NERC FFT Reports: Reliability Standard INT-004-2


2 min read


Central Arizona Water Conservation District (CAWC), FERC Docket No. RC13-3-000 (December 31, 2012)

Reliability Standard: INT-004-2

Requirement: 2

Region: WECC

Issue: CAWC, as a Purchase-Selling Entity, self-reported three possible violations of R2 of INT-004-2 to WECC on August 1, 2012, citing that CAWC traders did not update tags as required by INT-004-2 R2.1 and R 2.2. WECC found that from the three occasions, CAWC failed to update 12 tags in total as well as failed to carry out the procedures that necessitate tag updates. WECC also determined that these failures resulted in a deviation of the hourly average energy profile by more than 10% in the first instance, by more than 25 MW in the second instance, and a loss of 183 MW for serving load and excess sales in the third instance.

Finding: WECC found that the issue posed a minimal risk to the reliability of the bulk power system. For one, WECC determined that the source of the violations in each case was human error. WECC found that CAWC knew about the status of generation plant interties and load profiles in real-time via SCADA. Additionally, the tags that failed to be updated were only those that were used for the hourly load profile of the Navajo generation unit; CAWC had the capability to ramp up generation at other locations to make up for the generation shortage at Navajo and to make sure loading voltage remained stable.

Tennessee Valley Authority – TVAM (TVAM), Docket No. RC13-7-000 (March 27, 2013)

Reliability Standard: INT-004-2

Requirement: 2/2.2

Region: SERC

Issue: TVAM submitted a self-report in July 2012 alerting SERC to a compliance issue with INT-004-2. TVAM stated that, as a PSE, it had not updated the dynamic tag for the estimated generation at one of its wind farms for a four-hour period due to incorrect information on the display screens used for monitoring wind generation. TVAM found that a software configuration change to the Resource Market Operator Portal had left a source code error involving a time zone conversion, and therefore, the wind generation monitoring screens were showing false data. TVAM reviewed its records after discovering the issue and found 12 other instances equaling 36 hours over a three-month period where the tags had not been properly adjusted.

Finding: The issue was deemed to pose minimal risk to BPS reliability and not serious or substantial risk because it did not result in the issuance of any TLRs. The result of not updating the wind forecasts in the flowgate calculations would be no more than a 1% error to any TLR corrective action that could have possibly occurred.