Battery Run Time Calculator
Off-grid cabin power planning, RV camping, UPS backup runtime. Calculates hours and minutes a battery bank will power an AC/DC load based on battery chemistry DoD (LiFePO4 80-90%, AGM 50%) and inverter conversion loss.
Step-by-Step Derivation ▼ Show Steps
Calculations adhere to standard electrical equations and National Electrical Code guidelines.
Engineering Principles & Calculations
This calculator uses the exact mathematical relationships between Capacity (Ah), Voltage (12/24/48V), Load (Watts), Chemistry (Lead-Acid / Lithium), Inverter Efficiency (default 90%) to determine Runtime (Hours & Minutes), Total Usable Energy (Wh). In practical applications, electrical systems must account for safety derating factors, nominal vs actual voltages, and conductor resistance losses.
Calculates hours and minutes a battery bank will power an AC/DC load based on battery chemistry DoD (LiFePO4 80-90%, AGM 50%) and inverter conversion loss.
Typical Application & Best Practices
Off-grid cabin power planning, RV camping, UPS backup runtime.
Battery Run Time Calculator Benchmark Lookup Table
| Battery Bank | Load Watts | Usable Wh (80%) | Estimated Runtime |
|---|---|---|---|
| 12V 100Ah (1.2 kWh) | 50 W (Laptop + Lights) | 864 Wh | 17.3 Hours |
| 12V 100Ah (1.2 kWh) | 150 W (TV + Refrigerator) | 864 Wh | 5.8 Hours |
| 12V 100Ah (1.2 kWh) | 500 W (Microwave / Tools) | 864 Wh | 1.7 Hours |
| 12V 200Ah (2.4 kWh) | 150 W (Fridge + Starlink) | 1,728 Wh | 11.5 Hours |
| 24V 200Ah (4.8 kWh) | 500 W (Base Load) | 3,456 Wh | 6.9 Hours |
| 48V 100Ah (4.8 kWh) | 1,000 W (High Load) | 3,456 Wh | 3.5 Hours |