How To Connect RV Batteries to Solar Panels

Solar panels are a remarkable development in renewable energy! As an RVer, a solar panel system frees you! It allows you to go anywhere and stay anywhere, harnessing the incredible power of the sun to address all of your electrical needs.

How to connect solar panels to your RV batteries may be confusing for you, in today’s article,let’s figure it out!

Solar electric systems for RV’s vary enormously, especially if installing a larger system, make sure you are confident working with electrical wiring before taking this on. For systems up to a few hundred watts or kits, the voltages are not dangerous and can be installed by anyone. Regardless of the size, the following instructions are a high level of how the components should be wired.

Let’s assume that you’ve purchased a kit containing the solar panel system parts, and you have a battery or battery bank installed in your RV.

Your kit will contain:

1. A solar panel (or more than one, depending on what you’ve opted to buy).
2. A charge controller.
3. A wiring harness (and possibly connectors, adapters, and mounting brackets)

Steps for Connecting RV Solar Panels to Your RV Batteries

Here are the steps to connecting your solar panels to your batteries:

1. Mount your solar panels on the roof of your RV.

2. Mount your charge controller inside the RV as close to your batteries as possible.

3. Run your wiring from the solar panels into the RV and over to the charge controller. (You can run your wiring through a refrigerator vent or through the holes where the plumbing enters the RV if these are located near your batteries. If not, you can drill a hole through the roof of your RV to run your wires and thoroughly cover and caulk any drilled holes.) You should install a fuse or circuit breaker on the wires for this run.

4. Connect the wires from your charge controller to your battery bank. A fuse slightly larger than the charge controller’s rated current should be installed on these wires.

5. At this point, the system is fully installed but the RV solar panels are not connected to the charge controller. Before making the final connection it’s important to double-check all wiring to make sure polarity (positive and negative) are all correct. Once confident you can plug in the solar panels to the charge controller. We recommend doing this at night or with the solar panels covered by a blanket to prevent a spark.

6. This step is optional, but if you want to use 120-Volt AC appliances, you’ll want to mount an inverter inside your RV, as close to the batteries as possible, and run appropriate wiring to that inverter.

Do You Need To Use RV-specific Solar Panels?  

No! Any type of solar panel can be made to work with an RV; however, there may be some challenges.  

First is space available. An RV roof may have lots of stuff on it and require the use of smaller panels. If the roof is wide open, full-size residential panels like used on homes can be used for RV solar panels.

The second challenge with non-RV-specific panels is the voltage they operate at. Most RV solar panels are around 17-20 volts which will work with most PWM charge controllers to charge a 12-volt system. Home solar panels are usually 40-70 volts and cannot be used with PWM charge controllers.

You can use MPPT style controllers as long as they have a high enough voltage rating. Using an MPPT controller allows the use of most of any solar panel for an RV.

Are RV Solar Panels Worth It?

If you always camp at campgrounds and RV resorts where you will be paying for electrical hookups to power your RV and your various devices and appliances, then investing in a solar system may not be worthwhile.

If you want to camp in places like this without listening to your generator solar panels might be worth it!

However, if you like to boondock – to stay in areas where there are no electrical hookups – beaches, city parks, state parks, the desert, a solar panel system is an excellent addition to your RV lifestyle. Solar panels provide silent power and can minimize the need for a noisy generator to recharge your batteries.