1. What is the Battery Size Calculation?

The battery size calculation determines the required capacity (in ampere-hours) of a home battery system in Australia based on your energy consumption, desired days of autonomy, battery voltage, and depth of discharge.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• Australia Home Consumption — Your daily energy usage in watt-hours
• Autonomy Days — Number of days you want the battery to last without charging
• Battery Voltage — Voltage of your battery system (typically 12V, 24V, or 48V)
• Depth of Discharge — Fraction of battery capacity that can be used (typically 0.5-0.8)

3. Importance of Proper Battery Sizing

Details: Correct battery sizing ensures your home has enough power during outages or off-grid periods while avoiding unnecessary costs from oversizing.

4. Using the Calculator

Tips: Enter your average daily consumption in watt-hours, desired autonomy days, battery bank voltage, and recommended depth of discharge (usually 0.5-0.8 for lead-acid, 0.8-0.9 for lithium).

5. Frequently Asked Questions (FAQ)

Q1: How do I find my home's daily consumption?
A: Check your electricity bill for kWh usage and multiply by 1000 to get watt-hours, then divide by 30 for daily average.

Q2: What are typical autonomy days for Australian homes?
A: Most systems are designed for 1-3 days autonomy, depending on location and solar input.

Q3: What battery voltage should I choose?
A: 12V for small systems, 24V for medium, and 48V for larger home systems is common in Australia.

Q4: Why is depth of discharge important?
A: Deeper discharges reduce battery lifespan. Lead-acid batteries typically use 50% DoD, lithium can handle 80-90%.

Q5: Should I add a safety margin?
A: Yes, consider adding 10-20% to the calculated size to account for inefficiencies and future needs.