Pair your load with the right power.

What should you actually keep running during a power outage?

Scenarios Updated 2026-08-01

Rank by watt-hours per day, not by how important the appliance feels. On that ranking the things people worry about most — keeping food cold, keeping the internet up, keeping a medical device running overnight — are all cheap, and several of them together fit inside one mid-size battery for a day or more.

Anything that makes heat is in a different category entirely. A single electric space heater will empty a large portable power station in about an hour, which is why heat during an outage is a fuel problem rather than a battery problem.

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What each load actually costs in a day

Watt-hours per day, the loads people ask about

Published daily-energy figures where the record has one, and running watts where the answer depends entirely on how long you use it. A battery is sized against this column, not against the wattage on the appliance label.

Router and modem — running 9.1 W Official spec · verified 2026-08-01 · high confidence

The load nobody plans for and everyone wants. It runs continuously, so its daily figure is simply this times twenty-four.

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Router and modem — per day 218.4 Wh Derived by WattPair

Running watts times the 24 h a day this record states it operates for. Both figures are on the load record.

CPAP machine — per night 176 Wh Official spec · verified 2026-08-01 · medium confidence

One night with humidification, from the manufacturer’s own power-consumption table. Turning the humidifier off cuts it sharply.

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Chest freezer — per day 616 Wh Official spec · verified 2026-08-01 · medium confidence

Cheaper than the refrigerator, and it holds its temperature far longer unopened.

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Full-size refrigerator — per day 1,123 Wh Official spec · verified 2026-08-01 · medium confidence

The single largest of the sensible loads, and still under a kilowatt-hour and a half.

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Electric space heater — running 1,500 W Official spec · verified 2026-08-01 · high confidence

Continuous, not cyclic. In a single hour this one load uses more than the refrigerator uses in a day.

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officialverified 2026-08-01appliance records

What that buys on a real machine

Put those figures against one record and the ranking becomes obvious. BLUETTI Elite 200 V2 runs the refrigerator for 28 h and the same machine runs the space heater for 1.1 h. A far smaller machine, BLUETTI Elite 30 V2, keeps the router and modem alive for 14 h. Nothing about the batteries differs; the loads do.

A priority order that survives contact with a real outage

  1. Anything medical, first and without debate — and check what the device maker says about running it from an inverter before the outage, not during it.
  2. Communications. A router and modem cost almost nothing to run and are what let you find out how long the outage will last, report it, and reach someone. This is the load every competing guide forgets.
  3. The freezer, then the refrigerator — and in that order, because a full freezer holds temperature for a day or more unopened while a fridge does not. Cycling them for a few hours at a time is usually enough; neither needs continuous power.
  4. Light, at whatever wattage LED lighting costs, which is negligible against everything above and worth doing properly rather than with phone torches.
  5. Heat and cooling last, and honestly. Resistive heating and air conditioning are outside what a portable battery does for more than an hour or two. Layered clothing, a sealed room, or a fuel-burning heater with proper ventilation are the answers here; a bigger battery is not.

Where to go next

Questions people ask

How do I keep food cold during a power outage?
Open the doors as little as possible and cycle the compressor rather than running it continuously. A full-size fridge on our records costs a little over a kilowatt-hour a day if it runs the whole time, and much less if you power it in bursts — the box holds cold, and the compressor only has to make up what leaked out.
How do I keep internet during a power outage?
A router and modem together draw about as much as a bright light bulb, so a small power station covers them for most of a day. The limiting factor is usually your provider’s equipment rather than yours: fibre and cable networks have their own backup arrangements, and a mobile hotspot is the fallback when they run out.
What can I run during an outage with a 1000Wh power station?
On the daily figures above: a fridge, a router and a CPAP machine, at the same time, for most of a day — with the fridge cycling rather than running flat out. What you cannot do is add a space heater, which alone would consume the whole battery in under an hour.