Why we chose solar:
Amanda and I wanted to install a solar-powered electrical system in our RV for a few reasons: we like self-sufficiency, support renewable energy, and didn’t want our electrical needs to limit our ability to adventure/explore. We wanted the capacity to boondock for at least a few days to a week at a time. Solar can provide us on-demand AC and DC power without running generators or plugging into shore-power.
If you are like us, the process of learning about and installing an off-grid RV or van solar electrical system seemed intimidating – but it doesn’t need to be!
Begin by reading a LOT. It’s impossible to have ‘too much’ knowledge when working with electrical systems – they can be dangerous. BE CAREFUL and when in doubt, CONSULT A PROFESSIONAL!
Our van solar system:
We chose flexible, 100-watt, 12-volt monocrystalline panels. They are lightweight and can be mounted more easily and without drilling ANY holes in our roof. Our panels weigh roughly 1/10th of what a conventional metal-framed, tempered-glass panel weighs. Prioritizing weight means our panels cost 60% more.
We bought our panels from ML Solar, a solar supply warehouse in the SF Bay area. Many places don’t stock a large supply of solar supplies, or if they do they tend to cost a lot more than Amazon, but they were having a sale so the three panels cost us $195 each (comparable to Amazon, similar panels here), for a total of $585. On bright, sunny days our panels put out 60+ volts, producing over 15 amps (controlled by our MPPT charge controller). This power generation capacity has been sufficient to keep our van solar battery bank topped off in all conditions.
The Charge Controller
We chose a Solar Epic Tracer 40-amp MPPT (Maximum Power Point Tracking) charge controller (approximately $193, also available on Amazon). It’s capable of managing 150 volts open circuit voltage and puts up to 40 amps into the battery bank. It has load terminals which can supply 20 amps DC to our fuse panel. A monitor plugs into the Tracer and gives us up-to-the-minute information including how much power we are generating, how much power is going into our battery bank, and how much power our DC electrical system is using. It also logs our total electrical generation over days, weeks and months. If you want to get really fancy you can plug into a computer and sort all that info with graphs and charts – neat.
We found a great used battery warehouse in the SF Bay area called Bobcat Batteries. The owner was knowledgable and after explaining our system he grabbed two 100-amp hour ‘Intimidator’ AGM deep cycle batteries. They had previously been used but he checked their charge and assured us they had plenty of life left in them. He even included a limited warranty. We paid $200 for two 12-volt batteries with a total of 200 amp hours capacity. This is less than half the price of new batteries.
The AC Inverter
Our laptops, camera, drone, and portable speaker all require AC power to charge. We also thought that we might need AC power for a blender or other appliances that might be used occasionally. We chose a 1500 watt pure sine wave AC inverter from Cotek. This was the most expensive component in our system, costing us $499. Our inverter is powerful enough for appliances like microwaves, a conventional refrigerator, blender, or induction cook top. We’ve never exceeded the capacity of our inverter and it even shuts off automatically if you are not using any AC power.
The Nuts & Bolts of Van Solar
Beyond the panels, charge controller, batteries and inverter there are LOTS of other bits and pieces that make this system work. Fuses are important for a safe off-grid system. We have one installed between our batteries and another between our batteries and charge controller/inverter. We used wire from 2 AWG down to 14 AWG. Various connectors, crimping tools, electrical tape, zip ties and conduits hold everything together (more on these items in the future).
RV & Van Solar Resources
In future posts, I plan to provide more specific details about the components we chose and how I installed them. For now, here is a list of online resources I found very useful when designing and installing our system.
Knurlgnar24 on Youtube – off-grid electrical guru
- Knurlgnar24 (I couldn’t find his human name) is a super knowledgable guy who has MANY useful videos explaining things like how to crimp your own battery cables or selecting appropriate sized battery cables. Visit his YouTube page and soak in some knowledge.
Thoughts on our Solar Setup After Three Months Off-Grid
Our van solar system is performing better than expected. Everything has been operating smoothly with no faults in our wiring, no short-circuits and no burned fuses (yay!). Our panels generate more power than we need – by this I mean that during the day, when the sun is up, we can charge or use ANY electronics or appliances. Regardless of how much charging we have done during the day, our batteries have enough capacity to run our refrigerator and vent fan all night long without dropping below 50% capacity.
We had a good test of our van solar system storage capacity when one solar panel ripped off of our roof while driving (there were VERY strong cross winds). It took us three days to find the appropriate replacement part (a new MC4 connector) to get things functioning properly. During those three days, we were completely unable to charge. We left our refrigerator plugged into our system the entire time and our batteries powered it without dropping below 12.4 volts. Good design means things just worked!
In conclusion, our solar system has been a worthwhile investment, providing us energy independence. Learning what we needed to purchase the components and install them correctly was a significant time investment. However, the pay-off of having environmentally-friendly electricity to power all of our needs has been both liberating and empowering. Furthermore, we are supporting the solar industry as well as helping others like us move towards energy independence, an endeavor we fully believe in.
Please ask ANY questions you have about our system – we’re excited to share our knowledge!