Looking for ideas on how to install solar on an 1987 Happy Van

[hoyttrac]

I have a 1987 Dodge Ram 250 Merry Miler Happy Van.  I plan on taking off the air conditioner and putting a fan in which will take off a good piece of weight.  I have 2 100 watt solar panels and would like to get 2 more so I have 400 watts but I am not sure how to put them on the van.  I have thought about trying to get a rack and install on that but there is an awning on the other side of the van so I wouldn't know how to attack a rack and haven't decided if I want to loose the awning.  

I have also thought about attaching them to the side opposite the awning but that would only allow me to charge when I am stopped and no charging from solar if I have to parking lot boondock at times.

I have thought of installing right on the high top, which of course is fiberglass but am concerned of the weight on a 31 year old topper. Each panel is just over 18 pounds.   Anyone have any ideas or suggestions?

 

[B and C]

I bought flexible solar panels and used industrial strength velcro to attach them to the roof. Cleaned both surfaces with alcohol before installing velcro. Still up there three years later and can be removed somewhat easily if needed. I ran two wires (they are in series) from them down the grey tank vent pipe to inside where I drilled two holes so they could exit the pipe.

I have two more flexible panels (in series) I can put out if I am parked in the shade. These two sets are paralleled before the controller. I use a 50 foot 10 gauge extension cord for the portable ones.

Your roof is strong enough, attaching solid panels would probably require drilling through the roof.

 

[Van-Tramp]

I have used 3M VHB tape to literally tape my three panels to the roof of the van. Only a few inches of tape will easily hold the panel, although do make sure you add some type of airdam on the leading edge to ensure driving speed winds do not get under the panels.

https://amzn.to/2RZIWK2

 

[hoyttrac]

I do appreciate the input.  Any suggestions on good but inexpensive flexible panels?

 

[B and C]

What panels do you have now? It is not good to mix and match panels. They should all have the same specifications.

 

[hoyttrac]

I have 2 Grape 100w solar panels.  They are definitely not flexible.  I have watched enough videos to know its not a good to mix em up.  I don't have those two attached yet.  Still have wire and mounting hardware to get in order to attempt to install those.  And so far I only have one house battery that I replaced in the camper van when I got it.  I had those panels a couple months before the old van was totalled due to getting a decent inexpensive price.  I have been slowly gathering pieces    I have approximately 7 months before I plan on hitting the road.  I will admit I am living in it now to help figure out what I may want to change or need to change before I start traveling.  I am mostly running off shore power and only using the house battery at this time for a light and the fridge when I can't be plugged in, since this is also my everyday driver.

 

[B and C]

If you are wanting flexible panels, You probably want to sell what you have and start fresh.

I have 4 - 100 watt windynation panels. Renogy wasn't selling them at the time. I see they now are stocking them again. The two I mounted on the roof I used industrial strength velcro with the shipping foam from the panels cut into one inch pieces and taped to the underside of the panel to "raise" it off the roof. This allows some air flow under the panels.

You really need to size your system for your expected loads and plan on a couple of rainy days with no charging.

 

[hoyttrac]

If I wind up going to flexible ones, I will certainly need to get rid of the non-flexible ones.  Thanks for your input.  I am looking into this so I can prepare.  Income isn't the highest to just do what I would like to.  And of course, the panel size will help determine what I can put on the roof.  I do know I would like to get up to 400 watts as I believe that will more than run what I plan on needing it for.

 

[B and C]

You will also need an appropriate sized battery bank. You will want to keep all the batteries the same size and age. Don't mix new ones in with old ones. Your first battery bank will be your learner set.

 

[highdesertranger]

you can mix the panels just use separate controllers. one controller for the ridged panels and one for the flexible panels. highdesertranger

 

[hoyttrac]

So i could concievably run 2 sets.  I will need to do some calculations on how well that will work with some of the things I want to run.  But it is an idea worth calculating for.  Thank you.

 

[Tom_M]

So i could concievably run 2 sets.  I will need to do some calculations on how well that will work with some of the things I want to run.  But it is an idea worth calculating for.  Thank you.

You don't mention what charge controller you will use. Your panels are most likely 12 volt so you have a couple of options. If you connect the panels in parallel, you can use a cheaper PWM controller. If you connect them in series which then gives you 24 volts, you will need an MPPT controller. One advantage of MPPT is it's more efficient and you will have less voltage loss from panels to controller. If you purchase two more panels that are the same as your existing ones you could connect all four in parallel or connect two sets of series connected panels in parallel. If your controller can handle the wattage you can get by with a single controller.

I have three 12 volt panels that are connected in parallel. All three are different wattage and go to a single controller. Two of the panels are attached to the side of my coach and are removable so I can park in the shade and set the panels in the sun. I don't know if this would be an option for you.

 

[B and C]

^^^Your losing a lot of potential with a mismatched set of wattages and panel types.

 

[Tom_M]

Granted the best option is to have identical panels. When connecting panels of different wattage in parallel the panel voltages should be the same. If the voltages are different the output voltage will tend to be pulled down to that of the panel with the lowest voltage. Typical Vmp ratings vary from about 17 to 20 volts. I don't recall the ratings of my panels, but the worst case scenario would be one 17 volt panel and two 20 volt panels. The result would be a 15% reduction in wattage of the two 20 volt panels.

The OP is considering identical panels so he should have no problems.

 

[highdesertranger]

I think y'all are misunderstanding me. it doesn't matter what voltage, type, wattage, or anything else. IF you run separate systems with their own controllers. run panels of one voltage say 20v on one controller and run other panels of say 40v on another controller, this will work fine it's done all the time. highdesertranger

 

[Tom_M]

I think you misunderstand what I'm saying. All three of my panels are 12 volt nominal. I agree that you can not mix 12 volt and 24 volt panels. Adding a 24 volt panel to a 12 volt system would reduce the wattage of the 24 volt panel by 50% if you do not run it through a MPPT controller.

 

[highdesertranger]

Tom I was referring to the original poster(OP) hoyttrac. if you have a separate question or problem you should start your own thread so as not to confuse us all. the OP wanted to know about mixing different types of panels. highdesertranger

 

[Tom_M]

I don't have a separate question or problem, at least about solar. To clarify (hopefully).

The OP currently has 2 panels and is considering adding 2 more of the same. He also is contemplating going with flexible panels and getting rid of the rigid ones. He never mentions mixing 12 and 24 volt panels.

I agree that if purchasing multiple panels they should be identical. I initially started with one panel then added a second and eventually a third. I agree that this is not ideal but it works for me.

Here's a good article on mixing panels:
https://solarpanelsvenue.com/mixing-solar-panels/