Portable power station runtime and sizing calculator

Pick your appliances and outage duration to see the battery watt-hours and inverter watts you need, then compare the three lowest cost-per-watt-hour stations from our live database.

You need about 1,127 Wh and 21 W continuous (21 W surge).

Raw appliance energy: 958 Wh over 12 hours at 85% usable AC capacity (average load 79.8 W).

Estimated runtime on ALLPOWERS R600 + 100W Solar Panel (299 Wh): 3.2 hours (assumes 85% usable AC delivery; real runtime varies by model, load and temperature).

1. Outage duration and AC conversion efficiency

Share of rated capacity that reaches your devices through AC. This is an assumption; real values vary by model, load and temperature.

2. Appliances to run during the outage

Source: U.S. DOE Building Technologies Office (Oak Ridge National Laboratory): Typical household refrigerators consume 1.5 to 2.0 kWh of electricity per day (1.5 kWh/day baseline).

Source: ResMed Battery Guide (Doc 198103/7, page 7): AirSense 10 with SlimLine tubing without humidifier at 10 cm H2O draws 0.93 A at 12 V DC (11.16 W, rounded to 11 W).

Source: Penn State EGEE 102 Table 2.2 Common Appliance Power Ratings: Wifi - Router rated 5 to 20 W (10 W typical).

Cheapest matching power stations by cost per Wh

Showing the 3 lowest cost-per-Wh stations out of 89 models meeting 1,127 Wh and 21 W. See all 89 matching stations on the main price table.

Three lowest cost-per-watt-hour power stations matching your calculated load
$/WhPriceCapacityOutputChemistryEst. runtimeProduct
$0.08$149
at ALLPOWERS Store, as of 2026-11-06
1,920 Wh2,500 WLiFePO420.4 h
$0.29$899
at Pecron Store, as of 2026-11-06
3,072 Wh3,600 WLiFePO432.7 h
$0.31$629
at FOSSiBOT Store, as of 2026-11-06
2,048 Wh2,400 WLiFePO421.8 h
How we calculated this

First, we sum the watt-hours used by each appliance row over the outage window. Cycling appliances like refrigerators and freezers use their daily kilowatt-hour rating scaled to the outage length (kWh/day × 1,000 × outage hours ÷ 24). Non-cycling appliances multiply running watts by the lesser of daily run hours or outage hours.

Second, we divide raw appliance energy by your chosen usable AC fraction (default 0.85) to account for inverter and battery conversion loss: required Wh = energy Wh ÷ usable fraction.

Third, continuous output watts sums the running watts of all rows assuming they run at the same time, and surge watts adds the single largest motor startup jump (surge W − running W) on top of continuous load.

Why refrigerators use daily kilowatt-hours instead of running watts times hours

A household refrigerator compressor cycles on and off throughout the day rather than drawing full power for 24 straight hours. Multiplying nameplate running watts by 24 overestimates required battery capacity by two to three times. Our calculator uses daily kilowatt-hour guidance from the U.S. Department of Energy and ENERGY STAR for refrigerators and freezers.

Related portable power station calculators

Check how many days your solar panels need to refill a battery in your state on our solar generator recharge time calculator, or compare grid recharge electricity rates against gasoline on our generator vs power station cost per kWh calculator.

Embed this runtime calculator on your site

Copy the HTML snippet below to embed the interactive portable power station runtime and sizing calculator on any webpage with a plain text attribution link back to Power Portable.

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  src="https://power-portable.com/embed/runtime?h=12&u=0.85&rows=fridge_full:1:24,cpap_no_humid:1:8,router:1:12"
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  height="540"
  style="border:1px solid #d0d7de;border-radius:4px;"
  title="Portable Power Station Runtime Calculator by Power Portable"
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<p><small>Source: <a href="https://power-portable.com/calculators/runtime">Power Portable Runtime Calculator</a></small></p>