
Best for Sump Pumps
Backup Power for a Sump Pump
The strongest case for backup power there is. Three approaches, compared on real runtime.
Top pick: Zoeller 508-0006 AquaNot Spin 508 ProPak
Watt & Warden
Before you buy anything, it is worth knowing what an outage actually does. Most of the damage is not the darkness — it is the freezer, the basement and the surge when the power comes back.

The power is out right now. Here is the sequence — the first four things, in order, most of which cost nothing.
You have a basement. A sump pump with no power is the single most expensive failure in this whole category. Start there.
You are new to all of this. Backup power for beginners is the plain-language version with no jargon and no assumed knowledge.

Best for Sump Pumps
The strongest case for backup power there is. Three approaches, compared on real runtime.
Top pick: Zoeller 508-0006 AquaNot Spin 508 ProPak

Best for Router and Modem
About 20W of load, which makes this the cheapest useful purchase in backup power.
Top pick: APC Back-UPS BE600M1

Guide
The first ten minutes, in order. Most of it is free and none of it requires equipment.
Top pick: Jackery Explorer 300 Plus

Guide
Eleven hours a year on average -- an average that describes almost nobody. Find your own.
Top pick: BLUETTI AC180

Guide
The outage is not the dangerous part. The sag before and the surge after are.
Top pick: CyberPower CP1500PFCLCD

Guide
No jargon, no assumed knowledge. Watts, watt-hours and what each machine actually does.
Top pick: Jackery Explorer 300 Plus

Guide
Powering your router is the easy half. The street equipment is the half you do not control.
Top pick: APC Back-UPS BE600M1
The EIA's Electric Power Annual for 2024 records an average of eleven hours without power per U.S. customer across the year — the highest in a decade, and roughly twice the average of the preceding ten years. But that single figure conceals two completely different events.
About two of those hours were ordinary faults: a tree on a line, a failed transformer, a car into a pole. They last minutes to a couple of hours, they are annoying, and they cost you nothing. Nearly nine hours came from major events, and in 2024 Hurricanes Beryl, Helene and Milton alone accounted for 80% of all outage hours nationally. Those are the multi-day events, and they are where the money goes. Customers in South Carolina averaged nearly 53 hours in 2024; customers in Arizona, the Dakotas and Massachusetts averaged under two.
The practical consequence: your local history matters more than the national average. A household in a hurricane corridor and a household in Phoenix are solving different problems and should buy different things.
In rough order of expense, and none of it is the inconvenience of the dark:
Before any purchase: keep the fridge and freezer shut, and know in advance which items you would move between them. Unplug sensitive electronics as soon as the power goes, not when it returns — the damaging surge arrives on restoration. Fill a bath if you are on a well pump, because no power means no water at all. Know where your main breaker is, and know that if you have a gas water heater you probably still have hot water for a while.
The other free move is knowing your own outage history. Your utility publishes it, and so does its regulator. Fifteen minutes finding out whether your street loses power for two hours twice a year or for three days every other winter will save you more money than any review on this site.
Once you know the shape of your outages, the equipment decision is nearly automatic. Hours: a battery, and a modest one. Overnight: a larger battery, or a small generator. Days: a generator, dual fuel, with a transfer switch and a fuel plan. That mapping is what the duration and capacity page exists to make precise.
What we will not do is sell you a machine for a scenario you do not have. If your power goes out for ninety minutes twice a year, the right purchase is a $200 battery and a working flashlight, and anyone telling you otherwise is selling something.
The USDA's guidance is about 4 hours for a refrigerator, 48 hours for a full freezer and 24 hours for a half-full one -- all assuming the door stays closed. Opening the door repeatedly to check is what usually causes the loss.
Yes, and do it at the start rather than the end. The damaging voltage spike typically arrives when power is restored, not when it fails. Unplug computers, televisions and anything with a sensitive power supply, and leave one lamp plugged in so you know when the power is back.
If you are on a private well, immediately -- the pump is electric, so you have no water at all beyond what is in the pressure tank. On municipal water you usually keep pressure for a while, though extended regional outages can affect treatment and pumping stations and trigger boil-water notices.
Not sure which of these you need? Work out the number first — capacity falls out of how long your power is usually off, not out of a budget.