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Electric Power Monthly

Data for April 2020  |  Release date: June 24, 2020  |  Next release: July 24, 2020  |
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SAS Output
Table B.1 Major Disturbances and Unusual Occurrences, Year-to-Date 2020

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
2020 1 . . . . . Hours, . Minutes Entergy Transmission Control Center - South SPP RE Arkansas: 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    
2020 1 . . . . . Hours, . Minutes Southern Company SERC Alabama: Georgia: Mississippi: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 219 30715
2020 1 . . . . . Hours, . Minutes Tennessee Valley Authority SERC Tennessee: 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 4  
2020 1 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC California: Humboldt 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 87 67864
2020 1 . . . . . Hours, . Minutes Western Area Power Administration - Upper Great Plains Region MRO North Dakota: Burleigh 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 75 0
2020 1 . . . . . Hours, . Minutes Entergy Corp SPP RE Arkansas: Texas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   68138
2020 1 . . . . . Hours, . Minutes Duke Energy Carolinas SERC North Carolina: South Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   66475
2020 1 . . . . . Hours, . Minutes Entergy - Transmission Operations Engineering SPP RE Arkansas: Cross 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 22 7541
2020 1 . . . . . 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
2020 1 . . . . . Hours, . Minutes Entergy - Transmission Operations Engineering SPP RE Arkansas: Yell 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
2020 2 . . . . . Hours, . Minutes Niagara Mohawk Power Corporation (dba National Grid) NPCC New York: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   7500
2020 2 . . . . . Hours, . Minutes Portland General Electric Co WECC Oregon: Clackamas 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
2020 2 . . . . . Hours, . Minutes Duke Energy Progress SERC North Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Distribution Interruption   284256
2020 2 . . . . . Hours, . Minutes Duke Energy Carolinas SERC North Carolina: South Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Transmission Interruption   89500
2020 2 . . . . . Hours, . 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   123359
2020 2 . . . . . Hours, . Minutes Exelon Corporation/PECO RF Pennsylvania: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather/Distribution Interruption   52000
2020 2 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC California: Alameda County, Contra Costa County, El Dorado County, Nevada County, Placer County, Sierra County, Santa Clara County, Napa County, Marin County, Santa Cruz County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 500 145000
2020 2 . . . . . Hours, . Minutes Dominion Energy VA SERC Virginia: North Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   87000
2020 2 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC Northern and Central California; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 91 70000
2020 3 . . . . . Hours, . Minutes FirstEnergy Corp RF Ohio: 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 19 11964
2020 3 . . . . . Hours, . Minutes Pacificorp WECC Utah: Loss of electric service to more than 50,000 customers for 1 hour or more.-Natural Disaster 237 73000
2020 3 . . . . . Hours, . Minutes ISO New England NPCC Connecticut: Massachusetts: Maine: New Hampshire: Rhode Island: Vermont: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   51026
2020 3 . . . . . Hours, . Minutes Entergy - Transmission Operations Engineering SERC Mississippi: Rankin 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 19 3136
2020 3 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC California: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 165 110800
2020 3 . . . . . Hours, . Minutes PECO Energy Co 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 40 15864
2020 3 . . . . . Hours, . Minutes Southern Company SERC Alabama: Georgia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 412 57744
2020 3 . . . . . Hours, . Minutes Somerset Operating Company NPCC Western NY Fuel supply emergencies that could impact electric power system adequacy or reliability.-Fuel Supply Deficiency 675  
2020 3 . . . . . Hours, . Minutes Entergy - Transmission Operations Engineering SERC Mississippi: Panola 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 4 1558
2020 4 . . . . . Hours, . Minutes Duke Energy Progress SERC North Carolina: South Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather    
2020 4 . . . . . Hours, . 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   68476
2020 4 . . . . . Hours, . Minutes Dominion Energy VA SERC North Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   95000
2020 4 . . . . . Hours, . Minutes Dominion Energy South Carolina SERC South Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   72233
2020 4 . . . . . Hours, . Minutes Tennessee Valley Authority SERC Tennessee: Hamilton County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   120000
2020 4 . . . . . Hours, . Minutes American Electric Power - (SPP Reliability Region) TRE Texas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   63289
2020 4 . . . . . Hours, . Minutes Duke Energy Carolinas SERC North Carolina: South Carolina: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   216400
2020 4 . . . . . Hours, . Minutes ISO New England NPCC Maine: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   340000
2020 4 . . . . . Hours, . Minutes Southern Company SERC Mississippi: Alabama: Georgia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 448 62828
2020 4 . . . . . 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   95000
2020 4 . . . . . Hours, . Minutes Ohio Edison Co WECC Ohio: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   82509
2020 4 . . . . . Hours, . Minutes American Electric Power - (RFC Reliability Region) RF Virginia: West Virginia: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   104000
2020 4 . . . . . Hours, . Minutes Duke Energy Midwest RF Indiana: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   93000
2020 4 . . . . . Hours, . Minutes Duke Energy Midwest RF Ohio: Kentucky: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   78314
2020 4 . . . . . Hours, . Minutes Arkansas Electric Coop Corp SPP RE Arkansas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   51000
2020 4 . . . . . Hours, . Minutes Bonneville Power Administration WECC Washington: 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
2020 4 . . . . . Hours, . 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   78007
2020 4 . . . . . Hours, . Minutes CenterPoint Energy Houston Electric, LLC TRE Texas: Harris County; Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   146660
2020 4 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC California: Stanislaus 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 7 6814
2020 4 . . . . . Hours, . Minutes Entergy Corp SERC Louisiana: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   77933
2020 4 . . . . . Hours, . Minutes Entergy - Transmission Operations Engineering TRE Texas: Jefferson 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 14 1
2020 4 . . . . . Hours, . Minutes Entergy Corp SPP RE Arkansas: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   95318
2020 4 . . . . . Hours, . Minutes Nebraska Public Power District MRO Nebraska: York 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 5  
2020 4 . . . . . Hours, . Minutes Florida Power & Light FRCC Florida: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   49999
2020 4 . . . . . Hours, . Minutes Pacific Gas & Electric Co WECC California: Placer County, Nevada 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 5 945
2020 4 . . . . . Hours, . Minutes Southern Company SERC Alabama: Georgia: Mississippi: Florida: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 375 52163
2020 4 . . . . . Hours, . Minutes Pacificorp WECC Wyoming: 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
2020 4 . . . . . Hours, . Minutes Entergy Corp SERC Mississippi: Arkansas: Louisiana: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather   55184
2020 4 . . . . . Hours, . Minutes Southern Company SERC Alabama: Mississippi: Georgia: Florida: Loss of electric service to more than 50,000 customers for 1 hour or more.-Severe Weather 552 77341

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