The Federal Energy Regulatory Commission (FERC) and the North American Electric Reliability Corporation (NERC) announced on Feb. 16 that they will open a joint inquiry into the operations of the bulk-power system during the extreme winter weather conditions currently being experienced by the Midwest and South Central states.
The severe cold weather over the weekend, and continuing into this week, has contributed to power outages affecting millions of electricity customers throughout the region.
“For now, the emphasis must remain on restoring power to customers and securing the reliability of the bulk-power system,” FERC and NERC said.
“In the days ahead, FERC and NERC will formally begin the inquiry, which will work with other federal agencies, states, regional entities and utilities to identify problems with the performance of the bulk-power system and, where appropriate, solutions for addressing those issues.”
Grid operators, utilities continue to grapple with freezing temperatures
Grid operators and electric utilities on Feb. 16 continued to grapple with bitter cold temperatures and address strains on the power grid that resulted in rotating outages starting on Feb. 15.
SPP early on the morning of Feb. 16 said it was declaring an Energy Emergency Alert (EEA) Level 3 effective immediately for its entire 14-state balancing authority area. SPP said that systemwide generating capacity had dropped below our current load of approximately 42 gigawatts (GW) due to extremely low temperatures and inadequate supplies of natural gas.
“We’ll be working with our member utilities to implement controlled interruptions of electric service throughout our region,” SPP said. “This is done as a last resort to preserve the reliability of the electric system as a whole. Individuals in the SPP service territory should take steps to conserve energy use and follow their local utilities’ instructions regarding conservation, local conditions and the potential for outages to their homes and businesses.”
SPP said that it was forecasting a morning peak of above 44.6 GW around 9:00 a.m. Central time.
Nebraska public power utility Lincoln Electric System (LES) on Feb. 16 said it had been instructed to shed load by SPP, the balancing authority for LES.
Rotating outages, also known as rolling blackouts, are controlled, temporary interruptions of electricity that reduce demand on the system. Outages are typically limited to 30 to 60 minutes, but may last longer, before being rotated to another location, LES noted.
Customers may experience multiple outages, LES said Feb. 16. Locations of controlled outages are determined by load shed requirements from SPP, which happens in minutes.
Nebraska Public Power District (NPPD) on Feb. 16 said in a Facebook post that in order to maintain system reliability, “we have just been informed by SPP that we need to do emergency coordinated interruptions of service. These 30-minute interruptions of service occur in real-time, so we have very little, if any, notice as to where these interruptions will take place. This is done to prevent longer, uncontrolled outages. If you experience a controlled outage, it should only last approximately 30 minutes.”
Another Nebraska public power utility, Omaha Public Power District (OPPD), on the morning of Feb. 16 reported that it had rotated another 12,222 customers back online as controlled outages continued Tuesday morning. Customers in Sarpy County and parts of west and central Omaha had been brought back online after undertaking approximately one-hour outages.
SPP “has directed all its member utilities, from North Dakota to Texas, to have controlled outages to help the power grid stay balanced. Record setting cold temperatures have settled in over the Central Plains region over the last few days and some snow and ice storms in the southern regions have also impacted the situation,” OPPD noted.
All utilities in the SPP footprint have been taking part in these controlled outages. For the OPPD area, those outages have been about one hour on a rotating basis. “While inconvenient for our customers and businesses impacted, the impacts of these outages have been minimal compared to winter snow and ice storms which can cause outages for days at a time.”
As of 10:05 a.m. CT, there were about 130 customers impacted by the rotating outages, OPPD said.
Missouri River Energy Services (MRES) noted that it was notified that SPP declared an EEA Level 3 starting on Feb. 16 at 6:15 a.m. “MRES had hoped to provide advance notice to its members but SPP was unable to notify us in time,” MRES said.
MRES is a joint-action agency made up of 61 member municipalities in the states of Iowa, Minnesota, North Dakota, and South Dakota. MRES provides its members with wholesale electricity along with a host of energy-related services.
MRES noted that the Western Area Power Administration (WAPA) and MRES are both transmission owners in SPP and both serve the power supply needs of MRES members, adding that MRES members located in the SPP footprint may be affected by this event.
Upon instructions by the reliability coordinator of SPP, WAPA began to curtail power to substations within the MRES membership, causing power outages in those communities. MRES was notified at about 10:50 a.m. that WAPA was in the process of restoring curtailed load. “MRES has no control over, and does not make any decisions regarding when and if these rolling blackouts are required,” it pointed out.
