How To Hook Up Solar Panels To RV Batteries?

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A free and plentiful source of energy is the sun.

It can run houses, businesses, etc. even your RV may be powered by it!

Without a generator and in locations where shore power is not an option, you may use this practical energy source to charge your RV batteries and operate your electrical equipment (think boondocking).

And it’s more simple than you would have imagined to install solar panels to your recreational vehicle.

Using the instructions in this step-by-step tutorial, you can charge your RV batteries wherever your next journey takes you by connecting solar panels to them.

How much of a Solar Panel do I need to Charge my RV Battery with?

Let’s quickly assess the size of the solar panel(s) you’ll need to charge your batteries and power the accessories and appliances in your RV before moving on to how to connect solar panels to your RV batteries.

I try to keep things as straightforward as I can.

If there is straight sunshine, a 200 to 400 watt solar panel configuration will often be sufficient to charge your RV batteries.

A 200-watt system should be enough for basic power requirements, such as lighting, fans, electronics in propane appliances, phone chargers, etc.

Adding a television, microwave, and other high-power electrical devices will probably need closer to 400 watts of electricity (or more).

There are several solar calculators available online to assist you in determining your solar wattage needs, but since there are so many factors at play, they are at best educated estimates.

In essence, the calculators attempt to balance the power output of your solar cells with the electric power needs of your recreational vehicle.

However, testing your system in the real world is the only reliable method to know.

And if you’ve set up your solar power system correctly (which we walk you through step-by-step below), you’ll be able to rapidly add more solar panels to it if necessary.

5 Fundamental Parts of an RV Solar Power System

#1. Solar Panels

The photovoltaic cells that make up solar panels are capable of capturing photons, which are very small particles of light.

Since they are photovoltaic, they produce power from sunshine.

A solar panel is made up of several connected cells.

You must determine how many solar panels you’ll need.

Simple calculations may be used to do this.

#2. A Charge Controller

Your batteries’ lifetime will be shortened or shortened if you overcharge them.

A charge controller prevents the battery from being overcharged by the solar panel.

It controls the battery’s voltage and current as they go from the solar panels.

#3. An Inverter

Your battery’s 12-volt DC electricity is converted by the inverter into 120-volt AC power, which may be used to run devices like your microwave, coffee machine, or TV.

Without an inverter, you may still have a solar power system, but it would only be able to power 12-volt DC equipment like your lights, water pump, fan, and furnace.

#4. A Transfer Switch

Sometimes the transfer switch is included within the inverter, but they may also be purchased separately.

A transfer switch automatically alternates between two incoming sources of AC power while providing electricity to the RV electrical panel.

Therefore, electricity is provided by either the inverter or shore power, but not both at the same time.

If both sources were allowed at once, the electrical system would be harmed.

#5. Battery

Solar power generated by the panels is stored in the battery so you may access it anytime you choose.

AGM Lead Acid, Flooded Cell Lead Acid, and LifePO Lithium are the three different kinds of batteries.

Determine the wattage of each device you’ll be using and how long you’ll be using it to determine how many batteries you’ll need.

Then divide that result by the amount of days you will be without electricity.

To get a basic calculator, click here.

How To Hook Up Solar Panels To RV Batteries?

How to Connect a Solar Panel to a Battery and Inverter Diagram
How to Connect a Solar Panel to a Battery and Inverter Diagram

It is simple to connect your RV batteries to your solar panels.

In layman’s terms, cables transfer solar energy from your RV’s solar panels to the charge controller inside, and then the charge controller is connected to your RV’s batteries to charge them.

It’s that easy.

Total Time: 15 minutes

Step: 1

Utilizing the tray cable, connect the battery to the charge controller. The charge controller’s red wire should go into the positive port and the green wire should go into the negative port. Connector screws should be tightened. then connect the battery to the tray cable’s other end (red connects to the positive terminal, green to the negative). Important: Make sure to complete this step first to prevent causing permanent harm to the solar system’s components!

Step: 2

Connect the MC4 male connection of the adapter kit to the MC4 female connector of the solar panels. After that, join the MC4 male connection on the solar panel to the MC4 female connector on the adapter kit.

Step: 3

Connect the negative solar panel wire to the charge controller’s negative solar terminal. After that, connect the positive solar panel line to the charge controller’s positive solar terminal. To connect the wires to the charging controller, you may need to strip the ends of the cables 3/8′′. To guarantee a secure connection, tighten the charge controller’s screws.

Step: 4

Optional: After ensuring that everything is connected correctly, attach the negative battery terminal to the power inverter’s negative port before connecting the inverter. After that, connect the positive battery terminal to the power inverter’s positive port.


  • At least 200 watts of solar panel(s) (you can wire multiple 100w solar panels in parallel)
  • Solar charge regulator
  • Kit for 10 AWG Solar Panel Connectors
  • 10 AWG Cable Tray
  • 12 volt battery (If required.
  • This Renogy deep-cycle, 100 amp-hour battery is great.)
  • A mounting bracket is optional.
  • Elective: Inverter (DC to AC power inverter to power your 120 volt AC appliances)

Materials: To get your solar charging system up and running, we strongly advise buying the Renogy Complete RV Solar System Kit, which includes everything you need (apart from the RV battery and optional inverter). One of the best off-grid RV solar systems available today was created by Renogy. Tip: You’ll need a high-quality battery if you want to get the most out of your solar energy system. To get the finest battery for you and your camping requirements, check out our selections for the best RV battery for boondocking.

Do you learn best visually? For a step-by-step explanation of how to connect solar panels to your RV batteries, watch this video.

Important: Make sure you read and abide by the installation instructions and specifications included with your individual solar panel kit.

These may vary from kit to kit.

Where you want to install your RV solar panels is one more thing to think about.

You may choose from many options:

  • RV Roof-mounted: With the help of the optional mounting kit, you can put your solar panels on the roof of your camper, travel trailer, or RV.You’ll then need to utilize a cable entrance plate to run the cables inside the vehicle.
  • Manual setup: When you wish to utilize your solar panels, you may also physically put them up and connect them outdoors.When not in use, pack them up and store them. If you want to take this route, keep in mind that the charge controller must be located inside your RV, away from the elements. If feasible, one alternative is to place the charge controller adjacent to your RV batteries in a storage area that is simple to reach.

You just need to do that to connect your portable solar energy system! And don’t forget, one of the finest solar panel systems for charging RV batteries that we’ve used is the Renogy RV Solar Panel Kit, which will make the DIY process much simpler.

Can I Directly Connect a Solar Panel to a Battery?

If the solar panel has a very low power (5 watts or less), connecting it straight to a battery (or bank of batteries) could work, but it’s not advised.

For optimum performance and battery longevity, you should securely charge your camper batteries using a battery charge controller.

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Ryan is a RV product expert with nearly a decade of experience researching, developing, and testing RV products.

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