Once again, ERCOT is calling on Texans to conserve electricity use Wednesday evening.
While temperatures have dipped, the reason is an unexpected loss of generation from some power plants.
The many calls to conserve electricity this month are reminders of the frailty of the Texas grid.
An ERCOT Reliability and Markets Committee is working to figure out how the state’s grid can best incorporate batteries as another source of power.
“This summer, demand is exploding,” said PUC Commissioner Lori Cobos. “We need resources now.”
Energy economics expert Ed Hirs with the University of Houston says Texas is adding batteries to the grid rapidly, but the state still does not have enough battery power to get through the evening hours when solar generation declines.
“The way a battery makes money, is, it buys low when there’s low demand periods, and it sells high,” he said. “And so this gives them a tremendous opportunity to make a very large amount of money in in a short space of a day.”
Batteries can store energy from any source, ranging from solar to natural gas. But they make up a very small portion of the grid right now.
“When we’re using more than 80,000 megawatts and a peak, summer afternoon and evening, and the most the batteries are contributing as maybe 600 megawatts. It’s a small portion. It’s less than 1%. It’s significant,” Hirs said.
In Wednesday’s meeting, committee members discussed how the state should manage and incentivize power from batteries.
“This is a recognition that that batteries are a major future resource for ERCOT,” Hirs said.
But Hirs says they are just one piece of the puzzle.
“The ERCOT grid is growing by leaps and bounds with the population and economy growth in Texas,” he said. “We’re still going to be facing five years of ERCOT weather roulette if we don’t add additional dispatchable resources to the grid.”
It’s something the many conservation notices show us.
“It’s also a daily reminder that the legislature has not done its job,” Hirs said.
The ERCOT board will vote on the proposal about battery resources on Thursday or send it back for further review.
Some experts are concerned that ERCOT is poised to make it more difficult for battery sources to operate in Texas, potentially curtailing an important resource in times of need.