Solar panels on a fiberglass roof

[william_k]

Hello again everyone... &nbsp;I am moving forward in the planning stages of my conversion and am seeking the groups advice regarding my solar setup.<br><br>The way I see it, there are two ways to go about it...<br><br>1) &nbsp;A roof mounted solar panel.<br><br>or&nbsp;<br><br>2) &nbsp;A flexible, portable solar panel/roll.<br><br>I need to power my 12.1" laptop, my fans (2), and my lighting. &nbsp;I'll be using two 6V golf cart batteries wired in series as my battery bank.<br><br>I've found a great deal on a 145W panel to go up on the roof and I've found a guy locally who will mount it using screws and&nbsp;sealant. &nbsp;Initially I was going to do it myself with 3M VHB tape.<br><br>My questions are:<br><br>1) &nbsp;<strong>Would you go with mounted panel up top on a van like this? Or a portable panel to roll out at camp sites?</strong><br>-and-<br>2) &nbsp;<strong>How would YOU mount a solar panel to this type of roof to keep it from blowing off?</strong><br><br>My roof has a curve to it and I am really worried about the panel acting like a kite at high speeds and just being blown right off the top. &nbsp;<img src="/images/boards/smilies/bawl.gif" class="emoticon bbc_img"><br><br>I'll attach a picture to illustrate this curve. &nbsp;Also, the roof is fairly high up there and not easy at all to access. &nbsp;Because of this, the flexible solar panels you can roll out seem to make sense, though I'd rather just have a panel on top that I don't have to worry about setting up/taking down, etc.<br><br>This is all brand new territory for me so I appreciate any advice from the pros out there.<br><br><strong>Thanks,</strong><br>William&nbsp;<br><br><img rel="lightbox" src="http://files.websitetoolbox.com/82529/1478316" class="bbc_img"><br><br><img rel="lightbox" src="http://files.websitetoolbox.com/82529/1476060" class="bbc_img"><br><br>

 

[Guest]

At our shop we screw it to the roof and use ether dicor so sicaflex to seal it. IMHO I would screw it down than have a portable unit , less likely to get stolen, and not having to set up and take down all the time.where as on the roof, install and forget.

 

[Willy]

&nbsp;I have mine permanently mounted on the roof.. but I didn't screw it down. I used 'L' angled aluminum and flexible adhesive to glue it to my fibreglass roof. The L-bracket runs the length of my solar panel and it ain't coming off.. been like that for near a year with no problems. ..Willy.

 

[wrcsixeight]

The roll out panels are pretty good in low light conditions. &nbsp;The Unisolar 68 watters are 9'4" x 15.5.<br><br>I installed one over the Crown of my fiberglass roof and hooked it in parallel with a kyocera 130 watt framed panel.<br><br>Your roof looks flatter then mine. &nbsp;The Unisolar on mine was not a perfect fit at the Crown, and I suspect I damaged a cell or 2 trying to peel the adhesive backing in hot temperatures and let my temper flare.<br><br>Many people use screws and sealant to hold a framed panel down. Getting a screw to penetrate the wood inside the fiberglass sandwich is desirable. &nbsp;On my particular roof design, I did not like how any screws would miss the areas where thicker plywood was sandwiched inside the fiberglass.<br><br>I have good fiberglass and woodworking skills so I made 4 aerodynamic feet out of plywood and fiberglassed 4 corners down to the roof. The panel can tilt 90 degrees toward either side of the Van and be removed without much effort. &nbsp;It has seen at least 110 mph on a downhill stretch on I-10 through West Texas.<br><br>

<br>That was when it was first installed, 5 years before the unisolar was added next to it.<br><br>Mine is a work Van too.<br><br>While I can empty the contents to carry 4x8 sheets of plywood, it is easier to carry them on my roof.<br><br>I made a couple extra removable footings to protect the panels from plywood.<br><br>Here are several sheets of plywood just over my panels.<br><br>

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[william_k]

