Battery Bank Size Calculator

Calculate the optimal battery bank size for your solar power system based on your daily energy consumption, desired backup duration, and battery specifications.

Your average daily electricity consumption
Number of days you want to run without solar input
System voltage (common: 12V, 24V, 48V)
Maximum recommended discharge depth (typically 50% for lead-acid, 80% for lithium)
Typical inverter efficiency is 92-96%
Capacity loss due to temperature (5-20%)

How to Use This Calculator

  1. Daily Usage: Enter your average daily energy consumption in kilowatt-hours (kWh).
  2. Backup Days: Specify how many days of backup power you need.
  3. Battery Voltage: Select your system voltage (higher voltage means fewer parallel batteries).
  4. Depth of Discharge: Set the maximum discharge level for your batteries.
  5. Inverter Efficiency: Account for power losses in the inverter.
  6. Temperature Effect: Consider capacity loss due to temperature.

Understanding the Results

  • Required Battery Capacity: Total capacity needed in amp-hours (Ah).
  • Energy Storage: Total energy storage capacity in kilowatt-hours (kWh).
  • Minimum Battery Count: Suggested number of batteries based on typical battery sizes.

Note: This calculator provides estimates based on typical conditions. Consider these factors:

  • Battery type (lithium vs. lead-acid)
  • Temperature variations
  • Future energy needs
  • Budget constraints
  • Available space

For precise sizing, consult with a solar installation professional.