It’s easy to understand why people might be nervous about this process:
- Solar panels are a significant financial investment
- The installation process can involve drilling holes in your RV (oftentimes nice, shiny vans)
- Processes involving electrical are often intimidating for DIYers
But fear not!
This process is actually quite simple as long as you have the right tools, knowledge, and a smidge of confidence-all things I intend to discuss here today.
Already have solar panels installed? Skip straight to my article detailing how to charge an RV battery with solar.
Disclaimer: I have faith that most people can achieve some degree of electrical competency. But please remember that electricity is dangerous. Improper installation of electrical systems can cause injury or death to yourself and damage to your personal property. If you have any doubts about your ability to install electrical components safely, please contact a licensed professional to do it for you.
How Many Solar Panels Will You Need?
The first step in your solar journey will be figuring out exactly how many panels you will need, and the proper wattages of those panels. As a general rule of thumb, I tell people that they will probably need to install between one and five, 200-watt solar panels in order to meet the demands of modern day boondocking.
The more power you will be using while you boondock (also known as dry-camping), the more solar panels you will need to sustain the charge of your battery bank.
And while some of you may use zero to no power while camping off-grid, it’s likely that the majority of people will at the very least be powering lights, a couple of outlets, and some plumbing appliances while camping.
With the rise of #vanlife and digital nomadism, many RVers are also charging phones, laptops, and internet devices in addition to typical RV appliances. This level of power consumption is what I am referring to when I talk about “modern day boondocking”.
All of these power-consuming appliances will need to be considered when figuring out how many solar panels you need for your solar panel system.
There are two main routes you can take when calculating how many solar panels you will need:
- Using equations to run the math yourself
- Taking advantage of online calculators
Running the math yourself will be slightly more tedious and you’ll have to trust your mathematical capabilities. Using an online calculator will be a bit easier, but not by a whole lot. Both techniques will require you to know the following statistics:
- Your average power consumption in amp-hours
- The power output of the panels you are installing
- Average peak sun hours in the regions you will be traveling in
I discuss all of these things in detail in the article I wrote last week that goes over how many solar panels someone will need for their RV.
Give it a read to learn about the information required to calculate solar usage, and to learn the equations used to calculate how many solar panels you will need for your build.
If you have one of these sweet, towable expedition trailers, and want to utilize solar power, do some research on portable solar panels and how you might be able to incorporate them into your power system.
Tools and Materials
Once you have determined your required amount of solar panels and have purchased them, you will need to gather a handful of tools and materials to get the job done. All of these things should be easily purchased at your local hardware store or any big home improvement store such as Lowe’s or Home Depot.
There will be varying opinions on exactly how to accomplish this task. The following information will be based on my own past experiences.
Having all of these tools on hand will make your life quite a bit easier during the installation process:
- Drill and drill bits
- Impact driver and driver bits
- Hole saw
- Small pry bar
- Caulk gun
- Tape measure
- Small dykes
- Wrench set
- Sturdy ladder
- A large piece of cardboard
- Spray bottle filled with 99% isopropyl alcohol and paper towels (for clean up)
This list will encompass all of the materials you will need to get the job done:
- Solar panels
- Panel mounting brackets
- Cable gland
- A tube of adhesive caulk and a tube of silicone caulk
- Appropriately sized stainless steel bolts, nylon lock nuts, and washers
- Cable ties
Solar Panel Installation
I could write a long essay detailing every single tiny step in this process, but I don’t think anyone wants to read that so I will do my best to keep it concise. Don’t worry, it’s not a super complicated process.
If you are more of a visual learner, check out this great instructional video by Travel New Trail:
His process for installing the panels varies slightly from mine but will have most of the same steps. Any differences are simply a matter of personal preference.
First, determine the best location for the solar panels on the roof of your rig. It should be a location that will maximize sun exposure and allow ease of access for cleaning and maintenance.
You will need access to the space in between your roof and your ceiling panels so go inside your rig and open up the section of your ceiling that will be directly under the panels.
After securing the mounting brackets to the panels, lay the panels on the roof of your rig, roughly in the desired location. You will probably need two pairs of hands for this process so you do not risk damaging your RV, the panels, or yourself.
Use a tape measure to ensure panels are sitting squarely on the roof. This is purely for clean aesthetics. After finalizing the location, grab your drill and a drill bit that will create a hole big enough for your bolts to drop through.
