Semi-flex Solar Panels on a Bimini

[ausnp84]

Hey guys,

I’ve got miles of fabric real eatate above my cockpit and would like to fit 4 x 140W semi-flex panels to it. Any thoughts on best way to do this? Glue, maybe stitch the edge of the panels through the fabric...?

N

[jibstay]

https://www.sailrite.com/How-to-Inst...ls-on-a-Bimini

[Mirage35]

I’ve been asking the same question and found loads of information: use the Google search link in the menu and try “solar Bimini” or something like that. (I tried to post a link to my search results but got a mess.)

To summarize, there are two schools of thought ...

[ausnp84]

Nice work guys! Thanks🙂

Nathan

[wcapman]

I followed the Sailrite installation guide for two 100w panels. They both failed after just a few months of use. Where the panels went over a bent (cross support) it put too much bend in the panel and caused an internal failure. I had even put some extra padding under the panel in that area to lessen the bend. I think the problem was the panels were installed in cooler weather and when the sun heated them up the bend angle increased to the breaking point internals of the panel, which to be honest wasn't all that much. Another issue I ran into was shading. My radar dome would cast shadows on a panel and reduce its power considerably. Between the radar and the boom I seldom got more than half of the rated power except under perfect conditions.


To solve this issue I plan to go back with 4 smaller panels of the same total wattage. These will be mounted so they do not span over a bent. They will be on fabric only between rigid braces. Another advantage of having smaller panels in parallel is if one panel becomes shaded the array will only lose about 15% of the output instead of 40% or more. Shaded panels still produce, but at a greatly reduced rate.

[julienb]

We've had great luck with having the flexible panels zippered onto flaps sewn into the bimini. Clearly required a professional sewing machine to sew the zipper through the plastic of the panels. There's also a stiffener between the panels and bimini.

[toddster8]

I like the idea of arranging them so that the whole thing could be folded and stored under a bunk or something when not needed. I.e. when in bay-sailing mode.

[Mahayana]

We added four 100W semifelx panels from GoPower by velcroing them to the Bimini. Adhesive hook side was attached to the back side of the panels. Loop side was stitched to the Bimini. We did not cross any Bimini bars. Each side has a separate Victron mppt controller. Works great!

[Wild Cherry]

When faced with adding an additional 60 or 80amp charger to my existing 40 amp charger (I have a generator), or fitting solar panels, it was a no brainer to go the silent route of solar panels. However I have never liked the look of the stainless gantry construct on the stern so flexible panels on the bimini it is. I am about to ship the panels to my yacht in Preveza but am battling to find someone in the Lefkas area who can can do the canvass work i.e. velcro, zippers, flaps etc. Can anyone please recommend someone in the area who can do this work. Much appreciated. (5 X 120watt panels and a 100/50 MPPT charge controller is what I have in mind).

[ausnp84]

Originally Posted by Mahayana

We added four 100W semifelx panels from GoPower by velcroing them to the Bimini. Adhesive hook side was attached to the back side of the panels. Loop side was stitched to the Bimini. We did not cross any Bimini bars. Each side has a separate Victron mppt controller. Works great!

That’s perfect! Thanks for the info. I’m thinking the s-same - I can get the four panels situated between bimini bars and velcroed in is a great idea. The velcro I can fit myself as well.

This is exactly why I love this forum! Thanks all.

Nathan

[Steve Perkins]

Originally Posted by ausnp84

That’s perfect! Thanks for the info. I’m thinking the s-same - I can get the four panels situated between bimini bars and velcroed in is a great idea. The velcro I can fit myself as well.

This is exactly why I love this forum! Thanks all.

Nathan

Hi Nathan

We are currently installing Solbian flexible panels on our Bimini to augment our existing rigid structures on the stern. We have Velcro to fix sewn on the edges of the panel as described above. I needed to reduce our desired panel size after taking advice from Philip at Solar 4 RVs in Melbourne Australia. It was clear if we used all our area there would be a curved radius in multiple directions. The panels can curve gently up to about 10 degrees but only ever bending in one plane. The advice was never to cross any hard structures, ensure the entire panel is supported eg don’t suspend over free space, and use a bit of cardboard to test the bend radius first. On the last point I was surprised to find complex curves on our boat that the cursory initially glance hadn’t picked up (necessitating smaller panels).

Solar4RVs will happily email a comprehensive guide to install with many pictures of both good and bad panel installation if you click the contact link on their site. Btw, I am in no way affiliated with them, just a happy customer with one transaction done.

All the best of luck for your install!

Steve

[Gintonix]

Regarding the question about canvas work in Preveza:

Waypoint are highly regarded sailmakers, I had good serice from them, although I doubt they will take on a small job like this. Worth a try.


We used Takis Paspalidis of Yacht Shelter to make us a boat cover. Good work and service, done on schedule. More likely to take on a solar fitting to your bimini.


Both are able to get access to Cleopatra if that is where you are wintered.


Cheers

[Cpt Pat]

Caution: flexible panels really should be called "bendable" panels, or "camberable" panels. They have a limited flex-life before fatigue causes breaks in the bonding wires, or substrate delamination caused by flexing stresses between substrate layers leads to water intrusion (seawater rapidly dissolves aluminum bonding wires).

They can be mounted on a cambered surface, but if that surface isn't rigid, or in the worst case the panels are self-supporting while flapping in the wind, the continual flexing will cause them to fail. The Bimini frame needs to be carefully stiffened to prevent panel flexing.

[css145hs]

Originally Posted by Cpt Pat

Caution: flexible panels really should be called "bendable" panels, or "camberable" panels. They have a limited flex-life before fatigue causes breaks in the bonding wires, or substrate delamination caused by flexing stresses between substrate layers leads to water intrusion (seawater rapidly dissolves aluminum bonding wires).

They can be mounted on a cambered surface, but if that surface isn't rigid, or in the worst case the panels are self-supporting while flapping in the wind, the continual flexing will cause them to fail. The Bimini frame needs to be carefully stiffened to prevent panel flexing.

+1 It's the cycling that kills them, and wind is the concern on fabrics, so keep it taught/stiff. Also if mounted on a hard surface, they can also perform very poorly in tropics heat (50% worse), as they don't have airflow beneath them like normal panels would. Their ultimate service life, even if things go well, is also less, so cost over a longer span of 10-20 years can be worse depending on the specifics of an install... and their efficiency at off-angles is also often worse so total daily production is less... all things to consider. They are damn convenient though!

[kas_1611]

I tie my 100w semi flex panel on top of my bimini so I can remove it at the end of the trip and pack away my bimini completely. Not had a problem with the panel in winds over 40kts.

I also have 2x 35w fully flex panels that I also tie onto the top of the bimini for added wattage.

Admittedly the top of the bimini does look a little like a cats cradle but no one ever looks up there so who cares.