Wow&nbsp;<a style="color: #000000; text-decoration: initial; white-space: nowrap;" href="/profile/1980243" rel="nofollow">wrcsixeight</a>, I love those panel mounts you made! &nbsp; That is some seriously nice work!<br><br>Myself, I don't have such skills and am leaning towards this mounting kit. &nbsp;I would use 3M VHB tape to mount it.<br><br><img rel="lightbox" src="http://ecx.images-amazon.com/images/I/51tsClsOghL._SL500_AA300_.jpg" class="bbc_img"><br><br>It's the<br><h1 class="parseasinTitle " style="font-family: Arial, Helvetica, sans-serif; font-size: 1.7em; font-weight: normal; margin-bottom: 0px; margin-top: 0px;"><span id="btAsinTitle">Instapark® ZJ-34W Universal Drill-free Solar Panel Rooftop Mount</span></h1><br>and it's on Amazon and Ebay, you can get the whole set for $30 shipped.<br><br>Anybody have any experience with it?&nbsp;

 

[william_k]

BTW, I am now strongly leaning towards roof mounting the panel. &nbsp;Now it's just a matter how to do it.<br><br>Glue/Tape vs. Screws/Sealant<br><br>

 

[bee]

<strong><a style="color: #000000; text-decoration: initial; white-space: nowrap;" href="/profile/1980243" rel="nofollow">wrcsixeight</a></strong>&nbsp;do you have any pics of the panel tilted, that looks pretty awesome.<br><br>I personally would make or buy a roof rack and then mount the panel between it.<br>Benefits include<br>Stealthier<br>gives a frame for mounting other items.<br>I would also create a second roof using the roof rack. Some kind of thin sheeting &nbsp;with an air gap underneath. &nbsp;This will shade your roof from the sun. &nbsp;An example can be seen here&nbsp;http://cheapgreenrvliving.com/Heat_Cold.html half way down the page.<br><br>Whatever kind of glue sealent etc that you use. Don't skimp and buy quality stuff. &nbsp;Also prep is important clean the area before applying for best results.

 

[wrcsixeight]

Bee,<br><br>Here is my Unisolar PVL-68 mounted next to my Framed Kyocera.<br>

<br><br>Here is the Kyocera being propped up by a foam cooler lid, and held from tilting further by a cord.<br>

<br><br>The pins that it rotates on when tilting are stainless steel Clevis pins. &nbsp;I used some aluminum angle and rivets to hold these pins tight inside the frame of the panel. &nbsp;They also re-enforce the corners of the panel as they join the corners more firmly.<br>&nbsp; This photo kind of shows the re-enforcement of the corners:<br>

<br>Note that doing this voided the panel's warranty. &nbsp;Painting the frame white would have voided the warranty too likely, but the white keeps the edges of the panel cooler than anodized aluminum and marginally increases output and also increases the stealth factor somewhat.<br><br>Most people are clueless I have 198 watts of solar on my roof.<br><br>I rarely tilt the panel as rarely do I need to. &nbsp;It does make it easier to access the junction box on this panel. I've upgraded the wiring since this photo, from 12 awg to 8 awg for this panel. &nbsp;The Unisolar has its own 10 awg run to the charge controller.<br><br>William K,<br><br>That mounting kit looks sweet. &nbsp;I would seriously have considered getting that if it were available in '07 and I were aware of it. &nbsp;Make sure you get any wax or oils off the roof before adhering the tape to it, if you do get it. &nbsp;If the roof has a Gelcoat instead of paint, make sure the gel coat is not cracked and easily able to be peeled from the fiberglass with some blue painters tape.<br><br>I sanded down through the gelcoat to bare fiberglass before adhering my plywood mounts to the roof, and then covered the wood with several layers of fiberglass Matt saturated with polyester resin.

