Before you buy panels or a battery, you need one number: how much energy you use each day. Use the calculator below to total your appliances, then read the guides underneath for the details.
Appliance load calculator
| Appliance | Watts | Hours per day |
|---|
Estimate only: assumes 25% system losses and 80% usable lithium capacity. Add a safety margin of 10-20% if your usage varies.
How the sizing works
Daily energy
Watts multiplied by hours of use, added up for every appliance, gives watt-hours per day.
Solar panels
Daily watt-hours divided by your peak sun hours, then adjusted for losses in cables and the charge controller.
Battery
Daily watt-hours times your days of backup, divided by voltage and by the usable share of the battery.
Next step: compare kits and budget builds, learn wiring and installation, or choose batteries and inverters. New to the terms? Start with Solar Basics.