Power station runtime calculator
Choose a power station, or enter your own battery size, then add what you'll plug in. You'll see whether the inverter can handle it and how long one full charge lasts.
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What you'll plug in
- Full-size refrigerator (ENERGY STAR)160 W, cycles 32% of the time
- Wi-Fi router6.5 W
- LED bulb (60 W equivalent)9 W
- Smartphone charger10 W
Runs all of it for about 8.3 h on a full charge.
- Runtime
- 8.3 h
- Running watts
- 214of 1,800 W inverter
- Start-up peak
- 214of 3,600 W surge
- Average draw
- 105W after cycling
Runtime = 85% of the battery's rated Wh (usable after inverter and DC losses) ÷ the average draw. The start-up peak assumes one motor starts at a time.
Smallest stations that run this load
| Station | Battery | Inverter | Runtime | Buy |
|---|---|---|---|---|
| EcoFlow RIVER 3 | 245 Wh | 300 W | 2.0 h | Amazon |
| EcoFlow RIVER 3 Plus | 286 Wh | 600 W | 2.3 h | EcoFlow |
| BLUETTI Elite 30 V2 | 288 Wh | 600 W | 2.3 h | BLUETTI |
| Jackery Explorer 300 Plus | 288 Wh | 300 W | 2.3 h | Amazon |
| BLUETTI AC50B | 448 Wh | 700 W | 3.6 h | BLUETTI |
| Goal Zero Yeti 500 | 499 Wh | 500 W | 4.1 h | Goal Zero |
| DJI Power 500 | 512 Wh | 1,000 W | 4.2 h | DJI |
| OUPES Exodus 700 | 576 Wh | 700 W | 4.7 h | OUPES |
How the estimate works
Runtime is usable energy divided by average draw. A station's rated watt-hours describe the cells, not what reaches your outlet: the inverter and DC converters turn some of it into heat. We count 85% of the rated capacity as usable, a typical figure for a modern pure-sine inverter at moderate load. Very light loads, like a router on a big station, can come in lower because the inverter's own idle draw becomes a larger share.
Fridges, freezers and furnace fans run on a cycle, so we use their average draw rather than the running watts. Appliance figures come from our appliance wattage table, where every row links to its source. To compare stations by spec, see the power station rankings.
Frequently asked questions
How do I calculate how long a power station will last?
Multiply the battery's watt-hours by about 0.85 to allow for inverter losses, then divide by the total watts you plug in. A 1,000 Wh station running a 100 W load lasts roughly 8.5 hours.
Why does a fridge last longer than its wattage suggests?
A fridge compressor cycles on and off, so it only draws its running watts part of the time. We use each fridge's duty cycle to work out its average draw.
What is surge watts, and why does it matter?
Motors and compressors pull two to three times their running watts for a moment when they start. If that spike is above the station's surge rating, the inverter shuts off even though the running watts would fit.
Can I run several appliances at once?
Yes, as long as their combined running watts fit the inverter's continuous rating. The calculator adds them up and checks the start-up peak assuming one motor starts at a time.