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Electric Power Monthly

Data for November 2021 Release Date: January 26, 2022 Next Release Date: February 25, 2022 full reportPDF
SAS Output
Table B.1 Major Disturbances and Unusual Occurrences, Year-to-Date 2021

Year Month Event Date and Time Restoration Date and Time Duration Utility/Power Pool NERC Region Area Affected Type of Disturbance Loss (megawatts) Number of Customers Affected
2021 1 01/02/2021 10:28 AM 01/02/2021 10:29 AM 0 Hours, 1 Minutes Pacific Gas & Electric Co WECC California: Butte County; Electrical System Separation (Islanding) where part or parts of power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-System Operations 8 5803
2021 1 01/04/2021 10:34 AM 01/04/2021 10:49 AM 0 Hours, 15 Minutes FirstEnergy Corp RF Pennsylvania: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 6 3825
2021 1 01/10/2021 10:44 PM 01/13/2021 4:00 PM 65 Hours, 16 Minutes Oncor Electric Delivery Company LLC TRE Texas: Anderson County, Angelina County, Dallas County, Freestone County, Henderson County, Houston County, Leon County, Nacogdoches County, Smith County, Tarrant County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 188000
2021 1 01/11/2021 5:00 AM 01/11/2021 2:22 PM 9 Hours, 22 Minutes American Electric Power - (SPP Reliability Region) SERC Louisiana: Texas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Distribution Interruption Unknown 58000
2021 1 01/12/2021 8:30 PM . . . Hours, . Minutes Snohomish County PUD No 1 WECC Washington: Snohomish County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Transmission Interruption 200 62000
2021 1 01/12/2021 8:46 PM 01/13/2021 4:00 PM 19 Hours, 14 Minutes Portland General Electric Co WECC Oregon: Clackamas County, Multnomah County, Washington County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 94231
2021 1 01/12/2021 11:49 PM 01/14/2021 2:00 PM 38 Hours, 11 Minutes Seattle City Light, Sytem Control Center WECC Washington: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Distribution Interruption 150 70000
2021 1 01/12/2021 11:50 PM 01/15/2021 1:00 PM 61 Hours, 10 Minutes Puget Sound Energy WECC Washington: Kitsap County, Thurston County, King County, Pierce County, Skagit County, Whatcom County; Electrical System Separation (Islanding) where part or parts of power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-Severe Weather 100 320000
2021 1 01/13/2021 3:43 AM 01/13/2021 4:00 PM 12 Hours, 17 Minutes Avista Corp WECC Washington: Idaho: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 185 70417
2021 1 01/19/2021 2:48 AM 01/20/2021 11:41 AM 32 Hours, 53 Minutes Pacific Gas & Electric Co WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 411 124888
2021 1 01/19/2021 9:31 AM 01/21/2021 2:36 PM 53 Hours, 5 Minutes Southern California Edison Co WECC California: Kern County, Los Angeles County, Riverside County, San Bernardino County, Ventura County, Orange County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 173746
2021 1 01/26/2021 8:49 PM 01/28/2021 9:14 PM 48 Hours, 25 Minutes Pacific Gas & Electric Co WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 841 255715
2021 2 02/01/2021 11:25 PM 02/02/2021 1:12 AM 1 Hours, 47 Minutes American Electric Power - Texas TRE Texas: Kleberg County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 13 6102
2021 2 02/02/2021 9:25 AM 02/03/2021 11:38 AM 26 Hours, 13 Minutes Western Area Power Administration - Upper Great Plains Region MRO South Dakota: Hughes County; Electrical System Separation (Islanding) where part or parts of power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-Severe Weather/Transmission Interruption 5 3
2021 2 02/02/2021 12:34 PM 02/02/2021 3:43 PM 3 Hours, 9 Minutes Western Area Power Administration - Upper Great Plains Region MRO South Dakota: Hughes County; Electrical System Separation (Islanding) where part or parts of power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-Severe Weather/Transmission Interruption 5 4
2021 2 02/03/2021 2:22 PM 02/04/2021 10:32 PM 32 Hours, 10 Minutes Montana-Dakota Utilities Co MRO North Dakota: Logan County, Emmons County, McIntosh County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 7 1400
2021 2 02/06/2021 6:50 AM 02/06/2021 2:43 PM 7 Hours, 53 Minutes Duke Energy Midwest RF Ohio: Kentucky: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 2 02/08/2021 7:04 AM 02/08/2021 2:10 PM 7 Hours, 6 Minutes Minnesota Power MRO Minnesota: St. Louis County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 2 02/09/2021 10:51 AM . . . Hours, . Minutes Duke Energy Progress SERC North Carolina: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 2 02/10/2021 3:00 PM 02/23/2021 3:00 PM 312 Hours, 0 Minutes Oncor Electric Delivery Company LLC TRE Texas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 2000000
2021 2 02/11/2021 8:30 AM 02/22/2021 9:00 AM 264 Hours, 30 Minutes Prairie Power, Inc. SERC Illinois: Scott County; Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency Unknown Unknown
2021 2 02/11/2021 1:00 PM . . . Hours, . Minutes Sunflower Electric Power Corp MRO Kansas: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 0 0
