Texas power grid load shedding in the early morning of 15 February 2021, 0123-0203. Up to an additional ∼24,000 MW net generation was unavailable due to extreme weather. Loss of generation was 52,277 MW (approximately 48.6 percent) at the highest point. Peak load shed was 20,000 MW. Most of the loss was caused by limited gas availability for gas-fired power plants. Graphic: ERCOT
Texas power grid load shedding in the early morning of 15 February 2021, 0123-0203. Up to an additional ∼24,000 MW net generation was unavailable due to extreme weather. Loss of generation was 52,277 MW (approximately 48.6 percent) at the highest point. Peak load shed was 20,000 MW. Most of the loss was caused by limited gas availability for gas-fired power plants. Graphic: ERCOT

25 February 2021 (ERCOT) – [The following report is excerpted from the ERCOT slide presentation, Review of February 2021 Extreme Cold Weather Event (pdf), presented by ERCOT CEO Bill Magness to the Texas Senate Business and Commerce Committee House Joint Committee on State Affairs and Energy Resources on 25 February 2021. –Des]

Overview of Cold Weather Event

  • Record-setting, sub-freezing temperatures, and wind chills across the state.
  • Approximately 48.6% of generation was forced out at the highest point due to the impacts of various extreme weather conditions.
  • Controlled outages were implemented to prevent statewide blackout. Electric demand had to be limited to available generation supply.
  • Local utilities were limited in their ability to rotate outages due to the magnitude of generation unavailability and the number of circuits with critical load.
Chronology of the Texas power grid failure during Winter Storm Uri, 14 February 2021-15 February 2021. Graphic: ERCOT
Chronology of the Texas power grid failure during Winter Storm Uri, 14 February 2021-15 February 2021. Graphic: ERCOT

Key Events (Monday, February 15 – Friday, February 19)

  • More than 16,500 control room calls with generators and transmission owners (normal: ∼5,000/week).
  • Multiple daily coordinating calls between transmission owners and operations management.

Monday, February 15

  • Up to an additional ∼24,000 MW net generation unavailable due to extreme weather; loss of generation was 52,277 MW (approximately 48.6%) at the highest point.
  • 20,000 MW peak load shed.
  • Limited gas availability for gas-fired power plants.
  • Multiple DC-Tie constraints due to neighboring area emergencies.
  • Daily Texas Energy Reliability Council meetings.
Texas power grid capacity outage by fuel type during Winter Storm Uri, 14 February 2021-20 February 2021. Most of the capacity loss was caused by limited gas availability for gas-fired power plants. Graphic: ERCOT
Texas power grid capacity outage by fuel type during Winter Storm Uri, 14 February 2021-20 February 2021. Most of the capacity loss was caused by limited gas availability for gas-fired power plants. Graphic: ERCOT

Tuesday, February 16

  • No net gain in generation as some generators were restored and others became unavailable.
  • Decreased volume of controlled outages during the day, increased for evening peak.

Wednesday, February 17

  • Moderating temperatures allowed reduction in controlled outages, small net gain in generation.

Thursday, February 18

  • Continued gain in generation.
  • 12:42 a.m. – Canceled last controlled outage orders – some outages remained due to ice storm damage; need for manual restoration and return of large industrial facilities.
Total generation capacity of the Texas power grid during the outage caused by Winter Storm Uri, 14 February 2021-19 February 2021. Graphic: ERCOT
Total generation capacity of the Texas power grid during the outage caused by Winter Storm Uri, 14 February 2021-19 February 2021. Graphic: ERCOT

Friday, February 19 (all times approximate)

  • 9 a.m. – Returned to emergency operations level 2
  • 10 a.m. – Returned to emergency operations level 1
  • 10:35 a.m. – Returned to normal operations

[more]

Review of February 2021 Extreme Cold Weather Event