Quick answer: in 2024 the average U.S. home lost power for about 10 hours, nearly double the year before, according to U.S. Energy Information Administration (EIA) data. South Carolina was worst at 52.3 hours, almost all of it from major storms. Over 2022–2024, Maine averaged the most, at 25.4 hours a year. In 28 of the 51 (50 states plus D.C.), a 1 kWh power station covers a bad recent year for a fridge, Wi-Fi and a few lights. In the storm states, plan for 2–3 kWh or more.
How we built this: we took the official SAIDI figures (average minutes without power per customer) from the EIA’s Electric Power Annual, Table 11.4, “any method” columns for 2022–2024, converted them to hours and calculated battery sizes with the formula shown below. These are averages across all customers, not measurements of any single outage, and we don’t lab-test power stations. See How We Research.
Key findings
- 2024 was a bad year everywhere storms hit. The average U.S. customer was without power for 10.2 hours in 2024, up from 5.6 hours in 2022 and 5.7 hours in 2023. EIA’s own headline figure is 11 hours because it uses a slightly different method (utilities that follow the IEEE standard).
- South Carolina: 52.3 hours. About 96% of that time fell on major-event days, the year Hurricane Helene hit. Without major storms, South Carolina homes lost only about 2 hours.
- Maine has the worst three-year record. It averaged 25.4 hours a year over 2022–2024, more than Florida (14.6) or Texas (11.0).
- West Virginia has the worst everyday grid. Even without major storms, its homes lost 8.1 hours in 2024, nearly four times the national 2.1 hours.
- Nine states topped 12 hours in 2024: South Carolina, Maine, North Carolina, Florida, Texas, Georgia, West Virginia, New Hampshire and Louisiana.
- The steadiest power: Washington, D.C. (0.5 hours), South Dakota (1.4) and Arizona (1.5) in 2024.
The 10 states with the most hours without power (2024)
| Rank | State | 2024 (hours) | 2022–2024 average (hours a year) | Without major storms, 2024 (hours) | Battery to plan for |
|---|---|---|---|---|---|
| 1 | South Carolina | 52.3 | 20.0 | 2.0 | 3 kWh+ plus expansion or solar |
| 2 | Maine | 29.1 | 25.4 | 4.6 | 3 kWh+ plus expansion or solar |
| 3 | North Carolina | 24.0 | 11.9 | 2.4 | Extra-large (~3 kWh) |
| 4 | Florida | 22.0 | 14.6 | 1.1 | Extra-large (~3 kWh) |
| 5 | Texas | 21.2 | 11.0 | 2.2 | Extra-large (~3 kWh) |
| 6 | Georgia | 20.5 | 10.2 | 3.5 | Extra-large (~3 kWh) |
| 7 | West Virginia | 19.4 | 16.2 | 8.1 | Extra-large (~3 kWh) |
| 8 | New Hampshire | 15.4 | 12.1 | 2.2 | Large (~2 kWh) |
| 9 | Louisiana | 12.1 | 9.0 | 3.4 | Large (~2 kWh) |
| 10 | Vermont | 11.6 | 13.4 | 4.6 | Large (~2 kWh) |
How much battery does your state need?
We sized each state for its worst year out of the last three, not the average one. A backup plan should cover a bad year. The load is a typical “keep the house running” set: an average refrigerator (about 62.5 W over a day), a Wi-Fi router and modem (about 15 W) and a few LED lights and phone chargers, for about 95 W in total.
Battery size (Wh) = hours to cover × (95 W + 10 W) ÷ 0.85
- Step 1: Find your state’s worst recent year in the table below (the “worst of 3 years” column).
- Step 2: Add 10 W to your load for the inverter, the part that turns battery power into wall power.
- Step 3: Divide by 0.85, because only about 85% of a battery’s rated capacity is usable in practice.
