After installing the dual-battery system I needed a way to keep it charged up when we’re not on the road. I looked at both wind turbines and solar options. Most turbine options need a mast of 20′ or (ideally) more to get them up and away from turbulence caused by the ground, nearby trees, rock outcroppings and the like. That mast needing a base and a support system of guy wires. The body usually has a heavy generator motor in it and the blades need careful installation and removal every time you raise or stow it. Considering the storage requirements of a 20′ long (or more) mast, the weight and the setup and take down process every time I wanted to use a turbine I decided instead on solar for my meager stationary electrical charging needs.
I first thought about permanently mounting a solar panel up on the roof rack but then decided that room constraints and the lack of angle adjustability would hinder the most efficient capture of sunlight. The next option was to come up with DIY option that was powerful and portable enough to meet my needs. Looking into panel and controller option was a dizzying experience. Which controller should I use with what panel(s)? PWM (Pulse Width Modulation) or MPPT (Maximum Power Point Tracking)? What gauge wire would be most efficient for a run of any particular size? How portable and durable would any contraption I concocted end up being? Then I saw the Renogy 100W Foldable Solar Suitcase.
Sure, it’s a little more expensive than buying all those parts separately but, it just works. Just like that I joined the solar revolution. Simply pull out the 20-some-odd pound system and unzip the semi-hard-sided case.
Then unlatch and unfold the two panels.
Pull out the two adjustable aluminum legs.
Finally attach the clips to your battery posts and that’s all there is to it.
In 30 seconds or so you’re making electricity. The instructions that come with it are minimal but I have since downloaded the pdf version and have been learning how to tweak the built-in 10A, PWM, Viewstar Charge Controller so it best suits my AGM (Absorbed Glass Mat) battery setup. In the future, if/when the PWM controller dies I can replace it with an MPPT controller if I so choose.
The wires from the controller were too short for my regular needs so I made do by attaching them to my old jump starting cables so I could get the panels away from the Tacoma and get more wiggle room with placement and angle. Plus I can park the Tacoma in available shade and still get the panels out in direct sunlight. Of course, when you add length to your wire run you lose voltage. Attaching 12′ of 10AWG jumper cables to the 10′ of 12AWG cable that came with the Renogy suitcase did cause a small but noticeable drop in the power the panels were sending to my secondary battery.
To remedy that I bought two sets of 16′, 6AWG jumper cables from Harbor Freight and modded them. On both sets I removed the clamps from one end and attached camlock-style welding cable connectors in their place. I then attached welding cable connectors to those pairs of clamps I previously removed. One of the cables is connected directly to the controller. If a 15′ run is all I need I attach one of the modified pairs of clamps to it via its welding cable connector and attach that directly to my secondary battery. If I need a longer run I connect both sets of cable by their welding cable connectors and now have a 30′ run. The increased gauge of wire has completely mitigated any drop in voltage due to cable length and in fact I see improved throughput since I made this modification. Next I’m going to make a pair of short attachments end that go from welding cable connectors to regular household 110V 3-prong connectors so I can use these cables as an extension cord if need be.
If and when the controller dies, the panels break or the whole system is stolen I will make my own “suitcase” with two 100 watt panels that I will connect together with piano hinge, buy a better MPPT controller and use the largest gauge wire that I can between all the connections. There are more efficient, more powerful and more expensive options for solar charging but for a quick, easy, confusion-free and portable solar system this is a notable solution and it continues to meet our needs.