Solar panel for roof rack

Looking for some good ideas for a single solar panel that could mounted on my roof rack that would be capable of charging my ac200p. My roof rack area is 48"x 65" . The 35v minimum seems to be a little problematic for just 1 panel. New to this solar thing. The Ac200p is a cool thing though. Would rather charge with solar while driving as opposed to using my alternator. Thanks for any insight.

Your bigger problem than finding a single solar panel mounted on the roof (not angled) that will provide sufficient wattage to charge your AC200 in a satisfactory manner. I would count on about 40% of the rated watts available for any panel / panels roof mounted. You will received a max. of 100 watts if charging via your vehicle electrical system.

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Thanks for response. I realize its not the best scenario. Just wanted to be able to charge AC200p while the truck was either moving down the road or just sitting in the parking lot at work. Kind of just using the panel to top the generator off. I don’t think I will ever use the 2000 watt capacity in the overnight camping scenario. I would use my suitcase panels on site for the remainder of the day. Or shoreland charge if I had electric at a given site. In my research I cant find any single panel that would meet the requirements. It sounds like using your truck to charge might not be that good of an idea on a stock alternator. I’d rather make my coffee on my camp stove than use my electric percolator (which makes coffee about as good as a Diet Coke at 32.1) than replace my alternator. Thanks again, I’ll keep studying.

If you can find a single panel that puts out 35+ volts while charging and fits in the space, I would go ahead and try it. If you do go the car charging route, your alternator won’t mind the 10 amps it would be using to charge via the car charge option.

Both Renogy and HQST make 100 Watt 12V panels that measure 39.65" to 42.2" long and just under 20" wide. Could you mount these on your rack such that three of them would fit sideways along the long dimension of your rack and wire them in series?

I thought of this. Just looking for a easy out I guess, thanks for your response

I just completed a very similar setup on top of my AT Overland Atlas pop-up topper on my Ram Rebel. I used 2- 160 Watt semi-flexible by Holy Solar (purchased at an RV dealer). Each are rated for open circuit at out a maximum of 29.3 volts and 6 amps but typically generates a maximum of 24.8 volts and 3.5 amps. One may be enough in full direct sunlight but better to hook them up in series. Each measures 58 3/4 inches x 21 1/4 inches. Multiple ways to secure to the roof depending on whether or not you have an existing roof rack. As I am a new member here I cannot seem to upload photos but would be happy to discuss.

One solar panel will not beging charging if it will not produce 35 volts. The lower limit for acceptable voltage for charging to begin is 35 volts. The example you posted above for your panels do not meet than minimum in single configuration and your would have to have both connected in series for charging to occur. There is a little leeway below the stated 35 volts but from what you posted I am sure your panels will not allow charging in single configuration unless thay are outputting in excess of the stated specs.

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You are correct Scott. I do know that I have seen a video where the Bluetti allowed for a charge down to 29v so it might be possible. No doubt hooking 2 up in series would be more certain and better. On my system, each panel is 25-30 volts and they are hooked up in series…therefore 50-60 volts is sent to the Bluetti. These 2 panels should fit on his roof…see photo.

The voltage will also constantly fluctuate up and down while charging. Each time it drops below the threshold all charging will stop and then the charging will attempt to reset and begin again after 30 seconds. It is very likely you will get no charging with the fluctuation. The video you are referring to had the AC200 being fed a constant voltage from a power supply which did not fluctuate. I have also seen charging down to 30 volts with my steady power supply but a solar panel is a whole diff animal. The AC200 charge controller constantly fluctuates the voltage and amperage input for highest charge rate and this fluctuation is the reason you need to be at 35 volts

Good to know…thx Scott. At 50-60 volts with these hooked in series I’ve had no problems thus far.