Arctic Freeze in Texas 2021 - FAQ

[Update - due to the unanticipated interest in this post I have updated a few areas to hopefully clear up any confusion.]

Hello, as a 10 year resident of Texas, specifically the Katy area, 30miles west of Houston, I have personally lived through the recent Arctic Weather that totally disrupted the state of Texas.  I lost power to my home for about 50hrs, on two of the coldest nights, where the exterior temperature dropped to -16deg Celsius, or single digit Fahrenheit.

Getting back to normal at the end of the week, which included getting back on to social media and the various news media,  I was surprised at the amount of misinformation and plain incorrect information that was being passed around and reported on.

I have spent 20yrs in the energy business in various aspects of the supply chain in various countries. I am NOT an expert in the Texas Electrical Grid, but I know more than the average person.

I have taken this time to provide some answers to frequently asked questions I have received in the past week. This post is quite long and as you might expect the answers (from an engineer) can be quite long as well. To assist you, I have provided a short summary response first, followed by a longer response that holds some details and the limits of my understanding.

Hope this helps.

Frequently Asked Questions

Did the Wind Turbines fail early in the event and did this cause significant power black outs?

Short Answer: No.

Longer Answer: As the freezing rain passed through the larger Wind Turbine operations in West Texas, Wind Generated power was about 1.5GW lower than expected.  At the time this represented about 2.4% of the target power supply of 62.5GW, set by ERCOT. [Note these numbers are being updated as ERCOT completes its internal studies... so they are likely out of date when I wrote this].

ERCOT typically has 5% to 10% of managed capacity or spare capacity to manage if any of its power suppliers have issues. The drop of 1.5GW would fall within this spare capacity and would not have caused a power shortage.

BUT, the wind supply was affected for about 24hrs.  Wind generation was back up and running to full forecast by Tuesday.

[Update: To be clear ERCOT, the Electric Reliability Council of Texas, is the non-governmental body that manages the distribution of about 90% of the Texas Power Grid. ERCOT does not generate electricity, nor does it set the guidelines for generators. The guidelines for generation are managed by the Public Utility of Texas (PUCT).]

How cold was it?

Short Answer: Historically Cold! Houston broke a low temperature record that was 122 years old (6 deg F, Feb 12, 1899).  Dallas and northern Texas was below freezing continuously for more than 5 days.

Longer Answer: Texas typically measures freezing temperatures by the number of hours that the temperature will be below freezing during one night. Also, a typical high for the days in Houston in February is 65deg Fahrenheit (18deg Celsius). Perhaps once every two or three years, Houston will have a freezing rain or snow fall, but not every year. Snow and freezing temperatures are more common in North Texas, but not several days of temperatures continuously below freezing.

There have been media reports stating this was a 1/30yr event. I do not understand this reference or the context of its use in those reports.  What I do know is that this simple number implies to many people that we should expect an event like this once every 30yrs.  This is incorrect, as this number (1/30yrs) is actually a numerical probability and therefore you could have the event every year, or not have it for 100years, and probability number would still be correct.  Probability statistics can be very misleading.

The point being, it was historically cold.

What caused the power outages?

Short Answer: It was due to a large number of power generating plants stopping generation just when demand was increased due to the freezing temperatures. ERCOT had anticipated needing 62.5GW of power and only about 46GW was being supplied.[Updated]

Longer Answer: The list of generation plants affected included Natural Gas, Coal, Cogeneration, Nuclear and Wind…  pretty much all the types available in Texas.

[Update: find the graphic below from the New York Times, note that power was well supplied on Feb 14, but after much colder temperatures on Feb 15, the available generated power dropped, while demand (not shown) continued.]

In Texas, the generation plants have much of their operational equipment exposed to the elements. When the temperatures dropped, those exposed elements could not function safety, so the plant had to cease operation.  This is particularly true of those stations in Southern Texas.

In areas in the US where this level of freezing occurs more often, the power plants continue to operate (including Wind, Solar, Nuclear and so on… ) with out any problems. So this is really a situation where the power generation simply was not built to operate in the low temperatures we experienced.

Why were the power plants in Texas not ready for this cold weather?

Short Answer: It was decided long ago, that the plants did not need to be winterized to deal with this level of freezing (at least those plants in southern Texas). [Update: This statement is a bit unfair, it can be reasoned that the probability of a freeze this severe would have been evaluated as very low.]

Longer Answer: This one will be a key question that many studies will focus in on. Through ERCOT and PUCT and other agencies [Updated], the design and operational guidelines are established for power generation companies.  In short, the requirement for the generation plants operate in these low temperatures was not implemented.

[Update: There are in fact several different groups involved in the power system of Texas, key point here is that the generator plants did not have the requirement to be ready to operate in the low temperatures encountered.]

