Texas grid vulnerable to blackouts in extreme scenarios, ERCOT says as it adds storage to assessment

Dive Brief:

Texas utility regulators and the state’s grid operator say they are confident the electricity system will remain reliable this winter, though a seasonal assessment issued Tuesday shows blackouts are possible under some extreme scenarios.
“The elements that are within our control, related to the reliable operation of the grid, are as strong as I've ever seen them going into this winter season,” Pablo Vegas, the president and CEO of the Electric Reliability Council of Texas, said in a call with reporters Tuesday.
ERCOT’s Seasonal Assessment of Resource Adequacy, or SARA, shows forecasted peak demand of 67,398 MW this winter with about 87,300 MW of resources available. But in extreme situations with higher demand, unexpected generator outages and low wind output, the grid could be short by 9,000 MW or more.

Dive Insight:

Texas regulators and ERCOT have been working to bolster power reliability since Winter Storm Uri devastated the grid in 2021 and led to 246 deaths. Despite a host of market improvements and generator weatherization requirements, the grid’s reserve capacity is lower this season than last, said Vegas.

“Year to year we are developing more generation resources. The majority of those resources being added to the ERCOT grid tend to be renewable resources, like solar and wind,” Vegas said. Those resources do not perform as well in the winter, he explained, while the state’s population is growing rapidly and thermal generation resources have remained flat.

“We see demand having grown. [There is] upwards of about 5,000 MW more than we saw in last year’s SARA report,” Vegas said. “Texas is adding a city the size of Corpus Christi every single year in population, and the associated economic growth that comes with that is driving increased usage on the grid.”

One big change in the SARA for this winter: For the first time, ERCOT has included battery storage as a resource in its assessment.

“We saw the performance of batteries over the course of this last year, so we included a modest amount ... just under a gigawatt of battery storage,” Vegas said.

The inclusion of batteries follows a host of other operational changes noted by Public Utilities Commission of Texas Chairman Peter Lake.

“I want to remind folks about all of the reforms that we have put in place, especially ahead of last winter when we rapidly put in new rules to require generators to weatherize," Lake said. “In addition, we've built out and mapped a critical supply chain and critical infrastructure network to make sure that the natural gas supply chain stays online at all times and ensures the gas continues to flow to our generators.”

Texas energy experts say ERCOT’s seasonal assessment undersells the risk.

“A storm similar to Uri would again wreak havoc on the state. It was always unrealistic to think this was going to be ‘fixed’ in a year or two, but the lack of progress on several fronts, especially the demand side, is frustrating to say the least,” Doug Lewin, an energy analyst and president of Stoic Energy, tweeted following the SARA release.