County annual report · FIPS 17087
2021 Johnson County, IL Power Outage Report
In 2021, customers in Johnson County, IL went without power for an average of 2.3 hours, a total of 15K customer-hours (Illinois average 2.3 hours). That ranks 60th worst of 102 Illinois counties and 2128th 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 Johnson 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 | June 2, 2021 00:00 | June 2, 2021 13:45 | 13h 45m | 1,271 | 1,137 |
| 2 | April 30, 2021 19:45 | April 30, 2021 20:45 | 1h | 1,110 | 278 |
| 3 | September 14, 2021 04:00 | September 14, 2021 04:15 | 15m | 489 | 122 |
| 4 | February 15, 2021 11:45 | February 15, 2021 16:30 | 4h 45m | 328 | 773 |
| 5 | September 26, 2021 13:45 | September 27, 2021 11:30 | 21h 45m | 322 | 7,004 |
| 6 | June 9, 2021 23:00 | June 10, 2021 12:00 | 13h | 293 | 666 |
| 7 | May 24, 2021 12:15 | May 24, 2021 12:30 | 15m | 203 | 51 |
| 8 | May 23, 2021 09:45 | May 23, 2021 12:00 | 2h 15m | 182 | 409 |
| 9 | July 28, 2021 13:00 | July 28, 2021 17:15 | 4h 15m | 162 | 665 |
| 10 | November 24, 2021 07:30 | November 24, 2021 12:15 | 4h 45m | 162 | 286 |
Outage episodes by size in 2021: 11 reached 100+ customers, 2 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 Johnson 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 |
| Southeastern IL Elec Coop, Inc | 2021 | 2.2 hrs | 1.32 | 2.0 hrs | 1.25 |
| Ameren | - | - | - | - | - |
| Egyptian Electric Coop Assn | - | - | - | - | - |
| Southern Illinois Elec 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 ÷ 6,500 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. Johnson County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Johnson 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/johnson-county