NOTE: I will presume that not requiring the lower temperature operations, would result in lower costs for power in the State. As you may know, Texas as some of the lowest electrical pricing in the US, while having the largest amount of Wind in the US, and a steady decrease year on year of GHG per GDP (lowering of C02 emissions).

Why was there a water shortage or access problems?

Short Answer: Two reasons; 1) loss of power at the local water plant, 2) drop in pressure in local systems which affected the operation of the disinfection within those water systems.

Longer Answer: The Water system in Texas is managed by local Municipal Utility Districts (MUD). Some of these are large with >100k of users, and many are very small with less than <100 users. There are many regulations and operational requirements for water supply to protect you the consumer and ensure you have quality water.  The water systems are set up with clear requirements for amount of volume and maintaining disinfection. 

Loss of power is usually offset by local backup generators. It is not clear why or how many MUD systems were affected by loss of power due to lack of backup or backups that failed.

Many more MUD systems were affected by loss of pressure, this due to pump failures, but more often with water mains bursting (due to a freeze in some part of the piping).  Water can be rerouted, but this affects pressure and can result in the boil water orders we have seen throughout the State.

Who's fault is all of this?

[Update: Ok fault is a strong word, with so many reading this... lets instead talk about responsibility.]

Short Answer: As with most major failures, there have been many things that have gone wrong… and with multiple groups and agencies within the Texas Power Grid, each will have to review the roles they played.

Longer Answer: There will be many questions and potential changes needed at ERCOT to be sure. However, in my opinion, they are not solely responsible.

There has been much made of power outages in 2010, where studies found that generation plants were not 'winterized', which means they could not operate in the low temperatures in 2010. Since that time, (I cannot confirm) there has not seemed to be significant changes to the generation plants to increase their ability to operate in lower temperatures.

What will be interesting is to ask is;

• Despite the disruption, will Texans be willing to pay more for power, to ensure the power grid will operate better in future rare deep freeze events?
• What utilities continued to work during this situation and which did not? Hint, data centers seemed to run unaffected, as did most medical, and airport systems (at least they had power).  What can we learn from those systems?
• Why did cell coverage drop with the power outages? [this one is my personal beef]

How bad is it in Texas?

Short Answer: Bad. By most measures this was a very serious event.

Longer Answer: During the worst of the blackouts, 60% of the state was without power (18million people); at the peak of the water issues, I believe the number is about 6million people affected. [Note approximately 30million population in TX, estimated by Google]

There have been deaths and there have been fires, so for some people this has been devastating. There is a huge number of homes with burst pipes, perhaps 20% (not a proper survey) which would mean about 2 million homes that need repair.   For reference, there are estimates that 150,000 homes were affected by Hurricane Harvey. To be clear, most of the homes with burst pipes will have much less damage than those affected by Harvey.

Opinion: Putting much of the above in perspective globally or personally, if that is possible, most of those in my network of contacts had a hard week. But, most will be fully back to normal today with only a loss of a week of school or work.  For a much smaller number, they have had much harder time. I am not comfortable that the national media have gotten that balance correct, instead focusing only on those stories of major loss. This event will not be comparable to Harvey for loss of property, loss of life or cost to recover. I suspect much of Texas will be fully operational within a week of the temperatures returning to normal for this time of year, while much of Sothern Texas took a year to recover from Harvey. (We will see if I am right, I could be way off on the number of heavily damaged homes.)

[Update: Again, my opinion above, which is only related to media general coverage. There are defiantly hundreds if not thousands of Texans, and those in other Sothern States who have and are still suffering. See the links below for ideas to help.]

How did you make out during the week? Did you lose power? Water? How did you stay warm?

Short Answer: We did ok, lost power for 50hrs or so, had water but had to boil it, we had to use the gas stove top to provide some heat to keep the house from freezing.

Longer Answer:  We lost power and ALL communications (cell and land line) for about 50hrs between Monday and Wednesday, (had sporadic power until Friday). With the stove top on full (with a CO monitor) we kept the house above 50deg F, I had a digital thermometer that I used to check each room in the house. We did not have a pipe break, but we have very limited piping in our attic (many households to have a lot of piping in the attic).  We did have a leak, but it turned out to be related to ice buildup on the roof, resulting in rain overtopping the roof flashing and running through the siding.

While the roads were bad and DOT asked people not to drive, we walked to locations were our cell phones would work (about a mile from the house). Once road travel was better, we drove to locations with cell coverage or by the end of the week to friends that had power and internet.

To Conclude

Bravo if you have read this far! I hope this addresses some of your questions you might have asked.

If you made it through this weather event with minimal inconvenience, consider volunteering or donating to a local charity, as there are definitely those who were deeply affected and need assistance. Consider the Houston Food Bank or the Gulf Coast Regional Blood Center, links below.