2021 2 02/11/2021 7:21 PM 02/11/2021 9:20 PM 1 Hours, 59 Minutes Public Service Company of Colorado WECC Colorado: Morgan County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 2 02/12/2021 3:30 PM 02/22/2021 7:30 AM 232 Hours, 0 Minutes ERCOT TRE Texas: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency Unknown Unknown
2021 2 02/12/2021 9:00 PM 02/20/2021 5:15 PM 188 Hours, 15 Minutes Portland General Electric Co WECC Oregon: Clackamas County, Marion County, Polk County, Multnomah County, Washington County, Yamhill County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 300187
2021 2 02/13/2021 8:32 AM 02/14/2021 3:00 PM 30 Hours, 28 Minutes Duke Energy Carolinas SERC South Carolina: North Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 129000
2021 2 02/13/2021 9:56 AM 02/13/2021 11:01 AM 1 Hours, 5 Minutes Bonneville Power Administration WECC Washington: Lewis County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 164 37583
2021 2 02/13/2021 1:30 PM 02/19/2021 9:00 PM 151 Hours, 30 Minutes American Electric Power - (RFC Reliability Region) (8400 Smiths Mill Road, New Albany Ohio 43054) RF West Virginia: Virginia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 55097
2021 2 02/13/2021 1:30 PM 02/20/2021 8:00 AM 162 Hours, 30 Minutes American Electric Power - Texas TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/14/2021 5:30 AM 02/18/2021 10:00 AM 100 Hours, 30 Minutes Oklahoma Municipal Power Authority MRO Oklahoma: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/14/2021 8:30 AM 02/19/2021 6:00 PM 129 Hours, 30 Minutes ERCOT TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/14/2021 8:30 AM 02/19/2021 6:00 PM 129 Hours, 30 Minutes Oncor Electric Delivery Company LLC TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 7214 Unknown
2021 2 02/14/2021 6:00 PM 02/16/2021 10:00 PM 52 Hours, 0 Minutes Empire District Electric Co SERC Missouri: Jasper County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 0 0
2021 2 02/14/2021 7:05 PM . . . Hours, . Minutes Evergy SERC Missouri: Kansas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/14/2021 8:00 PM 02/18/2021 9:28 AM 85 Hours, 28 Minutes Southwest Power Pool, Inc. MRO North Dakota: South Dakota: Nebraska: Kansas: Oklahoma: Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 3000 Unknown
2021 2 02/14/2021 8:21 PM 02/18/2021 9:30 AM 85 Hours, 9 Minutes American Electric Power - (SPP Reliability Region) SERC Arkansas: Louisiana: Texas: Oklahoma: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 461 125484
2021 2 02/14/2021 8:32 PM . . . Hours, . Minutes Lincoln Electric System MRO Nebraska: Lancaster County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 0 0
2021 2 02/15/2021 12:00 AM . . . Hours, . Minutes Entergy Transmission Control Center - North TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 500 Unknown
2021 2 02/15/2021 12:00 AM . . . Hours, . Minutes Entergy - Transmission Operations Engineering TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 500 Unknown
2021 2 02/15/2021 1:20 AM . . . Hours, . Minutes South Texas Electric Coop, Inc TRE Texas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 360 72000
2021 2 02/15/2021 1:20 AM 02/18/2021 12:02 AM 70 Hours, 42 Minutes CenterPoint Energy Houston Electric, LLC TRE Texas: Harris County; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 4966 1390000
2021 2 02/15/2021 1:20 AM 02/18/2021 12:42 AM 71 Hours, 22 Minutes Magic Valley Electric Cooperative, Inc. TRE Texas: Hidalgo County, Cameron County; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather Unknown Unknown
2021 2 02/15/2021 1:20 AM 02/19/2021 9:00 AM 103 Hours, 40 Minutes Oncor Electric Delivery Company LLC TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 7214 Unknown
2021 2 02/15/2021 1:23 AM 02/19/2021 5:30 AM 100 Hours, 7 Minutes ERCOT TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather Unknown Unknown
2021 2 02/15/2021 1:54 AM 02/17/2021 11:56 PM 70 Hours, 2 Minutes TNMP TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 524 Unknown
2021 2 02/15/2021 1:54 AM 02/19/2021 9:00 AM 103 Hours, 6 Minutes Austin Energy TRE Texas: Travis County; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 724 Unknown
2021 2 02/15/2021 2:51 AM 02/19/2021 9:00 AM 102 Hours, 9 Minutes Austin Energy TRE Texas: Travis County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 219306
2021 2 02/15/2021 3:06 AM . . . Hours, . Minutes CPS Energy TRE Texas: Bexar County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 154000
2021 2 02/15/2021 5:00 AM 02/17/2021 4:00 PM 59 Hours, 0 Minutes Arkansas Electric Coop Corp SERC Arkansas: Pulaski County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 5:27 AM 02/18/2021 8:18 AM 74 Hours, 51 Minutes ERCOT TRE Texas: Total generation loss, within one minute of: greater than or equal to 2,000 Megawatts in the Eastern or Western Interconnection or greater than or equal to 1,400 Megawatts in the ERCOT Interconnection.-Severe Weather Unknown Unknown
2021 2 02/15/2021 5:36 AM . . . Hours, . Minutes Entergy Transmission Control Center - South TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 300 Unknown
2021 2 02/15/2021 5:36 AM . . . Hours, . Minutes Entergy - Transmission Operations Engineering TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 300 Unknown
