County annual report · FIPS 17031
2023 Cook County, IL Power Outage Report
In 2023, customers in Cook County, IL went without power for an average of 1.0 hours, a total of 2.2M customer-hours (Illinois average 4.0 hours). That ranks 95th worst of 102 Illinois counties and 2667th of 2,977 nationally.
Compared with IL, the US and 2022
Coverage line is EAGLE-I's share of Illinois customers tracked each year.
Biggest outages in Cook County, 2023
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | February 22, 2023 13:45 | February 27, 2023 04:30 | 4d 14h | 23,437 | 356K |
| 2 | July 17, 2023 11:45 | August 10, 2023 10:30 | 23d 22h | 21,521 | 268K |
| 3 | July 10, 2023 09:45 | July 17, 2023 07:45 | 6d 22h | 18,010 | 209K |
| 4 | March 30, 2023 08:45 | April 3, 2023 02:15 | 3d 17h | 17,746 | 83K |
| 5 | September 11, 2023 08:15 | September 17, 2023 19:15 | 6d 11h | 17,324 | 49K |
| 6 | June 29, 2023 10:15 | July 7, 2023 10:15 | 8d | 10,194 | 138K |
| 7 | April 3, 2023 04:45 | April 9, 2023 08:15 | 6d 3h | 7,634 | 64K |
| 8 | June 13, 2023 11:15 | June 27, 2023 08:00 | 13d 20h | 7,013 | 136K |
| 9 | May 31, 2023 09:30 | June 4, 2023 08:00 | 3d 22h | 4,639 | 19K |
| 10 | August 23, 2023 09:30 | August 26, 2023 05:00 | 2d 19h | 3,661 | 56K |
Outage episodes by size in 2023: 177 reached 100+ customers, 69 reached 1,000+ customers, 6 reached 10,000+ customers.
Utility reliability filed with the EIA
SAIDI (average outage time per customer) and SAIFI (average interruptions per customer) that utilities serving Cook County reported on EIA Form 861 for 2023, or their most recent earlier filing. Utility-wide figures, not county-specific.
| Utility | EIA year | SAIDI | SAIFI | SAIDI excl. major events | SAIFI excl. major events |
|---|---|---|---|---|---|
| Commonwealth Edison Co | 2023 | 1.6 hrs | 0.61 | 35 min | 0.48 |
| Northern Indiana Pub Serv Co | 2023 | 5.3 hrs | 1.14 | 2.5 hrs | 0.87 |
| University of Illinois | - | - | - | - | - |
| Village of Winnetka - (IL) | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about n/a of Illinois's customers in 2023; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 2,162,007 customers (ORNL modeled county customer count), including major storm days. It is comparable across counties but is not the SAIDI a utility files.
- An outage event is a continuous stretch with customers out; counts at 100, 1,000 and 10,000+ use its peak.
- Years loaded: 2015–2025. Cook County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Cook County, IL annual power outage report, 2023, data as of Oct 3, 2026 02:41 UTC, sources: DOE EAGLE-I (https://eagle-i.doe.gov/); EAGLE-I modeled customer counts (MCC) (https://figshare.com/); EIA Form 861 (utility reliability) (https://www.eia.gov/electricity/data/eia861/). https://massoutage.com/reports/2023/illinois/cook-county