– 0% of Delaware out 0 customers out in Pennsylvania

Power outage history

Delaware County Pennsylvania

6.6hours

without power for the average customer in a typical year, 2018–2025

32nd most of 67 in Pennsylvania close to the national median

Worst outage on record Mar 2, 2018 40% of customers out · 90% back in 3.1 days

Hours without power, average customer per year 6.6h / yr State average 6.0 h · national median 6.6 h

Major outages a year 0.9 Peaks over 10% of customers or 50,000 customers

Typical time to restore 90% 46hours Median across major outages, from the peak

Longest single outage 3.3days Mar 2, 2018, over 1% of customers out

Outage hours on storm days 90% Share falling on days with a NOAA storm report here

Worst year 2018 18 hours without power, average customer

Electricity customers 277,130 ORNL customer model · 8 well-covered years

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 Delaware's customers who were without power at that day's worst moment.

20152016201720182019202020212022202320242025

0%100% of customers out

Year by year

Hours in the dark, per customer

2018 was the worst well-recorded year, at 18 hours for the average customer. Hatched years have a thin record and are left out of the averages.

Delaware, hours without power per customer

DelawareUS median countyPennsylvania average

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
Mar 2, 2018	Winter storm	109,686	40%	3.3 d	3.1 d	4.1M
Jun 23, 2015	Thunderstorms	107,229	39%	3.3 d	2.2 d	3.0M
Jun 19, 2025	Thunderstorms	74,815	27%	3.2 d	2.6 d	1.8M
Jun 3, 2020	Thunderstorms	36,688	13%	3.0 d	2.2 d	914k
Feb 16, 2025	No storm report	49,986	18%	43 h	26 h	579k
Aug 4, 2020	Hurricane Isaias	29,451	11%	2.0 d	39 h	449k
Jan 9, 2024	Flooding	32,146	12%	41 h	30 h	415k
Mar 5, 2018	Winter storm	11,772	4%	2.0 d	20 h	336k
Jul 22, 2019	Thunderstorms	32,295	12%	22 h	20 h	247k
Aug 7, 2023	Thunderstorms	22,144	8%	24 h	32 h	222k
Oct 31, 2019	Thunderstorms	20,132	7%	24 h	35 h	212k
Dec 24, 2020	No storm report	14,769	5%	23 h	34 h	206k
Jul 2, 2019	Thunderstorms	13,498	5%	17 h	23 h	85k
Jun 8, 2016	Thunderstorms	19,684	7%	9.0 h	11 h	78k
Jul 18, 2016	Thunderstorms	18,657	7%	7.0 h	8.5 h	72k
Apr 4, 2025	Thunderstorms	11,458	4%	9.0 h	13 h	55k
Jul 25, 2016	No storm report	13,779	5%	6.0 h	5.2 h	54k
Apr 3, 2016	Thunderstorms	8,436	3%	10 h	9.5 h	46k
Jun 26, 2023	Thunderstorms	14,483	5%	6.5 h	13 h	41k
Jul 3, 2018	Heat	10,530	4%	6.5 h	4.2 h	34k
Jun 27, 2015	No storm report	9,724	4%	6.2 h	14 h	34k
Jun 23, 2025	Heat	5,410	2%	9.0 h	12 h	29k
Feb 25, 2016	No storm report	4,095	1%	9.5 h	–	27k
Feb 25, 2019	Windstorm	7,272	3%	4.2 h	5.8 h	26k
Jan 23, 2017	No storm report	5,026	2%	6.5 h	16 h	22k
Mar 7, 2022	Thunderstorms	5,769	2%	5.2 h	12 h	21k
Feb 13, 2017	Thunderstorms	6,249	2%	6.2 h	7.0 h	20k
Jun 23, 2024	Thunderstorms	5,812	2%	3.2 h	5.2 h	15k
Jun 6, 2015	No storm report	9,244	3%	2.0 h	1.8 h	15k
Apr 13, 2020	No storm report	5,037	2%	3.2 h	4.8 h	15k

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 Delaware from twelve hours before it began to its peak. Matching shows coincidence, not proof of cause.

Winter storm 44%
Thunderstorms 37%
No storm on record 9.8%
Tropical storm 4.7%
Flooding 4.4%
Heat 0.7%

Who keeps the lights on

Utilities serving Delaware

As each utility reports to the Energy Information Administration for its whole Pennsylvania territory, not this county alone. Outage minutes include major storm days.

Utility	Type	Outage min / yr	Excl. major storms	Outages / yr	Residential ¢/kWh	Customers
PECO Energy Co	Investor Owned	328	59	1.12	18.0	1.5M

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

Montgomery 13 h
Chester 9.3 h
Delaware (this county) 6.6 h
New Castle, DE 4.0 h
Gloucester, NJ 2.4 h
Philadelphia 1.8 h

Across Pennsylvania

Where it is darkest

Hours / yr64+

All Pennsylvania counties →

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 277,130 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 →