2021 2 02/15/2021 5:40 AM 02/16/2021 1:11 PM 31 Hours, 31 Minutes MISO TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 800 Unknown
2021 2 02/15/2021 6:45 AM . . . Hours, . Minutes Entergy Corp TRE Texas: Arkansas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown Unknown
2021 2 02/15/2021 6:51 AM 02/16/2021 1:19 PM 30 Hours, 28 Minutes Oklahoma Gas & Electric Co MRO Oklahoma: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 350 200000
2021 2 02/15/2021 7:00 AM 02/18/2021 9:00 AM 74 Hours, 0 Minutes Oklahoma Gas & Electric Co MRO Oklahoma: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 0 0
2021 2 02/15/2021 7:52 AM 02/17/2021 2:15 PM 54 Hours, 23 Minutes Bluebonnet Electric Coop, Inc TRE Texas: Austin County, Bastrop County, Burleson County, Caldwell County, Colorado County, Fayette County, Gonzales County, Guadalupe County, Hays County, Lee County, Milam County, Travis County, Washington County, Williamson County; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 107 25000
2021 2 02/15/2021 8:50 AM 02/18/2021 9:30 AM 72 Hours, 40 Minutes Sunflower Electric Power Corp MRO Kansas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 9:10 AM . . . Hours, . Minutes Southwestern Public Service TRE Texas: Randall County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 0 0
2021 2 02/15/2021 10:00 AM . . . Hours, . Minutes Lincoln Electric System MRO Nebraska: Lancaster County; Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 613 Unknown
2021 2 02/15/2021 10:24 AM 02/18/2021 9:52 AM 71 Hours, 28 Minutes Lubbock Power & Light TRE Texas: Lubbock County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 116 29942
2021 2 02/15/2021 12:18 PM 02/15/2021 1:22 PM 1 Hours, 4 Minutes Evergy SERC Missouri: Kansas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather Unknown Unknown
2021 2 02/15/2021 1:00 PM 02/20/2021 10:00 AM 117 Hours, 0 Minutes Southwestern Public Service Company TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather Unknown 175000
2021 2 02/15/2021 2:00 PM 02/15/2021 6:00 PM 4 Hours, 0 Minutes Louisiana Generating LLC SERC Louisiana: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency Unknown Unknown
2021 2 02/15/2021 3:00 PM 02/19/2021 10:00 AM 91 Hours, 0 Minutes Cleco Power LLC SERC Louisiana: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 5:00 PM 02/15/2021 10:59 PM 5 Hours, 59 Minutes Cooperative Energy SERC Mississippi: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 6:00 PM 02/15/2021 11:55 PM 5 Hours, 55 Minutes Entergy Services, Inc. TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 6:00 PM 02/15/2021 11:59 PM 5 Hours, 59 Minutes Entergy Services, Inc. TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/15/2021 6:00 PM 02/15/2021 11:59 PM 5 Hours, 59 Minutes Louisiana Generating LLC SERC Louisiana: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations Unknown Unknown
2021 2 02/15/2021 7:48 PM 02/18/2021 10:30 AM 62 Hours, 42 Minutes Oklahoma Municipal Power Authority MRO Oklahoma: Kay County; Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 0 Unknown
2021 2 02/16/2021 1:00 AM 02/16/2021 9:28 PM 20 Hours, 28 Minutes American Electric Power - (RFC Reliability Region) (8400 Smiths Mill Road, New Albany Ohio 43054) SERC Kentucky: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 54167
2021 2 02/16/2021 4:26 AM . . . Hours, . Minutes Entergy Transmission Control Center - South TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 300 Unknown
2021 2 02/16/2021 5:30 AM 02/16/2021 2:00 PM 8 Hours, 30 Minutes Midcontinent Independent System Operator SERC Louisiana: Texas: Illinois: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 1420 Unknown
2021 2 02/16/2021 6:10 AM . . . Hours, . Minutes Ameren Illinois Company SERC Missouri: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather/Transmission Interruption 130 Unknown
2021 2 02/16/2021 6:24 AM 02/16/2021 10:41 AM 4 Hours, 17 Minutes Louisiana Generating LLC SERC Louisiana: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-System Operations 100 18150
2021 2 02/16/2021 6:48 AM . . . Hours, . Minutes Entergy - Transmission Operations Engineering SERC Louisiana: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 360 Unknown
2021 2 02/16/2021 6:48 AM . . . Hours, . Minutes Entergy Transmission Control Center - South SERC Louisiana: Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 402 Unknown
2021 2 02/16/2021 7:03 AM 02/20/2021 10:00 PM 110 Hours, 57 Minutes Evergy MRO Kansas: Missouri: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather Unknown 222000
2021 2 02/16/2021 7:17 AM 02/16/2021 10:08 AM 2 Hours, 51 Minutes Southwestern Public Service TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 168 840000
2021 2 02/16/2021 7:20 AM 02/16/2021 10:02 AM 2 Hours, 42 Minutes Omaha Public Power District MRO Nebraska: Douglas County, Burt County, Washington County, Dodge County, Colfax County, Saunders County, Sarpy County, Cass County, Otoe County, Johnson County, Nemaha County, Pawnee County, Richardson County; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 126 81100
2021 2 02/16/2021 7:22 AM 02/16/2021 8:00 AM 0 Hours, 38 Minutes Cleco Power LLC SERC Louisiana: Allen Parish, St. Landry Parish, Evangeline Parish; Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 153 Unknown
