County annual report · FIPS 17125
2025 Mason County, IL Power Outage Report
In 2025, customers in Mason County, IL went without power for an average of 3.8 hours, a total of 19K customer-hours (Illinois average 2.5 hours). That ranks 49th worst of 102 Illinois counties and 1807th of 3,000 nationally.
Compared with IL, the US and 2024
Coverage line is EAGLE-I's share of Illinois customers tracked each year.
Biggest outages in Mason County, 2025
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 19, 2025 14:15 | July 19, 2025 18:30 | 4h 15m | 934 | 2,804 |
| 2 | May 18, 2025 06:45 | May 18, 2025 12:00 | 5h 15m | 793 | 1,184 |
| 3 | July 12, 2025 03:00 | July 12, 2025 10:30 | 7h 30m | 337 | 1,221 |
| 4 | June 18, 2025 16:15 | June 18, 2025 22:15 | 6h | 331 | 608 |
| 5 | November 26, 2025 16:00 | November 26, 2025 19:00 | 3h | 326 | 494 |
| 6 | May 20, 2025 06:15 | May 20, 2025 11:45 | 5h 30m | 323 | 593 |
| 7 | July 25, 2025 12:30 | July 25, 2025 13:45 | 1h 15m | 316 | 254 |
| 8 | June 27, 2025 03:30 | June 28, 2025 02:45 | 23h 15m | 312 | 6,040 |
| 9 | July 18, 2025 07:15 | July 18, 2025 09:45 | 2h 30m | 306 | 689 |
| 10 | June 25, 2025 00:45 | June 25, 2025 03:15 | 2h 30m | 300 | 734 |
Outage episodes by size in 2025: 13 reached 100+ customers, 0 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 Mason County reported on EIA Form 861 for 2025, 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 | 2024 | 3.7 hrs | 1.13 | 2.0 hrs | 0.91 |
| Menard Electric Coop | 2024 | 2.8 hrs | 1.49 | 1.9 hrs | 1.27 |
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 2025; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 4,847 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. Mason County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Mason County, IL annual power outage report, 2025, 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/2025/illinois/mason-county