Mercer County Power Outage History
2014–2025 · New Jersey
Better than average — fewer or shorter outages than most counties. How grades are calculated
Outages by year
Outages by month (seasonality)
Worst outage events on record
| Date | Duration | Customers affected | Cause |
|---|---|---|---|
| Aug 4, 2020 | 106 hrs | 51,105 (26%) | Hurricane Isaias |
| May 17, 2021 | 3 hrs | 24,909 (13%) | Unnamed event |
| Mar 2, 2018 | 78 hrs | 24,128 (12%) | High Wind |
| Jun 28, 2016 | 2 hrs | 21,839 (11%) | Unnamed event |
| Jun 3, 2020 | 50 hrs | 20,421 (11%) | Thunderstorm Wind |
Over the 12 years from 2014 to 2025, Mercer County recorded 2,121 distinct power outage events, averaging 1.5 hours per event.
The single worst outage on record in Mercer County started August 4, 2020 (Hurricane Isaias), lasting 106 hours and leaving up to 51,105 customers without power (26% of the county) at its peak.
July has historically been the worst month for outages in Mercer County, with 260 events recorded during that month across the dataset.
Based on this history, Mercer County earns a Reliability Grade of B, placing it in the 62nd percentile nationally for grid reliability (higher percentile = more reliable).
Sized for Mercer County's outage profile
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Outage-prep kit
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Similar counties in New Jersey
Counties with the closest reliability grade and national percentile to Mercer County.
| County | Grade | National percentile |
|---|---|---|
| Essex County | B | 63rd |
| Union County | C | 60th |
| Bergen County | C | 59th |
| Atlantic County | B | 67th |
| Passaic County | C | 56th |
FAQ
How often does power go out in Mercer County?
Between 2014 and 2025, Mercer County recorded 2,121 outage events, averaging 1.5 hours each.
What is Mercer County's reliability grade?
Mercer County has a Reliability Grade of B, in the 62nd national percentile.
What was the worst power outage in Mercer County?
The worst outage on record started August 4, 2020 (Hurricane Isaias), lasting 106 hours and affecting up to 51,105 customers.