2021 2 02/16/2021 9:31 AM 02/16/2021 10:27 AM 0 Hours, 56 Minutes Nebraska Public Power District MRO Nebraska: Custer County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 31 Unknown
2021 2 02/16/2021 4:40 PM 02/20/2021 12:00 AM 79 Hours, 20 Minutes Ameren Illinois Company SERC Missouri: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/16/2021 5:35 PM 02/17/2021 12:00 AM 6 Hours, 25 Minutes Cooperative Energy SERC Mississippi: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/16/2021 5:35 PM 02/17/2021 12:00 AM 6 Hours, 25 Minutes Lafayette Public Power Auth SERC Louisiana: Lafayette Parish; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/16/2021 6:19 PM . . . Hours, . Minutes Entergy - Transmission Operations Engineering SERC Arkansas: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption Unknown Unknown
2021 2 02/16/2021 6:35 PM 02/17/2021 1:00 AM 6 Hours, 25 Minutes Entergy Services, Inc. TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Fuel Supply Deficiency Unknown Unknown
2021 2 02/16/2021 6:35 PM 02/17/2021 1:00 AM 6 Hours, 25 Minutes Louisiana Generating LLC SERC Louisiana: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations Unknown Unknown
2021 2 02/16/2021 7:40 PM 02/17/2021 1:00 AM 5 Hours, 20 Minutes Entergy Services, Inc. TRE Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 538 Unknown
2021 2 02/16/2021 7:43 PM 02/16/2021 9:41 PM 1 Hours, 58 Minutes Midcontinent Independent System Operator SERC Louisiana: Arkansas: Texas: Mississippi: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 700 Unknown
2021 2 02/17/2021 9:00 AM 02/19/2021 9:00 AM 48 Hours, 0 Minutes Sunflower Electric Power Corp MRO Kansas: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency Unknown Unknown
2021 2 02/17/2021 10:30 AM 02/17/2021 6:04 PM 7 Hours, 34 Minutes Duke Energy Progress SERC North Carolina: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 2 02/17/2021 5:00 PM 02/17/2021 10:00 PM 5 Hours, 0 Minutes Lafayette Public Power Auth SERC Louisiana: Lafayette Parish; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 400 67000
2021 2 02/17/2021 5:00 PM 02/17/2021 10:00 PM 5 Hours, 0 Minutes Cooperative Energy SERC Mississippi: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/17/2021 6:00 PM 02/17/2021 11:00 PM 5 Hours, 0 Minutes Entergy Services, Inc. TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather Unknown Unknown
2021 2 02/17/2021 6:00 PM 02/17/2021 11:00 PM 5 Hours, 0 Minutes Louisiana Generating LLC SERC Louisiana: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations Unknown Unknown
2021 2 02/19/2021 6:48 AM . . . Hours, . Minutes Entergy - Transmission Operations Engineering SERC Louisiana: Texas: Firm load shedding of 100 Megawatts or more implemented under emergency operational policy.-Severe Weather 402 Unknown
2021 3 03/01/2021 10:45 PM 03/02/2021 6:35 PM 19 Hours, 50 Minutes ISO New England NPCC Connecticut: Massachusetts: New Hampshire: Maine: Rhode Island: Vermont: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 69260
2021 3 03/06/2021 3:21 AM 03/06/2021 4:07 AM 0 Hours, 46 Minutes Pacific Gas & Electric Co WECC California: Tuolumne County; Electrical System Separation (Islanding) where part or parts of power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-Severe Weather 22 24000
2021 3 03/17/2021 6:15 AM 03/18/2021 12:00 PM 29 Hours, 45 Minutes Oncor Electric Delivery Company LLC TRE Texas: Dallas County, Tarrant County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 148000
2021 3 03/17/2021 6:27 AM 03/17/2021 8:27 AM 2 Hours, 0 Minutes FirstEnergy Corp RF Pennsylvania: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 43 7381
2021 3 03/29/2021 11:06 AM . . . Hours, . Minutes ISO New England NPCC Connecticut: Massachusetts: Maine: Vermont: Rhode Island: New Hampshire: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 70000
2021 3 03/30/2021 4:18 PM 03/30/2021 8:21 PM 4 Hours, 3 Minutes American Electric Power - Texas TRE Texas: Hidalgo County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 4 04/13/2021 4:49 PM 04/13/2021 8:30 PM 3 Hours, 41 Minutes ERCOT TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 0 0
2021 4 04/21/2021 8:31 PM 04/21/2021 9:35 PM 1 Hours, 4 Minutes Northern States Power Co MRO Minnesota: Dakota County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 4 04/22/2021 5:15 AM . . . Hours, . Minutes California Department of Water Resources WECC California: Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 0 0
2021 4 04/24/2021 9:00 PM 04/25/2021 10:43 AM 13 Hours, 43 Minutes Southern Company SERC Alabama: Calhoun County; Georgia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 137 18860
2021 5 05/04/2021 3:45 PM 05/05/2021 10:00 AM 18 Hours, 15 Minutes Entergy Corp SERC Arkansas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 104027
2021 5 05/04/2021 6:06 PM 05/05/2021 5:48 PM 23 Hours, 42 Minutes Southern Company SERC Mississippi: Alabama: Georgia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 175 24457
2021 5 05/06/2021 5:00 PM 05/06/2021 5:15 PM 0 Hours, 15 Minutes Empire District Electric Co SERC Missouri: Jasper County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations 0 0
