1. What is Backup Capacity?

Backup capacity refers to the amount of energy storage (in amp-hours) needed to power your RV for a specified number of days without solar input. It helps determine the appropriate battery bank size for your solar power system.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• RV Daily Consumption — Total energy used per day in watt-hours
• Solar Voltage — System voltage (typically 12V, 24V, or 48V)
• Autonomy Days — Number of days you want backup power for

Explanation: The equation converts your daily energy consumption from watt-hours to amp-hours at your system voltage, then multiplies by the number of days you want to be covered.

3. Importance of Backup Capacity

Details: Properly sizing your battery bank ensures you have enough power during periods of low sunlight or increased energy demand. Undersizing leads to power shortages while oversizing increases cost and weight unnecessarily.

4. Using the Calculator

Tips:

• Measure or estimate your daily energy consumption accurately
• Use your actual system voltage (12V, 24V, etc.)
• Choose autonomy days based on your typical weather patterns and usage needs (3-5 days is common)

5. Frequently Asked Questions (FAQ)

Q1: How do I determine my RV's daily consumption?
A: Add up the watt-hours used by all appliances over 24 hours, or use a power monitor to measure actual usage.

Q2: What's a typical autonomy period?
A: Most systems are designed for 3-5 days of autonomy to account for cloudy weather.

Q3: Should I add a safety margin?
A: Yes, it's recommended to add 20-30% to the calculated capacity to account for battery aging and efficiency losses.

Q4: Does temperature affect battery capacity?
A: Yes, cold temperatures reduce battery capacity. In cold climates, you may need 20-50% more capacity.

Q5: What about battery depth of discharge?
A: This calculation assumes 100% discharge, but you should limit discharge to 50% for lead-acid or 80% for lithium to prolong battery life.