All MRES-operated generation resources have been operating to the fullest extent during this extreme weather event and are performing well, it said. Those include Laramie River Station in Wheatland, Wyoming, the Exira Station near Atlantic, Iowa, and the Watertown Power Plant in Watertown, South Dakota. Many MRES members with local generating units in their communities are also running those units to support power supply in the region.
MRES noted that it was asking its member municipal utilities to do whatever they can to reduce power usage in their communities, such as requesting that customers voluntarily reduce electric usage by delaying running the dishwasher and clothes washer, turning down the heat, and shutting off lights.
SPP subsequently declared a move from EEA Level 3 to EEA Level 2 at 11:30 a.m. Central time. “SPP’s forecasts anticipate that due to high load and persistent cold weather, it is likely its system will fluctuate between EEA levels over the next 48 hours,” it said in a tweet.
SPP as of 12:31 p.m. CT downgraded the EEA to level 1. This is declared when all available resources have been committed to meet obligations, and SPP is at risk of not meeting required operating reserves.
On Feb. 15, ERCOT reported that it had started to restore some of the power lost due to the winter weather event in Texas. As of 4 p.m. on Feb. 15, approximately 2,500 MW of load was in the process of being restored – enough power to serve 500,000 households. Earlier in the day, ERCOT entered emergency conditions and initiated rotating outages.
"The number of controlled outages we have to do remains high. We are optimistic that we will be able to reduce the number throughout the day." Dan Woodfin, Senior Director of System Operations, said on the morning of Feb. 16.
ERCOT said in a Facebook post that it should be able to restore some customers the afternoon of Feb. 16 due to additional wind and solar output and additional thermal generation “that has told us they expect to become available. But, the amount we restore will depend on how much generation is actually able to come online.”
Texas Gov. Greg Abbott on Feb. 16 declared reform of ERCOT an emergency item this legislative session. “In declaring this item an emergency, the governor is calling on the legislature to investigate ERCOT and ensure Texans never again experience power outages on the scale they have seen over the past several days,” a news release from the governor’s office said.
Texas public power utilities
Texas public power utility CPS Energy on Feb. 16 said that extreme cold temperatures and high energy usage “are continuing to force multiple power outages across our community and our state. If you are currently experiencing an outage, it is possible that the outage will continue for longer periods,” it said on its Facebook page. “If you have power, it is also possible you may experience a power outage and you should plan accordingly. Please seek shelter if you are in need of assistance.”
San Antonio, Texas, public power utility CPS Energy on Feb. 16 said that after exhausting all other options, these additional controlled service interruptions are a last resort, “and a step we take only when necessary to safeguard continued reliability of the statewide” ERCOT grid.
CPS Energy officials on Feb. 16 held a media briefing via Facebook Live to provide the latest update on outages caused by the extreme cold temperatures.
CPS Energy officials participating in the briefing included Paula Gold-Williams, President and CEO, and Rudy Garza, Interim Chief Customer Engagement Officer.
Meanwhile, Texas public power utility Austin Energy on Feb. 16 reported that as electric providers all wait for the ERCOT grid to stabilize, customers who have sustained outages should expect those outages to continue until the situation improves.
“All of our crews are ready to restore power to those affected as soon as we are authorized to do so by ERCOT,” Austin Energy said.
“We recognize the hardships and understand why customers are frustrated,” it noted.
Austin Energy General Manager Jackie Sargent was joined by city and county officials on Feb. 16 in a virtual press conference to address the unprecedented severe weather that has impacted residents. The replay of the press conference is available here.
The Midcontinent Independent System Operator (MISO) and its members managed multiple interdependent issues this week including transmission constraints and generation outages, MISO said on Feb. 16. MISO is also supporting its members’ restoration efforts in the South Region which remains under emergency declarations due to high demand and frigid temperatures.
MISO on Feb. 16 noted in a tweet that in light of uncertain operating conditions, it had declared additional emergency actions including instructing South Region members to issue a Public Appeal to conserve electricity (https://www.misoenergy.org/mcsnotification/?id=1121).
MISO has issued several emergency declarations since last week, some of which resulted in temporary power interruptions in parts of Southeast Texas, Southwest/South-Central Louisiana and South-Central Illinois. Most of those outages have been restored. Load demand is being driven by the freezing temperatures expected through the rest of this week, the grid operator said.
MISO said it continues to actively monitor developments related to the Arctic Outbreak, including information and guidance from our members and weather experts.