Texas Freeze Brings Grid Emergency

February 15, 2021

Image result for texas freeze

Apparently historic temperature anomaly brings enormous cold blob over North America. No one (yet) getting hit as hard as Texas.

I’ve been following energy twitter all morning, hard to get a bead on what’s happening, but finally Princeton Energy Ace Jesse Jenkins has shed a little light.

Jesse Jenkins on Twitter:

Confidential info from a market participant in ERCOT: As of ~10 AM Eastern time, the system has ~30 GW of capacity offline, ~26 GW of thermal — mostly natural gas which cant get fuel deliveries which are being priorities for heating loads — and ~4 GW of wind due to icing.

That is a HUGE amount of gas capacity offline, about 30% of total ERCOT capacity and ~half of the natural gas fleet, according to Dec 2020 Capacity Demand and Reserves report here: ercot.com/content/wcm/li…

Devastating for reliability. If we look at Winter planning scenerio ERCOT was using for 2026/27 (table below), they were planning for a peak demand of 67,512 “based on normal weather.” Demand last night (in 2021 not 2026/27!) was 69,150

Developing – more below:

Insurance Claims Journal- February 12:

The unprecedented Arctic blast that has gripped the U.S. for much of the week has paralyzed natural gas pipelines, brought deadly ice storms to Houston and is about to get worse.

Nearly 300 new daily temperature records could be set, mainly across the Great Plains from Canada to Texas through Tuesday, said Marc Chenard, a senior branch forecaster at the U.S. Weather Prediction Center. New York City will be dealing with ice and some snow showers from Saturday through Tuesday, with highs mostly hovering just above or below freezing.

As much as 6 inches (15 centimeters) of snow could fall in Forth Worth, Texas, over the weekend, with temperatures possibly plunging into the single digits Fahrenheit on Monday. A 130-vehicle pileup on Thursday on an icy highway in the city left six dead and dozens injured.

The cold is also weighing on the state’s sprawling energy infrastructure. Natural gas pipes and processing plants are starting to shut, disrupting output of the heating fuel.

“It is going to be a mess,” said Jason Dunn, a National Weather Service meteorologist in Fort Worth. “This is extremely unusual. I would go as far to say that it could be a historic event.”

Prices for gas, propane and heating oil, fuels used to heat homes, are also surging, and not just because of elevated demand. Temperatures are low enough to trigger so-called freeze-offs, when wells shut down because of liquids freezing inside pipelines. Texas facilities operated by pipeline companies DCP Midstream LP and Targa Resources Corp. were reported shut on Thursday due to the cold. Enbridge Inc. said it was limiting requests to transport gas on a pipeline stretching from Texas to New Jersey.

The impact on regional gas prices has been dramatic. The rate for next-day delivery at the Oneok hub, which hauls Oklahoma gas to networks serving the Midwest, closed at the highest since at least 1999 on Thursday. Gas futures climbed as much as 3.4% Friday.

Chenard said the country can expect a mix of ultra-cold lows, with high temperatures that struggle to be anything but frigid. What makes the outlook all the more remarkable is that it’s the dead of winter, so the air has to really chill to set new marks.

In Wind-heavy Iowa, with similar conditions – current outages as of mid-day 2/15/21, include 20 (that’s 2-0) customers.


Energy Analyst John Kemp on Twitter:

POWER GRID FAILURES never have a single cause. Grids should be managed conservatively with multiple layers of protection and reserves. Even if there is a single proximate cause, such as a single generator outage, the grid will only fail if those multiple layers have eroded

IN TEXAS, the proximate cause of grid failure was likely the extreme cold temperatures across much of the state. But big freezes are not that infrequent in the state. ERCOT’s system operating plan should have been able to cope with the cold. The question is why it failed.

IN TEXAS, the power crisis seems to have blown through multiple layers of system protection, including spinning reserves, peaking power reserves, and demand-response, all of which seem to have proved insufficient, leaving ERCOT no option but massive forced load-shedding.

