Power is essential for van living. If you’re converting your own camper van and you’re not an electrician, installing an electrical system might seem daunting. But with a little education, the right tools and plenty of patience, it’s possible to do it yourself.
Solar is the most popular way to power #vanlife and will be central to this DIY guide. We’re going to break down the components you need for a complete electrical system and how to install them.
Editor’s note: We recommend consulting with a licensed electrician before performing any electrical work.
What we used: Two Renogy 100W 12V Mono Solar Panels
Purpose: Your solar panels absorb light from the sun, convert it into electricity, and transmit it into your electrical system.
What we used: 30A PWM Wanderer Li Charge Controller
Purpose: Your solar charge controller is designed to increase battery life and improve system performance. The Renogy Wanderer-Li utilizes PWM (pulse width modulation) charging, considered the most effective means to obtain constant-voltage battery charging. In short, it regulates the current from the solar array according to the battery’s condition and recharging needs.
Editor’s note: We installed Renogy’s 200 Watt 12 Volt Solar Starter Kit, which includes the panels and charge controller listed above in addition to all necessary mounting and wiring hardware.
What we used: Renogy Deep Cycle AGM 12V 200AH
Purpose: Your battery stores electricity created by the solar system. For camper van living, you want to store electricity at 12V DC (direct current) which will effectively power anything that runs on DC current such as lights, an exhaust fan, refrigerators and USB outlets.
What we used: Xantrex PROwatt SW 1000-watt Inverter
Purpose: An inverter is necessary for powering 110 Volt AC (alternating current) devices, such as laptops and other electronics that require a 3-prong wall outlet.
WHAT TO CONSIDER WHEN CHOOSING SOLAR PANELS
RIGID VS. FLEXIBLE
Rigid panels: Rigid solar panels feature cells mounted under tempered glass. These are more durable and less expensive per watt when compared with flexible panels. They also are designed for harsh outdoor conditions and easier to aim at the sun.
Flexible panels: Flexible solar panels feature flat, molded cells with a layer of protective plastic. They’re lighter, easier to install, bendable up to 30 degrees and typically lower profile. But they are prone to scratches and have a shorter lifespan than rigid panels.
What we used: Rigid panels
POLYCRYSTALLINE VS. MONOCRYSTALLINE VS. AMORPHOUS
Polycrystalline: Cheaper and larger per watt
Monocrystalline: More efficient and space-saving, more expensive
Amorphous: Not recommended for RV/camper van living. They are less efficient, heavier and more expensive per watt.
What we used: Monocrystalline panels
WIRING IN SERIES VS. PARALLEL
Series: Wiring solar panels in series means wiring the positive (+) to negative (-) charges to increase the voltage while maintaining amperage. Advantages to this are that it is cheaper and easier wiring and does not require fuses.
Parallel: Most PWM charge controllers require parallel wiring. Parallel wiring is better in certain shade conditions in which one panel is shaded but not the other. Wiring in parallel allows you to get full voltage from the sun with one panel. Parallel wiring requires bigger fuses and more expensive wiring.
What we used: Parallel wiring
WHAT TO CONSIDER WHEN CHOOSING A BATTERY
FLOODED LEAD ACID VS. AGM DEEP CYCLE VS. LITHIUM ION
Flooded lead acid: These batteries are the most economical and feature the oldest technology. However, they require more maintenance and ventilation than other options.
AGM deep cycle: The ideal choice for most van setups, AGM batteries can be discharged and recharged frequently. They hold their charge well and require less maintenance but have a shorter lifespan than FLA or lithium options.
Lithium ion (LiFePO4): These batteries can be discharged and stored empty without long-term damage. Disadvantages include the high price tag and inability to charge below freezing.
What we use:d AGM deep cycle battery
Pro tip No. 1: Match your solar panel wattage to your battery Ah capacity. For example, we paired our 200-watt solar array with a 200Ah battery.
Pro tip No. 2: Never fully deplete your battery. If your battery drops below 50 percent, you risk shortening its lifespan and damaging it. So, if your power consumption is about 100Ah per day, you need a battery that is at least 200Ah.
DESIGNING THE ELECTRICAL SYSTEM
Most critical to installing an electrical system is diagramming it in advance. Each diagram will vary according to individual needs, but all should contain some universal elements including fuses, switches and ground points.
Additional electrical components needed: Marine battery cable, 18AWG strand wire, Marine grade 14AWG wire, ring terminals, disconnects, wire twist connectors, cable splice kit, cutoff switches, fuse holder, fuses
Tools needed: Electrican’s multitool, klein ratcheting screwdriver, electrical tape, cordless drill
WHAT TO CONSIDER WHEN DESIGNING AN ELECTRICAL DIAGRAM
Grounding and switches: “Grounding” in a van electrical system means connecting to the vehicle’s chassis. As a general rule, make sure you ground both your battery and your inverter (if using one). You’ll also want to incorporate switches between main electrical components so you can easily cut the power from different sources in an emergency. We installed switches for our main power source, our solar panels and our inverter.
