Power Station Size Calculator
Pick what you want to run and for how long. We'll tell you the minimum battery size — and match it to real power stations.
Add a device
Your load
Phone charge
12W × 2h = 24Wh
Laptop
60W × 4h = 240Wh
Recommended power station
Minimum capacity
350Wh
Total load 264Wh + 15% buffer for inverter efficiency & battery reserve.
Peak output needed
60W
Highest single-device wattage. The station's AC output must exceed this number.
How this works
How do I calculate my watt-hour needs?
Add up (wattage × hours) for every device. Then add 15-20% for inverter inefficiency and battery reserve. A 100W laptop for 4 hours = 400Wh × 1.15 = 460Wh minimum.
What's the difference between battery capacity (Wh) and output (W)?
Watt-hours measures how much energy is stored (capacity). Watts measure how much power can be delivered at once (output). You need both: enough Wh for your runtime, enough W to power your biggest device.
Should I size up for emergencies?
Yes. Real outages last longer than expected, and solar recharge slows in cloudy weather. For emergency backup, double your daily calculated Wh.
Can a power station run a fridge or coffee maker?
Fridges yes, easily — they cycle on/off and average ~50-100W. Coffee makers and microwaves draw 1000-1500W in short bursts, which exceeds smaller stations' output. Check the AC output spec against your peak device wattage.