1. What is UPS Battery Sizing?

UPS battery sizing determines the appropriate battery capacity (in ampere-hours) needed to power your solar system load for a specified autonomy period at a given voltage.

2. How Does the Calculator Work?

The calculator uses the battery sizing formula:

Where:

• Solar Load — Total power consumption of your system in watts
• Autonomy — Desired backup time in hours
• Voltage — System voltage (typically 12V, 24V, or 48V)

Explanation: The formula calculates the battery capacity needed to sustain your load for the specified duration at the system voltage.

3. Importance of Proper Battery Sizing

Details: Correct battery sizing ensures your solar system can meet power demands during periods without sunlight, prevents over-discharge, and extends battery life.

4. Using the Calculator

Tips: Enter your total solar load in watts, desired autonomy hours, and system voltage. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is autonomy in battery sizing?
A: Autonomy refers to how many hours you want your system to run on battery power without solar input.

Q2: Should I add a safety margin to the calculated size?
A: Yes, it's recommended to add 20-30% to account for inefficiencies and battery aging.

Q3: What's the difference between Ah and Wh?
A: Amp-hours (Ah) measure charge capacity, while watt-hours (Wh) measure energy capacity. Wh = Ah × V.

Q4: How does depth of discharge affect battery sizing?
A: If you only discharge to 50% DoD, you'll need twice the calculated Ah capacity.

Q5: What battery types can this calculator be used for?
A: It works for lead-acid, AGM, gel, and lithium batteries, though each type has different characteristics.