1st idea for solar panel mount

[Island Cessna]

I installed one 200w panel on our W36S late in the season last year. Due to the timing I don’t have much of a feel for overall performance, but it did work pretty close to Victron’s prediction for our location.

Our boat lost its mast a long time ago, replaced by a dinghy crane and a double 1 1/4” tube arch, so I was able to add the panel above the false stack behind the arch. I wanted to get it high enough that the shade from the radar antenna was minimized. I was more worried about aesthetics than performance, Bill Garden’s artistic talent is sacred to me, and I did not want to mess it up with the panel. It slopes aft parallel to the grey accent stripe on bottom edge of flybridge cowl. While it does not add to the artistic impression score I think the technical merit is adequate to offset any artistic deduction.

Based on the experience so far I have purchased a second identical 200w panel, and am in the process of making some aluminum angle supports to allow me to turn two panels 90° to lay side by side transversely on the same 7/8” tubing support frame.

I thought about articulating or adjustable angles but decided against the complexity. The main purpose of the panels is to extend the battery life while anchored, and as the boat swings randomly at anchor in nice weather (we prefer nice weather!), and the goal of being on the boat is relaxation, not chasing sun angles. I decided flat would probably be as good as I could achieve.

One thing I found with my late season 49° N latitude install was that on a cloudy day the 12 volt panel did not start up until the sun had been up for some time. The Victron controller needs a panel voltage a couple of volts above the battery voltage in order to start. I will wire the second panel in series to try to improve the length of daily run.

When we resume boating in the spring I should have the second panel installed, and will have some valid performance impressions to share.

Lostsailor, I too have a set of Bimini hoops that came with the boat, and some old photos with the Bimini. Ugly! I have a tonneau cover to keep the rain out, and if the weather is not good enough to be behind the flybridge venturi in the sunshine, we stay inside within arms reach of the coffee pot, and the furnace thermostat.

Bill

 

[AusCan]

My panels would rarely get adjusted, but others may be different. At anchor with the sun, wind, and current constantly changing I'd be chasing my tail trying to aim the panels the best direction. We are on about 35 degrees lattitude; At considerably higher latitudes it may be worth considering some sort of angle adjustment.

A single flat unshaded 250 watt panel on my hard bimini keeps the batteries topped up for an unlimited period with both a fridge and freezer running, so I don't have to worry about getting absolute maximum efficiency. Even at the dock, I rarely switch on the AC chargers. It's been running on solar alone for the past couple months, and the beer in the fridge is still cold.

 

[psneeld]

You don't have to adjust it/them.


You can leave them flat or any angle....do what your habits allow....doesn't have to be all the time or even every day...but having adjustable or portable solar panels gives options like Flywright also pointed out. And again...excess power allows for single angle mounting.


But just changing the angle once a day can result in many more amp hours a day.


Just seeing 10 amps out of 200W worth of panels minutes after sunup or minutes before sundown makes one a believer.

 

[Bud]

You don't have to adjust it/them.


You can leave them flat or any angle....do what your habits allow....doesn't have to be all the time or even every day...but having adjustable or portable solar panels gives options like Flywright also pointed out. And again...excess power allows for single angle mounting.


But just changing the angle once a day can result in many more amp hours a day.


Just seeing 10 amps out of 200W worth of panels minutes after sunup or minutes before sundown makes one a believer.

Lets say your on the hook or a mooring, which is where I use and need the solar power, and you adjust the panels at an angle mounted on the side of the boat what happens when the bow is facing the sun or the stern is facing the sun or the other side of the boat is facing the sun? You would meed panels on every side of the boat. Then if the sun is on the stern quarter your back to the sun hitting the panel at an angle. Even if you adjusted them flat you have shadowing issues that you would not have on top of the bimini or hard top. To me mounting them flat and accepting the slight inneffeciency is better than having the boat covered with solar panels that have to be adjusted and secured if the wind kicks up.
The biggest obstruction to efficiency is shadowing it is the first thing they caution in the various installation manuels. On a vessel they say to mount them as high up as possible or as far away from the mast as possible. A small shadow can knock out a larger portion of the output because some circuits on the panel are in series.

 

[psneeld]

Lets say your on the hook or a mooring, which is where I use and need the solar power, and you adjust the panels at an angle mounted on the side of the boat what happens when the bow is facing the sun or the stern is facing the sun or the other side of the boat is facing the sun? You would meed panels on every side of the boat. Then if the sun is on the stern quarter your back to the sun hitting the panel at an angle. Even if you adjusted them flat you have shadowing issues that you would not have on top of the bimini or hard top. To me mounting them flat and accepting the slight inneffeciency is better than having the boat covered with solar panels that have to be adjusted and secured if the wind kicks up.
The biggest obstruction to efficiency is shadowing it is the first thing they caution in the various installation manuels. On a vessel they say to mount them as high up as possible or as far away from the mast as possible. A small shadow can knock out a larger portion of the output because some circuits on the panel are in series.

Having portable/adjustable panels are just that...put them on an unused deck or bimini is a possibility. I also pointed out every boat is different and therefore shading might or might NOT be more significant for a little time opposed to when flat panels are producing near nothing and the portable/adjustable panels are producing over 50% for hours.


Just letting people know something they might consider.