Because of low wind and potential low solar generation, the Electric Reliability Council of Texas (ERCOT) on Sunday asked Texas residents and businesses to conserve electricity use. ERCOT's request was the fourth consecutive day that the manager for most of Texas' electric grid had asked Texans to conserve because of low output from renewable energy sources.
"Current forecasts are showing a potential to enter emergency operations this evening because of expected low wind and potential low solar generation and high demand," announced ERCOT in an Aug. 27 press release. "ERCOT will continue to closely monitor conditions throughout the day and will keep the public informed through our communications channels."
ERCOT issued a Conservation Appeal to Texas residents and businesses for Sunday, Aug. 27 from 4 – 9 p.m because of low wind and potential low solar generation in the face of high demand. Sunday was the fourth consecutive day that ERCOT had asked Texas residents and businesses to conserve electricity use. Starting on Thursday last week, ERCOT issued the calls for conservation because of concerns over the failure of renewable energy sources to meet expected levels of generation. On all four days ERCOT's conservation calls mentioned "low wind-power generation" as a reason for asking Texans to "conserve electricity use." Saturday and Sunday "potential low solar generation" was also listed as a factor.
ERCOT also said that high demand for electricity was also a factor in reaching out to Texas residents and businesses. Yet as Bill Peacock, the policy director at the Energy Alliance, explained, "High demand is a feature of every Texas summer. There is nothing new about that. The problem is when generation sources fail to meet expectations," in an Aug. 28 post on X, formerly Twitter.
Texas state Rep. Jared Patterson also expressed concern about the reliability of renewable energy. On Saturday, Patterson noted, "Thermal generation sources (natural gas, coal and nuclear) are performing at 72.5% of their installed capacity while renewable sources are performing at 26% of their installed capacity."
In his social media post, Patterson made it clear that he is not biased against renewables because of politics. "Please understand I’m not opposed to certain sources of generation because of politics or industry pressures," he said. "I’m opposed to any utility-scale generation source that doesn’t work when we need it." To support his comments, Patterson pointed out that "As a percentage of what’s available, more renewable sources are OFFLINE than thermal sources are ONLINE."
According to ERCOT, on Monday, wind generation showed little improvement in its ability to meet the high demands of Texas' summer heat. As demand for electricity on the grid began to rise at 8 a.m., electricity produce from wind farms began to fall.
Texas economist Vance Ginn issued a tongue in cheek response to ERCOT's fourth consecutive day of conservation calls. "Thanks wind and solar…," he wrote in an Aug. 27 social post on X.
The reliability problems with renewables stem from the fact that generation from wind and solar are dependent on the weather. Decreased wind speeds or increased cloud cover lead to lower levels of generation. The variability in generation from renewable sources is known as intermittency. In a 2022 report from the Austin Journal, Peacock explained the connection of intermittency with the need for conservation, "This heavy reliance on intermittent generation is why the Texas grid is facing reliability problems today."
The intermittency problems of renewables are just daily. They are also seasonal. For instance, from January through April this year when demand for electricity is typically lower, the total share of electricity in ERCOT from renewables averaged 40 percent, according to data from ERCOT. As temperatures and demand climbed in May, June, and July, generation from renewables averaged only 28 percent.