Here’s a simple way to figure out how much power your solar panels can really produce. Use this calculator to figure out what size MPPT charge controller you need and test solar panel configurations to find the optimal setup for your RV, camper, tiny home, workshop, or off-grid cabin.
Calculate the output of up to ten solar panels using a variety of wiring setups, including:
- Matched panels with the same voltage and current ratings
- Mismatched panels with different specs
- Series, parallel, or mixed wiring configurations
- Systems built around 12V, 24V, or 48V battery banks
Here is how it works. Just enter the solar panel details for each group of solar panels (wired in series or parallel). The power output and recommended MPPT Solar Charge Controller will be calculated for you. Give it a try!
TIP: If your configuration has multiple groups of solar panels wired in series, parallel or series-parallel. Process each group separately.
Tell Me About Your Solar Panels
You will need to know the Voc and Imp ratings from your solar panels to get an accurate result. There should be a sticker on the back of the solar panel that shows the Voc and Imp ratings.
Find an MPPT Solar Charge Controller with these specs.
The controller voltage and current ratings should be higher than Calculated Input Voltage and Output Current shown above.
Victron controllers have the input voltage and output current rating in the name. Example: a Victron Smart MPPT 100 | 50 controller has an input voltage of 100V and an Output Current of 50A.
See our terms of use for details.
How the Solar Output and MPPT Ratings are Calculated
Estimated Solar Output
Series Configurations: Solar panel max voltage (Voc) ratings are added together. The current (Imp) rating is set to the lowest Imp rating in the group.
Parallel Configurations: The lowest voltage (Voc) rating of the group is used. Current (Imp) ratings are added together.
Solar Charge Controller Sizing
MPPT solar charge controllers are rated by Input Voltage (Volts) and Output Current (in Amps). However, there are many factors that will cause your solar panels to perform above or below their rated output. To account for this, it is common to size-up your MPPT controller.
EXAMPLE: Temperature, distance from the equator and air mass will impact solar panel performance above or below their ratings. You may exceed the rated output of your solar panels in colder regions and fall short in hotter regions.
This is the purpose of the Safety Margin option on the MPPT recommendation. When enabled, it adds 20 percent to the recommended current rating.
FREE Guide To RV Solar – What You Should Know Before Installing Solar
Are you considering solar? This guide has answers the most common questions and misconceptions about installing solar and camping off-grid in your RV, Van or Camper.