County annual report · FIPS 17031
2020 Cook County, IL Power Outage Report
In 2020, customers in Cook County, IL went without power for an average of 5.6 hours, a total of 12.1M customer-hours (Illinois average 5.9 hours). That ranks 32nd worst of 102 Illinois counties and 1305th of 3,019 nationally.
Compared with IL, the US and 2019
Coverage line is EAGLE-I's share of Illinois customers tracked each year.
Biggest outages in Cook County, 2020
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | August 5, 2020 10:30 | September 14, 2020 05:15 | 39d 18h | 279,858 | 10.2M |
| 2 | June 8, 2020 04:45 | July 12, 2020 09:45 | 34d 5h | 31,346 | 644K |
| 3 | July 13, 2020 07:30 | July 26, 2020 08:00 | 13d | 15,705 | 151K |
| 4 | November 10, 2020 12:30 | November 12, 2020 10:15 | 1d 21h | 8,982 | 49K |
| 5 | November 12, 2020 11:15 | November 27, 2020 03:00 | 14d 15h | 6,698 | 61K |
| 6 | May 16, 2020 13:15 | May 21, 2020 09:30 | 4d 20h | 5,986 | 30K |
| 7 | October 9, 2020 12:00 | October 25, 2020 04:30 | 15d 16h | 5,922 | 98K |
| 8 | May 13, 2020 12:00 | May 16, 2020 09:45 | 2d 21h | 5,634 | 39K |
| 9 | July 26, 2020 11:45 | July 28, 2020 09:45 | 1d 22h | 4,760 | 24K |
| 10 | July 28, 2020 10:45 | August 5, 2020 09:45 | 7d 23h | 4,193 | 41K |
Outage episodes by size in 2020: 146 reached 100+ customers, 69 reached 1,000+ customers, 3 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 2020, 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 | 2020 | 5.7 hrs | 0.83 | 40 min | 0.55 |
| Northern Indiana Pub Serv Co | 2020 | 7.9 hrs | 1.26 | 2.3 hrs | 0.90 |
| 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 94% of Illinois's customers in 2020; 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, 2020, 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/2020/illinois/cook-county