Basic Parts of a DIY Camper Solar Setup

Building a DIY solar setup for a Camper Van, RV , Truck Camper, or Travel Trailer requires quite a few parts to work in harmony. This blog post will lay out all of the individual components at a 101 level so that, by the end of the post, you’ll have a good understanding on what the individual parts are, and a good direction to go to learn more about those pieces of your Camper Solar Setup. If you have any questions about any of this, there is a comment section at the bottom where we will answer any questions you may have.

Quick note before we get started.  This is just one part of an overarching “How to Install a DIY Camper Van Electrical System” series.  If you’ve just stumbled on this article directly without seeing that, there are likely some things we’ve already covered.  If you want to check out that step by step guide, you can do that here: https://www.explorist.life/diy-campervan-solar

Also, we have interactive solar wiring diagrams that are a complete, A to Z solution for teaching you exactly what parts go where, what size wires to use, fuse size recommendations, wire lug sizes, and all kind of other stuff to help save you time and frustration.  You can check that out here: https://www.explorist.life/solarwiringdiagrams/

What are the Basic Parts of a Camper Solar Setup?

The basic parts of a Camper Solar Setup are:

• Solar Panels
• Charge Controller
• Batteries
• Inverter/Charger
• Battery Isolator
• Busbar
• Battery Monitor
• Shunt
• 12v Distribution Block
• Fuses
• Wires
• AC Breaker Box
• 110v Plug
• Shore Power Plug
• 12v Switches
• 12v Outlets.

Video: Basic Solar Parts Needed for a DIY Install

Solar Panels

What do Solar Panels Do?

Solar panels are the most obvious component in a solar system. Their job is to gather solar energy from the sun and send it down the wires to the solar controller.

What are the two types of Solar Panels?

There are two main types of solar panels. They are Monocrystalline and Polycrystalline, and the MAIN difference between the two is their efficiency.

Monocrystalline vs Polycrystalline Solar Panels

Take these two solar panels from the same company for example. The first one is the Polycrystalline and the 2nd one is the Monocrystalline.

Take these two solar panels from the same company for example. The one on the left is the Polycrystalline and the one on the right is the Monocrystalline.  The Polycrystalline is rated at 160 watts and has dimensions of 58″ x 26″.  The Monocrystalline is rated at 175 watts and has dimensions of 57″ x 26″.

The two are within an inch in physical size, but the monocrystalline panel is capable of producing 15 more watts per panel. Which means (depending on conditions) you could be potentially gaining an extra 5-10 amps per day per panel if you opt for Monocrystalline over Polycrystalline.

Monocrystalline vs Polycrystalline in the Shade

I’ve seen articles and videos talking about how these two technologies of panels function in terms of shading or cloudy days. There have been lots of opinions given on this, but I have yet to see anything definitive and conclusive to make a blanket statement one way or the other; which leads me to believe… neither one really does a good job in the shade and, perhaps, solar panels just work better in the sunlight.  Don’t overthink this.

What Solar Panels are Best for a Camper?

Since roof space on camper vans is extremely limited, go with the monocrystalline solar panels. You’ll get more power out of the same space leaving more room for vent fans and rooftop dance parties.

The Polycrystalline will also be fine if you are really trying to pinch pennies, but maybe the solar panel isn’t the place to skimp as it would be, likely, one of the more difficult components to replace on down the road.

Charge Controller

What does a Charge Controller Do?

The Charge Controller takes the solar power from the solar panels and then converts it into a form of more ‘organized’ and useful power.  The power is coming from the solar panels at varying voltages. Anywhere from 16 volts to, potentially in the hundreds of volts depending on the setup.  The charge controller regulates that voltage down to the 12-15 volt ballpark (if you are on a 12v battery bank) to properly charge, said battery bank.

What are the types of Charge Controllers?

There are two main types of charge controllers on the market. MPPT and PWM. Those stand for Maximum power point tracking and Pulse width Modulation.

MPPT vs PWM Charge Controllers

PWM is an older technology. Your solar panels must be within a fairly narrow set of parameters to even be compatible with a PWM controller. They are less efficient as they are, pretty much, just a regulator. The only ‘pro’ to a PWM controller is that they are less expensive.

MPPT Controllers are a newer, MUCH more sophisticated technology and have more ‘processing power’ behind them which lets them do more calculations depending on the input voltage to optimize the output voltage to the maximum amount of amps possible to be stored in the batteries for use.

Is an MPPT Controller Worth It?

The ‘buy-in’ fee is a higher, but the added flexibility and performance will give you more bang for your buck in the long run.  Get the MPPT controller. Unless you are strapped for cash… then… save up, and get the MPPT charge controller.

Batteries

What do Solar Batteries Do?

Batteries are simply ‘storage tanks’ for power. They store the power that the solar panels and charge controllerhave made until it’s ready to be used to run computers, charge phones, brew coffee…or whatever.

