and local utility systems. The Texas Energy Fund, which was approved by voters in November, offers $7.2 billion in grants and low-interest loans for the construction and maintenance of “dispatchable” generation facilities, including natural gas, coal and nuclear plants.
“It’s impossible to prevent every single weather damage and impact, but I can tell you that the industry is working hard to do everything they can to do so,” Vegas said. “When there is a significant impact, they respond quickly; they focus on safety; they prioritize making sure that vulnerable customers and the highest-demand, critical type of customers are getting the power as soon as possible—hospitals, emergency services, things like that.”
Terms to know
ERCOT issues several types of notices to inform Texans about changes in grid conditions, including:
- Advance Action Notice: These notify energy providers that ERCOT may ask them to adjust or delay scheduled maintenance due to projected shortages of power reserves.
- Weather watch: These are typically issued 3-5 days before forecasted severe weather, high demand and potentially lower reserves. Grid conditions are expected to be normal during a weather watch.
- Conservation notice: These notices ask Texans to reduce their electricity, if safe to do so, during a specific time period when demand is high, such as a summer evening or a winter morning. This means there is the potential for a power grid emergency, although conservation typically helps ERCOT avoid emergency operations.
- Emergency alert Level 1: These are issued when power reserves drop below 2,500 megawatts and are not expected to recover within 30 minutes. During this time, ERCOT works with energy providers to access all available generation and obtain additional power from grids in other states.
- Emergency alert Level 2: This means power reserves have dropped below 2,000 megawatts and are not expected to recover within 30 minutes, or grid frequency is below 59.1 hertz. Due to low reserves and frequency Sept. 6, ERCOT skipped alert Level 1 and went directly to Level 2.
- Emergency alert Level 3: This is the most critical emergency period, when power reserves drop below 1,500 megawatts or frequency drops below 59.8 hertz for any amount of time. At this point, ERCOT may direct power companies to start rotating outages, which typically last about 45 minutes, to reduce strain on the grid.
