Free Solar Tool
Solar Panel Size Calculator
Find out how many watts of solar panels you need for home, RV, cabin or off-grid setup.
Select a setup or enter your own daily electricity usage below.
Enter daily power usage in kWh. Example: 300 units/month ≈ 10 kWh/day.
Most places get around 4–6 peak sun hours per day.
This includes inverter loss, wiring loss, dust and battery charging loss.
Recommended Solar Panel Size
0 WattsFill the details above to calculate your solar panel requirement.
Solar Panel Size Calculator
This Solar Panel Size Calculator helps you estimate how many watts of solar panels you need for your home, RV, cabin, camper van or off-grid solar power system.
How To Use This Solar Calculator?
First select your setup, then enter your daily electricity usage in kWh. After that, enter average sunlight hours and choose system loss. The calculator will show your estimated solar panel wattage.
Example Calculation
If your electricity usage is 10 kWh per day and your location gets 5 peak sun hours, then you may need around 2500 watts of solar panels after including system loss.
| Input | What To Enter |
|---|---|
| Daily Electricity Usage | Your daily power use in kWh |
| Sunlight Hours | Average peak sun hours per day |
| System Loss | Loss from inverter, wire, dust and battery |