FERC Releases NOPR to Approve SERC Regional Reliability Standard on Automatic Underfrequency Load Shedding Requirements
On July 19, 2012, FERC issued a Notice of Proposed Rulemaking (“NOPR”) proposing to approve a new National Electric Reliability Corporation (“NERC”) regional reliability standard governing the coordination of automatic underfrequency load-shedding (“UFLS”) schemes within the SERC Reliability Corp. (“SERC”).
Under FERC Order No. 672, NERC may propose region-specific standards that are 1) just, reasonable, not unduly discriminatory or preferential, and in the public interest and 2) more stringent than the continent-wide standard or “necessitated by a physical difference in the Bulk-Power System.” In accordance with this rule, on February 1, 2012, NERC submitted a petition to FERC seeking approval of regional Reliability Standard PRC-006-SERC-01, which will only apply to applicable registered entities within the SERC Region.
According to NERC, the proposed regional reliability standard adds a level of specificity and additional coordination that is not contained in the existing, continent-wide UFLS reliability standard, PRC-006-1, but that is necessary for the development and implementation of UFLS schemes in the SERC Region. To that end, NERC explained that the regional standard “is designed to work in conjunction with the NERC standard to effectively mitigate the consequences of an underfrequency event, while accommodating differences in system transmission and distribution topology among SERC Planning Coordinators due to historical design criteria, makeup of load demands, and generation resources.” As one specific example, the existing reliability standard applies only to Planning Coordinators, Transmission Owners, Distribution Providers and UFLS entities, whereas the proposed regional standard also adds Generator Owners to the Applicability section.
In the NOPR, FERC proposes to adopt NERC’s implementation plan, violation severity levels and proposed effective date for PRC-006-SER-01. FERC also notes a possible inconsistency between the NERC continent-wide standard and the newly proposed regional standard with regard to the timeline for implementing changes to a UFLS system, and thus clarifies that FERC will not interpret the proposed regional standard in a manner that will counter the continent-wide standard. Finally, FERC proposes to modify NERC’s related violation risk factor setting from “medium” to “high” so that the continent-wide standard and the regional standard, which address similar reliability goals, are treated comparably.
FERC also proposed to adopt NERC’s request that the different aspects of the proposed regional standard become effective over a staggered period of thirty months following the effective date of FERC’s Final Rule in order to provide affected entities adequate time to respond to UFLS changes. Comments on the NOPR are due sixty days after its publication in the Federal Register.
For a copy of the NOPR, click here.