What are the Main Types of Solar Batteries?

There are three main types of batteries on the solar market. Lead Acid, AGM, and Lithium.

Lead Acid vs AGM vs Lithium for Camper Solar

Lead Acid

These require maintenance and they vent corrosive hydrogen gas. They were the standard for a while, but then technology caught up. Although they can work in some setups, IMO, they are generally more hassle than they’re worth.

AGM & Lithium

AGM & Lithium are the two more commonly used types of batteries in campers currently. Lithium batteries are significantly more expensive up front, but they are cheaper over the long run. Related: AGM vs Lithium – A cost-benefit analysis

What’s the Best Battery for a Camper Van?

Go with lithium. It’s lighter, more powerful, bigger bang for your buck in the long run.  But, here’s my Recommendation if you can’t afford Lithium: Go with the  …BUT!!… Get the SIZE of AGM battery that you can switch out to lithium in the future if you happen to change your mind.

To Clarify, a Battle Born Lithium Battery is about 12 ¾ x 7 x 9 inches and a Renogy AGM battery is 13 x 7 x 9 inches (so, nearly identical).  If you’re living for the moment and need to go with AGM batteries now, you can buy, say, 3 of the AGM batteries now. Once they wear out, or you need more capacity. You can swap in 3 lithium batteries directly in their place, bolt them up, change a few parameters on your charge controller, and you’ll be good to go. Effectively tripling your capacity with the same battery footprint.

Plan for the upgrade now, and it’ll make the upgrade less expensive and easier when it’s time.

Inverter/Charger

What is an Inverter Charger?

Inverter/Charger combo units are, pretty much just that, an inverter and a charger all wrapped up into one nice and neat package.

What does an Inverter Do?

Your battery bank stores power at 12 volts. If you have something, say, a coffee maker or an instant pot… you will need 110 volts a.k.a. A normal household plug.  The inverter takes the 12v power stored in the batteries and converts it into 110v power so you can power those household appliances.

What are the Different Types of Inverters?

Inverters come in a few different types. Square Wave, Modified Sine Wave, and Pure Sine Wave.

What kind of Inverter is best for a Camper?

You’ll be looking for a Pure Sine Wave Inverter. This inverter does the best job of mimicking the power that is ACTUALLY coming through a standard plug you can find in any on-the-grid wall.  Square Wave and Modified Sine Wave aren’t recommended, because, the power they ‘Make’ isn’t a ‘clean’ power and can damage certain electronics and I can’t recommend those because I don’t like recommending products that have an inherent risk of damaging other equipment.

What size of Inverter do I need for my Camper?

Pure Sine Inverters come in sizes from small and portable 300w models all the way up to… a lot.  To get by with “Modest Usage” like running a coffee pot, Instant pot, or induction stove, the most common size I’ve seen AND the size we have in OUR campervan is a 2000w inverter, but if you want to learn, in more detail, how to accurately size an inverter for YOUR setup, you should click here to learn more.

Charger

What is Shore Power?

This is how you can charge your batteries via ‘shore power’: Which is a campground power pedestal or even – simply a plug-in at someone’s house. Shore power is simply an external plugin… somewhere on the grid.  There’s not too much to say about these. You can get these in a separate unit, but typically, it’s easier and cheaper to just get the all-in-one inverter/charger combo package. They charge your batteries at a rapid rate. Anywhere from 40-70 amps DC.

Do I need an Inverter for my Camper?

For anybody looking for the comforts of home, an inverter is a MUST. If your rig is JUST for the random weekend outing… Perhaps run a 12v refrigerator and charge cameras, drones, and such; perhaps you can go without. You really just have to ask yourself ‘What do I plan on powering’ and how much like ‘home’ do I want this to feel.

Battery Isolator

What is a Battery Isolator in a Camper Van?

This is the device that lets you charge your solar battery bank with the engine alternator. It let’s power pass when the engine is running and it closes when its engine is off so you don’t drain your starting battery as you use your solar batteries.

That’s ‘basically’ how it works, but to learn the picky details of installation and what systems you can use it with, there’s more to know…

Busbar

What is a Busbar?

The Busbar is an extension of your battery terminals. When we’ve got a dozen different wires and components that need to be connected to the battery ‘directly’, the top of the battery terminal can turn into a giant birdsnest of wires in a hurry. These just give you a little more room to work with your wiring AND make it easier to see exactly what you’ve got going on and what wires are going to where.

Battery Monitor

What is a Solar Battery Monitor?

The battery monitor tells you the status of your batteries. Like, their capacity, voltage, and how much power is ACTIVELY being generated or lost. The monitor is able to tell us this information by the information provided by the shunt.

Shunt

What is a Shunt?

