01 The Hour
01:20
Monday 15 February 2021, Texas
Between midnight and twenty-three minutes past one, generator outages on the Texas grid rose from thirty gigawatts to thirty-five. The operator went to its highest emergency alert level and shed a gigawatt of load. Over the following half hour another five gigawatts of generation went, the system frequency dipped below 59.4 hertz, and more than eight gigawatts was shed to hold it up.
None of that is a monetary event. What came next was. A checkout lane is a computer on a line, and it was on the circuits that went out.
02 The Sequence
14 Feb Sunday. Snow and ice blanket large swaths of the country and reach as far south as the Texas Gulf Coast.
15 Feb Monday, 01:20. Energy Emergency Alert Level 3 begins. It stays active until nine in the morning on 19 February. People queue to buy groceries in Houston. As many as five million customers across the country lose power during the day.
16 Feb Tuesday. A grocery store in Dallas has lost power and is open for cash-only sales. Customers use the light from a mobile phone to look into the meat section. Outside, a woman sets down an empty canister to exchange for a full propane tank, two nights into her own outage.
17 Feb Wednesday morning. More than 2.9 million customers in Texas are without power.
17 Feb Wednesday. A store in San Marcos is without power for most of the day and completely out of perishable items, allowing customers to buy only five items from the dry goods section. The line wraps around the building and residents wait up to three hours.
17 Feb Wednesday afternoon. The chain lists 23 stores in Austin and Central Texas as temporarily closed, along with nine in San Antonio, sets purchase limits and shortens hours. Its statement records that the weather event has caused severe disruption in the food supply chain, complicated by power and water outages.
18 Feb Thursday. Shelves are empty, food pantries are running out of supplies, and Texans queue at an Austin store to refill propane tanks.
19 Feb Friday, 09:00. The emergency alert level ends. The outages have taken drinking water with them for thousands in Houston, and the city is distributing water across the metropolitan area.
23 Sep 2021. The joint federal and reliability-corporation inquiry presents preliminary findings: the operator's manual load shed spanned nearly three days.
16 Nov 2021. The final report is issued. The operator ordered a total of 20,000 megawatts of rolling blackouts to prevent grid collapse, the largest manually controlled load shedding event in United States history.
03 The Hidden Dependency
The headline failure was heat and light. Underneath it sat the checkout.
The Dallas store that had lost power stayed open on the Tuesday for cash-only sales, with customers holding phones up to see into the meat section. The San Marcos store went most of the Wednesday without power, had nothing perishable left, and let each customer take five items from the dry goods section while the line went around the building.
Both were still trading. What had gone was the machinery that prices, records and settles a basket. What stood in for it was a person, a limit and a queue. The sources do not establish where a household without notes was to get any that week.
Trade continued at the door on the terms of whoever already had notes in his pocket.
04 What Still Worked
Notes at the Counter
The Dallas store had no power and was still selling, for cash. That is the transaction the week reduced to.
The Stores That Stayed Open
Thirty-two of the chain's stores were listed as temporarily closed on the Wednesday afternoon, out of more than 400 across Texas and Mexico. The rest traded on shortened hours with purchase limits.
Distribution Without Payment
The state comptroller's later account records the Red Cross, food banks and a South Texas grocery chain working together, and in some cases in partnership, to provide services during and after the storm.
05 Contested
Contested Feb 2021
Was it only the generators? The federal inquiry frames the event around outages, derates and failures to start at generating plants, and records 20,000 megawatts of rolling blackouts ordered to prevent grid collapse. A national laboratory study of the same event notes that transmission and distribution equipment can be damaged by extreme cold, that the operator does not publish transmission outage data without the consent of the equipment owners, and that it remains uncertain whether transmission infrastructure outages played a role in the extended blackouts.
06 The Pattern Library
1
When one retail withdrawal channel closes or fails, demand concentrates on whichever channel is left open, and the capacity of that channel sets what a depositor can obtain.
Observed: Northern Rock 2007, Cyprus 2013, India 2016, Greece 2015, United States 1933, Argentina 2001, Lebanon 2019, Worldpay 2026.
2
A currency replacement can require physical modification of each cash dispensing machine before the new notes can be issued, so the machine estate returns to service site by site rather than at once.
Observed: India 2016.
3
Withdrawal limits imposed on a domestic banking system can be written to exempt cards issued outside it, so one machine dispenses under two rules according to where the card was issued.
Observed: Greece 2015.
4
Domestic payment and deposit channels can continue operating while cross-border payment routes fail, with the central bank standing in as the intermediary for payments to and from the country.
Observed: Iceland 2008.
5
When the institutions that convert payment instruments into cash are closed, wages and checks already received cannot be spent, and merchants and carriers extend their own credit in place of the missing conversion.
Observed: United States 1933.
6
A public employer short of the national currency can pay wages in an instrument it issues itself, which then circulates alongside the currency it stands in for.
Observed: Argentina 2001.
7
Withdrawal restrictions can be imposed by individual institutions and their trade association rather than by statute, so the limit differs from bank to bank and no law governs it.
Observed: Lebanon 2019.
8
A cash withdrawal ceiling set in nominal units has to be raised alongside the note denominations that pay it, because the ceiling can only be dispensed in the notes that exist.
Observed: Zimbabwe 2008.
9
A payment outage can hit card authorisation and merchant funding as separate faults, so acceptance at the terminal is restored while the money owed to the merchant arrives a day late under its own incident notice.
Observed: Worldpay 2026.
10
A retailer that loses electricity can go on trading by taking cash and rationing goods by hand, so the counter outlasts the checkout system that normally prices and settles the basket.
Observed: Texas 2021.
Changed today: No existing entry gained Texas 2021. The sources here document card acceptance failing rather than a withdrawal channel, and do not establish where cash could be obtained. Entry 10 added, on a retailer trading through a power failure on cash and a hand-set purchase limit.