What size generator do i need for my trailer?

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

Kitchen

Heating, Cooling & Fans

Water & Pumps

Laundry & Cleaning

Electronics & Office

Medical Devices

Power Tools & Outdoor

Lighting

  • 3

2. Your sizing

Running load3,189 W
Startup peak8,589 Wdriven by 1× RV Rooftop AC (13,500 BTU)
Daily energy16,115 Wh
Recommended capacity20,150 Whincludes 25% margin for inverter loss & battery depth of discharge

3. Best cross-brand matches

No single portable power station covers this load — look at expandable systems (e.g., EcoFlow DELTA Pro 3 + extra battery, Anker SOLIX F3800 expansion packs) or a fixed home battery instead.

Static answer (crawlable summary)

Typical device list: RV Rooftop AC (13,500 BTU)×1, Portable 12V Fridge/Freezer (Dometic CFX3 45 class)×1, LED Bulb (60W equivalent)×3, Phone / Smartphone Charger×2, Electric Kettle×1, Starlink Mini×1.

Continuous load3,189 W
Startup peak8,589 W (driven by 1× RV Rooftop AC (13,500 BTU))
Daily energy use16,115 Wh
Recommended capacity20,150 Wh (25% margin included)
Minimum inverter3,510 W continuous

Frequently asked questions

What size generator do i need for my trailer?

For a typical setup (rv rooftop ac (13,500 btu), portable 12v fridge/freezer (dometic cfx3 45 class), led bulb (60w equivalent), phone / smartphone charger and electric kettle), you need at least 3,189W of continuous power. The single biggest moment is startup: when 1× rv rooftop ac (13,500 btu) kicks on, the momentary draw peaks at 8,589W. For overnight runtime we recommend at least 20,150Wh of battery capacity (your devices use about 16,115Wh per day, plus a 25% margin).

Which power stations can handle this?

Look for a station whose surge rating covers 8,589W and whose capacity is at least 20,150Wh.

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). A generator that only meets the running load will trip or stall when the biggest motor starts. Our data sources: U.S. DOE Energy Saver, ENERGY STAR certified product database, and manufacturer spec sheets (Franklin Electric, Goodman, Zoeller).

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