Planning Tool

Battery Sizing

Estimate the battery storage your project might need based on daily electricity use, desired autonomy, and a usable-capacity assumption.

How the estimate works

The planner estimates usable battery storage from daily electricity use and the selected number of autonomy days. Nominal battery capacity is then estimated from the portion of capacity intended for use.

1–3 daysBattery autonomy

80%Default usable battery capacity

kWhStorage capacity unit

Important: This planner is an early-stage estimate, not a battery-system design, engineering recommendation, or equipment quote. The model does not account for detailed hourly load profiles, battery chemistry, temperature effects, inverter efficiency, charging limits, reserve requirements, cycle-life targets, electrical-code requirements, or specific equipment.

Why usable and nominal capacity differ

A battery's nominal capacity is not necessarily the amount you intend to use. This planner separates usable storage from nominal capacity so the planning assumption is visible rather than hidden in the calculation.

Based on this estimate

Recommended products to research

These are planning candidates based on the calculator result, not definitive equipment recommendations.

48V rack-style system

EG4 LifePower4 48V 100Ah

A 48V-class LiFePO4 battery option for larger stationary battery banks and rack-style expansion.

Nominal voltage: 51.2V
Capacity: 100Ah
Nominal energy: 5.12kWh
Chemistry: LiFePO4

Best for: Larger stationary battery systems where a 48V-class architecture fits the project.

View manufacturer specifications

5 units≈ 25.6 kWh nominal capacityCloser capacity fit

Portable power station

EcoFlow DELTA 2 Max

An integrated portable power station with LFP storage for projects where portability is a priority.

Capacity: 2,048Wh
AC output: 2,400W
Chemistry: LFP
Expansion: Up to two compatible extra batteries

Best for: Portable or flexible small-space power applications where an integrated power station makes sense.

View manufacturer specifications

13 units≈ 26.6 kWh nominal capacityCloser capacity fit

Compatibility reminder: Capacity fit alone does not establish compatibility. Verify system voltage, inverter and charger compatibility, continuous and peak power capability, battery configuration limits, temperature requirements, installation conditions, warranty terms, and current manufacturer documentation before choosing equipment.