Getting Ready for Winter’s Weather Whiplash

That time of year again. Polar Vortex season.

Everybody’s heard about the Texas Valentine’s Day Blackout of 2021 – in which Winter Storm Uri wiped out a significant portion of generation across the Texas Grid, known as ERCOT (Energy Reliability Council of Texas).
Others may not know that there has been a pattern of similar events, common enough to make it clear that dependence on gas generation during cold extreme events is risky, and becoming riskier, as my interviews above, with Judah Cohen of MIT, and Martha Shulski, who at the time was Nebraska’s State Climatologist.
The concern is that in a climate change regime, these events may be getting more frequent and severe.

One less discussed example of the problem is the near train wreck outages that occurred on December 21-24, 2022, on the PJM, which is the nation’s largest Grid System operator, covering more or less the Mid-Atlantic and some Southeastern portions of the US.

Winter Storm Elliott Frequently Asked Questions – PJM:

1. What were the operating days like on Friday, Dec. 23, and Saturday, Dec. 24?
   
   At the start of the day on Dec. 23, PJM had approximately 12,000 MW of forced (or non-planned) outages among its generation fleet. To account for the uncertainty of the weather conditions, PJM set up the operating day by committing approximately 133 GW of energy in the Day-Ahead Market and an additional 9 GW of available 30- minute reserves. In addition, approximately 13 GW of short-lead units were reported as available based on the
   operating parameters submitted to PJM, for a total of 155,750 MW of available generation that Friday. 

This well exceeded the PJM load forecast peak of about 127,000 MW for the day.

The weather on Dec. 23 was unprecedented for that time of year, given the severe temperature drop and resulting spike in load. The record-breaking plunge of 29 degrees over 12 hours on Dec. 23 surpassed the previous PJM record of a 22-degree drop during the 2014 Polar Vortex.

As cold weather gripped the PJM region and power needs spiked, PJM began seeing high levels of forced generation outages. PJM implemented emergency procedures, including calls for synchronized reserves, an RTO-wide (RTO = Regional Transmission Operator, another name for the Transmission system operator, PJM) Maximum Generation Emergency Action and a call on demand response.

The purpose of the Maximum Generation Emergency Action is to increase the PJM RTO generation above the maximum economic level.

As temperatures fell, power demand rose to a peak of about 135,000 MW Friday evening. Around the same time, forced outages reached as high as 34,500 MW. Shortly before midnight Friday, PJM issued a Call for Conservation for the entire footprint, asking consumers to cut back on their energy use where possible between the hours of 4 a.m. on Dec. 24 through 10 a.m. on Dec. 25.

The demand continued after the peak on Dec. 23 and into Dec. 24. Even the valley, or low-point of demand, on Dec. 24 was significantly greater than any other peak, or high-point of demand, for that date in a decade.

Generation outages further expanded to an estimated level of nearly 46,000 MW by Saturday morning (this figure was updated to approximately 47,000 MW at the Feb. 9 Operating Committee). Factoring in a number of reserve generators that missed scheduled start times Saturday morning or operated at less than capacity, combined with PJM’s inability to replenish pumped storage based on the lack of availability of generators overnight, PJM was missing approximately 57,000 MW of its generation fleet by the morning peak of Dec. 24, the coldest day of the holiday weekend.

2. What happened at the evening peak on Saturday (Dec. 24) through Sunday morning peak (Dec. 25)?

Heading into the peak for Saturday evening, there was still uncertainty about resource performance. Some resources informed PJM that they would come offline at 6 p.m. because of emissions limits. With these factors in mind, PJM submitted a petition to the U.S. Department of Energy (DOE) Saturday afternoon.

At 5:30 p.m. the DOE issued an emergency order, under Section 202(c) of the Federal Power Act, determining that an electric reliability emergency existed within the PJM region that required intervention by the secretary of the DOE to keep the power flowing.

The Emergency Order posted was effective Dec. 24, 2022, through noon Eastern Standard Time on Dec. 26, 2022.

The order authorized all electric generating units serving the PJM footprint to operate up to their maximum generation output levels under limited, prescribed circumstances, even if doing so exceeded their air quality or other permit limitations.

Two generating units that fell under the DOE order ran at levels that exceeded their environmental permitting limits.

The Department of Energy requires PJM to identify those generators, which were Bethlehem Energy in Bethlehem, Lehigh County, Pennsylvania, and York Energy 1 in Peach Bottom Township, York County, Pennsylvania.

Altogether, calls for conservation, a Maximum Generation Action and demand response are believed to have eased operating conditions through the Dec. 24 morning peak of about 129,000 MW and the evening peak that day of about 126,000 MW.

PJM was able to come out of its Maximum Generation Emergency at 10 p.m. on Saturday night, meet the morning peak on Dec. 25 and end all emergency procedures at 10 p.m. Sunday.

The Independent December 23, 2022:

Deadly winter storm Elliot has ravaged the US from coast to coast, leaving nearly two-thirds of the country without power as millions of Americans brave plunging temperatures. 

Satellite images sourced by NASA and the National Oceanic and Atmospheric Administration (NOAA) show Elliot making its way from Canada before landing south to the Rio Grande, Gulf Coast and central Florida, and from the Pacific Northwest to the Eastern Seaboard.

The storm, which brought dangerous howling winds, and blinding, heavy snowfall, was described as “one of the greatest extents of winter weather warnings and advisories ever,” by the National Weather Service. With temperatures continuing to plunge as low as minus 40 degrees, the service warned that Elliot could become a bomb cyclone if it meets warmer air in its path.

Natural Gas Intel:

FERC, NERC and the regional entities plan to coordinate with other federal agencies, states and utilities to identify problems with the performance of the bulk power system. Where it is appropriate, the regulators plan to recommend solutions for addressing issues.

“There will be multiple lessons learned from last week’s polar vortex that will inform future winter preparations,” NERC CEO Jim Robb said. “In addition to the load shedding in Tennessee and the Carolinas, multiple energy emergencies were declared and new demand records were set across the continent.

“And this was in the early weeks of a projected ‘mild’ winter,” Robb said. “This storm underscores the increasing frequency of significant extreme weather events (the fifth major winter event in the last 11 years) and underscores the need for the electric sector to change its planning scenarios and preparations for extreme events.”

Cascading Risks: Understanding the 2021 Winter Blackout in Texas:

The primary culprit for the electricity system failure was problems in electricity production from natural gas. About 40% of natural gas production was not available during the crisis. Texas’ gas, electricity, and water systems are inter-linked so failures in one of them can lead to cascading effects on the others [25]. The natural gas system relies on electricity, and the electrical system relies on gas. Thus, constrained gas limits the ability to generate electricity and constrained electricity limits the ability to supply gas which in turn further limits the ability to generate power in a vicious circle. Power outages in turn can lead to failures in the water supply.