Mark the locations of the holes on each of the mounting brackets onto the roof of your RV. Shift each solar panel aside and drill these holes through the roof of your rig.
Crucial waterproofing steps: squirt a generous amount of silicone caulk into each hole and apply a bead of adhesive caulk that creates a ring around each hole.
The mounting brackets will be repositioned on top of the holes, squishing down directly on top of the rings of caulk. I suggest laying cardboard down inside your RV to prevent caulk from dripping onto any finished flooring.
After the caulk is applied and bolts are dropped through, go inside your rig and fasten the washers and nylon lock nuts onto the bolts. Grab a buddy and have them hold the tops of the bolts securely as you tighten the nuts from below.
The last step in the panel installation is to seal the tops and bottoms of the bolts with more silicone caulk, fully encasing the heads of the bolts from the tops and the nylon lock nut from below.
Don’t pack up yet, there’s still a bit more work to do on the roof.
Determine where you will want the solar wires to pass through the roof of your RV. It should be somewhere that allows for the shortest path possible to the charge controller on your electrical control panel.
Using an appropriately sized hole saw for the size of your cable gland, drill a hole at your pass thru location. Install the cable gland, as per instructions on the packaging. Every cable gland will be slightly different so it’s best to follow the manufacturer’s installation instructions.
Make sure to use an abundance of silicone caulk every time you drill a new hole in your RV to prevent water leakage: the RV killer.
Paper towels and isopropyl alcohol will be your best friends during the cleanup process. Isopropyl will soften and dissolve extra caulking and allow the paper towels to do their job.
How to Hook Up Solar Panels to RV Batteries
Nice! You have your panels installed and are ready to move on to the next step: connecting your panels to the charge controller and your RV batteries.
But wait! What the heck is a charge controller? And why do you need one?
The charge controller in your RV is going to regulate the flow of energy from your panels to your RV batteries. If you were to connect your solar panels to your battery bank without a charge controller, you would run the risk of damaging your batteries by overcharging them or fully draining them.
You can think of solar charge controllers as the brains of your solar power system.
Most people use deep-cycle batteries in their RV power system, with the two primary types of batteries being lead-acid and lithium.
Lead-acid batteries provide a steady stream of power and can be safely used until they are between 50% and 80% discharged.
Do-it-yourself RVers with a higher budget might spring for lithium batteries in their RV. Lithium batteries have a longer life, are lighter, more efficient, and more powerful than their lead-acid counterparts.
The Hook Up
Any basic solar power system will need the following components:
- Solar panels
- Photovoltaic (PV) wires
- Charge controller
- Battery bank
From top to bottom, your system will be connected as follows: solar panels connect to the charge controller, and the charge controller connects to the battery bank. Simple as that!
All connections between your panels and the charge controller must be made using photovoltaic wire. This wire is specifically made for solar power systems and comes with rugged insulation to protect the wires that live on the exterior of your rig.
Things to remember when hooking up your system:
- Polarity: It is crucial that the positive terminals connect to other positive terminals, and that the negative connects to the negative.
- When putting tools to the positive and negative terminals on your battery, always wear thick rubber gloves. Never allow a metal tool to touch both positive and negative terminals at the same time, otherwise, you’ll be in for a shocking surprise.
- Once installed and exposed to sunlight, the PV wires coming off your panels will have electrical current running through them. Cover your panels with a blanket while hooking up your system in order to ensure that no sparks fly.
Solar panels charge your batteries, which in turn provide you with a steady stream of 12 volt DC power. This is great for powering many appliances in your RV, but some things will need 120 volt AC power. If you want to use outlets, air conditioners, and water heaters, you will almost certainly need AC power in your rig.
To achieve this, simply install an inverter in your RV. The inverter will take DC power from your battery bank, convert it to 120 volt AC power, and send that power to your 120 volt breaker. From the breaker, you will be able to control where that AC power goes, and which appliances are being supplied with that power.
Inverters are expensive, heavy, and somewhat tedious to install, but trust me, it’s worth it.
I hope you are able to learn a thing or two while you go through the process of installing your solar power system.
Solar power is an incredible renewable energy source and should be utilized as much as possible when you camp. The more self-sufficient we can be while boondocking, the less of an environmental impact we will have on the beautiful, natural spaces we love so much.
So good luck! Be safe, be precise, and don’t be afraid to contact your local RV technician if you need a hand with the process. Cheers!