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Solar Sizing Calculator
Add your appliances to calculate how much solar and battery capacity you need for boondocking.
Step 1 — Your Appliances
Add each appliance, its wattage, and how many hours per day you run it.
| Appliance | Watts | Hrs/Day | Wh/Day |
|---|
Step 2 — Your Location
Peak sun hours vary by region. Desert Southwest gets the most.
Your Results
0
Wh/day needed
0W
Recommended solar
0 Ah
Battery bank (100Ah LiFePO4)
Add appliances above to see your recommendation.
How the Calculation Works
The calculator multiplies each appliance's wattage by its daily run time to get watt-hours per day (Wh/day). It then divides by your location's peak sun hours to determine how many solar watts you need, adding a 25% safety buffer for cloudy days and inefficiency losses.
For the battery bank, it assumes 2 days of autonomy (cloudy days with no solar input) and limits discharge to 80% for LiFePO4 batteries — the standard for long battery life.
Common Appliance Reference
| Appliance | Typical Watts |
|---|---|
| LED lighting (4 lights) | 20–40W |
| Laptop | 40–65W |
| Phone charging | 5–18W |
| 12V refrigerator | 30–60W avg |
| Electric blanket | 50–150W |
| CPAP (no heat) | 30–60W |
| Fan (12V) | 15–35W |
| Water pump | 40–60W (intermittent) |
| TV (32") | 50–80W |
| Inverter microwave | 900–1200W |