Solar Panels - Bimini or Davits - Pros and Cons of Both

[rover88]

Davits!!

I have been studying the same issue for months and decided that the Kyocera 135 panel would get a thin bit of shade from my back-stay and wind gen if I went the bimini route. I understand that the slightest bit of shading will diminish the output.

Have also considered installing adjustable hatch mounts so that the panel can be angled to get the optimum sun.

[ReMetau]

We have a Solar Stik with a Kiss mounted on top of that. We plan to mount another larger panel on our davits that can tilt forward and aft. We found out that someone is making a panel that can also collect solar from the back of it via reflection from the water.

[S/V Alchemy]

Originally Posted by JDGreenlee

Those with solar panels on their bimini, did you reinforce your existing bimini and how (starboard panel mounts and/or rails to the stern pulpit), or did you opt for a different beefier bimini, and by beefier do you mean wall thickness or stance or both? Has anyone simply extended their bimini horizontally to accomodate additional solar panels?

My experience may be informative. The panels ARE the bimini:

The World Encompassed: Fiat lux, baby

Further tweaks and positionings will be required, but I don't like davits in the ocean and where I have mounts for davits are slated to hold a deck crane and a wind generator pole. So this was it.

The other option are rail-mounted panels that are lashed flat underway and held up with a strut at anchor. I've seen this and it works, but obviously you don't use the sunshine on passage.

[Bash]

Originally Posted by rover88

I understand that the slightest bit of shading will diminish the output.

You understand correctly. And the loss is disproportionate to the shade. A shadow that only covers 10% of the panel can cut its output by half. Even a bit of bird guano can cost you a couple of amps.

[endeavor]

Another plus for installing the panels on the davits for me anyhow is the extra weight aft. I plan on getting a 200' of chain that is going to end up in the bow so that weight should even things out.

[S/V Alchemy]

That's not entirely true. Putting weight at either end is just like putting fatter kids on a see-saw: the tendency to pitch, and to pitch faster, increases. Depending on your boat it might not be an issue, but I would hesitate to recommend bolting panels two feet off the stern to solve a "weight in the bow" problem.

[zeehag]

just bought my 50 dollar bimini-- i will look at it in am to see how to installit--then the panels willgo there--- and it is going to also be , ultimately, boom gallows formy mizzen... the frame fits perfect--i havent checked hight yet....
as for weight in bow and stern, need to make sure there is weight in midships moreso than bow and stwern-- bow and stern will make y0ur boat hobbyhorse..not a good sea motion.

[Pelagic]

Originally Posted by Southern Star

Mine are installed above my davits and if you are able to do the same, IMO it is the best option:

1. you will definitely get less shading - especially with the mainsail up, but also under anchor.
2. it tends to be a sturdier mounting location than a soft bimini.
3. it does not interfere with the function of the bimini, or the ability to take it down in storm conditions.
4. it permits easier adjustment, at least for and aft.
5. the solar panels also provide something of a 'roof' for the inflatable, reducing the amount of rain water that can get into the inflatable and also the exposure of the fabric to UV rays.

Brad

Would love to see a photo of what you did.

My reasoning is the same as yours and because I am a schooner rig with a lot of aft stays, the above davit solution seems the best as I show conceptually in yellow at existing awning height to make working the tender on the davits easy.

Any comments or concerns appreciated.

[ozskipper]

Davits are a permantant fixture, where as a bimini is designed to be folded out of the way and even removed in severe weather. If you fix to the bimini you may remove the flexibility of its design.

Where as the Davits, being a permanent structure shouldnt pose a future issue. A lesser benifit is that being on davits they are just that little further aft of any shadows the mainsail may create.

Cheers
Oz

[Cotemar]

Tilting Solar Panel on Davits
http://www.cruisersforum.com/forums/...tml#post491749

[NDH]

Originally Posted by Cotemar

Tilting Solar Panel on Davits
http://www.cruisersforum.com/forums/...tml#post491749

That is a really nice job, I was going down the route of installing on the bimini, I might have a rethink now

[Strygaldwir]

We have been caught in two named storms (securly tied up at a marina). Three times we have taken the bimini down. I was very glad I had the option. A number of boats received significant damage to canvas, biminis and enclosures, during both storms. I suppose if you could remove the canvas/Sunbrella or had a solid top, a lot fewer issues in that regard. But, it should be a consideration.

Our panels are mounted accross our davits. I selected this location due to the ease of installation, ready access, length of the wires from the panels to controller and not being shaded from boom and sails.

Ease of installation - I didn't know whether the panels were going to provide a resonable amount of power, so I wanted a straight forward installation, that minimized cost. They are a great option for power, so permanate installation was in order.

Ready access - I wanted to be able to fix any issues that arose on the panels, so I wanted to be able to get to them without much ado. Well no issues with the panels, but I do rinse them off when they get dusty or dirty. Very easy.

Wire length - Major consideration! The wire needs to be as short as possible. I imagine I save 10 feet or more by mounting them closer to the controller and batteries. Since this is doubled, I save significantly on the necessary rating of wiring.

Shading - Shade on the panels can result in significant lose of power from the panels. It is a whole lot more challenging to deal with when the panels are directly below the beam. pushing them out and away helps. Ideally, I think they should be mounted on the same level as the beam, but that well be done when I construct new enclosure.

[endeavor]

I have been on many deliveries one across to Spain from Bermuda and several to BVI's. We have always rolled back and lashed the bimini as a precaution. I like having that option available. I've heard it mentioned several times that one drawback to having the panels on the davits is that during large following seas they get ripped off the davits. I wonder how often that could actually happen. I would think that it would have to be a very large storm at just the right following conditions. As a matter of fact I personally don't know anyone who has had them ripped off from the davits but I have known many people who's bimini's have been damaged by a sudden squall. By the way I am not a circumnavigator.

[Mark Johnson]

We have been through over a dozen hurricanes, with one, (IVAN), on the border between a 3 and 4, (150 MPH gusts), with a 14' surge! My panels have survived them all, with no damage.
The aft hinged panel has VERY thin kevlar hold down lines, that I rig up in these storms, and the panel's frame is INSIDE a really beefy aluminum frame. The SS rack has gusset bars in two directions, and is light but STRONG!

Be sure not to put a wind gen where it will shade the aft panel, or you defeat the purpose, and deck mounted panels need to have ventillation underneith to keep them cool, as well as "NO LINE SNAGGING" corners, like shown... M

[zeehag]

i have no davits on my boat. had too much fun snapping them off the boat we cruised last year .... however, the bimini we used on same boat was a solar panel bimini that didnt come down/remove. and even in severe storms wasnt a problem. mine will be as a boom gallows for mizzen boom by the time i am done with it..