What size portable power station do I need?

Updated Oct 3, 2026

Choosing a power station comes down to two questions. Can it power everything at once? That's output, in watts (W). For how long? That's capacity, in watt-hours (Wh). Get those right and the rest is preference.

Step 1: List what you'll plug in

Find each device's wattage on its label or power adapter. Typical figures: phone 10–20 W, laptop 45–100 W, CPAP 30–90 W, Starlink 50–75 W, full-size fridge ~150 W running, microwave ~1,500 W from the outlet, space heater 1,500 W.

Step 2: Check output (watts)

Add up the watts of everything that will run at the same time. The station's continuous output must be higher. Then check motors and compressors (fridges, pumps, power tools, AC units): their brief startup surge must fit within the station's peak rating.

Rule of thumb: under 300 W for electronics only, 600–1,000 W for small appliances, 1,800 W or more for kitchen appliances, sump pumps and most home backup.

Step 3: Check capacity (watt-hours)

For each device, multiply watts by hours of use per day, then add them up. Divide by 0.85 to cover conversion losses. That's the minimum capacity for one day.

Example: weekend camping. Phones (2 × 15 W × 2 h = 60 Wh) + LED lights (30 W × 5 h = 150 Wh) + laptop (60 W × 3 h = 180 Wh) = 390 Wh a day. Divided by 0.85 that's about 460 Wh, so a 500–800 Wh station, or a smaller one plus a solar panel.

Example: outage backup. Fridge (~1,260 Wh a day) + router and modem (20 W × 24 h = 480 Wh) + phones (60 Wh) = about 1,800 Wh a day. Divided by 0.85 that's about 2,100 Wh, so a 2 kWh station, or a 1 kWh station plus solar or an extra battery.

Leave headroom

Batteries lose some capacity over the years, and real-world use is rarely as tidy as a list. Sizing 20–30% above your estimate avoids disappointment, and buying a model that accepts extra batteries lets you grow later.

Quick guide by size

  • Compact (under 500 Wh, 7–11 lb): phones, laptops, lights, CPAP, camera gear. See best for camping.
  • Mid-size (500–1,500 Wh, 17–35 lb): a fridge for a day, small kitchen appliances, power tools.
  • Large (1,500+ Wh, 45 lb+): multi-day outages, RVs, running several appliances. See best for home backup.

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