Do I need power factor for this calculator?

No. This screen uses watts and watt-hours for consumer stations. PF matters for UPS kVA and generator kVA sizing—use those tools when you are sizing inverter kVA, not portable Wh.

Portable Power Station Size Calculator

Estimate required Wh and screen continuous / surge watts for Jackery-, EcoFlow-, and Bluetti-class stations—instant sizing for outage and camping loads.

Calculator

Scenario: pick a use case and check devices (energy = Σ W×h). Quick: edit continuous watts × hours directly. Advanced: η, buffer, surge.

Use-case scenario Loads a device checklist. Uncheck all devices to use Quick watts × hours only.

Device checklist

Add custom loads by editing watts/hours on a checked row, or clear checks and enter totals below.

Continuous load (W) Sum of devices running at the same time. Example: 80 W fridge average + 60 W TV + 60 W misc ≈ 200 W.

Target runtime (hours) How long you need that continuous load. Overnight fridge often 6–10 h; camping evenings 3–5 h.

Energy buffer (%) A user-defined planning assumption. Do not double-count reserve already excluded from an OEM usable-Wh rating.

Inverter / path efficiency η Use the applicable measured or OEM curve for the load and output path. Default 0.90 is an editable example.

Peak / surge load (W) Motor or compressor start. Must fit the station’s surge or pass-through rating—not the continuous rating alone.

About this calculator

Screens portable power station Wh and watt ratings from load and hours. It is not a UPS kVA selector and not a generator sizing tool. Decide UPS vs station in portable power vs UPS; for IT bridge minutes use UPS runtime. Browse the backup power calculator hub or the UPS calculator hub.

Calculation Results

≈ 1067 Wh usable energy needed

Minimum screen: ≥1067 Wh · continuous ≥200 W · surge ≥200 W, subject to the OEM capacity and rating definitions.

Assumptions: constant average watts and user-entered η/buffer. Confirm whether the OEM publishes nominal or usable Wh; do not count hidden BMS reserve twice. Temperature, rate effects, and cutoffs are not modeled.

Continue Your Calculation

Need UPS bridge minutes for PCs or networking instead of hour-scale Wh? Continue in UPS Runtime.

UPS runtime →

Planning disclaimer

Screening estimate only. Confirm continuous watts, surge, usable Wh, waveform (pure sine), and recharge options on the manufacturer datasheet. Whole-home multi-circuit backup usually needs a generator and listed transfer method—not a suitcase station alone.

Wh quick reference (η 0.9 · 20% buffer)

Required Wh ≈ (W × hours ÷ 0.9) × 1.2. Open a row to load the calculator.

Load	Hours	≈ Required Wh
	8 h	≈ 1067 Wh
	4 h	≈ 1067 Wh
	6 h	≈ 1250 Wh
	3 h	≈ 2000 Wh
	12 h	≈ 1280 Wh

Formula & explanation

Wh_required = (W_continuous × hours ÷ η) × (1 + buffer)

Compare published specifications against all three calculated requirements: energy capacity ≥ Wh_required, continuous watts ≥ W_continuous, and surge watts ≥ the entered peak starting load. Confirm whether the manufacturer states nominal or usable Wh before comparing capacity.

Why no PF? This tool sizes energy (Wh) and AC continuous watts for consumer stations. Power factor belongs in UPS capacity (kVA) and generator sizing—different decision.

W — simultaneous running watts (nameplate or measured).
hours — planned runtime at that average load.
η — inverter / conversion efficiency (≤ 1).
buffer — documented user assumption; do not double-count reserve already excluded from usable Wh.

Example: 200 W × 4 h ÷ 0.9 × 1.20 ≈ 1067 Wh. The selected product must meet or exceed this energy screen and separately meet the continuous and surge watt requirements.

Shortest chain: load watts → Wh screen (this page) → compare vs UPS in portable power vs UPS → IT minutes in UPS runtime → optional generator size for multi-circuit outages.

What can common watt ratings run?

PAA-style guide: continuous rating limits what you can plug in; Wh limits how long.

Continuous rating	Typical loads	Not ideal alone
~300–500 W	Phones, Wi-Fi, LED lights, laptop	Hair dryer, space heater, large microwave
~1000 W	TV, small fridge (check surge), CPAP, camping kit	Whole-home HVAC, EV charging, well pump
~2000 W	Multiple appliances, induction hot plate (short bursts)	Central AC, dryer, continuous high heat
Generator path	Multi-circuit / whole-home via transfer switch	Suitcase station as sole whole-home source

Frequently Asked Questions

How do I size a portable power station?

Wh ≈ (W × hours ÷ η) × (1 + buffer). Example: 200 W for 4 h at η 0.9 with 20% buffer ≈ 1067 Wh. Then match continuous and surge watts on the datasheet.

What size portable power station do I need?

Sum simultaneous watts, multiply by hours, divide by the applicable path efficiency, and apply a documented buffer. Select only a product whose stated Wh basis, continuous watts, and surge watts each meet the calculated requirement.

What will a 1000W portable power station run?

Loads at or under 1000 W continuous (lights, laptop, TV, many small fridges). Runtime still depends on Wh: 1000 Wh at 200 W and η 0.9 ≈ 4.5 h before buffer.

Is a power station the same as a UPS?

No. UPS = short clean bridge for IT; station = hour-scale Wh. See portable power vs UPS.

Do I need power factor here?

No for Wh screening. Use UPS capacity or generator size when you need kVA.

How big a power station for one camping night?

Example: LED 10 W×4 h + fridge 80 W×10 h + phone 20 W×3 h → Σ energy 900 Wh. At η 0.9 and 20% buffer: Wh ≈ 1200 → shop the 1000–1200 Wh class and confirm surge for the fridge compressor.

How do I estimate fridge energy use?

Use average running watts × hours (duty cycle), not nameplate start watts, for Wh. Enter compressor surge separately so the inverter peak rating is checked.

How long will 500 W continuous last?

Runtime still depends on Wh. Example: a 1000 Wh pack at 500 W and η 0.9 lasts roughly 1000×0.9÷500 ≈ 1.8 h before buffer—raise Wh or lower load for longer nights.