The following is my attempt to explain our 500W truck camper solar system and why we made the choices we did. If you are planning to do your own system please educate yourself well in regards to electrical currents and understand the risks involved. If you wire a battery so that poles arch the best-case scenario is that you will melt wires… the worst-case scenario is that the battery will explode! This is serious stuff and should be treated as such.
Creating our truck camper solar system was the biggest, most expensive, and most difficult renovation we did on our rig YOLOM. I spent a solid month just doing research before ordering the first piece. The initial install took about a week, but over the course of 6 months, I added more solar panels and wired new gear and outlets into the system. I was able to add these pieces because I made sure that the backbone I created could handle the potential for a larger system ahead of time. The last thing you want to do is build a solar system and then have to replace it because you didn’t take into account the need for potential growth.
Quick Links for this Truck Camper Solar System Series
Whereas this post is all about the choices we made for our truck camper solar system and how we came to those decisions, the following video covers the actual install process. I hope you enjoy.
Initially, I thought about getting an all-in-1 package from a solar manufacturer. After reading through some blogs it seemed like there was something missing about these packages. They seemed overly large for the kind of power they generated. I then stumbled upon Handy Bob’s site and started to educated myself on the importance of DC wiring techniques and how the solar install industry on a whole really doesn’t understand the full-time traveler’s needs. They are designing their solar systems for weekend warriors, not full-time nomads. I think efficiency isn’t a priority for the all-in-1, but rather revenue and cutting corners to save cost. Or perhaps they just don’t understand their product.
All-Inclusive Solar Bundles
So my warning to you is to stay away from the all-inclusive solar bundles and even if you pay someone else to install a solar system read this post and Handy Bob’s website to understand what should go into a real solar system. This will allow you to make some educated decisions about how to spend your money and what kind of power you should expect to be generating from your particular system. This is complicated, but it isn’t magic. However, if you go in blind you will end up with an overpowered system that still finds a way to underperform.
Know Your Electrical System
If you choose to take on this task of becoming a novice electrical engineer than by the end of the process you will know your electrical system inside and out. Which is a great thing since everything on a camper/RV/Campervan seems to break and you will know how to fix it. Take it slow and research, research, ask questions and research some more. If you have questions feel free to ask questions in the comment section below and I will do my best to answer it.
Calculate Potential Power Load
First, we had to figure out a potential load for how we wanted to live on the road. This involves some research as well as basic math skills. Immediately, I realized the size and weight limitations of our rig would limit our battery size, but I still wanted to maximize our truck camper solar system for our needs. More available power means more possibility for time off the grid. So this involved gathering all our devices and getting their maximum power draws.
Manufacturer Listed Power Draws
Computer 1: 20V x 4.25A = 85W
Computer 2: 20V x 4.25A = 85W
Camera Battery charger: 8.4V x 1.2A = 10W
Drone charger: 13.05V x 3.83A = 50W
Hand VAC: 24V x 0.21A = 5W
Original Fridge = 12V x 15A = 180W/hr (This one was tricky)
Fan = 12V x 3A = 36W
Lighting = Minimal once changed to LED
Phones = 12V x 1.6A = 19.2W x 2 phones = 38.4W
Coffee Maker = Nothing. We changed to a manual french press.
I think our AeroPress makes a better-tasting cup of coffee. It just takes a little more effort.
Above are the actual numbers I started with. Manufacturer numbers are rarely what a load looks like and most things don’t draw a steady load constantly. I will go over our actual loads later on in this series. Like ours, things will evolve during your processes as well I’m sure.
Next, I realized batteries are rated for Amp Hours, not Watts, but solar panels are rated in maximum watts generated per hour. So I had some calculations to figure out. If you are new to calculating power draw just remember West Virginia (W VA) which is an easy way to remember that Watts = Volts x Amps.
3-way Fridge vs. Compressor fridge
You should also know that the above figures are the maximum draws provided by the manufacturers and in most cases, devices pull far less power. This is not true of the 3-way refrigerated that was factory installed in the Palomino camper. It actually pulled 15.5A all the time. Slightly higher than the listed amount on the manual. It never dropped off like our new Dometic CFX fridge. Here is a link to the post on replacing the old unit with our new one. We found out later that in order to support the 3-way factory refrigerator our truck camper solar system would have needed to be more than twice as large. In with the new and out with the old.
Other Appliance Considerations
I also looked at other appliances like microwaves, toasters and a small A/C unit. I quickly realized that these would require a substantially bigger system that our truck camper just couldn’t accommodate due to the F-250s gross vehicle weight rating.
Total Truck Camper Solar System Target
So with the old fridge included the maximum draw for our truck camper solar system was about 490W/hr and most of these devices would never be on at the same time, but would only need to charge for a few hours a day at most. Like I said above, I wrongly assumed the fridge would only pull its full power for a short time and then go into power cycles as it maintained temperature. So I thought an anticipated 200W/hr power draw would be plenty. I was wrong, but we eventually went to a more efficient fridge which is way better than scaling up the entire solar system to support a nearly 9-year-old fridge. I also do not like the ammonia limitations of the 3-way fridges.