Example: South Carolina’s worst recent year was 52.3 hours. 52.3 × 105 ÷ 0.85 = about 6,460 Wh. That is more than any single mid-size unit holds, so the realistic plan is a 3 kWh-class unit plus an expansion battery or solar panels.
| Power station size | Hours of fridge + Wi-Fi + lights (about 95 W) | States where it covers a bad recent year |
|---|---|---|
| Small (288 Wh) | about 2.3 hours | 5 |
| Mid-size (1,024 Wh) | about 8.3 hours | 23 more (28 in total) |
| Large (2,048 Wh) | about 16.6 hours | 15 more (43 in total) |
| Extra-large (3,072 Wh) | about 24.9 hours | 6 more (49 in total) |
| 3 kWh+ with expansion or solar | more than 25 hours | 2 (Maine and South Carolina) |
All 50 states and D.C.
| State | 2024 (hours) | 2022–2024 average | Without major storms, 2024 | Worst of 3 years | Battery for ~95 W (Wh) | Size class |
|---|---|---|---|---|---|---|
| Alabama | 4.7 | 4.4 | 2.0 | 4.9 | 610 | Mid-size (~1 kWh) |
| Alaska | 5.5 | 7.1 | 3.2 | 9.6 | 1,180 | Large (~2 kWh) |
| Arizona | 1.5 | 1.9 | 1.2 | 2.3 | 290 | Small (~300 Wh) |
| Arkansas | 8.5 | 10.2 | 3.2 | 15.2 | 1,880 | Large (~2 kWh) |
| California | 4.7 | 4.6 | 2.6 | 5.8 | 710 | Mid-size (~1 kWh) |
| Colorado | 4.3 | 2.8 | 2.0 | 4.3 | 530 | Mid-size (~1 kWh) |
| Connecticut | 2.6 | 2.6 | 1.2 | 2.7 | 340 | Mid-size (~1 kWh) |
| Delaware | 1.9 | 1.7 | 1.1 | 1.9 | 240 | Small (~300 Wh) |
| District of Columbia | 0.5 | 0.8 | 0.4 | 1.2 | 150 | Small (~300 Wh) |
| Florida | 22.0 | 14.6 | 1.1 | 22.0 | 2,720 | Extra-large (~3 kWh) |
| Georgia | 20.5 | 10.2 | 3.5 | 20.5 | 2,530 | Extra-large (~3 kWh) |
| Hawaii | 5.3 | 5.6 | 3.8 | 8.2 | 1,010 | Mid-size (~1 kWh) |
| Idaho | 3.9 | 3.1 | 2.9 | 3.9 | 480 | Mid-size (~1 kWh) |
| Illinois | 2.6 | 2.5 | 1.0 | 3.5 | 430 | Mid-size (~1 kWh) |
| Indiana | 5.2 | 5.8 | 2.0 | 7.6 | 940 | Mid-size (~1 kWh) |
| Iowa | 2.8 | 2.0 | 1.5 | 2.8 | 340 | Mid-size (~1 kWh) |
| Kansas | 4.8 | 4.2 | 1.7 | 4.8 | 590 | Mid-size (~1 kWh) |
| Kentucky | 10.8 | 10.3 | 2.6 | 14.5 | 1,790 | Large (~2 kWh) |
| Louisiana | 12.1 | 9.0 | 3.4 | 12.1 | 1,500 | Large (~2 kWh) |
| Maine | 29.1 | 25.4 | 4.6 | 31.1 | 3,840 | 3 kWh+ plus expansion or solar |
| Maryland | 2.0 | 3.0 | 1.3 | 4.3 | 530 | Mid-size (~1 kWh) |
| Massachusetts | 1.7 | 2.9 | 1.3 | 4.3 | 530 | Mid-size (~1 kWh) |
| Michigan | 7.8 | 11.5 | 2.7 | 18.2 | 2,250 | Extra-large (~3 kWh) |
| Minnesota | 3.7 | 3.4 | 1.5 | 4.6 | 560 | Mid-size (~1 kWh) |
| Mississippi | 9.5 | 10.1 | 4.4 | 13.4 | 1,650 | Large (~2 kWh) |
| Missouri | 3.7 | 4.1 | 1.8 | 6.2 | 770 | Mid-size (~1 kWh) |
| Montana | 5.9 | 3.9 | 2.6 | 5.9 | 720 | Mid-size (~1 kWh) |
