Twice in one week in this month, and for the first time in five years, the owners of power lines and distribution networks across Texas found themselves in an electric game of chance as near-record temperatures prompted an energy emergency.
As the temperatures rose, demand from air conditioners also rose, the state’s grid operator found itself with a decreasing margin of reserve power. And when the amount of spare capacity toppled below a tripwire of 2,300 megawatts on Aug. 13 and again Aug. 15, the Electric Reliability Council of Texas, or ERCOT, was forced to take actions. A wind farm in Adrian, Texas. Texas is the biggest producer of wind power in the country, but the wind died down during the height of this month’s heat wave. The U.S. electric grid has changed dramatically from even just a decade ago. Though the energy emergency showcased the advances that allowed grid operators to rapidly remove load from the grid while ramping up output, they also exposed how changes to the state’s electricity supply may have contributed to the problem. Booming oil and natural gas production in Texas have caused gas prices to plummet, forcing more-expensive coal out of the market. Even renewables such as wind and solar, which had seen their costs drop, have become cheaper than coal. By the end of 2018, four big coal plants — accounting for roughly a quarter of the state’s coal generation — were taken offline, prompting federal energy watchers to express concern about the “smaller cushion of resources to meet summer peak demand and an increased risk of grid stress conditions.”
Amid bargain-basement prices for gas, there hasn’t yet been an incentive for the state’s power market to build anything other than natural gas plants, wind and solar resources. But wind is intermittent, and the wind died down during the height of this month’s heat wave, ERCOT found itself with even fewer sources of electricity.