2021 5 05/18/2021 11:25 PM 05/19/2021 8:30 PM 21 Hours, 5 Minutes CenterPoint Energy TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 125000
2021 5 05/20/2021 10:06 AM 05/20/2021 1:45 PM 3 Hours, 39 Minutes Florida Power & Light SERC Florida: Brevard County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 35000
2021 5 05/27/2021 6:51 PM 05/28/2021 3:56 PM 21 Hours, 5 Minutes Southern California Edison Co WECC California: Nevada: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 5 05/28/2021 9:24 PM 05/28/2021 9:25 PM 0 Hours, 1 Minutes JEA SERC Florida: Duval County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 1850 10000
2021 6 06/06/2021 2:57 PM 06/06/2021 4:00 PM 1 Hours, 3 Minutes Duke Energy Midwest RF Indiana: Clay County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption Unknown 0
2021 6 06/07/2021 1:26 PM 06/07/2021 1:27 PM 0 Hours, 1 Minutes Vistra Energy TRE Texas: Somervell County, Ellis County; Total generation loss, within one minute of: greater than or equal to 2,000 Megawatts in the Eastern or Western Interconnection or greater than or equal to 1,400 Megawatts in the ERCOT Interconnection.-Generation Inadequacy 1435 0
2021 6 06/07/2021 10:27 PM 06/08/2021 12:33 AM 2 Hours, 6 Minutes Western Area Power Administration - Upper Great Plains Region MRO Minnesota: North Dakota: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Severe Weather/Transmission Interruption 23 1
2021 6 06/10/2021 10:28 PM 06/10/2021 11:07 PM 0 Hours, 39 Minutes Board of Public Utilities, Kansas City MRO Kansas: Wyandotte County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 90 9800
2021 6 06/11/2021 3:26 AM 06/11/2021 3:48 AM 0 Hours, 22 Minutes Western Area Power Administration - Upper Great Plains Region - (NCR01036) MRO South Dakota: Brown County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Severe Weather/Transmission Interruption 0 0
2021 6 06/14/2021 12:15 PM 06/18/2021 7:00 PM 102 Hours, 45 Minutes ERCOT TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations Unknown Unknown
2021 6 06/14/2021 12:55 PM 06/18/2021 7:00 PM 102 Hours, 5 Minutes Oncor Electric Delivery Company LLC TRE Texas: Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-System Operations Unknown Unknown
2021 6 06/16/2021 10:40 AM 06/16/2021 10:43 AM 0 Hours, 3 Minutes Entergy - Transmission Operations Engineering SERC Louisiana: West Baton Rouge Parish; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 7 1841
2021 6 06/19/2021 6:54 PM 06/19/2021 9:01 PM 2 Hours, 7 Minutes Pacific Gas & Electric Co WECC California: Alameda County; Loss of electric service to more than 50,000 customers for 1 hour or more.-System Operations 93 51806
2021 6 06/21/2021 5:14 AM 06/21/2021 7:00 PM 13 Hours, 46 Minutes Detroit Edison Co RF Michigan: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 151852
2021 6 06/24/2021 3:34 AM 06/24/2021 5:07 AM 1 Hours, 33 Minutes Pacific Gas & Electric Co WECC California: Plumas County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system.-Transmission Interruption 36 7621
2021 6 06/28/2021 11:22 AM . . . Hours, . Minutes Duke Energy Progress SERC North Carolina: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 6 06/28/2021 1:20 PM . . . Hours, . Minutes Avista Corp WECC Washington: Spokane County, Stevens County, Lincoln County, Adams County, Whitman County; Idaho: Kootenai County, Bonner County, Shoshone County, Boundary County, Benewah County, Latah County, Nez Perce County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System.-Severe Weather 44 Unknown
2021 6 06/29/2021 4:00 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Oakland County, Macomb County, Wayne County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 53000
2021 6 06/30/2021 6:50 PM . . . Hours, . Minutes ISO New England NPCC Connecticut: Massachusetts: Rhode Island: Vermont: New Hampshire: Maine: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather Unknown 53103
2021 7 07/06/2021 7:41 PM 07/06/2021 9:50 PM 2 Hours, 9 Minutes Jersey Central Power & Lt Co RF Ohio: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather/Transmisison Interruption Unknown 136827
2021 7 07/07/2021 3:30 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Macomb County, Oakland County, Monroe County, Livingston County, St. Clair County, Washtenaw County, Wayne County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 90000
2021 7 07/10/2021 12:00 AM 07/11/2021 4:00 PM 40 Hours, 0 Minutes Omaha Public Power District MRO Nebraska: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 188000
2021 7 07/10/2021 12:30 AM 07/10/2021 5:00 AM 4 Hours, 30 Minutes Southwest Power Pool, Inc. MRO/SERC Missouri: Nebraska: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather/Transmisison Interruption Unknown 212500
2021 7 07/10/2021 12:30 AM 07/10/2021 5:00 AM 4 Hours, 30 Minutes Southwest Power Pool, Inc. MRO/SERC Nebraska: Missouri: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather/Transmisison Interruption Unknown 211500
2021 7 07/10/2021 1:55 AM 07/10/2021 1:56 AM 0 Hours, 1 Minutes Ameren Illinois Company SERC Missouri: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 52000
