The ERCOT TAC meeting held August 27, met to work through market-rule changes, reliability upgrades, and large-load integration. The agenda featured votes on multiple NPRRs/PGRRs/NOGRRs, a 2026 Ancillary Services methodology package, updates on Real-Time Co-optimization + Batteries (RTC+B), and status on major transmission projects and large-load interconnections. Here’s a summary of the key topics and takeaways.
2026 AS methodology
- What was on the table: ERCOT and the IMM walked through the proposed 2026 approach and posted a TAC ballot (i.e., up for TAC endorsement). Agenda listed both presentations and a possible vote.
- How the math works: ERCOT’s 2026 workstream builds on a probabilistic/Monte Carlo framework using inputs like net-load uncertainty and forced‐outage risk, and evaluating “risk producers” across hours to size reserves. (ERCOT workshops through spring/summer 2025 explored this.)
Protocol/Guide revisions (market rules)
- SCR832 (retire a TSP COPs report): System Change Request to discontinue an unused Current Operating Plans report to TSPs.
- NPRR1290 (RTC+B gaps/clarifications): Package of clarifications across Protocol Sections 2–22 to support Real-Time Co-optimization + Batteries (RTC+B). ERCOT filed multiple impact analyses and comment rounds in May–Aug 2025; TAC tracked it as a Board-bound item.
- NPRR1265 (Unregistered Distributed Generator): Implements HB 3390 reporting—creates UDG definition and reporting procedures for DG that isn’t formally registered.
- NPRR1266 (Transmission-voltage customer opt-out not transferable): Codifies that securitization opt-out status can’t be transferred if service changes hands; PRS advanced with a March 1, 2026 effective date in recommendations.
- NPRR1279 (Exceptional Fuel Cost): Lets generators include contractual and pipeline-mandated costs in EFC filings and strengthens IMM/ERCOT verification.
- NPRR1283 (SSR mitigation timeline): Moves subsynchronous-resonance study/mitigation from initial synchronization to initial energization, addressing commissioning-stage SSR risk.
- NPRR1291 (Demand Response report timing / PUCT 25.186): Aligns annual DR report timing/posting and data rules to new PUCT requirements; RMS/PRS actions and ballots ran June–Aug 2025.
For everything you need to know about ERCOT NPRRs and PGRRs, visit our Comprehensive Guide to ERCOT NPRRs & PGRRs Following August PLWG Discussions.
System operations & IBR capabilities
- NOGRR278 (aligned to NPRR1290): Operating-guide updates needed to implement RTC+B details (e.g., RRS with PFR MW limits and related control nuances).
- NOGRR272 (URGENT): Creates Advanced Grid Support requirements for inverter-based Energy Storage Resources (ESRs)—performance, controls, and support during low system strength conditions.
- PGRR121 (paired to NOGRR272): Adds model-quality tests and unit validation requirements for ESRs (effective for SGIAs executed on/after Apr 1, 2026 in draft language). TAC tracked it through ROS with iterative ERCOT comments in 2025.
Markets & credit: RTC+B Readiness
- RTC+B Task Force: Progress report toward the December 5, 2025, RTC go-live (market trials and interdependency tracking still on cadence).
- Standing reports: RMS/WMS presented routine market/process updates; CFSG took up credit-membership approvals per agenda.
Large-load & IBR Updates
- DAM price-correction review: ERCOT reviewed a day-ahead price correction related to an incorrect generic transmission constraint limit; similar correction topics have come to management/Board previously.
- LLWG: Status update on Large-Load Interconnections (process/reporting overseen by LLWG). Review our full overview of ERCOT’s most recent LLWG meeting here.
- RPG items at TAC:
- BTU – Texas A&M RELLIS Campus Reliability: Tier-1 project (~$271.5M; CCN required) to address thermal/voltage issues driven by RELLIS load; multiple RPG updates in 2025. Possible vote listed for TAC.
- CNP – Baytown Area Load Addition: Tier-1 project (~$141.65M, ISD Jan 2028); waive-notice + possible vote at TAC.
- GRIT update: ERCOT’s Grid Research, Innovation & Transformation program briefed TAC (innovation progress/milestones).
Governance & process
- Biennial TAC structure/procedures review: Conducted Aug 12; outputs inform committee/working-group alignment for the cycle ahead.
- Prioritization workshop: Project/initiative ranking workshop held Aug 25 to set 2H-2025 priorities for PRS/committees.
- PUCT ancillary-service cost-allocation study: New docket filings posted Aug 19, 2025 (PURA §39.1593) kicking off the study process at the PUC.
- September engagements: ERCOT Board meets Sept 22–23, 2025, with committee days that same week—TAC items feed into those agendas.
Turning TAC outcomes into action
Contact us to translate these TAC decisions into concrete next steps, prioritize your NPRR/PGRR compliance, tune IBR/ESR controls for NOGRR272, ready portfolios for RTC+B, and plan large-load and RPG pathways without schedule slips. We’ll map requirements to your assets and deliver a clear execution plan.
For more from this month’s ERCOT TAC meeting, view meeting materials here.
