County annual report · FIPS 30091
2025 Sheridan County, MT Power Outage Report
In 2025, customers in Sheridan County, MT went without power for an average of 0.3 hours, a total of 503 customer-hours (Montana average 6.8 hours). That ranks 45th worst of 51 Montana counties and 2906th of 3,000 nationally.
Compared with MT, the US and 2024
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Sheridan 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 | November 25, 2025 05:15 | November 25, 2025 06:00 | 45m | 94 | 71 |
| 2 | August 3, 2025 04:15 | August 3, 2025 04:45 | 30m | 92 | 42 |
| 3 | April 28, 2025 08:45 | April 28, 2025 11:00 | 2h 15m | 64 | 124 |
| 4 | August 26, 2025 04:15 | August 26, 2025 05:15 | 1h | 30 | 29 |
| 5 | May 7, 2025 20:45 | May 8, 2025 00:45 | 4h | 22 | 88 |
| 6 | August 3, 2025 03:15 | August 3, 2025 03:30 | 15m | 11 | 3 |
| 7 | May 12, 2025 19:45 | May 12, 2025 21:15 | 1h 30m | 9 | 14 |
| 8 | July 12, 2025 16:45 | July 12, 2025 17:45 | 1h | 9 | 8 |
| 9 | April 25, 2025 15:45 | April 25, 2025 20:30 | 4h 45m | 8 | 38 |
| 10 | May 6, 2025 13:45 | May 6, 2025 19:45 | 6h | 7 | 42 |
Outage episodes by size in 2025: 0 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 Sheridan 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 |
|---|---|---|---|---|---|
| Montana-Dakota Utilities Co | 2024 | 2.9 hrs | 1.26 | 2.1 hrs | 1.10 |
| Sheridan Electric Coop, Inc | - | - | - | - | - |
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 Montana's customers in 2025; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 1,766 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. Sheridan County has data for 2017–2025.
Cite this report
MassOutage (massoutage.com), Sheridan County, MT 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/montana/sheridan-county