The ability of Texas—America’s oil and natural gas hub—to avoid blackouts during this summer’s punishing heatwaves is hinging largely on a different source of energy: wind power.
On breezy days, Texas has plenty of electricity to spare—even as demand surges to unprecedented levels. On Wednesday, for instance, power use is forecast to skyrocket to a record 80 gigawatts. But officials haven’t even asked for conservation, thanks to vast farms in the Texas Panhandle and along the Gulf Coast that can supply about half of the grid’s needs on the windiest days.
When the wind ebbs, however, it’s an entirely different story. Take last week. Demand for power topped out at about 78 gigawatts. Yet, the grid operator had to beg residents and businesses to reduce power use because wind was sluggish.
Those wide swings underscore the challenge of managing a grid heavily reliant on power sources subject to changing weather. Yes, coal and natural gas plants can unexpectedly break down—another reason why officials needed to ask for conservation last week—and a problem that has confronted the state this spring and summer. But time and again, wind has been a crucial factor in whether Texas has enough power this summer.
“Whether or not Texas is short on resources is largely dependent on the wind,” John Moura, director of reliability assessment and performance analysis at the North American Electric Reliability Corp., a regulatory body that oversees grid stability, said during a briefing Wednesday.
Power demand Wednesday afternoon is poised to set the 11th record on Texas’s main grid since late June. But there’s sufficient output, according to the Electric Reliability Council of Texas, which operates the grid. Wind is expected to supply about about 8.7 gigawatts of capacity in the mid-afternoon when usage peaks, above the 6.8 gigawatts available during the peak hour July 13, when the state came perilously close to running short.
Wind last year constituted 24% of energy use, according to Ercot. Natural gas made up 42% and coal 19%.
Texas relies almost exclusively on market forces to determine what power plants are built in the state. For at least a decade, turbines have been among the cheapest facilities to build—a big reason why Texas is the biggest wind state. Most days, that’s fine. But when gusts fade, temperatures soar and fossil-fuel plants are shut, the state’s power grid can find itself in a pinch.
Developers are installing big batteries on the Texas grid, which help make up the shortfalls for when wind slacks. Eventually, they could smooth the ebbs and flows from intermittent renewable power. But the grid doesn’t have enough of them yet.
–With assistance from Brian K Sullivan.