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What size power station do I need to run a sump pump during an outage?

Q: What size power station do I need to run a sump pump during an outage?

Plan on a power station with at least 6300 watt-hours of capacity and 800W continuous / 1500W surge output to run this for 6 hours. A Expandable home backup (≈6,000Wh+) covers it, running the load about ~5.7 h on a charge.

A sump pump during a storm outage is a surge problem more than an energy problem: it sits idle, then slams on against a full pit. The station has to handle the start-up surge every cycle and hold enough energy for however long the storm keeps the pit filling.

The load

Sump pump (1/3 HP) — 800W running, 1500W starting

POWER PLATE1 LOAD · 6 H RUNTIME

Continuous draw

800 W

Startup surge

1,500 W

Energy for 6 h

5,647 Wh

Buy at least

6,300 Wh

Look for ≥6,300Wh capacity, ~800W continuous / 1,500W surge or better.

Field note: Size to the surge first — a station that can't restart the pump is a flooded basement with a charged battery next to it. Because the pump only runs in short bursts, a midsize station's energy often lasts far longer than the raw runtime math suggests. A dedicated battery backup sump system is the purpose-built alternative worth comparing.

Right size: Expandable home backup (≈6,000Wh+) · 5,000W

Typical price $3,500-6,000+ · e.g. EcoFlow Delta Pro Ultra, Bluetti AC500 + B300S (stackable)

Backing up whole circuits through a transfer switch; add battery modules for days of autonomy, especially with solar. A home-backup system, not a grab-and-go unit. For 240V loads or true whole-home coverage, compare against a standby generator.

Runs this load ~5.7 h on a full charge.

See current prices on Amazon

This is a heavy or long load for battery power — plan on solar recharge or compare a fuel generator.

Adjust for your setup

Different loads or runtime? Uncheck and re-check below and drag the runtime slider — the plate recomputes live.

POWER PLATE1 LOAD · 6 H RUNTIME

Continuous draw

800 W

Startup surge

1,500 W

Energy for 6 h

5,647 Wh

Buy at least

6,300 Wh

Look for ≥6,300Wh capacity, ~800W continuous / 1,500W surge or better.

Capacity includes inverter loss (~15%) and a usable-charge margin, so the station isn't run flat. A solar panel or vehicle charge extends runtime past this number.

How long do you need to run it? 6 h

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Electronics TV (55" LED) 80W run Wi-Fi router + modem 15W run Laptop 65W run Desktop PC + monitor 350W run / 400W start Phone charger 10W run Starlink dish + router 75W run / 100W start

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Lighting LED lights (per room) 30W run

Laundry Washing machine 700W run / 1600W start Clothes dryer (electric) 5000W run / 6000W start Clothes dryer (gas) 700W run / 1800W start

Household Garage door opener (1/2 HP) 550W run / 1200W start Water heater (electric tank) 4500W run EV charging (Level 1, 120V) 1400W run

Tools & outdoor Circular saw 1400W run / 2300W start Air compressor (1 HP) 1500W run / 3000W start Welder (140A MIG) 3500W run / 4000W start

RV & camping RV air conditioner (13,500 BTU) 1300W run / 2900W start RV converter/charger 500W run Electric griddle 1200W run Slow cooker 250W run

Power stations that fit

Right size: Expandable home backup (≈6,000Wh+) · 5,000W

Typical price $3,500-6,000+ · e.g. EcoFlow Delta Pro Ultra, Bluetti AC500 + B300S (stackable)

Runs this load ~5.7 h on a full charge.

See current prices on Amazon

This load is heavier or longer than portable stations cover well. Add solar recharge, shorten the runtime, or look at a fuel generator for sustained high-wattage loads.

This site earns commissions from qualifying purchases made through links to Amazon and other retailers, at no extra cost to you. Wattage figures are typical estimates — actual draw varies by model. Always verify against your appliance's nameplate, and consult a licensed electrician for any panel or hardwired connections.