2021 7 07/14/2021 2:15 PM 07/14/2021 2:16 PM 0 Hours, 1 Minutes Pacific Gas & Electric Co WECC California: Plumas County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather/Transmisison Interruption 35 11000
2021 7 07/21/2021 2:45 PM 07/22/2021 12:00 PM 21 Hours, 15 Minutes Exelon Corporation/PECO RF Pennsylvania: Bucks County, Chester County, Delaware County, Montgomery County, Philadelphia County, York County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 81503
2021 7 07/23/2021 8:20 AM 07/23/2021 10:45 AM 2 Hours, 25 Minutes Dominion Energy VA RF/SERC Virginia: West Virginia: Complete loss of monitoring or control capability at its staffed Bulk Electric System control center for 30 continuous minutes or more.-System Operations 0 0
2021 7 07/24/2021 8:30 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Wayne County, Oakland County, Livingston County, Macomb County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 225949
2021 7 07/28/2021 12:54 PM 07/28/2021 3:42 PM 2 Hours, 48 Minutes Central Maine Power Co NPCC Maine: Complete loss of monitoring or control capability at its staffed Bulk Electric System control center for 30 continuous minutes or more.-System Operations 0 0
2021 7 07/30/2021 8:02 AM 07/30/2021 9:34 AM 1 Hours, 32 Minutes WEC Energy Group (WEPCO, WPSC, UMERC, WEP-MIUP) MRO Wisconsin: Complete loss of monitoring or control capability at its staffed Bulk Electric System control center for 30 continuous minutes or more.-Cyber Event 0 0
2021 8 08/01/2021 11:37 PM 08/02/2021 12:00 AM 0 Hours, 23 Minutes Pacific Gas & Electric Co WECC California: Humboldt County, Trinity County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather 95 65888
2021 8 08/02/2021 12:18 AM 08/02/2021 10:47 AM 10 Hours, 29 Minutes LCRA TSC TRE Texas: Hays County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Severe Weather/Transmission Interruption 24 9400
2021 8 08/02/2021 6:23 AM 08/02/2021 3:55 PM 9 Hours, 32 Minutes LCRA TSC TRE Texas: Hays County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Severe Weather/Transmission Interruption 43 19000
2021 8 08/03/2021 4:35 AM 08/03/2021 5:28 AM 0 Hours, 53 Minutes Bonneville Power Administration WECC Oregon: Linn County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 4 Unknown
2021 8 08/10/2021 8:00 PM . . . Hours, . Minutes WEC Energy Group (WEPCO, WPSC, UMERC, WEP-MIUP) RF/SERC Wisconsin: Waukesha County, Milwaukee County, Kenosha County, Racine County, Washington County, Ozaukee County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 233000
2021 8 08/10/2021 8:30 PM 08/11/2021 7:00 PM 22 Hours, 30 Minutes ComEd RF/SERC Illinois: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 318761
2021 8 08/10/2021 10:30 PM 08/13/2021 4:38 PM 66 Hours, 8 Minutes Consumers Energy Co RF Michigan: Allegan County, Antrim County, Barry County, Benzie County, Branch County, Calhoun County, Clare County, Clinton County, Crawford County, Eaton County, Genesee County, Gladwin County, Grand Traverse County, Gratiot County, Hillsdale County, Ingham County, Ionia County, Isabella County, Jackson County, Kalamazoo County, Kalkaska County, Kent County, Lake County, Leelanau County, Manistee Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 372600
2021 8 08/11/2021 3:35 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Huron County, Macomb County, Lapeer County, Macomb County, Monroe County, Oakland County, St. Clair County, Tuscola County, Wayne County, Washtenaw County, Livingston County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 700000
2021 8 08/11/2021 7:12 PM 08/11/2021 9:49 PM 2 Hours, 37 Minutes Cleveland Electric Illum Co RF Ohio: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 92109
2021 8 08/12/2021 6:57 PM 08/13/2021 6:00 AM 11 Hours, 3 Minutes Ameren Missouri RF/SERC Illinois: Missouri: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 101000
2021 8 08/17/2021 7:15 PM 08/18/2021 5:45 PM 22 Hours, 30 Minutes Pacific Gas & Electric Co WECC California: Butte County, Colusa County, Glenn County, Lake County, Lassen County, Mendocino County, Napa County, Plumas County, Shasta County, Sierra County, Solano County, Sonoma County, Tehama County, Trinity County, Yolo County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather 234 71000
2021 8 08/21/2021 10:14 AM 08/21/2021 10:52 AM 0 Hours, 38 Minutes Idaho Power Company WECC Idaho: Elmore County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather 0 418
2021 8 08/22/2021 12:11 PM 08/23/2021 4:30 PM 28 Hours, 19 Minutes ISO New England NPCC Connecticut: Massachusetts: Maine: Rhode Island: Vermont: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 28134
2021 8 08/24/2021 5:00 PM 08/26/2021 2:07 PM 45 Hours, 7 Minutes Consumers Energy Co RF Michigan: Arenac County, Bay County, Clare County, Genesee County, Gladwin County, Gratiot County, Isabella County, Iosco County, Kalamazoo County, Kent County, Barry County, Missaukee County, Montcalm County, Muskegon County, Newaygo County, Mecosta County, Midland County, Saginaw County, Ottawa County, Van Buren County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 84987
2021 8 08/24/2021 9:37 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Huron County, Lapeer County, Macomb County, Monroe County, Oakland County, St. Clair County, Wayne County, Washtenaw County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 65000
