Our three original RV solar panels output a maximum of 375 watts. Switching from a standard RV refrigerator to a residential fridge meant that that wasn’t nearly enough to keep up.
When we upgraded our house batteries from AGMs to our new Xantrex eGEN Lithium battery, we saw a big improvement in our ability to boondock (dry camp without hookups) without running our generator. But having all of that capacity in our battery bank only made it even more evident that our solar system was inadequate. Sure… the lithium battery accepts a charge faster than the old AGMs, and provides many other benefits, so our meager system did better than before. But it wasn’t enough.
That’s why we upgraded our solar to a total of 8 panels putting out 1,300 watts! The new system is made up of two different types of panels, both from Xantrex:
- 4 x 160 Watt “traditional” rigid glass panels
- 4 x 165 Watt Xantrex Flex Max semi-rigid “peel-and-stick” panels
There were several reasons we chose Xantrex panels. For one thing, we love all of our current Xantrex equipment, so we decided it would be best to stick with a brand that had proven itself to us already, rather than piece together components from other manufacturers. Plus, the new panels offer advancements that aren’t commonly found in commercially-available panels today, bringing together several technologies that improve efficiency & durability. Those enhancements include:
- 5-busbars: Standard solar panels typically have between 2 and 4 busbars (the thicker metal conductors that you can see joining the cells together in a solar panel). Having more busbars increases the panel’s efficiency (electrons generated in the panel don’t have to travel as far to be “collected”) and its durability (any damage/breaks in the conductors means electrons can find another path more directly).
- PERC technology: This stands for Passive Emitter & Rear Conductor (or Passive Emitter & Rear Contact). Don’t ask us to explain exactly what that means… but we CAN tell you why it’s good! ???? It’s another technology that boosts the efficiency of the cells in the panel. That means Xantrex panels can generate the same amount of power in less space… and the rigid panels reach 18% efficiency (the highest available for mass-market, commercially-available solar panels).
- ETFE top layer: This is a feature of Xantrex’s flexible panels (standard AND Flex Max versions). It’s a more-durable coating than is typically used on semi-rigid panels (which should extend the flex panels’ useable life… “cheaper” panels are prone to scratching/etching/staining that reduces their output). This layer also offers better light-transmittance than standard coatings, meaning the Xantrex panels can generate more power from the light they’re exposed to… especially in low-light conditions (think early/late in the day and on cloudy days).
- Mesh Grid conductors: This is a feature of the Flex Max panels. If you look at them closely, you’ll see a fine mesh of conductors radiating out from the larger busbars. Again, this mesh provides two benefits: greater efficiency (shorter electron path) and improved durability (breaks/cracks in the conductors don’t prevent parts of the cell from generating power as much as standard wiring configurations would).
- Build quality: The Flex Max panels are an incredibly solid and sturdy design… far more robust than any flexible panels we’ve ever seen.
During the planning phase of the project, we talked quite a bit with our friend Brian of RVwithTito. He’s done quite a number of solar projects over the years, and it was great to be able to bounce ideas off of him and validate our plan. Plus we also got a lot of input from our friend and co-host on The RVers, Tom of Mortons on the Move. As an electrical engineer with lots of experience planning & installing his own solar array, his input was invaluable. When it was time to actually do the work, Brian even came over to help (and provide moral support)! Thanks to you both, Brian & Tom!
We have the 8 panels wired into two groups of four (4 x rigid and 4 x flexible), with the panels of each group wired in series (positive-to-negative, which adds up the voltage from each panel, while the amperage output of the array is equal to a single panel). Each series of panels is then wired (via 6-gauge, heavy-duty cables run from the roof) through a circuit breaker to their own MPPT charge controller. This arrangement allows each controller to maximize the output from each series of panels. It wouldn’t be as important if all of the panels were laying flat on the roof. But because our rigid panels are mounted on SolaRVector lift kits, they can be tilted to point more directly at the sun during the winter months, when the sun stays lower on the horizon. As a result, the two sets of panels (one tilted, one flat on the roof) can perform at their best. Had we wired the two sets of panels to a single charge controller that controller (A) would have had to be large enough to handle the output of all 8 panels and (B) would have had a hard time finding an optimal operating voltage for panels that are seeing such dramatically different levels of sun.
We’re thrilled at how well the entire system works. Even in December, during the shortest days of the year when the sun stays low along the horizon, our battery reaches 100% before the end of the day. And that’s with our residential refrigerator running, and both of us busy on our laptops (these videos don’t edit themselves, LOL!). Of course, if there are a few cloudy/rainy days in a row, we still end up running the generator. But, luckily, we don’t see many of those in the desert southwest! ????
