Texas targets cascading outages risk

Texas regulators are moving to change how very large power users behave when the grid is disturbed. The immediate target is a class of loads ERCOT calls “large electronic loads” — mainly data centers and crypto-mining sites — that can drop off the system during short voltage or frequency events. ERCOT says that behavior can worsen an initial disturbance by abruptly changing demand and destabilizing the grid further. The proposed fix is not more generation capacity. It is a technical requirement that certain large loads ride through routine disturbances instead of tripping offline. ### What exactly is Texas trying to stop? ERCOT’s concern is a cascading event. In its December 2025 board materials, the grid operator said simultaneous tripping by multiple large electronic loads during a common disturbance could produce frequency and voltage instability. In the E&E News report published June 2, Texas A&M engineering professor Prasad Enjeti said a large data center dropping offline during a temporary disruption can upset the grid’s demand-supply balance and trigger more sites to disconnect. (eenews.net) ERCOT said it has identified 26 ride-through events involving large electronic loads since the beginning of 2023. In a February 2026 presentation, staff said they had observed multiple cases over three years in which one or more large electronic loads tripped or instantly reduced consumption during a system fault even though system protection had operated as designed. (ercot.com) ### Which facilities are covered? NPRR 1308 defines a “large load” as one or more facilities at a single site with aggregate peak demand of at least 75 megawatts behind common interconnection points. It defines a “large electronic load” as a large load where 50% or more of the site’s demand is power-electronics-based computational load, including data centers and cryptocurrency mining facilities. ERCOT said it chose that definition to focus specifically on those facilities, even though other industrial loads also use power electronics. (ercot.com) The proposal is not fully retroactive. ERCOT’s board materials say sites that had approval to energize, or had completed interconnection studies and agreements before November 14, 2025, are exempt from the new requirements. ERCOT also said exempt sites could still face curtailment under certain system conditions if they do not meet the proposed standards. (ercot.com) ### What does “ride through” mean in practice? NOGRR 282 would set minimum frequency and voltage performance requirements. ERCOT’s February presentation says covered loads must continue consuming electric current from the grid during specified frequency deviations rather than instantly tripping or transferring to backup generation. The draft table requires continuous ride-through between 58.8 hertz and 61.2 hertz, with 299-second ride-through at narrower bands outside that range. (ercot.com) That matters because the grid problem here is dynamic. ERCOT is treating resilience as the ability of connected equipment to stay stable through short-lived disturbances, not simply whether the system has enough installed megawatts on paper. That is an inference from the rule text and ERCOT’s stated justification that the risk comes from how large electronic loads respond during faults and frequency events. (ercot.com) ### Why are developers pushing back? Data center developers and other stakeholders have argued that ERCOT is moving too far, too fast. E&E News reported that some developers said the grid operator was overstepping its authority and unfairly targeting AI projects and crypto-mining facilities. ERCOT’s issue pages show comments from the Data Center Coalition, Google, Texas Blockchain Council, Vistra and other market participants as the proposal moved through the stakeholder process. (ercot.com) The dispute is partly technical and partly commercial. Ride-through requirements affect how engineers specify uninterruptible power supplies, inverter controls, transfer schemes, protection settings and plant-level controls. They can also affect project schedules, interconnection studies and the conditions attached to energization. That engineering implication is an inference from the scope of the proposed rules and ERCOT’s focus on customer-owned equipment performance. (eenews.net) ### What happens next? ERCOT’s board was set to vote June 2 on sending the ride-through rules to the Public Utility Commission of Texas. Under Texas law, PUCT approval is required for ERCOT rules, and the commission’s calendar lists an open meeting for June 18. ERCOT’s calendar also lists a Large Load Working Group meeting on June 19, suggesting the technical work will continue as the state moves toward final approval later this year. (ercot.com) (eenews.net)