CALL US TODAY
Open M-F, 9-5 CST
How Many Watts Does a Sump Pump Use? Amps, Generators, and Battery Backup
A typical 1/3 to 1/2 HP sump pump draws about 9.4 to 9.7 amps at 115 volts, or roughly 1,100 watts while it runs. It pulls more for a split second when the motor starts. Because a sump pump only runs when the pit fills, it uses little energy per day, which makes it one of the easiest loads to back up with a generator, a power station, or a home battery.
Sump pump wattage and amps (real specs)
Here is what Zoeller, one of the best-known sump pump makers, lists in its technical data sheets:
| Model | HP | Volts | Amps | Volts x amps |
|---|---|---|---|---|
| Zoeller M53 / M57 | 3/10 HP | 115V | 9.7 A | About 1,115 VA |
| Zoeller M98 | 1/2 HP | 115V | 9.4 A | About 1,081 VA |
| Zoeller D53 / D57 | 3/10 HP | 230V | 4.8 A | About 1,104 VA |
Source: Zoeller technical data sheets FM2778 (50 series) and FM2779 (Model 98).
Why "VA" and not watts? Volts x amps gives volt-amps (VA). On a motor, the true watts are a bit lower than VA. For sizing a generator, inverter, or power station, use the VA number. It is the safer one.
Starting surge: any motor pulls several times its running current for a moment when it starts. Make sure your backup power has a surge rating well above the pump's running watts, and test it before a storm.
Find your own number: the amps are printed on the pump's label and in its manual. Multiply by 115 (or 230) to get VA.
How many amps does a sump pump use?
About 9.4 to 9.7 amps for the common 115V Zoeller models above, and about 4.8 amps for the 230V versions. Notice the 1/2 HP M98 is rated slightly lower than the 3/10 HP M53. Horsepower alone does not tell you the draw, so check the label.
How much electricity does a sump pump use per day?
It depends on how often it runs, which depends on rain and your water table. The math is simple:
Watts x minutes of pumping per day / 60 = Wh per day
Example: a 1,100 watt pump that runs 2 minutes an hour during a storm runs 48 minutes a day. 1,100 x 48 / 60 = 880 Wh (0.88 kWh) per day, about 15 cents at 17 cents per kWh. In dry weather it may not run at all.
What size generator do you need for a sump pump?
The pump alone is small. A generator with about 2,000 running watts or more runs it, as long as the starting surge is covered. Most sump pumps plug into a regular outlet, so you can run one from the generator with a heavy-duty outdoor extension cord rated for the load. Keep the generator outside, away from doors and windows.
- DuroMax XP5500HX: 5,500 starting / 4,500 running watts on gasoline, CO alert shutoff. Runs the sump pump plus a fridge, freezer, and lights. $629
- DuroStar DS8000iX: 8,000 starting / 6,500 running watts, inverter power, L14-30 outlet for a transfer switch or interlock. Add a furnace blower and more of the house. $999
For whole-house sizing, see What Size Generator Do You Need to Run a House?
Sump pump battery backup: your options
Outages and heavy rain often hit at the same time, so many homes add battery backup. There are three ways to do it:
- A dedicated DC backup pump. A second, battery-powered pump sits in the pit and takes over if the main pump loses power or fails. It is the classic setup, but it only pumps water.
- A portable power station. Plug your existing pump into it during an outage. It also runs a fridge, lights, and Wi-Fi.
- A home battery system. Wired into your panel through a transfer switch, it keeps the sump pump circuit and other essentials running automatically. See our battery backup for home systems.
How long will a power station run a sump pump?
| Power station | Capacity / output | Continuous pumping (1,100 W) | Coverage at 2 minutes of pumping per hour | Price |
|---|---|---|---|---|
| Jackery HomePower 3000 | 3,072 Wh / 3,600 W (7,200 W surge) | About 2.5 hours | About 75 hours | From $1,349 |
| Jackery Explorer 2000 v2 | 2,042 Wh / 2,200 W | About 1.7 hours | About 50 hours | From $899 |
Hours = capacity x 0.9 / 1,100 W. Coverage assumes the pump runs 2 minutes out of every hour, and the pump is the only load. Capacity, output, and surge are from each product page. The HomePower 3000's 7,200 W surge rating gives a sump pump motor plenty of room to start. With any power station, plug the pump in and let it cycle once before you count on it.
Need help sizing? Call 1-888-855-7286. Send us the amps from your sump pump's label and what else you want running, and we will match you to a generator, power station, or home battery.
Sump pump wattage FAQ
How many watts does a sump pump use? About 1,100 watts (volts x amps) for a common 1/3 to 1/2 HP pump. Zoeller rates its M53 at 9.7 amps and its 1/2 HP M98 at 9.4 amps, both at 115V.
How many amps does a sump pump draw? About 9.4 to 9.7 amps at 115V for the Zoeller models above, or 4.8 amps for 230V versions.
Will a 2,000 watt generator run a sump pump? Usually, for the pump alone, as long as its starting surge is covered. A bigger generator lets you run the fridge and lights at the same time.
Can a portable power station run a sump pump? Yes. Choose one with a high surge rating, like the Jackery HomePower 3000 (7,200 W surge), and test it with your pump before a storm.
How long will a battery run a sump pump? Divide the battery's usable watt-hours by the pump's watts for continuous pumping time. Since the pump only runs part of each hour, real coverage is much longer. A 3,072 Wh station covers about 75 hours at 2 minutes of pumping per hour.