ERCOT seems to have lost control of the power grid despite forecasts of extreme heating demand for days ahead, which implies something went seriously wrong with either system planning or system operation

ERCOT should have taken timely action to maintain power supplies and grid stability (including frequency control) well ahead of time, including scheduling extra firm generation or agreeing large load reductions. Instead, ERCOT seems to have been overwhelmed by a foreseeable event

Forcible load-shedding covering more than 18% of system-load suggests a catastrophic failure of the planning and/or operations process as events overtook the ability of the system to cope

Power grids should maintain enough of a reserve margin to ensure stable operation at all times including a reasonable worst-case scenario (e.g. the loss of a large generator or transmission line). ERCOT should have had enough generation on stand-by to cope with the cold weather

Either ERCOT was surprised by an unexpected event that was outside its planning system, or there simply wasn’t enough generation capacity to cope under a reasonably foreseeable event. Both scenarios suggest the system was not being managed within conservative limits

More Jesse Jenkins PhD:

If we look closer at the ERCOT Capacity, Demand and Reserves report, it also shows how much wind capacity they count on in winter peaking events (below). They plan on different % of installed capacity to be avialable in each region: 43% for coast, 32% panhandle & 19% for other 


In total, that means ERCOT is counting on 1,542 MW of coastal wind output, 1,411 MW of panhandle wind and 3,251 MW of other wind for a total of 6,204 MW of wind from currently operational facilities. 6.2 GW. Use that to track how wind performs during this emergency. Now if we look at another table, we can see how ERCOT thinks it will get its winter capacity by fuel type. They assume 100% of thermal units are available during winter peaking events. In reality, they lost 26 GW (if my source is correct) = 35% of total 75 GW of total thermal. (click figure to enlarge)

You can also see in that table they count on wind for <10% of total winter capacity + thermal for 89%. No matter how wind performs this week — important for future planning! — it is the big failure of thermal plants, mostly gas units, that is causing such widespread outages now As a New Englander until 2019, I know the region has long contended with — & planned to address — constraints on natural gas delivery in winter peaking events. They maintain large duel fuel capacity (gas units that switch to oil if needed) w/onsite storage. TX has clearly not. Texas relies overwhelmingly on natural gas units for winter peaking capacity, 66% of the total or 56.1 GW. If ~26 GW is offline due to inability to procure fuel (as I’ve been told), that is a devastating indictment of ERCOT winter planning & major cause of rotating outages.


We’ll learn a lot more as this winter emergency progresses, and as we get public reporting. That will inform how much of this was due to market design v planning failures. But counting on gas units to all be there there during extreme winter events is a clear recipe for failure. 

The primary issues now appear to be lack of fuel delivery to natural gas units, both due to frozen gas lines and to supply prioritization for gas heating demand over electric generators. Some wind generators out due to icing too, but that’s second order by far. I’ll end this here as I have to get back to work. I wish everyone in Texas best as they weather this emergency! 

For those interested in the source of the data above (also linked above), see ercot.com/news/releases/…. & spreadsheet here ercot.com/content/wcm/li…

ERCOT report shows increasing reserves in coming yearsNews releases published by ERCOT.http://www.ercot.com/news/releases/show/219347#:~:text=Resources%20totaling%201%2C917%20MW%20of,for%20inclusion%20in%20the%20CDRClarification: Info from a confidential market participant/source. Not that the info is confidential! Sorry. p.s. there’s a #climatechange angle in here, as usual. The polar vortex is breaking down due to Arctic warming, which is allowing cold weather to spread down into North America more often, including today’s cold snap 

Q&A: How is Arctic warming linked to the ‘polar vortex’ and other extreme weather?The past week has seen some brutal weather hitting the US and Canada. With cold Arctic air plunging south down to the US midwest, six states have seen temperatures lower than the south pole and at lea…https://www.carbonbrief.org/qa-how-is-arctic-warming-linked-to-polar-vortext-other-extreme-weather


4 Responses to “Texas Freeze Brings Grid Emergency”

  1. toddinnorway Says:

    Rooftop PV across Texas, homes, schools, malls, office buildings, all rooftops, with 2-4 hours of battery storage would have been producing fantastically in the cold sunny air with lots of reflective snow on the ground. Rooftop PV and battery storage would have saved the day in Texas now.

    When you see what the scarcity price is – $9000/MWh, you quickly conclude that this would have been the best solution economically speaking also, since rooftop PV and battery storage also help during the peak electricity demand times in August.

    All this unreliable natural gas peaker plant junk, what a horrible joke.

    Wind turbines have shut down in Texas because they are not winterized like turbines up north. So rooftop PV, local battery storage and winterized wind turbines is the answer, not more natural gas or coal!

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