Solar Battery Storage Bank Sizing Tool

Daily Load

OFF

Usable Capacity

OFF

Rated Bank (kWh)

OFF

Bank Config

OFF

System Inputs

Enter your daily energy demand and system parameters. Adjust the DoD depending on battery chemistry.

Daily Energy Consumption — kWh/day Autonomy Days (reserve duration) System Voltage — V

Battery Chemistry

LiFePO4 80% max depth of discharge

Lead-Acid 50% max depth of discharge

Max Depth of Discharge (DoD) — % Inverter / System Efficiency — %

Bank Sizing Results

Required Usable Energy

—

kWh usable

Required Rated Capacity

—

kWh rated

Rated Amp-Hours

—

Ah @ bank voltage

Formula

—

calculation path

Number of Batteries & Series/Parallel Layout

Choose a battery model, then the tool computes how many are needed and how to wire them (series to build the system voltage, parallel to reach the required Ah).

Battery Voltage — V Battery Capacity — Ah Preset Packs

Serial Count (batteries in series/string) Parallel Strings

Serial count is pre-filled to build the system voltage (48 V ÷ 12 V = 4). Parallel strings are computed automatically from capacity; you can raise your battery Ah to reduce how many strings are needed.

Method & Quick Reference

Standard battery-bank sizing math for off-grid / solar systems.

Rated capacity (kWh) = (Daily kWh × Autonomy days) ÷ (DoD × Inverter efficiency)
Amp-hours (Ah) = Rated kWh × 1000 ÷ System voltage
Batteries per string = System voltage ÷ Battery voltage · Strings = ceil(Ah ÷ Battery Ah)

Lead-Acid DoD ≈ 50% · cheaper upfront, shorter cycle life, needs maintenance

LiFePO4 DoD ≈ 80% · higher upfront, longer life, built-in BMS, lighter

Inverter loss 90–96% typical; always derate to cover AC conversion losses