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Marine grade solar

Mar 6, 2017
36
Bristol Corsair 24 Tampa
Hi again guys...
Thx a gazillion for all the AWESOME advise given to me from so many of you. The proyects materials are been purchased and I can't wsit to get home in Sept. to do this things and get in the water.

Now then... SOLAR POWER 100 WATTS panel marine grade.
Thats my next project material to get.
Im all eyes to read your suggestions and soak in the knowledge.
100 watts its gonna be over my needs but extra never hurts.

Thx again to all...
CRivera
 
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Likes: kloudie1
Jan 11, 2014
7,855
Sabre 362 113 Fair Haven, NY
Don't underestimate your solar needs. While a panel may be rated at 100 watts, it will seldom produce 100 watts for a variety of reasons, chief among them is the rating is based on testing in optimal conditions, i.e., the panel is oriented correctly, temperature is monitored, and sunlight is strong (not cloudy or overcast). In the article linked below, Nigel Calder estimates a solar panel can produce about 3 times its nominal rating, a 100 watt panel can produce about 300 watt houres a day.

As Calder points out, there are a number of factors that contribute to panel efficiency. Marketing hype aside, the solar industry is like the wild west, very few rules and lots of bull. Buying from a reputable dealer helps and cheap is cheap.

Don't skimp on the controller, it is a critical part of the system. You will want an MMPT controller which will improve the charging efficiency.

We have 2 150 watt Solara panels with separate controllers. While they have only been up and running for a short time, the output has yet to reach 150 watts. On a couple of days it reach the 140 watt range. Solara panels are noted for their high efficiency and we have typically exceeded 450 watt hours a day, usually making 500 to 600 watt hours per day per panel.

 
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Likes: sailingsoon
Dec 29, 2008
798
Treworgy 65' Custom Steel Pilothouse Staysail Ketch St. Croix, Virgin Islands
marine grade
I wouldn’t be too concerned about looking for that. We’ve had ours for 10 years, and no reference to “marine grade”. Frankly, I doubt that there really is such a thing. If there is, it probably isn’t worth the difference in cost. Ours has been through ocean passages , tropical storms, and hurricanes. Like a Timex, it keeps on ticking…
 
Mar 6, 2017
36
Bristol Corsair 24 Tampa
I wouldn’t be too concerned about looking for that. We’ve had ours for 10 years, and no reference to “marine grade”. Frankly, I doubt that there really is such a thing. If there is, it probably isn’t worth the difference in cost. Ours has been through ocean passages , tropical storms, and hurricanes. Like a Timex, it keeps on ticking…
Hi
Which brand name you did purchase?
 

CarlN

.
Jan 4, 2009
578
Ketch 55 Bristol, RI
Unfortunately, flexible solar panels rarely last more than 2 years on a boat. The output starts declining almost immediately and even after a year can be down 50%. Also, with all solar panels shade is your enemy. Even shading 5% of a panel can reduce it's charging watts to zero. Here's a video from Will Prowse on the issues with flexible panels:
 
May 7, 2012
969
Hunter e33 Maple Bay, BC
Unfortunately, flexible solar panels rarely last more than 2 years on a boat.
The video certainly sums up my experience with flexible solar panels. I installed my first flexible panel from a reputable manufacturer (made in Italy) in 2016. Over the past 5 years, I have had 5 panels replaced under warranty. This year the 5th panel paneled failed literally days after the warranty expired. The local distributor sent me a 6th panel from another manufacturer (made in the USA). One day this week, while alongside, it produced a Pmax of over 100%. I have just installed a 2nd flexible panel manufactured in China. I am a sucker for punishment but I like the optics of the flexible panel(s). However, it was only because of the warranty replacements that I stuck with them. If either of these fail in the next oh say 3 years, I will be designing a system for rigid panels.
My take away is: I am sold on solar panels and if you are insistent on installing flexible panel(s) purchase from a reputable manufacturer and preferably from a local distributor.
 
May 7, 2012
969
Hunter e33 Maple Bay, BC
3rd season with our Renogy flexible panels. No issues so far
Renogy is the manufacturer of the panel I recently installed so I hope I have the same result. I must ask though, how do you know you have no issues? I monitor my panels with Victron MPPT charge controllers. Fortunately they have a feature that allows me to monitor a 30 day history of various data. That in turn allowed me to track a slow degradation of output from my panels. When it dropped below the specified performance, back it went to the distributor who lab tested it and submitted a claim to the manufacturer on my behalf.
 
