Most of my build experience is with mechanical things. I’m comfortable with drills and saws and glue, but I have less experience in the world of wires. My lack of experience, combined with the more serious consequences of poor electrical work, meant that the planning phase of this project was a little more in-depth.
I started by figuring out what I want. I decided to run a 12V DC only system. I figured all of what I need (lights, fan, fridge, phone charger) can run on DC, and not needing an inverter is good for many reasons. Inverters are expensive, add another component, and take a significant amount of power, meaning you need a bigger battery. If I decide down the road that I want AC outlets, I can add an inverter to the system without too much trouble.
I decided that I want to be able to charge my battery two ways: from solar and from the van’s alternator. This gives me a reasonable amount of redundancy in that I should be able to charge my battery off solar when I’m parked for a long period, and I should be able to charge off the alternator if the sun is gone for too long. Like the inverter, I might add a shore power charger later so that I can charge my battery by plugging it into a wall outlet, but for now I’ve left it off the list. I bought a MPPT solar controller/DC-DC Charger that will both manage my solar panels and let me charge off the alternator without instantly draining my battery.
Next up was battery and solar array sizing. I used an online calculator and got a sense of what other people do, but in the end my van is quite space limited and I am guessing at my needs. For solar, I am using two 100 watt solar panels that just barely fit on my roof, so if that’s not enough I’m gonna have to get creative. I am starting with a single 100 amp hour battery, with the idea that if needed I can add another one.
With my components chosen, I had to figure out how to connect them all. I pretty much consulted a bunch of other van lifers on the internet and the manual for my MPPT/DC-DC charger, made a little wiring plan, bought some wire and terminals, and then I was ready to actually start building stuff.
