Size My Backup

Power station to work from home in an outage

A laptop, a router and a lamp need very little power. The big question is how many hours you need, and whether your internet itself stays up (a cable or fibre box needs power at the street too, which a station at home cannot supply; phone hotspot is the usual fallback).

Typical numbers

ItemTypical runningHoursPer day
Laptop60 W8480 Wh
Wi-Fi router and modem20 W24480 Wh
LED lights (5 bulbs)45 W5225 Wh
Phone charging (4 phones)20 W360 Wh
Totalabout 1,245 Wh

Typical values; a plug-in watt meter gives your real figure. Switching the router off outside work hours saves a lot.

Worked example

With 85% of rated capacity usable:

Battery ratingUsableThis setup lasts
500 Wh425 Whabout 8 hours
1,000 Wh850 Whabout 16 hours
2,000 Wh1,700 Whabout 33 hours

A desktop PC with a monitor (about 250 W typical, 2,000 Wh over 8 hours) uses far more than a laptop: with it, a 2,000 Wh battery covers roughly one workday. Surge is not an issue for these loads, so output rating rarely limits you.

Good to know

Open the calculator with a work-from-home setup filled in

Appliance figures are typical values, not measurements of your device: the label or a plug-in watt meter on yours wins. The sums assume 85% of a battery's rated capacity reaches your outlets (how the numbers work). We list no prices and have not hands-on tested any product.

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Check how long a specific model runs your setup (runtime tool).