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Electric Power Monthly

Data for June 2021 Release Date: August 24, 2021 Next Release Date: September 24, 2021 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 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 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 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 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 5:36 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 5:40 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 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 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 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 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 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 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 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 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 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

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