How to Calculate Battery Bank
What is Battery Bank?
Battery Bank Size Calculator helps contractors and tradespeople accurately size, spec, and estimate materials and systems.
Formula
Battery kWh = Daily Usage × Autonomy Days / Depth of Discharge
Step-by-Step Guide
- 1Enter daily load, desired backup days, and max DoD
- 2Apply the formula using your project measurements
- 3Add required safety factors or waste allowances per code
Worked Examples
Input
5 kWh/day, 2 days, 50% DoD
Result
Battery = 5 × 2 / 0.50 = 20 kWh bank
Common Mistakes to Avoid
- ✕Not applying code-required safety factors or derating
- ✕Forgetting to account for waste and cut losses in material estimates
Ready to calculate? Try the free Battery Bank Calculator
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