ERCOT and SPP, the two grid operators that bore the brunt of last February’s winter storm, both issued advisories Monday in advance of a cold front that is expected to sweep across the region and bring with it extremely low temperatures and wintry precipitation.

The Texas grid operator published a notice of “extreme cold weather event with potential icing conditions” Wednesday evening through Sunday. SPP meanwhile issued a cold weather advisory for its entire Eastern Interconnection footprint, effective Wednesday through Saturday.

ERCOT’s meteorologist said temperatures will likely be the winter’s lowest, reaching the teens in North Texas and low- to-mid 20s in Central Texas on Friday and Saturday morning. Icy precipitation is expected in West Texas, where most of the state’s wind farms are located.

As of Monday afternoon, ERCOT was expecting demand to peak at 72.5 GW on Friday morning, perilously close to the levels that brought the system to its knees nearly a year ago.

The demand projections have bounced around with the weather models. Last Friday’s prediction of nearly 73 GW for this Friday had been reduced to 68.7 GW on Monday morning, when models were predicting North Texas temperatures in the teens, rather than single digits.

“Load forecasts are driven by the weather,” Dan Woodfin, ERCOT’s system operations vice president, told stakeholders Monday. “We’ll continue to plan for a little higher [demand] than that.”

SPP’s weather advisory is a first step from normal operations. | SPP

Woodfin, briefing the Technical Advisory Committee, said staff will continue to maintain conservative operations, setting aside enough operating reserves to cover demand. He said ERCOT is expecting some level of gas restrictions and that staff have asked through a hotline that all generators place those outages as they occur in the outage scheduler.

Strong winds accompanying the front will increase wind production to about 25 GW, Woodfin said. Vendors responsible for wind forecasts believe that icy conditions will reduce that to 17 GW on Friday.

“At this point, we still look OK for Friday morning,” Woodfin said. “We haven’t made the decision yet, but we could be asking for more ancillary services.”

Concerns over the lack of public outreach were raised again last week when The Dallas Morning News reported that the grid operator had notified “many stakeholders” Friday morning “indicating that they have begun contacting state agencies and other authorities and are implementing an ‘aggressive grid management plan.’”

However, ERCOT has yet to issue a press release or use social media. The Texas Public Utility Commission on Sunday tweeted that it was “working closely” with the Texas Division of Emergency Management and other “critical state agencies to keep Texans safe.”

ERCOT did not respond to a request for comment on winter advisories, but it has issued the following statement:

“Because of the landmark reforms by the Texas Legislature and implemented by the Public Utility Commission, the grid is more resilient and reliable than it has ever been. ERCOT is confident it will be able to meet electric demand as a result of the rigorous new preparation and resiliency requirements.”

Stoic Energy President Doug Lewin, referencing temperatures that are not expected to be as low or as enduring as last February’s, said there should be no outages this week.

“If there are, the system’s far worse off than anyone thought,” he said.

SPP’s Advisory its Lowest Level

SPP’s is expecting potential icing effects, followed by lower-than-normal temperatures in its region.

The National Weather Service has issued a winter storm watch for central Oklahoma for late Tuesday through Thursday. It expects ice and snow will accompany a “significant drop” in temperatures, with highs falling to below freezing Wednesday and Thursday.

An SPP weather advisory is only a step beyond normal operations. They are only issued when staff expect extreme weather in the reliability coordinator service territory, and they do not require conservation measures.

The NWS said the main difference between this winter storm and last February’s is that the snowfall is expected to fall continuously and then move out, unlike last year’s intermittent precipitation.

The RTO will declare a resource advisory and then conservative operations before entering energy emergency alert levels.