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ISOs, Regulators, Utilities Respond to Extreme Winter Weather Across U.S.

Feb. 16, 2021
'The lowest temperatures Texas has seen in decades necessitate a shared response across the state, from households to factories.'

ERCOT, the Kansas Corporation Commission, and Eversource were among the entities responding to the extreme winter weather and its impact on the energy industry on Feb. 15.

The National Weather Service reported on Feb. 15 that, as of 3:22 p.m. EST, millions of Americans are “under Winter Storm Warnings, Ice Storm Warnings, Winter Storm Watches, or Winter Weather Advisories as impactful winter weather continues from” coast to coast.

ISOs, RTOs declare emergencies

ERCOT on Feb. 15 said that it entered emergency conditions and initiated rotating outages at 1:25 a.m.

ERCOT noted that about 10,500 MW of customer load — or enough power to serve about two million homes — was shed at the highest point. Extreme weather conditions caused many generating units, across fuel types, to trip offline and become unavailable, ERCOT added, noting that there was more than 30,000 MW of generation forced off the system at the time of its statement.

The Midcontinent ISO (MISO), in its Feb. 15 statement, said that sustained frigid temperatures and winter weather impacting its South Region contributed to the loss of generation and transmission, leading to emergency actions in the region’s western portion to avoid a larger power outage on the bulk electric system.

Periodic power outages began early on Feb. 15 for some customers in Southeast Texas, MISO said.

MISO said that it and its members worked together to identify the worst-case scenarios to limit the effects of temporary power supply interruptions to those areas that will provide the most relief, with that plan focused on the forecast load demand and expert weather forecast, as well as the risks associated with generation availability and transmission capacity across the region.

In its Feb. 15 statement, the Southwest Power Pool (SPP) said that extreme cold weather created energy deficiencies in its region, with SPP declaring an Energy Emergency Alert (EEA) Level 2 beginning at 7:22 a.m. Central time. SPP noted that an EEA Level 2 requires it to direct its member companies to issue public conservation appeals.

SPP said that it declared a period of conservative operations for its entire balancing authority area at 12 a.m. Central time on Feb. 9; on Feb. 14, SPP declared an EEA Level 1, effective at 5:00 a.m. Central on Feb. 15. SPP said that an EEA1 signaled that it foresees, or is experiencing, conditions where all available resources are scheduled to meet firm load obligations and that SPP may be unable to sustain its required contingency reserves.

SPP noted that to bolster system reliability, it may require generating units to be available for upcoming operating days with notifications for commitment issued multiple days in advance.

Operating conditions may continue to tighten over the next several days because of the widespread and extreme cold winter weather event, as well as an inadequate supply of natural gas required to power some gas-powered electric generation units, SPP said, adding that it is coordinating with its members and market participants to respond to high electricity demand and ensure that the power grid remains reliable.

Regulator calls for ‘common sense conservation’

The Public Utility Commission of Texas on Feb. 14 noted that narrow margins between cold-driven demand and the supply of available power across the state are expected to occur periodically through Feb. 16.

"The lowest temperatures Texas has seen in decades necessitate a shared response across the state, from households to factories,” Commission Chairman DeAnn Walker said in the statement. “Along with the tools ERCOT uses to maintain the reliability of the grid, common sense conservation also plays a critical role in our state’s endurance of this challenge.”

The commission noted that ERCOT has called upon power consumers across the grid to reduce their electricity use as much as possible from Feb. 14 to Feb. 16.

“This record cold is not only compelling customers to increase their power usage to stay warm, it’s also icing wind turbines and straining our natural-gas powered resources,” Commissioner Arthur D’Andrea said in the statement. “With the grid pinched like that, ‘demand response’ in the form of reduced consumption is an essential shared action.”

The commission noted that household tips for reducing electricity use include: turning down thermostats to 68-degrees or lower; closing shades and blinds to reduce the amount of heat lost through windows; turning off and unplugging non-essential lights and appliances; and avoiding use of such large appliances as ovens and washing machines.

Kansas state regulators on Feb. 15 said that they issued an emergency order directing utilities to ensure that adequate amounts of natural gas and electricity are available to meet customers’ needs, including interconnected non-jurisdictional utilities that depend on them for power.

The Kansas Corporation Commission also noted that the prolonged stretch of extremely cold temperatures has increased demand, created natural gas supply constraints, and potentially reliability issues.

