Let’s say you have a pre-installed solar kit on your RV, camper van, or any other home or vehicle and you’re looking to upgrade your system. Or say you already have panels on your cabin or tiny home and want to add more.
Whatever the reason, upgrading your solar system is something that you want to do. However, it’s not as easy as grabbing a panel with a higher wattage and adding it to your system.
Can You Mix and Match Panels?
Do you have a pre-existing system with a built-in 100W panel and want to use it with your newly purchased 250W panel, but you don’t know if you can?
Simply put: yes, you can mix and match solar panels with different wattages. Although it’s not recommended, it’s not prohibited and you can do so at your leisure.
Note: To get the maximum efficiency from your system and keep your 100W panel, you should get an additional controller for your new solar panels.
How to Mix Different Wattage Solar Panels
There are two wiring options when connecting panels with different wattages: series or parallel. Wiring in series means you connect the positive to the negative whereas wiring in parallel means you wire positives together and then wire the negatives together.
Wiring in Parallel
When mixing panels with different wattages but similar voltages, the best way to wire them would be in parallel. To calculate this, you add the amperage of the two panels and multiply that number by the lowest Max Voltage between the two panels to get the total watts.
For this example, let’s use the MEGA Series 250 panel coupled with the MEGA Series 100 panel.
Take a look at the example below:
It should be noted that you want the panels to have the same voltage. In this case, both the MEGA Series 100 and 250 each have 12V. If the voltage of the panels is different, only then would you want to wire in series.
Wiring in Series
It’s not recommended to wire mix matched panels in series. Doing so will cause the total wattage output to decrease, resulting in less power generated. This is because when wiring in series, you add the voltages together and multiply that by the lowest amperage for the equation, resulting in a lower wattage.
Using the same example, if we were to use the MEGA 100W and 250W panels, you would end up with far less wattage capabilities.
The only time it would be recommended to wire in series would be if your solar panels have different voltages such as a 12V and a 24V solar panel as it will give you the higher voltage option. The amperage won’t change; instead, the solar panels connected in series will choose the lowest amps between them.
It’s generally recommended that if you’re going to use solar panels with different wattages each panel with a unique wattage has its corresponding charge controller. If you’re looking to upgrade your solar system, make sure to get the same type of panel (watts, volts, etc.). Nevertheless, using different solar panels is doable and can still provide all the energy you need.
If you want to learn more about mixing different wattage solar panels, check out our video where Jacob goes further in-depth with how to do so and what to expect when you do.