Read more about Xantrex’s solar gear here: http://www.xantrex.com/power-products/solar/overview.aspx
Check out more details about our cool, remote-controlled lift kits from SolaRVector here: https://www.solarvector.net
And, of course, head on over to Brian and Tom’s websites to see what great stuff they have going on:
- Brian: RVwithTito.com
- Tom: MortonsOnTheMove.com
Featured & Related Products:
- Xantrex 160W Rigid Solar Panel
- Xantrex 165W Flex Max Solar Panel
- Conext MPPT 60-150 Charge Controller
- SolarVector Solar Lift Kits
- Duplex 6-gauge Cable (from panels to solar charge controller)
- Duplex 10-gauge Cable (power for SolaRVector kits)
- Liquid Tight Strain Relief for 6-gauge Cable (single opening… from AM Solar)
- Liquid Tight Strain Relief for 2 x 10-gauge Cable (two cable openings per unit… from AM Solar)
- Liquid Tight Strain Relief for 10-gauge Cable (single opening… from AM Solar)
- Waterproof IP67 Junction Box
- Dinkle Modular Solar Combiner (DK10N)
- Blue Sea 187 Series 30-amp Breakers (inline between panels & solar charge controllers)
- 40-amp in-line fuses (inline between solar charge controllers & battery)
- Cable crimping tool (for attaching lugs to 6-gauge cable)
- 6-gauge Cable Lugs
- Heat-shrink tubing
- MC-4 Connectors
- MC-4 Crimping tool
- MC-4 Wrenches
- 3M VHB Tape (0.75″ x 5 yards)
- Dicor self-leveling lap sealant
Recent & Related Videos:
- Overview Of Our Original Solar Setup
- Solar Panel Tilting — How Much Difference Does it Make?
- Solar Maximus! Optimizing the Sun When RV Boondocking
- LIVE from LAX! Upcoming Appearances & Video Update
- 2019 Wrap Up & 2020 Preview — Appearances, Discounts & More!
- RV Lithium/AGM Battery & Electrical System Upgrade — Part 1 — Project Intro
- RV Lithium/AGM Battery& Electrical System Upgrade — Part 2 — Battery Tray Expansion
- RV Lithium/AGM Battery & Electrical System Upgrade — Part 3 — Cord Reel Removal
- RV Lithium/AGM Battery & Electrical System Upgrade — Part 4 — Lithium Battery Installation
- RV Lithium/AGM Battery & Electrical System Upgrade — Part 5 — Power Cord Reel Installation
- SYSTEM UPDATE! RV Lithium/AGM Battery & Electrical System Upgrade
- Ultimate RV Electrical System Protection — Hughes Autoformer & Power Watchdog
- How to Run 2 RV Air Conditioners At 30-amp Campsites
Michelle M. Luck
Monday 21st of March 2022
I'm not sure if you'll see this or not but I'm going to ask anyway, just in case. Forgive me if. it's mentioned and I missed it, I'm literally getting cross-eyed from all the reading. Are you still using the Xantrex 3000 inverter with all those panels and the 600 ah Lithium battery? I love your set up and want to see if I can duplicate it but, in my case, I'll have to do it piecemeal over time. I DO need a new inverter (and batteries) so... what inverter are you currently using? Thanks in advance.
Monday 21st of March 2022
Hi Michelle... we're still using our Xantrex Freedom SW 3000-watt pure sine inverter/charger with our system. Works great!
Monday 8th of March 2021
Now that you've had them for a very long time, how have the flexible panels held up? Internet forums have proven a complete waste of time trying to find current information on current products. They look like a great solution, but issues with heat dissipation and so on keep coming up, and I don't want to damage my RV TPO (rubberish) roof.
Tuesday 9th of March 2021
Hi David! We love our flexible panels. They were easy to install, do a great job of putting out power, and are holding up just fine so far. No complaints. That said, we do have the advantage of a fiberglass roof, and we don't know what challenges might exist if you ever wanted to remove them (we generally don't think about that when we're installing a great new piece of gear)! But the adhesive on the back of the panels does indeed seem very strong. So while they'll surely stay down once put down, removal from a TPO roof might be a real challenge. We haven't seen any obvious signs of excessive heat transfer, but our roof is very well insulated, so we probably wouldn't notice. If light weight, ease of installation, and lack of holes into the roof are priorities for you, these panels are great. But they may have drawbacks compared to rigid panels, including more heat transfer, potentially permanent adhesion, and inability to tilt.
Sunday 30th of August 2020
Friday 10th of July 2020
Thanks for all the detail and the recommendation of installing the MPPT controller. It looks like you used the Schneider Electric Conext MPPT 60 PV Solar Charge Controller and not the Xantrex MPPT 30 Controller. Is this correct? Where did you place the charge controllers on your coach?
Friday 10th of July 2020
Hi Mike! We went with the Schneider Electric MPPT controller for 2 reasons:At the time we did our install, Xantrex didn't offer the current MPPT 30 controller. They only had a 30-amp PWM unit. Since we wanted to wire each group of 4 panels in series... we couldn't use that controller. The currently-available 30-amp MPPT controller isn't large enough to handle 4 x 165W panels in series. It can handle up to 3 panels no problem... but the fourth puts the output over it's 30-amp capacity. Particularly on the rigid panels when they're tilted (we've seen upwards of 50-amps of output from the Conext MPPT controller on the rigid panels). It wouldn't be that much loss on the Flex panels (likely just a couple of amps during the peak of the day), but with a system this size, why have ANY unnecessary loss?
Our charge controllers are in two different locations. One is mounted in our electrical compartment... because that's where the factory-installed (though upgraded to 6-gauge) solar wiring terminated. We brought the second run of 6-gauge wiring for the other series of panels down into the basement near our inverter/charger... and mounted the second charge controller to the chassis rails there.
Hope this helps!
P.S... if you're planning to wire your panels in parallel (more shade tolerant), the difference between MPPT and PWM controllers is less important.
Wednesday 29th of April 2020
You've now had the SolaRVector system for several months. How many miles have you logged since the install and have you experienced any issues since the install?
Wednesday 29th of April 2020
Hi Steve. Good question... we did our usual snowbird travel this year with them installed, so we covered about 5,000 miles (give or take). No issues whatsoever with the SolaRVectors... other than the fact that they can't prevent clouds! ???? LOL!