| Nebraska | 10.7 | 4.4 | 1.2 | 10.7 | 1,320 | Large (~2 kWh) |
| Nevada | 2.6 | 2.7 | 1.1 | 3.3 | 400 | Mid-size (~1 kWh) |
| New Hampshire | 15.4 | 12.1 | 2.2 | 15.4 | 1,900 | Large (~2 kWh) |
| New Jersey | 2.9 | 2.1 | 1.7 | 2.9 | 360 | Mid-size (~1 kWh) |
| New Mexico | 4.6 | 3.5 | 2.6 | 4.6 | 570 | Mid-size (~1 kWh) |
| New York | 3.7 | 3.0 | 1.2 | 3.7 | 450 | Mid-size (~1 kWh) |
| North Carolina | 24.0 | 11.9 | 2.4 | 24.0 | 2,970 | Extra-large (~3 kWh) |
| North Dakota | 1.7 | 4.8 | 1.4 | 9.3 | 1,150 | Large (~2 kWh) |
| Ohio | 8.5 | 7.2 | 2.2 | 8.5 | 1,050 | Large (~2 kWh) |
| Oklahoma | 4.5 | 7.6 | 2.0 | 14.9 | 1,850 | Large (~2 kWh) |
| Oregon | 9.8 | 5.8 | 2.2 | 9.8 | 1,220 | Large (~2 kWh) |
| Pennsylvania | 5.6 | 4.4 | 2.2 | 5.6 | 690 | Mid-size (~1 kWh) |
| Rhode Island | 1.7 | 1.6 | 1.0 | 1.7 | 220 | Small (~300 Wh) |
| South Carolina | 52.3 | 20.0 | 2.0 | 52.3 | 6,460 | 3 kWh+ plus expansion or solar |
| South Dakota | 1.4 | 2.7 | 1.0 | 5.5 | 670 | Mid-size (~1 kWh) |
| Tennessee | 4.6 | 8.6 | 2.7 | 14.3 | 1,770 | Large (~2 kWh) |
| Texas | 21.2 | 11.0 | 2.2 | 21.2 | 2,620 | Extra-large (~3 kWh) |
| Utah | 2.0 | 2.0 | 1.8 | 2.1 | 260 | Small (~300 Wh) |
| Vermont | 11.6 | 13.4 | 4.6 | 16.1 | 1,980 | Large (~2 kWh) |
| Virginia | 7.0 | 6.9 | 2.8 | 9.9 | 1,220 | Large (~2 kWh) |
| Washington | 10.4 | 6.5 | 2.6 | 10.4 | 1,280 | Large (~2 kWh) |
| West Virginia | 19.4 | 16.2 | 8.1 | 19.4 | 2,400 | Extra-large (~3 kWh) |
| Wisconsin | 4.4 | 4.0 | 1.5 | 4.6 | 560 | Mid-size (~1 kWh) |
| Wyoming | 2.3 | 2.4 | 1.8 | 2.8 | 350 | Mid-size (~1 kWh) |
What the averages hide
SAIDI spreads every lost minute across every customer in the state, including the many homes that never lost power. So if a storm knocks out a quarter of a state for two days, the state average might show about 12 hours, while the homes that were hit went dark for 48. In July 2024, Hurricane Beryl alone left 2.6 million Texas customers without power, according to the EIA.
That is why the state number is a floor, not a ceiling. If you live where hurricanes, ice storms or wildfire shutoffs happen, plan for days. One full day of fridge, Wi-Fi and lights takes about 3 kWh (24 × 105 ÷ 0.85 = about 2,960 Wh), so a multi-day plan usually means a large battery plus solar panels to recharge it. Our hurricane power outage checklist covers the rest of the prep.
Three households, three plans
An apartment in Arizona
Example: Arizona’s worst recent year was 2.3 hours. 2.3 × 105 ÷ 0.85 = about 290 Wh, so a small 288 Wh power station just covers the fridge, Wi-Fi and lights for a bad year. If you only need Wi-Fi, phones and a lamp, the same unit lasts far longer.
