Solar Panels

How to Install Solar Panels on a Caravan (Step-by-Step)

By:Michael Johns

fixing a solar panel to caravan

In this article, you’ll learn how to install solar panels on a caravan. 

Fitting solar panels to a caravan roof is a pretty simple process and is one that you can carry out yourself. The job can be completed in just a few hours and allows you to holiday with all the benefits that solar power brings.

You’ll only need a few tools to complete the job, plus if you decide to glue the brackets to your roof it requires no drilling. Below we will go through a step-by-step overview of installing caravan solar panels. This includes what you’ll need and in what order to connect the electronics. 

If you’re still looking to buy then read my guide to the Best Solar Panels for Caravans.

What You Need to Install Solar Panels on a Caravan

Let’s discuss what you’ll need to complete the job. Most of the equipment should arrive with your solar panels, especially if you order a starter kit. In addition, there are a couple of tools required too.

  • Solar Panels (duh…)
  • Solar Charge Controller
  • Leisure Battery
  • Corner Mounts – These are a mount designed to fit around your solar panel and glue to the roof. You can find two types. Some will fit over the corner like a hood while others attach to the panel frame with screws.
  • Sikaflex – This is an adhesive with plenty of strength and is recommended for use on RVs. You could also use 3M VHB double sided tape for flexible solar panels where adhesive is too messy.
  • Marker PenIsopropyl Alcohol (IPA) – To thoroughly clean your roof for the adhesive.
  • Drill and Screwdriver – You might need to add holes to your solar panels. And screw the mounts to the frame.

It’s likely that you’ll already have a few pieces of this installed in your caravan such as the deep cycle battery and power inverter.

Wiring Diagram – Where Everything Connects Together

Let’s start by looking at the wiring diagram to help you understand where the components connect together. 

Caravan solar panel diagram

There are 3 main components to your system – solar panel, charge controller, and batteries. When connecting everything, always connect the charge controller to the battery first. Then connect the solar panels to the charge controller.

Read Instructions and Specifications

You should take the time to fully read the instructions with your equipment. While most components work in a similar manner you should know the ins and outs of yours. This will help you understand everything further. In addition, the steps below are written as a guide, you should tailor your steps to your equipment where necessary.

How to Install Solar Panels on a Caravan

The six steps below take you through the installation and have you ready to power up all your gadgets and electronics.

You can also watch this video for an in-depth walkthrough:

The below steps discuss the way to glue solar panels to your roof. You can easily replace these steps by drilling holes and securing Z-bracket mounts instead.

1. Clean Roof

The most important part of the process is ensuring you have a clean roof with no grease, dirt, or dust. This is because we are going to glue and bond the solar panels to your caravan roof.

Don’t rely on a quick wipe or soapy water. You need to use a solvent to cut through grease residue. Alcohol dissolves grease and water will get rid of dirt and dust. 

Mix isopropyl alcohol and water (50:50). Using a fresh cloth thoroughly clean the area you plan to place the mounts.

Leave the surface dry thoroughly before applying the adhesive.

2. Attach Mounts to Solar Panels

While leaving the roof to dry you can securely fasten the mounts to the solar panels. This is because it’s tricky if not impossible to do if you try to glue the mounts to the roof first.

Fasten the mounts to the panels with the included screws. When using mounts from the manufacturer of the panel they should line up with predrilled holes.

If there are no predrilled holes, carefully drill them into the aluminium frame.

3. Mark Out Your Mounts

Place the solar panels with the mounts onto the caravan roof and mark out where the mounts go. This will enable you to apply adhesive in the correct place.

Use a pen to mark the edge of the exact spot where the mounts will be glued. Don’t mark where the adhesive will go as we want a clean dry surface.

Once marked, you can remove the equipment from the roof to continue preparation.

4. Glue Mounts and Panel in Place

With everything marked out you can now glue your mounts and panel in place. Read the usage instructions on your adhesive. It is ideal to work quickly in a warm and dry environment. Make sure to use gloves and clean off any adhesive from skin, clothing and tools quickly!

A recommended adhesive is Sikaflex 221 which obtains optimum results during temperatures between 15 °C and 25 °C.

Add your adhesive to the bottom of each mount. Immediately lay it in place, use your small marks to line up the panel. You will be able to adjust it very slightly until you have it exactly where you want.  

To finish, add a sealing of adhesive around the base of the mount for extra security.

Repeat this process for each panel and leave for at least 30 minutes to cure and dry. You can leave overnight to be completely sure it’s cured.

Now with your solar panels bonded to your caravan roof you can run your cables inside.

5. Run Wiring Inside

Now you can run the wiring inside but don’t connect the solar panels to the controller.

For multiple solar panels, you can connect them together with a branch adapter, this is available from the manufacturer when adding to an existing system.

  1. Run the positive (red) and negative (black) wires inside your caravan. You might need MC4 adapter cables to do this. These are cables with an MC4 connection to one end and stripped wires on the other which will eventually go into the charge controller.
  2. Running the cables inside can be done in multiple ways. A fridge vent is the easiest way. Or you can drill holes and cover them with a cable entry housing.

6. Connect Charge Controller to Battery

With the panels and cables in place, you can now hook everything up. We will start with the battery to the charge controller. Always connect your charge controller to the battery first to avoid damaging the controller.

  1. Mount the charge controller close to your deep cycle battery.
  2. Find the + and – battery output connections on your charge controller. (Marked with a battery icon)
  3. Wire battery cables to your charge controller. Connect the positive (red) to the positive (+) battery output in the controller. And then repeat with the negative (black) cable and (-) output on the controller.
  4. Identify the positive and negative battery terminals and hook up the cables. Do this with the positive to positive and negative to negative. 
  5. Now you will see a reading in your charge controller. With a screen you might be able to see battery charge levels etc.  

7. Connect Solar Panels to Charge Controller

Finally, it’s time to connect the solar panels to your caravan. Everything should be ready to go.

  1. Find the solar panel input connection on the controller. This is marked with a (+) and (-) next to a solar panel icon.
  2. Wire the positive (red) cable to the (+) input terminal.
  3. Wire the negative (black) cable to the (-) input on the terminal.
  4. Check your charge controller.You should now be charging your battery, you will see current and voltage readings.

How Much Does it Cost to Install Solar Panels on an caravan?

You can install solar panels on a caravan for less than £300. It can be very cost effective. Lots of people carry out the job themselves as it is straightforward. Then all you need to pay for are the tools and components. If you already have a leisure battery you just need to add solar panels and a charge controller. You can pick up 200W starter systems for less than £300!

Of course, you can find professional installers to do the job which will increase the cost as you’ll pay more for equipment and labour.

Installing Solar Panels on a Caravan Summary

I hope this guide gives you insight into how to install solar panels on a caravan.

The steps outlined above can be used on almost any vehicle to glue solar panels to a rooftop. 

Just remember, that your solar array system might be different or use unusual mounts which require an adjusted approach. For example, you might decide to fix a flexible panel in a different method. So take care to work out what’s best for your needs.

Thanks for reading.