County annual report · FIPS 17111
2023 McHenry County, IL Power Outage Report
In 2023, customers in McHenry County, IL went without power for an average of 7.9 hours, a total of 951K customer-hours (Illinois average 4.0 hours). That ranks 37th worst of 102 Illinois counties and 1037th 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 McHenry 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 18:00 | February 26, 2023 06:15 | 3d 12h | 36,109 | 849K |
| 2 | October 17, 2023 01:30 | October 17, 2023 08:00 | 6h 30m | 5,905 | 4,150 |
| 3 | June 14, 2023 00:30 | June 14, 2023 06:30 | 6h | 3,180 | 3,155 |
| 4 | April 5, 2023 08:30 | April 6, 2023 04:00 | 19h 30m | 3,101 | 2,884 |
| 5 | July 26, 2023 14:15 | July 27, 2023 06:15 | 16h | 1,571 | 5,749 |
| 6 | November 21, 2023 16:15 | November 21, 2023 21:00 | 4h 45m | 1,484 | 548 |
| 7 | July 12, 2023 15:15 | July 13, 2023 07:45 | 16h 30m | 1,456 | 2,645 |
| 8 | May 31, 2023 13:15 | June 1, 2023 05:00 | 15h 45m | 1,073 | 1,496 |
| 9 | April 20, 2023 21:15 | April 21, 2023 04:45 | 7h 30m | 1,023 | 1,928 |
| 10 | August 17, 2023 10:30 | August 17, 2023 18:00 | 7h 30m | 1,020 | 580 |
Outage episodes by size in 2023: 121 reached 100+ customers, 10 reached 1,000+ customers, 1 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 McHenry 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 |
| Rock Energy Cooperative | 2023 | 40 min | 0.38 | 22 min | 0.22 |
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 ÷ 120,381 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. McHenry County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), McHenry 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/mchenry-county