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Old 04-02-2015, 10:20   #1
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Angle of solar panels

Hi, i'm planning out to mount solar panels on the davits. question is: should they be angled or just kept flat. i'm in sunny florida but was just wondering what the best choice is.'
thanks
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Old 04-02-2015, 10:27   #2
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re: Angle of solar panels

Angled to be normal to the sun is better by quite a lot. However, it is as impractical by the same amount. This is the reason most either mount them on a horizontal surface fore and aft, or mount them on an arch/rail athwartship with some ability to manually tilt them.

If you can figure out a mounting system that will allow you to tilt the panels in any direction depending on which direction the boat is facing - and are willing to stay with the panels all day, moving them as required - then you will get more efficiency out of them.

Mark
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Old 05-02-2015, 12:43   #3
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re: Angle of solar panels

i'll mount them flat, boat moves every hour due to wind and current. it's not a dock boat. thank you.
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Old 05-02-2015, 12:52   #4
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re: Angle of solar panels

I mount them with a little angle so that rain water drains off.
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Old 05-02-2015, 12:59   #5
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re: Angle of solar panels

good tip, thanks!!!!!!
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Old 05-02-2015, 21:29   #6
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re: Angle of solar panels

they should make ball solar panels
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Old 06-02-2015, 05:20   #7
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re: Angle of solar panels

Quote:
Originally Posted by colemj View Post
Angled to be normal to the sun is better by quite a lot. However, it is as impractical by the same amount. This is the reason most either mount them on a horizontal surface fore and aft, or mount them on an arch/rail athwartship with some ability to manually tilt them.

If you can figure out a mounting system that will allow you to tilt the panels in any direction depending on which direction the boat is facing - and are willing to stay with the panels all day, moving them as required - then you will get more efficiency out of them.

Mark
Indeed.
The ideal Solar Panel tilt is about equal to your latitude, plus 15 degrees in winter, or minus 15 degrees in summer.
Unfortunately, boats move.
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Old 06-02-2015, 06:43   #8
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Re: Angle of solar panels

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Originally Posted by GordMay View Post
Indeed.
The ideal Solar Panel tilt is about equal to your latitude, plus 15 degrees in winter, or minus 15 degrees in summer.
Unfortunately, boats move.
Actually, I was considering the benefit of following the sun angle throughout the day, not the latitude tilt.

Mark
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Old 06-02-2015, 06:52   #9
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Re: Angle of solar panels

good formula, Gordy. sound engineering!
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Old 06-02-2015, 07:33   #10
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Re: Angle of solar panels

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Actually, I was considering the benefit of following the sun angle throughout the day, not the latitude tilt.
Mark
Google <solar azimuth angle>.
Youíll find that minor variations off south produce very minor decreases in production.
For instance: an array with a 20 degree azimuth, the production is only 0.6% less than if the array pointed directly south.
For an array with a 70 degree azimuth, the production is 7.7% less than if it pointed south.
The azimuth angle specifies how many degrees the surface of the module or collector diverges from the exact south-facing direction.
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Old 06-02-2015, 08:13   #11
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Re: Angle of solar panels

Something isn't making sense to me here. In the morning when facing North, the sun here comes up on the East side of the boat, moves almost directly overhead, then proceeds to set in the West side of the boat.

If I could tilt my panels so that they were normal to the incident of radiation throughout the day, then I am pretty sure I would produce more than 0.6% extra power.

Same, but opposite directions if we are facing South all day.

Now, if we are facing East or West, the difference is much less.

BTW, I do understand azimuth - but that really isn't relevant on a boat.

Mark
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Old 06-02-2015, 08:19   #12
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Re: Angle of solar panels

Two of my four pivot so I can angle them to the afternoon sun... Remember the wind is always from the east in the tropics.

If you can make your pivot effectly you will get great extra electricity when you need it most - cooling the beer for sundowners!!
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Old 06-02-2015, 08:22   #13
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Re: Angle of solar panels

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Remember the wind is always from the east in the tropics.
Not always in our tropics. In fact, it is rarely from the East in the summer here, and typically N-NE in the winter.

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Old 06-02-2015, 08:47   #14
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Re: Angle of solar panels

I think the only time being able to angle your solar panels would be worth it is if you're in a place where your boat doesn't swing much. in a place like where Mark J is or on a river or of course at a dock that doesn't have electricity. The other thing to consider is how much do these brackets cost. I bought two stainless steel tubes and a couple of fittings to mount my panels flat on my bimini and it cost almost as much as the panels
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Old 06-02-2015, 09:00   #15
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Re: Angle of solar panels

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Not always in our tropics. In fact, it is rarely from the East in the summer here, and typically N-NE in the winter.

Mark
Its sue as hell not from the west!
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