Flagship Tool
Solar Generator Size Calculator
System-level off-grid capacity: build your daily appliance list and get battery capacity, inverter peak, solar array size and charge time. Includes a ready-to-load 30A RV example.
1 · Your daily appliance list
Power × hours per day. Core figures calibrated to official labels; generic devices illustrative.
| Appliance | Watts | h/day | Wh/day | |
|---|---|---|---|---|
| Daily total | 1,506 Wh | |||
Load 30A RV example (AC + fridge + pump + lights + CPAP)
2 · Off-grid parameters
3 · System size results
Battery capacity
1,772 Wh
daily Wh × autonomy ÷ 0.85
Inverter peak
130 W
max(largest appliance × 1.25, actual surge)
Solar array
418 W
daily Wh ÷ sun hours ÷ efficiency
Solar charge time
5.3 h
battery ÷ array output
Scope boundary: this tool computes system-level capacity only — battery,
inverter, array, charge time. It does not include kit price lists or brand price comparisons. For
station-level runtime estimates use the Runtime Calculator.
Calculation rules
| Component | Formula | Example (30A RV, loaded) |
|---|---|---|
| Daily draw | Σ (watts × hours) | 18,342 Wh |
| Battery | daily Wh × autonomy ÷ 0.85 usable | 18,342 ÷ 0.85 ≈ 21.6 kWh |
| Inverter peak | max(appliance W × 1.25, actual surge) | max(1500 × 1.25, 3000) ≈ 3.0 kW |
| Array | daily Wh ÷ sun hours ÷ efficiency | 18,342 ÷ 4.5 ÷ 0.8 ≈ 5.1 kW |
Related
Core device figures calibrated (CPAP/fridge/RV AC); generic devices remain typical/illustrative.
Assumptions shown per component. Version v0.2.0 · updated 2026-08-09.