County annual report · FIPS 55105
2021 Rock County, WI Power Outage Report
In 2021, customers in Rock County, WI went without power for an average of 1.6 hours, a total of 88K customer-hours (Wisconsin average 4.7 hours). That ranks 55th worst of 72 Wisconsin counties and 2435th of 2,974 nationally.
Compared with WI, the US and 2020
Coverage line is EAGLE-I's share of Wisconsin customers tracked each year.
Biggest outages in Rock 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 | June 18, 2021 07:45 | June 18, 2021 17:45 | 10h | 3,101 | 4,300 |
| 2 | July 17, 2021 22:30 | July 18, 2021 06:45 | 8h 15m | 2,144 | 6,724 |
| 3 | July 15, 2021 05:30 | July 15, 2021 23:45 | 18h 15m | 1,682 | 4,958 |
| 4 | May 1, 2021 11:45 | May 1, 2021 13:30 | 1h 45m | 1,639 | 1,640 |
| 5 | August 10, 2021 23:15 | August 12, 2021 09:15 | 1d 10h | 1,637 | 7,370 |
| 6 | September 4, 2021 08:30 | September 4, 2021 10:30 | 2h | 1,634 | 3,268 |
| 7 | December 15, 2021 15:00 | December 17, 2021 02:30 | 1d 11h | 1,563 | 6,674 |
| 8 | September 22, 2021 18:30 | September 22, 2021 20:00 | 1h 30m | 1,471 | 1,568 |
| 9 | August 24, 2021 23:00 | August 25, 2021 06:30 | 7h 30m | 1,381 | 1,756 |
| 10 | May 1, 2021 15:30 | May 1, 2021 16:30 | 1h | 1,344 | 966 |
Outage episodes by size in 2021: 67 reached 100+ customers, 16 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 Rock 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 |
|---|---|---|---|---|---|
| Wisconsin Electric Power Co | 2021 | 7.0 hrs | 1.13 | 1.7 hrs | 0.73 |
| Rock Energy Cooperative | 2021 | 43 min | 0.47 | - | - |
| City of Stoughton - (WI) | 2021 | 36 min | 0.41 | 36 min | 0.41 |
| Alliant Energy (Interstate Power & Light) | - | - | - | - | - |
| Wisconsin Power & Light Co | - | - | - | - | - |
| Brodhead Water & Lighting Comm | - | - | - | - | - |
| City of Evansville | - | - | - | - | - |
About this data
- Outage figures come from DOE/ORNL EAGLE-I, which records customers out by county every 15 minutes. EAGLE-I tracked about 85% of Wisconsin's customers in 2021; utilities it does not see are not counted.
- Hours per customer = outage customer-minutes ÷ 56,401 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. Rock County has data for 2015–2025.
Cite this report
MassOutage (massoutage.com), Rock County, WI 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/wisconsin/rock-county