Solar + battery sizing from published data
SolarSized: How much solar and battery do I need?
How much solar and battery do I need?
Pick your state, tick appliances or enter your monthly kWh, and get panel watts, battery kWh and inverter size.
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LiFePO4 home batteries400 W solar panelsHybrid invertersPortable power stations
Popular scenarios
Popular answers
- How many solar panels to run a full-size refrigerator
- How many solar panels to run a mini fridge
- How many solar panels to run a chest freezer
- How many solar panels to run an 8,000 Btu window AC
- How many solar panels to run a 10,000 Btu window AC
- How many solar panels to run a CPAP
- Battery size for 3 days of essentials
Questions
How many solar panels do I need?
Divide daily watt-hours by (peak sun hours × 0.75). The 0.75 factor covers wiring, temperature, inverter and dust losses. Example: 10 kWh/day in Michigan (4.47 sun hours) needs about 2,983 W, or 8 × 400 W panels.
How big a battery do I need?
Daily watt-hours × days of backup ÷ (0.9 usable depth of discharge × 0.9 inverter efficiency).
Where do sun hours come from?
State annual averages of peak sun hours derived from NREL PVWatts v8 (NSRDB typical-year data).