Mounting panels on davits or bimini

[flightlead404]

I'm working on my solar design and considering mounting locations.

Boat is a Hunter 38, so I have the traveller arch to deal with.

I'm trying to decide if I should mount panels on the bimini or over the davits.

On the davits I would have more room, can solidly mount the panels, don't have the traveler arch to deal with, and would have no shading from the boom which would of course always be shading panels on the bimini. Depending on sun direction the davit location would still ofc suffer from shading from mast, and sails if underway, but minimal or even nothing if near noon or sun behind us.

My only concern with the davits is putting the weight so far back and adding windage. I'm considering 4x180W NEwPowa panels. They are 58.4x26.6 so I would arrange them into 117"x53" and total weight of the panels and weigh slightly over 25lbs each.

Would this area and weight be a problem?

[rslifkin]

What about 2 on the bimini (either one on each side, or both across the bimini as far aft as possible to minimize shading) and then the other 2 on the davits? Looking at the Hunter 38 in the slip next to mine (and picturing davits added to it), that seems like it might strike the best balance of added bulk / windage, not putting weight too far aft, and minimizing shading. Panels on the bimini are a lower windage penalty, I think.

[George_SD]

Davits is a better location and potentially offers stronger connection to the boat. I would just suggest to look at the mounts for the davits and see if they may need to be reinforced. My concern would be that they are not mounted vertically, but are typically installed at an angle, which creates significant leverage on the mounts depending on how much weight is added to the top. Adding tubing to the boat or installing bigger backing place may be the way to address this.

The other question is - are you cruising in places with really strong winds?

[flightlead404]

Originally Posted by George_SD

Davits is a better location and potentially offers stronger connection to the boat. I would just suggest to look at the mounts for the davits and see if they may need to be reinforced. My concern would be that they are not mounted vertically, but are typically installed at an angle, which creates significant leverage on the mounts depending on how much weight is added to the top. Adding tubing to the boat or installing bigger backing place may be the way to address this.

The other question is - are you cruising in places with really strong winds?

SE US, possibly bahamas.

Davits are not straight up and down, but are angled. They attach to the traveler arch as well, which is darn stout.

I weight 200lbs and can do chin ups on the davits no problem, dingy weighs around 100ish and I don't put it on the davits with the OB on it or anything other than oars and its bridle attached.

On this boat I don't think I can really put in any vertical supports, there are stern lockers on the transom step which would be a problem. But, I could add some additional trianglulation.

[flightlead404]

Originally Posted by rslifkin

What about 2 on the bimini (either one on each side, or both across the bimini as far aft as possible to minimize shading) and then the other 2 on the davits? Looking at the Hunter 38 in the slip next to mine (and picturing davits added to it), that seems like it might strike the best balance of added bulk / windage, not putting weight too far aft, and minimizing shading. Panels on the bimini are a lower windage penalty, I think.

hmmm.....splitting them up isn't an approach I'd consider. Heading to the boat in a few hours, I'll take a look and see what's possible.

I have a love/hate relationship with that traveler arch. Mostly hate I think.

[hlev00]

Here is a write-up my setup. Consider how much shade you will get from your radar. If it is mast mounted, obviously you won't have any problem. My old Questus mount was quite high up but mounted to the port side split backstay. While this did result in some shading it was mitigated by splitting the four panels into two to starboard and two to port with separate controllers. Splitting also gives me redundancy and protection for shade caused by the mast as we drift back and forth on anchor or a mooring.

https://juno423.blogspot.com/2020/08...th-photos.html

If I wanted / had and arch with davits, I would have gone first to solid panels on the davits, then if I wanted more solar look at the bimini or dodger. The dodger has obvious issues with the boom but we do miss being able to have the bimini down during shoulder seasons in New England where some sun in the cockpit is welcome.

Harry

[Moontide]

That amount of weight shouldn't be a problem, especially if you are doing chinups on it. As far as windage, the panels are primarily horizontal so the loading is minimal. If they were vertical would be a different story.



You can always move the boom outboard if you decide to go on the bimimi. Common way to solve boom shading issue.



Doubt there is room, but mounting on the lifelines so they rotate to horizontal might be an alternative. Have to lower coming into a dock but once out on the water that's no issue.

[wholybee]

Originally Posted by Moontide

...
Doubt there is room, but mounting on the lifelines so they rotate to horizontal might be an alternative. Have to lower coming into a dock but once out on the water that's no issue.

This is my solution, and it works very well. Gets them out from under the boom, have some adjustability to angle towards the sun, and spread apart enough that if some get shade, the others will not. Sailing, even in rough seas with strong wind (to about 25-30 kts) is not a problem. Higher than that I fold them down and secure them.

I have a windvane, so no davits, and like to be able to take down my bimini, so that was my option. But even with panels on davits and a bimini, I would still have additional panels on the lifelines. It's just too coinvent of a place to not take advantage of it.

[jeff356]

Have a Hunter 356 with arch and davits also and planning on putting 2 larger panels on the arch and a smaller panel on the davits.

Tying into the arch just behind the traveler and going back to the end of the Bimini would give you the most bang for your buck, and as long as you brace it should have no problem with wind.

With our davits I remove the cross bar for slip space but if traveling I would mount a smaller panel across the brace as I got the double brace to better support a panel, and more amps just keeps the batteries happy and generator run time down...

Jeff

[singlespeed]

A lot is dependent on the weight of your dinghy (and motor, if you hoist them both and travel that way). Not only does the davit mount location of the solar panels provide additional protection from clumsy guests who like to set things in convenient locations and dropped tools, it also helps prevent rain accumulation in your raised dinghy.

[j.g.evans]

Without a picture of your set up I can only offer general suggestions. I had a Hunter 40 with a custom made arch. I mounted 4 panels high as a continuation of the bimini with a small canvas panel. This worked great for sun and rain protection. The arch was high and I would hoist the dinghy high for ocean passages. I hoisted it lower to see over it for the Inter Coastal. I made a crane to lift the outboard off the dinghy and place it on the stern rail.

[flightlead404]

As I'm in the early stages of trying to design a new bimini/cockpit enclosure and find someone near hilton head to build it for me, I'm just going to mount 2 of the highest wattage panels that will fit across the boat and put them on the davits with the plan to add 2 more elsewhere if necessary. I will add some more bracing if needed.