Fuses and fuse boxes: Fuses are effective safety measures in any electrical system. Fuses are designed to blow and break the electrical circuit if too much current flows through. We recommend wiring everything into an automotive fuse box using blade fuses. Labeling each component on the fuse box will keep things organized, especially if you intend to add to your electrical system in the future.
Pro tip: Check the manuals for your inverter, charge controller and batteries for manufacturer-recommended fuse sizes.
Skills required: Cutting and crimping wires. An electrician’s multitool is used to crimp wires, which connects them. We recommend using heat-shrink crimp connectors due to the moisture buildup that occurs in vans. Heat-shrink crimp connectors (as opposed to PVC or nylon options) offer a permanent, waterproof connection.
INSTALLING YOUR ELECTRICAL SYSTEM
Step 1: Mount and wire your solar panels
Pro tip: Do not connect your solar panels to the charge controller until you connect the battery.
For wiring in parallel, all the positive wires go together and all the negative wires go together. You’ll need to run the wire into the van’s interior, which requires cutting a hole to allow the wires to pass through the roof. Be sure to apply primer, paint and clear coat on drilled holes to prevent corrosion. To keep the cables from chafing the roof, we used protective tape to hold them to the bottom of the solar panels.
We laid out the location of our panels in advance and used 3M VHB tape on the brackets to adhere them to the roof. Alternatively, you can drill holes into your roof, but this is much more time-consuming and unnecessary. Seal all brackets and your cable glands with dicor lap sealant to prevent water contamination.
Step 2: Mount the charge controller
You’ll want to mount the charge controller in your van’s interior, preferably in a designated “electrical closet”. You’ll want to make sure it’s easily accessible.
Pro tip: Leave a few inches of space around the charge controller to allow for ventilation.
Step 3: Wire your charge controller to your battery
Run wire from the positive battery terminal on the charge controller to one side of the main on/off switch. This allows you to kill the connection to the battery, if needed. From the other side of the switch, connect the wire to your inline fuse holder. The fuse should match the current rating of the charge controller. To complete the circuit, run the wire from the other side of the fuse holder to the positive post on your battery. Then, connect the negative wire from the battery post to its equivalent on the charge controller.
Pro tip: Do not disconnect the battery when the solar panels are hooked up to the charge controller. Always disconnect your solar panels FIRST when you need to cut off power.
Step 4: Wire your solar panels to your charge controller
Make sure to wire positive to positive and negative to negative.
Step 5: Wire your load terminals to the charge controller
Run wire from the positive terminal on your charge controller to the blade fuse box and then wire from the negative terminal of the charge controller to either a bus bar or the negative connection on your fuse box, if present.
Step 6: Wire lights, switches and fans
We previously wired our fan and lights to our auxiliary battery, which is located under the driver’s seat. We used 18AWG gauge wire for the lights and 14AWG gauge wire for the fan. This preparation saved us time as now all we had to do was connect everything together to run off the house battery. We integrated a dimmer switch with the ability to control individual sets of LED lights, one front-positioned and one rear-positioned.
Step 7: Wire the inverter to the battery
If you’re integrating an inverter into your electrical system, this is the point at which you should wire it to your house battery. We recommend mounting it in your electrical cabinet — ideally off the ground. We integrated an on/off switch between the battery and the inverter to cut power in case of an emergency.
Pro tip: Use a power strip with a heavy-duty surge protector if you need more than the number of three-prong outlets included on the inverter, in our case two.
B2B charger or smart battery isolater: Although we haven’t installed this component yet, we plan to. A B2B charger allows you to charge your system from the alternator, which produces a lot of power when you’re driving. A battery isolator pairs your leisure battery with your existing vehicle system (essentially serving the same function) but does so less effectively than a B2B charger, as it doesn’t provide a full multi-stage charge. All quality B2B chargers will ensure that your starter battery doesn’t get drained faster than the alternator is charging it. We plan on installing a Sterling Pro Batt Ultra Battery to Battery Charger.
Sizing your electrical system: Calculating how much power you need varies depending on what components you plan to install. We need to power a fan, LED lights, an inverter and eventually a refrigerator. Other components that might require electric power include heaters, toilet fans and water pumps. Check out this helpful resource for calculating your power needs. In addition, this electricity calculation worksheet is useful if you know the number of watts each component uses and can estimate how many hours a day you plan on using them.