County annual report · FIPS 30003
2020 Big Horn County, MT Power Outage Report
In 2020, customers in Big Horn County, MT went without power for an average of 0.3 hours, a total of 2,114 customer-hours (Montana average 5.6 hours). That ranks 46th worst of 50 Montana counties and 2873rd of 3,019 nationally.
Compared with MT, the US and 2019
Coverage line is EAGLE-I's share of Montana customers tracked each year.
Biggest outages in Big Horn County, 2020
The 10 outage episodes with the most customers out at once. Times are UTC.
| # | Started (UTC) | Ended (UTC) | Duration | Peak out | Customer-hours |
|---|---|---|---|---|---|
| 1 | December 17, 2020 17:15 | December 17, 2020 18:00 | 45m | 82 | 62 |
| 2 | June 6, 2020 07:00 | June 6, 2020 11:30 | 4h 30m | 58 | 145 |
| 3 | October 26, 2020 02:15 | October 26, 2020 08:00 | 5h 45m | 42 | 184 |
| 4 | July 20, 2020 13:00 | July 21, 2020 00:15 | 11h 15m | 32 | 270 |
| 5 | July 8, 2020 01:15 | July 8, 2020 11:00 | 9h 45m | 31 | 139 |
| 6 | October 9, 2020 17:00 | October 9, 2020 20:30 | 3h 30m | 24 | 84 |
| 7 | August 9, 2020 14:00 | August 9, 2020 17:45 | 3h 45m | 23 | 50 |
| 8 | October 17, 2020 14:00 | October 17, 2020 16:15 | 2h 15m | 22 | 50 |
| 9 | March 23, 2020 20:45 | March 23, 2020 21:45 | 1h | 21 | 11 |
| 10 | April 9, 2020 15:15 | April 9, 2020 20:15 | 5h | 20 | 10 |
Outage episodes by size in 2020: 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 Big Horn County reported on EIA Form 861 for 2020, 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) | 2020 | 2.8 hrs | 1.13 | 2.0 hrs | 1.02 |
| Powder River Energy Corp | 2020 | 4.8 hrs | 2.30 | 3.2 hrs | 1.94 |
| Big Horn Rural Electric Co | 2018 | 4.0 hrs | 1.80 | - | - |
| Mid-Yellowstone Elec Coop, Inc | 2018 | 4.5 hrs | 3.82 | 4.5 hrs | 3.82 |
| WAPA-- Western Area Power Administration | - | - | - | - | - |
| Tongue River Electric Coop Inc | - | - | - | - | - |
| Yellowstone Valley Elec Co-op | - | - | - | - | - |
| Big Horn County Elec 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 76% of Montana's customers in 2020; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 6,865 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. Big Horn County has data for 2019–2025.
Cite this report
MassOutage (massoutage.com), Big Horn County, MT annual power outage report, 2020, 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/2020/montana/big-horn-county