Battery Bank Wattage Calculator

Calculate total and usable watt-hours for your battery system

Battery Bank Wattage Calculator

For Solar, RV, and Off-Grid Systems

Results:

Total Watt-hours (Wh): 0.00

Usable Watt-hours (Wh): 0.00

How to Use the Battery Bank Wattage Calculator

Basic Calculation

  1. Enter Battery Voltage (V)
  2. Enter Battery Capacity (Ah)
  3. Default DoD and Inverter Efficiency will be used

With Depth of Discharge

  1. Enter Voltage and Capacity
  2. Adjust Depth of Discharge (DoD %)
  3. This impacts usable capacity

With Inverter Efficiency

  1. Enter Voltage, Capacity, and DoD
  2. Adjust Inverter Efficiency (%)
  3. Accounts for energy loss during conversion

Battery Bank Fundamentals

Battery Capacity & Voltage

Battery capacity (Ah) and voltage (V) determine the total energy stored. Watt-hours (Wh) is the standard unit for energy.

Depth of Discharge & Efficiency

  • Depth of Discharge (DoD): The percentage of battery capacity that has been discharged. Exceeding recommended DoD can shorten battery life.
  • Inverter Efficiency: The efficiency of converting DC battery power to AC power for appliances. Energy is lost during this conversion.

Key Formulas:

Total Watt-hours (Wh) = Battery Voltage (V) × Battery Capacity (Ah)

Usable Watt-hours (Wh) = Total Watt-hours (Wh) × (DoD / 100) × (Inverter Efficiency / 100)

Calculation Formulas

Total Watt-hours (Wh):
Wh_total = V × Ah

Usable Watt-hours (Wh):
Wh_usable = Wh_total × (DoD / 100) × (Efficiency / 100)

Example Calculation

For a 12V, 100Ah battery with 80% DoD and 90% Inverter Efficiency:

Battery Voltage: 12V

Battery Capacity: 100Ah

DoD: 80%

Inverter Efficiency: 90%

Total Wh = 12V × 100Ah = 1200 Wh

Usable Wh = 1200 Wh × (80 / 100) × (90 / 100) = 864 Wh

Total Wh = 1200.00 Wh | Usable Wh = 864.00 Wh

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