 

[vantripper]

I have a dodge Ram Mark3 high top conversion & I have been leaning ( & researching) putting 3 self adhesive 68 watt unisolar flex panels On the roof. The measurements seem to work. That would give me a tad over 200 watts & to me, would seem stealthier & more theft resistant. I saw a you tube video that showed these flexing at some sharp angles. I don't think that you can damage a few cells. My thought is that it either works or it's broken. I don't think that you can break them just a little. This setup along with an 8D Lifeline Agm (255 amp)battery and a 20 amp Mppt controller should work,right? BTW,I really love this forum.
I also bought a water damaged popup camper for $100 from an Rv dealer. I took out all of the appliances, 3way fridge,sink,stove,locking dresser drawers, fire extinguisher ,etc. And left the rest. I know, I could have made a good trailer with the chassis, but I don't want or need a trailer for my (future) minimalist lifestyle. All that I need now is an under chassis propane tank and I can start building. I'M SO EXCITED!!

 

[vantripper]

This is the clip I saw. I'm not interested in that mounting system, just the flexibility.

 

[vantripper]

http://www.amazon.com/gp/aw/d/B00573ZADW/ref=mw_dp_img?is=l

 

[wrcsixeight]

The Unisolars will not lay perfectly flat over the double crown of the roof, where it tapers toward the front and side. &nbsp;They can bend, they cannot stretch. Where mine makes the downturn to the drivers side, there is a 3/4 bump at the crest on one side.<br><br>No way around it.<br><br>I filled it with caulk.<br>&nbsp;<br> These Unisolars do have good low light performance and partial shade tolerance.<br><br>When I first installed mine I was getting about 20% more out of it than it was rated for, they say this is normal for a few weeks.<br><br>The backing paper on mine was difficult to pull off which I attribute to doing it on a hot day in direct sunlight. &nbsp;Once peeling off the backing started, one could not stop. &nbsp;Otherwise the paper fused to the sticky butyl, and peeling off the paper had to be started from a different side. It couln not be restarted pulling in the same direction. &nbsp;By the time I was done, the neighborhood was black with curses and a thousand bits of small paper were floating around. &nbsp;Very frustrating, and at one point I had to peel some back off the roof which required huge amounts of force, which might have damaged a cell or 2 or the diodes between the cells, as I do not see as much output as I expect in certain conditions.<br><br>Be aware that PVL-68 uses mc3 connectors that exit behind the panel and 12 awg wire.<br> &nbsp;ePVL-68 uses MC4 connectors that exit off to the sides with 10 awg wire.<br><br>Mine is the MC3, and it is getting more difficult to get MC3 pre made wire. &nbsp;I got some 10 awg wire with Mc3 cables, and it has 7 strands, &nbsp;Not very flexible at all and made routing to my charge controller another tool throwing curse fest.<br><br>More options exist for mc4, which is locking connector with bigger contact surface for less resistance.

 

[Jennifer]

<span style="color: rgb(51, 51, 51); font-family: Verdana,Arial,Tahoma,Calibri,Geneva,sans-serif; font-size: 13px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: left; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; background-color: rgb(250, 250, 250); display: inline ! important; float: none;">I know a person who used 3M VHB tape to put his 60W panel on. After 3 years it is still there. It fact if you try to take the mount/tape off you will most likely pull the fiberglass off with it. Last year he mounted his second panel using the VHB tape and got the panel slightly off center but one the tape touches it is there forever. To me it seems like I have more flexibility long term if I go with screws. If I change panels and the mounting size changes the screw method would allow me to make the change. The VHB tape would not. So I am leaning to screw method. However, finding a professional in Texas to do the install is turning out to be a challenge.<br></span><em><a href="http://www.empyrealenergy.com.au/" rel="nofollow" target="_blank">Empyreal Energy</a></em>

 

[blars]

Mismatched panels will work, but not give you their rated power.&nbsp; Your old controller is probably PWM, an MPPT controller will give you more power from the same panels.

 

[ccbreder]

WRC 68 does some really nice work, and I thank you for sharing with all of us.<br>I read some marine sites about solar, and some have had problems with the flex panels. Maybe just some brands.<br>Solar panel output is lowered by higher temperatures, some air space under the panels help to cool.<br><br>