Members of the Federal Energy Regulatory Commission on Jan. 18 praised the bulk power system's performance during a nationwide bout of extreme cold temperatures but cautioned that more work remains to bolster grid reliability.
A large blast of Arctic air began descending across the Lower 48 on Jan. 13, prompting regional grid operators such as the Midcontinent ISO, Southwest Power Pool and Electric Reliability Council of Texas Inc. to issue cold weather and resource advisories.
Unlike during severe winter storms in 2021 and 2022, however, the US power system has held up relatively well in the face of surging electricity demand in recent days, FERC Chairman Willie Phillips noted during the agency's Jan. 18 monthly open meeting.
"This extreme weather pattern covered most of the United States with temperatures in many areas that reached the single digits, the teens and had wind chill below zero," Phillips said. "We saw record or near-record demand for market operators across the country, and I would like to acknowledge and thank everyone that stepped up to help ensure grid reliability during the storm, from grid operators and planners to the generators and fuel suppliers."
The storm shows that generators must continue implementing recommendations from a report on a December 2022 winter storm that forced multiple utilities in the US Southeast to resort to rotating blackouts, Phillips said.
"It's only mid-January," Phillip said, "so we cannot rest."
Phillips added that the wide-area extreme weather event, the third of its kind in roughly three years, underscores the need for more electric transmission capacity. SPP, for example, imported a record 6.8 GW from neighboring regions during the event, surpassing import levels reached during a prolonged cold snap in February 2021.
Commissioner Allison Clements also highlighted the performance of renewable energy resources, battery storage assets, and demand response in Texas. Battery storage capacity in the ERCOT region has tripled since February 2021, while demand response has doubled to 4 GW.
ERCOT set winter peak demand records on consecutive days Jan. 14-16, topping off at more than 78,100 MW on Jan. 16. Clements noted wind provided 30% of the state's power supply and solar resources producing a record 14,000 MW.
ERCOT asked customers to voluntarily conserve power during the mornings of Jan. 15-16, but excess generating capacity kept wholesale power prices relatively low.
"This is a nice story to tell," Clements said. "Of course, it doesn't suggest we're in the clear or our work is done."
Commissioner Mark Christie warned that the US will continue to face winter reliability challenges as more fossil fuel-fired power plants retire.
The 13-state PJM Interconnection LLC system peaked at around 135,000 MW on Jan. 17, with gas-fired units generating 41% of the region's power mix, Christie noted. Nuclear plants supplied another 25%, while coal-fired units accounted for 24%.
PJM is anticipating roughly 40 GW of thermal generator retirements by 2030, raising concerns that retirements may soon outpace new capacity additions.
"Again, those numbers don't add up," Christie said. "You can't export something if you don't generate it."
"Looking at those generating mixes, those are dispatchable resources that were keeping the lights on and keeping the heat pumps going by and large," Christie continued. "If you don't maintain these dispatchable resources until you have an absolutely adequate replacement, we're not going to have the success we had in the last three or four days."
The North American Electric Reliability Corp. sounded similar concerns in its latest long-term reliability assessment.
Coming soon: Transmission planning rule
Following the meeting, Phillips told reporters that he expects the commission to finalize a highly anticipated rule on electric transmission planning and cost allocation "in the very near future."
Pressure has been mounting on FERC to strengthen and finalize the proposed rule, issued in April 2022, which would require transmission planners to account for the expected location of future generation resources. The proposed rule also set out a range of benefits for consideration in allocating the costs of new transmission lines, although many clean energy proponents are urging FERC to go further by requiring certain benefit-to-cost metrics.
In a Jan. 16 letter, 134 House and Senate Democrats told FERC that the final rule "must require consideration of a comprehensive and specific set of transmission benefits to consumers which should be used in cost allocation processes."
In addition to the planning rule, FERC has also opened a proceeding to explore setting a minimum requirement for interregional transmission transfer capability.
Phillips reiterated Jan. 18 that FERC's transmission-related rulemakings are among the commission's top priorities.
"We are working on them as fast as we can," Phillips said. "We will not delay, we have no plan to delay, and we will act on them as soon as they are ready to go out the door."
