County annual report · FIPS 17017
2021 Cass County, IL Power Outage Report
In 2021, customers in Cass County, IL went without power for an average of 1.3 hours, a total of 7,900 customer-hours (Illinois average 2.3 hours). That ranks 88th worst of 102 Illinois counties and 2550th of 2,974 nationally.
Compared with IL, the US and 2020
Coverage line is EAGLE-I's share of Illinois customers tracked each year.
Biggest outages in Cass County, 2021
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | July 10, 2021 19:45 | July 10, 2021 22:45 | 3h | 1,237 | 1,515 |
| 2 | December 16, 2021 05:15 | December 16, 2021 06:30 | 1h 15m | 756 | 764 |
| 3 | December 2, 2021 10:30 | December 2, 2021 11:00 | 30m | 694 | 347 |
| 4 | June 19, 2021 08:15 | June 19, 2021 11:00 | 2h 45m | 453 | 1,020 |
| 5 | September 2, 2021 05:00 | September 2, 2021 07:30 | 2h 30m | 334 | 834 |
| 6 | March 31, 2021 21:00 | March 31, 2021 22:15 | 1h 15m | 249 | 249 |
| 7 | December 11, 2021 02:00 | December 13, 2021 01:15 | 1d 23h | 86 | 1,193 |
| 8 | August 23, 2021 19:00 | August 24, 2021 19:45 | 1d | 30 | 494 |
| 9 | May 4, 2021 07:45 | May 4, 2021 14:30 | 6h 45m | 25 | 169 |
| 10 | September 6, 2021 11:15 | September 6, 2021 18:45 | 7h 30m | 21 | 146 |
Outage episodes by size in 2021: 6 reached 100+ customers, 1 reached 1,000+ customers, 0 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 Cass County reported on EIA Form 861 for 2021, 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 |
|---|---|---|---|---|---|
| Ameren Illinois Company | 2021 | 3.2 hrs | 1.11 | 2.0 hrs | 0.88 |
| Menard Electric Coop | 2021 | 7.8 hrs | 2.83 | 2.8 hrs | 1.73 |
| Ameren | - | - | - | - | - |
| Illinois Rural Electric Coop | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 98% of Illinois's customers in 2021; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 6,087 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. Cass County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Cass County, IL annual power outage report, 2021, 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/2021/illinois/cass-county