Solar + Battery Sizing Tool
Enter your essential loads and get a battery and solar size for true backup autonomy.
Your critical loads
Toggle what must stay on, and tune watts × hours/day.
300 Wh
360 Wh
240 Wh
960 Wh
400 Wh
400 Wh
Daily energy need
2,260 Wh
2.3 kWh/day
Battery (usable)
4.5 kWh
2-day reserve
Battery (buy this)
5.0 kWh
LFP, with losses
Solar array
628 W
~2 × 400W panels
A planning estimate using LFP chemistry and ~25% system losses. Real installs depend on climate, shading, inverter choice and local code — confirm with a qualified installer before buying. Reduce loads (LEDs, efficient fridge) to shrink everything.