Battery capacity calculator
Tick appliances, tweak wattage and hours of use. The result is the minimum recommended Wh capacity with standard headroom.
Formularequired (Wh) = daily consumption × 1.2 / 0.8
Appliances per day
Fridge (compressor)Wh
LaptopWh
Phones (2x)Wh
LED lightsWh
TVWh
Router Wi-FiWh
CPAPWh
MicrowaveWh
Estimated daily consumption
1890 Wh
Required battery capacity
2900 Wh
Includes 80% DoD and 20% margin
Methodology and assumptions
Usable LiFePO4 capacity is roughly 80% of nameplate (DoD). We add a 20% margin for inverter losses and cloudier days: capacity = consumption × 1.2 / 0.8.
Do not forget surge loads — a fridge compressor briefly draws 3-4x its rated power. Check the station’s surge rating, not just capacity.
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