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Power station size calculator

Tick your devices and outage length to estimate the battery capacity you need.

Work out how big a portable power station you need for a blackout. Tick the devices you would run, adjust the watts and hours, set how many days you want to cover, and we estimate the battery capacity and show example models. Figures are estimates you can edit; confirm exact specs on the product page.

How this is estimated

We add up watt-hours per day for the devices you tick (watts times hours, with a duty cycle for the fridge), multiply by the number of days, and divide by an inverter efficiency of 85 percent to get the capacity you need. We then suggest the nearest capacity class and show one example model per brand. A single 100 W solar panel makes only a few hundred watt-hours on a good day, so it stretches a battery rather than replacing it. Kettles and rice cookers draw a lot; running them off a battery drains it fast, so treat those as occasional.

Estimates only. Real runtime depends on the exact device, temperature and the unit's usable capacity and inverter. Check the product page and consider a safety margin.