Solar Panel, Inverter, Battery Calculator

This tool will help you to precisely calculate the required solar panel wattage, inverter capacity, and battery size based on the power consumption and the backup time.

Assumptions used in the Calculator:

Solar Panel Calculation:

Solar Panel wattage or power is dependent on the total daily energy consumption of the house.

Here we Assume 5 peak sun hours per day (standard for many regions).

Inverter Calculation:

Inverter wattage or power should be 20% higher than the total load to account for the efficiency losses.

Battery Calculation:

Here we use a 12V system (common for most of the small-scale solar setups).

Here we assume 80% Depth of Discharge (DOD) for lead-acid batteries.

And we assume 90% as the inverter efficiency.

How to Use the Calculator

Enter Load Power (Watts): This is the total power consumption of the appliances you want to run.

Enter Backup Time (Hours): This is how many hours you want the system to provide the power.

Click "Calculate" to get:

Solar Panel Wattage Required (based on 5 peak sun hours).

Inverter Size (20% higher than total load).

Battery Capacity in Ah (12V system, 80% DOD, 90% inverter efficiency).

Example Calculation

Suppose if we have:

Load Power = 500W

Backup Time = 5 Hours

Solar Panel Calculation:

Daily Energy Required = 500W × 5h = 2500 Wh

Solar Panel Required = 2500Wh / 5h = 500W panel

Inverter Calculation:

Inverter Size = 500W × 1.2 = 600W

Battery Calculation:

Required Battery Capacity = (2500Wh / 12V) / (0.8 × 0.9)

Required Battery Capacity = 231 Ah (12V)

So the results will show as:

• Solar Panel: 500W
• Inverter: 600W
• Battery: 231Ah (12V)