By Rich Heidorn Jr. and Amanda Durish Cook
Uncharacteristically frigid weather prompted MISO to initiate a maximum generation alert for the South region for Jan. 17-18. With low temperatures averaging 13 degrees Fahrenheit on Jan. 17, MISO South’s peak load hit 32.1 GW, just short of the region’s all-time high of 32.7 GW set in August 2015.
MISO South reported about 17 GW of generation outages and derates that day, including nearly 10 GW in forced generation outages. Entergy Louisiana reported that about 32,000 homes and businesses lost power.
The FERC-NERC announcement cited “reports of multiple forced generation outages, voltage deviations and near overloads during peak operations.”
The inquiry, which FERC and NERC said is not an enforcement investigation, will seek to identify the causes and contributing factors to the event along with recommendations for improving operations in the future.
“This inquiry is timely as it will allow us to identify and share any potential lessons learned as we approach the coming winter season,” NERC CEO Jim Robb said. “It is also especially relevant that as the Western Interconnection reliability coordinator function fragments among multiple providers that we understand and underscore the importance of seamless RC-to-RC interactions.”
The Midwest Reliability Organization, ReliabilityFirst, SERC Reliability and utilities in the region will work with FERC and NERC staff on the inquiry.
The RTO declared conservative operations and a cold weather alert for MISO South — which spans Arkansas, Louisiana, portions of Mississippi and part of eastern Texas — beginning Jan. 15, when most of Louisiana was under a winter weather advisory.
Independent Market Monitor David Patton told stakeholders in March that if the RTO had not made emergency power purchases for South, regional supply would have dipped below load for several hours.
The Louisiana Public Service Commission called for an investigation of the episode in January. (See Louisiana Regulators Question MISO South Max Gen Event.)
MISO spokesman Mark Brown said the RTO doesn’t mind re-examining the event.
“While MISO and its neighbors worked together to maintain system reliability during the event, we recognize the opportunity to collaborate on changes that improve coordination during extreme events. We welcome the opportunity to advance the understanding within the industry and how MISO and its neighbors can continue to work together to support reliable and efficient operations,” Brown said in an emailed statement to RTO Insider.