Adhesive advice for Solar panels

Aurelia · Posted: Wed May 11, 2016 12:03 pm Post subject:

The panels I used are basically one 12v type 100w cell assembly split longways in half to get two skinny panels.

I could not find an reasonably priced panel of similar dimensions with as many watts of output.

The advantages of this panel type over the rigid type is the ability to fit a curved surface (I did not need), the lower roof profile (I liked) and lower weight (I wanted). A 50W rigid panel typically weighs over 10 lbs and my 50w panels are less than half that weight for both panels.

As of this morning I have the wiring complete and running into the boat. I have a Kayaking trip starting tonight but plan to finish the install next week.

Thanks everyone for your thoughts and ideas.

Greg

thataway · Posted: Wed May 11, 2016 6:23 pm Post subject:

Greg,
Thanks for the photos and details--looking good and neat!. I want to see the numbers and see how these work for you The only reason I mentioned using a separate monitor, because you will probably get the "net" in / out with the Victron--vs a pure output with the separate cheap monitor. But you could also put a Digital volt meter in series, and get the output, since it will be less than 10 amps.

BrentB · Posted: Wed May 11, 2016 6:35 pm Post subject:

Nice job. It looks very sharp and professional

Marco Flamingo · Posted: Wed May 11, 2016 11:33 pm Post subject:

I just installed a flexible solar panel using 4 snads (Google it). Haven't done a photo album yet. The top of the CD 16 has a slight curve, so the thin flexible panel was the way to go. The snads put 1/4 air space under the panel. I was concerned about the panel blowing off, but now having installed it, I don't think I'd even worry when trailering (although I'll probably still remove it.) I found a 50W that fits perfectly on the little bump on the cabin top of the Cruiser. I still need to get my solar controller installed. Too many projects.

I've had the older style floppy flexible solar panel laying on the top of my yurt for over 10 years. Still works great. I had my doubts about "flexible".

I have some of extra"solar panel connectors" that have a gasket in them for exterior connections of panels. Interested? I can bring them to FH.

Mark

Pat Anderson · Posted: Thu May 12, 2016 9:37 am Post subject:

Looks good, Greg. Where is the controller and how are you bringing the cables?

SGIDave · Posted: Thu May 12, 2016 10:05 am Post subject:

Foggy · Posted: Mon Oct 24, 2016 6:03 pm Post subject:

Greg,

Well, you've had a summer with your solar panels.
How did they work out?

I am considering a couple Ganz semi-flexible panels (55W to 80W)
and have a few questions:

1. Did you wire your 2 panels in parallel or keep them separate?
(Reports say a parallel connection will draw down the non-shaded
panel output as well as the shaded panel; series wiring is worse)

2. What charge controller(s) did you use (PWM or MPPT)?

3. Are you distributing the solar charging to one or two batteries
or battery banks?
(If two, how unless your charge controller is capable of 2 banks?)

4. Did you wire directly to the battery(ies) or to another battery input?

5. What average daily amperage output are you getting from your 2
100W panels?

Aye.

Aurelia · Posted: Mon Oct 24, 2016 6:11 pm Post subject:

First, it looks like I never say Pats question so here is that one...

I ran the wiring along the back of the roof and into the corner of our canvas with a drip loop like the RADAR cable. The wires then follow the RADAR cable through a rubber grommet in Joes custom Bulkhead and into the cabin and forward to behind the helm. That part was easy and is hidden from view inside the boat.
Pic of wiring on roof here:

http://www.c-brats.com/modules.php?set_albumName=album2486&id=20160511_210616&op=modload&name=gallery&file=index&include=view_photo.php

Greg

Foggy · Posted: Mon Oct 24, 2016 7:36 pm Post subject:

Hey, that's great.

Can you please answer my questions?

Aye.

Aurelia · Posted: Mon Oct 24, 2016 7:44 pm Post subject:

I was working on them and teaching a class at the same time so it took a bit. Here they are.

1. Did you wire your 2 panels in parallel or keep them separate?
(Reports say a parallel connection will draw down the non-shaded
panel output as well as the shaded panel; series wiring is worse)

I had to wire them in series in this case because I used 6v panels. They were the only model of the type I could find that were sized perfectly for the short roof of the 19. There are impacts from shading of course but with total actual panel output near 19 volts, they can stand minor shading from my roof rails and still push a charge well enough.

2. What charge controller(s) did you use (PWM or MPPT)?

Because I already have a monitor, I choose to use a very simple PWM charge controller. Our setup is so small in Volts that the possible gains from a MPPT type don't exist. If you are using multiple panels and pushing well over 24v into a 12v system through a controller, the MPPT has advantages. I also liked the small size of this one for easy mounting in a tight location with only double stick tape.

http://www.campingworld.com/shopping/item/nature-power-solar-battery-charge-controllers-8-amp/56011

3. Are you distributing the solar charging to one or two batteries
or battery banks?
(If two, how unless your charge controller is capable of 2 banks?)

