Solar panel placement

[donks2]

Hi All,

I'm in the midst of designing our solar set up for our 2001 Hawk. I'm looking at panels and the roof space I have. I'm wondering how important is it to center the weight of the panels side to side (two at 16 lbs each), or can I run them off center next to the the vents.

So, I can either center the weight side to side with more weight on the front of the roof, by mounting one panel between the vents and one in front of the front vent. Or center the weight front to back, by mounting them long ways alongside the vents, with more weight on the passenger side. Thoughts? Experience in how this changes the lifting? We are going to put external lift 'thingies' on, we use the speaker stand now, but adding 30+ lbs, I think the extra oomph will be a big help!

Thanks for you thoughts!

 

[DavidGraves]

Hi

Fill an old pillowcase or plastic bag with approximate number of pounds and put it up on the roof and then lift it....gives a good sense of what you will be lifting after the install.

Are you thinking of some sort of flex panels ? 16 lbs is pretty light.

DG

 

[donks2]

Hi

Fill an old pillowcase or plastic bag with approximate number of pounds and put it up on the roof and then lift it....gives a good sense of what you will be lifting after the install.

Are you thinking of some sort of flex panels ? 16 lbs is pretty light.

DG

Hi DG,
I'm looking at the Renogy 100w panels x 2 so it will be around 30+lbs.

 

[Vic Harder]

I have my 265W panel mounted at the very front of the camper. Makes lifting it significantly harder than the back. Keeping them away from shade producing vent covers is more important that weight considerations. The speaker lift you have can handle it.

 

[larryqp]

One thought
I had yakima roof rails installed the full length of the roof. Mainly to be able to carry a canoe now and then. The yakima cross rails have lockable quick mount brackets so the cross rails are removed if not carrying a boat.

When I mounted my solar panel I used additional "A Nuts" purchased online from eTrailer.com to mount the solar panel brackets. Worked great and it has not only allowed me to fine tune the weight distribution by sliding the panels forward or back, but I also mounted metal tie downs on the rails. We have used the tie downs to carry extra stuff in a waterproof bills bags now and again. I don't lift the roof with the canoe or extra bag attached.

Anyway, something to think about, just don't exceed the 100lb carrying capacity of the roof. My canoe weighs 40lbs, the racks about 7lbs, so it gives me a pretty good margin.

There is a post on this site about mounting the rails, but I had mine done by Rocky Mountain Four Wheel

I also had the 40lb exterior struts installed, but I'm a geezer, LOL

Good luck

 

[donks2]

I have my 265W panel mounted at the very front of the camper. Makes lifting it significantly harder than the back. Keeping them away from shade producing vent covers is more important that weight considerations. The speaker lift you have can handle it.

Thanks, Vic. Do you have any thoughts about one large panel vs two smaller ones? Of course, space issues, but in terms of how much power is produced, if the watts are equal? And we've decided to add the exterior struts, the speaker stand works great, but it did malfunction on our last trip, and that was a bit scary! with an extra 30-40 lbs up there, we're going for the assist!

 

[donks2]

One thought
I had yakima roof rails installed the full length of the roof. Mainly to be able to carry a canoe now and then. The yakima cross rails have lockable quick mount brackets so the cross rails are removed if not carrying a boat.

When I mounted my solar panel I used additional "A Nuts" purchased online from eTrailer.com to mount the solar panel brackets. Worked great and it has not only allowed me to fine tune the weight distribution by sliding the panels forward or back, but I also mounted metal tie downs on the rails. We have used the tie downs to carry extra stuff in a waterproof bills bags now and again. I don't lift the roof with the canoe or extra bag attached.

Anyway, something to think about, just don't exceed the 100lb carrying capacity of the roof. My canoe weighs 40lbs, the racks about 7lbs, so it gives me a pretty good margin.

There is a post on this site about mounting the rails, but I had mine done by Rocky Mountain Four Wheel

I also had the 40lb exterior struts installed, but I'm a geezer, LOL

Good luck

Ha, yep, get the geezer thing, we are going for the struts! Thanks for the idea about the rails. I thought about them, but couldn't really see the use, but you bring up a great point about fine tuning, and being able carry something else up there if needed. Off to search for that thread on rail install. Cheers!

