Am I putting too much solar on my arch?

[nuru05]

So we recently bought a Moody 425 and are going to move aboard in a couple of weeks. I'm trying to figure out how much solar I can cram onto it and just want to make sure that I'm not overdoing it. As you can see from the walkthrough I've linked I have a modest arch over the stern, my plan was to have a welder use some 2"x2"x1/4" aluminum angle to make a box that will be 88" (the width of the arch now) x about 120". This would enable me to mount 6 of these 200w panels. I'm not too worried about weight (the entire thing with the panels and frame should only weigh about 250#) but I'm wondering if that's just too much for wind to catch or some other issue I'm not considering.

https://kuula.co/share/NGNJ5/collect...oad=0&thumbs=1

https://richsolar.com/collections/ri...lt-solar-panel

[Orion Jim]

Have you considered sliding extensions? Minimize the windage when sailing and maximize the solar exposure when in calm conditions or an anchorage/slip.

https://www.youtube.com/watch?v=F27yfLGhazE

[Rumrace]

I have 4 100 watt suspended above our Bimini and 6 100amp batteries. We’ve two fridges two plotters 3 2 speed winches and never run out of juice. I haven’t a clue if it’s perfect but touch faux wood everything works. There are a few experts here on the topic who seem to confirm my system is adequate.
Love the Moody hope you make great memories on her. Congratulations. Hoot Hoot.

[wingssail]

Originally Posted by nuru05

So we recently bought a Moody 425 and are going to move aboard in a couple of weeks. I'm trying to figure out how much solar I can cram onto it and just want to make sure that I'm not overdoing it. As you can see from the walkthrough I've linked I have a modest arch over the stern, my plan was to have a welder use some 2"x2"x1/4" aluminum angle to make a box that will be 88" (the width of the arch now) x about 120". This would enable me to mount 6 of these 200w panels. I'm not too worried about weight (the entire thing with the panels and frame should only weigh about 250#) but I'm wondering if that's just too much for wind to catch or some other issue I'm not considering.

https://kuula.co/share/NGNJ5/collect...oad=0&thumbs=1

https://richsolar.com/collections/ri...lt-solar-panel

If I understand this correctly you will have a box which is 7' wide and 10' long, made out of aluminum angle stock, on which you will mount something over 70sq ft of solar panels which will weigh, including the framework, about 200 lbs and will be suspended something like 5' in the air extending out over the stern.

A lot of people these days are doing similar things however having that weight and windage up there in the air always does bad things for the boat; it's windage being one, and moment of inertia being another. This affects the sailing ability, the roll stability and increases the propensity for hobby horsing. The Moody is a wonderful sailing boat and in my opinion it is a shame to do so much to detract from that.

My guess is that you will probably go ahead with this because you want all that power so you can make you boat more house like and sailing isn't that important to you (or you wouldn't propose this in the first place).

But if you do, I suggest that you make that frame very strong and massively anchored into the hull, because in a seaway that is a lot of weight to toss around up there. For sure you should not use the existing stern railing as part of the structure.

Finally, consider looks, it's going to be huge and aluminum angle will look home made. If you can't make it smaller, at least make it nice with welded stainless steel tubes.

Oh, and what about the wind vane?

[anotherT34C]

Inspired by Mads (above video) I’m going to mount two more panels on my hard bimini, but unlike Mads I’m going to have then swing out rather than slide out. Simpler, and gives me the option to adjust their orientation to the wind.

[svtickles]

Originally Posted by anotherT34C

Inspired by Mads (above video) I’m going to mount two more panels on my hard bimini, but unlike Mads I’m going to have then swing out rather than slide out. Simpler, and gives me the option to adjust their orientation to the wind.

Would love to see the finished product!

[RaymondR]

"Finally, consider looks, it's going to be huge and aluminum angle will look home made. If you can't make it smaller, at least make it nice with welded stainless steel tubes."

I used aluminium angles to build the frames for my panels and got around the "ugly" problem and stiffened the frame by splitting tube and tacking it around the outside of the frame.

[wingssail]

Originally Posted by anotherT34C

Inspired by Mads (above video) I’m going to mount two more panels on my hard bimini, but unlike Mads I’m going to have then swing out rather than slide out. Simpler, and gives me the option to adjust their orientation to the wind.

Be very careful about the engineering of this. To swing out you will need a pivot onto which the entire weight of the panel will be suspended. The leverage of the weight will be great, as will the leverage of the wind. And to adjust the orientation I presume your will want to rotate the panels as well as swing them. A 2-axis pivot will need special attention and the panels themselves will need stronger frames than the aluminum ones that they come with.

[Pete7]

Sorry, but I don't think that arch will support 162lbs of solar panels in a gale. I think you could use it and add another matching frame several feet forward and joined together to mount the panels.

You probably want to consider moving the radar and loosing the windmill because both will give shadows affecting the solar output.

Pete

[SailFastTri]

Originally Posted by nuru05

So we recently bought a Moody 425 and are going to move aboard in a couple of weeks. I'm trying to figure out how much solar I can cram onto it and just want to make sure that I'm not overdoing it. As you can see from the walkthrough I've linked I have a modest arch over the stern, my plan was to have a welder use some 2"x2"x1/4" aluminum angle to make a box that will be 88" (the width of the arch now) x about 120". This would enable me to mount 6 of these 200w panels. I'm not too worried about weight (the entire thing with the panels and frame should only weigh about 250#) but I'm wondering if that's just too much for wind to catch or some other issue I'm not considering.

https://kuula.co/share/NGNJ5/collect...oad=0&thumbs=1

https://richsolar.com/collections/ri...lt-solar-panel

2"x2"x1/4" aluminum angle won’t be strong enough. It’ll sag and self destruct. I saw someone else who took a similar approach and he had to start over with a different design. It was sad because it cost him a lot of time, effort and expense.

[Pete7]

This is 600w and its not as rigid as I had hoped. Fine with 300w, might need more support for the current 600w.

Second photo is were you don't want to go

Edit, I have just seen the date of the original post.

[argosail]

Originally Posted by Rumrace

I have 4 100 watt suspended above our Bimini and 6 100amp batteries. We’ve two fridges two plotters 3 2 speed winches and never run out of juice. I haven’t a clue if it’s perfect but touch faux wood everything works. There are a few experts here on the topic who seem to confirm my system is adequate.
Love the Moody hope you make great memories on her. Congratulations. Hoot Hoot.

Where do you sail? In the tropics seems fine but further north :/