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What Happened During the February 2021 Winter Freeze: A Time-lapse of Electricity Generation by Resource in ERCOT with Hourly Power Plant and Customer Outages

2021 Freeze: Generation by Fuel and Outages



Winter storm Uri struck in February 2021, causing historical, devastating impacts on the Texas power grid, managed by the Electric Reliability Council of Texas (ERCOT). All types of power generating resources experienced outages and derates under extreme cold weather. At the peak of the storm on February 16, over 30% of ERCOT’s winter capacity was offline. ERCOT was forced to issue load shed orders to maintain system stability. This included long periods of extended blackouts across the state, leaving millions of customers in the dark and cold for days.

So let us travel back in time to look at what happened between February 10 and February 28, 2021.

This time-lapse video above shows a side-by-side visualization of ERCOT daily electricity generation by resource (left) and Texas hourly power plant outages and customer outages (right) during the February freeze of 2021.

The left-side chart includes generation by resource at the 15-minute interval and day-ahead load forecast (projected demand). The right-side map illustrates Texas power plant capacity outages at the facility level (bubbles) and customer outages at the county level (filled map in blue shades). Also included are crude oil (green lines) and natural gas (red lines) pipeline infrastructure as well as the ERCOT service area (black line).

Click here for a complete time-lapse of ERCOT daily electric generation by fuel since January 1, 2009.

For more information, see the Center for Energy Studies.