Battery Storage Calculator Interactive Calculator
Size a battery storage system for any application — backup power, load shifting, or grid services.
By the analysts at Blackridge Research
Inputs
Results
What this means
Adjust the inputs to calculate.
About the Battery Storage Calculator
Battery storage sizing determines the capacity needed for your application.
Size depends on load, autonomy days, and battery technology.
This calculator determines the required battery capacity for any application.
Formula
Battery Size = Daily Load × Days of Autonomy / Depth of Discharge - BS
- — Battery Size (kWh)
- L
- — Daily Load (kWh)
- DA
- — Days of Autonomy
- DoD
- — Depth of Discharge
Battery Size = Daily Load × Days of Autonomy / Depth of Discharge.
Depth of Discharge is typically 80% for lithium-ion batteries.
How to use this calculator
- 1
Enter daily load
Daily energy consumption in kWh.
- 2
Enter autonomy days
Number of days of backup power needed.
Example calculations
Residential battery backup
Example 1A home uses 20 kWh/day and needs 2 days of backup power.
- Battery size:
- 50.0 kWh
- Recommendation:
- 50 kWh lithium-ion system
Interpreting your results
Battery sizing should account for depth of discharge, efficiency, and degradation.
Lithium-ion batteries are the standard for most applications.
Lead-acid batteries require larger sizes due to lower depth of discharge.
Need the market data behind this calculator?
The Battery Storage Calculator is only as good as its inputs. Blackridge Research publishes syndicated market reports with vetted market sizes, growth rates, and competitive landscapes across 40+ industries — and builds custom studies when the shelf report doesn't exist.
Industry applications
Business
- Energy storage planning: size battery systems.
- Investment decisions: assess storage viability.
- Grid services: plan battery capacity for grid applications.
Construction
- Building systems: size battery backup for buildings.
- Off-grid projects: determine storage requirements.
Research
- Energy analysis: evaluate storage economics.
- Feasibility studies: assess storage viability.
Common mistakes to avoid
-
Ignoring depth of discharge
Different battery chemistries have different DoD limits.
-
Forgetting degradation
Battery capacity degrades over time. Size up accordingly.
Frequently asked questions
What is a good battery depth of discharge?
Lithium-ion: 80-100%. Lead-acid: 50%.
How long do batteries last?
Lithium-ion: 10-15 years. Lead-acid: 3-5 years.
Glossary
- Depth of discharge:
- The percentage of battery capacity used.
- Days of autonomy:
- The number of days the system can operate without recharging.
- Lithium-ion:
- The most common battery chemistry for energy storage.
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