What size power station do I need for home backup?

A power station can keep the important things in your home running through an outage, quietly and with no fumes. The catch is size. It holds a fixed amount of energy, so you have to pick what matters and size for it.

Step 1: add up a day of essentials

Size by watt-hours (Wh), not watts. Wh = watts × hours used.

Here's a typical "essentials" day. The watts come from Champion's wattage chart and our fridge guide, which uses ENERGY STAR data.

Item	Watts	Hours a day	Wh a day
Modern full-size fridge	averages 41–67 W	24	1,000–1,600
LED lights (about 8 bulbs)	100	5	500
Wi-Fi router and modem	15	24	360
Phones and a laptop	80	2	160
Total			about 2,000–2,600 Wh

Now allow for losses. Turning battery power into 120 V AC wastes some energy. We assume 85%.

Wh you need = daily Wh ÷ 0.85

Worked example

Take the middle of that table, about 2,300 Wh a day.

• 2,300 ÷ 0.85 = about 2,700 Wh for one day
• That's an average draw of about 2,300 ÷ 24 = about 100 W

A 2,048 Wh station runs that about 2,048 × 0.85 ÷ 100 = 17 hours. A 4,096 Wh station runs it about 35 hours. The calculator above is set to a 2,048 Wh station and a 100 W average.

Add a CPAP (about 480 Wh a night with no humidifier) or a TV for the evening (about 450 Wh for 3 hours at 150 W), and your number grows fast.

Step 2: pick a size

Station size	What it covers (estimate)
500 Wh	Phones, lights, router, or a CPAP for one night
1,000 Wh	A fridge for about 12–20 hours, or the essentials above for about 8–9 hours
2,000 Wh	The essentials above for most of a day
4,000–5,000 Wh	The essentials for about 1.5 to 2 days, plus room for a sump or well pump

Plan on the low end. A hot kitchen, an old fridge or lots of door opening all cut run time.

Step 3: check watts and surge

Wh tells you how long. Watts tell you what you can run at once.

• Continuous watts must be above everything running at the same time.
• Surge watts must be above your biggest motor's start. Champion lists 800–1,200 W to start a fridge and 1,300–2,150 W to start a 1/2 HP sump pump.

For example, the DELTA 3 Max Plus lists 3,000 W continuous and 6,000 W surge. The DELTA Pro 3 lists 4,000 W and 8,000 W. The Explorer 5000 Plus lists 7,200 W and 14,400 W.

Do you need 240 V?

You need a 240 V outlet if:

• you have a 240 V well pump. Most submersible well pumps are 240 V. See what size generator for a well pump for how to check yours.
• you want to feed chosen home circuits through a transfer switch or interlock.

On our list, the EcoFlow DELTA Pro 3 and Jackery Explorer 5000 Plus both have a 120/240 V L14-30R outlet. The DELTA 3 Max Plus is 120 V only.

A home connection must go through a transfer switch or interlock installed by a licensed electrician. Never plug a power station or generator into a wall outlet or dryer outlet to "backfeed" the house. It can electrocute a utility worker and start a fire. See interlock vs transfer switch.

What a power station can't do well

• Electric heat. A 1,500 W space heater drains a 2,048 Wh station in about 1.2 hours (2,048 × 0.85 ÷ 1,500).
• Electric water heaters, dryers and central AC. They draw thousands of watts for hours.
• Long outages with no recharge. Once the battery is empty, you wait for sun or a generator.

For those, a fuel generator does better. Many homes use both. See power station vs generator.

Features that help in an outage

• UPS switchover. Some stations take over automatically when the grid drops. EcoFlow lists under 10 ms for the DELTA 3 Max Plus and 10 ms for the DELTA Pro 3. Jackery lists under 20 ms (backup) for the 5000 Plus.
• Expansion batteries. Add capacity later. EcoFlow lists 2–10 kWh for the DELTA 3 Max Plus with extra batteries.
• Solar input. More input watts refill it faster in full sun. See how long it takes to charge a power station.

Before the next storm

1. Charge it to 100% when a storm is forecast.
2. Test a full day at home while the grid is still on. Note the battery percentage at the end.
3. Know your plan B for day two: solar, a car charger, or a generator.

If you recharge from a gas generator, run it outdoors only, 20+ feet from the house, away from windows and doors. Read our carbon monoxide guide.