County annual report · FIPS 30077
2021 Powell County, MT Power Outage Report
In 2021, customers in Powell County, MT went without power for an average of 1.5 hours, a total of 6,769 customer-hours (Montana average 5.0 hours). That ranks 44th worst of 51 Montana counties and 2467th of 2,974 nationally.
Compared with MT, the US and 2020
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Powell 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 | February 13, 2021 07:30 | February 13, 2021 10:00 | 2h 30m | 656 | 1,598 |
| 2 | August 27, 2021 09:15 | August 27, 2021 11:45 | 2h 30m | 433 | 1,083 |
| 3 | August 13, 2021 15:00 | August 13, 2021 18:30 | 3h 30m | 179 | 242 |
| 4 | March 29, 2021 08:30 | March 30, 2021 20:45 | 1d 12h | 162 | 869 |
| 5 | January 10, 2021 17:45 | January 10, 2021 18:45 | 1h | 142 | 142 |
| 6 | January 13, 2021 16:45 | January 13, 2021 18:45 | 2h | 126 | 199 |
| 7 | May 7, 2021 22:45 | May 8, 2021 03:45 | 5h | 118 | 236 |
| 8 | January 10, 2021 14:45 | January 10, 2021 16:00 | 1h 15m | 116 | 116 |
| 9 | August 3, 2021 14:30 | August 3, 2021 15:15 | 45m | 81 | 41 |
| 10 | August 11, 2021 14:30 | August 11, 2021 16:00 | 1h 30m | 79 | 119 |
Outage episodes by size in 2021: 8 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 Powell 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 |
|---|---|---|---|---|---|
| NorthWestern Energy LLC - (MT) | 2021 | 2.5 hrs | 1.37 | 2.1 hrs | 1.18 |
| Missoula Electric Coop, Inc | 2021 | 12.7 hrs | 3.21 | 6.5 hrs | 2.76 |
| Bonneville Power Administration | - | - | - | - | - |
| NorthWestern Energy | - | - | - | - | - |
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 2021; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 4,506 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. Powell County has data for 2020–2025.
Cite this report
MassOutage (massoutage.com), Powell County, MT 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/montana/powell-county