Power outage history
Stephenson County Illinois
7.2hours
without power for the average customer in a typical year, 2018–2025
16th most of 101 in Illinois close to the national median
Every day since 2015
Eleven years, one night at a time
Each cell is a day. The brighter it is, the larger the share of Stephenson's customers who were without power at that day's worst moment.
Year by year
Hours in the dark, per customer
2023 was the worst well-recorded year, at 20 hours for the average customer. Hatched years have a thin record and are left out of the averages.
Stephenson, hours without power per customer
The record
The biggest outages since 2015
Ranked by customer-hours lost: customers out multiplied by how long they stayed out. Times are local.
| Began | Storm | Peak out | Share | Lasted | 90% restored | Customer-hours |
|---|---|---|---|---|---|---|
| Feb 22, 2023 | Ice storm | 6,972 | 57% | 2.9 d | 30 h | 133k |
| Jul 15, 2024 | Thunderstorms | 6,053 | 49% | 2.7 d | 39 h | 95k |
| Jul 28, 2023 | Thunderstorms | 4,300 | 35% | 40 h | 26 h | 67k |
| May 21, 2024 | Thunderstorms | 4,426 | 36% | 29 h | 23 h | 67k |
| Jul 19, 2017 | Thunderstorms | 5,080 | 41% | 39 h | 25 h | 47k |
| Jan 10, 2020 | Winter storm | 2,781 | 23% | 47 h | 31 h | 46k |
| Aug 10, 2020 | Tornadoes | 2,595 | 21% | 25 h | 16 h | 30k |
| Dec 23, 2015 | No storm report | 3,846 | 31% | 8.0 h | 6.0 h | 24k |
| Jun 28, 2017 | Flooding | 4,868 | 40% | 18 h | 3.5 h | 23k |
| Mar 26, 2019 | No storm report | 4,937 | 40% | 5.5 h | 2.0 h | 14k |
| Jun 24, 2023 | Thunderstorms | 1,389 | 11% | 15 h | 14 h | 8.2k |
| Jul 13, 2018 | Thunderstorms | 471 | 4% | 19 h | – | 6.8k |
| Mar 31, 2023 | Tornadoes | 1,161 | 9% | 17 h | 15 h | 6.8k |
| Apr 4, 2016 | No storm report | 4,628 | 38% | 3.5 h | 1.5 h | 6.5k |
| May 17, 2017 | Thunderstorms | 701 | 6% | 22 h | 22 h | 5.8k |
| Aug 28, 2018 | No storm report | 628 | 5% | 14 h | 13 h | 5.8k |
| Jul 26, 2020 | No storm report | 1,052 | 9% | 6.8 h | 1.2 h | 4.9k |
| Feb 7, 2019 | Ice storm | 1,239 | 10% | 13 h | 12 h | 4.4k |
| Jun 14, 2016 | Thunderstorms | 1,440 | 12% | 9.5 h | 5.0 h | 4.4k |
| Aug 18, 2015 | No storm report | 3,957 | 32% | 2.2 h | 1.2 h | 4.2k |
| Aug 5, 2019 | No storm report | 1,327 | 11% | 4.5 h | 4.5 h | 4.0k |
| Jul 13, 2015 | No storm report | 957 | 8% | 6.0 h | 6.0 h | 3.8k |
| Jul 30, 2025 | No storm report | 1,808 | 15% | 5.5 h | 4.0 h | 3.7k |
| Mar 20, 2017 | No storm report | 1,266 | 10% | 5.0 h | 5.0 h | 3.7k |
| Aug 1, 2015 | No storm report | 473 | 4% | 28 h | – | 3.6k |
| Dec 15, 2021 | Thunderstorms | 883 | 7% | 16 h | 17 h | 3.6k |
| Jun 30, 2019 | Thunderstorms | 299 | 2% | 16 h | – | 3.5k |
| Jul 5, 2023 | No storm report | 661 | 5% | 5.5 h | 3.8 h | 3.5k |
| Aug 6, 2018 | Thunderstorms | 1,133 | 9% | 6.0 h | 6.0 h | 3.3k |
| Jun 23, 2017 | No storm report | 657 | 5% | 5.5 h | 3.5 h | 3.2k |
After the peak
How fast the lights come back
Each line is one major outage, from its peak. The amber line is the typical path.
When it happens
The outage clock
Customer-hours out by month (rings, January innermost) and local hour, 2018–2025.
What was happening
Weather behind the outages
Each outage is matched to NOAA storm reports for Stephenson from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.
- Thunderstorms 45%
- Ice storm 23%
- No storm on record 17%
- Winter storm 8.4%
- Tornadoes 6.1%
Who keeps the lights on
Utilities serving Stephenson
As each utility reports to the Energy Information Administration for its whole Illinois territory, not this county alone. Outage minutes include major storm days.
| Utility | Type | Outage min / yr | Excl. major storms | Outages / yr | Residential ¢/kWh | Customers |
|---|---|---|---|---|---|---|
| Commonwealth Edison Co | Investor Owned | 77 | 38 | 0.66 | 17.7 | 3.8M |
| Rock Energy Cooperative | Cooperative | 16 | 15 | 0.40 | 14.9 | 9.4k |
| Scenic Rivers Energy Coop | Cooperative | – | – | – | 15.1 | 12 |
EIA Form 861, latest year each utility reported. Outage minutes are SAIDI, the yearly minutes the average customer goes without power; outages a year are SAIFI.
Next door
Neighbouring counties
- Stephenson (this county) 7.2 h
- Carroll 5.9 h
- Jo Daviess 4.3 h
- Winnebago 4.0 h
- Ogle 3.2 h
- Green, WI 1.9 h
- Lafayette, WI 1.3 h
About these numbers
Notes
Outages come from the EAGLE-I record of utility outage maps collected every 15 minutes by Oak Ridge National Laboratory. Hours without power are customer-hours divided by the county's 12,248 electricity customers. Averages use well-covered years from 2018. Outages shorter than 15 minutes, and utilities that publish no outage map, are not in the record, so these figures understate the total. How every number is made →