The shunt is physically responsible for ‘counting’ the amps that are either coming or going in either direction and reporting that to the battery monitor.  If the Battery Monitor is the brain, the Shunt is the body.  The Shunt sits in line of the negative battery terminal and the bus bar. ALL loads should be on side of the shunt that’s away from the battery.

These are typically included with the battery monitor

12v Distribution Block (Fuse Block)

What is a 12v Fused Power Distribution Block?

This fuse block is the easiest way to make fused connections to those low amperage devices and keep everything safe, tidy and organized.  This is how you will run all of your wires to your accessories like lights, fans, 12v outlets, 12v refrigerator, USB ports, etc.

Fuses

What is a Fuse?

Fuses are what protect your wires in case of an over-current situation a.k.a. a malfunction. If there are too many amps flowing through too small of a wire (or if something is malfunctioning), the wire can melt and possibly start a fire. The fuse is designed to ‘blow’ or ‘trip’ at a current lower than that point which will cut the flow of power, effectively shutting off the hazard.

What are the Different Types of Fuses?

There are 3 types of DC fuses I find myself using.

• Spade Fuses
• Resettable Breakers
• ANL Fuses

The type of fuse I pick varies on how it’s being used, the current going through it and the size of wire it’s attached to.

Wires

What do Wires do in a Solar Setup?

Wires transport power from one component to the next. The come in various sizes. “Small wire” for use on lights and fans would be somewhere in the 12-18 gauge realm

What is Wire Gauge?

Gauge is the measurement unit for wires. There’s a more technical way to explain it, but we don’t need to. It’s just like inches, centimeters, miles, or whatever. It’s fairly relative. Just know that 12-18 gauge is pretty small

Oh, and the higher the number goes, the smaller the wire is.

BUT

Once you get into BIG wire for carrying BIG currents like required by the inverter, it gets tricky. As the wire gets bigger, the gauges go 8, 6, 4, 2, 0, 1/0, 2/0, 3/0, 4/0.

AC Breaker Box

What is an AC Breaker box in a Camper Solar Setup?

The AC breaker breaks the flow of electricity to an AC (alternating current) circuit to protect the wire from melting.

Do I need an AC Breaker Box in my Camper Solar System?

Depending on the inverter/charger you get, it may or may not come with an AC breaker installed. If not, and you are wanting to hard wire 110v plugs throughout your camper, you will need to add an AC breaker.

You will need the breaker box, as well as a breaker to protect the wiring and 110v circuits.

110v Plug

What is a 110v Plug?

It’s the household 110v plug and the box you install it into.  Sometimes, people use the plugin that’s commonly found on their inverter to plug in directly. This plug and box is for if you want to have 110v plugs throughout your camper build.

Shore Power Plug

How do I add Shore Power to my Camper Van?

Add an exterior power port onto your camper so you can plug in directly into the van. It looks a little less sketchy than slamming the extension cord between the door and the door jam.

You can get a 30a plug, or a 15a plug.

I’d recommend a 30a plug if you are planning running an air conditioner… or you just never want to have to question anything regarding shore power capacity.

12v Switches

What is a 12v Switch?

These break the power going to lights, fans, outlets or whatever you are trying to control. If you get a REALLY big swtich, you can kill power to your entire system (which is a nice feature to have…)

12v Outlets

What is a 12v Outlet?

This is where you can plug in USB adapters, computer chargers, small inverters or led Christmas lights for some sweet #vanlife Instagram pictures.

12v Outlet vs USB Outlet for Camper Van

Something to consider: On Amazon, a lot of these 12v outlets may come with a USB plug pre-installed in it.  I don’t like that because USB Technology changes every single year. They are always coming out with faster ways to charge our devices.  My recommendation? Don’t install hard-wired USB outlets. Install 12v outlets and have flush mount USB adapters on hand. This is INFINITELY more versatile if you are trying to future proof your build.

Keep Learning:

Now that you’ve learned about the individual components of a camper van electrical setup, the next thing I’d recommend is learning how much battery capacity you’ll need in your camper van electrical system.  Check that out here: https://www.explorist.life/what-size-of-solar-system-is-needed-to-power-a-camper/

Everything that you are learning here is put to use in our FREE Interactive Solar Wiring Diagrams.  If you haven’t yet, check them out as they are a complete solution for a camper van electrical system.  Check them out here: https://www.explorist.life/solarwiringdiagrams/

Remember, this is just one part of a full camper van electrical educational series.  To see all of the individual guides, click here: https://www.explorist.life/diy-campervan-solar

Finally, If you found this guide helpful, It’d truly mean the world to us if you’d share it with somebody who can use it, pin it to pinterest for later reference, or share it to a facebook group when somebody has a question about this subject.  Click the bubble in the lower right corner to subscribe to be notified of future updates and as always, leave any questions you’ve got in the comments below.