Jul 1, 2010
871
Seaward 25, Catalina 350 Erie, Pa
Testing is tough unless the bank is depleted enough to take all they can put out and the sun angle is maxed out no shading lots of sun etc. Then the pmax feature can tell you what the bank is capable of. I recently caught my 160 watt panel putting out 156 watts so that one's fine. The other 160 is paralleled with a 100. That arrangement will limit the 160 some. The 2 controllers are networked so trying to track degredation isn't as simple as it sounds. Our recent cruising trip included too many marina stays and unfortunately too much motor sailing for any testing to be done, but I have no concerns.
 
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Likes: Hello Below
Apr 8, 2011
471
Hunter 36 Deale, MD
Can't comment on your install sesmith, but I'm sure you're aware of the nuances of installing flexible panels, though a lot of folks are not. I've seen people post photos of their flexible solar panels, for example, installed over the bows of the bimini which constantly bends the panel. While they're flexible, they're not designed to have constant pressure across the panel and damage to those affected cells often occurs. They're also flexible only to a point, past which damage does occur. But mounted on bimini, securely sewn/zipped in, and rarely if ever moved - much less stepped on or had tools dropped on them - my (admittedly limited) experience has been pretty good. My Renogy 160 watt panel will put out 750 Wh on a really good day, though much less in my slip most of the time since its partially shaded.

I do have a couple of small hot spots I'm watching, though they haven't grown, and the output seems consistent over time. I haven't seen any of the other things to watch for - delamination, snail trails or internal corrosion - but do keep an eye out for it. And like you, I track output via a Victron controller. The fact that one panel no one knows is even there basically returns all the electricity my refrigeration takes out of the system is pretty cool. And the Renogy warranty makes me confident if I do have a failed/failing panel I'll get satisfaction. If I was a long distance cruiser I'd opt to have a frame built and put hard panels on there, but that's not our type of sailing (yet!).
 
Jul 1, 2010
871
Seaward 25, Catalina 350 Erie, Pa
Yeah, on ours I beefed up the bimini frame. We also added pockets under the bimini fabric to hold 3 battens under each of the 160 watt panels. These battens go up over the bow rail to better support the panels. Our canvas guy sewed zippers on the panels so they're zipped onto the bimini.
 

CarlN

.
Jan 4, 2009
578
Ketch 55 Bristol, RI
Flexible panels on boats seem to have much shorter lives in the south where they overheat more easily. I do know several people in the NorthEast whose panels have lasted 3+ years with still over 50% of rated watts. But those boats were also hauled all winter and the panels removed or covered. For flexible panels I have on the bimini, the dealer recommended that I attach a backing of twin wall polycarbonate panels (the stuff used in greenhouse walls) using 3M VHB double sided tape. This lets the panel bend just enough to follow the bimini bows but has no hard spots or repeated flexing. But again, this is a New England boat. Not sure it would help in Florida. Falken Design 36 in. x 72 in. x 1/4 in. Clear Twin Wall Polycarbonate Sheet-MW-CL-1-4/3672 - The Home Depot
 
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Likes: Rick D
Mar 6, 2017
36
Bristol Corsair 24 Tampa
Unfortunately, flexible solar panels rarely last more than 2 years on a boat. The output starts declining almost immediately and even after a year can be down 50%. Also, with all solar panels shade is your enemy. Even shading 5% of a panel can reduce it's charging watts to zero. Here's a video from Will Prowse on the issues with flexible panels:
GREAT information, thx a lot. I guess rigid would be a better choice. Thx. Any brand you recommend? and why?
 

CarlN

.
Jan 4, 2009
578
Ketch 55 Bristol, RI
I would go to one of the large alternative energy stores. AltE in Massachusetts has been around a long time. Almost all of the fixed panels are warranted for 25 years. A problem is that many are 400 watts which may be too large to fit. You can get a 12v or 24v panel. Use a controller like the Victron SmartSolar MPPT that can take 12v-48v input for a 12v bank. Buy Solar Panels - Solar Panels for Your Home, RV, Boat | altE