What size generator do I need for home backup?

Check, uncheck or adjust the typical device list below — watts, startup surge and battery size update instantly. Numbers come from U.S. DOE, ENERGY STAR and manufacturer spec sheets, not marketing copy.

1. Check what you need to power

Refrigeration & Freezers

  • 1

Kitchen

  • 1

Heating, Cooling & Fans

Water & Pumps

  • 1

Laundry & Cleaning

Electronics & Office

  • 1
  • 1
  • 3

Medical Devices

Power Tools & Outdoor

Lighting

  • 4

2. Your sizing

Running load2,369 Wtypical certified-model range 2,358–2,378 W; we size with a conservative value
Startup peak4,569 Wdriven by 1× Sump Pump (1/3 HP)
Daily energy2,615 Wh
Recommended capacity3,270 WhBasis: 1 day of typical usage, incl. 25% margin for inverter loss & battery depth of discharge
Backup duration:

Assumptions: daily hours per device follow DOE / ENERGY STAR duty cycles; capacity adds a 25% margin. Check your appliance nameplates — actual draw varies by model.

3. Best matches from our 6-brand database

  1. Anker SOLIX F3800~$2,199
    • rated 6,000W covers your 2,610W continuous load
    • surge 9,000W covers your 4,569W start peak
    • 1.5 days of your typical daily use (3,840Wh / 2,615Wh)
    • 120/240V split-phase output
    Check price →
  2. EcoFlow DELTA Pro 3~$2,799
    • rated 4,000W covers your 2,610W continuous load
    • surge 8,000W covers your 4,569W start peak
    • 1.6 days of your typical daily use (4,096Wh / 2,615Wh)
    • 120/240V split-phase output
    Check price →
  3. EcoFlow DELTA 3 Max Plusexpandable system~$1,149
    • rated 3,000W covers your 2,610W continuous load
    • surge 6,000W covers your 4,569W start peak
    • base 2,048Wh + expansion batteries (up to 10,000Wh) covers your 3,270Wh need
    Check price →

Static answer (crawlable summary)

Typical device list: Refrigerator (top-freezer, ~16 cu ft)×1, Router + Modem×1, LED Bulb (60W equivalent)×4, Microwave Oven×1, Sump Pump (1/3 HP)×1, Phone / Smartphone Charger×3, TV (43-inch LED)×1.

Estimated from: Energy Star Certified Products · Mfr spec class: Netgear KB + measured (ARRIS SB8200) · Energy Star Certified Products (bulbs) · VT Extension table (DOE-derived) · Mfr spec: Zoeller M53 (FM2778) · Unbound Solar Power Table (secondary) — some household values are cross-checked class estimates (not single-model nameplates); check your own appliance nameplate before buying.

Continuous load2,369 W
Startup peak4,569 W (driven by 1× Sump Pump (1/3 HP))
Daily energy use2,615 Wh
Recommended capacity3,270 Wh (25% margin included)
Minimum inverter2,610 W continuous

Frequently asked questions

What size generator do I need for home backup?

For a typical setup (Refrigerator (top-freezer, ~16 cu ft), Router + Modem, LED Bulb (60W equivalent), Microwave Oven and Sump Pump (1/3 HP), plus 2 more devices), you need at least 2,369W of continuous power. The single biggest moment is startup: when 1× sump pump (1/3 hp) kicks on, the momentary draw peaks at 4,569W. For a full day of runtime we recommend at least 3,270Wh of battery capacity (your devices use about 2,615Wh per day, plus a 25% margin for a full day of use).

Which power stations can handle this?

Based on published specs, Anker SOLIX F3800, EcoFlow DELTA Pro 3, EcoFlow DELTA 3 Max Plus (with expansion batteries) cover the 4,569W startup peak and deliver 1.5 days / 1.6 days / up to 3.8 days fully expanded of typical daily use. Check the comparison cards above for the full numbers.

Why is the startup surge higher than the running watts?

Motor-driven devices (fridge compressors, well pumps, air conditioners) draw 2-5× their running power for a split second at startup — measured as locked-rotor amps (LRA). On this page the biggest spike comes from the Sump Pump (1/3 HP): a station that only meets the running load will trip or stall when it starts. Data sources: U.S. DOE Energy Saver, ENERGY STAR certified products, manufacturer spec sheets.

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