Concerns about Texas' power grid continue after ERCOT underestimates Friday's peak energy demand

HOUSTON, Texas (KTRK) -- Since freezing temperatures from the arctic blast began Thursday, ERCOT has been holding up despite peak energy demands exceeding expectations Friday. But the test continues into the weekend and there are still concerns about how the state's grid will hold up.

During the past two days, CenterPoint Energy and Entergy reported thousands of outages impacting people throughout Southeast Texas. Crews have been working around the clock to restore power and get as many people out of the dark as possible.

RELATED: Power companies ask Texans to conserve amid freezing weather as ERCOT grid holds steady

According to the Texas Tribune, electricity demand hovered around 74,000 megawatts Friday morning. That surpassed the previous winter record of 69,871 megawatts during the February 2021 storm. However, that previous record demand didn't account for how much power Texans might have used if blackouts hadn't hit much of the state.

Dan Cohan, who is an associate professor of environmental engineering at Rice University explained why it's difficult for ERCOT to accurately estimate peak demand.

"We're in uncharted territory on this. We don't know how high the demand would have been in February 2021, if not for the blackouts that put a third of Texans into the dark, and so this is the first deep freeze that we've had without blackouts," Cohan said. "Since the economy and the population has grown so much, we have more homes heated with electricity than ever before. Predicting how that will perform in a deep freeze is something new for ERCOT to figure out."

Overnight, ERCOT announced it got emergency approval from the U.S. Secretary of Energy to bypass some environmental regulations in order to generate enough power.

Its notice stated, "The order authorizes certain electric-generating units within the ERCOT interconnection to operate up to their maximum generation output in certain limited circumstances, not withstanding federal air quality or other permit limitations."

READ ALSO: Can Texas' power grid handle this week's arctic blast? Energy experts weigh in

Given what our state went through during the February 2021 freeze, it's making a lot of people nervous about a potential repeat of blackouts. Companies like CenterPoint and Reliant Energy have asked customers to conserve energy to prevent service interruptions.

Dr. Joshua Rhodes, who is a research scientist at the University of Texas at Austin, explained the reasoning behind this.

"One of the things that with natural gas, you have to keep a certain pressure in the lines. If you don't keep, they depressurize and that can lead to things like gas leaks and some appliances not being able to operate," Rhodes said. "That's so whenever they are serving things like natural gas heaters or water heaters, they're able to provide at the pressure needed for these appliances to operate safely. It comes down to more of a safety issue than anything else right now."

Reliant Energy advises customers who have the means to conserve energy to do the following:

• If you have an electric heater, set your thermostat 1 to 2 degrees lower and run ceiling fans clockwise
• Roll up towels or blankets and put them under drafty doors and window sills in your home
• Hold off on running your dishwasher, washer, and dryer

CenterPoint Energy also issued these energy-saving tips:

• Change or clean your furnace filter to ensure good air flow
• Keep curtains and blinds open during the day to allow the sun's natural heat to warm your house. Close them at night, so you don't lose heat
• Be mindful of your pool heater usage. You can keep your pumps on without the heater to prevent your pool water from freezing

To check on the latest information about ERCOT's supply and demand, click here for their dashboard.

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