1. What is the Solar Panel to Battery Calculator?

This calculator helps determine the battery capacity needed to store energy generated by solar panels based on panel power, sunlight hours, and battery voltage.

2. How Does the Calculator Work?

The calculator uses the following formula:

Where:

• Solar Panel Power — Rated output of solar panel in watts
• Sun Hours — Average daily peak sunlight hours at your location
• Battery Voltage — Voltage of your battery bank (e.g., 12V, 24V)

Explanation: The formula calculates how many amp-hours your battery needs to store to match the solar panel's daily energy production.

3. Importance of Battery Capacity Calculation

Details: Proper battery sizing ensures you can store enough solar energy to meet your needs during periods without sunlight, preventing system failures and optimizing performance.

4. Using the Calculator

Tips: Enter solar panel wattage, average daily sun hours for your location, and battery bank voltage. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What are typical sun hour values?
A: Sun hours vary by location and season, typically ranging from 1-8 hours per day. Check solar insolation maps for your area.

Q2: Should I account for system losses?
A: Yes, multiply the result by 1.2-1.5 to account for typical system losses (inefficiencies in charging, wiring, etc.).

Q3: What battery voltage should I use?
A: Common voltages are 12V, 24V, or 48V. Higher voltages are more efficient for larger systems.

Q4: How does this relate to days of autonomy?
A: Multiply the result by the number of days you want backup power for (e.g., 3 days of autonomy = 3 × calculated Ah).

Q5: Can I use this for lithium batteries?
A: Yes, but lithium batteries can typically discharge deeper than lead-acid (80-100% vs 50%), so you may need less capacity.