County annual report · FIPS 30111
2022 Yellowstone County, MT Power Outage Report
In 2022, customers in Yellowstone County, MT went without power for an average of 2.1 hours, a total of 165K customer-hours (Montana average 3.5 hours). That ranks 37th worst of 50 Montana counties and 2246th of 2,976 nationally.
Compared with MT, the US and 2021
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Yellowstone County, 2022
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 25, 2022 01:00 | July 28, 2022 23:15 | 3d 22h | 7,375 | 53K |
| 2 | July 15, 2022 21:15 | July 16, 2022 05:15 | 8h | 2,078 | 3,457 |
| 3 | March 22, 2022 13:30 | March 22, 2022 16:30 | 3h | 1,985 | 2,482 |
| 4 | March 30, 2022 17:00 | March 30, 2022 20:30 | 3h 30m | 1,985 | 4,465 |
| 5 | August 26, 2022 15:00 | August 26, 2022 22:45 | 7h 45m | 1,868 | 2,838 |
| 6 | November 5, 2022 17:00 | November 6, 2022 07:45 | 14h 45m | 1,785 | 3,329 |
| 7 | October 17, 2022 16:15 | October 17, 2022 19:45 | 3h 30m | 1,746 | 2,184 |
| 8 | February 14, 2022 15:45 | February 14, 2022 21:00 | 5h 15m | 1,591 | 2,956 |
| 9 | August 6, 2022 13:45 | August 6, 2022 18:15 | 4h 30m | 1,585 | 5,100 |
| 10 | June 15, 2022 13:30 | June 16, 2022 04:00 | 14h 30m | 1,540 | 1,926 |
Outage episodes by size in 2022: 75 reached 100+ customers, 17 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 Yellowstone County reported on EIA Form 861 for 2022, 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 |
|---|---|---|---|---|---|
| NorthWestern Energy LLC - (MT) | 2022 | 2.2 hrs | 1.14 | 2.0 hrs | 1.09 |
| Mid-Yellowstone Elec Coop, Inc | 2018 | 4.5 hrs | 3.82 | 4.5 hrs | 3.82 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| NorthWestern Energy | - | - | - | - | - |
| Fergus Electric Coop, Inc | - | - | - | - | - |
| Yellowstone Valley Elec Co-op | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 76% of Montana's customers in 2022; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 77,606 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. Yellowstone County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Yellowstone County, MT annual power outage report, 2022, 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/2022/montana/yellowstone-county