How To Put Solar Power In A Sprinter Van
Which battery should you choose?
When we first started our van build, we had no prior knowledge about DC 12 Volt, electrical, or solar. In fact, the majority of our solar set up knowledge was through trusty ol’ google searches.
To start, we found that there were two general ways to approach our battery options.
2x 6-volt batteries. This route was cost friendly, and the batteries were easy to find at stores and online.
One 12-volt battery. This battery had an easier installation and a more simple setup, but it was much more expensive and heavier than the latter option.
The next decision we had to think about when purchasing our battery was if we wanted a sealed or flooded battery
A sealed battery (AGM/gel) : Has low maintenance, can be in your living space without ventilation, and has a faster charge rate. This also means that it was more expensive.
A flooded battery : Cheaper and has a longer lifespan, but it has higher maintenance and must have proper ventilation.
Our goals for our electrical set up were to keep everything as simple and safe as possible. We decided to go with the low maintenance single sealed 12v Lifeline GPL-8d battery. This battery was more expensive than the two 6 volt batteries, but we decided to go with the single 12v battery because we wanted to store it in our living space and we didn’t want to worry about it leaking.
The set up is also much easier because you don’t have to worry about using additional wiring and you don’t have to build an extra compartment space for storage.
After we bought our battery from Amazon, we had to decide where the battery system was going to be placed. Our two main sources for charging our battery were going to be through the solar panels and the alternator. We felt that placing the battery in the front of our van near the driver's seat was the best option because it was closest to the charging sources. We also placed our solar panels at the front of our roof to keep everything in the same general area.
Pro Tip: Do not let your AGM battery go below 50% charge for a longer battery lifespan.
Know Your Wiring
This chart below isn’t really a step in the process, but it’s something we used throughout setting up our power in our sprinter van.
We learned for wiring, that it's better to be a size too big than a size too small. The reason for this was because the larger wire has less resistance and will allow more electricity to flow through it, faster.
We also recommend to always use real copper wires because it’s what the pro’s use.
It’s important to also solder your wires to help keep them together. A shrink wrap and heat gun on your connections are a must when wiring lights, water pump, and other items that require power. This helps keep everything together so that you don’t have any loose connections.
We also learned that its the little things matter the most. Having the right tools, parts, n’ bits makes it easier to set up your 12v battery and solar power in your van.
While we were wiring our van, we tried to budget by only purchasing the connectors and fuses as we needed them. If we could do it again, we would have bought a kit with an array of sizes. This would have saved us so much time and trips to ace hardware.
*Also keep a fuse kit too.
Installing Our Battery Monitor.
For our battery monitor, we went with a Trimetric 2030 because we originally wanted to pair it with the SC 2030 Solar Charger. However, when the solar charger was shipped to us we got a faulty one. So, we decided to go a different route for our battery charger. More info about that in the next section.
The Trimetric 2030 has a lot of great features like percentage full, days since last full charge, and a lot more. One good thing about it is that it included presets to calibrate to whatever battery you're using. Everything down type, size, voltage etc..It made the setup super easy.
Our battery monitor required a 500a/50mva Shunt.
WTF is shunt?
Well, a shunt an electrical conductor joining two points of a circuit, through which more or less of a current may be diverted. Basically, you need it to measure the battery levels???????????? Sure. You need it.
The next part is something we overlooked. During the installation of the 500a/50mva Shunt, all negative connections must be connected to the shunt and not the negative terminal of the battery, otherwise, you’ll get an inaccurate read from your battery monitor.
This resulted in us scratching our heads wondering why our battery would never go under 99% full, even after we used a hair dryer, and a vacuum cleaner at the same time. Once we figured it out we felt that it was important to thoroughly read through all of the instructions... Twice.
Battery Management System
The battery management system ensures you that your battery is charging properly.
We knew our two main sources of how we were going to charge our battery which are the solar panels and the alternator while driving.
We learned that it is not good to have multiple inputs of charge going into the battery without a charge controller. My uncle who is an electrician recommended a product by CTEK, a leading performance battery charger company. We bought the CTEK 250s Dual and CTEK 250s smart pass combo. It provides an input for solar, alternator, and even a wall charger down the road if we needed it.
So what that means for us is that we could be driving getting a charge from the alternator as well as the solar panels and shit won't explode.
The charge controller does exactly what it implies and controls the charge going into the battery. It works amazing and the instructions were pretty simple for someone without an electrical background.
We run a creative studio out of our van, which meant we needed a good amount of power to charge all of our equipment so we can work on the go. We didn’t want to rely on shore power and really liked the idea of being completely off the grid.
After doing a bit of math, we quickly saw that 50-100 watts of solar wouldn’t cut it. The solar panels we purchased were two Grape Solar 160 Watt Panels. We bought these because they are large they give us a total of 320 watts, which was power we needed.
We connected these panels in a parallel circuit by using two 2 to 1 MC4 Connectors (one for negative connections, and one for positive connections) We drilled a round hole in our roof, fed the line down through a waterproof cable gland nut to prevent leaks. Then we sealed it with butyl and silicone
Next, we connected the positive wire to the charge controller with a 30a inline fuse in between. The negative wire is CONNECTED TO THE SHUNT.
We fabricated our own mounts to attach our solar panels to the rails of our sprinter van. We used z brackets. nuts, bolts, lock nuts, and straight brackets to make it all happen. If you want to see some photos of how we did this, check out this blog post.
Pro Tip: Keep your solar panels clean for maximum power.
Time for the inverter.
An inverter gives you the ability to plug in your standard household American plugs into your power source.
The type of inverter we chose was a pure sine wave inverter because we wanted to be able to run whatever electronic device we could use. A modified sine wave Inverter is limiting to which electronics can be powered.
The bigger question was, how much juice does our pure sine wave inverter need to pump out at once? We needed to be able to charge cameras, computers, led lighting equipment, and phones all at the same time. This is because we run our entire studio out of our van, and occasionally Starbucks. So, we went with a Nature Power 2000 watt pure sine wave inverter.
The inverter can easily charge both of our computers and charge our camera batteries and even light batteries all at the same time. Lexi is even able to use her hair dryer and hair straightener which can draw a lot of power.
Once we began converting DC to AC power, the chance of getting zapped greatly increased. From the inverter, we installed a battery disconnect switch so we could easily and safely turn the power to the inverter completely off. After that, we installed a 300a anl fuse and connected that to the battery.
We also installed a secondary outlet by our bed so we could charge stuff without having to run a cord all the way to the front of the van. This makes our van feel less like a van and more like a house.
With the power cut switch in the off position, we removed the face of the inverter which has terminals to hook up an additional outlet. We wired it behind our kitchen counters to the location of our outlet.
To hook up the rest of our power demanding things like lights, refrigerator, and fan..we wired all of the positive wires to a fuse box first, and then to the battery. ALL NEGATIVE CONNECTIONS MUST GO TO SHUNT.
We had to buy a longer bolt that fit the shunt because we had so many grounds going to the shunt.
So far, in the last year, we’ve had enough power to charge everything we need. We really like our setup because it was fairly easy to do and it has worked really well for us.
If you have any questions, feel free to leave a comment or send us an email! We can try to help in any way we can.