The Electric Reliability Council of Texas is considering demand response, dynamic line ratings and other solutions to address transmission constraints in the southern portion of the state, grid officials told state regulators on Thursday.
ERCOT in February issued an operational notice identifying “a reliability need to limit power transfers in both south-to-north and north-to-south directions across interfaces that are generally south of San Antonio.” Details about what specifically could cause line overloads, potentially leading to cascading outages, is considered critical energy infrastructure information and is not disclosed by the grid operator.
Texas is experiencing rapid load growth, leading regulators and grid officials to consider new planning processes and resources. ERCOT anticipates about 152 GW of new load by 2030, driven by data centers, industrial electrification and other sources.
ERCOT officials appeared before the Public Utility Commission of Texas on Thursday to ask “whether the commission would like us to proceed forward to address some reliability risks that we see for this upcoming summer,” said Chad Seely, the grid operator’s senior vice president and general counsel. That could take the form of a request for proposals for demand response capacity that might be issued in May.
ERCOT is in the process of developing the framework for a possible RFP and is “drawing upon its experience and lessons learned” from an RFP it issued in October, for capacity contracts for the winter 2023-24 season, according to a Monday memo on the issue.
“This is a little bit different than what we did in October of last year,” Seely said. “And from those lessons learned, we are really seeking guidance from the commission. We've learned a lot going through that request for proposals, on how to kind of frame up and measure other types of resources besides just demand response.”
ERCOT sought 3 GW of capacity in the October solicitation, but canceled plans after finding no power plants willing provide the additional operating reserves. Instead, the grid operator received just a few offers from demand response providers.
PUCT Commissioner Lori Cobos said she is “fine with a demand response RFP.”
“This is not like the other RFP, where you just basically surveyed the market to see what kind of plants you can get,” Cobos said, talking through what the new request would look like. “This RFP is more strategic, based on shift factors and the value those megawatts will provide to the constraints.”
Commissioners appeared to generally approve of issuing an RFP, and Cobos said one could be issued in mid-May.
Grid-enhancing technologies offer potential solution
“Dynamically-rated lines is another opportunity we're talking to the local utilities about,” said Seely. There is "some new software that could provide value,” he said, and ERCOT wants to know “whether they're able to procure that and put that in place in time for the summer.”
Another possible solution to the transmission constraints includes changes to the “shadow price cap,” which is the maximum price ERCOT’s algorithm will assign to the cost of congestion on a given constrained transmission element.
“I think everyone is comfortable with the dynamic rating improvements, with the shadow pricing ... and on [demand response],” said Chairman Thomas Gleeson. But he said he wanted “just a little more discussion looking at the RFP ... to look for more capacity” than ERCOT found in its October request.
Dynamic line ratings were also discussed Tuesday at a meeting of ERCOT’s board of directors. Cobos asked about the potential for grid-enhancing technologies like DLR to expand infrastructure capacity.
“Dynamic line rating is something we’ve done here in Texas for years,” ERCOT President and CEO Pablo Vegas replied. “Many of the large transmission service providers and a good majority of the transmission lines in the state of Texas today are dynamically line rated, and we get the benefit of that throughout the year.”
