Anyone installed a slide out solar panel system mounted to the underside of their roof rack?

[alia176]

I'm looking for clever ideas that I can steal I don't like using ball bearings slides due to the dust/weather issue but let me see what you got. I may even incorporate a tilt feature just to increase the solar efficiency.

Thanks y'all.

 

[e9999]

Timely thread as I have been thinking about doing this for the last 10 years and it's time I get off my duff on the subject. Ironically, one basic issue is that a well-designed roofrack should ideally be very close to the roof I would think.

 

[alia176]

I've found some ideas on Expo and I may not have a choice but to go with the typical ball bearing slides. However, I'd like to figure out a way to telescope the thing in/out w/o using a drawer slides.

 

[george_tlc]

Well, it's not like you need precision rollers etc - it's just a solar panel...

So pipe would like work, a smaller diameter inside, with large diameter on the outside. Then it's just a friction slide. Thicker wall UV stabilized abs etc would work I'd think. Just needs to be thick enough to support the extended weight of the panel. Holes drilled through to pin open or closed.

Or recycle something like https://www.amazon.com/Adjustable-Telescoping-Aluminum-Tarp-Poles/dp/B072K1B91Q

Just need a way to clamp the vehicle end and the panel to the poles.

cheers,
george.

 

[carbon60]

Sub'd. I want. I think I want it to extend forward, over the windshield.

 

[alia176]

Well, it's not like you need precision rollers etc - it's just a solar panel...

So pipe would like work, a smaller diameter inside, with large diameter on the outside. Then it's just a friction slide. Thicker wall UV stabilized abs etc would work I'd think. Just needs to be thick enough to support the extended weight of the panel. Holes drilled through to pin open or closed.

Or recycle something like https://www.amazon.com/Adjustable-Telescoping-Aluminum-Tarp-Poles/dp/B072K1B91Q

Just need a way to clamp the vehicle end and the panel to the poles.

cheers,
george.

Yup, exactly - no precision rollers necessary. Just need to make sure that it can go out, maybe 1' away from the vehicle, and still be supported appropriately.

 

[LS1FJ40]

I did this. I’ll post a link...

 

[LS1FJ40]

Here it is the day I picked it up from @reevesci aka Trail Tailor on the way back from California.

A couple of things to learn from:

1) slide out solar panels rattle. Annoyingly so. Even with spring latches. A little electrical tape around the latch solved this.

2) use slides that are all metal or bolt them instead of welding them to the frame. You cannot powder coat with plastic/rubber inside the slides.

3) I ended up removing my slide and am rebuilding it to accommodate a bigger, 160w panel.

4) you have to figure out a way to have enough slack in your wiring in order to do so. The way I am going to do this is have all MC4 connections. I will have the wiring fit properly with it retracted then be able to quickly disconnect that and insert a leader made to the length needed when extended for when I get to camp. I will likely leave the leader in place as I move from place to place but then remove for highway speeds.

Let me know if you have any questions.

 

[alia176]

Nice pics, thanks dude. May I get a closeup or two of the sliders attaching to the rack floor please? Are you able to pull the panel all the way out and if so, how far past the leading edge of the rack?

 

[LS1FJ40]

It doesn’t slide out all the way past. You’d have the build bracket out in the front in order to do because it has to cantilever too far. It probably sits back about 6”.

 

[RFB]

Here it is the day I picked it up from @reevesci aka Trail Tailor on the way back from California.

A couple of things to learn from:

1) slide out solar panels rattle. Annoyingly so. Even with spring latches. A little electrical tape around the latch solved this.

2) use slides that are all metal or bolt them instead of welding them to the frame. You cannot powder coat with plastic/rubber inside the slides.

3) I ended up removing my slide and am rebuilding it to accommodate a bigger, 160w panel.

4) you have to figure out a way to have enough slack in your wiring in order to do so. The way I am going to do this is have all MC4 connections. I will have the wiring fit properly with it retracted then be able to quickly disconnect that and insert a leader made to the length needed when extended for when I get to camp. I will likely leave the leader in place as I move from place to place but then remove for highway speeds.

Let me know if you have any questions.

View attachment 1708555 View attachment 1708556 View attachment 1708557

Im using one of these leads from witsend for my solar panel thats going on top of RTT same idea though and will work prefectly. Im going up down your rolling in out easy peasy
Joey can give you one with no ends or use the anderson @nxlt

 

[LS1FJ40]

Im using one of these leads from witsend for my solar panel thats going on top of RTT same idea though and will work prefectly. Im going up down your rolling in out easy peasy
Joey can give you one with no ends or use the anderson @nxltView attachment 1708845

Yeah, he made me one with Anderson Powerpoles on it for my fridge. I don’t like the idea of it flopping around up on the roof. Unplugging and plugging in won’t be a big deal. Maybe I’ll have him make me one for when I am at camp and it only flops around between camps.

 

[RFB]

Yeah, he made me one with Anderson Powerpoles on it for my fridge. I don’t like the idea of it flopping around up on the roof. Unplugging and plugging in won’t be a big deal. Maybe I’ll have him make me one for when I am at camp and it only flops around between camps.

conduit clips 1/2 with plastic guards keep it squared away.

 

[alia176]

It doesn’t slide out all the way past. You’d have the build bracket out in the front in order to do because it has to cantilever too far. It probably sits back about 6”.

Ok, thanks for the confirm. But, I do have to wonder since the panel is getting shaded, are you getting anything out of the panel? I thought if a panel gets partial shading, then the whole thing produces near zero amps.

 

[LS1FJ40]

Ok, thanks for the confirm. But, I do have to wonder since the panel is getting shaded, are you getting anything out of the panel? I thought if a panel gets partial shading, then the whole thing produces near zero amps.

Nah, just reduces the efficiency.

 

[Cruiserdrew]

@alia176 , you're right of course. A partially shaded panel, means basically no output in real terms.

 

[LS1FJ40]

@alia176 , you're right of course. A partially shaded panel, means basically no output in real terms.

Define partially shaded...

 

[Cruiserdrew]

Here is a good example of partially shaded:

 

[Cruiserdrew]

The way panels are made, any partial shade, means the entire string of cells does not work. Bypass diodes try and get around this but really cannot. It's a silly and sloppy design to have a panel that remains partially shaded by the rack. Take that panel out and put it on top of the rack and it will work fine. Just don't expect anything as is. Seriously, it's like not having a panel at all. Measure your panel output and you will see the futility of what you are showing. That looks like an 80-100 watt panel and I'll bet your net is under 10 watts.

And @LS1FJ40 watch out. Ali is an EE with a huge installed solar system and knows perfectly well what solar panels do and don't do. I am not an EE but know perfectly well that your set up won't work as is.

 

[LS1FJ40]

Interesting, I’ve never measured it but have been able to power my fridge. My new 160w panel showed up today so hopefully I’ll have time this weekend to install. I’ll mount it on top of the rack to make sure.

Thanks for the insight.