2021 8 08/29/2021 9:32 AM 08/29/2021 9:32 PM 12 Hours, 0 Minutes Entergy - Transmission Operations Engineering SERC Louisiana: Pointe Coupee Parish; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption Unknown Unknown
2021 8 08/29/2021 11:30 AM . . . Hours, . Minutes Entergy Corp SERC Louisiana: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown Unknown
2021 8 08/29/2021 5:53 PM . . . Hours, . Minutes Entergy Transmission Control Center - North SERC Louisiana: Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather Unknown Unknown
2021 8 08/29/2021 6:00 PM 09/03/2021 1:41 PM 115 Hours, 41 Minutes Cleco Power LLC SERC Louisiana: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 91315
2021 8 08/29/2021 6:04 PM 08/31/2021 10:36 PM 52 Hours, 32 Minutes Entergy - Transmission Operations Engineering SERC Louisiana: St. Charles Parish; Complete loss of off-site power (LOOP) affecting a nuclear generating station per the Nuclear Plant Interface Requirements.-Severe Weather Unknown Unknown
2021 8 08/29/2021 8:25 PM . . . Hours, . Minutes Consolidated Edison of New York, Inc. NPCC New York: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 796 0
2021 8 08/29/2021 10:39 PM 09/03/2021 8:38 AM 105 Hours, 59 Minutes Louisiana Generating LLC SERC Louisiana: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 50000
2021 9 09/01/2021 5:30 PM 09/02/2021 2:00 AM 8 Hours, 30 Minutes Exelon Corporation/PECO RF Pennsylvania: Bucks County, Chester County, Delaware County, Montgomery County, Philadelphia County, York County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 252740
2021 9 09/07/2021 5:30 PM 09/09/2021 9:00 AM 39 Hours, 30 Minutes Consumers Energy RF Michigan: Osceola County, Kalamazoo County, Van Buren County, Saginaw County, Arenac County, Lake County, Clare County, Mecosta County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 80000
2021 9 09/07/2021 8:00 PM 09/09/2021 7:00 AM 35 Hours, 0 Minutes Detroit Edison Co RF Michigan: Wayne County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 60000
2021 9 09/08/2021 12:15 PM 09/08/2021 12:38 PM 0 Hours, 23 Minutes Western Area Power Administration - Upper Great Plains Region - (NCR01036) MRO North Dakota: Cass County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 37 1
2021 9 09/09/2021 5:00 PM 09/09/2021 8:00 PM 3 Hours, 0 Minutes NV Energy WECC Nevada: Clark County, Washoe County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System-System Operations 8000 1300000
2021 9 09/10/2021 1:55 AM 09/10/2021 2:04 AM 0 Hours, 9 Minutes Duke Energy Florida SERC Florida: Citrus County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Severe Weather 75 Unknown
2021 9 09/10/2021 7:20 AM 09/10/2021 9:05 AM 1 Hours, 45 Minutes Pacific Gas and Electric WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather 89 59649
2021 9 09/10/2021 11:17 AM 09/10/2021 11:19 AM 0 Hours, 2 Minutes Western Area Power Administration - Upper Great Plains Region - (NCR01036) MRO North Dakota: McKenzie County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 6 1
2021 9 09/13/2021 12:18 PM 09/13/2021 1:15 PM 0 Hours, 57 Minutes Bonneville Power Administration WECC Washington: Skagit County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 9 09/13/2021 6:00 PM 09/14/2021 12:49 AM 6 Hours, 49 Minutes CenterPoint Energy TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 66589
2021 9 09/13/2021 11:59 PM . . . Hours, . Minutes CenterPoint Energy TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 204280
2021 9 09/14/2021 12:35 AM 09/18/2021 7:20 PM 114 Hours, 45 Minutes CenterPoint Energy TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather 1905 705415
2021 9 09/14/2021 7:36 AM 09/15/2021 1:48 AM 18 Hours, 12 Minutes ERCOT TRE Texas: Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather 0 Unknown
2021 9 09/14/2021 7:52 AM 09/14/2021 10:44 PM 14 Hours, 52 Minutes ERCOT TRE Texas: Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Severe Weather 0 Unknown
2021 9 09/16/2021 2:49 PM 09/16/2021 8:02 PM 5 Hours, 13 Minutes American Electric Power - (SPP Reliability Region) MRO/SERC Oklahoma: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 100 4000
2021 9 09/16/2021 2:49 PM 09/16/2021 8:02 PM 5 Hours, 13 Minutes American Electric Power - (SPP Reliability Region) MRO/SERC Oklahoma: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 100 4000
2021 9 09/17/2021 3:00 AM 09/18/2021 10:00 PM 43 Hours, 0 Minutes Northern States Power Co MRO Minnesota: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 82000
2021 9 09/17/2021 11:00 PM 09/19/2021 12:00 PM 37 Hours, 0 Minutes Puget Sound Energy WECC Washington: Pierce County, Whatcom County, Skagit County, King County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather/Transmission Interruption Unknown 87000
2021 9 09/22/2021 5:17 PM . . . Hours, . Minutes Detroit Edison Co RF Michigan: Lenawee County, Livingston County, Genesee County, Tuscola County, Huron County, Sanilac County, Lapeer County, St. Clair County, Macomb County, Oakland County, Washtenaw County, Wayne County, Monroe County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 136000
