Texas came uncomfortably close to another round of rolling blackouts Tuesday night because grid operators misjudged the weather. The Electric Reliability Council of Texas, which manages most of the state’s grid, had counted on a mild cold front sweeping the state, lowering demand for power. It didn’t happen. As a result, demand on the grid was about 3,000 megawatts higher than anticipated — or the equivalent of 600,000 homes.
“It’s a disgrace for a power grid in modern times to struggle to keep the lights on during a mild day,” said Daniel Cohan, an associate professor of environmental engineering at Rice University. “We’ll be in trouble when a summer heat wave comes in and demand is one-and-a-half times as much as it was yesterday.”
Shoulder Season
Weather typically usually doesn’t have a big impact on electricity demand in spring and fall. Those are the so-called shoulder seasons when customers are neither cranking their heaters nor blasting their air conditioners. On Tuesday, temperatures in Dallas, Brownsville and Houston were moderately higher than normal, reaching or exceeding 80 degrees Fahrenheit (27 Celsius). That, combined with a dearth of generation, prompted Ercot to ask for conservation efforts for almost four hours.
“Yesterday was an odd day,” said Matt Rogers, president of the Commodity Weather Group LLC in Bethesda, Maryland. “There were thunderstorms in West Texas that kept wind generation lower than normal. They are going to have another West Texas wind dip today, but not as much as yesterday.”
Ercot on Wednesday warned that it was again anticipating tight grid conditions, but didn’t call for conservation. The grid operator forecasted low wind and solar output for the day, while a forced power-plant outage in the Rio Grande Valley added to the large number of plants already down for maintenance.
Texas has long taken a laissez-faire approach to its power grid, allowing market forces — rather than regulations — to ensure there’s enough power on hand to satisfy demand. State lawmakers have been reluctant to rethink that method as they consider addressing the problems that led to the crisis in February.
The market is designed to operate with thin reserve margins. Unless lawmakers intervene to change that, weather will continue to beget volatility and chaos, said Katie Bays, an analyst at FiscalNote Markets.
“Texas is a goat rodeo,” Bays said in an interview. “The state doesn’t want to intervene in the market, but the way that Ercot is operating is a feature — not a bug.”