Technology

Solar Battery Sizing Calculator

Battery bank size for days of autonomy.

Enter your values

Results update instantly as you type — no submit needed.

Results
Battery bank size
23.61 kWh
Amp hours at system voltage
492
Usable energy
18.89 kWh
Cost estimate at $400/kWh
$9,444.44

Quick answer

Battery bank size must cover daily load across your autonomy days without exceeding depth of discharge.

Capacity = load × days ÷ (DoD × efficiency)

How to use the Solar Battery Sizing Calculator

  1. 1Enter your daily energy consumption.
  2. 2Choose days of autonomy without sun.
  3. 3Set depth of discharge for your battery chemistry.

Frequently asked questions

What DoD for lithium?

80–90% is safe for LiFePO4; lead acid should stay near 50%.

How many autonomy days?

Two is typical; three for remote sites.