I have the controller wired directly to a buss bar connected to our house bank (two batteries in parallel) and that bank is linked to the start bank using a combiner that allows for two-way power flow. (http://www.yandina.com/c100InfoR3.htm) I have the start battery isolated from house loads so I don't really worry about pushing power back that way. I also carry a booster battery pack in case I/anyone needed a quick jump.

4. Did you wire directly to the battery(ies) or to another battery input?

The controller goes basically to the house batteries using a primary buss bar distribution point behind the helm (our house batteries are under the berth area)

5. What average daily amperage output are you getting from your 2
100W panels?

I have just the two 50w, 6v panels for a total of 50 watts for 12v charging. We seem to pull in 12-15AH of power for us in mixed summer weather and will charge at well over 4 amps when the actual sun comes out and just less than 1 amp in full cloudy conditions. We basically have a trickle charger on steroids connected all the time and that allows us to run the freezer and other accessories for up to 5 days without other charge sources before needing to move or plug in. This was our hope and is working great for our little boat.

Greg

Foggy · Posted: Mon Oct 24, 2016 8:59 pm Post subject:

Hey Greg,

Thank you! Very helpful comments.

Sorry if I came off terse. Not intended to interrupt you
teaching stuff.

Bravo on your multitasking.

Aye.

Larry H · Posted: Tue Oct 25, 2016 12:43 pm Post subject:

For installing a rigid panel I was referred to this company.
http://amsolar.com/

They have a mounting system they developed for RVs.

See the mounts here http://amsolar.com/rv-solar-panel-kit/mounting-accessories

For mounting instructions and YouTube video instructions, see here http://amsolar.com/diy-rv-solar-instructions/edmounts/

This looks like a good solution for mounting rigid panels. If it works on RV roofs, it should work on a C-Dory.

I have not tried this and I have not purchased anything from this company, but I like their ideas.

thataway · Posted: Tue Oct 25, 2016 1:41 pm Post subject:

I am using the "Z" mounts which Larry linked to on my RV. They seem to work fine--keep the panels off the surface of the roof to allow cooling.

One of the issues in any set of solar panels is tracking. You can get considerably more, power out, even if you manually turn the panels every 2 hours vs laying the panel flat on the roof. I have seen some C Dorys which have had 2 axis tracking. Folks who are living off the grid, have a timer, which will turn the panels continuously during the day--about once a week they change the Azimuth, as the sun declination changes with the season.

Studies show that 2 axis tracking will give about 35% more power output vs panels laid flat. Just raising the panels in the N/S plane to give the max azimuth, will increase the output about 15%. Considering the cost of panels that seems a reasonable thing to do. For trickle charging--not so important, as when trying to keep up with refrigation demands

Foggy · Posted: Tue Oct 25, 2016 5:04 pm Post subject:

The appeal solar panels have for me is they're quiet, out of the way and once
set up, hooked up and working no fussing and adjusting is 'necessary' (albeit
sacrificing some amperage output). There are plenty of others things to mess
around with.

C-Dory pilothouse roofing is not flat but bowed slightly port and starboard.
Considering my preference for fixing and forgetting about them, I'm going with
semi-flexible aluminum backed Ganz eco-energy, probably 2 55W panels with
a max output of 3.2 amps each. Easy to thru-bolt thru the roof decking with four
3/4" - 1 " small blocks of PVC or starboard and they bend to conform to the
curved pilothouse roof.

This set up puts each slightly curved panel central azimuth off vertical by
several degrees meaning to me one panel may have better alignment hence
better output than the other during the optimal daylight hours. It also
presents a dilemma as to having them connect
A) in parallel to one charge controller
or
B) separately with each panel having its own charge controller.

I've read with panels in parallel, the one panel with shade or less optimal solar
alignment will adversely affect the output of both panels WORSE than having
separate panels each doing their own thing as best they can.

Any informed opinions here with suggestions? I'm all ears.

Aye.

Aurelia · Posted: Tue Oct 25, 2016 7:20 pm Post subject:

With just those two panels, I would wire each to a small and simple charge controller so they can work as well as possible when sun is on them. When you have one side shaded or angled away from the sun, the other panel will not be compromised by it. With only two panels, you only have a max of 2 times 12v for charging and that means the benefit of a combined MPPT unit over two simple PMW units is debatable. You don't have the volts to divide and charge very far (enough multiples of 12+ volts).

If you had three fixed panels of 12v, I would likely go with MPPT because it could better manage a steady 2x12 out of a partially shaded 36v. Anything less than 24v is still just 12v for charging, and positions of the panels will compromise them anyway. The added cost is not worth it for just two but that is my opinion.

Greg