 

[Vic Harder]

Thanks, Vic. Do you have any thoughts about one large panel vs two smaller ones? Of course, space issues, but in terms of how much power is produced, if the watts are equal? And we've decided to add the exterior struts, the speaker stand works great, but it did malfunction on our last trip, and that was a bit scary! with an extra 30-40 lbs up there, we're going for the assist!

I'd use the biggest you can get to fit, that will usually not be shaded by anything. Two or more on the roof raises serial/parallel questions. Higher wattage panels are typically also not "12v" nominal panels, meaning you will need an MPPT controller like the Victron line I have been touting, not a PWM controller. Better way to go anyway, but good to know now.

I have 40# struts and my wife can get the roof up (she crawls on the counter and uses her back instead of legs/arms). I nearly died last May, and struggled during my recovery with the roof. No problem again now ... whew!

 

[donks2]

I'd use the biggest you can get to fit, that will usually not be shaded by anything. Two or more on the roof raises serial/parallel questions. Higher wattage panels are typically also not "12v" nominal panels, meaning you will need an MPPT controller like the Victron line I have been touting, not a PWM controller. Better way to go anyway, but good to know now.

I have 40# struts and my wife can get the roof up (she crawls on the counter and uses her back instead of legs/arms). I nearly died last May, and struggled during my recovery with the roof. No problem again now ... whew!

Ok, so if I go with the the higher v panel, and a MPPT controller (which I've already decided on, not a specific one, but know I'll use MPPT), could a 12 v portable be used too? Seems a no brainer to go parallel on multi panels, but maybe I'm missing something. Like a few brain cells from the sizzling this solar learning curve is producing!

 

[Vic Harder]

Short answer, yes... Longer answer, it depends. Will your portable have it's own controller? That makes it easy. I installed 2 Victron MPPT controller to be able to handle roof and portable so I could make my own 200w portable setup.

If not, the wiring is a bit more complex, to bring the portable into a serial arrangement with the rooftop panel.

 

[donks2]

Short answer, yes... Longer answer, it depends. Will your portable have it's own controller? That makes it easy. I installed 2 Victron MPPT controller to be able to handle roof and portable so I could make my own 200w portable setup.

If not, the wiring is a bit more complex, to bring the portable into a serial arrangement with the rooftop panel.

Haha, it depends! I was wondering about the issue of whether to get a portable with a controller or not. So if the portable does have its own controller, then it's ok to just clip it to the battery and add an outside plug? And the roof system on the MPPT would just operate on its own, and the two controllers (I believe the portables are a PWM controller) can coexist and keep the battery healthy? Seems too simple and too good to be true with all I'm learning about solar

 

[Vic Harder]

"just clip it to the battery" is perhaps over-simplified, but ... yes. Ideally, you will have:

1) Solar panel(s) on the roof. They are there and just work when they can.
2) Roof solar will be wired to your MPPT controller and thus to your house batteries
3) Internal wiring leading to a plug on the outside of your camper. Use 12g wires... not 14 or smaller. This is a direct (except for a fuse!) connection between the portable panels and your house batteries
4) Portable panel(s) with controller. I have 100' of wire for my portables, so went with MPPT for those as well to reduce power loss over such a long distance. If you are using shorter cables to your portables, that might not be as critical.
5) Battery monitor so you can keep an eye on what's going on with all this charging stuff
6) A glass of your fave beverage when it all works for the first time!

 

[donks2]

"just clip it to the battery" is perhaps over-simplified, but ... yes. Ideally, you will have:

1) Solar panel(s) on the roof. They are there and just work when they can.
2) Roof solar will be wired to your MPPT controller and thus to your house batteries
3) Internal wiring leading to a plug on the outside of your camper. Use 12g wires... not 14 or smaller. This is a direct (except for a fuse!) connection between the portable panels and your house batteries
4) Portable panel(s) with controller. I have 100' of wire for my portables, so went with MPPT for those as well to reduce power loss over such a long distance. If you are using shorter cables to your portables, that might not be as critical.
5) Battery monitor so you can keep an eye on what's going on with all this charging stuff
6) A glass of your fave beverage when it all works for the first time!

Ok, thanks for answering that question about the two controllers working for the separate systems. My plan is to wire the battery to an external plug for the suitcase, the 'clip' comment is in reference to the clips that are included with the suitcase, but I'll do something more secure and permanent. And I DO need a glass of adult beverage, this can make my head spin!