Where to mount solar panels?

[Rhythmsmith]

I've been struggling with the issue of where to mount a good size solar panel on my Alberg 35 (sloop). I have a windvane installed so that eliminates mounting on the stern pulpit or adjacent area (due to windage that will affect the vane). Has anyone found a good solution that does not involve the stern rail, and doesn't get too shaded by the boom? If so, I'd like to know how they did it.
Thanks!

[Talbot]

Biggest problem with solar panels is that a shadow will decimate the output. Therefore if you cannot get a decent position for them such as the targa bar at the stern where shadows are less likely, you are better off mounting a number of smaller ones and thus increasing the chance that some of them are not in shadow.

[rebel heart]

A lot of people around here run stainless from the stern to the lifeline gate (a distance that is normally run by lifelines. From there you can mount them like "wings", with a bar on the outboard side that connects to the middle stainless bar, and some hinges or "hing like" options holding onto the top bar.

Not sure if that makes sense, but if you look around you'll see it. Shouldn't affect the vane on the back, and you can fold them flat when coming into a dock.

[Jentine]

You can find some mounting ideas here:

Boat Mounting Kits for Solar Panels

[Sailorguy]

Hello ...this is my first post to this forum. I chose to mount 3 - 75W panels over the bimini, with good results.

Steve

[Microship]

Having a variety of panels scattered about is almost essential unless you have room for a huge single array. The gotcha is partial shading, and paralleling them all doesn't work as the dark ones suck power from the bright ones. The trick we used on the Microship (photos below) is a custom peak power tracker that handles eight 60-watt "channels" independently, merging them together after power point optimization. That took a fair bit of custom electronics, though.

It would be worth asking MPPT vendors if they can support multiple instances of their product talking to the same battery bank. I haven't kept up with what's available lately, but it is worthwhile to do this (as opposed to the old Schottky diode approach that just wastes power all the time).

More simply, but human-error prone, is deploying the panels as needed and at the same time enabling them into a single max power point tracker (I'll be doing that on the new boat, though with proximity sensors on the folding modules taking care of the switching... it's a geek thing). The system mentioned by Rebel Heart lends itself well to this, and the wiring can be as simple as a toggle switch below for each panel that is folded out and in use.

One other tip, learned very expensively: let them breathe. We did a 480-watt array on foam-cored panels, and while they were structurally wonderful, they got HOT. I mean really hot. And that de-rates the output, stresses adhesives, shortens module life, and is unpleasant to be around. Anodized aluminum substrate with stringers and good airflow will translate into more power.

Cheers,
Steve

[Rhythmsmith]

Thanks Rebel Heart, that's what I'm gonna do. Run stainless tube and mount the panels like "wings". Seems like the best compromise all around.

[mcsromeo]

What is used as a clamp to attach the panels to the Stainless tube that runs from stanchion to stanchion. I've seen companies sell this conversion, but these parts have to be available commercially. Anyone out there know?

Thanks,

[CSY Man]

Hello ...this is my first post to this forum. I chose to mount 3 - 75W panels over the bimini, with good results.

Ditto, I mounted 2 X 75W back there with one more to be hinged at the aft for shading of cockpit and better "angle" for the late rays..

[Kanani]

Originally Posted by rebel heart

A lot of people around here run stainless from the stern to the lifeline gate (a distance that is normally run by lifelines. From there you can mount them like "wings", with a bar on the outboard side that connects to the middle stainless bar, and some hinges or "hing like" options holding onto the top bar.

Not sure if that makes sense, but if you look around you'll see it. Shouldn't affect the vane on the back, and you can fold them flat when coming into a dock.

I mounted mine that way too (for 10 years). It didn't effect the windvane at all. It was nice to be able to change the angle (for optimum absorbtion) out at sea too. When the weather packed up, I just folded them down and secured them.

[rebel heart]

I've also seen people run pvc over the lifelines for the same effect; cheaper than dropping a few grand for more stainless. My guess is that it works best for smaller panels, where there's much less weight.

[Kanani]

Originally Posted by rebel heart

I've also seen people run pvc over the lifelines for the same effect; cheaper than dropping a few grand for more stainless. My guess is that it works best for smaller panels, where there's much less weight.

I had 60w panels, 2 on each side (about 6' long altogether) but I had a 45', center cockpit boat too. Each boat is going to vary where they would best be mounted.

[rebel heart]

Originally Posted by Kanani

I had 60w panels, 2 on each side (about 6' long altogether) but I had a 45', center cockpit boat too. Each boat is going to vary where they would best be mounted.

Did you do the pvc way or stainless? I got quoted $2K to run that much stainless, and have been debating doing it.

[CSY Man]

Did you do the pvc way or stainless? I got quoted $2K to run that much stainless, and have been debating doing it.

I only spent a few hundred $ on all that stainless steel for my bimini mounting. (1" SS tube)
Easy to find used stuff, I used an old Bimini top frame for a 21' power boat as the "base", then added stuff around it..Check pics and if any questions, I'd be happy to add details.

[Kanani]

Originally Posted by rebel heart

Did you do the pvc way or stainless? I got quoted $2K to run that much stainless, and have been debating doing it.

I think I may have spent $20 on S/S tubing. I pop-riveted the panels to the tubing and (belive it or not) used heavy plastic wire ties (about 6 on each side) to secure to my pushpit and life lines. I didn't run the life-lines through the tubing. On the outside of the panels, I fastened 3/16" nylon braid to the pannel and ran the line down to an adjustment on my mizzen chainplates. The upper/outer lines went up to the mizzen rigging. Sounds rather crude but it looked nice and worked well.

I have had them battered by seas and strong winds. Never had a problem.

I have no still pics (all got wet). I have lots of video but don't know how to post it.