Editor’s note: Electrical work can be dangerous and should be taken seriously. We recommend you consult a professional electrician or undergo formal training before beginning any electrical project.
A sustainable source of electricity is vital for any off-grid van lifer. While a dual battery or battery box setup helps power devices like portable refrigerators, coffee makers or smartphone chargers, it’s not always the most effective long-term solution.
A popular and more efficient reliable energy source is solar power. Even in areas without constant direct sunlight, solar power can be harnessed.
Installing a solar power system on a camper van can be done in a variety of ways depending on individual needs and vehicle setup. Instead of paying an electrician, adventurers can invest in a solar kit to install themselves. You’ll need the proper tools, a basic understanding of circuitry and a free weekend to dedicate to the project.
Here are a few tips on what’s involved.
Editor’s note: Installing a solar kit is system-specific and varies based on vehicle model, equipment, intended use and permanent components. This walkthrough is meant to serve as a general resource for getting started. Specifications like appropriate wire and fuse sizes are system-dependent. We recommend consulting an owner’s manual for specific instructions whenever possible.
ACQUIRE THE NECESSARY EQUIPMENT
The first step for any camper van project is to gather the correct tools and equipment. Here’s a comprehensive breakdown of the exact tools, solar components and batteries required for the build.
- Electrician’s multitool
- Ratcheting screwdriver
- Cordless power drill and bits
- MC4 assembly tool for electrical components
- Electrical tape
- Caulk gun and caulk
- Wire cutters and crimpers
These tools help with everything from securing solar panels onto the camper van to drilling all necessary holes. For fastening the panels, a ratcheting screwdriver and cordless power drill are needed, whereas the wire cutters, electrical tape and MC4 assembly tool are required once the wiring process begins.
Don’t underestimate the need for a caulk gun and caulk, either. These are important to assure that any cracks generated from drilling holes during the installation process are properly filled and sealed.
Same goes for a ladder. It affords easier access to hard-to-reach spots on the van while also providing a sturdy platform for working. It’s wise to use a second person as a ladder spotter, as well.
As is the case with much of this walkthrough, a comprehensive understanding of how to use each of these tools isn’t just recommended – it’s vital.
SOLAR KIT COMPONENTS
- Two 100-watt, 12-volt panels
- Charge controller
- Adapter kit
- Tray cables
- Mounting brackets (Z-shaped types recommended to fit the ridges of irregular van roofs)
Tip: If a DIY project is too large an undertaking, the camper van accessory company Renogy manufactures solar kit packages. Its 200-watt, 12-volt Solar Kit is a great starter package that costs roughly $465.
Two 12-volt DC batteries and an inverter complete a basic solar power system. An inverter isn’t necessary for powering 12-volt-compatible electronics such as Dometic coolers or MaxxAir fans, but it is used for converting direct current to alternating current. One is also required for charging computers and other 120-volt appliances like smartphones or microwaves. An inverter is grounded to the vehicle chassis.
Battery choice comes down to personal preference and desired utility. Three types are most applicable for van conversions:
- AGM batteries: A standard battery for many solar systems.
- Gel batteries: Less popular, these won’t function well in high-heat environments.
- Lithium-ion batteries: An advanced battery option that also comes with a higher price tag.
DETERMINE YOUR RIG’S POWER NEEDS
The necessary number of solar panels and required battery size depend on individual electricity use, or watt-hours (Wh). To figure out specific Wh, multiply the average number of watts consumed daily by the average number of hours power is being used.
Next, convert the estimated daily Wh into amp-hours (Ah) to determine the necessary battery capacity. This is done by dividing Wh by the intended voltage. In this case, desired voltage is 12, making the equation Wh divided by 12. The solution represents the minimum battery capacity needed.
Figuring out the exact number of solar panels needed requires understanding each panel’s maximum wattage. To do this, first estimate the average amount of full sunlight per day. Then, divide Wh by those sunlight hours to get the necessary wattage.
To avoid unnecessarily draining batteries, battery capacity should be twice the system’s estimated power consumption. A good rule of thumb is to match solar panel wattage with battery Ah capacity.
MOUNT THE SOLAR PANELS
Ready the panels by determining mounting brackets’ placement on your vehicle, then attaching all of them. Keep in mind some placement arrangements might affect a vehicle’s aerodynamics.
Panels can be installed in a series or parallel to one another. Each has its own set of advantages and disadvantages:
- Series: Results in increased voltage and higher efficiency, but as all the panels form one line to the charge controller, a negative effect on one panel (such as shade) affects the whole system.
- Parallel: Multiple pathways connect to the charge controller, which means panels function independently, and shade on one panel will not affect output of the others. However, the additive amperage means lower total system efficiency and higher associated costs.
After deciding on a placement strategy, drill all holes needed to route the panel wiring across the rig. Then, use self-drilling screws to attach each panel on the vehicle. It’s recommended to make sure each screw is watertight once completely tightened. A butyl kit is a great option for doing this.
MOUNT THE CHARGE CONTROLLER
Charge controllers ensure the solar panels don’t overcharge the batteries, so mounting one in a convenient location on the interior of the vehicle is crucial. Allow for a few inches of space around the controller for ventilation
WIRE THE BATTERIES
Editor’s note: It is critically important that solar panels not be connected to a charge controller before the batteries are connected.
For a van system with more than one 12-volt battery, wire each in a parallel manner by first connecting each positive terminal together, then each negative terminal together.
WIRE THE SOLAR PANELS
The wiring process depends on the number of panels used and whether they were installed as a series or parallel.
For one panel, connect the positive wire to the positive charge on the controller and the negative wire to the negative charge on the controller. For multiple panels, wire them in whichever series they were installed or parallel to one another.