1. What is the Battery Backup Size Calculation?

The Battery Backup Size calculation determines the required energy storage capacity (in kWh) needed to power a specific electrical load for a certain duration, accounting for inverter efficiency.

2. How Does the Calculator Work?

The calculator uses the equation:

Where:

• \( Load \) — Power consumption of the connected equipment (kilowatts)
• \( Time \) — Desired backup duration (hours)
• \( Inverter Factor \) — Efficiency factor (typically 1.1-1.2)

Explanation: The equation accounts for the total energy requirement and adjusts for typical inverter losses in converting DC battery power to AC power.

3. Importance of Battery Sizing

Details: Proper battery sizing is crucial for ensuring adequate backup power during outages, preventing premature battery failure, and optimizing system cost.

4. Using the Calculator

Tips: Enter load in kilowatts, desired backup time in hours, and inverter factor (default 1.1). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical inverter factor?
A: Most inverters have an efficiency of 85-90%, so the factor typically ranges from 1.1 to 1.2 to account for conversion losses.

Q2: How do I convert amps to kilowatts?
A: For AC systems: kW = (Amps × Volts × PF) / 1000, where PF is power factor (typically 0.8-1.0).

Q3: Should I add a safety margin?
A: Yes, it's recommended to add 10-20% additional capacity to account for battery aging and unexpected load increases.

Q4: How does temperature affect battery size?
A: Cold temperatures reduce battery capacity. In cold climates, you may need 20-30% more capacity than calculated.

Q5: Can this be used for solar systems?
A: Yes, but solar systems require additional calculations for days of autonomy and solar charging capability.