PUCT Issues Written Order on State Estimator Data

The PUCT has issued a final written order concerning amendments to Subst. R. 25.505, specifically concerning the release of the ERCOT State Estimator Report upon implementation of the nodal market (Project 38470). Though the Commission voted on the rule at its most recent open meeting, the final cuts made by the Commission were not definitively known absent the written order.

The Commission concluded that, "it is imperative that ERCOT timely disclose operational information related to the transmission system as soon as the nodal market is implemented."

In this vein, ERCOT was ordered to initially post the unredacted State Estimator Report information 60 days after the day for which the information was accumulated. This 60-day posting requirement is consistent with existing posting requirements under §25.505(f)(3)(B) for resource-specific information, and thereby avoids disclosing competitively sensitive information, the PUCT said.

Furthermore, ERCOT shall initially post a redacted State Estimator Report that avoids material disclosure of competitively sensitive information (e.g. data from which resource-specific output levels or offer curves could continually and systematically be derived), as soon as reasonably practicable after collection of the State Estimator data. In conjunction with the Independent Market Monitor and Commission Staff, ERCOT, through its stakeholder process, shall develop protocols that detail, at a minimum, the methodology, duration, and posting requirement of a redacted version of the State Estimator data.

The redacted report methodology developed through the stakeholder process shall be completed within 90 days of the start of the nodal market. If ERCOT is unable to develop a cost effective protocol for the redaction process of the State Estimator data within 90 days of the start of the nodal market, then the following information shall be released as soon as reasonably practicable:

(I) Current commercially significant constraints (CSCs) and closely related elements (CREs) line flows that are embodied in the competitive constraint list from the Competitive Constraint Test;

(II) For phase shifting transformers, tap positions and line flows;

(III) Voltages at all buses;

(IV) Line flows on lines that make up interfaces (import, export, flow gate, or stability); and

(V) Line flows on DC ties.

Finally, both initially and on an ongoing basis, ERCOT shall have the sole discretion to release relevant State Estimator data less than 60 days after the day for which the information is accumulated if it determines the release is necessary to provide complete and timely explanation and analysis of unexpected market operations and results or system events, including but not limited to pricing anomalies, recurring transmission congestion, and system disturbances.

"These requirements ensure that market participants will have timely access to transmission system information as soon as the nodal market is implemented," the Commission said.