Tick the appliances you'd actually need during an outage, set how long it might last, and get an honest answer in watt-hours — including inverter losses and headroom, with the math shown.
| Appliance | Qty | Hours in use |
|---|
Wattages are typical modern values (fridges and freezers use their average cycling draw for energy, and full compressor draw for the inverter check). Check your appliance labels for exact numbers.
Battery power stations are sold by rated watt-hours, but you never get all of them. Converting DC battery power to AC wall power loses roughly 15%, so we divide your energy need by 0.85. We then add 20% headroom — batteries degrade with age, cold weather cuts capacity, and outages run longer than forecast.
Energy (watt-hours) decides how long you can run things: Wh = watts × hours, summed over your appliances. Power (watts) decides what you can run at once: the station's continuous output must exceed the total draw of everything running simultaneously, and its surge rating must handle the biggest motor start-up (fridge and freezer compressors briefly pull 5–6× their running draw).
Fridges and freezers cycle on and off, so their average energy draw (used for the Wh math) is far below the compressor's running draw (used for the output check). That's why a "150W" fridge only needs about 1.4 kWh per day, not 3.6 kWh.