How to choose a portable power station

Buying guide · Last reviewed July 2026

Three numbers decide whether a power station will do what you want: capacity, continuous output, and surge headroom. Almost every disappointed owner got one of the last two wrong.

The three numbers, in order of importance

1. Continuous output (watts) — what you can run

This is the ceiling on what you can plug in at the same time. A 600W unit will not run a 1,500W kettle, no matter how large its battery is. Add up the running wattage of everything you want on at once, then add roughly 20% of margin.

Typical running draws, for reference:

2. Surge / peak output — the number people skip

Anything with a motor or a compressor draws several times its running wattage for a fraction of a second at start-up. A fridge that runs at 150W can spike past 900W the instant the compressor kicks in. If the unit cannot supply that spike, it shuts off — often silently, in the middle of the night.

3. Capacity (watt-hours) — how long it lasts

Watt-hours divided by the load's wattage gives you roughly the runtime in hours. A 1,000Wh unit running a 100W load lasts about ten hours in theory — call it eight in practice, once you account for inverter losses of roughly 10–15%.

Watch for capacity quoted in amp-hours instead. Amp-hours are meaningless without the voltage. A "100Ah" pack could be 1,280Wh at 12.8V or 5,120Wh at 51.2V. Multiply amp-hours by voltage to get watt-hours before comparing anything.

Battery chemistry: LiFePO4 versus lithium-ion

This is the single biggest change in the category over the past few years, and it is worth understanding because it affects what the product is worth to you over its life.

If the unit will sit at home and get cycled often, the extra weight of LFP is a good trade. If you are carrying it any distance and using it a few weekends a year, the cycle-life advantage may never pay off.

Four things buyers get wrong

Assuming the solar input rating is achievable

A "400W solar input" is the maximum the charge controller will accept, not what you will see. Real-world yield from a portable panel in good conditions is commonly 60–75% of its rating, and considerably less if the panel is flat rather than angled at the sun. Plan around the lower figure.

Ignoring recharge time from mains

Two units with identical batteries can differ enormously here — some take over eight hours from a wall socket, others under two. If the use case is rolling blackouts, recharge speed matters as much as capacity.

Not checking whether pass-through charging is supported

Pass-through means you can charge the unit while it powers something. Not every model allows it, and some that do will not do it at full input power. For a desk UPS-style setup this is essential; for camping it rarely matters.

Overlooking the inverter waveform

A pure sine wave inverter is standard on reputable units now, but modified sine wave models still exist at the budget end. Sensitive electronics — medical equipment, some motors, certain chargers — can misbehave or buzz on modified sine. If a listing does not say "pure sine wave", assume it is not.

Before you buy: a checklist

• Add up the running watts of everything you will run at once, then add 20%.
• Identify anything with a motor or compressor, and confirm the surge rating covers it.
• Convert any amp-hour figure to watt-hours before comparing across models.
• Check the chemistry, and whether the rated cycle life matches how often you will actually cycle it.
• Confirm mains recharge time, not just solar input.
• Confirm pure sine wave output if you are running anything sensitive.
• Check whether pass-through charging is supported, if you need it.
• Read the warranty term and, more importantly, who honours it in your country.