“It’s in every Kansan’s best interest to conserve electricity and natural gas over the next few days when possible,” Commission Chairperson Andrew French said in the statement. “Reducing your usage will help ensure everyone continues to receive these services, and it will save you money on future utility bills.”

Utilities are experiencing wholesale gas prices anywhere from 10 to 200 times higher than normal, the commission said, adding that those costs will eventually impact customers through increases in monthly natural gas and electric bills.

The commission noted that its order authorizes every jurisdictional electric and natural gas distribution utility that incurs extraordinary costs associated with ensuring its customers continue to receive utility service during this cold weather event to defer those costs to a regulatory asset account for future commission review, with that deferral being for accounting purposes only.

Southern utilities note outages

Oncor Electric Delivery Company on Feb. 15 noted that ERCOT has instructed utilities to begin rotating outages.

In a 9:15 a.m., emergency update posted after that statement, Oncor said that due to the severity of the electric generation shortfall, the company’s expected outage length of 15 to 45 minutes has been significantly extended, with outages due to this electric emergency potentially lasting for hours. Oncor said that it is also responding to separate outages caused by the record-breaking winter storm that continues to impact its entire service territory.

American Electric Power’s (AEP) AEP Texas, in a Feb. 15 statement, told customers that if they are experiencing an outage, then they will “likely be out of power for an extended period of time while this state of emergency continues.”

The company said that as of 10:30 a.m., the number of AEP Texas outages was about 362,000 across its service territory in south and west Texas.

AEP Texas said that while it continues to work with ERCOT to address the situation, it is too early to project when the situation will ease and the number of outages will begin to decrease.

The company said that if customers lose power, they should turn off their heating and large appliances to enable smoother service restoration, and that once power is restored, they should switch the devices back on gradually over the following 30 to 45 minutes.

CenterPoint Energy on Twitter said that on the morning of Feb. 15, conditions for power generation were, and continue to be, very serious, with ERCOT needing electric companies to reduce their load at a higher level and longer than originally thought, which is resulting in longer outages for customers.

“We appreciate our customers’ patience and understanding as we do what we can to manage through this significant state-wide power supply situation,” CenterPoint added.

AEP’s Public Service Company of Oklahoma (PSO) on Feb. 15 said that it is calling on customers to reduce energy use after receiving notice that morning from SPP.

PSO said that while it was requested to initiate planned outages for some customers on the morning of Feb. 15, that request has been put on hold and all customers have been restored.  With extreme cold conditions forecast for the next several days, the region’s energy supply may continue to tighten over the next several days, PSO said, adding that should another temporary interruption of power be required, customers should be prepared to be without power for about two hours.

Similarly, AEP’s Southwestern Electric Power Company (SWEPCO) on Feb. 15 said that it has ended the controlled outages implemented that day in an emergency procedure promoted by the extreme winter temperatures. The combined efforts of SWEPCO and other utilities achieved the required reduction in electricity demand and SPP returned to a lower emergency level focused on continued energy conservation, SWEPCO said, adding that it is completing power restoration to any remaining customers impacted by the temporary outages.

Utilities across the country experience harsh weather conditions

In the East Coast, Eversource on Feb. 15 said that with a winter storm expected to bring snow, ice, and freezing rain to New England late in the day and into Feb. 16, the company has line workers, tree crews, and support staff positioned across Connecticut to address any damage or power outages caused by the storm.

Dominion Energy Virginia on Feb. 14 said that its crews are working to restore power after more than 48 hours of freezing rain and ice accumulation brought damage to parts of central and southern Virginia on Feb. 13, including broken poles and hundreds of downed power lines. As of 3:30 p.m., on Feb. 14, crews had restored service to more than 175,000 of the more than 290,000 customers who had lost power, the company said.

On the West Coast, Pacific Power on Feb. 14 said that customers on Oregon’s north coast and parts of the Willamette Valley regained electric service as nearly 300 Pacific Power employees and contractors worked in freezing conditions to repair damage caused by heavy ice and snow.

As of 4 p.m. that day, 17,600 customers were in the process of being restored, down from 40,000 customers at the storm’s peak, the company said, adding that most customers were expected to have service restored by the evening of Feb. 15. The company noted that the communities with the largest remaining outages include Stayton/Mill City/Lyons with 7,634 customers; Dallas/Independence with 5,469 customers; and Albany/Millersburg/Corvallis with 3,848 customers.


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