A family in Maine
Example: Maine’s worst recent year was 31.1 hours. 31.1 × 105 ÷ 0.85 = about 3,840 Wh, more than a 3 kWh unit holds. Add an expansion battery, or pair a 2–3 kWh unit with solar panels. In winter the bigger question is heat: a gas furnace still needs power for its blower, so read can a power station run a gas furnace before you size.
A CPAP user in West Virginia
Example: a CPAP with the humidifier off uses about 30 W, or (30 + 10) × 8 = 320 Wh for an 8-hour night. A 1,024 Wh unit gives 1,024 × 0.85 ÷ 320 = about 2.7 nights. Covering the fridge and Wi-Fi as well for West Virginia’s 19.4-hour planning figure adds about 2,400 Wh, so the total is about 2,770 Wh: a 3 kWh-class unit. See how many nights a power station runs a CPAP for humidifier settings.
Common mistakes when sizing for outages
- Sizing for an average year. Outages come in bad years. Use the worst of the last three, as we do here.
- Trusting the number on the box. Plan on about 85% of the rated Wh, plus the inverter’s own draw.
- Forgetting the fridge’s startup surge. The unit’s AC output must handle the compressor kicking on. Our refrigerator runtime guide explains it.
- Planning for hours when your risk is days. In hurricane and ice-storm states, the homes that get hit lose power far longer than the state average.
- Running a gas generator indoors or in the garage. It produces carbon monoxide, which can kill without warning. A battery power station is safe indoors; a generator never is.
A note from a physician: if someone at home depends on a CPAP, oxygen concentrator or refrigerated medicine such as insulin, the state average does not apply to you. Plan for the longest outage you could realistically face. The FDA recommends telling your electric company and fire department that you use a medical device that needs power, and checking the device’s settings when power returns, because many reset to defaults. If the device keeps someone alive, a battery is a bridge, not a plan: agree on where you will go with your clinician before storm season.
Frequently asked questions
Which state has the most power outages?
In 2024, South Carolina: its average home was without power for 52.3 hours, mostly during Hurricane Helene. Over the three years 2022–2024, Maine had the most, averaging 25.4 hours a year.
Which state has the most reliable power?
Washington, D.C. had the fewest hours without power in 2024 (0.5), followed by South Dakota (1.4) and Arizona (1.5). Over three years, D.C., Rhode Island and Delaware had the lowest averages.
Why were there so many outages in 2024?
Hurricanes. The EIA attributes about 80% of 2024’s hours without power to major events such as Hurricanes Beryl, Helene and Milton. Outages outside major events stay at roughly two hours a year.
What size power station do I need for a power outage?
For a fridge, Wi-Fi and lights, multiply the hours you want to cover by 105 and divide by 0.85. For most states that means about 1 kWh; for storm states, 2–3 kWh or more. Our sizing guide walks through other devices.
Does this data count every outage?
It counts sustained interruptions reported by utilities (for utilities that follow the IEEE standard, those longer than five minutes), averaged over all customers. Brief flickers are not included, and utilities that don’t use the IEEE method may classify events differently.
Can I use these figures?
Yes. Journalists, researchers and local officials are welcome to use the tables and the battery estimates. Please credit Tested Watts and link to this page. The underlying outage data is public and comes from the EIA.
This article is general information, not medical advice.
Ready to pick a unit? Compare options in our best power stations for home backup.
Sources
- U.S. Energy Information Administration, Electric Power Annual, Table 11.4: SAIDI values of U.S. distribution system by state, 2014–2024.
- U.S. Energy Information Administration, Hurricanes in 2024 led to the most hours without power in the United States in 10 years.
- Federal Energy Regulatory Commission, How Affordable and Reliable is Your Power?
- U.S. Food and Drug Administration, Home Health and Consumer Devices: power outages.
- U.S. Food and Drug Administration, Tips about medical devices and natural disasters.
- Centers for Disease Control and Prevention, Carbon Monoxide Poisoning Basics.