Guides · Updated October 12, 2026
What size power station runs a sump pump?
A typical 1/3 HP sump pump draws about 800 W while pumping but needs roughly 2,000 W to start, so you need a unit rated for at least 2,000 W surge. On a wet day it runs maybe 4 hours in total, about 1,000 Wh. Capacity is rarely the problem; the surge rating is.
Which units clear the surge
The 300 to 700 Wh class tops out at 1,000 to 1,500 W surge and will trip. From the 1 kWh class up, every unit we cover is rated for 2,700 W surge or more: the Bluetti Elite 100 V2 (2,700 W), EcoFlow DELTA 3 (3,600 W) and Jackery Explorer 1000 v2 (3,000 W). A 1/2 HP pump can spike past 2,500 W, so for those step up to a 2 kWh unit with 4,000 W or more of surge, like the EcoFlow DELTA 3 Max or Jackery Explorer 2000 v2.
How long the battery lasts
Pump runtime depends entirely on how much water is coming in. At 10 minutes of pumping per hour, a 1 kWh unit lasts about 7 hours and a 2 kWh unit about 13 hours. In a heavy storm with the pump cycling every few minutes, halve those numbers.
Set it up before the storm
- Keep the power station on a shelf above the floor, plugged into the wall with pass-through charging on, and the pump plugged into the station. If the grid drops, the pump keeps running with no action from you.
- Units with a UPS or EPS mode switch over in 10 to 30 milliseconds, fast enough that the pump never notices.
- A water-powered or battery backup sump pump is still worth having for a multi-day outage.
The units that fit
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DELTA 3 Max
Cheapest unit that runs Sump pump for about 1.7 days.
Explorer 2000 v2
Lighter and smaller, and still covers it for about 1.7 days.
C2000 Gen 2
Extra headroom: about 1.7 days on one charge, and it accepts add-on batteries.
Prices are each brand's list price on October 12, 2026; buy links go to Amazon, where the price can differ. Adjust the devices and days in the finder for your own numbers, or see all 20 models.
Common questions
Can I run the sump pump and the fridge together?
Yes on anything 1,800 W or more. The fridge adds about 150 W running and 1,200 W starting; the two surges rarely land at the same instant, but a 3,000 W or higher surge rating gives margin.