Mouting Solar panels

[Kyhendrix]

Hello, I am in the process of adding solar panels to Windsong. I am looking at the panels that can either be glued down todeck or screwed down. I am wondering if anyone has a preference as to which way isbetter for long term? Also has anyone glued them down to their hatches?
Thank you

[Aquaria]

Am I right that you talk about flexible solar panels?
... glued down to the deck, you'll never know what happens underneath and it might be tricky to get them off again.
I'd prefer to screw them down using elastic filler to seal the screw holes.

And ever though about using solid solar panels? Their performance is better and srewed on frames that enable the ventilation from behind could be a good thing as solar panels reduce ther performance when they get hot.

Uwe
SY Aquaria

[Kyhendrix]

Looking at either sunware or ganz. I have thought about the solid ones quite a bit and just not sure if that is right way to go. Starting from scratch here.
Thanks for your input!

[Auzzee]

The problem with affixing flexible panels is the heat they accumulate. They will cook the deck and radiate a lot of heat into the cabin or space below. As pointed out by Aquaria in a previous post, higher temperature means reduced output. Also, they present a very slippery surface and will, assuming you are on a sailboat, spend a lot of their time under the shadow of the sails. No direct sunlight means negligible electricity production

Hard panels are a better option for all of the above reasons, plus they can provide shade for the helmsman when mounted on a frame above the stern, they are easier to maintain, are a little less expensive per watt and will last a lot longer. Also if you venture into the cooler lattitudes, they can on a frame, be angled toward the sun for much greater efficiency.

In truth, I would only use a floppy panel if I was in a very small boat where I needed to keep a single battery topped up.

[Kyhendrix]

Auzzie, it is a sailboat with center cockpit. The wife is stuck on these flex panels. She is afraid we will lose time with wind drag with winging them. I am not sold on either but was gonna place the hard panels along the stern and lifeline area. Will let her know on the heat buildup and production drop of electric. Maybe I can convince her otherwise. I wonder who will win here.
Thanks a bunch

[haiqu]

Most of what Auzzee has stated is FUD I'll have to say, sorry there mate. Atop a 12mm timber or 6mm f'glass deck there will be no noticeable change in internal temperature, and solid panels are slippery too if you're silly enough to walk on them.

In real world tests the flexible panels have been outperforming the solid ones regardless of shading effects. Del on Chiara Stella has been getting 9A output from a pair of 80W flexibles, I'm lucky to get that from four solid frame types totalling 340W. Our mounting positions are both partially shaded and we both use MPPT controllers. I'm still looking for other factors that might contribute to his "Stella" performance but so far haven't found any.

I have to agree about the cost though, they are 3X the price of the solid type on eBay. I also partially agree with your wife on windage issues, but the effects would be minimal unless you're sailing a very good racing yacht. Aesthetics would be the only minus on the framed panels, they do look ugly.

My choice would be to go with solid and mount them on the pushpit up high like most people do. Flexible mounts will be more of a problem than an asset, just mount them flat. That's where mine will be going eventually, right now they're just lying on the cabin roof under the furled mainsail.

Regardless of which panels you eventually buy, please don't use glued mounts. Hard to remove, and if not they may come unstuck when you least expect it.

[Auzzee]

FUD?

Having viewed a deck from which flexible panels have been removed after being stuck down I can catagorically say, they will accumulate enough heat to cook the paint off the deck. If you don't realise the effect of this product on the deck, try painting your deck with non slip containing sand or glass beads. The temperature of the cabin and more specifically, the cupboards directly below them will rise signficantly. This has several effects including a raised degree of discomfort in tropical latitudes and increased humidity in enclosed spaces which, as anyone with a steel or timber boat will understand, can cause deterioration within the spaces so affected.

When in direct contact with the deck, the heat in the panels will rise due to a lack of all round ventilation; this will reduce the output of the panels.

If you use flexible panels, they should be separated from the deck by a layer of air, however, nobody walks on slippery solar panels of any sort when they are mounted two metres above the deck. No prudent sailor will lay anything on the deck which may be dangerous in a seaway due to any reasons, including slipperiness.

Mounted behind the boom, the likelihood of shade across the panel is much less than if it were to be stuck on the deck; and the ability to angle the panels toward the sun is also a means of greatly increasing the effectiveness of this equipment. Shade versus sun has a major effect on the output of the panels. In other words, putting SOLAR panels where there is reduced solar radiation WILL negatively affect the output.

If you are having trouble getting 9amps from 340w of panels, you need to look at your installation. I have two old 80w fixed panels which provide over 9amps, as long as the glass faces are kept clean. Being the sparky type you are, I am sure you will have already checked this but for the record, take a quick gander at the gauge of your wiring and length of the cable run both between the controller and the panel output, as well as the gauge which links the panels together.

[Kyhendrix]

Haiqu and Auzzie, good to see both sides here. The panels we were looking at appear to have an alluminum base which to me should reflect a little bit of the heat back up. Still studying that one and am gonna make decision soon one way or another. When you walk across a hatch in the sun the are very hot. We were thinking of mounting some small panels there and maybe some bigger panels over the center cockpit. Anymore thoughts?
Cap'n B

[ParadiseParrot]

They wont reflect back they will just transfer the heat to the deck faster. Al is a great conductor