Mounting Flexible Solar Panels on Bimini

[felizcortez]

I just had a bimini and dodger installed on the boat and am looking at installing flexible solar panels on top of each. I've attached a diagram for reference, but had a few questions.

1. Should the panels be mounted lengthwise so that they run on top of the bows or should they be mounted so they run port to starboard and avoid sitting over the bows?

2. Any particular panel manufacturers people prefer for the flexible ones. I'm trying to figure out sizes that will fit either in the lengthwise or horizontal positions to maximize output. So far it looks like most flexible panels are in the 100-150 watt range.

3. I thought about installing hard panels, but that will require more stainless steel work and I don't think it will look good.

4. Our house bank will be about 470Ah - 4x 6V Golf Card 235Ah batteries. We will be cruising the Sea of Cortez so what would be a good amount of output to charge amount of battery capacity.

[Kenomac]

Avoid overlaping the stainless supports and make sure they are attached on all four sides by zippers and or zelcro.

[Stu Jackson]

Don't know if you've seen this:


https://marinehowto.com/installing-a...e-solar-panel/

[john61ct]

You are aware that you may need to replace them much more frequently than framed ones?

Even installed properly I reckon 3 years average.

[john007]

I tried putting flexi units length wise over the bimini fabrique with stainless tube supports between the bimini frame. It was suggested and I followed the idea of marine ply panels clipped and screwed to the frame. Prior to fitting the panels I covered them in GRP tissue to avoid the need for varnish etc. They have been installed for several years and have not been any problem at all. I have two 100 watt panels which, whilst not at right angles to the sun, get all of the sun that is going.

[Paul L]

Fore aft mounting is usually better for shadow reduction.
We use aluminium backed flex panels. They deal with the flex of biminis better. You need to make sure the corners are covered to avoid chafe.
The amount of solar you need really depends on your usage and charging patterns. Extra is good if you have the space.

[john007]

The two 100 watts on the bimini are joined by two 50 watts flex panels on either side of the coach roof and a single 100 watt over the forward cover of the sliding hatch. 400 watts has proved capable of running all the standard equipment plus the fridge left on all night.

[alamoana]

My experience with flexible panels was a disaster. They worked great for a week or a month; no more than that. Either the bending by the wind on the Bimini or the heat when placed flat on deck destroyed them in little time. I went as far as making a rigid panel pout of a flexible one with plywood but they just do not last. I guess that is why they are so cheap. I have just converted to rigid ones an although too soon to tell, output is much greater. Good luck

[john007]

I agree that the flexi are not as robust as the rigid. I have had to pierce the plastic layer, both deck panels, and solder in a short length wire to bridge the break. Plenty of varnish to protect the mend. My bimini panels are fixed to 8 mm ply and to date have withstood many high winds the the winds of the Tranmontan can deliver, south of France.

[thinwater]

I'm going on 5 years with a cheap semi-flexible panel, but I mounted it to a deck so that it does not flex. It's still close to rated output.


The thing is they use the SAME cells as rigid panels, so you can flex them slightly for installation, but continued flexing is a problem. TANSTAFL.

[Miker1944]

We have had two Solbian flex panels attached to our Bimini for over 5 years and had no issues whatsoever. The 125 watt panels are attached parallel to the bows with Velcro along the forward and aft edges. We have been in sustained 60 knot winds twice during that period and never a problem with lifting. These two panels keep our batteries charged while running our refrigeration 24/7 and making water on an as necessary basis.

[Achab65]

Originally Posted by john61ct

You are aware that you may need to replace them much more frequently than framed ones?

Even installed properly I reckon 3 years average.

Originally Posted by alamoana

My experience with flexible panels was a disaster. They worked great for a week or a month; no more than that. Either the bending by the wind on the Bimini or the heat when placed flat on deck destroyed them in little time. I went as far as making a rigid panel pout of a flexible one with plywood but they just do not last. I guess that is why they are so cheap. I have just converted to rigid ones an although too soon to tell, output is much greater. Good luck

I am since 10 years in solar (8 years spent in a large factory producing pv panels).
PV cells (and therefore PV panels) are flexible as a crystal glass can be flexibly. You may not see that since the cells are encapsulated in the "sandwich", but everytime you bend the module you induce some "cracks" that can be more or less severe. In any case they will give reliability problems due to the fact there is an electrical discontinuity in the circuit (same as a wire with a strong bending reducing the size).
I understand flexible panels are lighter, easier to install, avoiding steel rollbars, etc but expecially if you handle them often, a flexible module can not guarantee a long life.
Not to mention the ones they claim you may walk on...

[Peregrine1983]

I have a similar setup and have had zero issues. I'm at the end of year 2 with these Windy Nation flex panels on my bimini: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I have them tied together and onto the bimini frame with paracord and I glued on little rubber "feet" to cover the corners to cut down on chafe. Our boat lives on a mooring. I removed them once for a named storm.

They produce plenty to charge my house bank of 4 golf cart batts, my start batt, and my windlass batt. We have a 42' (nearly) all LED ketch. No fridge. Two bilge pumps. 2500w inverter to charge laptop, and some misc items. Maybe they'll die and/or completely go to crap next year, but I've been very happy. Even with shading from my sailcover they seem to produce good juice and even in cloudy weather. I use a Victron MPPT controller.

This is the best shot I have. There's another one on the port side.

Good luck!

Edit: I used nice, thick wire for my runs. I forget the gauge... maybe 10, but I believe this helps a lot.

[john007]

It is good to hear of a success story. Your arrangement looks similar to mine albeit you have a ketch.

[CarlF]

I used four 125watt Solbian panels and they are all putting out the same watts as when they were installed on the bimini four years ago. I have heard some horror stories on other brands. Many seem to be made at the same large factory in China and different brand names applied. Of course, they are much less expensive than Solbian.

I mounted the panels on 8mm thick dual wall polycarbonate panels that are used for greenhouse windows. I got mine from Greenhouse Megastore. They have precut panels that were much cheaper to ship than the 4'x8' full sheets. Their cut panels were about an 1" smaller than the Solbian but it's done no damage to have the Solbian's hang over a little bit. There's been no noticeable chafe on the bimini.

These are extremely light (less than 1lb per solar panel) and last just about forever. They don't get noticeably warm, probably because of the air passages. They bend just enough to follow the curve of the bimini. I mount the panels with the long way fore and aft right over the bows. I attached the Solbian panels to the plastic it with 1" squares of 3M 4941 VHB tape every 12" or so. I covered the rough edges with a folded strip of white duct tape. None have let go even a little bit.

Another advantage of the plastic panel is that it is easy to remove the solar panel for storms or storage without them flexing too much in the process. I just just stack them on a berth.