NERC Case Notes: Reliability Standard PRC-010-0


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American Electric Power Service Corp, FERC Docket No. NP13-37-000 (May 30, 2013)

Reliability Standard: PRC-010-0

Requirement: 1.1.1

Violation Risk Factor: Medium

Violation Severity Level: Moderate

Region: TRE

Issue: On August 12, 2008, a phase-to-phase fault at the Laredo Plant Substation caused approximately 238 MW of Laredo area load to be removed by UVLS relays (out of the total Laredo area load of approximately 415 MW). During an event review and spot check of American Electric Power Service Corp (AEP), as agent for AEP Texas North Co, AEP Texas Central Co, and Public Service Company of Oklahoma, TRE found that AEP had not conducted an adequate internal review of relay reclosing function and coordination of load restoration with the RC and BA.

Finding: TRE found that the PRC-010-0 violation constituted a moderate risk to BPS reliability since having UVLS and UFLS relays without verified reclosing control function could have resulted in inappropriate reclosing, which would have reduced the effectiveness of the intended operations. But, in the August 12, 2008 incident, the UVLS program successfully performed pursuant to the engineering design and voltage was recovered in 15 seconds. In addition, the actual load that was interrupted was well over the 167 MW found by a prior UVLS study of the Laredo area to be necessary. The duration of the PRC-010-0 violation was from June 28, 2007 through January 3, 2012. AEP neither admits nor denies the violations. In approving the settlement agreement, NERC BOTCC considered the fact that AEP had a compliance program in place when the violations occurred (which was evaluated as a mitigating factor). And while AEP had prior violations of the Reliability Standards, it was not viewed as an aggravating factor since the prior violations did not indicate that there were any broader corporate issues involved. AEP was also cooperative during the enforcement process and did not conceal the violations. The violations did not constitute a serious or substantial risk to BPS reliability.

Total Penalty: $200,000 (aggregate for 6 violations)

FERC Order: Issued June 28, 2013 (no further review)

Tillamook People’s Utility District, FERC Docket No. NP10-2-000 (October 14, 2009)

Reliability Standard: PRC-010-0

Requirement: R1, R2

Violation Risk Factor: Medium (R1); Lower (R2)

Violation Severity Level: Not provided

Region: WECC

Issue: In June 2007, Tillamook People’s Utility District (Tillamook) self-reported that it had not conducted and documented an assessment of the effectiveness of its Under Voltage Load Shedding (UVLS) program and, therefore, it could not provide, upon the request of its Regional Entity, up-to-date assessments of the effectiveness of its UVLS program.

Finding: WECC found that the violations did not pose a serious or substantial risk to the bulk power system due to the nature and location of Tillamook’s facilities. In addition, Tillamook’s Balancing Authority gives voltage support to Tillamook. The violations were self-reported and were Tillamook’s first violations of this Reliability Standard. A mitigation plan has been completed.

Penalty: $0

FERC Order: Issued November 13, 2009 (no further review)