2021 9 09/28/2021 1:44 PM 09/28/2021 1:56 PM 0 Hours, 12 Minutes Gridforce Energy Management LLC SERC Kentucky: Henderson County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-Transmission Interruption 20 5000
2021 10 10/10/2021 10:15 PM 10/12/2021 5:00 PM 42 Hours, 45 Minutes Oncor Electric Delivery Company LLC TRE Texas: Collin County, Dallas County, Denton County, Ellis County, Hunt County, Johnson County, Palo Pinto County, Tarrant County, Wichita County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 110000
2021 10 10/11/2021 2:22 PM 10/11/2021 8:30 PM 6 Hours, 8 Minutes Pacific Gas & Electric Co WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather 126 84000
2021 10 10/16/2021 2:16 PM 10/16/2021 6:41 PM 4 Hours, 25 Minutes Bonneville Power Administration WECC Oregon: Lane County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption Unknown Unknown
2021 10 10/19/2021 3:34 PM 10/19/2021 4:26 PM 0 Hours, 52 Minutes FirstEnergy Corp RF Ohio: Summit County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 42 1
2021 10 10/24/2021 7:00 AM 10/26/2021 9:30 PM 62 Hours, 30 Minutes Puget Sound Energy WECC Washington: King County, Pierce County, Skagit County, Thurston County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 233000
2021 10 10/24/2021 8:55 AM 10/25/2021 6:15 PM 33 Hours, 20 Minutes Pacific Gas & Electric Co WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather 116 59000
2021 10 10/27/2021 2:25 AM 10/29/2021 8:37 AM 54 Hours, 12 Minutes ISO New England NPCC Connecticut: Maine: Massachusetts: New Hampshire: Rhode Island: Vermont: Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 169000
2021 10 10/27/2021 5:57 PM 10/28/2021 4:49 PM 22 Hours, 52 Minutes Entergy - Transmission Operations Engineering SERC Louisiana: Ascension Parish; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 0 0
2021 10 10/28/2021 12:47 PM 10/28/2021 1:05 PM 0 Hours, 18 Minutes Western Area Power Administration - Upper Great Plains Region - (NCR01036) WECC Montana: Valley County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 20 0
2021 10 10/28/2021 2:15 PM 10/30/2021 8:00 AM 41 Hours, 45 Minutes Oncor Electric Delivery Company LLC TRE Texas: Angelina County, Bell County, Cherokee County, Collin County, Denton County, Dallas County, Ellis County, Hunt County, Johnson County, McLennan County, Nacogdoches County, Smith County, Tarrant County, Travis County, Williamson County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 250000
2021 10 10/28/2021 2:45 PM 10/29/2021 8:30 PM 29 Hours, 45 Minutes CenterPoint Energy TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 130000
2021 11 11/04/2021 9:34 PM 11/04/2021 10:57 PM 1 Hours, 23 Minutes Western Area Power Administration - Upper Great Plains Region - (NCR05467) WECC Montana: Hill County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 44 Unknown
2021 11 11/08/2021 10:53 PM 11/08/2021 11:33 PM 0 Hours, 40 Minutes Puget Sound Energy WECC Washington: King County; Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-System Operations 9 Unknown
2021 11 11/09/2021 6:00 PM 11/09/2021 8:00 PM 2 Hours, 0 Minutes Clarksdale Public Utilities SERC Mississippi: Coahoma County; Public appeal to reduce the use of electricity for purposes of maintaining the continuity of the Bulk Electric System-System Operations Unknown Unknown
2021 11 11/10/2021 9:49 AM 11/10/2021 10:05 AM 0 Hours, 16 Minutes Consolidated Edison of New York, Inc. NPCC New York: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 11 11/10/2021 9:19 PM 11/11/2021 1:19 AM 4 Hours, 0 Minutes Entergy - Transmission Operations Engineering TRE Texas: Brazos County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-Transmission Interruption 0 0
2021 11 11/11/2021 5:52 AM 11/11/2021 6:09 AM 0 Hours, 17 Minutes Entergy - Transmission Operations Engineering TRE Texas: Montgomery County; Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 67 Unknown
2021 11 11/15/2021 11:00 AM 11/17/2021 6:00 AM 43 Hours, 0 Minutes Puget Sound Energy WECC Washington: King County, Kitsap County, Whatcom County, Thurston County, Pierce County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 90000
2021 11 11/24/2021 10:00 AM 11/26/2021 10:21 AM 48 Hours, 21 Minutes Southern California Edison Co WECC California: Riverside County, Ventura County, San Bernardino County, Orange County, Los Angeles County; Loss of electric service to more than 50,000 customers for 1 hour or more-Severe Weather Unknown 81406
2021 11 11/30/2021 6:46 AM 11/30/2021 6:47 AM 0 Hours, 1 Minutes Duke Energy Carolinas SERC North Carolina: South Carolina: Unexpected Transmission loss within its area, contrary to design, of three or more Bulk Electric System Facilities caused by a common disturbance (excluding successful automatic reclosing).-System Operations 0 0
2021 11 11/30/2021 1:47 PM 11/30/2021 2:21 PM 0 Hours, 34 Minutes Pacific Gas & Electric Co WECC California: Electrical System Separation (Islanding) where part or parts of a power grid remain(s) operational in an otherwise blacked out area or within the partial failure of an integrated electrical system-System Operations 10 6000

Note: Customers affected are estimates and are preliminary.
Source: Form OE-417, 'Electric Emergency Incident and Disturbance Report.'