ERCOT provides final report on September 6 EEA event

ERCOT's Vice President of System Operations, Dan Woodfin, presented the Final Report on the September 6, 2023 emergency event to the Commission. He informed the Commission that ERCOT had issued a Request for Information to entities contributing to ERCOT’s Physical Responsive Capability (PRC) due to concerns about inaccuracies. At the point of lowest frequency, the calculated PRC exceeded actual capacity by 564 MW, stemming from thermal generators and wind resources misreporting capabilities. Energy storage resources also falsely reported capabilities, raising concerns for potential system or rule changes.

Commissioner Glotfelty expressed concerns about the increasing frequency of such reports until long-term reliability issues are resolved. He urged pursuing market solutions before operator actions and raised concerns about deploying Emergency Response Service (ERS) before entering an Energy Emergency Alert (EEA).

Woodfin informed the Commission there were 5,900 MW of thermal generation outages during the EEA and noted that the highest instantaneous net load in ERCOT history occurred on the day of the event. Commissioner Cobos inquired about the magnitude of future net loads with increased solar generation, to which Woodfin explained challenges in the evening associated with the decline of solar generation.

Commissioner McAdams emphasized understanding where energy storage is being depleted and the impact on deliverability. Commissioner Cobos recommended proactive measures for dealing with low wind and solar situations in the North when there is restricted generation in the South. Woodfin discussed ERCOT's collaboration with transmission owners to achieve incremental improvements and long-term planning.

Woodfin discussed potential improvements, including switching solutions and line enhancements, acknowledging ERCOT's lack of authority over transmission companies' rating methodologies. The Commission expressed concerns about the accuracy of line ratings and discussed ERCOT's role in ensuring accuracy.