Solarizing your rig

Just completed short trip to Tennessee with Grandson (camping, business, road test)

I’m posting this in case anyone out there is interested in solarizing their rig. The aesthetics may not appeal to everyone (we each have our idea of what is cool and what is not) but my goal was functionality and the 1300 mile trip proved what worked and what didn’t. Actually the solar function worked perfectly but a new air mattress proved to be a huge let down..

I’ve thought about a solar panel for the 4runner for some time now but I had two challenges – where to mount it and how to mount it. The thought of drilling holes in my roof was out of the question – mounting the panel on my crossbars wasn’t appealing either as that takes up precious space for cargo stowage. So I put the idea aside for quite some time until recently when I came across magnetic mounts for small solar panels – I’m thinking that’s kind of a novel idea so I contacted the company (Cutting Edge Power) and was told that there was a serious back order going on - so back to the drawing board. Looking at their product it looked rather simple and easy to duplicate so that’s exactly what I did.

The next question was – is it going to work? I bought 4 brackets off Amazon then purchased 8 (200lb) fishing magnets. Enlarging the existing holes on the mounting brackets I fastened two magnets to each bracket then attached the magnets to a 100 watt solar panel. Then I (carefully) attached the solar panel to the center of the roof just forward of the leading edge of the front LFD Ruggedized crossbar. I ran the two solar cables under the rubber strip on the outside edge (passenger) of the roof then down the A pillar into the engine compartment where it connected to a small charge controller which supplies charging current to the auxiliary battery.

Then a short road test praying that the magnets were doing their job. Backed off the throttle at 60mph then returned home to check for movement of the panel – none. Still was nervous as I knew the upcoming Tennessee trip would no doubt have me averaging 70-80mph speeds. So for insurance I added a 500lb magnetic (sounds ridiculous) to the center leading edge of the panel. Additionally I added a wind deflector that I thought was going to be large enough to just go over the front of the solar panel – turns out it was just not large enough so not having time to order another I just installed it forward of the solar panel. It helped but was not ideal.

The solar panel functions beautifully charging the aux battery with voltages between 12.6 (no direct sunlight) to 14.4 with sunlight. The purpose of this setup is to provide enough power to maintain a 45qt refrigerator/freezer unit and it does this perfectly. The aux battery, through a special (electric vehicle) relay can be instantly connected to the main battery charging system by the throw of a toggle switch, which I rarely have to do but the option is there if needed.

Oh yeah, the magnets - they are awesome! Zero movement of the panel!!

Below are links to the parts I used:

Refrigerator/freezer (S249)

45 Quart(42 Liter) Portable Refrigerator Car Refrigerator with Compressor DC 12V/24 AC110/240Volt Freezer Fridge Refrigerator for Car,RV,Truck,SUV,Camping,Home.Grey

https://www.amazon.com/dp/B08V58121C?ref=ppx_yo2ov_dt_b_product_details&th=1

Wind Deflector ($36):

$39 [2024 Upgrade] ICBEAMER 35.6" Sunroof Wind Deflector, Universal Fit, Tinted Moonroof Visor, Reduces Noise, Rain, Wind; Dark Smoke, Smooth, Waterproof, Double-Sided Tape

https://www.amazon.com/gp/product/B07HCW634B?ie=UTF8&th=1

500lb fishing magnet ($19):

$15 DIYMAG Super Strong Neodymium Fishing Magnets, 500 LBS(227 KG) Pulling Force Rare Earth Magnet with Countersunk Hole Eyebolt Diameter 2.36"(60mm) for Retrieving in River and Magnetic Fishing

https://www.amazon.com/dp/B075WS4Y1Q?ref=ppx_yo2ov_dt_b_product_details&th=1

Solar connecting Cable ($17):

$17 iGreely 10 Feet 12 AWG Solar Extension Cable with Solar Panel Female and Male Connector Solar Panel Adapter 12 Gauge (10FT Red + 10FT Black)

https://www.amazon.com/dp/B08KZNTYP5?ref=ppx_yo2ov_dt_b_product_details&th=1

Aluminum Solar Mtg Brackets ($16):

Solar Panel Mounting Bracket Aluminum Solar Panel Z Brackets Roof Solar Panel Bracket for RV, Boat, Wall, Caravans, Yacht and Other Off Gird Installation, Set of 4 Units, Black

https://www.amazon.com/dp/B0876KV13M?ref=ppx_yo2ov_dt_b_product_details&th=1

100 Watt Solar Panel ($86):

$70 HQST 100 Watt 12V Monocrystalline Solar Panel High Efficiency Module PV Power for Battery Charging Boat, Caravan and Other Off Grid Applications 31.8 x 27.5 x 1.18 in (New Version)

https://www.amazon.com/dp/B08SVXMK3V?ref=ppx_yo2ov_dt_b_product_details&th=1

Solar 10 Amp MPPT Charge Controller ($43):

$40 Intelligent 10A MPPT Solar Charge Controller, Digital LCD Display + Temp Sensor, 10 Amp 12 Volt Solar Panel Regulator with MC4 Connector, Perfect for 12V AGM, Gel, Flooded, Lead-Acid, Lithium Battery

https://www.amazon.com/dp/B09W61YHH9?ref=ppx_yo2ov_dt_b_product_details&th=1

200lb Fishing Magnets – qty 8 ($104):

https://www.ebay.com/itm/192425783766

 

Very cool setup! Thanks for posting the details and thought process.

