The Federal Energy Regulatory Commission took steps to bolster the bulk power system's protections against geomagnetic disturbances, showing support for certain reliability standard revisions but also seeking further improvements to better address risks associated with the high-impact, low-probability threat.
Geomagnetic disturbances, or GMDs, can result from solar flares or solar mass ejections that, with varying intensities, distort Earth's magnetic field. Those events could spur widespread blackouts and damage equipment critical to the reliable operation of the grid, but they have been so rare that preparing for them is problematic.
During FERC's May 17 monthly open meeting, FERC Chairman Kevin McIntyre commended staff's work on a notice of proposed rulemaking (FERC docket RM18-8) that he said advances the efforts to protect the grid from GMD events.
FERC approved the reliability standard aimed at preparing the grid for GMDs in September 2016 in Order 830 (RM15-11). The standard requires transmission and generator owners, planning coordinators and transmission planners to assess the vulnerability of their systems to a benchmark, or one-in-100-year, GMD event. They also were directed to develop plans to mitigate any adverse impacts that could lead to instability, uncontrolled separation or cascading failures of the electric power grid. The vulnerability assessments must be conducted once every 60 months.
The modified standard, as proposed by NERC, also includes requirements for the collection of geomagnetically induced current monitoring and magnetometer data needed for model validation and situational awareness and adds deadlines for developing and completing corrective action plans associated with the benchmark GMD event.
FERC's NOPR
FERC, however, found that NERC's petition falls short of Order 830's directive "not only to identify vulnerabilities arising from localized GMD events but also to mitigate such vulnerabilities." In particular, the commission faulted NERC for granting entities "the discretion to take corrective action based solely on the results of the spatially-averaged data while taking under advisement ('an evaluation of possible actions') the results of the supplemental assessment."
The NOPR also invited comment on an aspect of the standard that would allow entities to extend unilaterally their corrective action plan deadlines if "situations beyond the control of the responsible entity ... prevent implementation of the [corrective action plan] within the timetable" laid out by NERC.
FERC Commissioner Cheryl LaFleur, who has made GMDs a personal priority while at the commission, called the NOPR "an important next step" in ongoing efforts to better understand and mitigate the risk of GMDs to the grid. Because "a lot of important research is still going on in this area," she said, "it is very critical that our protection against geomagnetic disturbance threats evolve as our understanding of the GMD impacts improves."
FERC Commissioner Neil Chatterjee said he appreciates the concerns raised by commission staff and the scientific community on the continually developing science around GMDs, and added, "I think the record in this proceeding reflects a reasonable approach to evaluating supplemental GMD events," he said. "Moreover, given the potentially catastrophic consequences of a severe GMD event, I think it's prudent to err on the side of action rather than inaction."
Chatterjee added that the question is not whether but when the grid will experience a severe GMD event. In light of the substantial complexity surrounding the matter, he invited comments from NERC and others "on whether there are ways to address the identified issues in a more effective or efficient manner."
Comments are due 60 days after the NOPR is published in the Federal Register.
Jasmin Melvin is a reporter for S&P Global Platts, which, like S&P Global Market Intelligence, is owned by S&P Global Inc.
