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Well pump 3/4 HP: how much battery you need1

Well pump 3/4 HP draws about 1200 W (1200 W range), runs 100% of the time and uses 1200 Wh per day. Start-up surge: 3000 W.

Estimate between the 1/2 HP and 1 HP charts: about 1,000–1,500 W running and 2,500–4,500 W to start. The nameplate amps × volts is the final word.

Battery needed

HoursWhBattery (Wh)Inverter (W)
For 8 hours4006071320 / 3000
For 24 hours120018191320 / 3000
For 72 hours360054551320 / 3000

Open in calculator with this appliance →

Stations that fit (24 h)

Grecell 2400W Portable Power Station
1843.2 Wh · 2400 W (4800 W peak)
→
Allpowers R2500
2016 Wh · 2500 W (4000 W peak)
→

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FAQ

How many watts does a Well pump 3/4 HP use?

Typically 1200 W while running, with a range of 1200 W depending on model and age. Start-up surge can reach 3000 W.

How long will a 1000 Wh power station run a Well pump 3/4 HP?

About 0.6 hours on the clock, allowing for the 100% duty cycle, inverter losses and a 20% reserve.

What size power station do I need for a Well pump 3/4 HP overnight (8 h)?

About 607 Wh of battery and an inverter rated at least 1320 W continuous with 3000 W surge.

Can I run a Well pump 3/4 HP on solar during an outage?

You need roughly 800 W of panels in winter to replace a day's use (1200 Wh), charging through a station with a big enough MPPT input.

Other sizes

1/2 HP880 W1 HP1500 W1.5 HP2100 W1

Other appliances

Sump pump 1/3 HP650 WSump pump 1/2 HP920 WSewage ejector pump 1/2 HP1000 W1Electric water heater (tank)3750 WWater softener (control valve)10 W1

1 Approximate values: estimated from motor or heater power and typical figures published online, not from a manufacturer chart. Check your appliance label.

Inverter efficiency 88%, usable depth of discharge 90%, reserve 20%. Full method: How we calculate.