If you had to guess, how quickly is it taking charge when in indirect light, vs direct light.

What about on an overcast day, how much output do you think it can muster?

 

That’s awesome. Is your auxiliary battery hooked to your main one with a separator? Is your panel always actively charging your aux batt, even while driving?
I am a novice at solar stuff and have a simple DIY system.
I have a digital separator between my batteries but I was worried about pulling a solar charge into the aux battery while the alternator is charging the main one. I couldn’t find the answers when I put it on my truck so I have only connected my panels when the truck is not running for fear of cooking something. Am I being too cautious?
Edit: I reread and saw the toggle switch note. That is what I need!

 

So…while driving you toggle off the connection between the batteries, solar is charging the aux, alternator charges main. When the engine is off, toggle on the connection and solar will charge both batteries? I have questions! lol Thanks for the detail. This really kinda changes the way I am thinking about how my system operates.

 

Great idea!

 

It’s cool and all but I don’t really understand why you’d do it.

100 watt panel that cost $86 is going to be super basic and inefficient, especially paired with a low end controller. I’d bet in ideal conditions you’d pull maybe 30 watts, which in a 12 volt system is 2.5 amps… on the equivalent of a phone charger. That panel is unlikely to be wired in a way that it will produce much of anything at all when even partially shaded, and having it attached to the vehicle means you need to park in direct sunlight so that a fixed panel that’s aimed inefficiently for almost always can make some power that may not even offset the extra heat load of the vehicle baking in the sun. Plus the vehicle will charge it when driving anyway.

I know it seems like a good idea and you see panels on vehicles a lot, it looks cool but the science behind it typically just isn’t there. I’d advise you to remove the panel, lengthen the harness and use it not fixed. Park in the shade and put the panel in direct sunlight angled so it’s perpendicular to the sun’s position and continue to adjust as necessary.

 

Mine is a 200w system. I spent almost 5 months on the road camping a couple years back, including over a month in Key West. I had the panels connected to my auxiliary battery and to that I had a cheap Harbor Freight inverter. It ran my GeekAir fan, charged my phone and iPad, I surfed the web, played music and never had a problem with the battery getting low or worrying about my truck starting. The main thing was the fan because it got pretty hot, and it ran non stop and I stayed cool. Without the panels I would have been running my truck to charge the battery. So, I have to argue with you. My panels work great whether the science supports them or not.

 

Indirect (depending on cloud cover) 12.3-12.6 volts. Direct sunlight: 12.8-14.4 volts

Transition time depends on various factors but typically going from cloud cover to direct sunlight you'll notice the voltage begins to increase within seconds.

 

This is the relay I use to manage the batteries. Here's the link for it's source: https://www.evwest.com/catalog/product_info.php?cPath=2_13&products_id=273&osCsid=57fd12d64e642e1db0fb5b9b4aa468b0
($114)




Below is my homemade control center that monitors each battery - this is how I have it set up:
Toggle Switch 1 (TS1) controls front wifi camera
Toggle Switch 2 (TS2) controls cargo area air compressor
Toggle Switch 3 (TS3) controls battery relay

On a normal (mostly sunny) day the solar panel easily maintains the aux battery along with providing voltage to my refrigerator (1.8 amps) plus maintaining a charge on 2 LED flashlights, DeWalt 20 volt charger, a GB40 jump start battery pack, and a small emergency am/fm radio. From last week's camp out with my grandson I found that the aux battery would last throughout night with voltage dropping down to 11.5 volts - any less than that my 3K inverter (

BENNTOP 3000 Watt Pure sine Wave Inverter 12v DC to 110v/120v AC Car Power Inverter with 4 AC Outlets&USB Output, LED Display Power Converter for RV/Camping/RV-Peak Power 6000W(3000W-12V)

https://www.amazon.com/gp/product/B09L83913Y?ie=UTF8) will go offline until the source voltage goes back above 12.



If the sun is not cooperating (while driving) I simply toggle on the battery relay which allows the alternator to come into play for the aux battery circuit. Note: The 3000 watt pure sine-wave inverter only works off the aux battery, unless of course the relay is activated to get alternator power. All toggle switches have two sources of power: key-on pwr (up position) and direct battery power when switch is placed in bottom position (center is OFF).

The picture below is with vehicle parked under a canopy and engine is off. Left gauge is main battery - Right is aux. All switches centered to OFF.

If you have anymore questions feel free to ask. This system works and what I like most about it is the "magnets" work! Without the magnets to retain the solar panel I would have never done this due to my aversion to drilling holes in my 4runner.

 

Awesome! Thank you. This will require some study. I really appreciate you taking the time to write that up.

 

Glad to do it!